Mold flaw detection method and mold flaw detection apparatus

Abstract

This invention discloses a method and equipment for detecting mold etching. The detection method includes acquiring a global image of a turntable and the mold to be inspected on it, and establishing a turntable coordinate system; identifying the detection area of ​​the mold to be inspected through a controller, and dividing the detection area into an etching texture detection area, a surface defect detection area, and a cavity size and position detection area to determine the coordinate range of the points corresponding to each detection area; the controller generates a detection motion trajectory for each detection area based on the coordinate range of the points; the controller controls a rotary drive device to drive the turntable to rotate, positioning the mold to be inspected at the shape detection station, defect detection station, and dimensional tolerance detection station; in this way, the quality qualification judgment of all indicators of mold etching can be completed, and the trajectory matching of different detection items can be achieved, avoiding the detection blind spots caused by the disconnect between the trajectory and the detection requirements, so as to adapt to the detection of molds with complex cavities and multi-area etching, and ensure the comprehensiveness and accuracy of the detection.

Description

Technical Field

[0001] This invention relates to the field of mold etching inspection equipment, and in particular to a mold etching inspection method and mold etching inspection equipment. Background Technology

[0002] Currently, the industry relies on inspectors to visually inspect and use magnifying glasses to screen for surface defects in mold etching, and then use handheld roughness testers, 2D image analyzers, and coordinate measuring machines to check texture accuracy and dimensional tolerances. This approach has several drawbacks: First, it is extremely inefficient, requiring multiple inspections and repeated clamping of a single mold using multiple machines, which is unsuitable for the inspection needs of batch molds. Second, it suffers from poor accuracy and consistency, as manual visual inspection cannot identify micron-level scratches, pinholes, and groove depth deviations, and the inspection results are greatly affected by the inspector's experience and subjective state, making it impossible to guarantee batch consistency. Third, it carries a high risk of mold damage, as repeated manual handling and clamping of molds can easily scratch and bump the precision etched surface, causing mold scrap and significantly increasing production costs. Later, automated inspection equipment appeared on the market. However, texture accuracy inspection, surface defect inspection, and dimensional tolerance inspection need to be completed on three separate machines. The mold still needs to be clamped and positioned multiple times. The cumulative positioning error caused by multiple clamping seriously affects the inspection accuracy. Moreover, the process is scattered and the inspection process is long, making it impossible to achieve continuous inspection of all indicators. Furthermore, since each inspection item is carried out on different machines, the coordinate system and clamping datum are difficult to unify, resulting in a lack of correlation between morphological data and dimensional tolerance data, which is not conducive to evaluating the overall quality of mold etching. In addition, the current rotary automated inspection equipment lacks global calibration and trajectory pre-planning before inspection. The coordination between station flow and inspection action is poor, the inspection cycle is unstable, and consistency is difficult to guarantee during batch inspection. Furthermore, the inspection area division and inspection trajectory planning are disconnected, which easily leads to inspection blind spots and cannot be adapted to complex cavities.

[0003] Therefore, a new technical solution needs to be researched to address the above problems. Summary of the Invention

[0004] In view of this, the present invention addresses the deficiencies of the existing technology, and its main objective is to provide a mold etching detection method and a mold etching detection device. It collects detection data of corresponding dimensions through three detection stations and transmits them uniformly to the controller. Based on the same turntable coordinate system, it realizes the fusion management of multi-source detection data. In this way, it can complete the quality qualification judgment of all indicators of mold etching and realize trajectory matching of different detection items, avoiding detection blind spots caused by the disconnect between trajectory and detection requirements. It is suitable for the detection of molds with complex cavities and multi-area etching, ensuring the comprehensiveness and accuracy of the detection.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for detecting etching patterns on a mold, comprising an instrument for detecting etching patterns on a mold, the instrument including a machine base, a turntable mounted on the machine base, and a controller; and including the following steps: Step S1: Obtain a global image of the turntable and the mold to be inspected on it, and establish a turntable coordinate system to determine the coordinates of any position on the turntable in the turntable coordinate system; Step S2: The controller identifies the detection area of ​​the mold to be inspected and divides the detection area into an etching texture detection area, a surface defect detection area, and a cavity size and position detection area to determine the coordinate range of the points corresponding to each detection area; the controller generates a detection motion trajectory for each detection area based on the coordinate range of the points and stores the detection motion trajectory in association with the preset standard detection parameters; Step S3: The controller controls the rotary drive device to drive the turntable to rotate, so that the mold to be inspected is positioned at the morphology inspection station; the controller controls the morphology inspection device to scan the etching texture inspection area according to the inspection motion trajectory, so as to obtain the first inspection data and transmit it to the controller. The first inspection data includes the groove depth and texture spacing of the etching. Step S4: After step S3 is completed, the controller controls the rotary drive device to drive the turntable to rotate, so that the mold to be inspected is positioned at the defect inspection station; the controller controls the defect inspection device to collect images of the surface defect inspection area according to the inspection motion trajectory, so as to obtain the second inspection data and transmit it to the controller. The second inspection data includes the collection of surface scratches, pinholes, pits, and corrosion defects. Step S5: After step S4 is completed, the controller controls the rotary drive device to drive the turntable to rotate, so that the mold to be inspected is positioned at the dimensional tolerance inspection station; the controller controls the dimensional tolerance inspection device to scan the cavity dimension and position inspection area according to the inspection motion trajectory, so as to obtain the third inspection data and transmit it to the controller. The third inspection data includes the overall dimensions and dimensional tolerance data of the cavity.

[0006] A mold etching inspection device and its mold etching inspection method include a feeding station arranged along the circumference of a turntable, a morphology inspection station for inspecting the groove depth and texture spacing of the surface to be inspected in the mold etching process, a defect inspection station for inspecting scratches, pinholes, pitting, and corrosion on the mold etching surface, and a dimensional tolerance inspection station for inspecting the overall dimensions of the mold cavity. The machine base is equipped with a morphology inspection device, a defect inspection device, and a dimensional tolerance inspection device respectively at the morphology inspection station, the defect inspection station, and the dimensional tolerance inspection station. The inspection ends of the morphology inspection device, the defect inspection device, and the dimensional tolerance inspection device face the turntable. The rotation drive device, the morphology inspection device, the defect inspection device, and the dimensional tolerance inspection device are electrically connected to a controller.

[0007] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solution, it mainly collects detection data of corresponding dimensions through three detection stations and transmits them to the controller in a unified manner. Based on the same turntable coordinate system, it realizes the fusion management of multi-source detection data. In this way, the quality qualification judgment of all indicators of mold etching can be completed in a comprehensive manner. In particular, the turntable circular layout is adopted, and each station is evenly arranged along the circumference of the turntable. The overall structure of the equipment is compact and occupies a small area. Secondly, by acquiring global images of the turntable and the mold to be inspected, a unified turntable coordinate system is established to determine the coordinates of any point on the turntable. This provides a unique reference coordinate system for subsequent inspection area division, inspection trajectory generation, and multi-station continuous inspection, thereby solving the problems of inconsistent references and cumulative positioning errors caused by multiple clamping in multi-process inspection, ensuring the consistency of dimensional inspection data, and improving the stability of inspection accuracy. Next, the effective detection area of ​​the mold to be inspected is automatically identified and specifically divided into etching texture detection area, surface defect detection area, and cavity size and position detection area. The coordinate range of each area is locked, and a detection motion trajectory adapted to the corresponding detection requirements is generated based on the coordinate range. In this way, the trajectory matching of different detection items is achieved, avoiding detection blind spots caused by the disconnect between the trajectory and the detection requirements. This adapts to the detection of molds with complex cavities and multi-area etching, ensuring the comprehensiveness and accuracy of the detection. In addition, by adopting a rotary multi-station intermittent transfer scheme, the mold to be inspected can be sequentially transferred to the morphology inspection station, defect inspection station, and dimensional tolerance inspection station simply by rotating the rotary table after being clamped and positioned once. This completes the full inspection of texture accuracy, surface defects, and dimensional tolerances, eliminating the need for multiple disassembly and repositioning of the mold, simplifying the inspection process, and adapting to the inspection needs of industrial batch molds. At the same time, it avoids scratches and bumps on the etched surface caused by repeated manual handling and clamping, effectively reducing the risk of mold scrap and improving production yield. Furthermore, by associating and storing the detection motion trajectory with preset standard detection parameters, when batch-testing molds of the same specification, the pre-stored trajectory and standard parameters can be directly called, eliminating the need for repeated coordinate system calibration and trajectory planning. This shortens the preparation time for batch testing, eliminates batch differences caused by manual operation, and ensures the consistency and repeatability of the test results for the same batch of molds. The test data can be archived and stored synchronously, realizing traceable management of the entire mold testing process to meet the needs of online continuous testing on production lines.

[0008] To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0009] Figure 1 This is a perspective view of an embodiment of the present invention; Figure 2 This is a side view of an embodiment of the present invention; Figure 3 This is a structural diagram of the morphology detection device according to an embodiment of the present invention; Figure 4 This is a structural diagram of the clamping mechanism according to an embodiment of the present invention; Figure 5 This is a structural diagram of the clamping mechanism according to an embodiment of the present invention (clamping position adjustment); Figure 6 This is a control block diagram of an embodiment of the present invention.

[0010] Explanation of reference numerals in the attached diagram: 10. Machine base; 11. Rotary drive device; 12. Clamping mechanism; 13. Clamping position; 14. First clamping assembly; 15. Second clamping assembly; 141. Clamping drive component; 142. Clamping block; 20. Turntable; 30. Controller; 31. Data processing module; 40. Material loading station; 50. Shape inspection station; 51. Morphology detection device; 52. First support frame; 53. First lifting mechanism; 54. First detection head; 55. Movable board; 56. Vertical board; 57. Vertical drive device; 58. Horizontal drive device; 60. Defect inspection station; 70. Dimensional tolerance inspection station; 61. Defect detection device; 62. Second support frame; 63. Second lifting mechanism; 64. Second detection head; 71. Dimensional tolerance inspection device; 72. Third support frame; 73. Third lifting mechanism; 74. Third detection head. Detailed Implementation

[0011] Please refer to Figures 1 to 6 As shown, it illustrates the specific structure of an embodiment of the present invention.

[0012] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0013] A method for detecting etching patterns on a mold, comprising an instrument for detecting etching patterns on a mold, the instrument including a machine base 10, a turntable 20 mounted on the machine base 10, and a controller 30; and including the following steps: Step S1: Obtain a global image of the turntable 20 and the mold to be inspected on it, and establish a coordinate system for the turntable 20 to determine the coordinates of any point on the turntable 20 in the coordinate system of the turntable 20; The coordinate system of turntable 20 is established with the central axis of turntable 20 as the Z-axis, the upper surface of turntable 20 as the XY plane, and the 0° reference position of turntable 20 as the positive direction of the X-axis. The origin parameters of the coordinate system are fixed in controller 30. The pixel physical coordinate transformation calibration is performed by controller 30 controlling turntable 20 to transfer the calibration block to defect detection station 60. The second lifting mechanism can be controlled to drive the area array industrial camera to adjust to the calibration focal length position and capture a clear global image of the calibration block. The FPGA hardware image processing module of controller 30 extracts the pixel coordinates of the checkerboard corner points, combines the known actual physical size of the corner points, solves the pixel equivalent, and performs lens distortion correction to establish a transformation matrix between image pixel coordinates and global physical coordinates. Step S2: The controller 30 identifies the detection area of ​​the mold to be inspected and divides the detection area into an etching texture detection area, a surface defect detection area, and a cavity size and position detection area to determine the coordinate range of the points corresponding to each detection area; the controller 30 generates a detection motion trajectory for each detection area based on the coordinate range of the points and stores the detection motion trajectory in association with the preset standard detection parameters. Preferably, the standard testing parameters include at least the standard value and tolerance of the etching groove depth, the standard value and tolerance of the texture spacing, the defect acceptance standard, and the overall dimensional tolerance and geometric tolerance standard of the cavity. It should be noted that the standard testing parameters of each part can be set, coded and stored according to actual needs.

[0014] The coordinate systems of each detection device are controlled by the controller 30 to rotate the calibration block sequentially to the topography detection station 50, the defect detection station 60, and the dimensional tolerance detection station 70 via the turntable 20. The controller controls the three major detection devices to collect the reference feature data of the calibration block and extract the coordinate values ​​of the reference hole and standard step in the coordinate system of each detection device. The transformation matrix (translation, rotation, and scaling parameters) between the coordinate system of each detection device and the global coordinate system is solved by the least squares method and pre-stored in the controller 30 to complete the unification of the coordinate reference of the three major detection devices. Step S3: The controller 30 controls the rotary drive device 11 to drive the turntable 20 to rotate, positioning the mold to be inspected at the morphology inspection station 50; the controller 30 controls the morphology inspection device 51 to scan the etching texture inspection area according to the inspection motion trajectory, so as to obtain the first inspection data and transmit it to the controller 30. The first inspection data includes the groove depth and texture spacing of the etching. Preferably, the morphology inspection device 51 includes a first lifting mechanism 53 and a first inspection head 54 disposed on the first lifting mechanism 53. In step S3, the controller 30 controls the first lifting mechanism 53 to move the first inspection head 54 to the preset inspection position, and controls the first inspection head 54 to scan the etching texture inspection area to collect the three-dimensional morphology data of the etching surface of the mold to be inspected, so as to calculate the groove depth and texture spacing.

[0015] Step S4: After step S3 is completed, the controller 30 controls the rotary drive device 11 to drive the turntable 20 to rotate, positioning the mold to be inspected at the defect inspection station 60; the controller 30 controls the defect inspection device 61 to acquire images of the surface defect inspection area according to the inspection motion trajectory, so as to obtain second inspection data and transmit it to the controller 30. The second inspection data includes surface scratches, pinholes, pits, and corrosion defects; preferably, the defect inspection device 61 includes a second lifting mechanism and a second inspection head 64 set on the second lifting mechanism; in step S4, the controller 30 controls the second lifting mechanism to drive the second inspection head 64 to move, and performs partitioned image acquisition of the surface defect inspection area through the second inspection head 64 to stitch together a panoramic image of the etched surface of the mold to be inspected, so as to identify the surface defects and their location, size and type information.

[0016] Step S5: After step S4 is completed, the controller 30 controls the rotary drive device 11 to drive the turntable 20 to rotate, so that the mold to be inspected is positioned at the dimensional tolerance inspection station 70; the controller 30 controls the dimensional tolerance inspection device 71 to scan the cavity dimension and position inspection area according to the inspection motion trajectory, so as to obtain the third inspection data and transmit it to the controller 30. The third inspection data includes the overall dimensions and dimensional tolerance data of the cavity.

[0017] Preferably, the method further includes step S6, after step S5 is completed, the controller 30 controls the rotary drive device 11 to drive the turntable 20 to rotate, and transfers the mold to be inspected to the unloading station after the inspection is completed; at the same time, the controller 30 performs fusion processing on the received first inspection data, second inspection data and third inspection data, and generates an inspection report and qualification judgment result of the mold to be inspected based on standard inspection parameters.

[0018] Preferably, in step S6, the controller 30 uses the built-in data processing module 31 to uniformly register the first detection data, the second detection data, and the third detection data to the same detection reference coordinate system, compares them with the preset standard detection parameters, calculates the deviation values ​​of each parameter, and automatically determines whether the mold to be tested is qualified, so as to generate a standardized detection report and store it for archiving.

[0019] Preferably, the dimensional tolerance detection device 71 includes a third lifting mechanism and a third detection head 74 disposed on the third lifting mechanism; in step S5, the controller 30 controls the third lifting mechanism to drive the third detection head 74 to move, and collects the three-dimensional point cloud data of the mold cavity to be detected through the third detection head 74, and registers and compares the three-dimensional point cloud data with the standard digital model pre-stored in the controller 30 to calculate the overall size and form and position tolerance of the cavity.

[0020] A mold etching inspection device and its method include a machine platform 10, a turntable 20 mounted on the machine platform 10, and a controller 30. The turntable 20 is driven to rotate horizontally by a rotary drive device 11. The turntable 20 is circumferentially spaced with a plurality of clamping mechanisms 12 for clamping workpieces to be inspected. Each clamping mechanism 12 has a clamping position 13 for holding the workpieces to be inspected. Preferably, the clamping mechanism 12 includes a mounting plate disposed on the turntable 20 and a first clamping component 14 and a second clamping component 15 disposed on the mounting plate. The first clamping component 14 and the second clamping component 15 are arranged opposite to each other to form the clamping position 13 for holding the workpieces to be inspected. Both the first clamping component 14 and the second clamping component 15 include a clamping drive component 141 and a clamping block 142. The output end of the clamping drive component 141 is fixedly connected to the clamping block 142 and is used to drive the two sets of clamping blocks 142 to move towards or away from each other to clamp or release the workpieces to be inspected. Through the design of the first clamping component 14 and the second clamping component 15, the size of the clamping position 13 can be changed to adapt to workpieces of various specifications to be inspected, thereby improving versatility. The machine base 10 is provided with a feeding station 40 along the circumference of the turntable 20, a morphology inspection station 50 for inspecting the groove depth and texture spacing of the surface to be inspected by the mold etching, a defect inspection station 60 for inspecting scratches, pinholes, pits and corrosion on the surface of the mold etching, and a dimensional tolerance inspection station 70 for inspecting the overall dimensions of the mold cavity. The machine base 10 is equipped with a morphology detection device 51, a defect detection device 61, and a dimensional tolerance detection device 71 at the corresponding morphology detection station 50, defect detection station 60, and dimensional tolerance detection station 70, respectively. The detection ends of the morphology detection device 51, defect detection device 61, and dimensional tolerance detection device 71 are oriented towards the turntable 20. By setting a turntable and a rotation drive device on the machine base, and integrating the loading station, morphology detection station, defect detection station, and dimensional tolerance detection station in the circumferential direction of the turntable, the mold workpiece only needs to be clamped on the clamping mechanism of the turntable once. It only needs to be rotated horizontally by the turntable to sequentially flow to each detection station to complete the full index detection of texture accuracy, surface quality, and dimensional tolerance. In this way, there is no need to disassemble and position the mold multiple times, avoiding the cumulative positioning error caused by multiple clamping, while shortening the detection process and improving detection efficiency.

[0021] Preferably, the morphology detection device 51 includes a first support frame 52, a first lifting mechanism 53 mounted on the first support frame 52, and a first detection head 54 mounted on the first lifting mechanism 53 for quantitatively detecting the groove depth and texture spacing of the etched surface of the mold to be inspected. When the rotary drive device 11 drives the turntable 20 to rotate horizontally to the morphology detection device 51, the detection end of the first detection head 54 is located above the clamping position 13. The vertical height of the first detection head 54 can be flexibly adjusted by the first lifting mechanism 53. On the one hand, it can adapt to molds of different thicknesses and cavity depths. On the other hand, it can adjust the detection focal length between the first detection head 54 and the etched surface of the mold to ensure the quantitative detection accuracy of the groove depth and texture spacing. At the same time, the detection end of the first detection head 54 is correspondingly positioned above the clamping position 13 to align with the mold to be inspected as it is rotated into place by the turntable 20, avoiding detection position offset, eliminating detection blind spots, and ensuring full coverage and accurate detection of the etched surface of the mold.

[0022] Preferably, the first detection head 54 is a spectral confocal displacement sensor. Using a spectral confocal displacement sensor as the first detection head 54 for morphology detection has two advantages. First, it adopts a non-contact detection method, which avoids direct contact with the etched surface of the mold during the detection process, completely avoiding the risk of scratching the precision etched surface and ensuring the quality of the finished mold. Second, the spectral confocal displacement sensor is not affected by the optical interference of the highly reflective surface of the mold steel, and can quantitatively detect core parameters such as the groove depth and texture spacing of the mold etch, accurately identify texture deviations caused by local over-etching and under-etching, and improve the detection accuracy and reliability of texture precision and consistency.

[0023] Preferably, the defect detection device 61 includes a second support frame 62, a second lifting mechanism 63 mounted on the second support frame 62, and a second detection head 64 mounted on the second lifting mechanism 63 for image acquisition and detection of scratches, pinholes, pits, and corrosion defects on the etched surface of the mold to be inspected. When the rotary drive device 11 drives the turntable 20 to rotate horizontally to the defect detection device 61, the detection end of the second detection head 64 is located above the clamping position 13. The vertical height of the second detection head 64 can be flexibly adjusted through the second lifting mechanism 63 to adapt to the detection distance requirements of different mold specifications, adjust the imaging focal length, and clearly capture micron-level scratches, pinholes, pits, corrosion, and other minute defects on the etched surface of the mold, thereby improving the defect recognition rate. At the same time, the detection end of the second detection head 64 is correspondingly positioned above the clamping position 13 to accurately align with the mold to be inspected after it has been moved into place, ensuring full coverage image acquisition of the etched surface of the mold, avoiding detection blind spots, and ensuring the integrity and accuracy of surface defect detection.

[0024] Preferably, the second detection head 64 is an area array industrial camera, which can realize high-definition area array imaging of the etched surface of the mold. The high-resolution imaging effect can clearly capture micron-level fine scratches, pinholes, pits, corrosion and other surface defects, improving the accuracy of defect identification. At the same time, the area array industrial camera can complete the acquisition of the whole surface image in a single exposure. The imaging speed is fast and can be perfectly adapted to the 20-station turntable-type multi-station cycle inspection process. It is highly matched with the automated flow rhythm of the equipment, further improving the inspection efficiency and ensuring the consistency and stability of batch mold inspection.

[0025] Preferably, the dimensional tolerance detection device 71 includes a third support frame 72, a third lifting mechanism 73 mounted on the third support frame 72, and a third detection head 74 mounted on the third lifting mechanism 73 for detecting the overall dimensions and geometric tolerances of the mold cavity to be inspected. When the rotary drive device 11 drives the turntable 20 to rotate horizontally to the dimensional tolerance detection device 71, the detection end of the third detection head 74 is located above the clamping position 13. The vertical height of the third detection head 74 can be flexibly adjusted through the third lifting mechanism 73 to adapt to molds with different cavity depths and different external dimensions, accurately adjust the detection distance, and ensure the detection accuracy of the overall dimensions and geometric tolerances of the mold cavity. At the same time, by correspondingly setting the detection end of the third detection head 74 above the clamping position 13, it can be accurately aligned with the mold to be inspected after it has been moved into place, realizing the three-dimensional data acquisition of the entire area of ​​the mold cavity, completely covering the dimensional and geometric tolerance detection items of the mold, and ensuring the comprehensiveness and accuracy of the detection results.

[0026] Preferably, the third detection head 74 is a contour scanning sensor, employing a non-contact 3D scanning method. It can quickly acquire complete 3D point cloud data of the mold cavity, calculate the overall dimensional deviation and geometric tolerances such as contour and flatness of the mold, achieving high detection accuracy and speed. The detection process does not require direct contact with the mold cavity, avoiding damage from impacts. It is also perfectly adaptable to the detection of molds with complex curved cavities, fully covering all aspects of mold dimensional and geometric tolerance detection needs, significantly improving the comprehensiveness and accuracy of dimensional inspection. The rotary drive device automatically drives the turntable... After completing the workstation transfer, the clamping mechanism achieves stable clamping and positioning of the mold to be inspected. The rotary drive device and each inspection device are electrically connected to the controller, which can realize the fully automated closed-loop control of the turntable rotation positioning and inspection data acquisition. This eliminates the need for manual operation of multiple devices and repeated mold handling, reducing labor intensity and labor costs. Furthermore, by setting up independent inspection devices at each inspection station, with the inspection ends facing the turntable and corresponding to the stopping position of the mold to be inspected at the clamping position, motion interference and accuracy loss caused by multiple inspection heads sharing the same motion mechanism are avoided. Preferably, the first lifting mechanism 53, the second lifting mechanism 63, and the third lifting mechanism 73 each include a movable plate 55, a vertical plate 56, a vertical drive device 57, and a horizontal drive device 58. The movable plate 55 is mounted on a corresponding support frame. The output end of the vertical drive device 57 is connected to the movable plate 55 to drive the movable plate 55 to reciprocate up and down. The first detection head 54, the second detection head 64, and the third detection head 74 are mounted on the corresponding vertical plate 56. The output end of the horizontal drive device 58 is connected to the vertical plate 56 to drive the vertical plate 56 to reciprocate left and right. The first detection head 54, the second detection head 64, the third detection head 74, the vertical drive device 57, and the horizontal drive device 58 are electrically connected to the controller 30. The vertical drive device 57 drives the movable plate 55 to move up and down reciprocally, thereby adjusting the vertical focal length and detection distance of the detection head to adapt to the detection needs of molds of different specifications. The horizontal drive device 58 drives the vertical plate 56 and the detection head to move left and right reciprocally, which can drive the detection head to complete a horizontal scan along the mold surface. It can achieve full-area, full-coverage detection of large-size mold cavities without adjusting the mold position, completely eliminating detection blind spots and improving the equipment's adaptability to molds of different sizes. At the same time, the vertical drive device 57, the horizontal drive device 58 and the detection head are all electrically connected to the controller 30. The controller 30 can realize the synchronous control of the automated movement of the detection head and data acquisition, eliminating the need for manual adjustment and further improving the automation level of detection and batch consistency of detection accuracy.

[0027] The rotary drive device 11, the morphology detection device 51, the defect detection device 61, and the dimensional tolerance detection device 71 are electrically connected to the controller 30.

[0028] Preferably, the controller 30 has a built-in data processing module 31. The data processing module 31 is used to receive the detection data collected by the morphology detection device 51, the defect detection device 61, and the dimensional tolerance detection device 71 to generate a detection report and a pass / fail judgment result for the mold to be inspected. Through the data processing module 31 built into the controller 30, the full-dimensional detection data collected by the morphology detection device 51, the defect detection device 61, and the dimensional tolerance detection device 71 can be received and integrated simultaneously to realize integrated data processing and analysis of the mold etching texture accuracy, surface quality, and dimensional tolerance. Standardized detection reports and pass / fail judgment results are automatically generated without the need for manual multi-source data sorting, analysis, and pass / fail judgment, reducing the workload of manual labor and completely eliminating the subjective error of manual judgment, ensuring the objectivity and consistency of the detection results. The detection data can be stored and archived simultaneously to realize full-process traceability of mold detection results, perfectly adapting to the quality control management needs of industrial mass production.

[0029] In this embodiment, the principles of morphology detection, defect detection, and dimensional and positional detection are as follows: The principle of morphology detection is based on a spectral confocal displacement sensor. Utilizing the principle of optical dispersion, it accurately calculates the point-by-point height value of the etched surface of the mold by identifying the focusing position of light of different wavelengths, reconstructs the three-dimensional micromorphology of the etched area, and quantifies and collects core parameters such as groove depth, texture spacing, and periodic consistency of the etched texture, thereby achieving accurate detection of texture precision and consistency. Specifically, the spectral confocal displacement sensor incorporates a broadband white light source module, a dispersive objective lens group, a confocal aperture, a spectrometer, a photodetector, and hardware signal processing circuitry. The specific process is as follows: According to the specifications of the mold to be tested, the controller 30 controls the vertical drive device 57 of the first lifting mechanism 53 to drive the movable plate 55 to move up and down, adjusting the spectral confocal displacement sensor to the preset focal length position, ensuring that the textured surface of the mold is completely within the linear range of the sensor; at the same time, through the intermittent stopping of the turntable 20, the textured surface of the mold to be tested is completely aligned with the scanning path of the sensor, locking the detection reference. Then, the controller 30 controls the horizontal drive device 58 of the first lifting mechanism 53 to drive the vertical plate 56 and the sensor to perform uniform horizontal reciprocating scanning along the textured surface of the mold. During the scanning process, the controller 30 collects the horizontal X-axis coordinate of the sensor in real time through the grating ruler of the horizontal drive device 58, and synchronously triggers the sensor to collect the Z-axis height value of the detection point at a fixed sampling frequency. The hardware signal processing circuit binds the X-axis coordinate and the Z-axis height value one by one to generate a two-dimensional contour curve of the textured surface; for large-area textured areas, complete three-dimensional topographic point cloud data is generated by multi-path scanning and stitching. Secondly, the trench depth is calculated by identifying the lowest height value at the bottom of the etched trench and the highest height value at the top of the texture edge; the difference between the two is the actual depth of a single trench. The texture spacing is calculated by identifying the difference in the horizontal X-axis coordinates of two adjacent texture peak points; the consistency detection is to compare the measured values ​​of all trench depths and texture spacings with the preset standard texture parameters in the controller 30, calculate the maximum deviation and standard deviation of the entire area, and complete the quantitative detection of texture consistency. Since the principle of spectral confocalization is not affected by the reflectivity or tilt angle of the measured surface, it can effectively solve the problem of detection failure caused by mirror reflection of mold steel. Even if there is a tilt angle on the sidewall of the etched groove, height data can still be collected. The hardware signal processing circuit of the sensor transmits the collected morphological data and texture parameters to the hardware data processing module 31 of the controller 30 in real time through the industrial Ethernet bus. The module completes the deviation comparison and qualification judgment, and synchronously stores and archives the detection data.

[0030] Defect Detection Principle: The system primarily uses an area array industrial camera, complemented by a supplementary lighting module to eliminate optical interference from the highly reflective surface of the mold steel. It acquires a complete image of the etched surface of the mold through high-definition area array imaging, and distinguishes normal etched textures from abnormal defects such as scratches, pinholes, pitting, and erosion defects through optical features, achieving full-coverage surface quality inspection. The supplementary lighting module consists of a coaxial light source and a ring-shaped multispectral light source. Both the area array industrial camera and the supplementary lighting module are electrically connected to the controller 30. The area array industrial camera incorporates a high-definition fixed-focus lens, a CMOS image sensor, and a hardware image acquisition card, while the supplementary lighting module is equipped with a constant current drive hardware circuit. Specifically, the light emitted by the supplementary lighting module illuminates the textured surface of the mold. The reflected light is focused onto the CMOS image sensor of the area array industrial camera through a high-definition fixed-focus lens. The sensor converts the light signal into an analog electrical signal, which is then converted into a digital image matrix by a hardware image acquisition card. Each pixel in the image corresponds to a grayscale value, and the grayscale value is positively correlated with the intensity of the reflected light. Due to the different reflection characteristics, defect areas and normal texture areas will form a recognizable grayscale difference, providing a basis for defect identification. To address the high reflectivity of mold steel and the periodic texture inherent in the etching process, a dual-light source combination is employed to eliminate imaging interference at its source, ensuring that defects can be identified. A coaxial light source is incident perpendicularly to the mold surface along the camera lens's optical axis, causing specular reflections to return to the lens along the original optical path, eliminating specular reflections on the mold steel surface and preventing pixel overexposure and detail loss caused by reflections. A ring-shaped multispectral light source is incident obliquely at a 45° angle onto the etched surface. For defects such as scratches, pinholes, pits, and etch defects, the light creates diffuse reflection or shadows at the defect locations, resulting in a significant grayscale difference between the defect area and the surrounding normal etched area. Normal periodic etched textures exhibit uniform and regular grayscale changes, clearly distinguishing them from the abrupt grayscale changes of random defects. Before inspection, focusing and attitude adjustment are performed. The controller 30 controls the vertical drive device 57 of the second lifting mechanism 63 to move the movable plate 55 up and down, adjusting the object distance between the camera and the textured surface of the mold so that the textured surface is completely within the depth of field of the lens, obtaining a clear focused image. By intermittently stopping the turntable 20, the textured surface of the mold to be inspected is aligned with the imaging field of view of the camera, locking the imaging reference. For small molds, the camera can complete the image acquisition of the entire textured surface in a single exposure. For large molds, the controller 30 controls the horizontal drive device 58 of the second lifting mechanism 63 to move the camera horizontally, acquiring multiple images in different areas. The controller 30 uses a hardware image stitching circuit, combined with the camera's position grating data, to stitch the multiple images into a complete panoramic image of the textured surface, ensuring no blind spots in the inspection. The hardware implementation process for defect identification is as follows: the image acquisition card transmits digital images in real time to the FPGA hardware image processing module built into the controller 30, and the entire process of defect identification is completed through hardware circuitry. The specific process is as follows: Hardware image preprocessing: The image is preprocessed by a hardware filtering circuit to eliminate image noise and lens distortion, and to extract defect feature signals; Hardware defect feature extraction: The defect areas with abrupt grayscale changes in the image are identified by a hardware edge detection circuit and a threshold segmentation circuit. The quantitative parameters such as the location, contour, size, area, and type of the defect are calculated by a hardware connected component analysis circuit; Defect classification and judgment: The hardware circuit automatically classifies defects into four types based on their morphological characteristics: scratches, pinholes, pits, and erosion, completing the full-item inspection of the surface quality of the mold etching. The FPGA hardware image processing module transmits the quantitative data and defect images of defect detection to the hardware data processing module 31 of the controller 30 in real time. The module compares the data with the preset defect acceptance threshold to complete the acceptance judgment of surface quality and simultaneously stores and archives the detection data and defect images.

[0031] Dimension and position detection principle: Based on a 3D contour scanning sensor, and through the principle of laser triangulation, it quickly acquires 3D point cloud data of the entire area of ​​the mold cavity. The acquired data is registered and compared with a preset standard CAD model to calculate the overall dimensional deviation of the mold cavity, as well as the form and position tolerance parameters such as contour, flatness, and perpendicularity, thereby realizing mold dimension detection; 3D point cloud data is acquired through laser triangulation and registered and compared with a standard CAD model. The 3D line laser contour scanning sensor is electrically connected to the controller 30. The 3D line laser contour scanning sensor has a built-in line laser emitter, polarization optical filter, CMOS imaging camera, and hardware point cloud processing circuit. The laser triangulation relationship is established. The line laser emitter emits a fan-shaped line laser beam to the surface of the mold cavity being measured. The laser forms a continuous laser contour line on the surface of the cavity. Due to the unevenness of the cavity surface, the laser contour line will undergo corresponding deformation. The CMOS imaging camera receives the reflected light from the laser contour line at a preset triangular angle (a fixed angle between the emitter optical axis and the camera optical axis). According to the triangular imaging geometry, the change in the axial height of a certain point on the contour line will cause the pixel position of that point on the camera imaging target surface to shift. The pixel shift amount and the axial height value have a unique linear correspondence. Through factory pre-calibration, a linear mapping relationship between the pixel shift amount and the X or Z axis 3D coordinates is established and solidified in the hardware point cloud processing circuit of the sensor to provide a reference for size detection. After the CMOS camera of the sensor acquires the deformation image of the laser contour line, the hardware point cloud processing circuit extracts the sub-pixel-level edge coordinates of the contour line in real time. It calls the pre-calibrated mapping relationship to calculate the X-axis horizontal coordinate and Z-axis axial height coordinate of all points on the entire laser contour line. Combined with the Y-axis longitudinal displacement data during the scanning process, complete three-dimensional point cloud data can be generated to meet the high-precision dimensional detection requirements of the mold cavity. Before detection, the range is calibrated and the reference is aligned. The controller 30 controls the vertical drive device 57 of the third lifting mechanism 73 to drive the movable plate 55 to move up and down, adjusting the distance between the sensor and the mold cavity so that the cavity surface is completely within the linear range of the sensor. By intermittently stopping the turntable 20, the reference surface of the cavity of the mold to be detected is aligned with the scanning path of the sensor, and the detection reference is locked. The full cavity 3D point cloud acquisition is achieved by the controller 30 controlling the transverse drive device 58 of the third lifting mechanism 73 to drive the sensor to perform uniform longitudinal scanning motion along the mold cavity. During the scanning process, the controller 30 collects the Y-axis longitudinal coordinate of the sensor in real time through the grating ruler of the transverse drive device 58, and synchronously triggers the sensor to collect the X or Z axis coordinate of the laser contour line at a fixed frequency. The hardware point cloud processing circuit binds the X or Y or Z three-axis coordinates one by one and splices them to generate complete high-density 3D point cloud data of the mold cavity, which fully covers all feature surfaces and structures of the cavity. The hardware calculation process for dimensions and geometric tolerances involves the sensor's hardware point cloud processing circuit transmitting the 3D point cloud data to the hardware geometry calculation module built into the controller 30 in real time. The specific process is as follows: Point cloud preprocessing and reference registration: invalid noise points in the point cloud are removed by hardware denoising circuit. Then, the measured 3D point cloud is aligned with the standard CAD model of the mold stored in the controller 30 by using the reference hole and reference plane of the mold to unify the detection reference and eliminate the detection error caused by clamping deviation; Overall size calculation: the boundaries of key features such as length, width and depth of the cavity are fitted by hardware geometric fitting circuit to calculate the size deviation between the measured size and the standard CAD model; Form and position tolerance calculation is performed through hardware geometric calculation circuit to quantify the form and position tolerance of the mold; flatness is fitted to the cavity reference plane and the difference between the maximum and minimum distances from all point clouds to the reference plane is calculated; profile is calculated to determine the maximum normal deviation from the measured point cloud to the standard CAD model surface; perpendicularity or parallelism is fitted to the measured feature surface and the reference feature surface and the deviation of the normal angle between the two surfaces is calculated; position is fitted to the center coordinates of the measured feature and the deviation value from the standard theoretical coordinates is calculated. The controller 30 is a PLC controller or an industrial control host. The controller 30 has a built-in FPGA hardware image processing module, hardware geometry calculation module, and data processing module. The human-machine interface of the controller is fixed on the front end of the machine. The operator can input detection parameters, view real-time detection data, and retrieve historical detection reports through the touch screen. In particular, the controller 30 uses hardware trigger signals to ensure that the sampling frequency of the sensor contour line is perfectly matched with the movement speed of the horizontal drive device 58, ensuring uniform point cloud density and no data omission. For deep cavity molds, the height of the sensor can be adjusted in real time by the vertical drive device 57 to ensure that the features at the bottom of the deep cavity can also be completely collected. The hardware geometry calculation module transmits the dimensional deviation and geometric tolerance data to the hardware data processing module 31 of the controller 30 in real time. The module compares the data with the preset tolerance threshold to complete the qualification judgment of dimensional accuracy and simultaneously stores the archived detection data and the three-dimensional point cloud file. Before leaving the factory, the coordinate system of the three major detection devices is calibrated using standard calibration blocks. The calibration blocks are sequentially transferred to the three detection stations, and the reference feature data of the calibration blocks are collected respectively. The detection coordinate systems of the three detection devices are registered and unified with the station coordinate system of the turntable 20 and the motion coordinate system of the controller 30. The coordinate system transformation parameters are then fixed in the controller 30 to ensure that all data collected by the three detection devices are under the same reference coordinate system. This completely eliminates the reference deviation of multi-station detection, ensures the consistency and comparability of multi-source detection data, and avoids the cumulative error caused by multiple clamping from the root.

[0032] The key design feature of this invention is that it collects detection data of corresponding dimensions through three detection stations and transmits it to the controller in a unified manner. Based on the same turntable coordinate system, it realizes the fusion management of multi-source detection data. In this way, it can comprehensively complete the quality qualification judgment of all indicators of mold etching. In particular, the turntable circular layout is adopted, and each station is evenly arranged along the circumference of the turntable. The overall structure of the equipment is compact and occupies a small area. Secondly, by acquiring global images of the turntable and the mold to be inspected, a unified turntable coordinate system is established to determine the coordinates of any point on the turntable. This provides a unique reference coordinate system for subsequent inspection area division, inspection trajectory generation, and multi-station continuous inspection, thereby solving the problems of inconsistent references and cumulative positioning errors caused by multiple clamping in multi-process inspection. This ensures the consistency of the dimensional inspection data and improves the stability of inspection accuracy. Next, the effective detection area of ​​the mold to be inspected is automatically identified and specifically divided into etching texture detection area, surface defect detection area, and cavity size and position detection area. The coordinate range of each area is locked, and a detection motion trajectory adapted to the corresponding detection requirements is generated based on the coordinate range. In this way, the trajectory matching of different detection items is achieved, avoiding detection blind spots caused by the disconnect between the trajectory and the detection requirements. This adapts to the detection of molds with complex cavities and multi-area etching, ensuring the comprehensiveness and accuracy of the detection. In addition, by adopting a rotary multi-station intermittent transfer scheme, the mold to be inspected can be sequentially transferred to the morphology inspection station, defect inspection station, and dimensional tolerance inspection station simply by rotating the rotary table after being clamped and positioned once. This completes the full inspection of texture accuracy, surface defects, and dimensional tolerances, eliminating the need for multiple disassembly and repositioning of the mold, simplifying the inspection process, and adapting to the inspection needs of industrial batch molds. At the same time, it avoids scratches and bumps on the etched surface caused by repeated manual handling and clamping, effectively reducing the risk of mold scrap and improving production yield. Furthermore, by associating and storing the detection motion trajectory with preset standard detection parameters, when batch-testing molds of the same specification, the pre-stored trajectory and standard parameters can be directly called, eliminating the need for repeated coordinate system calibration and trajectory planning. This shortens the preparation time for batch testing, eliminates batch differences caused by manual operation, and ensures the consistency and repeatability of the test results for the same batch of molds. The test data can be archived and stored synchronously, realizing traceable management of the entire mold testing process to meet the needs of online continuous testing on production lines.

[0033] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for detecting etching patterns on a mold, comprising an instrument for detecting etching patterns on a mold, said instrument including a machine base, a turntable mounted on the machine base, and a controller; characterized in that: Includes the following steps: Step S1: Obtain a global image of the turntable and the mold to be inspected on it, and establish a turntable coordinate system to determine the coordinates of any position on the turntable in the turntable coordinate system; Step S2: The controller identifies the detection area of ​​the mold to be inspected and divides the detection area into an etching texture detection area, a surface defect detection area, and a cavity size and position detection area to determine the coordinate range of the points corresponding to each detection area; the controller generates a detection motion trajectory for each detection area based on the coordinate range of the points and stores the detection motion trajectory in association with the preset standard detection parameters; Step S3: The controller controls the rotary drive device to drive the turntable to rotate, so that the mold to be inspected is positioned at the morphology inspection station; the controller controls the morphology inspection device to scan the etching texture inspection area according to the inspection motion trajectory, so as to obtain the first inspection data and transmit it to the controller. The first inspection data includes the groove depth and texture spacing of the etching. Step S4: After step S3 is completed, the controller controls the rotary drive device to drive the turntable to rotate, so that the mold to be inspected is positioned at the defect inspection station; the controller controls the defect inspection device to collect images of the surface defect inspection area according to the inspection motion trajectory, so as to obtain the second inspection data and transmit it to the controller. The second inspection data includes the collection of surface scratches, pinholes, pits, and corrosion defects. Step S5: After step S4 is completed, the controller controls the rotary drive device to drive the turntable to rotate, so that the mold to be inspected is positioned at the dimensional tolerance inspection station; the controller controls the dimensional tolerance inspection device to scan the cavity dimension and position inspection area according to the inspection motion trajectory, so as to obtain the third inspection data and transmit it to the controller. The third inspection data includes the overall dimensions and dimensional tolerance data of the cavity.

2. The mold etching detection method according to claim 1, characterized in that: It also includes step S6, after step S5 is completed, the controller controls the rotary drive device to drive the turntable to rotate, and transfers the mold to be inspected to the unloading station after the inspection is completed; at the same time, the controller performs fusion processing on the received first inspection data, second inspection data and third inspection data, and generates an inspection report and qualification judgment result of the mold to be inspected based on standard inspection parameters.

3. The mold etching detection method according to claim 1, characterized in that: The morphology detection device includes a first lifting mechanism and a first detection head disposed on the first lifting mechanism; in step S3, the controller controls the first lifting mechanism to move the first detection head to a preset detection position, and controls the first detection head to scan the etching texture detection area to collect three-dimensional morphology data of the etching surface of the mold to be detected, so as to calculate the groove depth and texture spacing.

4. The mold etching detection method according to claim 1, characterized in that: The defect detection device includes a second lifting mechanism and a second detection head mounted on the second lifting mechanism. In step S4, the controller controls the second lifting mechanism to move the second detection head and performs partitioned image acquisition on the surface defect detection area through the second detection head to stitch together a panoramic image of the etched surface of the mold to be inspected, so as to identify the surface defects and their location, size and type information.

5. The mold etching detection method according to claim 1, characterized in that: The dimensional tolerance detection device includes a third lifting mechanism and a third detection head mounted on the third lifting mechanism. In step S5, the controller controls the third lifting mechanism to move the third detection head and collects the three-dimensional point cloud data of the mold cavity to be detected through the third detection head. The three-dimensional point cloud data is then registered and compared with the standard digital model pre-stored in the controller to calculate the overall size and geometric tolerance of the cavity.

6. The mold etching detection method according to claim 2, characterized in that: In step S6, the controller uses its built-in data processing module to uniformly register the first detection data, the second detection data, and the third detection data to the same detection reference coordinate system, compares them with the preset standard detection parameters, calculates the deviation values ​​of each parameter, and automatically determines whether the mold to be inspected is qualified, so as to generate a standardized inspection report and store it for archiving.

7. The mold etching detection method according to claim 1, characterized in that: The standard testing parameters include at least the standard value and tolerance of the etching groove depth, the standard value and tolerance of the texture spacing, the defect acceptance standard, and the overall dimensional tolerance and geometric tolerance standard of the cavity.

8. A mold etching inspection device, characterized in that: It utilizes claim 1 The mold etching detection method according to any one of the following claims includes a feeding station arranged along the circumference of a turntable, a morphology detection station for detecting the groove depth and texture spacing of the surface to be etched on the mold, a defect detection station for detecting scratches, pinholes, pits, and corrosion on the surface of the etched mold, and a dimensional tolerance detection station for detecting the overall dimensions of the mold cavity; the machine tool is respectively equipped with a morphology detection device, a defect detection device, and a dimensional tolerance detection device at the morphology detection station, the defect detection station, and the dimensional tolerance detection station, the detection ends of the morphology detection device, the defect detection device, and the dimensional tolerance detection device are arranged facing the turntable, and the rotation drive device, the morphology detection device, the defect detection device, and the dimensional tolerance detection device are electrically connected to the controller.

9. The mold etching inspection equipment according to claim 8, characterized in that: The turntable is provided with a plurality of clamping mechanisms for clamping the workpiece to be inspected at circumferential intervals, and the clamping mechanisms have clamping positions for holding the workpiece to be inspected. The clamping mechanism includes a mounting plate disposed on a turntable and a first clamping component and a second clamping component disposed on the mounting plate. The first clamping component and the second clamping component are disposed opposite to each other to form a clamping position for clamping the workpiece to be inspected. Both the first clamping component and the second clamping component include a clamping drive and a clamping block. The output end of the clamping drive is fixedly connected to the clamping block and is used to drive the two sets of clamping blocks to move towards or away from each other to clamp or release the workpiece to be inspected.

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