A method and system for intelligent adjustment of printing ink for carton

Abstract

The present application belongs to the technical field of printing engineering, and specifically relates to a paper box color printing ink intelligent adjusting method and system, which determines a first solvent compensation amount by calculating a first deviation value and a first derivative thereof, and calculates an ink amount adjusting amount and a second solvent compensation amount by calculating a second deviation value and a second derivative thereof, effectively distinguishes a color density drop caused by insufficient ink amount and a color density drift caused by too fast solvent evaporation, effectively avoids coupling interference of independent adjustment, and realizes collaborative control of viscosity and color density; the present application calculates a solvent diffusion time in combination with an ink path circulation period and a minimum circulation number of experimental calibration, and advances an injection time of the first solvent compensation amount, so that a time of uniform diffusion of the solvent is exactly matched with a time of needing to adjust viscosity, local solvent accumulation and adjustment lag are avoided, solvent utilization efficiency is effectively improved, and continuous stability of printing quality is ensured.

Description

Technical Field

[0001] This invention belongs to the field of printing engineering technology, specifically a method and system for intelligent adjustment of inks for color printing on paper boxes. Background Technology

[0002] In the process of color printing on paper boxes, ink viscosity and color density are two core indicators that determine the quality of the print. Ink viscosity directly affects its transfer performance in the ink path, the uniformity of the ink layer, and the accuracy of dot reproduction; while color density directly measures the saturation and color reproduction accuracy of the printed product, and is a key parameter for judging whether the printed product meets the customer's standards.

[0003] Currently, traditional ink adjustment methods mainly rely on manual adjustments based on the operator's experience. When a color deviation in printed materials is detected, operators typically judge whether to increase or decrease the amount of solvent or ink based on visual inspection or offline testing data and their experience.

[0004] However, the existing technology still has the following limitations: 1. There is a coupling relationship between viscosity and color density. For example, the evaporation of solvent will simultaneously cause the viscosity to increase and the color density to change. In addition, the ink circulation system has an inherent transmission delay, and the ink mixing and diffusion have a large inertia. As a result, the adjustment action is only executed when the deviation is detected. The actual adjustment effect is often delayed by several cycles, which not only wastes solvent, but also cannot guarantee the quality stability in the mass printing process.

[0005] 2. Existing technical solutions typically treat viscosity control and color density control as two independent closed loops for adjustment, lacking a mechanism to predict the changing trends of both. Simply relying on the adjustment of a single indicator will deviate from the expected results. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, embodiments of the present invention provide a method and system for intelligent adjustment of paper box color printing ink, which can effectively solve the problems involved in the prior art.

[0007] The objective of this invention can be achieved through the following technical solutions: In a first aspect, this invention provides a method for intelligent adjustment of paper box color printing ink, comprising: calculating a first deviation value between the real-time viscosity of the ink and a reference viscosity and a second deviation value between the real-time color density and the reference color density.

[0008] The first solvent compensation amount is determined based on the first deviation value and its first derivative, and the ink volume adjustment amount and the second solvent compensation amount are calculated based on the second deviation value and its second derivative.

[0009] Low-volatility solvents are injected based on the first solvent compensation amount, and the solvent diffusion time is calculated in conjunction with the ink path cycle to allow for early injection.

[0010] Adjust the ink fountain roller speed according to the ink volume adjustment amount, and inject high-boiling-point solvent according to the second solvent compensation amount.

[0011] The system acquires real-time viscosity and color density for multiple subsequent sampling periods, calculates the viscosity change rate and color density change rate, and if the ratio of the two is within a preset ratio range, it stores the first solvent compensation amount, the second solvent compensation amount, the ink volume adjustment amount, the diffusion time and the ratio in association with the current printing speed and the ambient temperature and humidity.

[0012] When performing the same printing task, the compensation parameters that match the current working conditions are retrieved, and the real-time viscosity and color density are collected within the first ink path cycle to calculate the working condition deviation and dynamically correct the compensation parameters.

[0013] Secondly, the present invention provides an intelligent adjustment system for paper box color printing ink, comprising: a deviation calculation module for calculating a first deviation value between the real-time viscosity of the ink and the reference viscosity, and a second deviation value between the real-time color density and the reference color density.

[0014] The solvent compensation module determines the first solvent compensation amount based on the first deviation value and its first derivative, and calculates the ink volume adjustment amount and the second solvent compensation amount based on the second deviation value and its second derivative.

[0015] The solvent injection module injects low-volatility solvents based on the first solvent compensation amount, calculates the solvent diffusion time in conjunction with the ink path circulation cycle to inject in advance, adjusts the ink fountain roller speed according to the ink quantity adjustment amount, and injects high-boiling-point solvents according to the second solvent compensation amount.

[0016] The associated storage module obtains the real-time viscosity and color density of multiple subsequent sampling cycles, calculates the viscosity change rate and color density change rate, and if the ratio of the two is within a preset ratio range, it associates and stores the first solvent compensation amount, the second solvent compensation amount, the ink volume adjustment amount, the diffusion time and the ratio with the current printing speed and the ambient temperature and humidity.

[0017] The matching correction module retrieves compensation parameters that match the current working conditions when performing the same printing task, and collects real-time viscosity and color density within the first ink path cycle to calculate the working condition deviation and dynamically correct the compensation parameters.

[0018] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: (1) The present invention determines the first solvent compensation amount by calculating the first deviation value and its first derivative, and calculates the ink amount adjustment amount and the second solvent compensation amount by calculating the second deviation value and its second derivative. This effectively distinguishes the decrease in color density caused by insufficient ink amount and the drift in color density caused by excessive solvent evaporation, effectively avoiding the coupling interference of independent adjustment and realizing the coordinated control of viscosity and color density.

[0019] (2) By performing time alignment processing on the ink path cycle and the printing material transmission delay, this invention ensures that the data used to calculate the deviation is comparable in time, effectively reducing the detection time deviation caused by the different installation positions of the online viscosity sensor and the color density sensor, and providing a data basis for subsequent calculation and collaborative control.

[0020] (3) The present invention calculates the solvent diffusion time by combining the ink path cycle and the minimum number of cycles calibrated by the experiment, and advances the injection time of the first solvent compensation amount, so that the time of uniform solvent diffusion is exactly matched with the time when viscosity needs to be adjusted, avoiding local solvent accumulation and adjustment lag, effectively improving solvent utilization efficiency and ensuring stable printing quality. Attached Figure Description

[0021] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort.

[0022] Figure 1 This is a flowchart of the method of the present invention.

[0023] Figure 2 This is a flowchart for obtaining the operating condition deviation of the present invention.

[0024] Figure 3 This is a schematic diagram of the module connection of the present invention. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Reference Figure 1 As shown, the present invention provides an intelligent adjustment method for paper box color printing ink, including: S1, calculating a first deviation value between the real-time viscosity of the ink and the reference viscosity, and a second deviation value between the real-time color density and the reference color density.

[0027] Considering that the viscosity of ink directly affects its transfer performance and ink layer uniformity during the printing process, while color density is a key indicator for measuring the color saturation and color reproduction accuracy of printed materials.

[0028] Based on this, the specific process for calculating the first deviation value between the real-time viscosity of the ink and the reference viscosity, and the second deviation value between the real-time color density and the reference color density, is as follows: an online viscosity sensor installed in the main circuit section of the ink circulation pipeline via a flange connection collects the viscosity signal of the ink in real time, and an online color density sensor fixedly installed at the printing inspection station collects the color density signal of the printed matter in real time.

[0029] The online viscosity sensor and the online color density sensor are electrically connected to the data acquisition card via signal lines. The data acquisition card samples and converts the acquired analog viscosity and analog color density signals to digital values ​​to obtain real-time viscosity and real-time color density, which are then sent to the controller.

[0030] Read the reference viscosity and reference color density that match the current printing task from the storage unit.

[0031] The storage unit pre-stores reference viscosity and reference color density corresponding to different printing tasks. Each printing task is associated with a unique task identifier, which includes at least the type of printing substrate, ink type, printing speed, and graphic feature parameters. When executing the current printing task, the storage unit is searched for the matching reference viscosity and reference color density based on the current task identifier.

[0032] Considering that the detection positions of the online viscosity sensor and the online color density sensor are different, the controller performs time alignment processing on the real-time viscosity and real-time color density based on the ink path cycle and the delay time of the printed material being transmitted from the inking position to the detection station.

[0033] The first deviation value is obtained by subtracting the real-time viscosity from the reference viscosity, and the second deviation value is obtained by subtracting the real-time color density from the reference color density.

[0034] It should be noted that the preset sampling frequency is determined based on the ink circulation cycle, specifically by obtaining the circulation cycle duration of the current ink circulation pipeline and the preset sampling number within each circulation cycle, and using the ratio of the preset sampling number to the circulation cycle duration as the preset sampling frequency.

[0035] The cycle duration is calculated by real-time detection of ink circulation flow rate by a flow sensor installed in the ink circulation pipeline, combined with the effective volume of the pipeline. The preset sampling number is preferably 5, and the specific value can be adaptively set by the implementer according to the accuracy requirements.

[0036] The reference viscosity and reference color density are obtained through experimental calibration. Specifically, under standard printing conditions, trial printing is carried out using the same batch of standard substrates and standard inks. The viscosity and color density under these conditions are collected by online viscosity sensors and online color density sensors. The average value of multiple measurements is taken as the reference viscosity and reference color density corresponding to this task.

[0037] It should also be noted that the first deviation value between the real-time viscosity and the reference viscosity represents the degree of deviation between the current ink state and the ideal printing conditions, and the second deviation value between the real-time color density and the reference color density reflects the fluctuation of the color reproduction quality of the printed matter, providing feedback for subsequent solvent compensation and ink volume adjustment.

[0038] Considering the significant inertia of ink viscosity changes, relying solely on the current deviation value for adjustment can easily lead to adjustment lag. Therefore, introducing its first derivative can reflect the trend of viscosity changes, thereby achieving proactive adjustment. As for color density, its fluctuation is not only affected by the current ink amount, but also closely related to the acceleration of ink amount changes. By analyzing the second deviation value and its second derivative, it is possible to effectively distinguish between the decrease in color density caused by insufficient ink amount and the color density drift caused by excessive solvent evaporation.

[0039] Based on this, S2 determines the first solvent compensation amount according to the first deviation value and its first derivative, and calculates the ink volume adjustment amount and the second solvent compensation amount according to the second deviation value and its second derivative.

[0040] The specific process for obtaining the first solvent compensation amount, ink quantity adjustment amount, and second solvent compensation amount is as follows: the maximum and minimum values ​​of the first deviation value and its first derivative within the historical time period are obtained, and the maximum and minimum values ​​of the first deviation value and its first derivative at the current moment are obtained. Extreme value normalization processing is used to obtain the standardized viscosity deviation and the standardized viscosity deviation change rate.

[0041] The initial first solvent compensation amount is obtained by multiplying the standardized viscosity deviation and the rate of change of standardized viscosity deviation by the preset proportional coefficient and the preset differential coefficient, respectively, and summing them.

[0042] The second deviation values ​​of the current time and several previous sampling times are obtained and arranged into a second deviation value sequence in time order. At the same time, the second deviation value is obtained by performing second-order difference calculation on the second deviation value and the corresponding acceleration sequence is also arranged in time order.

[0043] For the current sampling time, the second deviation values ​​of the current time and several previous times contained within the preset window are arithmetically averaged, and the calculated average value is used as the filtered color density deviation. Similarly, the corresponding acceleration sequence within the window is arithmetically averaged, and the calculated average value is used as the filtered color density deviation acceleration.

[0044] When the actual amount of data collected is less than the preset window length, the average value is calculated using all the existing data. Once the amount of data reaches the preset window length, the system switches to a fixed window moving average.

[0045] The preset window is exemplarily set to 5 sampling points, and the implementer can adaptively set the numerical value according to the accuracy requirements.

[0046] Obtain the filtered color density deviation at the current moment. A positive deviation value indicates that the color density is too high, and a negative deviation value indicates that the color density is too low. Multiply the deviation value by the preset color density ratio coefficient, and the calculated product is the ink volume adjustment amount.

[0047] Multiply the filtered color density deviation acceleration by the preset acceleration differential coefficient to obtain the basic differential compensation amount, and sum it with the ink volume adjustment amount to obtain the second solvent compensation amount.

[0048] The calculated second solvent compensation amount is compared with the physical limit value of the actuator (such as the minimum and maximum flow rates of the solvent pump). If the second solvent compensation amount is less than the minimum value, the minimum value is taken as the actual second solvent compensation amount. If the second solvent compensation amount is greater than the maximum value, the maximum value is taken as the actual second solvent compensation amount. Otherwise, the current second solvent compensation amount is taken as the actual amount.

[0049] It should be noted that the preset proportional coefficient, preset differential coefficient, preset acceleration differential coefficient, and preset color density proportional coefficient are uniformly obtained through step response experiments combined with the Cohen-Coon tuning formula. Specifically, when the equipment is running normally, the viscosity value and color density value at the same moment are recorded as a reference. At the same moment, a quantitative amount of low-volatile solvent, a quantitative amount of high-boiling-point solvent, and a step change in ink fountain roller speed are injected into multiple sets of ink paths under the same conditions. Real-time viscosity change curves and two color density change curves are obtained respectively.

[0050] For each curve, the time from the start of a step input to the moment when the output begins to change is defined as the delay time, the time from the start of the output change to the point when it reaches 63.2% of the steady-state value is defined as the inertia time, and the ratio of the steady-state change of the output to the step change of the input is defined as the process gain.

[0051] Substitute the delay time, inertia time, and process gain into the Cohen-Coon tuning formula to calculate the corresponding preset proportional coefficient, preset differential coefficient, preset acceleration differential coefficient, and preset color density proportional coefficient.

[0052] It should also be noted that when the system is first running and there is no historical data, the deviation value is used directly for calculation instead of normalization. Once enough data has been accumulated to calculate the extreme value normalization data, the system will switch to extreme value normalization.

[0053] S3. Inject low-volatility solvent based on the first solvent compensation amount, and calculate the solvent diffusion time in conjunction with the ink path cycle to inject in advance.

[0054] Considering that the injection of low-volatility solvents does not produce an immediate regulating effect, it is necessary for them to undergo a mixing and diffusion process in the ink circulation pipeline before they can be evenly distributed in the ink system and play a role in stabilizing viscosity. If the solvent is injected immediately when the viscosity deviation is detected, the regulating effect will be delayed due to the diffusion delay. Therefore, it is necessary to calculate the solvent diffusion time in combination with the ink circulation cycle and advance the injection time.

[0055] The process of calculating the solvent diffusion time in conjunction with the ink path circulation cycle to inject in advance is as follows: obtain the current circulation cycle duration of the ink path circulation pipeline, and determine the minimum number of cycles required for the solvent to complete uniform mixing in the ink path.

[0056] The minimum number of cycles is obtained through experimental calibration. Specifically, under laboratory conditions, a preset amount of tracer solvent (the same type of solvent as oil-soluble dyes) is injected into the ink circulation pipeline. Multiple online viscosity sensors are installed at different positions in the circulation pipeline to detect the number of cycles required for the tracer solvent concentration to reach a uniform distribution. This number is taken as the minimum number of cycles and stored in the controller in association with parameters such as ink type, solvent type, and pipeline structure. When executing a printing task, the controller retrieves the corresponding minimum number of cycles from the storage unit according to the ink type and solvent type currently being used.

[0057] The product of the minimum number of cycles and the current cycle duration is used as the solvent diffusion time, and the injection time of the first solvent compensation amount is advanced by the solvent diffusion time.

[0058] The process of controlling the injection time in advance is as follows: the current time is obtained and combined with the solvent diffusion time, and the time difference between the two is used as the advance injection time; when the system time arrives, the controller triggers the solvent injection command and performs the injection operation of the first solvent compensation amount.

[0059] Understandably, if the current time is close to or exceeds the theoretically optimal injection time, the start time of the current ink path cycle and the start time of the next cycle are obtained, and the injection time is delayed to the start time of the next cycle to ensure that the solvent injection and ink path cycle are synchronized.

[0060] It should be noted that the solvent needs a certain amount of time to mix and diffuse in the ink path. If it is injected immediately at the detection time, the actual effective time of the solvent will be delayed, which will cause the viscosity deviation to persist or even worsen, further leading to adjustment lag. By combining the ink path cycle and advancing the injection time, the time when the solvent completes diffusion is matched with the time when the deviation needs to be adjusted, avoiding local accumulation and uneven mixing, and achieving fine control of viscosity.

[0061] Considering that insufficient or excessive ink output from the ink fountain roller can lead to changes in the ink coverage thickness on the printed surface; and that an imbalance in the evaporation rate of the solvent in the ink can cause changes in the ink's fluidity and transfer characteristics, thereby affecting the stability of color density reproduction.

[0062] Based on this, the ink fountain roller speed is adjusted according to the ink volume adjustment amount, and a high-boiling-point solvent is injected according to the second solvent compensation amount.

[0063] The process of adjusting the ink fountain roller speed according to the ink volume adjustment amount is as follows: the calculated ink volume adjustment amount is substituted into the preset ink volume-speed mapping function to calculate the target speed adjustment value of the ink fountain roller.

[0064] The expression for the preset ink volume-speed mapping function is: .

[0065] in, Indicates the target speed adjustment value. Indicates the ink volume adjustment amount. This represents the correction factor. This represents the intercept constant.

[0066] In this formula, This constitutes a linear term that is directly proportional to the amount of ink volume adjustment; the larger the amount of ink volume adjustment, the larger the required speed adjustment value. It provides translation corrections for linear functions to compensate for inherent nonlinearities or initial offsets in the system, making the mapping relationship more consistent with actual working conditions.

[0067] The overall formula establishes a linear mapping relationship, adjusting the ink volume. Target speed adjustment value for converting to ink fountain roller This enables a quantitative transformation from ink volume demand to actuator control.

[0068] Adjust value according to target speed Generate a drive signal to adjust the speed of the ink fountain roller drive mechanism.

[0069] It should be noted that the ink volume adjustment amount The acquisition process is as follows: obtain the current ink supply volume, calculate the theoretical ink requirement based on the area coverage of the printed image, and obtain the ink volume adjustment amount by subtracting the two. .

[0070] The correction coefficient and intercept constant This was determined through experimental calibration, specifically by selecting multiple different ink volume adjustment values. As input, for each setting Manually adjust the ink fountain roller speed and record the actual speed adjustment value that corresponds to the ink reaching the required level. .

[0071] by Let x be the x-coordinate. Using the ordinate y, we fit the equation of the straight line. Calculations yielded and .

[0072] It should also be noted that the ink volume adjustment amount and the second solvent compensation amount calculated based on the second deviation value and its second derivative are used to adjust the ink fountain roller speed to change the ink supply amount, and a high-boiling-point solvent is injected to slow down the solvent evaporation rate. The two work together to achieve rapid response and long-term effective control of color density deviation.

[0073] S4. Obtain the real-time viscosity and color density of multiple subsequent sampling cycles, calculate the viscosity change rate and color density change rate, and if the ratio of the two is within the preset ratio range, then store the first solvent compensation amount, the second solvent compensation amount, the ink volume adjustment amount, the diffusion time and the ratio in association with the current printing speed and the ambient temperature and humidity.

[0074] Considering that the immediate response after a single adjustment only reflects the control effect at the current moment and cannot verify the continuous effectiveness and stability of the adjustment parameters in subsequent operation, and that the changes in ink viscosity and color density have temporal continuity and dynamism, it is necessary to evaluate the evolution trend of the ink state after adjustment through continuous monitoring of multiple sampling cycles.

[0075] Based on this, the specific process for calculating the viscosity change rate and the color density change rate is as follows: after completing the injection and adjustment of the first solvent compensation amount, the second solvent compensation amount and the ink amount adjustment amount, the real-time viscosity and real-time color density at multiple sampling times are continuously obtained at a preset sampling period, and the viscosity time series and color density time series are constructed respectively.

[0076] Both the viscosity time series and the color density time series were linearly fitted using the least squares method, and the slopes were calculated. The corresponding slopes were used as the rates of change of viscosity and color density, respectively.

[0077] The specific process of the associated storage is as follows: calculate the ratio of the viscosity change rate to the color density change rate. If the ratio is within a preset ratio range, the current working condition is determined to be valid data; otherwise, it is marked as abnormal data for subsequent analysis.

[0078] The effective data, including the first solvent compensation amount, the second solvent compensation amount, the ink volume adjustment amount, the solvent diffusion time, and the ratio, are recorded as a set of adjustment parameters. At the same time, the printing speed, ambient temperature, and ambient humidity at the current moment are collected as the working condition labels for this set of adjustment parameters. The above adjustment parameters and working condition labels are encapsulated into a complete data record according to a predefined data structure and stored. The data structure includes at least the following fields: task identifier field, timestamp field, solvent compensation amount field, ink volume adjustment amount field, diffusion time field, rate ratio field, printing speed field, ambient temperature field, and ambient humidity field.

[0079] It should be noted that the preset sampling period is calculated, specifically as follows: the theoretical highest frequency of ink characteristic changes in the ink circulation pipeline is obtained, where the highest frequency is the ratio of the printing press's highest operating speed to the spacing between printing units. The theoretical lowest sampling frequency is determined according to Shannon's sampling theorem, and then the theoretical lowest sampling frequency is converted into the theoretical maximum sampling period. Half of the theoretical maximum sampling period is taken as the preset sampling period.

[0080] The preset ratio range is dynamically generated based on the statistical distribution of historical valid data. Specifically, during the execution of the same printing task, multiple sets of data on the ratio of viscosity change rate to color density change rate, which have been determined to be valid data, are obtained, and the mean and standard deviation of the multiple sets of data are calculated. The ratio range width coefficient is set according to the control confidence level requirements. The width coefficient is exemplarily set to a value range of 1 to 3. The larger the value, the wider the range and the more lenient the data screening.

[0081] The lower limit of the preset ratio range is the mean minus the product of the width coefficient and the standard deviation, and the upper limit of the preset ratio range is the mean plus the product of the width coefficient and the standard deviation.

[0082] It should also be noted that by collecting data and analyzing trends over multiple consecutive sampling periods, the evaluation of control effectiveness is transformed from a single-point instantaneous response to a dynamic development process, effectively verifying the long-term stability of the adjustment parameters and avoiding misjudgments caused by short-term fluctuations. Using the ratio of viscosity change rate to color density change rate as a synergy criterion, a quantitative assessment of the matching degree between ink rheological properties and color reproduction performance is achieved. Effective adjustment parameters are associated with and stored with operating parameters such as printing speed, ambient temperature and humidity, so that subsequent identical printing tasks can quickly retrieve the most suitable effective adjustment parameters based on the current operating conditions.

[0083] S5. When performing the same printing task, retrieve the compensation parameters that match the current working conditions, and collect the real-time viscosity and color density within the first ink path cycle to calculate the working condition deviation and dynamically correct the compensation parameters.

[0084] Considering that although the compensation parameters stored in the experience library match the current printing task, their corresponding operating condition labels (such as printing speed, ambient temperature and humidity) may differ from the current actual operating conditions, directly calling historical parameters without correction may cause the control effect to deviate from expectations.

[0085] It should be noted that if there are no compensation parameters that match the current working conditions, the initial adjustment is made based on experience. After the initial adjustment is completed and its effectiveness is verified, the compensation parameters and corresponding working condition information of the adjustment process are associated and stored.

[0086] Reference Figure 2 As shown, based on this, the specific process for calculating the working condition deviation is as follows: within the first ink path cycle, the real-time viscosity and real-time color density are continuously collected at multiple sampling times at a preset sampling frequency.

[0087] The first real-time deviation between the real-time viscosity and the reference viscosity at each sampling time is calculated to construct the first real-time deviation sequence, and the second real-time deviation between the real-time color density and the reference color density is constructed to construct the second real-time deviation sequence.

[0088] The mean values ​​of the first real-time deviation sequence and the second real-time deviation sequence are calculated respectively, and the average viscosity deviation and average color density deviation are obtained accordingly.

[0089] Multiply the average viscosity deviation and average color density deviation by their respective weighting coefficients, and sum them to obtain the deviation of the current operating condition from the reference operating condition.

[0090] The weighting coefficients are directly assigned values ​​based on the control objectives. If the printing task requires high color reproduction accuracy (such as color packaging box printing), then the color density deviation weighting coefficient is set to be larger and the viscosity deviation weighting coefficient is set to be smaller. For example, the color density deviation weighting coefficient is 0.7 and the viscosity deviation weighting coefficient is 0.3. If the ink layer uniformity and fluidity requirements are high (such as large-area solid printing), then the viscosity deviation weighting coefficient is set to be larger and the color density deviation weighting coefficient is set to be smaller. For example, the color density deviation weighting coefficient is 0.4 and the viscosity deviation weighting coefficient is 0.6.

[0091] The process of dynamically correcting the compensation parameters is as follows: retrieve the corresponding compensation parameters, which include: the first solvent compensation amount, the second solvent compensation amount, and the ink amount adjustment amount, and multiply them by the correction coefficients respectively to obtain the dynamic correction compensation parameters under the current operating conditions.

[0092] The correction coefficient is determined based on the relative relationship between the working condition deviation and the preset ratio range. Specifically, the current working condition deviation is obtained, and the preset ratio range associated with the printing task is read. When the working condition deviation is within the preset ratio range, it indicates that the deviation between the current working condition and the benchmark working condition is within the normal fluctuation range of historical valid data, and there is no need to make significant corrections to the compensation parameters. The correction coefficient is set to 1.

[0093] When the deviation of the operating condition is less than the lower limit of the preset proportional range or greater than the upper limit of the preset proportional range, the ratio of the deviation of the operating condition to the lower limit of the preset proportional range is used as the correction coefficient.

[0094] The dynamically corrected compensation parameters replace the original retrieved compensation parameters and are used as the actual execution parameters for the current printing task to perform solvent injection and ink volume adjustment for the next ink cycle.

[0095] In subsequent ink path cycles, real-time viscosity and real-time color density are continuously collected. If new operating condition deviations are detected, the above correction process is repeated.

[0096] It should be noted that data is collected in real time and the working condition deviation is calculated during the first ink path cycle. The deviation between the current actual working condition and the historical working condition is quantitatively evaluated, and the retrieved parameters are adjusted accordingly. This effectively solves the problem of control effect deviation. The first ink path cycle refers to the first complete cycle after the start of this printing task and the completion of the initial ink supply and operation.

[0097] Reference Figure 3 As shown, in a second aspect, the present invention provides an intelligent adjustment system for paper box color printing ink, comprising: a deviation calculation module for calculating a first deviation value between the real-time viscosity of the ink and a reference viscosity, and a second deviation value between the real-time color density and the reference color density.

[0098] The solvent compensation module determines the first solvent compensation amount based on the first deviation value and its first derivative, and calculates the ink volume adjustment amount and the second solvent compensation amount based on the second deviation value and its second derivative.

[0099] The solvent injection module injects low-volatility solvents based on the first solvent compensation amount, calculates the solvent diffusion time in conjunction with the ink path circulation cycle to inject in advance, adjusts the ink fountain roller speed according to the ink quantity adjustment amount, and injects high-boiling-point solvents according to the second solvent compensation amount.

[0100] The associated storage module obtains the real-time viscosity and color density of multiple subsequent sampling cycles, calculates the viscosity change rate and color density change rate, and if the ratio of the two is within a preset ratio range, it associates and stores the first solvent compensation amount, the second solvent compensation amount, the ink volume adjustment amount, the diffusion time and the ratio with the current printing speed and the ambient temperature and humidity.

[0101] The matching correction module retrieves compensation parameters that match the current working conditions when performing the same printing task, and collects real-time viscosity and color density within the first ink path cycle to calculate the working condition deviation and dynamically correct the compensation parameters.

[0102] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined by the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A method for intelligent adjustment of inks used in color printing on paper boxes, characterized in that, include: Calculate the first deviation between the real-time viscosity and the reference viscosity of the ink, and the second deviation between the real-time color density and the reference color density; The first solvent compensation amount is determined based on the first deviation value and its first derivative, and the ink volume adjustment amount and the second solvent compensation amount are calculated based on the second deviation value and its second derivative. Low-volatility solvents are injected based on the first solvent compensation amount, and the solvent diffusion time is calculated in conjunction with the ink path circulation cycle to allow for early injection. Adjust the ink fountain roller speed according to the ink volume adjustment amount, and inject high-boiling-point solvent according to the second solvent compensation amount; The system acquires the real-time viscosity and color density of multiple subsequent sampling periods, calculates the viscosity change rate and color density change rate, and if the ratio of the two is within a preset ratio range, it stores the first solvent compensation amount, the second solvent compensation amount, the ink volume adjustment amount, the diffusion time and the ratio in association with the current printing speed and the ambient temperature and humidity. When performing the same printing task, the compensation parameters that match the current working conditions are retrieved, and the working condition deviation is calculated by collecting real-time viscosity and color density within the first ink path cycle, and the compensation parameters are dynamically corrected.

2. The intelligent adjustment method for paper box color printing ink according to claim 1, characterized in that, The specific process for calculating the first deviation value between the real-time viscosity and the reference viscosity of the ink, and the second deviation value between the real-time color density and the reference color density, is as follows: The viscosity signal of the ink is collected in real time by an online viscosity sensor installed in the ink circulation pipeline, and the color density signal of the printed matter is collected in real time by an online color density sensor installed at the printing inspection station. The viscosity signal and color density signal are converted from analog to digital to obtain real-time viscosity and real-time color density, respectively. Read the reference viscosity and reference color density that match the current printing task from the storage unit; The first deviation value is obtained by subtracting the real-time viscosity from the reference viscosity, and the second deviation value is obtained by subtracting the real-time color density from the reference color density.

3. The intelligent adjustment method for paper box color printing ink according to claim 1, characterized in that, The specific process for obtaining the first solvent compensation amount, the ink volume adjustment amount, and the second solvent compensation amount is as follows: The first deviation value and its first derivative are normalized by extreme value to obtain the standardized viscosity deviation and the rate of change of standardized viscosity deviation. The first solvent compensation amount is calculated by proportional-derivative control and then subjected to amplitude limiting. The second deviation value and its second derivative are subjected to moving average filtering to obtain the filtered color density deviation and color density deviation acceleration. The ink volume adjustment amount is obtained by calculating the color density deviation through proportional control. The color density deviation acceleration is combined with the ink volume adjustment amount and the second solvent compensation amount is obtained by calculating through differential control. The second solvent compensation amount is then subjected to amplitude limiting.

4. The intelligent adjustment method for paper box color printing ink according to claim 1, characterized in that, The process of calculating the solvent diffusion time based on the ink circulation cycle to inject in advance is as follows: Obtain the current cycle time of the ink circulation pipeline and determine the minimum number of cycles required for the solvent to be uniformly mixed in the ink path; The product of the minimum number of cycles and the current cycle duration is used as the solvent diffusion time, and the injection time of the first solvent compensation amount is advanced by the solvent diffusion time.

5. The intelligent adjustment method for paper box color printing ink according to claim 1, characterized in that, The process of adjusting the ink fountain roller speed according to the ink volume adjustment is as follows: Substitute the calculated ink volume adjustment amount into the preset ink volume-speed mapping function to calculate the target speed adjustment value of the ink fountain roller. A drive signal is generated based on the target speed adjustment value to adjust the speed of the ink fountain roller drive mechanism.

6. The intelligent adjustment method for color printing ink on paper boxes according to claim 1, characterized in that, The specific process for calculating the viscosity change rate and the color density change rate is as follows: The real-time viscosity and real-time color density are continuously acquired at multiple sampling times with a preset sampling period, and the viscosity time series and color density time series are constructed respectively. The viscosity time series and color density time series were linearly fitted, and the corresponding slopes were used as the rates of change of viscosity and color density, respectively.

7. The intelligent adjustment method for paper box color printing ink according to claim 1, characterized in that, The specific process of the associated storage is as follows: Calculate the ratio of viscosity change rate to color density change rate. If the ratio is within a preset ratio range, the current operating condition is considered valid data. Establish a one-to-one correspondence between the effective data of the first solvent compensation amount, the second solvent compensation amount, the ink volume adjustment amount, the solvent diffusion time, and the ratio, and store them with the current printing speed, the current ambient temperature, and the current ambient humidity.

8. The intelligent adjustment method for color printing ink on paper boxes according to claim 1, characterized in that, The specific process for calculating the operating condition deviation is as follows: Within the first ink path cycle, real-time viscosity and real-time color density are continuously collected at multiple sampling times at a preset sampling frequency; Calculate the first real-time deviation between the real-time viscosity and the reference viscosity at each sampling time and construct the first real-time deviation sequence; and calculate the second real-time deviation between the real-time color density and the reference color density and construct the second real-time deviation sequence. The first and second real-time deviation sequences are averaged to obtain the average viscosity deviation and average color density deviation. The deviation of the current operating condition from the reference operating condition is obtained by linearly weighting and summing the average viscosity deviation and the average color density deviation.

9. The intelligent adjustment method for paper box color printing ink according to claim 8, characterized in that, The process of dynamically correcting the compensation parameters is as follows: The corresponding compensation parameters are retrieved, including the first solvent compensation amount, the second solvent compensation amount, and the ink amount adjustment amount, and then multiplied by the correction coefficient to obtain the dynamic correction compensation parameters under the current working conditions. The dynamic correction compensation parameter replaces the original retrieved compensation parameter and is used as the actual execution parameter for the current printing task to perform solvent injection and ink volume adjustment for the next ink path cycle. In subsequent ink path cycles, real-time viscosity and real-time color density are continuously collected. If new operating condition deviations are detected, the above correction process is repeated.

10. A paper box color printing ink intelligent adjustment system, characterized in that, include: The deviation calculation module calculates the first deviation value between the real-time viscosity of the ink and the reference viscosity, and the second deviation value between the real-time color density and the reference color density. The solvent compensation module determines the first solvent compensation amount based on the first deviation value and its first derivative, and calculates the ink volume adjustment amount and the second solvent compensation amount based on the second deviation value and its second derivative. The solvent injection module injects low-volatility solvent based on the first solvent compensation amount, calculates the solvent diffusion time in conjunction with the ink path circulation cycle to inject in advance, adjusts the ink fountain roller speed according to the ink quantity adjustment amount, and injects high-boiling-point solvent according to the second solvent compensation amount. The associated storage module acquires real-time viscosity and color density for multiple subsequent sampling cycles, calculates the viscosity change rate and color density change rate, and if the ratio of the two is within a preset ratio range, it associates and stores the first solvent compensation amount, the second solvent compensation amount, the ink volume adjustment amount, the diffusion time and the ratio with the current printing speed and the ambient temperature and humidity; the matching correction module retrieves the compensation parameters that match the current working conditions when performing the same printing task, and collects real-time viscosity and color density in the first ink path cycle, calculates the working condition deviation, and dynamically corrects the compensation parameters.

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