Variable-speed movement inkjet printing method, device, equipment and storage medium for a printing carriage

Abstract

The present invention discloses a variable-speed movement inkjet printing method, device, equipment and storage medium for a printing carriage, relating to the technical field of inkjet printing. The method includes obtaining the flight distance of ink droplets, i.e., the second distance, when the printing carriage performs uniform printing along the X-axis direction, and obtaining the flight distance of ink droplets when the printing carriage ejects ink droplets from the starting printing position, i.e., the first distance; obtaining an inkjet grating adjustment value based on the first distance and the second distance, and correspondingly driving the printing carriage to perform inkjet printing during the variable-speed movement along the X-axis direction. The method adjusts the ejection timing of ink droplets during the variable-speed movement printing process through the inkjet grating adjustment value, so that the interval between the landing points of ink droplets or pixel points during variable-speed printing is uniform and the same as that during uniform printing, thereby ensuring the image printing effect. Since printing is performed during the variable-speed movement stage, the printing efficiency can be significantly improved, the printing productivity can be increased, and the material utilization rate can be enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of inkjet printing, and particularly to a method, device, equipment and storage medium for inkjet printing with a printing carriage moving at variable speeds. Background Art

[0002] In a reciprocating scanning inkjet printing system, printing an image requires the printing carriage to move back and forth multiple times. Among them, the movement of the printing carriage is divided into three stages: acceleration, uniform speed, and deceleration. As Figure 1 shown, the reciprocating scanning inkjet printing equipment controls the printing carriage 1 to move back and forth along the crossbeam 2 and eject ink for printing. The movement direction of the printing carriage is the X-axis direction (or printing direction), and the movement direction of the printing carriage 1 relative to the printing medium 3 is the Y-axis direction (or stepping direction). Assume that the printing carriage moves from left to right along the X-axis direction. During this process, the printing carriage starts to accelerate from a standstill, moves at a uniform speed after reaching the printing area (and ejects ink to print an image during the uniform speed movement), and after leaving the printing area 4, starts to decelerate until it stops. After the printing carriage completes 1 Pass printing (or completes one scan) and moves a certain distance along the Y-axis direction relative to the printing medium, the printing carriage starts the next 1 Pass printing, that is, from right to left, enters the acceleration movement from a standstill state until it reaches the printing area and starts to move at a uniform speed, and decelerates to a stop after leaving the printing area 4, and so on until the printing task is completed.

[0003] The printing carriage needs to reciprocate and scan along the X-axis direction multiple times, and the time spent to complete the entire printing task is relatively long. During the process of the printing carriage reciprocating and scanning along the X-axis direction multiple times, the variable speed movement stage (including acceleration and deceleration) usually cannot perform inkjet printing. The main reason is that the change in speed makes it difficult to control the flight trajectory and landing position of ink droplets. The change in speed may cause uneven intervals between ink droplets, affecting the printing accuracy and the superposition effect of multi-Pass printing, and further affecting the printing quality. Moreover, since the printing carriage cannot perform inkjet printing during the variable speed movement stage (including acceleration movement and deceleration movement), the printing efficiency during the movement of the printing carriage along the X-axis direction is further reduced, and thus the printing productivity is affected. Therefore, it is particularly important to utilize the printing carriage to perform inkjet printing during the variable speed movement stage to improve the printing efficiency of the printing carriage while ensuring the overall printing effect. Summary of the Invention

[0004] In view of this, the embodiments of the present invention provide a method, device, equipment and storage medium for inkjet printing with a printing carriage moving at variable speeds, so as to solve the problem in the prior art that the variable speed movement stage of the printing carriage cannot perform inkjet printing, which affects the printing efficiency and productivity.

[0005] In a first aspect, an embodiment of the present invention provides a method for inkjet printing with variable-speed movement of a printing carriage, the method comprising:

[0006] Obtaining the movement speed corresponding to the starting printing position during the variable-speed movement of the printing carriage along the X-axis direction, denoted as the first speed, where the X-axis direction is the printing direction;

[0007] Obtaining the flight distance of ink droplets when the printing carriage prints at a constant speed along the X-axis direction, denoted as the second distance;

[0008] Obtaining the flight distance of the ink droplets along the X-axis direction when the printing carriage ejects ink droplets from the starting printing position according to the first speed and the second distance, denoted as the first distance;

[0009] Obtaining an inkjet grating adjustment value according to the first distance and the second distance;

[0010] Driving the printing carriage to perform inkjet printing during the variable-speed movement along the X-axis direction according to the inkjet grating adjustment value.

[0011] Preferably, the obtaining the movement speed corresponding to the starting printing position during the variable-speed movement of the printing carriage along the X-axis direction, denoted as the first speed, includes:

[0012] Obtaining the movement speed when the printing carriage performs inkjet printing with uniform movement along the X-axis direction, denoted as the second speed;

[0013] Obtaining the corresponding movement distance when the printing carriage accelerates from rest to the first speed, denoted as the acceleration movement distance;

[0014] Obtaining the acceleration of the printing carriage during variable-speed movement according to the acceleration movement distance and the second speed;

[0015] Determining the starting printing position in the variable-speed movement stage of the printing carriage along the X-axis;

[0016] Obtaining the first speed corresponding to the starting printing position of the printing carriage according to the acceleration.

[0017] Preferably, the obtaining the flight distance of the ink droplets when the printing carriage prints at a constant speed along the X-axis direction, denoted as the second distance, includes:

[0018] Obtaining the two-way calibration value when the printing carriage performs two-way calibration printing along the X-axis direction;

[0019] Obtaining the second distance according to the two-way calibration value.

[0020] Preferably, the obtaining the flight distance of the ink droplets along the X-axis direction when the printing carriage ejects ink droplets from the starting printing position according to the first speed and the second distance, denoted as the first distance, includes:

[0021] Obtain the corresponding vertical movement distance and vertical speed when the ink droplets ejected during the uniform movement of the printing carriage in the X-axis direction fall along the Z-axis direction; wherein the Z-axis direction is perpendicular to the X-axis direction and the Y-axis direction, and the Y-axis direction is the direction in which the printing carriage steps relative to the printing medium;

[0022] Obtain the second ratio of the vertical movement distance and the vertical speed according to the first ratio of the second distance and the second speed;

[0023] Obtain the flight distance of the ink droplets along the X-axis direction when the ink droplets are ejected from the starting printing position according to the first speed and the second ratio, which is the first distance.

[0024] Preferably, the obtaining of the inkjet grating adjustment value according to the first distance and the second distance includes:

[0025] Obtain the reference ink droplet landing point deviation value according to the first distance and the second distance;

[0026] Obtain the number of variable-speed printing pixel points according to the printing width and printing accuracy in the X-axis direction during the variable-speed movement stage;

[0027] Obtain the inkjet grating adjustment value corresponding to each variable-speed printing pixel point according to the reference ink droplet landing point deviation value and the number of variable-speed printing pixel points.

[0028] Preferably, the obtaining of the reference ink droplet landing point deviation value according to the first distance and the second distance includes:

[0029] Obtain the reference ink droplet landing point deviation value according to the following formula: ;

[0030] wherein is the reference ink droplet landing point deviation value, L is the second distance, and m 0 is the first distance.

[0031] Preferably, the obtaining of the inkjet grating adjustment value corresponding to each variable-speed printing pixel point according to the reference ink droplet landing point deviation value and the number of variable-speed printing pixel points includes:

[0032] When the printing carriage is in the acceleration movement, , n = 1, 2,..., h;

[0033] When the printing carriage is in the deceleration movement, , n = 1, 2,..., h.

[0034] wherein, is the inkjet grating adjustment value of the nth variable-speed printing pixel point, is the deviation value of the reference ink drop landing point, and h is the number of variable-speed printing pixels.

[0035] Preferably,

[0036] In a second aspect, an embodiment of the present invention provides an inkjet printing device for variable-speed movement of a printing carriage. The device includes:

[0037] A first speed acquisition module, configured to acquire the movement speed corresponding to the starting printing position during the variable-speed movement of the printing carriage along the X-axis direction, denoted as the first speed, where the X-axis direction is the printing direction;

[0038] A second distance acquisition module, configured to acquire the flight distance of the ink drops when the printing carriage performs uniform printing along the X-axis direction, denoted as the second distance;

[0039] A first distance acquisition module, configured to acquire the flight distance of the ink drops along the X-axis direction when the printing carriage ejects ink drops from the starting printing position according to the first speed and the second distance, denoted as the first distance;

[0040] A grating adjustment value acquisition module, configured to acquire an inkjet grating adjustment value according to the first distance and the second distance;

[0041] A printing module, configured to drive the printing carriage to perform inkjet printing during the variable-speed movement along the X-axis direction according to the inkjet grating adjustment value.

[0042] In a third aspect, an embodiment of the present invention provides an inkjet printing device for variable-speed movement of a printing carriage, including: at least one processor, at least one memory, and computer program instructions stored in the memory. When the computer program instructions are executed by the processor, the method in the first aspect of the above implementation manner is implemented.

[0043] In a fourth aspect, an embodiment of the present invention provides a storage medium, on which computer program instructions are stored. When the computer program instructions are executed by the processor, the method in the first aspect of the above implementation manner is implemented.

[0044] In summary, the beneficial effects of the present invention are as follows:

[0045] The variable-speed motion inkjet printing method, device, equipment and storage medium provided by the embodiments of the present invention obtain the motion speed corresponding to the starting printing position during the variable-speed motion of the printing carriage along the X-axis direction, denoted as the first speed, where the X-axis direction is the printing direction; obtain the flight distance of the ink droplets when the printing carriage prints at a constant speed along the X-axis direction, denoted as the second distance; obtain the flight distance of the ink droplets along the X-axis direction when the printing carriage ejects ink droplets from the starting printing position according to the first speed and the second distance, denoted as the first distance; obtain the inkjet grating adjustment value according to the first distance and the second distance; and drive the printing carriage to perform inkjet printing during the variable-speed motion along the X-axis direction according to the inkjet grating adjustment value. The method adjusts the ejection timing of the ink droplets during the variable-speed motion printing process through the inkjet grating adjustment value, so that the interval between the ink droplet landing points or pixel points during variable-speed printing is uniform and consistent with that during constant-speed printing, thereby ensuring the image printing effect. Since printing is performed during the variable-speed motion stage, the printing efficiency in each PASS printing process can be significantly improved, the printing productivity is increased, and at the same time, the utilization rate of the printing medium can be improved, which is beneficial to reducing the material cost. Description of the Drawings

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings, and all of these are within the protection scope of the present invention.

[0047] Figure 1 It is a schematic structural diagram of reciprocating scanning printing in the background art.

[0048] Figure 2 It is a schematic flowchart of the variable-speed motion inkjet printing method of the printing carriage according to the embodiments of the present invention.

[0049] Figure 3 It is a schematic diagram of the motion curve of the printing carriage according to the embodiments of the present invention.

[0050] Figure 4 It is a schematic diagram of the motion trajectory of the ink droplets when the printing carriage prints at a constant speed according to the embodiments of the present invention.

[0051] Figure 5 It is a schematic diagram of the motion trajectories of the ink droplets when the printing carriage accelerates, moves at a constant speed, and decelerates according to the embodiments of the present invention.

[0052] Figure 6 It is a schematic structural diagram of the variable-speed motion inkjet printing device of the printing carriage according to the embodiments of the present invention.

[0053] Figure 7 It is a schematic structural diagram of the variable-speed motion inkjet printing equipment of the printing carriage according to the embodiments of the present invention. Detailed implementation manners

[0054] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be implemented without some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by showing examples of the present invention.

[0055] It should be noted that, in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, elements defined by the statement "including..." do not exclude the presence of additional identical elements in the process, method, article or device including the said elements.

[0056] Embodiment 1

[0057] The embodiment of the present invention provides a variable-speed movement inkjet printing method for a printing carriage, and this method is applicable to a reciprocating scanning printing system. The reciprocating scanning printing system drives the printing carriage to perform multiple reciprocating movements to complete image printing by applying a driving current to the printing carriage. The movement process of the printing carriage includes three stages: acceleration movement, uniform movement, and deceleration movement. Hereinafter, the acceleration movement and deceleration movement stages are collectively referred to as the variable-speed movement stage. In the existing reciprocating scanning printing system, inkjet printing is not performed during the variable-speed movement stage of the printing carriage to avoid affecting the image printing effect. Because when the printing carriage is in variable-speed movement, the flying speeds of the ink droplets ejected from its nozzles in the X-axis direction at different times are different, and the flying distances from the nozzles to the printing medium are also different. The density between the ink droplet landing points is inconsistent or uneven, affecting the final image printing quality. In the embodiment of the present invention, by utilizing the movement characteristics of the printing carriage in the variable-speed movement stage to adjust the inkjet raster value to drive the printing carriage to perform inkjet printing, the printing efficiency of the printing carriage can be improved while ensuring the overall printing effect.

[0058] Please refer to Figure 2, an embodiment of the present invention provides a method for inkjet printing with a variable-speed moving printing carriage. The method includes the following steps:

[0059] S1: Obtain the moving speed corresponding to the starting printing position during the variable-speed movement of the printing carriage along the X-axis direction, denoted as the first speed, where the X-axis direction is the printing direction;

[0060] S2: Obtain the flying distance of the ink droplets when the printing carriage prints at a constant speed along the X-axis direction, denoted as the second distance;

[0061] S3: Obtain the flying distance of the ink droplets along the X-axis direction when the printing carriage ejects ink droplets from the starting printing position according to the first speed and the second distance, denoted as the first distance;

[0062] S4: Obtain the inkjet grating adjustment value according to the first distance and the second distance;

[0063] S5: Drive the printing carriage to perform inkjet printing during the variable-speed movement along the X-axis direction according to the inkjet grating adjustment value.

[0064] Specifically, the movement curve of the printing carriage along the X-axis direction is as Figure 3 shown. The printing carriage starts to perform uniformly accelerated motion from rest, i.e., when the speed is 0. When the speed reaches V max , it starts to perform uniform motion. After a period of uniform motion, it enters the uniformly decelerated motion stage until the speed is 0. In the embodiment of the present invention, inkjet printing starts during the variable-speed movement stage of the printing carriage, and the starting printing position in the variable-speed movement stage can be determined according to the actual situation. Exemplarily, as Figure 3 shown, the distance between the starting printing position and the stationary point of the printing carriage (the position where the speed of the printing carriage is 0) is S 0 , and the corresponding movement speed of the printing carriage at this time is denoted as the first speed V 0 . Obtain the flying distance of the ink droplets when the printing carriage prints at a constant speed along the X-axis direction, denoted as the second distance. In one embodiment, the second distance here can be calculated through the two-way calibration value obtained by controlling the printing carriage to perform two-way calibration printing during uniform printing. The two-way calibration value is the spacing value of the ink drop landing points after printing ink at the same position during the to-and-fro printing process of the printing carriage during uniform printing. This spacing value is twice the second distance, so the second distance is half of the two-way calibration value. In other embodiments, the uniform flying time of the ink droplets can also be obtained according to the distance between the printing carriage and the printing medium and the acceleration due to gravity, and the corresponding second distance can be obtained according to the uniform flying time of the ink droplets.

[0065] According to the first speed corresponding to the printing carriage at the starting printing position, the flying speed at which the ink droplet sprays out from the nozzle at this position can be known. Combining the flying distance and flying speed of the ink droplet during uniform motion, the flying distance (denoted as the first distance) passed by the ink droplet from the starting printing position to when it lands on the printing medium can be obtained. According to the flying distance of the ink droplet during the variable-speed motion of the printing carriage and the flying distance of the printing carriage during uniform motion, the inkjet grating value is adjusted to obtain the inkjet grating adjustment value. According to the inkjet grating adjustment value, the nozzles in the printing carriage are driven to inkjet, so as to adjust the landing point of the ink droplet to make the ink droplet landing points uniform, thereby improving the image printing quality.

[0066] Preferably, obtaining the motion speed corresponding to the starting printing position during the variable-speed motion of the printing carriage along the X-axis direction, denoted as the first speed, includes:

[0067] Obtaining the motion speed of the printing carriage during uniform motion inkjet printing along the X-axis direction, denoted as the second speed;

[0068] Obtaining the corresponding motion distance when the printing carriage accelerates from rest to the first speed, denoted as the acceleration motion distance;

[0069] Obtaining the acceleration of the printing carriage during variable-speed motion according to the acceleration motion distance and the second speed;

[0070] Determining the starting printing position during the variable-speed motion stage of the printing carriage along the X-axis;

[0071] Obtaining the first speed corresponding to the starting printing position of the printing carriage according to the acceleration.

[0072] Specifically, as Figure 3 shown, let the motion speed of the printing carriage during uniform motion along the X-axis direction be V max , denoted as the second speed, V max can be determined by the operator according to the actual situation or by the printing system according to other relevant printing parameters such as driving current. And the distance traveled by the printing carriage from speed 0 to V max is S max , denoted as the acceleration motion distance. As Figure 1 shown, the acceleration motion distance is actually the distance between the starting point of the printing carriage and the boundary of printing area 4. According to the second speed and the acceleration motion distance, the acceleration a of the printing carriage can be calculated.

[0073] Specifically, according to the formula: (1);

[0074] The acceleration of the printing carriage during the variable-speed motion stage can be obtained. After obtaining the acceleration, knowing that the distance between the starting printing position and the starting point is S 0, the speed corresponding to the starting printing position, i.e., the first speed V, can be obtained. 0 value.

[0075] Preferably, obtaining the flight distance of the ink droplets in the X-axis direction when the printing carriage ejects ink droplets from the starting printing position according to the first speed and the second distance, denoted as the first distance, includes:

[0076] Obtaining the vertical movement distance and vertical speed corresponding to the ink droplets falling in the Z-axis direction when the printing carriage ejects ink droplets during uniform motion in the X-axis direction; wherein the Z-axis direction is perpendicular to the X-axis direction and the Y-axis direction, and the Y-axis direction is the direction in which the printing carriage steps relative to the printing medium;

[0077] Obtaining a second ratio of the vertical movement distance and the vertical speed according to a first ratio of the second distance and the second speed;

[0078] Obtaining the flight distance of the ink droplets in the X-axis direction when ejecting ink droplets from the starting printing position according to the first speed and the second ratio, which is the first distance.

[0079] Specifically, for simplicity of calculation, it is assumed that after the ink droplets leave the nozzle, they maintain uniform motion in the vertical and horizontal directions. The flight distances of the ink droplets in the X-axis direction and the vertical direction (Z-axis direction, perpendicular to the X-axis and Y-axis) after leaving the nozzle are respectively denoted as and (vertical movement distance), and the flight speeds in the X-axis direction and the Z-axis direction are respectively denoted as and (vertical speed), then the following formula can be obtained: (2);

[0080] If the printing carriage is driven to perform two-way printing calibration during uniform motion in the X-axis, then the obtained two-way calibration value k is twice the flight distance (second distance) of the ink droplets during uniform motion printing of the print head. According to formula (2), the second distance or the two-way calibration value k and the speed during uniform motion can be used to calculate result.

[0081] The movement speed of the printing carriage in the X-axis direction when the ink droplets leave the nozzle is the flight speed of the ink droplets in the air. Calculate the flight distance of the ink droplets in the X-axis direction at the starting printing position through formula (2), denoted as m 0 , where , k and values are known, so that the value of m 0 can be obtained, which is the first distance.

[0082] Preferably, obtaining the inkjet grating adjustment value according to the first distance and the second distance includes:

[0083] Obtaining a reference ink drop landing point deviation value according to the first distance and the second distance;

[0084] Obtaining the number of variable-speed printing pixel points according to the printing width and printing accuracy in the X-axis direction during the variable-speed movement stage;

[0085] Obtaining the inkjet grating adjustment value corresponding to each variable-speed printing pixel point according to the reference ink drop landing point deviation value and the number of variable-speed printing pixel points.

[0086] Specifically, obtain the difference between the flight distance of the ink drop at the starting printing position (i.e., the first distance) and the flight distance of the ink drop during uniform motion (the second distance) , where , then , and record this difference as the reference ink drop landing point deviation value. Usually it is a relatively small distance (e.g., 3 pixels), and within this distance, it can be approximately considered that the X-axis movement speed of the printing carriage remains unchanged. As Figure 4 shown, for the first pixel point printed in each pass, only need to adjust the grating position of its inkjet by this distance, and the flight distance of the ink drop corresponding to this pixel point after being ejected from the nozzle can be the same as the flight distance during normal uniform motion, that is, ensure that the ink drop landing point during the variable-speed movement stage is the same as that during uniform motion. Therefore it is the inkjet grating adjustment value corresponding to the first pixel point.

[0087] According to the inkjet grating adjustment value corresponding to the first pixel point, that is, the reference ink drop landing point deviation value, the inkjet grating adjustment values corresponding to other pixel points printed during the variable-speed movement stage can be obtained. The pixel points printed during the variable-speed movement stage are called variable-speed printing pixel points, and the number of variable-speed printing pixel points can be obtained according to the printing width and printing accuracy in the X-axis direction of the printing carriage during variable-speed movement, where the printing width during the variable-speed movement stage is S max - S 0 , assuming the printing accuracy is D dpi, multiplying the printing width converted to inches by the printing accuracy can obtain the number of variable-speed printing pixel points, denoted as h. It should be noted that when the printing carriage moves to the uniform motion stage, the inkjet grating adjustment value must be equal to 0, that is, the inkjet grating value does not need to be adjusted during the uniform motion stage. For simplicity of calculation, divide the inkjet grating adjustment value corresponding to the starting printing position into h equal parts, and during the acceleration stage, the inkjet grating adjustment value corresponding to each printed pixel point decreases . The inkjet grating adjustment value for printing the first pixel point is , the inkjet raster adjustment value for printing the second pixel is …… The inkjet raster adjustment value for the h-th pixel is …… When the printing carriage moves to the uniform speed stage, that is, when printing the (h + 1)-th pixel, the inkjet raster adjustment value is 0.

[0088] In addition, it is worth pointing out that the formula , where n = 1, 2, ……, h; is the inkjet raster adjustment value corresponding to each pixel in the acceleration stage. The first variable-speed printing pixel printed in the acceleration stage is the pixel farthest from the uniform-speed printing pixel, and in the deceleration stage, the first variable-speed printing pixel is the next pixel of the uniform-speed printing pixel. At this time, the inkjet raster adjustment value when reaching the h-th variable-speed printing pixel is , divide the inkjet raster adjustment value into h equal parts. When printing each pixel in the deceleration stage, its corresponding inkjet raster adjustment value increases by . Then the inkjet raster adjustment value of the first variable-speed printing pixel after the printing carriage enters the deceleration stage is , the inkjet raster adjustment value of the second variable-speed printing pixel is , and the inkjet raster adjustment value when reaching the h-th variable-speed printing pixel is , at this time , where n = 1, 2, ……, h.

[0089] Obtain the inkjet raster adjustment value corresponding to each variable-speed printing pixel in the variable-speed printing stage, and adjust the ejection timing of the corresponding ink droplets according to the inkjet raster adjustment value corresponding to each variable-speed printing pixel, so as to adjust the position where the ink droplets ejected during these variable-speed movements land on the printing medium. As Figure 5 shown, they are respectively schematic diagrams of the ink droplet flight trajectories and ink droplet landing points of the printing carriage in the acceleration stage, uniform speed stage and deceleration stage. Among them, in the acceleration stage, m 0 is the flight distance of the ink droplet corresponding to the first variable-speed printing pixel, m 1 is the flight distance of the ink droplet corresponding to the second variable-speed printing pixel ……, in the deceleration stage, m n is the flight distance of the ink droplet corresponding to the first variable-speed printing pixel, m n-1 is the flight distance of the ink droplet corresponding to the second variable-speed printing pixel …… Using the inkjet raster adjustment value makes the intervals between the ink droplet landing points (or pixels) during variable-speed printing uniform and the same as those during uniform-speed printing, thus ensuring the image printing effect. Since printing is carried out during the variable-speed movement stage, the printing efficiency in each PASS printing process can be significantly improved, and the printing productivity is increased.

[0090] In addition to the uneven spacing of ink droplets caused by speed changes, which affects the printing accuracy, changes in other parameters such as ink viscosity and nozzle temperature will also affect the ink droplet ejection speed and flight trajectory. In one embodiment, before driving the printing carriage to perform a printing task according to the obtained inkjet grating adjustment value, the printing carriage can also be driven to perform a test print according to the inkjet grating adjustment value first, to detect whether there is a deviation between the actual landing point and the ideal landing point of the ink droplet. If there is a large deviation, it is necessary to further correct the inkjet grating adjustment value to ensure high printing quality during the speed change stage. The specific steps are as follows:

[0091] Control the printing carriage to eject ink droplets at corresponding positions according to the inkjet grating adjustment value;

[0092] Monitor the flight trajectory and landing position of the ink droplet, and calculate the first distance deviation between the actual landing point and the expected landing point of the ink droplet;

[0093] If the first distance deviation is greater than the first threshold, obtain the nozzle temperature and ink viscosity in the printing carriage;

[0094] Obtain a first correction coefficient according to the first difference between the nozzle temperature and the preset standard temperature, the second difference between the ink viscosity and the preset standard viscosity;

[0095] Adjust the inkjet grating adjustment value according to the first distance deviation and the first correction coefficient to obtain a first corrected grating adjustment value;

[0096] Control the printing carriage to eject ink droplets at corresponding positions according to the first corrected grating adjustment value;

[0097] Monitor the flight trajectory and landing position of the ink droplet, and calculate the second distance deviation between the actual landing point and the expected landing point of the ink droplet;

[0098] If the second distance deviation is less than or equal to the first threshold but greater than the second threshold, obtain a heating coefficient according to the first difference and the second difference, and heat the nozzle according to the heating coefficient so that the third difference between the nozzle temperature and the preset standard temperature is within the preset temperature difference range and the fourth difference between the ink viscosity and the preset standard viscosity is within the preset viscosity difference range;

[0099] Obtain a second correction coefficient according to the third difference and the fourth difference;

[0100] Adjust the inkjet grating adjustment value according to the second distance deviation and the second correction coefficient to obtain a second corrected grating adjustment value;

[0101] Obtain a new inkjet grating adjustment value according to the second corrected grating adjustment value.

[0102] Specifically, before the inkjet printer drives the print carriage to perform the actual printing task according to the inkjet grating adjustment value, a test print is first carried out. The print carriage is controlled to eject ink droplets at the corresponding position according to the inkjet grating adjustment value, and the flight trajectory and landing position of the ink droplets are monitored in real time. By calculating the first distance deviation between the actual landing point and the expected landing point of the ink droplets, it is possible to determine whether the current printing quality meets the requirements. If the first distance deviation is greater than the preset first threshold, it means that the landing point deviation of the ink droplets is relatively large, which may affect the printing effect. At this time, the temperature of the print head in the print carriage and the viscosity data of the ink are further obtained. The print head temperature and ink viscosity are important factors affecting the flight trajectory and landing position of the ink droplets. Too high or too low temperature, too large or too small viscosity will cause changes in the flight speed and landing position of the ink droplets. Next, according to the first difference between the print head temperature and the preset standard temperature, and the second difference between the ink viscosity and the preset standard viscosity, the first correction coefficient is calculated. This correction coefficient is used to preliminarily adjust the inkjet grating adjustment value to compensate for the landing point deviation of the ink droplets caused by the differences in the print head temperature and ink viscosity. Through the first correction coefficient, the first corrected grating adjustment value is generated, and the print carriage is controlled to eject ink droplets at the corresponding position again according to this corrected value.

[0103] Exemplarily, the first correction coefficient is obtained through the following formula: ;

[0104] where ΔT is the first difference, Δη is the second difference, α is the influence coefficient of the print head temperature difference on the correction coefficient, β is the influence coefficient of the ink viscosity difference on the correction coefficient, and α and β can be obtained by fitting experimental data. Exemplarily, if the print head temperature is higher than the standard temperature (ΔT>0), the flight speed of the ink droplets may increase, resulting in the landing point being ahead. At this time, α is negative, which is used to reduce the inkjet grating adjustment value. If the ink viscosity is higher than the standard viscosity (Δη>0), the flight speed of the ink droplets may decrease, resulting in the landing point being behind. At this time, β is positive, which is used to increase the inkjet grating adjustment value.

[0105] The first corrected grating adjustment value is ΔSn1 = ΔSn + k1×ΔSn.

[0106] After obtaining the first corrected grating adjustment value, in order to ensure the accuracy of the ink droplet landing point, test printing can be performed again according to the first corrected grating adjustment value to monitor the flight trajectory and landing position of the ink droplets, and calculate the second distance deviation. If the second distance deviation is less than or equal to the first threshold but greater than the second threshold, it indicates that the deviation of the ink droplet landing point has decreased, but still has not reached the ideal state. At this time, according to the first difference between the nozzle temperature and the standard temperature and the second difference between the ink viscosity and the standard viscosity, the heating coefficient is calculated. The calculation relationship among the first difference, the second difference, and the heating coefficient can be obtained through experiments. The heating coefficient is used to adjust the heating power of the nozzle so that the nozzle temperature gradually approaches the preset standard temperature, and at the same time, the ink viscosity also gradually approaches the preset standard viscosity. Through heating adjustment, the third difference between the nozzle temperature and the standard temperature will be controlled within the preset temperature difference range, and the fourth difference between the ink viscosity and the standard viscosity will also be controlled within the preset viscosity difference range. After the nozzle temperature and the ink viscosity are effectively adjusted, the second correction coefficient will be calculated according to the third difference and the fourth difference. This correction coefficient is used to further adjust the inkjet grating adjustment value to compensate for the deviation of the ink droplet landing point caused by temperature and viscosity changes. Through the second correction coefficient, the second corrected grating adjustment value is generated. The specific calculation method is similar to the above first corrected grating adjustment value and will not be elaborated here. In other embodiments, the calculation method can also be adjusted according to the actual application situation. The second corrected grating adjustment value is used as the new inkjet grating adjustment value. Then, according to the new inkjet grating adjustment value, the printing carriage is controlled to perform inkjet printing to ensure the accuracy of the ink droplet landing point and the stability of the printing quality. Moreover, by heating and adjusting the nozzle temperature and the ink viscosity, the influence of environmental temperature, humidity and other factors on the printing quality can be effectively coped with, and the adaptability and stability of the printing system can be further improved.

[0107] In addition to the influence of the nozzle temperature and the ink viscosity, in other embodiments, the influence of air resistance on the flight trajectory and landing position of the ink droplets can be further considered, and a new first correction coefficient or second correction coefficient can be obtained by combining parameters such as the nozzle temperature, the ink viscosity, and the air resistance, and then a new second corrected grating adjustment value or second corrected grating adjustment value can be obtained. According to the second corrected grating adjustment value, the printing carriage is driven to perform inkjet printing, so that the ink droplet landing point is more accurate and better printing quality is achieved.

[0108] In summary, the variable-speed motion inkjet printing method for a printing carriage provided by the embodiments of the present invention obtains the motion speed corresponding to the starting printing position during the variable-speed motion of the printing carriage along the X-axis direction, denoted as the first speed, where the X-axis direction is the printing direction; obtains the flight distance of the ink droplets when the printing carriage prints at a constant speed along the X-axis direction, denoted as the second distance; obtains the flight distance of the ink droplets along the X-axis direction when the printing carriage ejects ink droplets from the starting printing position according to the first speed and the second distance, denoted as the first distance; obtains the inkjet grating adjustment value according to the first distance and the second distance; and drives the printing carriage to perform inkjet printing during the variable-speed motion along the X-axis direction according to the inkjet grating adjustment value. The method adjusts the ejection timing of the ink droplets during the variable-speed motion printing process through the inkjet grating adjustment value, so that the interval between the ink droplet landing points or pixel points during variable-speed printing is uniform and the same as that during constant-speed printing, thereby ensuring the image printing effect. Since printing is performed during the variable-speed motion stage, the printing efficiency in each PASS printing process can be significantly improved, the printing production capacity is increased, and at the same time, the utilization rate of the printing medium can be improved, which is beneficial to reducing the material cost.

[0109] Embodiment 2

[0110] Please refer to Figure 6 , the embodiments of the present invention provide a variable-speed motion inkjet printing device 200 for a printing carriage. The device 200 includes:

[0111] A first speed acquisition module 201, configured to acquire the motion speed corresponding to the starting printing position during the variable-speed motion of the printing carriage along the X-axis direction, denoted as the first speed, where the X-axis direction is the printing direction;

[0112] A second distance acquisition module 202, configured to acquire the flight distance of the ink droplets when the printing carriage prints at a constant speed along the X-axis direction, denoted as the second distance;

[0113] A first distance acquisition module 203, configured to acquire the flight distance of the ink droplets along the X-axis direction when the printing carriage ejects ink droplets from the starting printing position according to the first speed and the second distance, denoted as the first distance;

[0114] A grating adjustment value acquisition module 204, configured to acquire the inkjet grating adjustment value according to the first distance and the second distance;

[0115] A printing module 205, configured to drive the printing carriage to perform inkjet printing during the variable-speed motion along the X-axis direction according to the inkjet grating adjustment value.

[0116] In summary, the variable-speed motion inkjet printing device for a printing carriage provided by the embodiment of the present invention obtains the motion speed corresponding to the starting printing position during the variable-speed motion of the printing carriage in the X-axis direction, denoted as the first speed, where the X-axis direction is the printing direction; obtains the flight distance of ink droplets when the printing carriage performs uniform printing in the X-axis direction, denoted as the second distance; obtains the flight distance of the ink droplets in the X-axis direction when the printing carriage ejects ink droplets from the starting printing position according to the first speed and the second distance, denoted as the first distance; obtains an inkjet grating adjustment value according to the first distance and the second distance; and drives the printing carriage to perform inkjet printing during the variable-speed motion in the X-axis direction according to the inkjet grating adjustment value. The method adjusts the ejection timing of ink droplets during the variable-speed motion printing process through the inkjet grating adjustment value, so that the interval between the ink drop landing points or pixel points during variable-speed printing is uniform and the same as that during uniform printing, thereby ensuring the image printing effect. Since printing is performed during the variable-speed motion stage, the printing efficiency in each PASS printing process can be significantly improved, and the printing productivity is increased.

[0117] Embodiment III

[0118] In addition, the variable-speed motion inkjet printing method for a printing carriage according to the embodiment of the present invention can be implemented by a variable-speed motion inkjet printing device for a printing carriage. Figure 7 Fig. shows a schematic hardware structure diagram of a variable-speed motion inkjet printing device for a printing carriage provided by an embodiment of the present invention.

[0119] The variable-speed motion inkjet printing device for a printing carriage may include a processor 301 and a memory 302 storing computer program instructions.

[0120] Specifically, the above-mentioned processor 301 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention.

[0121] The memory 302 may include a mass memory for data or instructions. By way of example and not limitation, the memory 302 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive, or a combination of two or more of these. In suitable cases, the memory 302 may include removable or non-removable (or fixed) media. In suitable cases, the memory 302 may be internal or external to the data processing device. In a particular embodiment, the memory 302 is a non-volatile solid-state memory. In a particular embodiment, the memory 302 includes a read-only memory (ROM). In suitable cases, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), an electrically rewritable ROM (EAROM), or a flash memory, or a combination of two or more of these.

[0122] The processor 301 reads and executes the computer program instructions stored in the memory 302 to implement any one of the printing carriage variable-speed motion inkjet printing methods in the above embodiments.

[0123] In one example, the printing carriage variable-speed motion inkjet printing device may further include a communication interface 303 and a bus 310. Among them, as Figure 7 shown, the processor 301, the memory 302, and the communication interface 303 are connected through the bus 310 and complete communication with each other.

[0124] The communication interface 303 is mainly used to implement communication between various modules, devices, units, and / or devices in the embodiments of the present invention.

[0125] The bus 310 includes hardware, software, or both, and couples the components of the printing carriage variable-speed motion inkjet printing device to each other. By way of example and not limitation, the bus 310 may include an accelerated graphics port (AGP) or other graphics bus, an enhanced industry standard architecture (EISA) bus, a front-side bus (FSB), a hyperTransport (HT) interconnect, an industry standard architecture (ISA) bus, an InfiniBand interconnect, a low-pin count (LPC) bus, a memory bus, a microChannel architecture (MCA) bus, a peripheral component interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a serial advanced technology attachment (SATA) bus, a video electronics standards association local (VLB) bus, or other suitable buses, or a combination of two or more of these. In suitable cases, the bus 310 may include one or more buses. Although the embodiments of the present invention describe and illustrate specific buses, the present invention contemplates any suitable bus or interconnect.

[0126] Embodiment 4

[0127] In addition, in combination with the inkjet printing method with variable-speed movement of the printing carriage in the above embodiments, an embodiment of the present invention can be implemented by providing a computer-readable storage medium. Computer program instructions are stored on the computer-readable storage medium; when the computer program instructions are executed by the processor 301, any one of the inkjet printing methods with variable-speed movement of the printing carriage in the above embodiments is implemented.

[0128] In summary, the inkjet printing method, device, equipment and storage medium provided by the embodiments of the present invention obtain the movement speed corresponding to the starting printing position during the variable-speed movement of the printing carriage along the X-axis direction, denoted as the first speed, where the X-axis direction is the printing direction; obtain the flight distance of the ink droplets when the printing carriage prints at a constant speed along the X-axis direction, denoted as the second distance; obtain the flight distance of the ink droplets along the X-axis direction when the printing carriage ejects ink droplets from the starting printing position according to the first speed and the second distance, denoted as the first distance; obtain the inkjet grating adjustment value according to the first distance and the second distance; and drive the printing carriage to perform inkjet printing during the variable-speed movement along the X-axis direction according to the inkjet grating adjustment value. The method adjusts the ejection timing of the ink droplets during the variable-speed movement printing process through the inkjet grating adjustment value, so that the interval between the ink droplet landing points or pixel points during variable-speed printing is uniform and the same as that during constant-speed printing, thereby ensuring the image printing effect. Since printing is performed during the variable-speed movement stage, the printing efficiency in each PASS printing process can be significantly improved, and the printing productivity is increased.

[0129] It should be clear that the present invention is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, the detailed description of known methods is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present invention.

[0130] The functional blocks shown in the above-described structural block diagrams can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (ASIC), appropriate firmware, a plug-in, a functional card, and so on. When implemented in software, the elements of the present invention are programs or code segments for performing the required tasks. The program or code segment can be stored in a machine-readable medium or transmitted via a data signal carried in a carrier wave on a transmission medium or a communication link. A "machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROMs, flash memories, erasable ROMs (EROMs), floppy disks, CD-ROMs, optical discs, hard disks, fiber optic media, radio frequency (RF) links, and so on. The code segment can be downloaded via a computer network such as the Internet, an intranet, and so on.

[0131] It should also be noted that the exemplary embodiments mentioned in the present invention describe some methods or systems based on a series of steps or devices. However, the present invention is not limited to the order of the above steps, that is, the steps can be executed in the order mentioned in the embodiments, or different from the order in the embodiments, or several steps can be executed simultaneously.

[0132] As described above, the above is only the specific implementation manner of the present invention. Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the systems, modules, and units described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein. It should be understood that the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present invention.

Claims

1. A method for inkjet printing with a printing carriage having variable speed motion, characterized in that: The method comprises: Obtain the movement speed corresponding to the starting printing position during the variable speed movement of the printing carriage along the X-axis direction, recorded as the first speed, where the X-axis direction is the printing direction; Obtaining the flying distance of ink droplets when the printing carriage prints at a uniform speed along the X-axis direction, recorded as a second distance; According to the first speed and the second distance, the flying distance of the ink droplets along the X-axis direction when the printing carriage ejects the ink droplets from the starting printing position is obtained, and recorded as the first distance; Acquiring the inkjet grating adjustment value according to the first distance and the second distance includes: acquiring a reference ink droplet landing point deviation value according to the first distance and the second distance; acquiring the number of variable speed printing pixels according to the printing width and printing accuracy in the X-axis direction in the variable speed movement stage; acquiring the inkjet grating adjustment value corresponding to each variable speed printing pixel according to the reference ink droplet landing point deviation value and the number of variable speed printing pixels; According to the inkjet grating adjustment value, the printing carriage is driven to perform inkjet printing during the variable speed movement along the X-axis direction.

2. The inkjet printing method for printing carriage with variable speed motion according to claim 1, characterized in that: The method of obtaining the movement speed corresponding to the starting printing position during the variable speed movement of the printing carriage along the X-axis direction, recorded as the first speed, includes: Obtain the movement speed of the printing carriage during inkjet printing at a uniform speed along the X-axis direction, recorded as the second speed; Obtaining a corresponding movement distance when the printing carriage accelerates from rest to the first speed, recorded as the accelerated movement distance; Acquire the acceleration of the printing carriage when it performs variable speed motion according to the accelerated motion distance and the second speed; Determine the starting printing position of the printing carriage in the phase of variable speed movement along the X-axis; A first speed of the printing carriage corresponding to the starting printing position is acquired according to the acceleration.

3. The inkjet printing method for printing carriage with variable speed motion according to claim 1, characterized in that: The step of obtaining the flying distance of ink droplets when the printing carriage is printing at a uniform speed along the X-axis direction, recorded as the second distance, includes: Obtaining a bidirectional calibration value when the printing carriage performs bidirectional calibration printing along the X-axis direction; The second distance is acquired according to the bidirectional calibration value.

4. The inkjet printing method for printing carriage with variable speed motion according to claim 2, characterized in that: The step of obtaining the flying distance of the ink droplets along the X-axis direction when the printing carriage ejects the ink droplets from the starting printing position according to the first speed and the second distance, recorded as the first distance, includes: Obtaining the vertical movement distance and vertical speed corresponding to the ink droplets ejected when the printing carriage moves at a uniform speed in the X-axis direction and falling along the Z-axis direction; wherein the Z-axis direction is perpendicular to the X-axis direction and the Y-axis direction, and the Y-axis direction is the direction in which the printing carriage steps relative to the printing medium; Obtaining a second ratio of the vertical movement distance to the vertical speed according to a first ratio of the second distance to the second speed; The flying distance of the ink droplet along the X-axis direction when the ink droplet is ejected from the starting printing position is obtained according to the first speed and the second ratio, which is the first distance.

5. The inkjet printing method for printing carriage with variable speed motion according to claim 1, characterized in that: The obtaining of a reference ink droplet landing point deviation value according to the first distance and the second distance comprises: The reference ink drop landing point deviation value is obtained according to the following formula: ； in is the reference ink drop landing point deviation value, L is the second distance, and m0 is the first distance.

6. The inkjet printing method for printing carriage with variable speed motion according to claim 5, characterized in that: The step of obtaining the inkjet raster adjustment value corresponding to each variable speed printing pixel point according to the reference ink drop landing point deviation value and the variable speed printing pixel point quantity comprises: When the printing carriage is in accelerated motion, ; When the printing carriage is in deceleration motion, ; in, The inkjet raster adjustment value for the nth variable speed printing pixel. is the reference ink drop landing point deviation value, and h is the number of variable speed printing pixels.

7. The inkjet printing method for printing carriage with variable speed motion according to any one of claims 1 to 6, characterized in that: Before the printing carriage is driven to perform inkjet printing in the process of variable speed movement along the X-axis direction according to the inkjet grating adjustment value, the method further comprises: Controlling the printing carriage to spray ink droplets at corresponding positions according to the inkjet grating adjustment value; Monitoring the flight trajectory and landing position of the ink drop, and calculating a first distance deviation between an actual landing point of the ink drop and an expected landing point; If the first distance deviation is greater than a first threshold, the nozzle temperature and ink viscosity in the printing carriage are obtained; Obtaining a first correction coefficient according to a first difference between the nozzle temperature and a preset standard temperature, and a second difference between the ink viscosity and a preset standard viscosity; Adjusting the inkjet grating adjustment value according to the first distance deviation and the first correction coefficient to obtain a first corrected grating adjustment value; Controlling the printing carriage to eject ink droplets at corresponding positions according to the first corrected grating adjustment value; Monitoring the flight trajectory and landing position of the ink drop, and calculating a second distance deviation between an actual landing point of the ink drop and an expected landing point; If the second distance deviation is less than or equal to the first threshold but greater than the second threshold, a heating coefficient is obtained according to the first difference and the second difference, and the nozzle is heated according to the heating coefficient so that a third difference between the nozzle temperature and the preset standard temperature is within a preset temperature difference range and a fourth difference between the ink viscosity and the preset standard viscosity is within a preset viscosity difference range; Obtaining a second correction coefficient according to the third difference and the fourth difference; The inkjet grating adjustment value is adjusted according to the second distance deviation and the second correction coefficient to obtain a second corrected grating adjustment value; A new inkjet raster adjustment value is obtained according to the second corrected raster adjustment value.

8. A variable speed inkjet printing device for a printing carriage, characterized in that: The device comprises: A first speed acquisition module is used to acquire the movement speed corresponding to the starting printing position during the variable speed movement of the printing carriage along the X-axis direction, which is recorded as the first speed, wherein the X-axis direction is the printing direction; A second distance acquisition module is used to acquire the flying distance of the ink droplets when the printing carriage prints at a uniform speed along the X-axis direction, which is recorded as the second distance; A first distance acquisition module, used for acquiring, according to the first speed and the second distance, a flying distance of ink droplets along the X-axis direction when the printing carriage ejects ink droplets from the starting printing position, recorded as a first distance; The grating adjustment value acquisition module is used to acquire the inkjet grating adjustment value according to the first distance and the second distance, including: acquiring a reference ink droplet landing point deviation value according to the first distance and the second distance; acquiring the number of variable speed printing pixels according to the printing width and printing accuracy in the X-axis direction in the variable speed movement stage; acquiring the inkjet grating adjustment value corresponding to each variable speed printing pixel according to the reference ink droplet landing point deviation value and the number of variable speed printing pixels; The printing module is used to drive the printing carriage to perform inkjet printing during the variable speed movement along the X-axis direction according to the inkjet grating adjustment value.

9. An inkjet printing device with a printing carriage having variable speed motion, characterized in that: include: At least one processor, at least one memory and computer program instructions stored in the memory, when the computer program instructions are executed by the processor, implement the method according to any one of claims 1 to 7.

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