A large ink-carrying capacity ceramic anilox roller laser engraving system and an engraving method thereof

Abstract

This invention discloses a laser engraving system and method for a high-ink-capacity ceramic anilox roller, relating to the field of ceramic roller laser engraving, aiming to solve the problems of limited ink capacity and low production efficiency in existing technologies. The system includes a laser head, a ceramic roller, and a cell observation instrument, and also includes modules for cell image acquisition, test point positioning, engraving control, analysis, and sub-scanning planning. The laser head includes a laser, a high-frequency torque motor, etc. The high-frequency torque motor can drive the movement of a reflector to adjust the laser beam trajectory. The method generates anilox data, positions cells and test points, matches laser power to engrave test points, compares data output strategies, and dynamically adjusts the sub-scanning trajectory before engraving. This invention adopts a dual-scanning trajectory, combined with real-time visual feedback to adaptively control laser power and trajectory, to achieve fine cell engraving, improve ink capacity, ink transfer uniformity, and production efficiency, and avoid ceramic damage.

Description

Technical Field

[0001] This invention relates to the technical field of laser engraving on ceramic anilox rollers, and more specifically to a laser engraving system and engraving method for ceramic anilox rollers with large ink capacity. Background Technology

[0002] Ceramic anilox rollers are widely used in printing, coating, calendering and other industries. Professional ceramic anilox roller laser engraving systems are key equipment for processing and manufacturing ceramic anilox rollers. Improving the ink loading capacity and production efficiency of ceramic anilox rollers is the focus and challenge of research on ceramic anilox roller laser engraving technology. There are significant differences in characteristics between ceramic roller engraving and metal roller engraving, mainly due to differences in materials. Specifically, ceramic roller engraving is prone to cracking and slag formation at the engraving points, while metal roller engraving is less prone to such phenomena.

[0003] The basic principle of laser engraving ceramic anilox rollers is to use a focused laser beam to synchronously pulse-engrave the surface of the ceramic roller. Current laser engraving systems for ceramic anilox rollers employ a single-scan trajectory method, meaning that while the ceramic roller rotates, the focused laser beam moves unidirectionally along the roller's axis to scan and engrave the surface. Under current technological conditions, there are two main methods to increase the ink loading capacity of the cells:

[0004] One approach is to increase the laser energy used to strike the cells. This can be achieved through two methods: increasing the laser pulse width and increasing the number of times the laser pulse strikes the same cell. Existing patents CN1994738A and CN100425444C propose a ceramic anilox roller manufacturing method that uses CO2 laser dot matrix engraving to increase the overlap between laser dots, thereby increasing the ink load of the cells. While this can improve ink load to some extent, there are limitations. First, as the laser energy applied to the cells increases, the energy density decreases. Second, because the surface morphology of the cells changes under laser action, the increase in cell depth is not directly proportional to the laser energy. Furthermore, as the laser energy applied to the cells increases, the bottom morphology of the cells becomes rougher, thus affecting the ink transfer performance of the ceramic anilox roller. In addition, increasing the number of laser strikes inevitably leads to a decrease in production efficiency. Therefore, there is a contradiction between increasing the ink load of the ceramic anilox roller and improving production efficiency, making further improvements difficult.

[0005] Secondly, increasing the area of ​​the cells is an option. Existing patents CN1203958C and CN1375393A propose a double-mesh ceramic anilox roller engraving method, which involves inserting small cells at the intersections of standard cells to increase ink load to some extent, but this is very limited. This method uses template processing technology, which limits the shape of the cells that can be processed. Furthermore, this system is complex, difficult to apply in practice, and can also lead to a decrease in production efficiency.

[0006] In summary, existing laser engraving systems face technical bottlenecks when processing high-ink-capacity precision ceramic anilox rollers. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a laser engraving system and method for a ceramic anilox roller with a large ink capacity. The purpose is to overcome the technical bottlenecks in existing technologies, such as limited ink capacity, low production efficiency, damage to ceramic materials, and decreased ink transfer performance caused by macroscopic control of laser energy input or simple changes in the geometric layout of the cells.

[0008] This invention employs a dual-scan trajectory method. The motion trajectory of the focused laser beam relative to the surface of the ceramic roller is a dual-scan trajectory. The main scan trajectory is achieved by a main drive device and a secondary drive device, while the secondary scan trajectory is achieved by a high-frequency torque motor controlling the focused laser beam to reciprocate along the axial direction of the ceramic roller. The power of the focused laser beam is controlled according to the coordinate position of the laser pulse strike point within the cell, thus engraving the surface of the ceramic anilox roller. Combined with an adaptive laser power and trajectory planning strategy based on real-time visual feedback, the laser energy distribution within the cells is precisely and dynamically controlled, thereby effectively improving the ink load, ink transfer uniformity, and production efficiency of the ceramic anilox roller.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A laser engraving system for a high-capacity ceramic anilox roller includes a laser head and a ceramic roller. The laser head is movable along the axial direction of the ceramic roller, and the focused laser beam of the laser head is also movable along the axial direction of the ceramic roller. The ceramic roller is rotatable radially. The laser head is also equipped with a cell observation device. The system further includes:

[0011] The hole image acquisition module acquires the ceramic roller surface image captured by the hole observation instrument as the image to be analyzed;

[0012] The test point localization module locates the hole region based on the image to be analyzed, maps the hole region according to a preset sub-scanning trajectory, and selects several test points located at the edge of the hole region on the scanning trajectory according to a preset sampling strategy; and outputs the theoretical data of each test point, including theoretical spatial coordinates, theoretical hole depth, and theoretical hole diameter.

[0013] The test point engraving control module matches the preset laser power to the test point and engraves the test point according to the laser power.

[0014] The test point analysis module analyzes the actual carving data of each carved test point based on the image to be analyzed. It compares the actual carving data with the theoretical data one by one and judges whether each deviation is within the allowable range according to the preset deviation threshold. If all deviations are within the allowable range, the normal strategy is output. If any deviation exceeds the allowable range, the adjustment strategy and difference details are output.

[0015] The sub-scan planning module dynamically adjusts or confirms the subsequent sub-scan trajectory based on the received strategy.

[0016] Furthermore, the sub-scanning planning module includes a difference type confirmation strategy. The difference type confirmation strategy includes classifying and identifying the difference details, extracting the position deviation value, depth deviation value, and diameter deviation value, determining whether they exceed a preset threshold, and outputting the difference item type. The difference item type includes position deviation only and depth or diameter deviation only.

[0017] Furthermore, the sub-scan planning module includes a dynamic adjustment strategy. This strategy includes: when receiving an adjustment strategy and analyzing the difference type to confirm only positional deviation, hiding the test point in the preset sub-scan trajectory or shifting the preset scan trajectory to cover the test point; when receiving an adjustment strategy and analyzing the difference type to confirm only depth or diameter deviation, selecting a new test point, engraving the new test point according to the corrected laser power, and comparing the data until the actual engraving data matches the theoretical data, hiding the new test point in the preset sub-scan trajectory, and re-engraving the original test point; when receiving a normal strategy, precisely marking the index number of the test point in the preset sub-scan trajectory as hidden, and directly using the unhidden trajectory segment as the actual sub-scan trajectory.

[0018] Furthermore, the dynamic adjustment strategy compares the coordinates of the actual engraving position of the test point with the coordinate range of the preset sub-scanning trajectory using a trajectory matching algorithm. If the actual engraving position falls within the preset trajectory, the index number of the test point in the preset sub-scanning trajectory is marked as hidden, and the marked trajectory is determined as the actual sub-scanning trajectory. If the actual engraving position does not fall within the preset trajectory, the position offset is calculated and the motion trajectory of the focused laser beam is instructed to be translated. The translated trajectory is then determined as the actual sub-scanning trajectory.

[0019] Furthermore, the dynamic adjustment strategy involves reselecting new test points within the edge of the mesh and located on a preset sub-scanning trajectory. Based on the difference between the actual and theoretical depth or diameter, the required laser power correction is calculated in a preset deviation and power correction model. The corrected laser power parameters are then sent to the test point engraving control module to control the laser head to engrave the new test point. The actual engraving data of the new test point is compared again. If the deviation still exceeds the allowable range, the process of re-selecting test points, correcting laser power, engraving, and comparing is repeated until the actual engraving data matches the theoretical data or the deviation is within the allowable range. Then, the index numbers of test points without deviation in the original sub-scanning trajectory are marked as hidden, and the laser power corresponding to the test points without deviation is associated and stored.

[0020] Furthermore, the laser head includes a laser, a collimating lens, a beam splitting and shaping system, a high-frequency torque motor, a reflector, a beam expander, a focusing lens, and a laser displacement sensor. The reflector is mounted on the mover of the high-frequency torque motor. The laser beam generated by the laser is collimated by the collimating lens, then split into multiple beams by the beam splitting and shaping system, shaped and compressed, reflected by the reflector, expanded by the beam expander, and focused by the focusing lens. The laser displacement sensor measures the displacement of the high-frequency torque motor in real time.

[0021] Furthermore, the high-frequency torque motor includes a left guiding magnet, a control coil, a torsion shaft, a bearing, an armature, a right guiding magnet, a permanent magnet, a right guiding magnetic block, a left guiding magnetic block, and a housing. The armature is fixed on the torsion shaft, and the lower end of the torsion shaft is fastened to the housing. A torsion spring is formed from the fastening point to the armature mounting section of the torsion shaft. The control coil is mounted on the armature, and the reflector is mounted on the upper end of the torsion shaft. The left guiding magnet and the armature together form air gaps δ1 and δ3, and the right guiding magnet and the armature together form air gaps δ2 and δ4.

[0022] Furthermore, when no current is input to the control coil, the armature is in a neutral and relatively balanced state, and the lengths of each air gap are the same. When a current of a certain polarity is input to the control coil, the magnetic fields of air gaps δ1 and δ4 are enhanced, while the magnetic fields of air gaps δ2 and δ3 are weakened. The armature rotates in the direction of the enhanced magnetic field until the electromagnetic torque, the elastic torque of the torsion shaft, and the load torque reach equilibrium. When the polarity of the input current is opposite, the armature rotates in the other direction.

[0023] Furthermore, the test point engraving control module has a built-in laser power matching database, which associates different cell shapes, ceramic materials, preset cell depths or diameters with the required laser power parameters. Based on the theoretical depth and theoretical diameter of each test point and its position within the cell, the corresponding laser power parameters are accurately matched from the laser power matching database.

[0024] A laser engraving method for a high-ink-capacity ceramic anilox roller includes the following steps:

[0025] Step S1 generates mesh data based on the parameters set by the user;

[0026] In step S2, the mesh area is located and a preset sub-scanning trajectory is mapped in the ceramic roller surface image captured by the mesh observation instrument according to the mesh data. Several test points located at the edge of the mesh area are selected on the scanning trajectory according to the preset sampling strategy, and the theoretical data of each test point is output. The theoretical data includes theoretical spatial coordinates, theoretical mesh depth and theoretical mesh diameter.

[0027] Step S3 involves matching the preset laser power to the test point and then engraving the test point according to that laser power.

[0028] Step S4: Analyze the actual carving data of each carved test point based on the image to be analyzed. Compare the actual carving data with the theoretical data one by one. Output the normal strategy or adjustment strategy based on the comparison results.

[0029] In step S5, the subsequent sub-scanning trajectory is dynamically adjusted or confirmed according to the received strategy, and the mesh area on the surface of the ceramic roller is engraved with the updated sub-scanning trajectory and laser power.

[0030] The beneficial effects of this invention are: it achieves refined and adaptive control of the laser engraving process of ceramic anilox rollers; the application of dual scanning trajectories, especially the high-frequency reciprocating motion of the sub-scanning trajectory within the cells, greatly increases the flexible distribution capability of laser energy within a single cell; combined with the strategy of dynamically changing laser pulse power with the position of the striking point, the geometry, depth, and bottom morphology of the cells can be more precisely controlled; this solves the problem of cell roughening and nonlinear depth growth caused by simply increasing energy in traditional methods, and significantly improves the ink loading capacity of the cells.

[0031] Meanwhile, the real-time visual feedback and adaptive planning module based on the cell observation instrument can instantly and accurately adjust the laser trajectory and power according to the deviation of the actual engraving effect. This effectively compensates for the complex response of ceramic materials under laser action, avoids ceramic breakage and slag formation, and ensures the engraving accuracy and ink transfer performance of the anilox roller. The iterative correction and trajectory translation mechanism not only ensures the accuracy of engraving but also avoids repeated and ineffective engraving operations, thereby significantly improving production efficiency while increasing ink load. In addition, the engraving of ceramic rollers requires high precision in laser power output. Therefore, by testing the test point during the first cell engraving, it is possible to avoid the inability to find the location and factors of abnormalities when detecting anomalies after the overall engraving is completed. Furthermore, repeated engraving with too low laser power can easily lead to slag formation on the ceramic roller, while excessive laser power can easily cause breakage, thereby reducing engraving accuracy. Therefore, this invention successfully solves the fundamental contradiction between balancing large ink load and high production efficiency while ensuring the integrity of the microstructure of the ceramic material, providing reliable technical support for the manufacture of high-performance ceramic anilox rollers. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the high ink-load precision ceramic anilox roller laser engraving system of the present invention;

[0033] Figure 2 This is a flowchart of the engraving system in this invention;

[0034] Figure 3 This is a schematic diagram of the engraved mesh area, sub-scanning trajectory, and various parameters in this invention;

[0035] Figure 4 This is a schematic diagram of the laser head structure in this invention;

[0036] Figure 5 This is a schematic diagram of the controller in this invention;

[0037] Figure 6 This is a three-dimensional schematic diagram of the high-frequency torque motor in this invention;

[0038] Figure 7 These are comparison images of the engraving effects in this invention.

[0039] Auxiliary markings: 1. Main drive unit; 2. Secondary drive unit; 3. Hole observation instrument; 4. Laser head; 5. Grating ruler; 6. Controller; 7. Router; 8. Computer; 9. Encoder; 10. Ceramic roller; 11. Laser; 12. Raw laser beam; 13. Collimating lens; 14. Beam splitting and shaping system; 15. Reflector; 16. Laser displacement sensor; 17. Beam expander; 18. Focusing lens; 19. Focused laser beam; 20. High-frequency torque motor; 21. Left guide magnet; 22. Control coil; 23. Torsion shaft; 24. Bearing; 25. Armature; 26. Right guide magnet; 27. Left guide magnet block; 28. Permanent magnet; 29. ​​Right guide magnet block. Detailed Implementation

[0040] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Identical components are denoted by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "upper," and "lower" used in the following description refer to directions in the accompanying drawings, and the terms "bottom surface," "top surface," "inner," and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0041] Because existing laser engraving systems suffer from limitations in increasing ink capacity, low production efficiency, damage to ceramic materials, and decreased ink transfer performance when processing high-ink-capacity precision ceramic anilox rollers, this invention designs a laser engraving system and engraving method for high-ink-capacity ceramic anilox rollers, including hardware, system, and method components.

[0042] Hardware components, such as Figure 1 As shown, the system includes a main drive unit 1, a secondary drive unit 2, a hole observation device 3, a laser head 4, a grating ruler 5, a controller 6, a router 7, a computer 8, and an encoder 9. The hole observation device 3 consists of a high-definition CCD and a microscope magnifying glass, and is mounted on the laser head 4. The high-definition CCD is aligned with the surface of the ceramic roller 10. The main drive unit 1 is connected to the ceramic roller 10, driving the ceramic roller 10 to rotate (y-direction). The amplitude drive unit is connected to the laser head 4, dragging the laser head 4 along... x The feed mechanism 2 is connected to the focused laser beam 19 of the laser head 4, driving the focused laser beam 19 along the feed path. x The controller 6 is connected to the laser head 4, the main drive device 1, the auxiliary drive device 2, the grating ruler 5, the router 7, and the computer 8 respectively. The computer 8 stores standard hole image data, various parameters, databases, and control programs.

[0043] like Figure 4As shown, the laser head 4 includes a laser 11, a collimating lens 13, a beam splitting and shaping system 14, a high-frequency torque motor 20, a reflector 15, a beam expander 17, a focusing lens, and a laser displacement sensor 16. The reflector 15 is mounted on the mover of the high-frequency torque motor 20. The original laser beam 12 generated by the laser 11 is collimated by the collimating lens 13, then split into multiple beams by the beam splitting and shaping system 14, shaped and compressed, reflected by the reflector 15, expanded by the beam expander 17, and then focused into a focused laser beam 19 by the focusing lens. The high-frequency torque motor 20 drives the reflector 15 mounted on its mover to reciprocate, thereby driving the focused laser beam 19 along the axial direction of the ceramic roller 10. x The direction of the reciprocating motion forms a secondary scanning trajectory.

[0044] like Figure 6 As shown, the high-frequency torque motor 20 consists of a left magnetic conductor 21, a control coil 22, a torsion shaft 23, a bearing 24, an armature 25, a right magnetic conductor 26, a permanent magnet 28, a right magnetic block 29, a left magnetic block 27, and a housing. The armature 25 is fixed to the torsion shaft 23; the lower end of the torsion shaft 23 ( Figure 6 (At point A) it is fastened to the housing, and the lower end of the torsion shaft 23 extends from the fastening point to the armature 25 mounting section ( Figure 6 The diameter of the spring at point B is 2.8 mm, serving as a high-stiffness torsion spring; the control coil 22 is mounted on the armature 25, the left guide magnet 21 and the armature 25 together form air gaps δ1 and δ3, and the right guide magnet 26 and the armature 25 together form air gaps δ2 and δ4; the reflector 15 is mounted on the upper end of the torsion shaft 23 ( Figure 6 At point C, the permanent magnet 28 generates a polarized magnetic field, putting the armature 25 in its optimal working state. After adjustment, the armature 25 is in a neutral and relatively balanced state when no current is input to the control coil 22, with the lengths of each air gap being consistent. When a current of a certain polarity is input to the control coil 22, a control magnetic field is generated. The control magnetic field and the polarized magnetic field are differentially superimposed, strengthening the magnetic fields of air gaps δ1 and δ4, while weakening those of δ2 and δ3. The force on the armature 25 is no longer balanced. Under the action of the electromagnetic torque, it overcomes the spring torque and load torque of the torsion shaft 23 and rotates at an angle in the direction of magnetic field strengthening until the electromagnetic torque and the spring torque and load torque of the torsion shaft 23 reach equilibrium. When the polarity of the input current is opposite, the armature 25 rotates in the other direction.

[0045] The maximum angular displacement of the high-frequency torque motor 20 is 0.0068 rad, the nonlinearity is less than 0.2%, and the frequency response (-3dB) reaches 23.6 kHz. The hysteresis characteristics of the magnetic material cause the static characteristics of the high-frequency torque motor 20 to have hysteresis, but the hysteresis is small, about 1.5%. The focal length of the focusing lens 18 is 100 mm, and the distance from the reflecting mirror 15 to the beam expander 17 is 150 mm. Therefore, the swing amplitude of the focused laser beam 19 reaches 1.36 mm, which can engrave ceramic anilox rollers with a mesh size of 25 LPI or more. The sub-scanning trajectory is completed synchronously with the main scanning trajectory. Therefore, although each cell needs to be struck by the laser beam multiple times, it does not affect the engraving efficiency. When engraving ceramic anilox rollers with the same ink load, the processing speed of this invention is much higher than that of the single-scanning trajectory method of the prior art.

[0046] In addition, such as Figure 5 As shown, controller 6 consists of a main control unit, a data transmission unit, an output drive unit, and a signal detection unit. The main control unit is an embedded microprocessor system with a DSP as its core, consisting of the DSP and its peripheral interface circuits, timing logic circuits, input interfaces, and output interfaces. It communicates with computer 8 via router 7. The input interface is connected to the signal detection module, and the output interface is connected to the output drive module. The data transmission module is based on an Ethernet data interface and consists of a high-frequency torque motor 20 angular displacement data channel, a laser power data channel, and a data buffer. The high-frequency torque motor 20 angular displacement data channel and the laser power data channel receive data sent by computer 8 in real time via router 7 and temporarily store it in the data buffer. The signal detection module detects the signals of encoder 9 and grating ruler 5 in real time, i.e., the main scanning trajectory. The signal detection module also detects the signal of laser displacement sensor 16 in real time, i.e., the secondary scanning trajectory. The signal detection module also detects the laser power signal in real time. The output drive module consists of a main drive device 1 driver, a secondary drive device 2 driver, a high-frequency torque motor 20 driver, and a laser driver.

[0047] like Figure 7 As shown, where Figure 7 (a) shows the holes sculpted using existing single-scan trajectory technology. Figure 7 (b) shows the cells etched using the dual scanning trajectory technology of this invention. The latter has a smoother bottom, better ink transfer performance, and cells of the same depth can hold more ink.

[0048] System components, such as Figure 2 As shown, it includes a hole image acquisition module, a test point positioning module, a test point engraving control module, a test point analysis module, and a sub-scanning planning module, all installed in computer 8. Figure 2 As shown, where:

[0049] The cell image acquisition module is connected to the controller 6 via a communication interface and receives digital image signals from the cell observer 3. The module performs image preprocessing operations, including grayscale conversion, noise reduction, and image distortion correction, and outputs high-resolution image data of the ceramic roller 10 surface as the image to be analyzed. The image data contains real-time microscopic details of the cell area before, during, or after engraving.

[0050] The test point localization module processes the image to be analyzed output by the hole image acquisition module. This module employs image recognition and pattern matching algorithms, such as feature point-based matching algorithms or deep learning segmentation algorithms, to accurately identify and locate the hole regions on the surface of the ceramic roller 10. After identifying the hole regions, it precisely maps a preset sub-scanning trajectory onto the interior of the hole regions according to a preset geometric model. Subsequently, the module selects several test points located at the edge of the hole regions on the mapped trajectory according to a preset sampling strategy (randomly). The module outputs the theoretical data for each test point, including theoretical spatial coordinates (…). x 'coordinate, y (Coordinates), theoretical hole depth, and theoretical hole diameter.

[0051] The test point engraving control module interacts with controller 6. This module receives test point information from the test point positioning module, including test point coordinates. This module has a built-in laser power matching database or model, established based on extensive experimental data, linking different cell shapes, ceramic material properties, preset cell depths or diameters, and required laser power parameters, such as... Figure 3 As shown in (c), a focused laser beam with a power of 19 is preset. Based on the theoretical depth and diameter requirements of each test point, and its position within the mesh, from... Figure 3 In step (c), the corresponding laser power parameters are precisely matched. The module then sends the matched laser power parameters and the test point engraving command to the controller 6, which precisely controls the laser head 4 to engrave the test point with the matched power.

[0052] The test point analysis module, after the test point engraving control module completes the test point engraving, calls the cell image acquisition module again to acquire the surface image of the ceramic roller 10 containing the engraved test points. This module uses a high-precision three-dimensional image reconstruction and measurement algorithm to analyze the image to obtain the actual engraving data of each engraved test point. The actual engraving data includes the actual spatial coordinates of the test point, the actual cell depth, and the actual cell diameter. Subsequently, this module compares these actual engraving data with the theoretical data output by the test point positioning module one by one, calculates various deviation values, such as coordinate deviation, depth deviation, and diameter deviation, and determines whether each deviation is within the allowable range according to the preset deviation threshold. If all deviations are within the allowable range, a normal strategy is output; if any deviation exceeds the allowable range, an adjustment strategy and detailed difference data are output. The difference details data include the specific deviation items that exceed the threshold and their values.

[0053] The sub-scan planning module receives adjustment or normal strategies and possible detailed difference data from the test point analysis module. Based on the received strategies, this module dynamically adjusts or confirms the subsequent sub-scan trajectory.

[0054] The sub-scan planning module also includes a dynamic adjustment strategy. Based on the information output by the test point analysis module, it performs corresponding sub-scan planning. Specifically, it has built-in data parsing to automatically classify and identify the received difference details, accurately extracting the position deviation value (the difference between actual and theoretical coordinates). x The deviation values ​​are 'direction offset', 'depth deviation' (the difference between actual depth and theoretical depth) and 'diameter deviation' (the difference between actual diameter and theoretical diameter). By comparing these deviation values ​​with preset deviation thresholds one by one, it is determined whether each deviation exceeds the allowable range, thereby clarifying the type of difference. The types of difference include only position deviation, only depth or diameter deviation, and no deviation. Of course, it can also include composite deviation, that is, deviations in position, depth, and diameter. The deviation threshold is a fixed parameter predetermined based on the characteristics of ceramic materials, the accuracy requirements of the mesh, and the stability of the laser engraving process.

[0055] When only positional deviation is considered, the actual engraved position of the test point differs from the theoretical position. x 'The directional deviation exceeds the allowable range, while the depth and diameter deviations are within the allowable range. Prioritize adjusting the position of the sub-scan trajectory to ensure that the trajectory can effectively cover the actual engraving area. The specific adjustment strategy is as follows:'

[0056] Call the trajectory matching algorithm to determine the coordinates of the actual engraving position ( It precisely compares the coordinates of the coordinate system (based on the axial and circumferential coordinates of the ceramic roller) with the coordinate range of the preset secondary scanning trajectory. The preset secondary scanning trajectory is formed by the coordinates of the coordinates of the ceramic roller along the axial and circumferential coordinates. xThe trajectory is composed of reciprocating straight line segments in the direction of travel, and each segment includes its starting point and ending point. x 'coordinate( ),judge Does it fall within the interval [ [Inside, among which] This is the trajectory tolerance margin. This judgment is used to determine whether the actual position falls within the preset sub-scan trajectory.

[0057] If the actual position falls within the preset trajectory, the index number of the test point in the preset sub-scanning trajectory is precisely marked as hidden through the computer software interface. The hiding operation notifies the controller during the subsequent engraving process that when the laser beam moves along the preset trajectory to the position corresponding to the test point, it should precisely skip the laser emission at that point, thereby avoiding repeated engraving at that position and preventing abnormalities in the cell shape. The preset trajectory after marking, that is, the trajectory that does not include the position of the hidden test point, is determined as the actual sub-scanning trajectory.

[0058] If the actual position does not fall within the preset trajectory, first calculate the position offset. Its value is Subsequently, the controller 6 sends a trajectory adjustment command to the high-frequency torque motor 20, which includes the translation direction and translation distance. ,like If it is a positive value, it indicates the direction. x 'Translate in the positive direction; if If the value is negative, it indicates the direction. x 'Negative direction translation; after receiving the command, the high-frequency torque motor 20 precisely adjusts its own motion parameters, thereby driving the focused laser beam 19 to translate synchronously.' The translation operation aims to ensure that the adjusted sub-scan trajectory accurately covers the actual engraving position, and the translated trajectory is then determined as the actual sub-scan trajectory.

[0059] When only depth or diameter deviation is detected, meaning the actual engraving depth or diameter at the test point deviates from the theoretical value beyond the allowable range, while the positional deviation is within the allowable range, the module needs to correct the engraving by rematching the laser power and selecting new test points. The specific correction strategy is as follows:

[0060] New test points are re-selected, and the test point localization and reuse method is invoked. Based on the image to be analyzed in the original hole region (i.e., the etched image), new test points are re-selected within the hole edges and located on the preset sub-scan trajectory. Figure 3As shown in (b), there are many intersections between the sub-scan trajectory and the hole region after mapping. Therefore, a few of these points can be selected for the initial test points, and other test points can be selected for the new test points. Then, based on the difference between the actual and theoretical depth or diameter, the required laser power correction amount is calculated in the preset deviation and power correction model. This model is based on historical laser engraving experimental data and includes depth deviation. (Actual depth minus theoretical depth), diameter deviation (Actual diameter minus theoretical diameter) and laser power correction amount The model establishes the correspondence using methods such as multinomial regression, lookup tables, or neural networks. Based on the difference between the actual and theoretical depth or diameter, the model calculates the required adjustment to the laser power. .

[0061] The corrected laser power parameters are sent to the test point engraving control module to control laser head 4 to engrave new test points, i.e., the corrected laser power parameters. After the engraving is completed, the module receives the actual engraving data of the new test point from the test point analysis module. The actual data of the new test point is compared with the theoretical data again. If the deviation still exceeds the allowable range, the module will repeat the iterative process of re-selecting test points, correcting laser power, engraving and comparison until the actual engraving data is consistent with the theoretical data or the deviation is within the allowable range.

[0062] Once the deviation meets the requirements, the module marks the index number of the qualified test point in the original sub-scan trajectory as hidden. At the same time, it sets the laser power that ultimately enables the successful engraving of the new test point. The index number of the test point is associated with the storage so that if the original test point position needs to be re-engraved later, the optimized power parameter can be directly called. At this time, the part that is not hidden in the preset trajectory is determined as the actual sub-scan trajectory. However, the actual sub-scan trajectory also includes the original test point, which has an engraved point area. Therefore, when the focused laser beam passes through the original test point, the laser power is determined according to the actual engraving data to ensure that the engraving of the original test point meets the predetermined requirements.

[0063] When a normal strategy is received, meaning the test point analysis module determines that the deviation between the actual engraving data and the theoretical data of the test point is within the allowable range, the module does not need to perform any trajectory adjustment or power correction. It directly executes the test point hiding operation. Using computer software, the index number of the test point in the preset sub-scan trajectory is accurately marked as hidden. The hiding operation ensures that in the subsequent sub-scan engraving process, the laser beam only moves along the effective trajectory segment that has not been hidden in the preset trajectory, thereby avoiding redundant engraving and further ensuring the accurate forming of the cells and the engraving efficiency. The preset trajectory segment that has not been hidden is directly used as the actual trajectory of the sub-scan.

[0064] Based on the equipment and system, a corresponding engraving method has been designed. This invention provides a laser engraving method for a large ink-carrying capacity ceramic anilox roller, including the following steps:

[0065] Step S1 generates mesh data based on the parameters set by the user;

[0066] In step S2, the mesh area is located and a preset sub-scanning trajectory is mapped in the image of the ceramic roller 10 surface captured by the mesh observation instrument 3 according to the mesh data. Several test points located at the edge of the mesh area are selected on the scanning trajectory according to the preset sampling strategy, and the theoretical data of each test point is output. The theoretical data includes theoretical spatial coordinates, theoretical mesh depth and theoretical mesh diameter.

[0067] Step S3 involves matching the preset laser power to the test point and then engraving the test point according to that laser power.

[0068] Step S4: Analyze the actual carving data of each carved test point based on the image to be analyzed. Compare the actual carving data with the theoretical data one by one. Output the normal strategy or adjustment strategy based on the comparison results.

[0069] In step S5, the subsequent sub-scanning trajectory is dynamically adjusted or confirmed according to the received strategy, and the mesh area on the surface of the ceramic roller 10 is engraved with the updated sub-scanning trajectory and laser power.

[0070] The motion trajectory of the focused laser beam 19 relative to the surface of the ceramic roller 10 is a dual-scan trajectory, including a main scan trajectory and a secondary scan trajectory. The main scan trajectory is synthesized by the rotation of the ceramic roller 10 and the feeding of the laser head 4, while the secondary scan trajectory is driven by the high-frequency torque motor 20 to move the focused laser beam 19 along... x The mesh is formed by reciprocating motion in one direction, with each hole created by multiple laser pulses. The power of the laser pulses varies depending on the coordinates of the point of impact within the hole. Figure 3 As shown in (a), taking the carving of diamond-shaped holes as an example, the main drive device 1 drives the ceramic roller 10 along the circumferential direction ( y (Towards) rotate, and the auxiliary transmission device 2 drags the laser head 4 along... x The laser beam 19 moves in the direction of the main scanning trajectory relative to the surface of the ceramic roller 10.

[0071] At the same time, the high-frequency torque motor 20 drives the focused laser beam 19 along... x The laser beam 19 reciprocates in a directional motion, scanning and engraving multiple times within each cell, forming a secondary scanning trajectory relative to the surface of the ceramic roller 10; for example... Figure 3 As shown in (b), when the focused laser beam 19 is along the main scanning trajectory in yAfter entering the target mesh area, the carving of the target mesh begins, such as... Figure 3 As shown in (c), during one cycle of the high-frequency torque motor 20, the focused laser beam 19 enters from the left edge of the target hole. At this time, the angular displacement of the high-frequency torque motor 20 is 0, the power of the focused laser beam 19 is 0, the armature 25 of the high-frequency torque motor 20 moves clockwise, and the power of the focused laser beam 19 gradually increases. When the angular displacement of the high-frequency torque motor 20 reaches 25% of the full stroke, the power of the focused laser beam 19 reaches 100%. The high-frequency torque motor 20 continues to move clockwise, and the power of the focused laser beam 19 remains unchanged at 100%. When the high-frequency torque... After the angular displacement of motor 20 reaches 75%, the power of the focused laser beam 19 gradually decreases. When the angular displacement of the high-frequency torque motor 20 reaches 100%, the focused laser beam 19 reaches the right edge of the target cavity, and its power is 0. Subsequently, the armature 25 of the high-frequency torque motor 20 moves counterclockwise, and the focused laser beam 19 scans from the right edge to the left edge of the target cavity. Its power changes accordingly based on the coordinate position of the point of impact within the target cavity. This process is repeated to gradually complete the engraving of the entire cavity. At this time, the focused laser beam 19 moves along the main scanning trajectory... y Move to the top edge of the next hole and begin carving the next hole.

[0072] During the engraving process, the main controller 6 detects signals from the encoder 9 and the grating ruler 5 in real time. The encoder 9 collects the displacement of the focused laser beam 19 along the circumference of the ceramic roller 10, and the grating ruler 5 collects the displacement of the laser head 4 along the axial direction of the ceramic roller 10. These signals serve as feedback signals to control the main scanning trajectory, thereby improving its accuracy. The controller 6 also detects signals from the laser displacement sensor 16 in real time, using these signals as feedback signals to control the secondary scanning trajectory. The laser displacement sensor 16 collects the displacement of the focused laser beam 19 driven by the high-frequency torque motor 20 along the axial direction of the ceramic roller 10, further improving the accuracy of the secondary scanning trajectory. Simultaneously, a cell observation instrument 3, composed of a high-definition CCD and a microscope magnifying glass, samples the engraved cell image data in real time and transmits it to the computer 8. The computer 8 software compares the engraved cell image data with the standard cell image data in real time, adjusting various parameters to the optimal state to ensure that the engraved cells remain consistent with the standard cells. The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments; all technical solutions falling within the scope of the present invention's concept are within its protection. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of this invention should also be considered within the scope of protection of this invention.

Claims

1. A high ink carrying capacity ceramic anilox roller laser engraving system characterized by: The laser head (4) and the ceramic roller (10) are included, the laser head (4) can move along the axial direction of the ceramic roller (10), the focused laser beam (19) of the laser head (4) can move along the axial direction of the ceramic roller (10), the ceramic roller (10) can rotate along its radial direction, and a mesh hole observation instrument (3) is further arranged on the laser head (4). A mesh hole image acquisition module acquires the surface image of the ceramic roller (10) shot by the mesh hole observation instrument (3) as an image to be analyzed. A test point positioning module positions a mesh hole area according to the image to be analyzed, maps in the mesh hole area according to a preset sub-scanning track, and selects a plurality of test points located at the edge of the mesh hole area according to a preset sampling strategy on the scanning track; and outputs the theoretical data of each test point, which includes theoretical spatial coordinates, a theoretical mesh hole depth and a theoretical mesh hole diameter. A test point engraving control module matches a preset laser power according to the test point, and engraves the test point according to the laser power. A test point analysis module analyzes the actual engraving data of each engraved test point according to the image to be analyzed of the engraved test point, compares the actual engraving data with the theoretical data one by one, judges whether each deviation is within the allowable range according to a preset deviation threshold, outputs a normal strategy if all deviations are within the allowable range, and outputs an adjustment strategy and difference detail data if any deviation exceeds the allowable range. A sub-scanning planning module dynamically adjusts or confirms the subsequent sub-scanning track according to the received strategy. The sub-scanning planning module includes a difference type confirmation strategy, which includes classifying and identifying according to the difference detail data, extracting a position deviation value, a depth deviation value and a diameter deviation value, judging whether the values exceed the preset threshold, and outputting a difference item type, which includes only position deviation and only depth or diameter deviation. The sub-scanning planning module includes a dynamic adjustment strategy, which includes hiding the test points in the preset sub-scanning track or covering the test points by translating the preset scanning track when receiving the adjustment strategy and analyzing that the difference type is only position deviation; when receiving the adjustment strategy and analyzing that the difference type is only depth or diameter deviation, new test points are selected, the new test points are engraved according to the corrected laser power and the data comparison is performed until the actual engraving data and the theoretical data are consistent, and the new test points in the preset sub-scanning track are hidden and the original test points are re-engraved; when receiving the normal strategy, the index number of the test point in the preset sub-scanning track is accurately marked as hidden, and the track segment that is not hidden is directly used as the actual sub-scanning track.

2. A high ink capacity ceramic anilox roller laser engraving system according to claim 1, characterized in that: The dynamic adjustment strategy compares the coordinates of the actual engraving position of the test point with the coordinate range of the preset sub-scanning track through a track matching algorithm, if the actual engraving position falls within the preset track, the index number of the test point in the preset sub-scanning track is marked as hidden, and the marked track is determined as the actual sub-scanning track. If the actual engraving position does not fall into the preset track, a position offset is calculated and a motion track of the focused laser beam (19) is instructed to be translated, and the translated track is determined as the actual sub-scanning track.

3. The high ink capacity ceramic anilox roller laser engraving system of claim 1, wherein: The dynamic adjustment strategy reselects new test points within the edge of the net and on the preset sub-scanning track, calculates the laser power correction amount to be adjusted according to the current actual and theoretical depth or diameter difference in the preset deviation and power correction model, and sends the corrected laser power parameter to the test point engraving control module to control the laser head (4) to engrave new test points. The actual engraving data of the new test points is compared again. If the deviation still exceeds the allowed range, the test point reselection, laser power correction, engraving and comparison are repeated until the actual engraving data and the theoretical data are consistent or the deviation is within the allowed range. Then, the index number of the test points in the original sub-scanning track without deviation is marked as hidden, and the corresponding laser power of the test points without deviation is associated and stored.

4. The system of claim 1 or 3, wherein: The laser head (4) comprises a laser (11), a collimating mirror (13), a beam splitting and shaping system (14), a high-frequency torque motor (20), a reflecting mirror (15), a beam expanding mirror (17), a focusing lens and a laser displacement sensor (16). The reflecting mirror (15) is installed on the rotor of the high-frequency torque motor (20). The laser beam generated by the laser (11) is collimated by the collimating mirror (13), split into multiple beams by the beam splitting and shaping system (14), shaped and compressed, reflected by the reflecting mirror (15), expanded by the beam expanding mirror (17), and focused by the focusing lens. The laser displacement sensor (16) measures the displacement of the high-frequency torque motor (20) in real time.

5. A high ink capacity ceramic anilox roller laser engraving system according to claim 4, wherein: The high-frequency torque motor (20) comprises a left magnetic guide (21), a control coil (22), a torsion shaft (23), a bearing (24), an armature (25), a right magnetic guide (26), a permanent magnet steel (28), a right magnetic guide block (29), a left magnetic guide block (27) and a shell. The armature (25) is fixed on the torsion shaft (23), the lower end of the torsion shaft (23) is fastened to the shell, the torsion shaft (23) forms a torsional spring from the fastening point to the armature (25) mounting section, the control coil (22) is installed on the armature (25), the reflecting mirror (15) is installed on the upper end of the torsion shaft (23), the left magnetic guide (21) and the armature (25) jointly form air gaps δ1 and δ3, and the right magnetic guide (26) and the armature (25) jointly form air gaps δ2 and δ4.

6. A high ink capacity ceramic anilox roller laser engraving system according to claim 5, wherein: When the control coil (22) does not input current, the armature (25) is in a neutral and relative balance state, and the lengths of the air gaps are the same. When the control coil (22) inputs current of a certain polarity, the magnetic fields of the air gaps δ1 and δ4 are enhanced, the magnetic fields of the air gaps δ2 and δ3 are weakened, the armature (25) rotates towards the direction of the enhanced magnetic field, and the electromagnetic torque, the elastic torque of the torsion shaft (23) and the load torque reach balance. When the input current polarity is reversed, the armature (25) rotates in the other direction.

7. A high ink capacity ceramic anilox roller laser engraving system according to claim 6, wherein: The test point carving control module is internally provided with a laser power matching database, in which different cell shapes, ceramic materials, preset cell depths or diameters are associated with required laser power parameters. According to the theoretical depth and diameter of each test point and its position in the cell, the corresponding laser power parameters are accurately matched from the laser power matching database.

8. A method of laser engraving a high-ink-volume ceramic anilox roller, characterized by: The method comprises the following steps: S1, generating mesh data according to user-set parameters; S2, locating the cell area in the ceramic roller (10) surface image captured by the cell observation instrument (3) according to the mesh data, mapping the preset sub-scan track, and selecting a plurality of test points located at the edge of the cell area according to the preset sampling strategy on the scan track, and outputting the theoretical data of each test point, including the theoretical spatial coordinates, the theoretical cell depth and the theoretical cell diameter; S3, matching the preset laser power according to the test points, and carving the test points according to the laser power; S4, analyzing the actual carving data of each carved test point according to the to-be-analyzed image of the carved test point, comparing the actual carving data with the theoretical data one by one, and outputting a normal strategy or an adjustment strategy according to the comparison result; S5, dynamically adjusting or confirming the subsequent sub-scan track according to the received strategy, and carving the cell area on the surface of the ceramic roller (10) with the updated sub-scan track and laser power; The S5 step includes a difference type confirmation strategy, which includes classifying and identifying according to the difference detail data, extracting the position deviation value, the depth deviation value and the diameter deviation value, and judging whether they exceed the preset threshold, and outputting the difference item type, which includes only position deviation and only depth or diameter deviation; The S5 step includes a dynamic adjustment strategy, which includes hiding the test points in the preset sub-scan track or covering the test points by translating the preset scan track when receiving the adjustment strategy and analyzing the difference type confirmation as only position deviation; when receiving the adjustment strategy and analyzing the difference type confirmation as only depth or diameter deviation, new test points are selected, the new test points are carved according to the corrected laser power, and data comparison is performed until the actual carving data and the theoretical data are consistent, and the new test points in the preset sub-scan track are hidden, and the original test points are supplemented; When receiving the normal strategy, the index number of the test point in the preset sub-scan track is accurately marked as hidden, and the unhidden track segment is directly used as the actual sub-scan track.

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