Printing press set position deviation compensation displacement device and displacement compensation method thereof

Abstract

The application discloses a printing machine sleeve position deviation compensation displacement equipment and a displacement compensation method, wherein the equipment comprises a machine body, an ERP system and a mounting displacement system are arranged in the machine body, a display screen and a platform top cover are arranged on the machine body, the platform top cover is hingedly arranged, a code spraying device is arranged on the platform top cover, a scanning mechanism is arranged in the platform top cover, a supporting frame is arranged at the bottom of the machine body, a transparent sample sheet table for placing a test sample sheet is arranged on the supporting frame, a moisture detection hole is arranged on the transparent sample sheet table, the supporting frame is hollowly arranged, drying air holes and water supplement air holes are arranged on the supporting frame, and moisture detection devices, water supplement devices and drying devices are arranged in the supporting frame. According to the application, the sleeve position deviation compensation can be realized by the equipment in the pre-displacement of the sleeve position process of the printing machine, the sleeve position accuracy of the printing process is ensured, and one-time trial production is not needed, so that the production cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of printing equipment technology, and in particular to a printing press registration displacement compensation device and its displacement compensation method. Background Technology

[0002] Registration error is a common problem affecting product quality in the printing and packaging industry. It generally arises from misregistration between two or more printing plates; registration errors will occur whenever multiple printing plates are used. Furthermore, between different stages of printing production, the positions of images on the sheets produced in previous stages may deviate from the reference, and previous processes can easily cause dimensional deformation of the printing substrate. Therefore, even when using the original design files in subsequent stages, registration problems can still occur. This issue significantly impacts print quality and remains a challenging problem across the industry.

[0003] The existing technology involves using the original design files for this process to conduct trial production on the physical printing sample from the previous process. The registration deviation between the graphics and text in this process and the graphics and text in the previous process is manually checked on the trial production sample. Then, the graphic and text positions in this process are modified using design software before production can proceed. The drawbacks of this existing technology are: firstly, it occupies production equipment and the time spent on trial production and plate mounting, which affects production efficiency; secondly, the first trial production plate usually has a registration deviation from the previous physical sample, so the first printing plate cannot be used for production and will be scrapped, increasing auxiliary material costs.

[0004] Therefore, existing technologies need to be improved and enhanced. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a printing press registration deviation compensation displacement device and its displacement compensation method, which can realize the compensation of registration deviation between processes and the deviation compensation of the printing press itself, ensuring the accuracy of registration in the printing process, and eliminating the need for trial production, thereby reducing production costs.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A printing press registration deviation compensation device includes a machine body and a registration deviation compensation module. The machine body is equipped with a display screen and a hinged platform cover. The platform cover is equipped with a coding device and a scanning mechanism. The bottom of the machine body is equipped with a support frame. The support frame is equipped with a transparent sample platform for placing test samples. The transparent sample platform is equipped with a moisture detection hole. The support frame is hollow and is equipped with a drying vent and a water replenishment vent. The support frame also contains a moisture detection device, a water replenishment device, and a drying device.

[0007] Furthermore, the support frame is composed of four trapezoidal baffles, and the support frame is arranged in the form of a trapezoidal platform.

[0008] Furthermore, the scanning mechanism includes scanning guide rails disposed on both sides of the platform top cover, and a scanner is installed between the two scanning guide rails.

[0009] Furthermore, the moisture detection device includes an infrared moisture meter disposed below the transparent sample stage.

[0010] Furthermore, the water replenishment device includes a water storage tank, a return water pipe, and an outlet water pipe. The water storage tank is equipped with a water inlet and an air valve. One end of the outlet water pipe is connected to the water storage tank, and the other end of the outlet water pipe is connected to a high-pressure spray valve for replenishing water to the test sample. One end of the return water pipe is connected to the water storage tank, and the other end of the return water pipe is connected to the outlet water outlet of the support frame.

[0011] Furthermore, the drying device includes a heating wire and a fan.

[0012] Furthermore, the surface of the support frame is provided with a hydrophobic layer.

[0013] A displacement compensation method for a printing press registration deviation compensation device includes the following steps: The test sample on the transparent sample stage is scanned by a scanning mechanism; The test sample is obtained by the registration deviation compensation module, compared with the prepress original file of the test sample, the deviation position and difference points are analyzed, and displayed on the screen. Receive confirmation commands regarding the accuracy of offset positions and difference points, and determine whether the confirmation commands are correct; When the command is confirmed to be correct, the compensation displacement file is output. When the instruction is confirmed to be incorrect, a compensation displacement file is output based on the displacement position and difference points after the manual re-entry of the movement instruction, which is then used for the production of that batch of products.

[0014] Furthermore, the process of obtaining a test sample by the registration deviation compensation module and comparing it with the pre-press original file of the test sample to analyze the offset position and differences includes: screen printing machine error compensation and compensation for the difference in image and text position of the previous process test sample; wherein: The screen printing machine error compensation includes: The screen printing test plate is installed on the screen printing machine, the positional difference between the test sample and the corresponding points of the screen printing test plate is detected, the first error value set is obtained, and the screen printing machine error compensation characteristic file is established. The compensation for the difference in image and text position in the previous process test sample includes: By detecting the positional differences between corresponding points in the previous process sample and the previous process standard document, a second set of error values ​​is obtained, and a previous process sample error compensation characteristic file is established.

[0015] Furthermore, after the registration deviation compensation module obtains the test sample and compares it with the prepress original file of the test sample to analyze the offset position and differences, the process further includes: Obtain the error parameters from the screen printing machine error compensation feature file and the previous process sample error compensation feature file, and compensate the corresponding image feature area coordinate values ​​in the standard file of this process according to each error parameter.

[0016] Furthermore, before installing the screen printing test plate onto the screen printing machine, detecting the positional difference between the test sample and corresponding points of the screen printing test plate, obtaining the first error value set, and establishing the screen printing machine error compensation characteristic file, the process further includes: A screen printing test plate with the maximum printing width and maximum plate size is designed based on the maximum printing area of ​​the screen printing machine. The plate surface is set as the X and Y coordinate planes. The width direction of the test plate is the X-axis, the direction from the gripper edge to the end of the plate is the Y-axis, and the lower left corner of the gripper edge is the origin of the coordinates. The test template is divided into several rectangular regions of the same size in a matrix-like manner within the X and Y coordinate plane, and the geometric center point of each rectangular region and the coordinates of other regions within it are obtained. Further, based on the maximum printing width of the screen printing machine, a screen printing test template with the maximum page size is designed, and the page surface of the test template is set to the X and Y coordinate plane. This step includes: designing a crosshair at the geometric center point of each rectangular region, or designing a crosshair at the geometric center point of each rectangular region corresponding to the "X" shaped position of the test template page.

[0017] Furthermore, the steps of fabricating and installing the screen printing test plate on the screen printing machine, detecting the positional difference between the test sample and the corresponding points of the screen printing test plate, obtaining the first error value set, and establishing the screen printing machine error compensation characteristic file include: the steps of fabricating and installing the screen printing test plate on the screen printing machine for testing include: screen printing red ink, black ink, and dark ink on a transparent printing substrate that is not easily deformed, disassembling and screen printing the screen printing test plate three times, and taking one test sample from each time.

[0018] Further, after the step of uniformly dividing the test panel into several rectangular regions of the same size in a matrix manner in the X and Y coordinate plane, and obtaining the geometric center point of each rectangular region and the coordinates of other regions within it, the method further includes: The screen printing test version file is converted into a grayscale image to form a test standard image, and the test sample is converted into a grayscale image to form a test sample image; Image preprocessing, image region segmentation, and feature extraction were performed using the standard test image and the test sample image to obtain the crosshair features and their coordinate values. The test standard image and the test sample image are registered. The two images are preprocessed, segmented, and feature extracted, and feature coordinate values ​​are calculated and feature numbers are assigned. Then, the coordinate difference of each crosshair feature between the test sample image and the test standard image is calculated. The error value set of multiple test samples and the test standard image is calculated, and the error value set of the screen printing machine is obtained by the mean value of the area, and the error compensation characteristic file of the screen printing machine is established.

[0019] Furthermore, the steps before detecting the positional differences between corresponding points in the previous process sample and the previous process standard document include: feature extraction and positional calibration of the images and text in the previous process standard document and the previous process sample.

[0020] Furthermore, the steps for feature extraction and position calibration of the previous process standard document images and text and the previous process sample images and text include: converting the previous process standard document into a grayscale image to form a previous process standard image, and converting the previous process sample into a grayscale image to form a previous process sample image; Image features and their coordinate values ​​are obtained by image preprocessing, image region segmentation, and feature extraction of the previous process sample image and the previous process standard image; The standard image from the previous process is registered with the sample image from the previous process. The two images are preprocessed, segmented, and feature extracted, and feature coordinate values ​​are calculated and feature numbers are assigned. Then, the coordinate differences of corresponding image features between the sample image from the previous process and the standard image from the previous process are calculated.

[0021] Compared to existing technologies, the printing press registration deviation compensation displacement device provided by this invention includes a machine body registration deviation compensation module. The machine body is equipped with a display screen and a hinged platform cover. The platform cover is equipped with a coding device and a scanning mechanism. A support frame is located at the bottom of the machine body, and a transparent sample platform for placing test samples is mounted on the support frame. The transparent sample platform has a moisture detection hole. The support frame is hollow and has drying and water replenishment ventilation holes. A moisture detection device, a water replenishment device, and a drying device are located inside the support frame. With this invention, the test sample can be tested. The registration deviation compensation module compensates for the registration deviation of the previous process and the positional error of the screen printing master plate based on the data from the test sample. This enables pre-shifting of the registration process during printing, achieving registration deviation compensation, ensuring accurate registration during printing, and eliminating the need for trial production, thus reducing production costs. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the printing press registration deviation compensation displacement device provided by the present invention.

[0024] Figure 2 This is a schematic diagram of the internal structure of the printing press registration deviation compensation displacement device provided by the present invention.

[0025] Figure 3 This is a schematic diagram of the assembly of the drying device and the support frame.

[0026] Figure 4 This is a schematic diagram of the scanning mechanism.

[0027] Figure 5 This is a schematic diagram of the water replenishment device.

[0028] In the diagram: 1. Main body, 2. Display screen, 3. Platform top cover, 4. Inkjet printer, 5. Scanning mechanism, 6. Support frame, 7. Transparent sample table, 8. Moisture detection hole, 9. Drying vent, 10. Water replenishment vent, 11. Moisture detection device, 12. Water replenishment device, 13. Drying device, 14. Platform top cover button, 15. Water replenishment device control button, 16. Drying device control button, 17. Scanning rail, 18. Scanner, 19. Infrared moisture meter, 20. Water tank, 21. Return water pipe, 22. Water outlet, 23. Water inlet, 24. Air valve, 25. High-pressure spray valve, 26. Heating wire, 27. Fan, 28. Test sample. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0030] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0031] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0032] like Figure 1 , Figure 2 and Figure 3 As shown, the printing press registration deviation compensation displacement device provided by the present invention includes a machine body 1 and a registration deviation compensation module. The registration deviation compensation module is responsible for receiving files, managing file versions, downloading files, deleting files, and comparing images and text between files to detect defects and misalignments, and to complete the target file relocation. The machine body 1 is provided with a display screen 2 and a platform top cover 3 hinged to it. The platform top cover 3 is provided with a coding device 4 and a scanning mechanism 5 inside the platform top cover 3. The scanning mechanism 5 can acquire grayscale images. The bottom of the machine body 1 is provided with a support frame 6. The support frame 6 is equipped with a transparent sample table 7 for placing test samples 28. The transparent sample table 7 is provided with a moisture detection hole 8. The support frame 6 is hollow and is provided with a drying vent hole 9 and a water replenishment vent hole 10. The support frame 6 is provided with a moisture detection device 11, a water replenishment device 12, and a drying device 13 inside the support frame 6.

[0033] It is understood that the body 1 is equipped with corresponding platform top cover button 14, water replenishment device control button 15, and drying device control button 16. The moisture detection device 11 can detect the moisture content of the test sample 28 on the transparent sample platform 7 through the moisture detection hole 8. The water replenishment device 12 can replenish water to the test sample 28 through the water replenishment vent 10, so that the test sample 28 can maintain good flatness and prevent excessive wrinkles in the test sample 28 from causing large registration deviations. The drying device 13 can dry the space inside the support frame 6 through the drying vent, ensuring that the components are not corroded by moisture.

[0034] Compared with the prior art, in the technical solution of the present invention, the test sample can be tested by the device, and the registration deviation compensation module performs position compensation on the registration deviation of the previous process and the position error of the printing master of the screen printing machine according to the data of the test sample, that is, pre-shifting of the registration process during the printing process of the printing machine can be realized, registration deviation compensation can be achieved, accurate registration in the printing process is ensured, and one trial production is not required, which reduces production cost.

[0035] It should be noted that there are position deviation of the printing master of the printing machine itself and registration deviation between each process during printing, for example, there is deviation between the process of printing blue pigment and the process of printing black pigment. Only by compensating the two deviation values, namely the position deviation of the printing master of the printing machine itself and the registration deviation between each process, can accurate registration in the whole printing process be ensured.

[0036] In an embodiment, as Figure 2 and Figure 3 shows, the support frame 6 is composed of four trapezoidal baffles, and the support frame 6 is arranged in a trapezoidal frustum shape. That is, the baffles are arranged obliquely, which facilitates water backflow when the water replenishing device 12 replenishes water, and prevents water from adhering to the baffles from affecting the operation of other components.

[0037] Further, as Figure 4 shows, the scanning mechanism 5 comprises scanning guide rails 17 arranged on both sides of the platform top cover 3, a scanner 18 is installed between the two scanning guide rails 17, and the scanner 18 can convert an image into a grayscale image.

[0038] Further, as Figure 2 shows, the moisture detection device 11 comprises an infrared moisture meter 19 arranged below the transparent sample table 7, with the model of Furbs FBS-300, and the infrared moisture meter 19 can measure the moisture content of the test sample 28. It should be noted that the moisture detection device 11 is assembled in a sealed manner, and the outer surface of the spare parts is treated with a hydrophobic coating to avoid water droplet adhesion. The sensor signal of the moisture detection device 11 is connected to the integrated equipment, and can be directly stored, processed and analyzed at the computer end.

[0039] Further, as Figure 2 and Figure 5As shown, the water replenishment device 12 includes a water storage tank 20, a return water pipe 21, and a water outlet pipe 22. The water storage tank 20 is equipped with a water inlet 23 and an air valve 24. One end of the water outlet pipe 22 is connected to the water storage tank 20, and the other end of the water outlet pipe 22 is connected to a high-pressure spray valve 25 for replenishing water to the test sample. One end of the return water pipe 21 is connected to the water storage tank 20, and the other end of the return water pipe 21 is connected to the water outlet of the support frame 6. That is, the backflow water on the baffle can flow into the water storage tank 20 through the return water pipe 21.

[0040] Furthermore, such as Figure 3 As shown, the drying device 13 includes a heating wire 26 and a fan 27. The fan 27 blows the heat from the heating wire 26 into the interior of the support frame 6, keeping the air inside the support frame 6 dry and maintaining a relative humidity of 60% ± 5%. The test sample 28 is placed on the transparent sample stage 7 for moisture detection, which can test the relationship between different moisture contents and paper bending.

[0041] Preferably, the surface of the support frame 6 is provided with a hydrophobic layer to prevent water droplets from sticking.

[0042] The displacement compensation method for the printing press registration deviation compensation displacement device provided by the present invention includes the following steps: The test sample on the transparent sample stage is scanned by a scanning mechanism; The test sample is obtained by the registration deviation compensation module, compared with the prepress original file of the test sample 28, the deviation position and difference points are analyzed, and displayed on the screen. Receive confirmation commands regarding the accuracy of offset positions and difference points, and determine whether the confirmation commands are correct; When the command is confirmed to be correct, the compensation displacement file is output. When the instruction is confirmed to be incorrect, a compensation displacement file is output based on the displacement position and difference points after the manual re-entry of the movement instruction, which is then used for the production of that batch of products.

[0043] Furthermore, before the step of obtaining the test sample by the registration deviation compensation module, comparing and analyzing the offset position and differences with the pre-press original document of the test sample, and displaying the results on the screen, the method further includes: measuring the moisture content of the test sample by a moisture detection device; and adjusting the printing press operating parameters when the moisture content of the test sample is abnormal. This could include adjusting the subsequent raw material arrival time, adjusting the temperature and humidity in the material handling workshop, or adjusting the UV lamp energy during processing. Moreover, the product moisture data is directly related to the current deformation amount and can be directly linked to the shift report. In subsequent production management, products with moisture values ​​within this range can be shifted from their original documents in advance.

[0044] Furthermore, before the step of obtaining the test sample by the registration deviation compensation module, comparing and analyzing the offset position and difference points with the prepress original document of the test sample, and displaying it on the screen, the method further includes: measuring the moisture content of the test sample by a moisture detection device; when the moisture content of the test sample is abnormal, replenishing the test sample by a water replenishment device, so that the test sample 28 can maintain good flatness and prevent excessive wrinkles in the test sample 28 from causing large registration deviations.

[0045] Furthermore, the process of obtaining a test sample by the registration deviation compensation module and comparing it with the pre-press original file of the test sample to analyze the offset position and differences includes: screen printing machine error compensation and compensation for the difference in image and text position of the previous process test sample; wherein: The screen printing machine error compensation includes: The screen printing test plate is installed on the screen printing machine, the positional difference between the test sample and the corresponding points of the screen printing test plate is detected, the first error value set is obtained, and the screen printing machine error compensation characteristic file is established. The compensation for the difference in image and text position in the previous process test sample includes: By detecting the positional differences between corresponding points in the previous process sample and the previous process standard document, a second set of error values ​​is obtained, and a previous process sample error compensation characteristic file is established.

[0046] It is understood that the screen printing machine error compensation characteristic file is the error value generated by the screen printing machine itself during master printing, and the previous process sample error compensation characteristic file is the error value generated by the registration deviation when registering between processes.

[0047] Furthermore, after the registration deviation compensation module obtains the test sample and compares it with the prepress original file of the test sample to analyze the offset position and differences, the process further includes: Obtain the error parameters from the screen printing machine error compensation feature file and the previous process sample error compensation feature file, and compensate the corresponding image feature area coordinate values ​​in the standard file of this process according to each error parameter.

[0048] Furthermore, before installing the screen printing test plate onto the screen printing machine, detecting the positional difference between the test sample and corresponding points of the screen printing test plate, obtaining the first error value set, and establishing the screen printing machine error compensation characteristic file, the process further includes: A screen printing test plate with the maximum printing width and maximum plate size is designed based on the maximum printing area of ​​the screen printing machine. The plate surface is set as the X and Y coordinate planes. The width direction of the test plate is the X-axis, the direction from the gripper edge to the end of the plate is the Y-axis, and the lower left corner of the gripper edge is the origin of the coordinates. The test version is divided into several rectangular regions of the same size in a matrix evenly in the X and Y coordinate plane. The geometric center point of each rectangular region and the coordinates of other regions inside it are obtained. Then, the positioning deviation compensation module uses the obtained coordinate information to test and compare the position error.

[0049] Furthermore, the step of designing a screen printing test plate with the maximum page size based on the maximum printing area of ​​the screen printing machine, and setting the page of the test plate as the X and Y coordinate plane, includes: designing a cross mark at the geometric center point of each of the rectangular areas, or designing a cross mark at the geometric center point of each of the rectangular areas corresponding to the "rice" shaped position of the page of the test plate.

[0050] It is understandable that, assuming the maximum dimensions of the screen printing test template are A and B, the dimensions of the rectangular areas are a and b, respectively, which are proportional scalings of the maximum dimensions. The X and Y coordinates of the crosshairs at the geometric center points of each corresponding rectangular area can then be represented by (a / 2, 3a / 2, 5a / 2, …, Aa / 2) and (b / 2, 3b / 2, 5b / 2, …, Bb / 2), respectively.

[0051] Furthermore, the steps of fabricating and installing the screen printing test plate on the screen printing machine, detecting the positional difference between the test sample and the corresponding points of the screen printing test plate, obtaining the first error value set, and establishing the screen printing machine error compensation characteristic file include: the steps of fabricating and installing the screen printing test plate on the screen printing machine for testing include: screen printing red ink, black ink, and dark ink on a transparent printing substrate that is not easily deformed, disassembling and screen printing the screen printing test plate three times, and taking one test sample from each time.

[0052] The details of the screen printing test plate making and mounting are as follows: Screen stretching requirements: Use 350 mesh screen, set the stretching tension to 24 N / cm, stabilize for at least 15 minutes before applying the screen adhesive, and trim any excess edges after drying. During the stretching process, use a tension meter to measure the tension at 5 points on the screen surface. After the adhesive is completely dry, let it sit for 24 hours. Use a rectangular squeegee with a hardness of approximately Shore A 75. The length of the squeegee should extend 20 mm beyond the screen image at both ends, and a distance should be maintained between its horizontal edge and the inner edge of the screen frame. Secure the screen frame naturally during mounting, without applying tension or pressure to the frame using screws.

[0053] Further, after the step of uniformly dividing the test panel into several rectangular regions of the same size in a matrix manner in the X and Y coordinate plane, and obtaining the geometric center point of each rectangular region and the coordinates of other regions within it, the method further includes: The screen printing test version file is converted into a grayscale image to form a test standard image, and the test sample is converted into a grayscale image to form a test sample image; Cross mark features and their coordinate values are obtained through image preprocessing, image region segmentation and feature extraction performed on the test standard image and the test sample image; Registering the test standard image with the test sample image, performing preprocessing, region segmentation and feature extraction on the two images, calculating feature coordinate values and numbering features, and then calculating coordinate differences of corresponding cross mark features between the test sample image and the test standard image; Collecting and calculating error values of a plurality of said test samples relative to said test standard image, obtaining a screen printer error value set through region averaging, and establishing a screen printer error compensation characteristic file.

[0054] It should be noted that, according to two ways of dividing the planar rectangular region of the screen printing test plate, the first way is directed at the mode where a cross mark is designed at each rectangular geometric center point of the test layout: coordinate differences at other positions except the cross mark in the rectangular region where each cross mark of the test sample image is located are deemed to be the same as the coordinate difference of the cross mark. The second way is directed at the mode where a cross mark is designed at each rectangular geometric center point of the "meter-shaped" position of the test layout: coordinate differences at other positions except the cross mark in the rectangular region where each cross mark of the test sample image is located are deemed to be the same as the coordinate difference of the cross mark; coordinate differences of other rectangular regions are deemed to be the same as those of the rectangular region at the "meter-shaped" position of which the geometric center point has the shortest straight-line distance to the geometric center point of said other rectangular region; if two or more rectangular regions at the "meter-shaped" position meet the condition at the same time, the coordinate difference of said other rectangular region is the average value of coordinate differences of the two or more qualifying rectangular regions at the "meter-shaped" position. It is specifically expressed as follows: The X and Y coordinate values of cross marks at geometric center points of corresponding rectangular regions in the layout of the screen printing test plate file / test standard image can be respectively represented by: (a / 2, 3a / 2, 5a / 2, …, A-a / 2) and (b / 2, 3b / 2, 5b / 2, …, B-b / 2).

[0055] Assume that the X and Y coordinates of the crosshairs at the geometric center points of the corresponding rectangular areas in the test sample image become [a' / 2, 3a' / 2, 5a' / 2, …, A-a' / 2] and [b' / 2, 3b' / 2, 5b' / 2, …, B-b' / 2] respectively due to screen printing machine errors, where the specific value of a' in each coordinate is determined by the actual printing deformation of the screen printing machine. Then, the positional deviation of the test sample image relative to the test standard image, i.e., the screen printing machine error values ​​ΔXmachine and ΔYmachine, can be represented by: [a / 2-a' / 2, 3a / 2-3a' / 2, 5a / 2-5a' / 2, …, (Aa / 2)-(A-a' / 2)] and [b / 2-b' / 2, 3b / 2-3b' / 2, 5b / 2-5b' / 2, …, (Bb / 2)-(B-b' / 2)] respectively. According to the precision control requirements of screen printing machines, certain threshold limits can be set for △X machine and △Y machine respectively. That is, when △X machine and △Y machine are greater than the threshold, they are considered to be valid screen printing machine error values; when △X machine and △Y machine are less than or equal to the threshold, they are considered to be without error.

[0056] Furthermore, the steps before detecting the positional differences between corresponding points in the previous process sample and the previous process standard document include: feature extraction and positional calibration of the images and text in the previous process standard document and the previous process sample.

[0057] Furthermore, the steps for feature extraction and position calibration of the previous process standard document images and text and the previous process sample images and text include: converting the previous process standard document into a grayscale image to form a previous process standard image, and converting the previous process sample into a grayscale image to form a previous process sample image; Image features and their coordinate values ​​are obtained by image preprocessing, image region segmentation, and feature extraction of the previous process sample image and the previous process standard image; The standard image from the previous process is registered with the sample image from the previous process. The two images are preprocessed, segmented, and feature extracted, and feature coordinate values ​​are calculated and feature numbers are assigned. Then, the coordinate differences of corresponding image features between the sample image from the previous process and the standard image from the previous process are calculated.

[0058] It is understandable that we assume the positional deviation values ​​of the previous process sample images are represented by △X sample and △Y sample, respectively. According to the quality control requirements for screen printing products, certain threshold limits can be set for △X sample and △Y sample. That is, when △X sample and △Y sample > the threshold, they are considered valid screen printing error values; when △X sample and △Y sample ≤ the threshold, they are considered error-free. Therefore, a previous process sample error compensation characteristic file is established.

[0059] In summary, the printing press registration deviation compensation displacement device provided by this invention features an inclined baffle that facilitates water backflow during water replenishment, preventing water from adhering to the baffle and affecting the operation of other components. The scanner converts images into grayscale. The moisture detection device is sealed and its components are coated with a hydrophobic coating to prevent water droplets from adhering. The sensor signal of the moisture detection device is connected to the integrated device, allowing for direct storage, processing, and analysis on a computer. The fan blows heat from the heating wire into the interior of the support frame, keeping the air inside the support frame dry. Compared to existing technologies, this invention's solution can compensate for positional errors in the preceding process and the screen printing machine itself, identifying pre-displacement in the preceding process and compensating for registration deviations. This ensures accurate registration during printing without requiring a trial production run, reducing production costs.

[0060] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the scope of protection of the present invention.

Claims

1. A printing press registration deviation compensation device, characterized in that, The system includes a body (1) and a positioning deviation compensation module. The body (1) is hinged with a display screen (2) and a platform top cover (3). The platform top cover (3) is equipped with a coding device (4) and a scanning mechanism (5) inside the platform top cover (3). The bottom of the body (1) is equipped with a support frame (6). The support frame (6) is equipped with a transparent sample table (7) for placing test samples (28). The transparent sample table (7) is equipped with a moisture detection hole (8). The support frame (6) is hollow. The support frame (6) is equipped with a drying vent (9) and a water replenishment vent (10). The support frame (6) is equipped with a moisture detection device (11) and a water replenishment device (12). 2) and drying device (13); the drying device (13) includes heating wire (26) and fan (27). The fan (27) blows the heat of the heating wire (26) into the interior of the support frame (6), so that the air inside the support frame (6) is kept dry and the relative humidity is kept at 60%±5%. The test sample (28) is placed on the transparent sample table (7) for moisture detection, and the relationship between different moisture contents and paper bending is tested. The registration deviation compensation module compensates for the registration deviation of the previous process and the position error of the screen printing master plate according to the data of the test sample (28), so as to realize the pre-shifting of the registration process in the printing process of the printing machine, that is, registration deviation compensation.

2. The printing press registration deviation compensation displacement device according to claim 1, characterized in that, The support frame (6) is composed of four trapezoidal baffles, and the support frame (6) is arranged in the form of a trapezoidal platform.

3. The printing press registration deviation compensation displacement device according to claim 1, characterized in that, The scanning mechanism (5) includes scanning guide rails (17) arranged on both sides of the platform top cover (3), and a scanner (18) is installed between the two scanning guide rails (17).

4. The printing press registration deviation compensation displacement device according to claim 1, characterized in that, The moisture detection device (11) includes an infrared moisture meter (19) located below the transparent sample stage (7).

5. The printing press registration deviation compensation displacement device according to claim 1, characterized in that, The water replenishment device (12) includes a water storage tank (20), a return water pipe (21), and a water outlet pipe (22). The water storage tank (20) is provided with a water inlet (23) and an air valve (24). One end of the water outlet pipe (22) is connected to the water storage tank (20), and the other end of the water outlet pipe (22) is connected to a high-pressure spray valve (25) for replenishing water to the test sample. One end of the return water pipe (21) is connected to the water storage tank (20), and the other end of the return water pipe (21) is connected to the water outlet of the support frame (6).

6. The printing press registration deviation compensation displacement device according to claim 2, characterized in that, The surface of the support frame (6) is provided with a hydrophobic layer.

7. A displacement compensation method for a printing press registration deviation compensation displacement device as described in any one of claims 1-6, comprising the following steps: The test sample on the transparent sample stage is scanned by a scanning mechanism; The test sample is obtained by the registration deviation compensation module, compared with the prepress original file of the test sample, the offset position and difference points are analyzed, and displayed on the screen. Receive confirmation commands regarding the accuracy of offset positions and difference points, and determine whether the confirmation commands are correct; If the command is confirmed to be correct, the compensation displacement file will be output. When the instruction is confirmed to be incorrect, a compensation displacement file is output for the production of that batch of products based on the offset position and difference points after the manual re-entry of the movement instruction.

8. The displacement compensation method of the printing press registration deviation compensation displacement device according to claim 7, characterized in that, The process involves obtaining the test sample via the registration deviation compensation module, comparing it with the pre-press original file of the test sample, and analyzing the offset position and differences, including: screen printing machine error compensation and compensation for the difference in image and text position in the previous process test sample; wherein: The screen printing machine error compensation includes: The screen printing test plate is installed on the screen printing machine, the positional difference between the test sample and the corresponding points of the screen printing test plate is detected, the first error value set is obtained, and the screen printing machine error compensation characteristic file is established. The compensation for the difference in image and text position in the previous process test sample includes: By detecting the positional differences between corresponding points in the previous process sample and the previous process standard document, a second set of error values ​​is obtained, and a previous process sample error compensation characteristic file is established.

9. The displacement compensation method of the printing press registration deviation compensation displacement device according to claim 7, characterized in that, The process of obtaining a test sample from the registration deviation compensation module, comparing it with the prepress original file of the test sample, and analyzing the offset position and differences, further includes: Obtain the error parameters from the screen printing machine error compensation feature file and the previous process sample error compensation feature file, and compensate the corresponding image feature area coordinate values ​​in the standard file of this process according to each error parameter.

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