A method for calibrating charging matrix of inkjet printer

Abstract

The present invention relates to the field of inkjet printer charging matrix calibration, and more specifically, to a method for calibrating a charging matrix for inkjet printers. The technical solution includes determining a base value for the charging voltage of a single column of ink dots, selecting an ink dot N from the single column as an analysis object, and comprehensively considering the mechanical effects of the first x and last y adjacent ink dots on ink dot N during the inkjet printer printing process. Based on the base value for the charging voltage of the single column of ink dots, calibration experiments are performed to obtain charging voltage calibration values ​​for different combinations of ink dots. Calibration values ​​are then obtained by combining the number of adjacent ink dots before and after ink dot N, and a two-dimensional table T[m][] is established. The calibration values ​​are stored in the two-dimensional table as a standard reference library for charging voltage. During printing, the two-dimensional table is queried based on the valid combinations of ink dots before and after a certain ink dot in a dot matrix character to generate a charging matrix. The present invention is suitable for calibrating a charging matrix for inkjet printers.

Description

Technical Field

[0001] The present invention relates to the field of inkjet printer charging matrix calibration, and in particular to a method for calibrating a charging matrix of an inkjet printer. Background Art

[0002] An inkjet printer is a software-controlled, non-contact device that marks products. It primarily consists of an inkjet coder and ink path system. Electric field deflection continuous inkjet printers use the deflection of charged ink dots in an electric field to print dot matrix characters. During the printing process, the voltage output of the charge matrix, which acts as the charging voltage for the ink dots, directly affects their charge level and trajectory, and thus the overall printing performance of the printer.

[0003] There are two existing methods for generating a charge matrix. The first relies solely on theoretical calculations to obtain the charge matrix, but completely ignores the impact of the interaction between charged ink dots on printing quality. In real-time, under this method, the greater the charge, the greater the deflection of the ink dots, the further they deviate from their intended position, resulting in poorer printing quality.

[0004] Another method is based on the first method, taking into account the mutual influence between charged ink dots, and realizing cross printing of each ink dot in a column by changing the data order in the charging matrix, such as Figure 4 As shown, dots 1, 2, and 3 in a row are printed first, followed by dots 4, 5, and 6, and finally dots 7, 8, and 9. This interleaved printing method, by increasing the spacing between adjacent dots in the second half of their flight paths, can somewhat weaken the interaction between the charged dots. However, the influence between dots in the first half of their flight paths still exists. Furthermore, this method introduces new printing errors, causing the dots printed in multiple batches within a row to not fall in a straight line, thus significantly improving the printing quality. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for calibrating a charging matrix of an inkjet printer, thereby improving the accuracy of printing of the charging matrix of the inkjet printer.

[0006] The present invention adopts the following technical solutions to achieve the above-mentioned purpose. The present invention provides a method for calibrating a charging matrix of an inkjet printer, comprising:

[0007] S1, determining a base value of the charging voltage of a single row of ink dots in a manner that the charging voltage of the single row of ink dots increases linearly and the charging voltage difference between adjacent ink dots is a fixed value;

[0008] S2. Select an ink dot N in a single column of ink dots as the analysis object, and comprehensively consider the mechanical effects of the first x and last y adjacent ink dots of ink dot N on ink dot N during the printing process of the inkjet printer;

[0009] S3, according to the single row ink dot charging voltage base value, through experimental calibration to obtain the charging voltage calibration value under different ink dot combinations, combined with the number of adjacent ink dots before and after the ink dot N, to obtain Calibration value, corresponding to Charging voltage calibration value for various ink dot combinations;

[0010] S4. Create a two-dimensional table, The calibration values ​​are stored in the two-dimensional table as a charging voltage standard reference library;

[0011] S5. When the inkjet printer is printing, the two-dimensional table is queried through the combination of valid ink dots before and after a certain ink dot in the dot matrix character to generate a charging matrix.

[0012] Furthermore, in step S3, obtaining the charge voltage calibration values ​​under different ink dot combinations through experimental calibration specifically includes:

[0013] In the experimental calibration, the actual printing effect of the inkjet printer is used as the basis, and the charging voltage value that best meets the expected printing effect is selected as the calibration value.

[0014] Furthermore, in step S5, querying the two-dimensional table based on the combination of valid ink dots before and after a certain ink dot in the dot matrix character specifically includes:

[0015] First, a dot matrix character is generated through conversion, and the ink dot charging voltage standard library is loaded. Then, the index subscript is determined by the position of the current ink dot in a column and the valid ink dots before and after it. The ink dot charging voltage standard library is queried according to the index subscript to obtain the standard value of the single ink dot charging voltage.

[0016] The beneficial effects of the present invention are:

[0017] This method uses a single ink dot in a column as the center, comprehensively considering the mechanical effects of multiple preceding and succeeding ink dots on the current dot's trajectory. Through practical experimental results, it accurately calibrates the charge voltage value of the current dot for different dot combinations, forming a standard library of charge voltages. This library, used as a basis for generating charge matrix values, significantly improves inkjet printing performance. Furthermore, the resulting standard library significantly saves storage resources compared to traditional methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic structural diagram of a print head for an inkjet printer provided by an embodiment of the present invention;

[0019] Figure 2 Schematic diagram of dot matrix character A provided by an embodiment of the present invention;

[0020] Figure 3 Schematic diagram of the charging matrix corresponding to the dot matrix character A provided in an embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of cross printing provided by an embodiment of the present invention;

[0022] Figure 5 is a schematic diagram of a calibration ink dot combination provided by an embodiment of the present invention;

[0023] Figure 6 This is a flow chart of character charging matrix generation provided by an embodiment of the present invention;

[0024] Figure 7 The present invention provides a flowchart of a method for calibrating a charging matrix of an inkjet printer. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0026] Before describing the solution of the present invention, the present invention first explains the structure of the inkjet printer and the printing principle.

[0027] The structure of the inkjet printer nozzle is as follows Figure 1 As shown, there are nozzles 10, printheads 30, charging electrodes 20, ink dot charge induction coils 40, high-voltage deflection plates 50, and ink dot recovery tubes 60. Ink passes through the high-voltage nozzles to form ink lines, which are then split into ink dots by the action of a crystal oscillator. The control system outputs a charging voltage to the charging electrodes at the appropriate time, causing the ink dots to be charged with static electricity. The charged ink dots then pass through the high-voltage deflection plates, where they are deflected by the electric field. Different amounts of charge on the ink dots lead to different deflection positions. Multiple ink dots at different deflection positions land on an object, forming a matrix array and forming a dot matrix character. Uncharged ink dots remain in the electric field and fall into the recovery tube.

[0028] Before printing, the inkjet printer needs to encode the printed characters and convert them into a charging matrix, such as Figure 2 is the dot matrix character of the letter A, such as Figure 3 is the corresponding charging matrix. Each value in the charging matrix corresponds to the charging voltage value of each ink dot. During the printing process, the control system outputs the values ​​in the charging matrix in column order to charge the ink dots until printing is completed.

[0029] The following is an explanation of the inkjet printer charging matrix calibration method of the present invention.

[0030] The present invention provides a method for calibrating a charging matrix of an inkjet printer, such as Figure 7 As shown, specifically including:

[0031] The base charge voltage for a single row of ink dots is determined by linearly increasing the charge voltage for each row of ink dots and maintaining a fixed charge voltage difference between adjacent dots. For example, if the printer prints a maximum of m dots in a row, then there are m base charge voltage values, where m is an integer greater than 0.

[0032] Select an ink dot N in a single row of ink dots as the analysis object. During the printing process of the inkjet printer, the mechanical effects of the first x and last y adjacent ink dots of ink dot N on ink dot N are comprehensively considered (the front and back ink dots repel each other with ink dot N). According to the basic value of the charging voltage of the single row of ink dots, the charging voltage calibration values ​​under different ink dot combinations are obtained through experimental calibration. Combined with the number of adjacent ink dots before and after ink dot N, the charging voltage calibration values ​​are obtained. Calibration value, corresponding to Charging voltage calibration value for various ink dot combinations;

[0033] During calibration, the actual printing results are used as the basis, and the charging voltage value that best matches the expected printing effect is selected as the calibration value. The values ​​of x and y can be determined based on your needs and are generally greater than or equal to 3. A larger value means more calibration data and a greater improvement in print quality.

[0034] Create a two-dimensional table T[m][ ],Will The calibration values ​​are stored in the two-dimensional table, serving as a reference library for charging voltage standards. During printing, the inkjet printer queries this two-dimensional table based on the combinations of valid ink dots before and after a certain dot in the dot matrix character to generate a charging matrix. This matrix outputs charging voltage information that fully considers the impact of the interaction between ink dots on print quality, significantly improving print quality.

[0035] The following is an explanation with specific data.

[0036] For example, consider a printer printing a maximum of 32 dots in a row. The top dot has a charge voltage of 50, and the base charge voltage for each dot is determined by increasing the voltage by a voltage difference of 36. Ideally, if the interactions between dots are not considered, the charge voltage determined in this way will ensure that the dots are evenly arranged in a row when printed on the surface. However, in reality, the interaction between dots (mutual repulsion) will affect their trajectory, especially for dots with larger offsets and longer trajectories. Therefore, dots with longer trajectories (dots at the end of a row) tend to have poorer print quality.

[0037] Select an ink dot at a certain position and comprehensively consider the impact of the first 3 and last 3 ink dots on its printing quality during the printing process. When the current ink dot is valid, there are 64 combinations based on whether the first and last 6 ink dots are valid (whether they are charged, charged means valid). This means that during the printing process, the current ink dot may face 64 force environments. Through experimental simulation of these 64 ink dot combinations, the current ink dot charging voltage value is adjusted based on the basic value, and the charging voltage value of the current ink dot under each combination is calibrated in turn to obtain 64 charging voltage calibration values ​​of the current ink dot.

[0038] Create a two-dimensional table T

[32]

[64] to store the aforementioned calibration values, such as Figure 5 As shown in the figure, the ink dot numbered 3 among the 32 ink dots is taken as the analysis object, and the valid combinations of the first 3 and last 3 ink dots are: 101 110 (1 represents valid, 0 represents invalid). Assume that in this case, the charging voltage value of ink dot No. 3 obtained through experimental calibration is a, and a is stored at position T[3]

[46] (3 is the serial number of the ink dot in a column, and the binary number 101 110 is converted to decimal as 46). Similarly, all possible valid combinations of the first 3 and last 3 ink dots No. 0-31 are calibrated respectively, and the corresponding charging voltage values ​​are recorded to form a charging voltage standard library.

[0039] like Figure 6 As shown, the ink dot charging voltage standard library can be stored as a standard file. During the conversion of dot matrix characters into a charging matrix, the dot matrix characters are first generated through conversion, and the ink dot charging voltage standard library is loaded. The index subscript is then determined based on the current ink dot's position within a column and the valid ink dots before and after it. The ink dot charging voltage standard library is then queried based on the index subscript to obtain the standard value for the individual ink dot charging voltage. This process is repeated repeatedly to generate a complete charging matrix for the printed information.

[0040] The foregoing description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Rather, the present invention can be used in various other combinations, modifications, and environments and can be modified within the scope of the concept described herein through the above teachings or techniques or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be protected by the appended claims.

Claims

1. A method for calibrating a charging matrix of an inkjet printer, characterized in that: include: S1, determining a base value of the charging voltage of a single row of ink dots in a manner that the charging voltage of the single row of ink dots increases linearly and the charging voltage difference between adjacent ink dots is a fixed value; S2. Select an ink dot N in a single column of ink dots as the analysis object, and comprehensively consider the mechanical effects of the first x and last y adjacent ink dots of ink dot N on ink dot N during the printing process of the inkjet printer; S3, according to the single row ink dot charging voltage base value, through experimental calibration to obtain the charging voltage calibration value under different ink dot combinations, combined with the number of adjacent ink dots before and after the ink dot N, to obtain Calibration value, corresponding to Charging voltage calibration value for various ink dot combinations; S4. Create a two-dimensional table. The calibration values ​​are stored in the two-dimensional table as a charging voltage standard reference library; S5. When the inkjet printer is printing, the two-dimensional table is queried through the combination of valid ink dots before and after a certain ink dot in the dot matrix character to generate a charging matrix.

2. The inkjet printer charging matrix calibration method according to claim 1, characterized in that: In step S3, obtaining the charge voltage calibration values ​​under different ink dot combinations through experimental calibration specifically includes: In the experimental calibration, the actual printing effect of the inkjet printer is used as the basis, and the charging voltage value that best meets the expected printing effect is selected as the calibration value.

3. The inkjet printer charging matrix calibration method according to claim 1, characterized in that: In step S5, querying the two-dimensional table based on the combination of valid ink dots before and after a certain ink dot in the dot matrix character specifically includes: First, a dot matrix character is generated through conversion, and the ink dot charging voltage standard library is loaded. Then, the index subscript is determined by the position of the current ink dot in a column and the valid ink dots before and after it. The ink dot charging voltage standard library is queried according to the index subscript to obtain the standard value of the single ink dot charging voltage.

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