Intaglio printing tension control method based on tension coupling relation

Abstract

The intaglio printing tension control method based on the tension coupling relation comprises the steps that a multi-span tension coupling model is established according to physical parameters of an intaglio printing machine; tension values of all spans are collected in real time through all tension sensors and transmitted to a PID controller, all encoders measure the angular speed of all rollers and transmit the angular speed to the PID controller, and the PID controller calculates the movement speed of a base material; inputting the real-time tension value, the angular velocity of the roller and the movement velocity of the base material into a multi-span tension coupling model, and calculating the theoretical value of the tension of each span; comparing the theoretical tension value with a preset tension target value to generate an error signal; based on the error signal, the roller angular velocity of the current span and the adjacent span is dynamically adjusted through a PID controller, so that the actual tension value approaches the target value; closed-loop feedback control is realized, and tension of each span is ensured to be stable. According to the intaglio printing tension control method, tension of all spans is accurately controlled, the anti-interference capacity is improved, and then the quality and production efficiency of printed electronic products are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of intaglio printing equipment, and relates to a method for controlling the tension of intaglio printing based on the tension coupling relationship. Background Art

[0002] In the modern printing industry, due to its high-precision and high-efficiency characteristics, the intaglio printing technology is widely used in various large-scale and continuous printing production processes, such as in the large-scale and continuous production of printed electronic products. However, with the rapid development of printed electronic technology, the traditional tension control system of intaglio printing equipment faces many challenges, such as large tension fluctuations and weak anti-interference ability. These problems seriously affect the quality and production efficiency of printed products. In the actual printing process, the stability of the tension is directly related to the clarity of the printed pattern, the accuracy of overprinting, and the degree of material loss. Excessive tension fluctuations may lead to blurred printed patterns, inaccurate overprinting, and even cause stretching or breakage of the material, thus increasing production costs and the scrap rate. In addition, during the operation of the printing equipment, it will be affected by various interference factors, such as changes in environmental temperature and humidity, mechanical vibration, and electrical system noise. These interference factors will cause deviations in the tension control system, further exacerbating the tension fluctuations and reducing the printing quality.

[0003] Therefore, researching and developing a tension control method that can accurately control the tension and improve the anti-interference ability is of great significance for improving the quality and production efficiency of printed electronic products. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for controlling the tension of intaglio printing based on the tension coupling relationship, accurately control the tension of each span, improve the anti-interference ability, and improve the quality and production efficiency of printed electronic products.

[0005] The technical solution of the present invention is a method for controlling the tension of intaglio printing based on the tension coupling relationship, which is specifically implemented according to the following steps: Step 1: Tension sensors and encoders are respectively arranged on each roller of the intaglio printing press, and each tension sensor and encoder are respectively connected to a PID controller; Step 2: Establish a multi-span tension coupling model according to the physical parameters of the intaglio printing press; Step 3: The real-time tension values of each span are collected by each tension sensor and transmitted to the PID controller, and the angular velocity of each roller is measured by each encoder and transmitted to the PID controller. The PID controller calculates the moving speed of the substrate; Step 4: Input the real-time tension value, the angular velocity of the roller, and the moving speed of the substrate into the multi-span tension coupling model to calculate the theoretical value of the tension of each span; Step 5: Compare the theoretical tension value with the preset tension target value to generate an error signal; Step 6: Based on the error signal, dynamically adjust the angular velocities of the current and adjacent rollers through a PID controller to make the actual tension value approach the target value; Step 7: Repeat Steps 3 to 6 to achieve closed-loop feedback control and ensure the stability of the tension in each span.

[0006] The features of the present invention also lie in that In Step 2, the physical parameters include the elastic modulus, cross-sectional area, distance between adjacent rollers, roller radius, roller angular velocity, and the moving speed of the substrate.

[0007] In Step 2, the multi-span tension coupling model is:

[0008] Where: ; L i represents the center distance between adjacent rollers in the i-th span; T i (t): the tension in the i-th span; ω i (t): the angular velocity of the i-th printing roller; R i : the radius of the i-th printing roller; AE: the product of the cross-sectional area and elastic modulus of the material; T i-1 (t): the tension in the previous span; R i-1 : the radius of the previous roller; ω i-1 (t): the angular velocity of the previous roller; t: the time variable, representing the instantaneous state of the dynamic process.

[0009] In Step 3, the calculation formula for the moving speed of the substrate is as follows: v i ( t )= R i ω i ( t ).

[0010] , In Step 5, the calculation formula for the error signal is: Δ T i ( t )= T i ,target− Ti , model( t ) Among them, T i , the target is the preset target tension.

[0011] In step 6, the adjustment of the drum angular velocity needs to consider the coupling relationship between the current span and the adjacent spans at the same time. The adjustment formula is:

[0012] Among them, K p , K i , K d are PID control parameters, which are calibrated through experiments.

[0013] The beneficial effect of the present invention is that The gravure printing tension control method based on the tension coupling relationship of the present invention in a gravure printing device establishes a multi-span tension coupling model according to the physical parameters of the gravure printing press, fully considering the influence of the coupling relationship between adjacent spans on the tension of each span, so as to achieve precise control of the multi-span tension system. Specific embodiments

[0014] The present invention will be described in detail below with reference to specific embodiments.

[0015] During the gravure printing process, the change in the drum speed will not only affect the tension of the current span, but also cause tension fluctuations in the subsequent spans. The amplitude of this fluctuation will gradually decrease, and the peak time will be delayed in turn. The change in the drum speed has a significant impact on the tension of the subsequent spans, but this impact will gradually weaken as the number of spans increases. There is an obvious coupling relationship between the tensions of adjacent spans, and the change in the tension of the previous span will directly affect the tension of the subsequent span. This coupling relationship is inevitable in the multi-span tension system and must be fully considered in the tension control system.

[0016] During the gravure printing process, tension is a key factor to ensure printing quality and production efficiency. The stability and precise control of tension directly affect the clarity of the printed pattern, the accuracy of overprinting, and the degree of material loss. Tension is generated by stretching the substrate between two adjacent drums. Its magnitude depends on various factors, including the material properties of the substrate (such as elastic modulus, cross-sectional area), the geometric parameters of the drums (such as radius, spacing), and the motion state of the substrate (such as speed, acceleration). In the actual printing process, the change in tension is not only affected by the drum speed and tension of the current span, but also by the coupling effect of the tension of adjacent spans, as well as the influence of the drying equipment on the mechanical properties of the substrate.

[0017] Therefore, tension control is a crucial link to ensure the stability of the printing process and product quality. Its core objective is to keep the cross-tensions stable at the set values to meet the strict requirements of the printing process. Specifically, it is necessary to ensure that the cross-tensions remain stable and avoid excessive fluctuations; the system should have the ability to quickly respond to input changes and reach a stable state rapidly; the tension should be precisely controlled at the set value, and the error should be strictly controlled within the allowable range.

[0018] Embodiment 1 The gravure printing tension control method based on the tension coupling relationship of the present invention is specifically implemented according to the following steps: Step 1: Tension sensors and encoders are respectively arranged on each roller of the gravure printing press, and each tension sensor and encoder are respectively connected to a PID controller; Step 2: Establish a multi-span tension coupling model based on the physical parameters of the gravure printing press; Step 3: The cross-tension values are collected in real time by each tension sensor and transmitted to the PID controller, and the angular velocities of each roller are measured by each encoder and transmitted to the PID controller. The PID controller calculates the moving speed of the substrate; Step 4: Input the real-time tension value, the angular velocity of the roller, and the moving speed of the substrate into the multi-span tension coupling model to calculate the theoretical values of the cross-tensions; Step 5: Compare the theoretical tension value with the preset tension target value to generate an error signal; Step 6: Based on the error signal, the angular velocities of the current span and the adjacent spans are dynamically adjusted by the PID controller to make the actual tension value approach the target value; Step 7: Repeat Steps 3 to 6 to achieve closed-loop feedback control and ensure the stability of the cross-tensions.

[0019] Embodiment 2 On the basis of Embodiment 1, in order to accurately describe the tension control of the multi-span tension coupling relationship, the physical parameters in Step 2 include the elastic modulus (E), cross-sectional area (A), distance between adjacent rollers (L i ), roller radius (R i ), roller angular velocity (ω i ), and moving speed of the substrate (v i ).

[0020] The established multi-span tension coupling model needs to start from the following aspects: 1. Physical properties of the substrate The physical properties of the substrate are one of the key factors affecting the tension. The elastic modulus (E) and cross-sectional area (A) of the material determine its stress-strain characteristics during the stretching process. The elastic modulus reflects the rigidity of the material, that is, the ability of the material to resist deformation in the elastic deformation stage, while the cross-sectional area determines the tensile strength of the material. In the tension model, the product of the elastic modulus and cross-sectional area of the material (AE) is an important parameter, which directly affects the magnitude of the tension. Specifically, the higher the elastic modulus, the greater the tension generated by the material under the same strain; the larger the cross-sectional area, the stronger the tensile ability of the material, and the tension will also increase accordingly.

[0021] 2. Geometric parameters of the roller The geometric parameters of the roller, such as the radius (R) and spacing (L), play an important role in the distribution and transmission of tension. The size of the roller radius directly affects the contact length and stretching degree of the substrate. A larger roller radius can reduce the bending stress of the substrate, thereby reducing the tension fluctuation. At the same time, the roller spacing (that is, the length of the substrate between two rollers) also affects the transmission efficiency of the tension. A shorter spacing can reduce the cumulative effect of the tension, while a longer spacing may lead to uneven distribution of the tension.

[0022] 3. Motion state of the substrate The motion state of the substrate, including the speed (v) and acceleration (a), is the direct driving force for the tension change. During the printing process, the speed change of the roller will cause the stretching or relaxation of the substrate, resulting in the change of the tension. In addition, the acceleration of the substrate will also have a transient impact on the tension. For example, when the roller suddenly accelerates, the substrate will be quickly stretched, resulting in a sharp increase in the tension; while when the roller decelerates, the substrate will relax and the tension will decrease.

[0023] 4. Coupling relationship between adjacent spans In a multi-span tension system, there is an obvious coupling relationship between the tensions of adjacent spans. The tension change in the previous span will directly affect the tension in the next span. This coupling effect is caused by the continuity of the substrate and the interaction between the rollers. Specifically, when the tension in the previous span increases, the substrate will be further stretched, resulting in an increase in the tension in the next span; conversely, when the tension in the previous span decreases, the tension in the next span will also decrease accordingly. Therefore, when establishing a tension control method, this coupling relationship must be fully considered to ensure the accuracy and integrity of the method.

[0024] Based on the above factors, for the i-th span, its tension control method can be expressed as:

[0025] where:

[0026] Li : Center distance between adjacent rollers in the i-th span; T i (t): Tension in the i-th span; ω i (t): Angular velocity of the i-th printing roller; R i : Radius of the i-th printing roller; AE: Product of the cross-sectional area and elastic modulus of the material; T i-1 (t): Tension in the previous span; R i-1 : Radius of the previous roller; ω i-1 (t): Angular velocity of the previous roller; t: Time variable, representing the instantaneous state of the dynamic process. That is, a multi-span tension coupling model is obtained.

[0027] Example 3 Based on Example 2, in step 3, the calculation formula for the substrate movement speed is as follows: v i ( t ) = R i ω i ( t ).

[0028] Example 4 Based on Example 3, in step 5, the error signal calculation formula is: Δ T i ( t ) = T i , target − T i , model( t ) Where, T i , target is the preset target tension.

[0029] Example 5 Based on Example 4, in step 6, the adjustment of the roller angular velocity needs to consider the coupling relationship between the current span and the adjacent span simultaneously. The adjustment formula is:

[0030] Where K p , K i , K d are PID control parameters, calibrated through experiments.

[0031] Example 6 For the gravure printing tension control method based on the tension coupling relationship of the present invention, the core lies in combining the multi-span tension coupling model with closed-loop feedback control. The specific process is as follows: 1. Data acquisition: The actual tension values (T i (t)) of each span are obtained in real time through a tension sensor, and the angular velocity of the roller (ω i (t)) is measured by an encoder, and the moving speed of the substrate ( v i ( t ) = R i ω i ( t )).

[0032] 2. Model calculation: The real-time data is input into the coupling model to calculate the theoretical tension value ( T i ,model( t )).

[0033] 3. Error feedback: Calculate the error signal Δ T i ( t ) = T i ,target − T i ,model( t ), where T i ,target is the preset target tension.

[0034] 4. Dynamic adjustment: Generate an angular velocity adjustment amount (Δ ωi ( t )) through a PID controller, and synchronously adjust the angular velocity of the current span and the adjacent spans to offset the coupling effect.

[0035] For the gravure printing tension control method based on the tension coupling relationship of the present invention, by considering the physical properties of the substrate, the geometric parameters of the rollers, the motion state of the substrate, and the coupling relationship between adjacent spans, it can accurately describe the tension changes of each span in the multi-span tension system, thereby achieving precise control of the tension. Through the tension control method designed based on the coupling relationship of the multi-span tension system, precise control of the multi-span tension system can be achieved. This tension control method can meet the control objectives of gravure printing equipment, significantly improve the accuracy and stability of tension control, and thus effectively improve the quality and production efficiency of printed electronic products.

[0036] The gravure printing tension control method based on the tension coupling relationship of the present invention has the advantages that it realizes the precise control of the tension system of the gravure printing equipment, significantly improves the accuracy of tension control and the anti-interference ability, thereby effectively improving the quality and production efficiency of printed electronic products, provides strong technical support for the technological upgrading of gravure printing equipment and the development of the printed electronics industry, and has broad application prospects and important practical significance.

Claims

1. A gravure printing tension control method based on tension coupling relationship, characterized in that: The steps are: S1: A tension sensor and an encoder are arranged on each cylinder of the gravure printing machine, and each tension sensor and encoder is connected to a PID controller respectively; S2: Establish a multi-span tension coupling model based on the physical parameters of the gravure printing press; S3: Each tension sensor collects each span tension value in real time and transmits it to the PID controller, each encoder measures the angular velocity of each roller and transmits it to the PID controller, and the PID controller calculates the movement speed of the substrate; S4: input the real-time tension value, the roller angular velocity, and the substrate movement speed into the multi-span tension coupling model to calculate the theoretical value of each span tension; S5: Compare the theoretical tension value with the preset tension target value to generate an error signal; S6: Based on the error signal, the PID controller dynamically adjusts the roller angular velocity of the current span and the adjacent span so that the actual tension value approaches the target value; S7: Repeat S3 to S6 to implement closed-loop feedback control and ensure the stability of the tension in each span.

2. The gravure printing tension control method based on tension coupling relationship according to claim 1, characterized in that: In S2, the physical parameters include elastic modulus, cross-sectional area, distance between adjacent rollers, roller radius, roller angular velocity and substrate movement speed of the substrate.

3. The gravure printing tension control method based on tension coupling relationship according to claim 1, characterized in that: In S2, the multi-span tension coupling model is: in: L i represents the center distance between adjacent rollers in the i-th span; T i (t): tension of the i-th span; ω i (t): angular velocity of the i-th printing cylinder; R i : The radius of the i-th printing cylinder; AE: product of the cross-sectional area and elastic modulus of the material; T i-1 (t): tension of the previous span; R i-1 : The radius of the previous roller; ω i-1 (t): angular velocity of the previous roller; t: time variable, representing the instantaneous state of the dynamic process.

4. The gravure printing tension control method based on tension coupling relationship according to claim 3, characterized in that: In the multi-span tension coupling model, .

5. The gravure printing tension control method based on tension coupling relationship according to claim 3, characterized in that: In S3, the calculation formula of the substrate movement speed is as follows: v i ( t )= R i ω i ( t ).

6. The gravure printing tension control method based on tension coupling relationship according to claim 1, characterized in that: In S5, the error signal calculation formula is: Δ T i ( t )= T i ,target− T i ,model( t ) in, T i ,target is the preset target tension.

7. The gravure printing tension control method based on tension coupling relationship according to claim 1, characterized in that: The adjustment of the roller angular velocity in S6 needs to take into account the coupling relationship between the current span and the adjacent span, and the adjustment formula is: Where K p , K i , K d is the PID control parameter, which is calibrated through experiments.

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