Method and equipment for improving ink jet effect under low-temperature condition and storage medium

Abstract

The invention discloses a method and device for improving the ink jet effect under the low-temperature condition and a storage medium, and the method comprises the following steps: S1, after a printer is started, opening an ink circulation system, and enabling ink to be in a flowing state; s2, giving an empty spraying signal to the nozzle, simulating the nozzle to print but not discharge ink, and enabling the nozzle to achieve a preheating effect; s3, before printing is started, a flash spraying signal is given to the nozzle, and the action of full-nozzle vigorous ink output is instantly carried out; s4, printing operation is started after flash spraying is completed; the problem that the printing effect of the ink-jet printer is poor when the ink-jet printer is just started at a low temperature can be effectively solved, the preheating degree of the spray head can be accurately controlled by obtaining and comparing the spray head temperature and the environment temperature, it is ensured that the optimal printing temperature is achieved, and the ink-jet stability and quality can be improved through temperature difference comparison and corresponding adjustment.

Description

Technical Field

[0001] The invention relates to the field of printers, and in particular to a method, a device and a storage medium for improving inkjet effects under low temperature conditions. Background Art

[0002] In the process of inkjet printing, the physical and chemical parameters of ink, such as viscosity, fluidity, surface tension, etc., play a vital role in the printout effect. However, environmental factors, especially high or low ambient temperature, high or low humidity, will cause some changes in the physical and chemical parameters of the ink to a certain extent, thus significantly affecting the printout effect. Among them, for solvent, weak solvent, UV and other inks, this effect is more obvious.

[0003] For example, in low temperature environments such as winter, when the inkjet printer starts working, the temperature of the nozzle is still low. Printing at this time often causes problems such as weak printing. After the nozzle has been working for a period of time, the temperature of the nozzle gradually rises, and the physical and chemical parameters of the ink are improved under the action of temperature, and the printing effect will improve.

[0004] To solve the problem of poor printing effect at low temperature, most manufacturers currently adopt the measure of equipping the print head with a heating device. Although the heating device can effectively increase the temperature of the print head and improve the ink state during the operation of the print head, thereby improving the printing effect, there is an obvious defect, that is, when the machine is in standby mode, if the heating device is always turned on, it will cause a waste of energy resources and increase the cost of use, which is disadvantageous for users who use inkjet printers for a long time.

[0005] Therefore, it is necessary to develop a solution that can effectively solve the problem of poor printing effect of inkjet printers when they are just turned on at low temperatures, and avoid wasting resources due to the continuous opening of the heating device when the machine is in standby mode. Summary of the invention

[0006] In order to solve the above-mentioned technical problems, the present invention provides a method, a device and a storage medium for improving inkjet effect under low temperature conditions.

[0007] The technical solution of the present invention is achieved in this way:

[0008] A method for improving inkjet effect under low temperature conditions comprises the following steps:

[0009] S1, after the printer is turned on, the ink circulation system is turned on to keep the ink flowing;

[0010] S2, give the nozzle an empty spray signal, simulate the nozzle printing but the nozzle does not produce ink, so that the nozzle can achieve the preheating effect;

[0011] S3, before starting printing, gives the print head a flash signal, and all print heads start to spray ink vigorously instantly;

[0012] S4, after the flash printing is completed, the printing job starts.

[0013] Preferably, the step S2 further includes the following sub-steps:

[0014] S21, obtaining the nozzle temperature of the nozzle temperature sensor and the printing environment temperature;

[0015] S22, setting the best print head temperature and ambient temperature matching the print head model;

[0016] S23, comparing the set optimal print head temperature and the ambient temperature with the print head temperature to obtain a difference a after comparison;

[0017] S24, after the nozzle is preheated by air spraying, the current nozzle temperature is obtained, and the current nozzle temperature is compared with the optimal printing nozzle temperature to obtain the difference a1 after comparison. When a1 is greater than 5, step S23 is repeated until a1 is less than 5.

[0018] Preferably, the nozzle empty spray signal of S2 is a waveform signal, the frequency is set to 200-300Hz, the positive voltage amplitude is set to 30-50V, and the negative voltage amplitude is set to negative 30-50V.

[0019] Preferably, the step S3 further includes the following sub-steps:

[0020] S31, after the print head flashes, the flash ink spraying condition of the printing medium is detected by the built-in camera of the printer through image recognition. When the flash ink spraying is confirmed, the print head temperature and the current printing environment temperature are obtained. When the flash ink spraying fails, the flash ink spraying is continued until the detection is successful.

[0021] S32, setting the best print head temperature and ambient temperature matching the print head model;

[0022] S33, comparing the set optimal print head temperature and the ambient temperature with the print head temperature to obtain a difference value b after comparison;

[0023] S34, obtaining the current nozzle temperature, comparing the current nozzle temperature with the optimal printing nozzle temperature, obtaining the difference b1 after comparison, and when b1 is greater than 2, starting to configure a heating device for the nozzle, until b1 is less than 2, stopping configuring the heating device for the nozzle.

[0024] Preferably, in step S2, a table is created to record the ambient temperature and nozzle temperature before and after the empty spraying, which is used as the nozzle empty spraying temperature rise amplitude at the ambient temperature, and the empty spraying number i is set for the nozzle heating according to the temperature rise amplitude; and the nozzle heating voltage increase is recorded, and the voltage increase threshold is set, and an abnormal alarm is issued when the nozzle heating voltage increase approaches the threshold.

[0025] Preferably, the historical temperature rise amplitude q of the table is obtained through historical records, the current temperature rise amplitude is k, and the normal amplitude is 5≤qn≤12. When the normal amplitude is exceeded, the nozzle sends a temperature abnormality signal and starts the nozzle configuration heating device until the difference b1 between the front nozzle temperature and the optimal printing nozzle temperature is less than 2, and then the nozzle configuration heating device is stopped.

[0026] A printing device includes 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 for improving inkjet effect under low temperature conditions is implemented.

[0027] A storage medium stores computer program instructions, wherein the method for improving inkjet effect under low temperature conditions is implemented when the computer program instructions are executed by a processor.

[0028] The present invention can effectively solve the problem of poor printing effect when the inkjet printer is just turned on at a low temperature. By obtaining and comparing the nozzle and ambient temperature, the nozzle preheating degree can be accurately controlled to ensure that a temperature close to the optimal printing temperature is reached. For example, the temperature difference comparison and corresponding adjustment in steps S2 and S3 can improve the inkjet stability and quality. A table can be established to record temperature and other data. The number of empty sprays and the voltage increase can be set according to the temperature rise amplitude. The abnormality can be detected in time and measures can be taken by comparing the historical and current temperature rise amplitudes, thereby effectively maintaining the normal operation of the nozzle. As a whole, the inkjet effect can be better improved in a low temperature environment and the stable operation of the equipment can be guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of a method for improving inkjet effect under low temperature conditions of the present invention. DETAILED DESCRIPTION

[0030] In order to further explain the technical means and effects taken by the present invention to achieve the predetermined invention purpose, exemplary embodiments will be described in detail here, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are only examples of methods and systems consistent with some aspects of the present application as detailed in the attached claims.

[0031] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0032] A method for improving inkjet effect under low temperature conditions comprises the following steps:

[0033] S1, after the printer is turned on, the ink circulation system is turned on to keep the ink flowing;

[0034] S2, giving the nozzle an empty spray signal, simulating the nozzle printing but the nozzle does not produce ink, so that the nozzle can achieve the preheating effect; the control system sends a specific waveform empty spray signal to the nozzle, and the nozzle simulates the printing action according to the signal. Although no ink is produced, the relevant components inside the nozzle, such as piezoelectric ceramic elements, will move, thereby generating heat to achieve preheating;

[0035] The step S2 further includes the following sub-steps:

[0036] S21, obtaining the nozzle temperature and the printing environment temperature of the nozzle temperature sensor; accurately obtaining the current temperature value of the nozzle through the nozzle temperature sensor, and at the same time obtaining the printing environment temperature of the printer, in preparation for subsequent precise control;

[0037] S22, setting the best print head temperature and ambient temperature matching the print head model; for a specific print head model, based on past experimental tests, print head performance parameters, and actual printing experience, setting the print head temperature and the ambient temperature value that can achieve the best printing effect for the print head;

[0038] S23, comparing the set optimal print head temperature and the ambient temperature with the print head temperature, and obtaining a difference a after comparison; comparing the set optimal print head temperature and the ambient temperature with the actually obtained print head temperature, respectively, and calculating a difference a between the two in temperature values, so as to measure the degree of deviation between the current temperature and the ideal temperature;

[0039] The calculation method of the difference a is: set the difference between the optimal print head temperature and the actual print head temperature to be l, the ambient temperature to be o, and the environmental impact coefficient to be c, then a=lo*c;

[0040] If the nozzle is directly printed in a low temperature environment, the ink jetting effect will be very poor, such as uneven ink droplet size and unstable jetting speed. Preheating the nozzle by air jetting can increase the nozzle temperature, improve the physical and chemical properties of the ink in the nozzle, reduce the ink viscosity, and enable the ink to spray ink droplets more accurately according to the control system instructions, thereby improving the printing quality. Accurate monitoring and comparative adjustment of the temperature can ensure that the nozzle is preheated to an appropriate degree to avoid over-preheating or under-preheating.

[0041] S24, after the nozzle is preheated by air spraying, the current nozzle temperature is obtained, and the current nozzle temperature is compared with the optimal printing nozzle temperature to obtain the difference a1 after comparison. When a1 is greater than 5, step S23 is repeated until a1 is less than 5.

[0042] S3, before starting printing, a flash spray signal is given to the nozzle, and the whole nozzle ejects ink with great force instantly; the printer control system generates a flash spray signal and sends it to the nozzle, and the nozzle instantly ejects ink with great force after receiving the signal, ejecting the ink in the nozzle with great force;

[0043] The step S3 further includes the following sub-steps:

[0044] S31, after the nozzle flashes, the built-in camera of the printer uses image recognition to detect the flash ink spraying of the printing medium. When the flash ink spraying is confirmed, the nozzle temperature and the current printing environment temperature are obtained. When the flash ink spraying fails, the flash ink spraying continues until the detection is successful. The printer control system has built-in advanced image recognition algorithms. When the camera captures the image on the printing medium, the algorithm will process and analyze the image. First, the algorithm will grayscale the image and convert the color image into a grayscale image to simplify the subsequent analysis process and reduce the amount of calculation. Then, through the edge detection algorithm, such as the Canny edge detection algorithm, the edge contour of the ink trace in the image is identified to accurately define the distribution range of the ink; then, the area filling algorithm is used to determine the area covered by the ink and compare it with the preset standard area range. At the same time, the concentration distribution of the ink traces will be analyzed, and the degree of ink density at different positions will be judged by detecting the change in the grayscale value of the pixel point.

[0045] S32, setting the best print head temperature and ambient temperature matching the print head model;

[0046] S33, comparing the set optimal print head temperature and the ambient temperature with the print head temperature to obtain a difference value b after comparison;

[0047] The calculation method of the difference b is the same as that of the difference a;

[0048] S34, obtaining the current nozzle temperature, comparing the current nozzle temperature with the optimal printing nozzle temperature, obtaining the difference b1 after comparison, and when b1 is greater than 2, starting to configure a heating device for the nozzle, until b1 is less than 2, stopping configuring the heating device for the nozzle.

[0049] S4, after the flash printing is completed, the printing job starts.

[0050] Preferably, the nozzle empty spray signal of S2 is a waveform signal, the frequency is set to 200-300Hz, the positive voltage amplitude is set to 30-50V, and the negative voltage amplitude is set to negative 30-50V.

[0051] Preferably, in step S2, a table is created to record the ambient temperature and nozzle temperature before and after the empty spraying, which is used as the nozzle empty spraying temperature rise amplitude at the ambient temperature, and the empty spraying number i is set for the nozzle heating according to the temperature rise amplitude; and the nozzle heating voltage increase is recorded, and the voltage increase threshold is set, and an abnormal alarm is issued when the nozzle heating voltage increase approaches the threshold.

[0052] Preferably, the historical temperature rise amplitude q of the table is obtained through historical records, the current temperature rise amplitude is k, and the normal amplitude is 5≤qn≤12. When the normal amplitude is exceeded, the nozzle sends a temperature abnormality signal and starts the nozzle configuration heating device until the difference b1 between the front nozzle temperature and the optimal printing nozzle temperature is less than 2, and then the nozzle configuration heating device is stopped.

[0053] A printing device includes 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 for improving inkjet effect under low temperature conditions is implemented.

[0054] A storage medium stores computer program instructions, wherein the method for improving inkjet effect under low temperature conditions is implemented when the computer program instructions are executed by a processor.

[0055] Example 2

[0056] This embodiment provides a method for improving inkjet effect under low temperature conditions, comprising the following steps:

[0057] S1, when the system starts, obtains the initial current nozzle temperature, T_current, and the ambient temperature, T_environment,, calculates the current nozzle temperature deviation, ΔT, and the current nozzle temperature change rate, dT / dt,, and inputs these values ​​into the fuzzy logic control system.

[0058] S2, fuzzify the input variables according to their respective membership functions to obtain the membership degree of the input variables to each fuzzy set.

[0059] S3, according to the fuzzy reasoning rules, combined with the membership of the input variables, fuzzy reasoning is performed to obtain the fuzzy sets and corresponding memberships of the output variables "nozzle heating power adjustment coefficient, K_heat," and "nozzle cooling power adjustment coefficient, K_cool," respectively.

[0060] S4, using defuzzification methods such as the centroid method, the fuzzy set of the output variable and the corresponding membership degree obtained by fuzzy reasoning are converted into specific values, that is, the specific nozzle heating power adjustment coefficient, K_heat, and the nozzle cooling power adjustment coefficient, K_cool, are obtained.

[0061] S5, the controller adjusts the heating power of the nozzle heating device and the cooling power of the nozzle cooling system according to the obtained nozzle heating power adjustment coefficient, K_heat, and nozzle cooling power adjustment coefficient, K_cool, to control the nozzle temperature.

[0062] S6, continuously monitors the current nozzle temperature, T_current,, the ambient temperature, T_environment,, the current nozzle temperature deviation, ΔT, and the current nozzle temperature change rate, dT / dt,, and continuously cycles according to the above process to adjust the nozzle heating power and cooling power in real time to keep the nozzle temperature within a suitable range to ensure the normal operation of the nozzle and the printing quality.

[0063] Preferably, the step S3 further includes the following sub-steps:

[0064] S31, obtaining the difference between the current temperature of the nozzle and the preset optimal temperature of the nozzle;

[0065] S32, set the deviation threshold and extreme deviation threshold of the difference, the deviation threshold is 10, the extreme deviation threshold is 20, when the difference is greater than the deviation threshold 10 and less than 20, the required heating power is level 3, when the difference is less than 10 and greater than 7, the required heating power is level 2, when the difference is less than 7, the required heating power is level 1.

[0066] S33, calculate the change of nozzle temperature per unit time, set it as the current nozzle temperature change rate, calculate the time required for preheating, and when the time required for preheating is not greater than the set time, the heating power remains unchanged. When the time required for preheating is greater than the set time, the heating power increases by 1 level.

[0067] Example 3

[0068] This embodiment provides a method for improving inkjet effect under low temperature conditions, comprising the following steps:

[0069] S1, through historical data, establish a voltage and temperature relationship model to formulate corresponding voltage adjustment strategies;

[0070] S2, according to the best printing performance requirements of the printhead, determine the target temperature range of the printhead under different printing tasks, such as different types of inks, different printing resolution requirements, etc. For example, for a high-precision printing task using a certain high-viscosity ink, the target temperature of the printhead may be determined to be 50℃-60℃; while for a normal text printing task, the target temperature may be set at 30℃-40℃;

[0071] S3, obtaining the temperature information of the nozzle in real time through the sensor, and converting the output signal of the sensor into a digital signal through a suitable signal acquisition circuit so that it can be processed by the control system of the printer;

[0072] S4, start printing job;

[0073] Preferably, in step S2, it is detected that the current nozzle temperature is lower than the lower limit of the target temperature range:

[0074] Sa21, when the current nozzle temperature is detected by the sensor to be lower than the lower limit of the target temperature range, the voltage value corresponding to the lower limit of the target temperature range is found according to the voltage and temperature relationship model established previously;

[0075] Sa22, set the voltage adjustment step size, such as increasing by 2V each time. Starting from the actual voltage value applied to the current nozzle, gradually increase the voltage according to the set step size. Assuming that the current nozzle voltage is 20V, then after the first adjustment, the voltage becomes 20+2=22V, and after the second adjustment, it becomes 22+2=24V, and so on, gradually approaching the target voltage value of 30V;

[0076] Sa23, after each voltage increase, immediately use the temperature sensor to monitor the change of the nozzle temperature in real time. Since the change of the nozzle temperature may not be completed instantly, it is necessary to wait for a while, such as monitoring once every 5 seconds and continuously monitoring for 30 seconds, to observe whether the nozzle temperature has an upward trend and the extent of the increase; if it is found that the nozzle temperature has not increased significantly or the increase is very small in several consecutive monitorings, it may be necessary to appropriately extend the waiting time or further check whether there is a fault in the nozzle, such as internal blockage of the nozzle, circuit connection problems, etc., to ensure that the temperature can respond normally to the voltage adjustment;

[0077] Sa24, continue to adjust the voltage and monitor the temperature until the nozzle temperature reaches or exceeds the lower limit of the target temperature range. Once the nozzle temperature reaches the target temperature range, such as 45°C, the voltage adjustment operation is stopped. At this time, the nozzle temperature has met the lower limit of the printing requirements and can be prepared for subsequent printing preparations.

[0078] Preferably, in step S2, when the current nozzle temperature is detected to be higher than the upper limit of the target temperature range, the voltage value corresponding to the upper limit of the target temperature range is also found according to the voltage-temperature relationship model. For example, the upper limit of the target temperature range is 55°C, and the nozzle voltage value corresponding to 55°C should be 20V according to the model. Assume that.

[0079] Preferably, in step S2, it is detected that the current nozzle temperature is lower than the upper limit of the target temperature range:

[0080] Sb21, when the current nozzle temperature is detected to be higher than the upper limit of the target temperature range, the voltage value corresponding to the upper limit of the target temperature range is also found based on the voltage-temperature relationship model; for example, if the upper limit of the target temperature range is 55°C, the nozzle voltage value corresponding to 55°C should be 20V according to the model;

[0081] Sb22, set the voltage adjustment step, for example, reduce 2V each time; starting from the actual voltage value applied to the current nozzle, gradually reduce the voltage according to the set step; if the current nozzle voltage is 30V, then after the first adjustment, the voltage becomes 30-2=28V, and after the second adjustment, it becomes 28-2=26V, and so on, gradually adjusting towards the target voltage value of 20V

[0082] Sb23, after each voltage reduction, quickly use the temperature sensor to monitor the change of the nozzle temperature in real time; it is also necessary to wait for a period of time to observe the temperature drop trend and amplitude, such as monitoring once every 5 seconds and continuously monitoring for 30 seconds. If it is found that the nozzle temperature drops too slowly or does not drop significantly, it may be necessary to check whether there is a heat dissipation problem in the nozzle, such as whether the heat dissipation channel around the nozzle is blocked, whether the heat dissipation fan is working normally, etc., to ensure that the temperature can respond normally to the voltage adjustment;

[0083] Sb24, continue to adjust the voltage and monitor the temperature until the nozzle temperature drops to within the target temperature range; when the nozzle temperature falls into the target temperature range, stop the voltage adjustment operation. At this time, the nozzle temperature meets the printing requirements and the subsequent printing preparation work can continue.

[0084] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for improving inkjet effect under low temperature conditions, characterized in that: The steps include: S1, after the printer is turned on, the ink circulation system is turned on to keep the ink flowing; S2, give the nozzle an empty spray signal, simulate the nozzle printing but the nozzle does not produce ink, so that the nozzle can achieve the preheating effect; S3, before starting printing, gives the print head a flash signal, and all print heads start to spray ink vigorously instantly; S4, after the flash printing is completed, the printing job starts.

2. The method for improving inkjet effect under low temperature conditions according to claim 1, characterized in that: The step S2 further includes the following sub-steps: S21, obtaining the nozzle temperature of the nozzle temperature sensor and the printing environment temperature; S22, setting the best print head temperature and ambient temperature matching the print head model; S23, comparing the set optimal print head temperature and the ambient temperature with the print head temperature to obtain a difference a after comparison; S24, after the nozzle is preheated by air spraying, the current nozzle temperature is obtained, and the current nozzle temperature is compared with the optimal printing nozzle temperature to obtain the difference a1 after comparison. When a1 is greater than 5, step S23 is repeated until a1 is less than 5.

3. The method for improving inkjet effect under low temperature conditions according to claim 1, characterized in that: The nozzle empty spray signal of S2 is a waveform signal, the frequency is set to 200-300Hz, the positive voltage amplitude is set to 30-50V, and the negative voltage amplitude is set to negative 30-50V.

4. The method for improving inkjet effect under low temperature conditions according to claim 1, characterized in that: The step S3 further includes the following sub-steps: S31, after the print head flashes, the flash ink spraying condition of the printing medium is detected by the built-in camera of the printer through image recognition. When the flash ink spraying is confirmed, the print head temperature and the current printing environment temperature are obtained. When the flash ink spraying fails, the flash ink spraying is continued until the detection is successful. S32, setting the best print head temperature and ambient temperature matching the print head model; S33, comparing the set optimal print head temperature and the ambient temperature with the print head temperature to obtain a difference value b after comparison; S34, obtaining the current nozzle temperature, comparing the current nozzle temperature with the optimal printing nozzle temperature, obtaining the difference b1 after comparison, and when b1 is greater than 2, starting to configure a heating device for the nozzle, until b1 is less than 2, stopping configuring the heating device for the nozzle.

5. The method for improving inkjet effect under low temperature conditions according to claim 1, characterized in that: In step S2, a table is created to record the ambient temperature and nozzle temperature before and after the empty spraying, which is used as the nozzle empty spraying temperature increase amplitude at the ambient temperature. The number of empty spraying times i is set for the nozzle heating according to the temperature increase amplitude; and the nozzle heating voltage increase is recorded, and the voltage increase threshold is set. When the nozzle heating voltage increase approaches the threshold, an abnormal alarm is issued.

6. The method for improving inkjet effect under low temperature conditions according to claim 1, characterized in that: The historical temperature rise amplitude q of the table is obtained through historical records. The current temperature rise amplitude is k. The normal amplitude is 5≤qn≤12. When the normal amplitude is exceeded, the nozzle sends a temperature abnormality signal and starts the nozzle configuration heating device until the difference b1 between the front nozzle temperature and the optimal printing nozzle temperature is less than 2, and then the nozzle configuration heating device is stopped.

7. A printing device, comprising at least one processor, at least one memory and computer program instructions stored in the memory, wherein when the computer program instructions are executed by the processor, the method according to any one of claims 1 to 6 is implemented.

8. A storage medium having computer program instructions stored thereon, characterized in that: When the computer program instructions are executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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