A method and system for adaptive temperature control of hot stamping stickers

Abstract

This invention relates to the field of temperature control technology, specifically disclosing a method and system for adaptive temperature control of hot stamping stickers, comprising the following steps: Step S1: Analyze the geometric characteristics of the hot stamping pattern and estimate the heat capacity distribution, thereby dividing the surface of the hot stamping plate into a thermal inertia region and a thermally sensitive region, and establishing a thermal interference relationship model describing the mutual heat interference between these two regions; Step S2: During the hot stamping process, monitor the hot stamping speed and hot stamping pressure in real time; set a dynamic temperature target value for the thermally sensitive region; based on the thermal interference model, simultaneously generate two instructions: a second heating instruction to drive the thermally sensitive region to the target temperature, and a first heating instruction acting on the thermal inertia region, which contains a compensation amount to offset the temperature change effect of the thermally sensitive region; Step S3: Execute these two heating instructions synchronously, thereby coordinating the heating of the thermal inertia region and the thermally sensitive region of the hot stamping plate to achieve precise and dynamic temperature control.

Description

Technical Field

[0001] This invention relates to the field of temperature control technology, specifically to a method and system for adaptive temperature control of hot stamping stickers. Background Technology

[0002] In the field of hot stamping sticker printing, with the continuous improvement of product appearance quality and performance requirements, traditional hot stamping temperature control methods have gradually exposed many serious problems and are difficult to meet the needs of modern production.

[0003] During large-area hot stamping operations, the limitations of the hot stamping die's structure and heating method result in extremely uneven surface temperature distribution, with temperature differences reaching 3-5℃. This uneven temperature directly leads to distortion at the edges of the pattern, causing the originally fine and accurate outlines to become blurred and distorted, severely affecting the overall clarity and aesthetics of the hot stamped design. Furthermore, temperature differences in different areas also cause inconsistent hot stamping adhesion, resulting in insufficient bonding between the hot stamping layer and the substrate in some areas. This can easily lead to problems such as the hot stamping layer peeling off and flaking during use, significantly reducing the product's quality and durability.

[0004] The presence of heat shadow zones in traditional heating methods exacerbates these problems. These heat shadow zones hinder heat transfer, preventing the area from reaching the same temperature as other areas, resulting in inconsistent hot stamping results. Furthermore, existing temperature control methods largely lack real-time accuracy and cannot adjust the temperature promptly according to dynamic changes during the hot stamping process, thus failing to effectively solve a series of quality issues caused by uneven temperature. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for adaptive temperature control of hot stamping stickers, thereby solving the above-mentioned technical problems.

[0006] The objective of this invention can be achieved through the following technical solutions: A method for adaptive temperature control of hot stamping stickers includes the following steps: Step S1: Obtain the geometric features and estimated heat capacity distribution of the hot stamping pattern on the hot stamping plate. Based on the geometric features and estimated heat capacity distribution, divide the surface of the hot stamping plate into thermal inertia region and thermal sensitive region, and establish a thermal interference relationship model between the thermal inertia region and the thermal sensitive region. Step S2: During the hot stamping period, the hot stamping speed and hot stamping pressure are collected in real time. Based on the hot stamping speed and hot stamping pressure, the target temperature value of the heat-sensitive area is set. Based on the thermal interference relationship model, a second heating command is generated to drive the heat-sensitive area to reach the target temperature value, and a first heating command is generated to act on the thermal inertia area. The first heating command includes the compensation amount of the thermal inertia area. Step S3: Execute the first heating command and the second heating command in real time to simultaneously heat the thermal inertia area and the heat-sensitive area of ​​the hot stamping plate.

[0007] As a further aspect of the present invention: the process of obtaining the geometric features of the hot stamping pattern on the hot stamping plate includes: The original geometric data of the hot stamping pattern is obtained based on the design file. The breaks and burrs of the original geometric data are repaired. The original geometric data is divided into several independent geometric units, and the geometric features of each geometric unit are extracted. The geometric features include edge curvature, actual area, continuity, aperture distribution density, and contour length.

[0008] As a further aspect of the present invention: the process of obtaining the estimated heat capacity distribution of the hot stamping pattern on the hot stamping plate includes: Obtain the substrate of the hot stamping plate, as well as the specific heat capacity and density of the surface coating of the hot stamping plate, and obtain the average thickness of the hot stamping plate based on actual measurements; for any geometric unit, obtain the heat capacity value of the geometric unit C=Vρc, where V is the volume of the geometric unit, ρ is the density of the surface coating, and c is the specific heat capacity of the surface coating. A three-dimensional model of the hot stamping plate is established, and a three-dimensional coordinate system is established on the three-dimensional model. The three-dimensional coordinates of each geometric unit are obtained in the three-dimensional coordinate system, and the heat capacity value of each geometric unit is associated with its three-dimensional coordinates to obtain the estimated heat capacity distribution of the hot stamping plate.

[0009] As a further aspect of the present invention: the process of dividing the surface of the hot stamping plate into a thermally inertial region and a thermally sensitive region includes: A geometric feature threshold and a heat capacity distribution threshold are set. The geometric feature threshold includes a line density threshold Dth, an edge complexity threshold Eth, and a hollowing rate threshold Lth. The heat capacity distribution threshold includes a heat capacity value threshold Cth. Based on the geometric feature threshold and the heat capacity distribution threshold, all geometric units are divided into a thermal inertia region candidate set and a thermal sensitive region candidate set. Conflict determination is performed on the thermal inertia region candidate set and the thermal sensitive region candidate set to finally obtain the thermal inertia region and the thermal sensitive region.

[0010] As a further aspect of the present invention, the process of establishing a thermal interference relationship model between the thermally inertial region and the thermally sensitive region includes: Based on the principle of thermal balance, a mathematical coupling model is constructed to determine the thermal interference relationship between the thermal inertia region and the thermally sensitive region. The input parameters of this mathematical coupling model are defined, including the thermal characteristic parameters of the thermal inertia region and the thermally sensitive region, real-time temperature, real-time process parameters, and the instantaneous target temperature value of the thermally sensitive region. The output parameters of the mathematical coupling model are also defined, namely the target heating amount for the thermally sensitive region and the thermal interference compensation amount for the thermal inertia region. A core expression is established, which includes the target heating amount for the thermally sensitive region Q2 = C2 × (T2). target -T2)+k1×S×(T1-T2)×(1-v / v0)+k2×P, and thermal inertia region thermal interference compensation Q1=k3×S×(T2) target -T2)×(1-v / v0)-C1×(T1-T1 initial ), where C1 and C2 are the average heat capacities of the thermal inertia region and the thermally sensitive region, respectively; S is the contact area between the thermal inertia region and the thermally sensitive region; T1 and T2 are the real-time temperatures of the thermal inertia region and the thermally sensitive region, respectively; T2 target Here, v represents the instantaneous target temperature of the heat-sensitive area, v is the real-time hot stamping speed (the relative movement distance between the substrate and the hot stamping plate per unit time), v0 is the preset baseline hot stamping speed, and T1 is the hot stamping speed. initial K is the initial steady-state temperature of the thermal inertia region, and k1, k2, and k3 are correction coefficients of the mathematical coupling model. By conducting hot stamping experiments with controlled variables, temperature change data of thermal inertia and thermally sensitive areas under different process conditions were collected. Based on the experimental data, a fitting algorithm was used to solve for the values ​​of correction coefficients k1, k2, and k3 of the thermal interference relationship model, so that the error between the output value of the mathematical coupling model and the experimental measurement value is minimized, and the thermal interference relationship model is finally obtained.

[0011] As a further aspect of the present invention: the process of setting the target temperature value of the heat-sensitive area includes: Different types of heat-sensitive areas and different types of substrates are selected, and these heat-sensitive areas and substrates are randomly combined. A reference hot stamping speed and a reference hot stamping pressure are set, and the base temperature value under the reference hot stamping speed and reference hot stamping pressure is determined through experiments. Based on the base temperature value, a hot stamping speed-temperature correlation model and a hot stamping pressure-temperature correction model are established respectively. The hot stamping speed-temperature correlation model is used to obtain the temperature adjustment amount Tv=kv×(v-v0) caused by the change of hot stamping speed, and the hot stamping pressure-temperature correction model is used to obtain the temperature correction amount Tp=kp×(P-P0) caused by the change of hot stamping pressure, where v is the real-time hot stamping speed, P is the real-time hot stamping pressure, v0 and P0 are the reference hot stamping speed and reference hot stamping pressure, respectively, and kv and kp are the speed temperature coefficient and pressure temperature coefficient obtained through experimental fitting, respectively. The process involves obtaining the heat-sensitive area of ​​the hot stamping stencil to be printed, and retrieving the base temperature value, speed temperature coefficient, and pressure temperature coefficient based on the type and substrate of the stencil. It also involves obtaining the current hot stamping speed and pressure for the heat-sensitive area, denoted as the current hot stamping speed and current hot stamping pressure, respectively. Finally, the target temperature value T2 for the current heat-sensitive area is obtained. target =T0+kv×(v´-v0)+kp××(P´-P0), where T0 is the base temperature value, v´ is the current hot stamping speed, and P´ is the current hot stamping pressure; The process of determining the base temperature value includes selecting the optimal temperature range for each combination based on the qualified criteria of edge distortion less than or equal to 0.05 mm and adhesion less than or equal to 95%, and obtaining the median of the optimal temperature range as the base temperature value.

[0012] As a further aspect of the present invention: the process of generating the second heating command includes: Obtain the average heat capacity C2 of the heat-sensitive area and the real-time temperature T2 of the heat-sensitive area. time And obtain the real-time temperature T1 of the thermal inertia region. time Real-time hot stamping speed v time and real-time hot stamping pressure P time The contact area S between the heat-sensitive region and the thermal inertia region time Based on the aforementioned thermal interference relationship model, the total target heating amount Q2 required for the thermally sensitive area is obtained. time =C2×(T2 target -T2)+k1×S×(T1 time -T2 time )×(1-v time / v0)+k2×P timeThe total target heating amount is converted into control parameters for the heating element, including heating power value and heating duration, and a second heating command is generated that can be executed by the heating element.

[0013] As a further aspect of the present invention: the generation process of the first heating command includes: Obtain the average heat capacity C1 of the thermal inertia region, and according to the thermal interference relationship model, obtain the compensation amount Q1´=k3×S×(T2) target -T2)×(1-v time / v0)-C1×(T1 time -T1 initial And obtain the basic heating amount Q1 of the thermal inertia region. base =C1×(T1 target -T1), where T1 target Let the preset base temperature be the temperature of the thermal inertia region; then the total heat required for the thermal inertia region is obtained as Q1 = Q1' + Q1'. base The total heat required in the thermal inertia region is converted into new control parameters for the heating element, generating a first heating command that can be executed by the heating element.

[0014] A hot stamping sticker temperature adaptive control system includes: Region modeling module: Obtain the geometric features and estimated heat capacity distribution of the hot stamping pattern on the hot stamping plate. Based on the geometric features and estimated heat capacity distribution, divide the surface of the hot stamping plate into thermal inertia region and thermal sensitive region, and establish a thermal interference relationship model between thermal inertia region and thermal sensitive region. Dynamic control module: During the hot stamping period, the hot stamping speed and hot stamping pressure are collected in real time. Based on the hot stamping speed and hot stamping pressure, the target temperature value of the heat-sensitive area is set. Based on the thermal interference relationship model, a second heating command is generated to drive the heat-sensitive area to reach the target temperature value, and a first heating command is generated to act on the thermal inertia area. The first heating command includes the compensation amount of the thermal inertia area. Execution module: Executes the first heating command and the second heating command in real time, and simultaneously heats the thermal inertia area and the heat-sensitive area of ​​the hot stamping plate.

[0015] The beneficial effects of this invention are as follows: This invention achieves proactive prediction and dynamic compensation of heat transfer between regions by finely dividing the hot stamping plate and establishing a coupled thermal interference model. This solves the problem of uneven temperature caused by differences in thermal characteristics, significantly improving the overall clarity and edge precision of the hot stamping pattern. Furthermore, this invention can sense changes in hot stamping speed and pressure in real time and dynamically adjust the instantaneous temperature target value of the heat-sensitive area, synchronously generating heating instructions containing compensation. This allows temperature control to adapt to the production rhythm, effectively overcoming the shortcomings of traditional temperature control that is lagging and rigid. It ensures consistent adhesion under process fluctuations and greatly reduces quality defects such as poor hot stamping and peeling. Attached Figure Description

[0016] The invention will now be further described with reference to the accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the steps of a hot stamping sticker temperature adaptive control method and system according to the present invention. Detailed Implementation

[0018] 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.

[0019] Please see Figure 1 As shown, this invention is a method for adaptive temperature control of hot stamping stickers, comprising the following steps: Step S1: Obtain the geometric features and estimated heat capacity distribution of the hot stamping pattern on the hot stamping plate. Based on the geometric features and estimated heat capacity distribution, divide the surface of the hot stamping plate into thermal inertia region and thermal sensitive region, and establish a thermal interference relationship model between the thermal inertia region and the thermal sensitive region.

[0020] In a preferred embodiment of the present invention, the process of obtaining the geometric features of the hot stamping pattern on the hot stamping plate includes: The original geometric data of the hot stamping pattern is obtained based on the design file. The breaks and burrs of the original geometric data are repaired. The original geometric data is divided into several independent geometric units, and the geometric features of each geometric unit are extracted. The geometric features include edge curvature, actual area, continuity, aperture distribution density, and contour length.

[0021] Specifically, the original geometric data of the hot stamping pattern is obtained by prioritizing vector design files containing precise contour coordinates. When vector files are unavailable, the data is obtained through high-precision scanning and vectorization, and all data is converted to a unified format under a standard coordinate system. The data is preprocessed to remove redundant information unrelated to the geometric shape and to repair breakpoints and burrs in the contour, dividing the pattern into independent geometric units. For each preprocessed geometric unit, core geometric features related to thermal properties are extracted, including: calculating the actual area of ​​each geometric unit and determining its continuity; extracting the feature width and edge curvature of the line structure; extracting the aperture and distribution density of the hollow structure; and extracting the total length and complexity of the edge contour.

[0022] In a preferred embodiment of the present invention, the process of obtaining the estimated heat capacity distribution of the hot stamping pattern on the hot stamping plate includes: Obtain the substrate of the hot stamping plate, as well as the specific heat capacity and density of the surface coating of the hot stamping plate, and obtain the average thickness of the hot stamping plate based on actual measurements; for any geometric unit, obtain the heat capacity value of the geometric unit C=Vρc, where V is the volume of the geometric unit, ρ is the density of the surface coating, and c is the specific heat capacity of the surface coating. A three-dimensional model of the hot stamping plate is established, and a three-dimensional coordinate system is established on the three-dimensional model. The three-dimensional coordinates of each geometric unit are obtained in the three-dimensional coordinate system, and the heat capacity value of each geometric unit is associated with its three-dimensional coordinates to obtain the estimated heat capacity distribution of the hot stamping plate.

[0023] It is worth noting that for units with a hollow structure, the unit volume (V) is calculated based on the geometric area, effective solid thickness and hollow ratio; for fine line units, the calculated heat capacity is multiplied by a heat dissipation correction factor less than 1.

[0024] In a preferred embodiment of the present invention, the process of dividing the surface of the hot stamping plate into a thermal inertia region and a heat-sensitive region includes: Set geometric feature thresholds and thermal capacity distribution thresholds. The geometric feature thresholds include line density threshold Dth, edge complexity threshold Eth, and hollowness threshold Lth. The thermal capacity distribution thresholds include thermal capacity value threshold Cth. Based on the geometric feature thresholds and thermal capacity distribution thresholds, divide all geometric units into a thermal inertia region candidate set and a thermal sensitive region candidate set, and determine the conflict between the thermal inertia region candidate set and the thermal sensitive region candidate set.

[0025] The process of dividing all geometric units into candidate sets of thermally inertial regions and candidate sets of thermally sensitive regions includes: Iterate through all geometric units. For any geometric unit, obtain its line density D, edge complexity E, and hollowness ratio L. If the geometric unit satisfies... Then, the geometric unit is denoted as the thermally sensitive candidate unit; the thermally sensitive candidate unit constitutes the thermally sensitive region candidate set. Traverse all geometric elements. For any geometric element, obtain the heat capacity value C of the geometric element. If the heat capacity value C of the geometric element is greater than or equal to Cth, then the geometric element is a candidate element for thermal inertia. The candidate set of thermal inertia regions is formed by all the candidate elements for thermal inertia.

[0026] The process of conflict determination for the candidate set of thermal inertial regions and the candidate set of thermally sensitive regions includes: Thermally sensitive regions have higher priority than thermally inertial regions. If a geometric element belongs to both the thermally inertial region candidate set and the thermally sensitive region candidate set, then the geometric element is preferentially classified as a thermally sensitive region.

[0027] It is worth noting that the dense lines, complex edges, and hollowed-out features of the geometric units in this type of area are the core causes of hot stamping quality problems, so precise temperature control should be prioritized.

[0028] The process of setting the geometric feature threshold and the heat capacity distribution threshold includes: The line density of the geometric unit is the ratio of the total length of the lines within the geometric unit to the total area of ​​the geometric unit; the edge complexity of the geometric unit is the maximum edge curvature of the edge lines of the geometric unit; and the hollowing rate of the geometric unit is the ratio of the hollowing area of ​​the geometric unit to the total area of ​​the geometric unit. Define the qualified standards for hot stamping quality as the process target, and fix the core parameters of the substrate, gold foil type and hot stamping equipment used for testing; call up the established geometric feature database containing a variety of typical patterns and the estimated heat capacity distribution database; Multiple sets of pattern samples with different line densities were selected from the geometric feature database for hot stamping tests. By analyzing the relationship between the edge distortion degree of the hot stamped pattern and the line density, the maximum line density value corresponding to the edge distortion degree meeting the qualified standard was determined as the line density threshold. Hot stamping tests were conducted on samples with different edge curvatures, and the edge curvature threshold was determined based on the edge clarity. Multiple sets of pattern samples with different cutout ratios were made for heat transfer and hot stamping tests. By analyzing the relationship between the cutout ratio and surface temperature uniformity and adhesion, the cutout ratio corresponding to the temperature fluctuation and adhesion non-uniformity reaching the preset critical conditions was determined as the cutout ratio threshold. The heat capacity distribution of all geometric units is statistically analyzed from the estimated heat capacity distribution database; the heat capacity value is correlated with the stability of the hot stamping temperature, and a heat capacity value quantile is set based on the statistical analysis results. The heat capacity value corresponding to the quantile is initially set as the heat capacity value threshold; the typical pattern is divided and hot stamping is verified using the initial threshold, and the proportion of the quantile is calibrated according to the verification results to obtain the final heat capacity value threshold.

[0029] In a preferred embodiment of the present invention, the process of establishing a thermal interference relationship model between the thermal inertia region and the thermally sensitive region includes: Based on the principle of thermal balance, a mathematical coupling model is constructed to determine the thermal interference relationship between the thermal inertia region and the thermally sensitive region. The input parameters of this mathematical coupling model are defined, including the thermal characteristic parameters of the thermal inertia region and the thermally sensitive region, real-time temperature, real-time process parameters, and the instantaneous target temperature value of the thermally sensitive region. The output parameters of the mathematical coupling model are also defined, namely the target heating amount for the thermally sensitive region and the thermal interference compensation amount for the thermal inertia region. A core expression is established, which includes the target heating amount for the thermally sensitive region Q2 = C2 × (T2). target -T2)+k1×S×(T1-T2)×(1-v / v0)+k2×P, and thermal inertia region thermal interference compensation Q1=k3×S×(T2) target -T2)×(1-v / v0)-C1×(T1-T1 initial ), where C1 and C2 are the average heat capacities of the thermal inertia region and the thermally sensitive region, respectively; S is the contact area between the thermal inertia region and the thermally sensitive region; T1 and T2 are the real-time temperatures of the thermal inertia region and the thermally sensitive region, respectively; T2 target Here, v represents the instantaneous target temperature of the heat-sensitive area, v is the real-time hot stamping speed (the relative movement distance between the substrate and the hot stamping plate per unit time), v0 is the preset baseline hot stamping speed, and T1 is the hot stamping speed. initial K is the initial steady-state temperature of the thermal inertia region. K1, K2, and K3 are correction coefficients of the mathematical coupling model, and the optimal values ​​are obtained by fitting the experimental data using the least squares method. By conducting hot stamping experiments with controlled variables, temperature change data of thermal inertia and thermally sensitive areas under different process conditions were collected. Based on the experimental data, a fitting algorithm was used to solve for the values ​​of correction coefficients k1, k2, and k3 of the thermal interference relationship model, so that the error between the output value of the mathematical coupling model and the experimental measurement value is minimized, and the thermal interference relationship model is finally obtained.

[0030] Step S2: During the hot stamping period, the hot stamping speed and hot stamping pressure are collected in real time. Based on the hot stamping speed and hot stamping pressure, the target temperature value of the heat-sensitive area is set. Based on the thermal interference relationship model, a second heating command is generated to drive the heat-sensitive area to reach the target temperature value, and a first heating command is generated to act on the thermal inertia area. The first heating command includes the compensation amount of the thermal inertia area.

[0031] In a preferred embodiment of the present invention, the process of determining the hot stamping time period includes: The moment when the hot stamping plate comes into contact with the substrate is recorded as the contact moment, and the moment when the hot stamping plate separates from the substrate is recorded as the separation moment. The time period consisting of the contact moment and the separation moment is recorded as the hot stamping time period.

[0032] In a preferred embodiment of the present invention, the process of setting the target temperature value of the heat-sensitive area includes: Different types of heat-sensitive areas and different types of substrates are selected, and these heat-sensitive areas and substrates are randomly combined. A reference hot stamping speed and a reference hot stamping pressure are set, and the base temperature value under the reference hot stamping speed and reference hot stamping pressure is determined through experiments. Based on the base temperature value, a hot stamping speed-temperature correlation model and a hot stamping pressure-temperature correction model are established respectively. The hot stamping speed-temperature correlation model is used to obtain the temperature adjustment amount Tv=kv×(v-v0) caused by the change of hot stamping speed, and the hot stamping pressure-temperature correction model is used to obtain the temperature correction amount Tp=kp×(P-P0) caused by the change of hot stamping pressure, where v is the real-time hot stamping speed, P is the real-time hot stamping pressure, v0 and P0 are the reference hot stamping speed and reference hot stamping pressure, respectively, and kv and kp are the speed temperature coefficient and pressure temperature coefficient obtained through experimental fitting, respectively. The process involves obtaining the heat-sensitive area of ​​the hot stamping stencil to be printed, and retrieving the base temperature value, speed temperature coefficient, and pressure temperature coefficient based on the type and substrate of the stencil. It also involves obtaining the current hot stamping speed and pressure for the heat-sensitive area, denoted as the current hot stamping speed and current hot stamping pressure, respectively. Finally, the target temperature value T2 for the current heat-sensitive area is obtained. target =T0+kv×(v´-v0)+kp××(P´-P0), where T0 is the base temperature value, v´ is the current hot stamping speed, and P´ is the current hot stamping pressure; The process of determining the base temperature value includes selecting the optimal temperature range for each combination based on the qualified criteria of edge distortion less than or equal to 0.05 mm and adhesion less than or equal to 95%, and obtaining the median of the optimal temperature range as the base temperature value.

[0033] It is worth noting that if the hot stamping speed and hot stamping pressure deviate from the reference hot stamping speed and reference hot stamping pressure at the same time, and in opposite directions, such as v > v0 and P > P0, then after fusion, a coupling correction coefficient of 0.98 is applied to avoid overcompensation; if the directions are the same, such as v > v0 and P < P0, then a coupling correction coefficient of 1.02 is applied to enhance the compensation effect.

[0034] In a preferred embodiment of the present invention, the process of generating the second heating command includes: Obtain the average heat capacity C2 of the heat-sensitive area and the real-time temperature T2 of the heat-sensitive area. time And obtain the real-time temperature T1 of the thermal inertia region. time Real-time hot stamping speed v time and real-time hot stamping pressure P time The contact area S between the heat-sensitive region and the thermal inertia region time Based on the aforementioned thermal interference relationship model, the total target heating amount Q2 required for the thermally sensitive area is obtained. time =C2×(T2 target -T2)+k1×S×(T1 time -T2 time )×(1-v time / v0)+k2×P time The total target heating amount is converted into control parameters for the heating element, including heating power value and heating duration, and a second heating command is generated that can be executed by the heating element.

[0035] Specifically, the meaning and source of each parameter in the calculation process of the total target heating amount required for the heat-sensitive area have been clarified in the previous steps, and the calculation process is completed through the built-in algorithm of the temperature control system; C2×(T2) target -T2) represents the basic heating amount required to raise the temperature of the heat-sensitive area from the current temperature to the target temperature, ensuring core temperature control requirements; k1×S×(T1) time -T2 time )×(1-v time / v0) is the thermal interference compensation amount from the thermal inertia region to the thermally sensitive region. If T1 > T2, this value is positive, supplementing the heat conducted by the inertia region; if T1 < T2, this value is negative, offsetting the heat loss from the sensitive region to the inertia region; k2×P time This is a pressure correction value. Higher pressure results in higher heat transfer efficiency. This value is experimentally fitted to ensure the heating amount matches the contact tightness. If Q2 < 0, it indicates the current temperature is higher than the target value, so Q2 is temporarily output as 0, i.e., heating stops. If Q2 > Q2... max Q2 max If the rated maximum heating capacity of the heating element in the heat-sensitive area is Q2 = Q2 max This triggers a system alert.

[0036] In a preferred embodiment of the present invention, the process of generating the first heating command includes: Obtain the average heat capacity C1 of the thermal inertia region, and according to the thermal interference relationship model, obtain the compensation amount Q1´=k3×S×(T2) target -T2)×(1-v time / v0)-C1×(T1 time -T1 initial And obtain the basic heating amount Q1 of the thermal inertia region. base =C1×(T1 target -T1), where T1 target Let the preset base temperature be the temperature of the thermal inertia region; then the total heat required for the thermal inertia region is obtained as Q1 = Q1' + Q1'. base The total heat required in the thermal inertia region is converted into new control parameters for the heating element, generating a first heating command that can be executed by the heating element.

[0037] Specifically, k3×S×(T2) target -T2)×(1-v time / v0) is the core compensation term, quantifying the thermal interference of heating or cooling in the thermally sensitive area on the thermally inertial area; if T2 target If T2 > T2, then the heat-sensitive area needs to be heated and absorb heat from the thermal inertia region; if T2 target If T2 < T2, then the heat-sensitive area needs to be cooled to offset the excess heat transferred from the heat-sensitive area to the thermal inertia area; -C1×(T1) time -T1 initial This is a self-temperature correction term. If the current temperature T1 of the thermal inertia region is lower than the initial stable temperature T1, then... initial If additional heat is required, then T1 should be added; if T1 is higher than the initial stable temperature T1 initial This reduces the amount of heating and maintains a stable base temperature in the inertial zone.

[0038] It is worth noting that the preset base temperature T1 of the thermal inertia region target Through process experimentation and calibration, the temperature is adapted to the base temperature T0 of the heat-sensitive area to ensure temperature coordination between areas.

[0039] Step S3: Execute the first heating command and the second heating command in real time to simultaneously heat the thermal inertia area and the heat-sensitive area of ​​the hot stamping plate.

[0040] In a preferred embodiment of the present invention, the process of executing the first heating command and the second heating command includes: The system receives the first heating command and the second heating command in real time, and binds the control parameters and the new control parameters to the independent heating elements corresponding to the thermal inertia region and the thermal sensitive region, respectively. It also generates a pulse width modulation signal to drive each independent heating element, and adjusts the current duty cycle output to each independent heating element in real time based on the pulse width modulation signal.

[0041] It is worth noting that the start times of the first heating control command and the second heating control command are coordinated to ensure that the heating actions of the thermal inertia area and the thermally sensitive area are started synchronously, and the deviation of the start time of the two is controlled within a preset threshold, which is less than or equal to 0.01s.

[0042] A hot stamping sticker temperature adaptive control system includes: Region modeling module: Obtain the geometric features and estimated heat capacity distribution of the hot stamping pattern on the hot stamping plate. Based on the geometric features and estimated heat capacity distribution, divide the surface of the hot stamping plate into thermal inertia region and thermal sensitive region, and establish a thermal interference relationship model between thermal inertia region and thermal sensitive region. Dynamic control module: During the hot stamping period, the hot stamping speed and hot stamping pressure are collected in real time. Based on the hot stamping speed and hot stamping pressure, the target temperature value of the heat-sensitive area is set. Based on the thermal interference relationship model, a second heating command is generated to drive the heat-sensitive area to reach the target temperature value, and a first heating command is generated to act on the thermal inertia area. The first heating command includes the compensation amount of the thermal inertia area. Execution module: Executes the first heating command and the second heating command in real time, and simultaneously heats the thermal inertia area and the heat-sensitive area of ​​the hot stamping plate.

[0043] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A method for adaptive temperature control of hot stamping stickers, characterized in that, Includes the following steps: Step S1: Obtain the geometric features and estimated heat capacity distribution of the hot stamping pattern on the hot stamping plate. Based on the geometric features and estimated heat capacity distribution, divide the surface of the hot stamping plate into thermal inertia region and thermal sensitive region, and establish a thermal interference relationship model between the thermal inertia region and the thermal sensitive region. Step S2: During the hot stamping time period, the hot stamping speed and hot stamping pressure are collected in real time, and the target temperature value of the heat-sensitive area is set according to the hot stamping speed and hot stamping pressure. Based on the thermal interference relationship model, a second heating command is generated to drive the thermally sensitive area to reach the target temperature value, and a first heating command is generated to act on the thermal inertia area, wherein the first heating command includes a compensation amount for the thermal inertia area. Step S3: Execute the first heating command and the second heating command in real time to simultaneously heat the thermal inertia area and the heat-sensitive area of ​​the hot stamping plate.

2. The method for adaptive temperature control of hot stamping stickers according to claim 1, characterized in that, In step S1, the process of obtaining the geometric features of the hot stamping pattern on the hot stamping plate includes: The original geometric data of the hot stamping pattern is obtained based on the design file. The breaks and burrs of the original geometric data are repaired. The original geometric data is divided into several independent geometric units, and the geometric features of each geometric unit are extracted. The geometric features include edge curvature, actual area, continuity, aperture distribution density, and contour length.

3. The method for adaptive temperature control of hot stamping stickers according to claim 1, characterized in that, In step S1, the process of obtaining the estimated heat capacity distribution of the hot stamping pattern on the hot stamping plate includes: Obtain the substrate of the hot stamping plate, as well as the specific heat capacity and density of the surface coating of the hot stamping plate, and obtain the average thickness of the hot stamping plate based on actual measurements; for any geometric unit, obtain the heat capacity value of the geometric unit C=Vρc, where V is the volume of the geometric unit, ρ is the density of the surface coating, and c is the specific heat capacity of the surface coating. A three-dimensional model of the hot stamping plate is established, and a three-dimensional coordinate system is established on the three-dimensional model. The three-dimensional coordinates of each geometric unit are obtained in the three-dimensional coordinate system, and the heat capacity value of each geometric unit is associated with its three-dimensional coordinates to obtain the estimated heat capacity distribution of the hot stamping plate.

4. The method for adaptive temperature control of hot stamping stickers according to claim 1, characterized in that, In step S1, the process of dividing the surface of the hot stamping plate into thermally inertial regions and thermally sensitive regions includes: A geometric feature threshold and a heat capacity distribution threshold are set. The geometric feature threshold includes a line density threshold Dth, an edge complexity threshold Eth, and a hollowing rate threshold Lth. The heat capacity distribution threshold includes a heat capacity value threshold Cth. Based on the geometric feature threshold and the heat capacity distribution threshold, all geometric units are divided into a thermal inertia region candidate set and a thermal sensitive region candidate set. Conflict determination is performed on the thermal inertia region candidate set and the thermal sensitive region candidate set to finally obtain the thermal inertia region and the thermal sensitive region.

5. The method for adaptive temperature control of hot stamping stickers according to claim 1, characterized in that, In step S1, the process of establishing a thermal interference relationship model between the thermal inertial region and the thermally sensitive region includes: Based on the principle of thermal balance, a mathematical coupling model is constructed to determine the thermal interference relationship between the thermal inertia region and the thermally sensitive region. The input parameters of this mathematical coupling model are defined, including the thermal characteristic parameters of the thermal inertia region and the thermally sensitive region, real-time temperature, real-time process parameters, and the instantaneous target temperature value of the thermally sensitive region. The output parameters of the mathematical coupling model are also defined, namely the target heating amount for the thermally sensitive region and the thermal interference compensation amount for the thermal inertia region. A core expression is established, which includes the target heating amount for the thermally sensitive region Q2 = C2 × (T2). target -T2)+k1×S×(T1-T2)×(1-v / v0)+k2×P, and thermal inertia region thermal interference compensation Q1=k3×S×(T2) target -T2)×(1-v / v0)-C1×(T1-T1 initial ), where C1 and C2 are the average heat capacities of the thermal inertia region and the thermally sensitive region, respectively; S is the contact area between the thermal inertia region and the thermally sensitive region; T1 and T2 are the real-time temperatures of the thermal inertia region and the thermally sensitive region, respectively; T2 target Here, v represents the instantaneous target temperature of the heat-sensitive area, v is the real-time hot stamping speed (the relative movement distance between the substrate and the hot stamping plate per unit time), v0 is the preset baseline hot stamping speed, and T1 is the hot stamping speed. initial K is the initial steady-state temperature of the thermal inertia region, and k1, k2, and k3 are correction coefficients of the mathematical coupling model. By conducting hot stamping experiments with controlled variables, temperature change data of thermal inertia and thermally sensitive areas under different process conditions were collected. Based on the experimental data, a fitting algorithm was used to solve for the values ​​of correction coefficients k1, k2, and k3 of the thermal interference relationship model, so that the error between the output value of the mathematical coupling model and the experimental measurement value is minimized, and the thermal interference relationship model is finally obtained.

6. The method for adaptive temperature control of hot stamping stickers according to claim 1, characterized in that, In step S2, the process of setting the target temperature value for the heat-sensitive area includes: Different types of heat-sensitive areas and different types of substrates are selected, and these heat-sensitive areas and substrates are randomly combined. A reference hot stamping speed and a reference hot stamping pressure are set, and the base temperature value under the reference hot stamping speed and reference hot stamping pressure is determined through experiments. Based on the base temperature value, a hot stamping speed-temperature correlation model and a hot stamping pressure-temperature correction model are established respectively. The hot stamping speed-temperature correlation model is used to obtain the temperature adjustment amount Tv=kv×(v-v0) caused by the change of hot stamping speed, and the hot stamping pressure-temperature correction model is used to obtain the temperature correction amount Tp=kp×(P-P0) caused by the change of hot stamping pressure, where v is the real-time hot stamping speed, P is the real-time hot stamping pressure, v0 and P0 are the reference hot stamping speed and reference hot stamping pressure, respectively, and kv and kp are the speed temperature coefficient and pressure temperature coefficient obtained through experimental fitting, respectively. The process involves obtaining the heat-sensitive area of ​​the hot stamping stencil to be printed, and retrieving the base temperature value, speed temperature coefficient, and pressure temperature coefficient based on the type and substrate of the stencil. It also involves obtaining the current hot stamping speed and pressure for the heat-sensitive area, denoted as the current hot stamping speed and current hot stamping pressure, respectively. Finally, the target temperature value T2 for the current heat-sensitive area is obtained. target =T0+kv×(v´-v0)+kp××(P´-P0), where T0 is the base temperature value, v´ is the current hot stamping speed, and P´ is the current hot stamping pressure; The process of determining the base temperature value includes selecting the optimal temperature range for each combination based on the qualified criteria of edge distortion less than or equal to 0.05 mm and adhesion less than or equal to 95%, and obtaining the median of the optimal temperature range as the base temperature value.

7. The method for adaptive temperature control of hot stamping stickers according to claim 1, characterized in that, In step S2, the process of generating the second heating command includes: Obtain the average heat capacity C2 of the heat-sensitive area and the real-time temperature T2 of the heat-sensitive area. time And obtain the real-time temperature T1 of the thermal inertia region. time Real-time hot stamping speed v time and real-time hot stamping pressure P time The contact area S between the heat-sensitive region and the thermal inertia region time Based on the aforementioned thermal interference relationship model, the total target heating amount Q2 required for the thermally sensitive area is obtained. time =C2×(T2 target -T2)+k1×S×(T1 time -T2 time )×(1-v time / v0)+k2×P time The total target heating amount is converted into control parameters for the heating element, including heating power value and heating duration, and a second heating command is generated that can be executed by the heating element.

8. The method for adaptive temperature control of hot stamping stickers according to claim 1, characterized in that, In step S2, the process of generating the first heating command includes: Obtain the average heat capacity C1 of the thermal inertia region, and according to the thermal interference relationship model, obtain the compensation amount Q1´=k3×S×(T2) target -T2)×(1-v time / v0)-C1×(T1 time -T1 initial And obtain the basic heating amount Q1 of the thermal inertia region. base =C1×(T1 target -T1), where T1 target Let the preset base temperature be the temperature of the thermal inertia region; then the total heat required for the thermal inertia region is obtained as Q1 = Q1' + Q1'. base The total heat required in the thermal inertia region is converted into new control parameters for the heating element, generating a first heating command that can be executed by the heating element.

9. A hot stamping sticker temperature adaptive control system, characterized in that, include: Region modeling module: Obtain the geometric features and estimated heat capacity distribution of the hot stamping pattern on the hot stamping plate. Based on the geometric features and estimated heat capacity distribution, divide the surface of the hot stamping plate into thermal inertia region and thermal sensitive region, and establish a thermal interference relationship model between thermal inertia region and thermal sensitive region. Dynamic control module: During the hot stamping period, the hot stamping speed and pressure are collected in real time, and the target temperature value of the heat-sensitive area is set according to the hot stamping speed and pressure. Based on the thermal interference relationship model, a second heating command is generated to drive the thermally sensitive area to reach the target temperature value, and a first heating command is generated to act on the thermal inertia area, wherein the first heating command includes a compensation amount for the thermal inertia area. Execution module: Executes the first heating command and the second heating command in real time, and simultaneously heats the thermal inertia area and the heat-sensitive area of ​​the hot stamping plate.

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