Temperature control method and system for injection mold processing

Abstract

The present invention discloses a temperature control method and system for injection mold processing, which specifically relates to the technical field of production temperature control, and is used to solve the problems of insufficient accuracy and response speed of temperature control in existing injection mold processing; differential temperature analysis allows the operator to identify and adjust any potential thermal imbalance in the mold before injection, and analyzes the entropy value increase of the molten plastic to help monitor and control the molten state in the barrel; determines whether to allow the molten plastic to be injected from the barrel into the cavity of the mold, and through comprehensive consideration of the heat release of the molten plastic, the efficiency of the cooling system and the influence of the injection speed, achieves precise control of the temperature distribution in the mold, and prevents production problems caused by abnormal temperature. This dynamic temperature monitoring and adjustment mechanism significantly improves product quality and reduces downtime and maintenance costs caused by temperature problems.

Description

Technical Field

[0001] The present invention relates to the technical field of production temperature control, and more specifically, to a temperature control method and system for injection mold processing. Background Art

[0002] Temperature control in injection mold processing is a key technical link to ensure product quality and production efficiency. During the injection molding process, molten plastic must be injected into the mold under strictly controlled temperature conditions to ensure that the plastic can properly fill the mold and solidify during the cooling process to form the desired product shape and size. Temperature control not only affects the appearance quality of the product, but is also directly related to the product's inherent physical properties, such as strength, transparency, and resistance to environmental strain.

[0003] Traditional temperature control methods usually rely on fixed temperature sensors inside the mold and preset heating and cooling cycles. In traditional methods, the control of mold temperature usually cannot respond in real time to the flow characteristics of molten plastic and changes in the external production environment, making temperature management often reactive rather than preventive. There are problems with the accuracy and response speed of temperature control in injection mold processing. Due to the lack of real-time temperature adjustment capabilities, the temperature distribution of the mold is often uneven, resulting in defects such as product shrinkage, warping, or excessive internal stress.

[0004] In order to solve the above problems, a technical solution is now provided. Summary of the invention

[0005] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a temperature control method and system for injection mold processing to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A temperature control method for injection mold processing, comprising the following steps:

[0008] S1: Before the molten plastic is injected into the mold cavity, the temperature differences between different parts of the mold are compared through differential temperature analysis to determine whether the overall thermal balance risk level of the mold is normal;

[0009] S2: Analyze the entropy increment of the molten plastic when it is in the barrel, evaluate the degree of disorder of the plastic melting process in the barrel, and classify the degree of disorder of the plastic melting process in the barrel as abnormal or low risk;

[0010] S3: When the overall thermal balance risk level of the mold is normal and the chaos level of the plastic melting process in the barrel is low risk, the molten plastic is injected from the barrel into the cavity of the mold; otherwise, the temperature operating parameters of the mold cooling system and the barrel heating system are controlled;

[0011] S4: By analyzing the phase changes of heat energy release and cooling energy absorption in the time series, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is evaluated; the change in the speed of the molten plastic injection into the mold is analyzed to evaluate the degree of adverse effects of the injection process on the stability of the temperature distribution in the mold;

[0012] S5: Comprehensively analyze the degree of chaos in the plastic melting process in the barrel, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold, and the degree of adverse impact of the injection process on the stability of the temperature distribution in the mold. Based on the comprehensive analysis results, early warning control of the mold temperature is carried out.

[0013] In a preferred embodiment, the temperature difference between different parts of the mold is compared by differential temperature analysis to determine whether the overall thermal balance risk level of the mold is normal, specifically:

[0014] Collect temperature data of various parts of the mold; perform statistical analysis on the temperature data of all measuring points to find out the temperature of the highest point and the lowest point in the mold, thereby calculating the maximum temperature difference of the mold;

[0015] Set the maximum temperature difference threshold of the mold; when the maximum temperature difference of the mold is greater than the maximum temperature difference threshold of the mold, it is determined that the overall thermal balance potential risk level of the mold is abnormal; when the maximum temperature difference of the mold is less than or equal to the maximum temperature difference threshold of the mold, it is determined that the overall thermal balance potential risk level of the mold is normal.

[0016] In a preferred embodiment, the entropy increment of the molten plastic in the barrel is analyzed to evaluate the degree of disorder of the plastic melting process in the barrel, specifically:

[0017] Calculate the microscopic state number of the barrel heating system, and its expression is: ;in, is the microscopic state number of the barrel heating system, is the base of natural logarithm, is the pressure of the molten plastic in the barrel, is the real-time temperature of the molten plastic at different positions in the barrel, is the volume occupied by the molten plastic, is the Boltzmann constant;

[0018] The entropy increase melting chaos index is calculated by substituting the microscopic state number of the barrel heating system into the entropy increase formula, and its expression is: ;in, is the entropy increase melting chaos index.

[0019] In a preferred embodiment, the degree of disorder in the plastic melting process in the barrel is classified as abnormal or low risk, specifically:

[0020] Compare the entropy increase melting chaos index with the preset entropy increase threshold:

[0021] When the entropy increase melting chaos index is greater than the preset entropy increase threshold, it is determined that the degree of chaos in the plastic melting process in the barrel is abnormal;

[0022] When the entropy increase melting chaos index is less than or equal to the preset entropy increase threshold, it is determined that the chaos level of the plastic melting process in the barrel is low risk.

[0023] In a preferred embodiment, the temperature operating parameters of the mold cooling system and the barrel heating system are controlled, specifically:

[0024] Increase the cooling water flow rate and reduce the cooling water inlet temperature; use temperature sensors to monitor the real-time temperature of each part of the mold, and adjust the opening and closing of the cooling channel through the automatic control system;

[0025] Adjust the power output of the heating belt; when the temperature of the molten plastic is too high or too low, adjust the heating temperature setting of the barrel and the distribution of the heating sections; optimize the heating curve and injection speed of the barrel.

[0026] In a preferred embodiment, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is evaluated by analyzing the phase changes of the heat energy release and the cooling energy absorption in the time series, specifically:

[0027] Collect temperature and pressure data of molten plastic and various parts of the mold in real time;

[0028] Use computational fluid dynamics software to simulate the heat transfer behavior of molten plastic in the mold and the cooling effect of the cooling system;

[0029] Calculate the dynamic synchronization rate of the thermal field, and its expression is: ;in, is the thermal field dynamic synchronization rate, It is The thermal phase of the molten plastic at position, is the cooling phase of the corresponding cooling point, is the total number of measurement points, is the index.

[0030] In a preferred embodiment, the change in the speed of the molten plastic being injected into the mold is analyzed to evaluate the degree of adverse effect of the injection process on the stability of the temperature distribution in the mold, specifically:

[0031] Real-time acquisition of injection speed;

[0032] Setting an injection monitoring interval; obtaining the injection speeds collected within the injection monitoring interval, and numbering the injection speeds collected within the injection monitoring interval;

[0033] The absolute value of the difference between two adjacent injection speeds is calculated, and the absolute value of the difference between all two adjacent injection speeds in the injection monitoring interval is summed and divided by the number of injection speeds collected in the injection monitoring interval to obtain the injection speed abnormality index.

[0034] In a preferred embodiment, the degree of disorder in the plastic melting process in the barrel, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold, and the degree of adverse effect of the injection process on the stability of the temperature distribution in the mold are comprehensively analyzed. According to the comprehensive analysis results, the mold temperature is pre-warned and controlled, specifically:

[0035] The entropy increase melting chaos index, the thermal field dynamic synchronization rate and the injection speed abnormality index are normalized, and the normalized entropy increase melting chaos index, the thermal field dynamic synchronization rate and the injection speed abnormality index are respectively assigned preset proportional coefficients to calculate the injection temperature abnormality warning coefficient;

[0036] Set the injection temperature abnormal warning threshold, and compare the injection temperature abnormal warning coefficient with the injection temperature abnormal warning threshold:

[0037] When the injection temperature abnormal warning coefficient is greater than the injection temperature abnormal warning threshold, it is determined that an injection temperature abnormal signal is generated;

[0038] When the injection temperature abnormal warning coefficient is less than or equal to the injection temperature abnormal warning threshold, it is determined that the injection temperature normal signal is generated;

[0039] When an abnormal injection temperature signal is received, control measures include: immediately checking and adjusting the injection speed, adjusting the cooling system parameters, adjusting the mold temperature, and pausing and checking production.

[0040] On the other hand, the present invention provides a temperature control system for injection mold processing, including a mold balance judgment module, a melt chaos evaluation module, an injection permission judgment module, a synchronization mismatch analysis module, an injection speed abnormality analysis module, and a temperature early warning control module;

[0041] Mold balance judgment module: Before the molten plastic is injected into the mold cavity, the temperature difference between different parts of the mold is compared through differential temperature analysis to determine whether the overall thermal balance risk level of the mold is normal;

[0042] Melting chaos assessment module: Analyze the entropy increase of the molten plastic in the barrel, evaluate the chaos degree of the plastic melting process in the barrel, and classify the chaos degree of the plastic melting process in the barrel as abnormal or low risk;

[0043] Injection permission judgment module: When the overall thermal balance risk level of the mold is normal and the chaos level of the plastic melting process in the barrel is low risk, the molten plastic is injected from the barrel into the cavity of the mold; otherwise, the temperature operating parameters of the mold cooling system and the barrel heating system are controlled;

[0044] Synchronous mismatch analysis module: By analyzing the phase changes of heat energy release and cooling energy absorption in the time series, the thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is evaluated;

[0045] Injection speed abnormality analysis module: analyzes the speed change of molten plastic injected into the mold, and evaluates the adverse effect of the injection process on the temperature distribution stability in the mold;

[0046] Temperature early warning control module: conducts a comprehensive analysis of the degree of disorder in the plastic melting process in the barrel, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold, and the degree of adverse impact of the injection process on the stability of the temperature distribution in the mold. Based on the comprehensive analysis results, early warning control of the mold temperature is performed.

[0047] The technical effects and advantages of the temperature control method and system for injection mold processing of the present invention are as follows:

[0048] 1. Differential temperature analysis allows the operator to identify and adjust any potential thermal imbalance in the mold before injection, thereby preventing product defects such as warping and internal stress caused by uneven temperature. Analyzing the entropy value of molten plastic helps monitor and control the molten state in the barrel, ensuring that the plastic is in the best state before flowing into the mold, reducing uncertainty and variables in the production process. Determining whether to allow the molten plastic to be injected from the barrel into the cavity of the mold ensures that injection is only performed when both the molten plastic and the mold temperature are in an ideal state, maximizing the controllability of the process and the consistency of the product.

[0049] 2. By comprehensively considering the heat release of molten plastic, the efficiency of the cooling system, and the influence of injection speed, precise control of the temperature distribution in the mold can be achieved. Time series phase analysis technology makes temperature control no longer rely solely on static parameters, but can dynamically reflect and adjust temperature changes, thereby more accurately matching the working status of molten plastic and cooling system. Through real-time monitoring and early warning systems, key variables in the production process can be adjusted immediately to prevent production problems caused by abnormal temperatures. This dynamic temperature monitoring and adjustment mechanism significantly improves product quality, reduces downtime and maintenance costs caused by temperature problems, and makes the entire production process more stable and predictable. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A schematic diagram of a temperature control method for injection mold processing according to the present invention;

[0051] Figure 2 The present invention is a schematic structural diagram of a temperature control system for injection mold processing. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] Example 1

[0054] Figure 1 The present invention provides a temperature control method for injection mold processing, which comprises the following steps:

[0055] S1: Before the molten plastic is injected into the mold cavity, the temperature differences between different parts of the mold are compared through differential temperature analysis to determine whether the overall thermal balance risk level of the mold is normal.

[0056] S2: Analyze the entropy increase of the molten plastic while it is in the barrel, evaluate the degree of chaos in the plastic melting process in the barrel, and classify the degree of chaos in the plastic melting process in the barrel as abnormal or low risk.

[0057] S3: When the overall thermal balance risk level of the mold is normal and the risk of chaos in the plastic melting process in the barrel is low, the molten plastic is injected from the barrel into the cavity of the mold; otherwise, the temperature operating parameters of the mold cooling system and the barrel heating system are controlled.

[0058] S4: By analyzing the phase changes of heat energy release and cooling energy absorption in the time series, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is evaluated; the change in the speed of molten plastic injection into the mold is analyzed to evaluate the degree of adverse effect of the injection process on the stability of the temperature distribution in the mold.

[0059] S5: Comprehensively analyze the degree of chaos in the plastic melting process in the barrel, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold, and the degree of adverse impact of the injection process on the stability of the temperature distribution in the mold. Based on the comprehensive analysis results, early warning control of the mold temperature is carried out.

[0060] By comparing the temperature differences between different parts of the mold through differential temperature analysis, it is determined whether the overall thermal balance risk level of the mold is normal, specifically:

[0061] Collect temperature data of various parts of the mold. This is usually achieved through thermocouples or infrared cameras embedded inside the mold. Thermocouples should be evenly distributed in key parts of the mold to capture detailed temperature distribution. The collected data should include the real-time temperature of each measuring point and the exact position of each measuring point in the mold.

[0062] The collected temperature data needs to be analyzed by data processing algorithms. First, statistical analysis is performed on the temperature data of all measurement points to find out and , the purpose is to identify extreme temperature values, which may indicate inadequacies in the mold cooling system or defects in the mold design.

[0063] In differential temperature analysis, it is necessary to determine the key indicators for evaluating the mold temperature distribution. Usually, the key indicators for evaluating the mold temperature distribution include the temperature difference of each part of the mold, the maximum temperature difference of the mold to obtain the temperature difference of each part of the mold, and the maximum temperature difference of the mold is expressed by the following formula: ; is the maximum temperature difference of the mold, It is the temperature at the highest point in the mold. It is the temperature at the lowest point in the mold.

[0064] Set the maximum temperature difference threshold of the mold; when the maximum temperature difference of the mold is greater than the maximum temperature difference threshold of the mold, it is determined that the overall thermal balance potential risk level of the mold is abnormal; when the maximum temperature difference of the mold is less than or equal to the maximum temperature difference threshold of the mold, it is determined that the overall thermal balance potential risk level of the mold is normal.

[0065] The maximum mold temperature difference threshold should be set based on the specific mold design and the material properties used, for example, to 1.1°C.

[0066] The entropy increment of the molten plastic in the barrel is analyzed to evaluate the degree of disorder in the plastic melting process in the barrel, and the degree of disorder in the plastic melting process in the barrel is classified as abnormal or low risk, specifically:

[0067] Calculate the microscopic state number of the barrel heating system, specifically:

[0068] Measuring the temperature and pressure of the molten plastic in the barrel can be obtained by installing high-precision thermocouples and pressure sensors in the barrel:

[0069] Measure the real-time temperature of the molten plastic at different locations in the barrel.

[0070] Measuring the pressure of the molten plastic in the barrel. Pressure changes will also affect the microscopic state and flow characteristics of the molten plastic.

[0071] The calculation of the number of microscopic states of the barrel heating system is the number of microscopic configurations that the barrel heating system may take under given macroscopic conditions. This usually involves complex thermodynamics and statistical physics calculations, which can be achieved through the following formula: ;in, is the microscopic state number of the barrel heating system, is the base of natural logarithm, is the pressure of the molten plastic in the barrel, is the real-time temperature of the molten plastic at different positions in the barrel, is the volume occupied by the molten plastic, is the Boltzmann constant.

[0072] The Boltzmann constant is a fundamental physical constant that relates temperature to energy.

[0073] The entropy increase melting chaos index is calculated by substituting the microscopic state number of the barrel heating system into the entropy increase formula, and its expression is: ;in, is the entropy increase melting chaos index.

[0074] The larger the entropy increase melting chaos index is, the higher the degree of chaos in the plastic melting process in the barrel is.

[0075] The degree of chaos in the plastic melting process in the barrel is classified as abnormal or low risk by comparing the entropy increase melt chaos index with the preset entropy increase threshold:

[0076] When the entropy increase melting chaos index is greater than the preset entropy increase threshold, it is determined that the degree of chaos in the plastic melting process in the barrel is abnormal; this indicates that the flow process of the molten plastic is more chaotic than expected, which may be due to excessive or uneven barrel temperature, improper pressure setting, or quality problems of the raw materials themselves. At this time, measures such as lowering the heating temperature of the barrel, adjusting the distribution of the heating belt, or enhancing the cooling system can be taken. In addition, the pressure and injection speed are adjusted according to the real-time monitoring data to optimize the fluidity of the plastic and reduce entropy increase.

[0077] When the entropy increase melting chaos index is less than or equal to the preset entropy increase threshold, the chaos level of the plastic melting process in the barrel is judged to be low risk; this means that the melting and flow process of the molten plastic in the barrel is relatively stable, the risk is low, and there is no impact temporarily, but it does not mean that there will be no adverse effect on the chaos level of the plastic melting process in the barrel. At this time, maintain the current temperature and pressure settings to keep the operating conditions stable. Regularly check and calibrate the temperature control system and sensors to ensure long-term process stability.

[0078] Among them, the setting of the preset entropy increase threshold is based on the typical behavior of the molten plastic in the barrel and historical data analysis. First, a series of tests are conducted to determine the entropy increase range of the molten plastic under normal operating conditions. In these tests, the entropy increase values ​​under different temperature, pressure and barrel speed conditions are recorded. Then, the data are analyzed to determine the critical value of entropy increase that causes quality problems (such as warping, charring or incomplete filling). The preset entropy increase threshold is usually slightly higher than the maximum entropy increase observed under normal conditions to provide a safety margin to ensure that the process is not mistakenly judged as abnormal even with small operating changes or measurement errors.

[0079] When the overall thermal balance of the mold is normal and the risk of chaos in the plastic melting process in the barrel is low, it means that the temperature and flow state of the molten plastic before injection are in an ideal state and can smoothly fill the mold cavity. In this case, injection helps to ensure the quality of plastic parts, because stable melt flow and good thermal balance are conducive to reducing defects such as internal stress, shrinkage and warping of the product. In addition, stable fluidity also helps to achieve precise molding of complex shapes and ensure the dimensional accuracy and surface finish of injection molded products.

[0080] Therefore, when the overall thermal balance risk level of the mold is normal and the chaos level of the plastic melting process in the barrel is low risk, the molten plastic is injected from the barrel into the cavity of the mold.

[0081] Otherwise, the temperature operating parameters of the mold cooling system and barrel heating system are controlled, specifically:

[0082] First, the mold cooling system can be adjusted to enhance the cooling effect by increasing the cooling water flow and lowering the cooling water inlet temperature, so as to quickly and evenly remove the heat from the mold and prevent product defects caused by local overheating of the mold. In addition, temperature sensors can be used to monitor the real-time temperature of various parts of the mold, and the opening and closing of the cooling channel can be adjusted through the automatic control system to achieve more accurate temperature control.

[0083] For the barrel heating system, the power output of the heating belt should be adjusted according to the real-time monitored plastic temperature and pressure data to ensure that the temperature of the plastic is uniform throughout the barrel. If the temperature of the molten plastic is found to be too high or too low, the heating temperature setting of the barrel and the distribution of the heating section can be appropriately adjusted. In addition, by optimizing the heating curve and injection speed of the barrel, the thermal behavior of the molten plastic can be better controlled to avoid material degradation due to excessive temperature or insufficient filling due to low temperature. This dynamic adjustment strategy helps to maintain the stability of the molten plastic throughout the injection cycle, thereby improving the consistency and quality of the product.

[0084] By analyzing the phase changes of heat energy release and cooling energy absorption in the time series, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is evaluated, specifically:

[0085] In the temperature control of injection mold processing, it is crucial to ensure a high degree of synchronization between the heat of the molten plastic and the cooling system of the mold.

[0086] During the injection molding process, the temperature and pressure data of the molten plastic and various parts of the mold are collected in real time through the high-precision temperature sensors and pressure sensors built into the mold.

[0087] Usually, thermocouples or RTDs (Resistance Temperature Detectors) are installed in key areas of the mold. Thermocouples can provide fast and accurate temperature readings because they are in direct contact with the molten plastic or the mold wall.

[0088] The pressure sensor is installed in the barrel to monitor the pressure of the molten plastic. The change in pressure can reflect the flow characteristics and state of the plastic.

[0089] Use computational fluid dynamics (CFD) software or dedicated thermal analysis tools to simulate the heat transfer behavior of the molten plastic in the mold and the cooling effect of the cooling system.

[0090] By inputting the actual measured temperature, pressure and barrel size parameters, CFD software can simulate the flow and heat transfer of molten plastic in the mold. This simulation helps understand how heat spreads inside the mold and how the cooling system affects the temperature of each part.

[0091] Chaos theory is used to analyze the dynamic phase difference between the heat release of molten plastic and the cooling of the mold. This involves comparing the phase changes of heat energy release and cooling energy absorption over a time series.

[0092] Calculate the dynamic synchronization rate of the thermal field, and its expression is: ;in, is the thermal field dynamic synchronization rate, It is The thermal phase of the molten plastic at position, is the cooling phase of the corresponding cooling point, is the total number of measurement points, is the index, Used to identify specific measuring points in the mold.

[0093] The smaller the thermal field dynamic synchronization rate is, the greater the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is, which may lead to unstable temperature of the plastic in the mold.

[0094] The measuring points can be critical parts of the mold, such as the area near the gate, thick wall parts or other temperature-sensitive areas.

[0095] The thermal phase of molten plastic is usually estimated by the temperature change of the molten plastic at that point. This can be measured by a high-precision temperature sensor installed at a specific position in the mold. The data recorded by the temperature sensor, such as a curve of temperature change over time, can be converted into phase information by subjecting the temperature data to time series analysis, such as Fourier transform, to extract the phase of the main frequency components.

[0096] Similar to the thermal phase, the cooling phase of the cooling point can be measured by temperature sensors installed at the corresponding positions to measure the temperature change of the cooling medium. The phase change can be calculated by thermodynamic models using the inlet and outlet temperature difference of the cooling fluid, combined with the flow rate and other cooling parameters. This usually involves an analysis of the temperature change of the cooling fluid over time, and Fourier transform can also be applied to extract phase information.

[0097] By accurately analyzing the dynamic phase difference between the heat release of the molten plastic and the mold cooling system, this method can significantly improve the temperature control accuracy of injection mold processing. Using chaos theory and advanced CFD simulation technology, it can monitor and optimize the heat propagation in the mold in real time, thereby ensuring that the temperature distribution of the molten plastic in the mold is more uniform and stable. The application of this technology not only reduces product defects caused by uneven temperature, such as warping and stress concentration, but also effectively improves production efficiency and product quality, reduces material waste, and optimizes production costs. In addition, this method provides an efficient temperature monitoring solution for the injection molding process, enhances process control capabilities, and improves product consistency and reliability.

[0098] In the process of injecting molten plastic from the barrel into the mold, high injection speeds can cause the material to fill the mold quickly in a short period of time, which may not allow heat to be evenly distributed, causing local overheating or overcooling. This can lead to uneven temperature distribution, thus affecting the structural integrity and final physical properties of the product. Slower injection speeds may allow heat to be distributed more evenly, but may also cause some parts of the mold to cool prematurely, also affecting temperature uniformity.

[0099] During the injection molding process, the temperature distribution of the molten plastic is affected by many factors, including injection speed, mold temperature, material properties, etc. Among them, the control of injection speed is particularly critical because it directly affects the filling time and heat transfer of the material in the mold.

[0100] The change in the speed of molten plastic injection into the mold is analyzed to evaluate the adverse effect of the injection process on the stability of the temperature distribution in the mold, specifically:

[0101] Collect the injection speed in real time, which is the speed at which the molten plastic is injected from the barrel into the cavity of the mold. This can be achieved by installing a speed sensor on the injection machine, which can measure the flow rate of the plastic from the barrel to the mold. This data should be collected in real time at a high frequency to ensure that all key changes in the injection process are captured.

[0102] Set the injection monitoring interval, which is a real-time monitoring interval, that is, the end point of the injection monitoring interval is always the real-time time point, and the time length of the injection monitoring interval is set according to the actual situation, for example, it can be set to the past 10 seconds or adjusted according to the length of the injection cycle. In this way, the instant changes in speed can be continuously tracked and analyzed in real time.

[0103] The injection speeds collected within the injection monitoring interval are obtained, and the injection speeds collected within the injection monitoring interval are numbered.

[0104] Calculate the absolute value of the difference between two adjacent injection speeds, sum the absolute values ​​of the differences between all two adjacent injection speeds in the injection monitoring interval, and divide it by the number of injection speeds collected in the injection monitoring interval to obtain the injection speed abnormality index, which is marked as .

[0105] The greater the injection speed abnormality index, the greater the adverse effect of the injection process on the stability of the temperature distribution in the mold.

[0106] By implementing this injection speed monitoring and analysis, the stability of the temperature distribution in the mold and the quality of the injection molded product can be significantly improved. By real-time tracking and analyzing the changes in injection speed, abnormal injection behaviors that may cause uneven temperature distribution and defects can be discovered and adjusted in a timely manner.

[0107] Comprehensively analyze the degree of chaos in the plastic melting process in the barrel, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold, and the degree of adverse impact of the injection process on the stability of the temperature distribution in the mold. Based on the comprehensive analysis results, early warning control of the mold temperature is carried out, specifically:

[0108] The entropy increase melting chaos index, thermal field dynamic synchronization rate and injection speed abnormality index are normalized, and after assigning preset proportional coefficients to the normalized entropy increase melting chaos index, thermal field dynamic synchronization rate and injection speed abnormality index respectively, the injection temperature abnormality warning coefficient is calculated.

[0109] The specific implementation method of calculating the injection temperature abnormality warning coefficient is not specifically limited here. Any method that can calculate the injection temperature abnormality warning coefficient by assigning the normalized entropy increase melting chaos index, thermal field dynamic synchronization rate and injection speed abnormality index to preset proportional coefficients respectively is acceptable. In order to implement the technical solution of the present invention, the present invention provides a specific method for calculating the injection temperature abnormality warning coefficient, and its expression is: ;in, is the injection temperature abnormal warning coefficient, are the preset proportional coefficients of the entropy increase melting chaos index, the thermal field dynamic synchronization rate and the injection speed anomaly index, respectively, and Both are greater than 0.

[0110] Because: the larger the entropy increase melting chaos index is, the higher the degree of chaos in the plastic melting process in the barrel is; the smaller the thermal field dynamic synchronization rate is, the greater the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is; the larger the injection speed abnormality index is, the greater the adverse effect of the injection process on the stability of the temperature distribution in the mold is. From the expression of the injection temperature abnormality warning coefficient, it can be seen that the larger the injection temperature abnormality warning coefficient is, the greater the hidden danger of temperature abnormality in the mold during the injection molding process.

[0111] Set the injection temperature abnormal warning threshold, and compare the injection temperature abnormal warning coefficient with the injection temperature abnormal warning threshold:

[0112] When the injection temperature abnormality warning coefficient is greater than the injection temperature abnormality warning threshold, an injection temperature abnormality signal is generated, which indicates that there may be serious temperature control problems in the injection molding process, such as a synchronization mismatch between the heat release of the molten plastic and the mold cooling system, or the temperature fluctuation caused by the injection speed exceeds the acceptable range, thereby increasing the risk of production defects.

[0113] When the injection temperature abnormal warning coefficient is less than or equal to the injection temperature abnormal warning threshold, it is determined that the injection temperature normal signal is generated, which means that the temperature control during the injection molding process is within the normal operating range, the temperature distribution is stable, and it meets the production requirements.

[0114] When receiving an abnormal injection temperature signal:

[0115] Check and adjust injection speed immediately: Based on real-time monitoring data, reduce or increase injection speed to achieve a more uniform temperature distribution.

[0116] Adjust cooling system parameters: Increase cooling flow rate or adjust cooling water temperature to ensure that the cooling system can effectively counteract heat fluctuations caused by injection speed.

[0117] Mold Temperature Adjustment: Fine-tune the mold heating system to ensure even temperature throughout the mold, especially in high-risk areas.

[0118] Production Suspension and Inspection: In some cases, if temperature anomalies may cause serious degradation of product quality, the production line may need to be suspended for a comprehensive system inspection and maintenance.

[0119] Among them, the setting of the injection temperature abnormality warning threshold is based on historical data analysis, product quality standards and safety requirements. By statistically analyzing historical production data, the critical temperature abnormality values ​​that lead to product defects and production failures are determined. Combined with the physical property requirements and quality control standards of the product, the setting of the injection temperature abnormality warning threshold is aimed at optimizing the production process, reducing the scrap rate, and ensuring operational safety. The injection temperature abnormality warning threshold should be adjusted regularly based on new production data and technological advances to maintain production efficiency and product quality.

[0120] By implementing this comprehensive temperature anomaly early warning system, temperature control during the injection molding production process has been significantly improved, ensuring a high degree of synchronization between the molten plastic and the mold cooling system, and reducing defects caused by temperature instability. This approach makes the production process more precise and responsive, helping to promptly detect and correct temperature anomalies that may lead to reduced production efficiency and product quality problems. Through real-time calculation and monitoring of early warning coefficients, the production team can quickly take measures to adjust process parameters, optimize temperature distribution, reduce scrap rates, improve production efficiency, and ensure that product quality meets design standards. In addition, the implementation of the system enhances the controllability and predictability of the process, reduces production costs, and improves market competitiveness.

[0121] Example 2

[0122] The difference between Example 2 of the present invention and Example 1 is that this example introduces a temperature control system for injection mold processing.

[0123] Figure 2 A structural schematic diagram of a temperature control system for injection mold processing of the present invention is given, which includes a mold balance judgment module, a melt chaos evaluation module, an injection permission judgment module, a synchronization mismatch analysis module, an injection speed abnormality analysis module and a temperature early warning control module.

[0124] Mold balance judgment module: Before the molten plastic is injected into the mold cavity, the temperature differences between different parts of the mold are compared through differential temperature analysis to determine whether the overall thermal balance risk level of the mold is normal.

[0125] Melting Chaos Assessment Module: Analyzes the entropy increase of the molten plastic when it is in the barrel, assesses the degree of chaos in the plastic melting process in the barrel, and classifies the degree of chaos in the plastic melting process in the barrel as abnormal or low risk.

[0126] Injection permission judgment module: When the overall thermal balance risk level of the mold is normal and the chaos level of the plastic melting process in the barrel is low risk, the molten plastic is injected from the barrel into the cavity of the mold; otherwise, the temperature operating parameters of the mold cooling system and the barrel heating system are controlled.

[0127] Synchronous mismatch analysis module: By analyzing the phase changes of thermal energy release and cooling energy absorption in the time series, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is evaluated.

[0128] Injection speed abnormality analysis module: Analyze the changes in the speed of molten plastic being injected into the mold, and evaluate the degree of adverse effects of the injection process on the stability of the temperature distribution in the mold.

[0129] Temperature early warning control module: conducts a comprehensive analysis of the degree of disorder in the plastic melting process in the barrel, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold, and the degree of adverse impact of the injection process on the stability of the temperature distribution in the mold. Based on the comprehensive analysis results, early warning control of the mold temperature is performed.

[0130] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters and thresholds in the formula are set by technicians in this field according to actual conditions.

[0131] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or may be transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that contains one or more available media sets. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium. The semiconductor medium may be a solid-state hard disk.

[0132] Those of ordinary skill in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0133] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and modules described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0134] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0135] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, and may be located in one place or distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0136] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0137] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

[0138] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0139] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A temperature control method for injection mold processing, characterized in that: The steps include: S1: Before the molten plastic is injected into the cavity of the mold, the temperature differences between different parts of the mold are compared through differential temperature analysis to determine whether the overall thermal balance risk level of the mold is normal; S2: Analyze the entropy increment of the molten plastic when it is in the barrel, evaluate the degree of disorder of the plastic melting process in the barrel, and classify the degree of disorder of the plastic melting process in the barrel as abnormal or low risk; S3: When the overall thermal balance risk level of the mold is normal and the chaos level of the plastic melting process in the barrel is low risk, the molten plastic is injected from the barrel into the cavity of the mold; otherwise, the temperature operating parameters of the mold cooling system and the barrel heating system are controlled; S4: By analyzing the phase changes of heat energy release and cooling energy absorption in the time series, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is evaluated; the change in the speed of the molten plastic injection into the mold is analyzed to evaluate the degree of adverse effects of the injection process on the stability of the temperature distribution in the mold; S5: Comprehensively analyze the degree of disorder in the plastic melting process in the barrel, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold, and the degree of adverse impact of the injection process on the stability of the temperature distribution in the mold. Based on the comprehensive analysis results, early warning control of the mold temperature is carried out; By comparing the temperature differences between different parts of the mold through differential temperature analysis, it is determined whether the overall thermal balance risk level of the mold is normal, specifically: Collect temperature data of various parts of the mold; perform statistical analysis on the temperature data of all measuring points to find out the temperature of the highest point and the lowest point in the mold, thereby calculating the maximum temperature difference of the mold; Set the maximum temperature difference threshold of the mold; When the maximum temperature difference of the mold is greater than the maximum temperature difference threshold of the mold, it is determined that the overall thermal balance potential risk level of the mold is abnormal; when the maximum temperature difference of the mold is less than or equal to the maximum temperature difference threshold of the mold, it is determined that the overall thermal balance potential risk level of the mold is normal; By analyzing the phase changes of heat energy release and cooling energy absorption in the time series, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is evaluated, specifically: Collect temperature and pressure data of molten plastic and various parts of the mold in real time; Use computational fluid dynamics software to simulate the heat transfer behavior of molten plastic in the mold and the cooling effect of the cooling system; Calculate the dynamic synchronization rate of the thermal field, and its expression is: ;in, is the thermal field dynamic synchronization rate, It is The thermal phase of the molten plastic at position, is the cooling phase of the corresponding cooling point, is the total number of measurement points, is the index; The change in the speed of molten plastic injection into the mold is analyzed to evaluate the adverse effect of the injection process on the stability of the temperature distribution in the mold, specifically: Real-time acquisition of injection speed; Setting an injection monitoring interval; obtaining the injection speeds collected within the injection monitoring interval, and numbering the injection speeds collected within the injection monitoring interval; The absolute value of the difference between two adjacent injection speeds is calculated, and the absolute value of the difference between all two adjacent injection speeds in the injection monitoring interval is summed and divided by the number of injection speeds collected in the injection monitoring interval to obtain the injection speed abnormality index.

2. A temperature control method for injection mold processing according to claim 1, characterized in that: The entropy increase of the molten plastic in the barrel is analyzed to evaluate the degree of chaos in the plastic melting process in the barrel, specifically: Calculate the microscopic state number of the barrel heating system, and its expression is: ;in, is the microscopic state number of the barrel heating system, is the base of natural logarithm, is the pressure of the molten plastic in the barrel, is the real-time temperature of the molten plastic at different positions in the barrel, is the volume occupied by the molten plastic, is the Boltzmann constant; The entropy increase melting chaos index is calculated by substituting the microscopic state number of the barrel heating system into the entropy increase formula, and its expression is: ;in, is the entropy increase melting chaos index.

3. A temperature control method for injection mold processing according to claim 2, characterized in that: Classify the degree of disturbance in the plastic melting process in the barrel as abnormal or low risk, specifically: Compare the entropy increase melting chaos index with the preset entropy increase threshold: When the entropy increase melting chaos index is greater than the preset entropy increase threshold, it is determined that the degree of chaos in the plastic melting process in the barrel is abnormal; When the entropy increase melting chaos index is less than or equal to the preset entropy increase threshold, it is determined that the chaos level of the plastic melting process in the barrel is low risk.

4. A temperature control method for injection mold processing according to claim 1, characterized in that: Control the temperature working parameters of the mold cooling system and barrel heating system, specifically: Increase the cooling water flow rate and reduce the cooling water inlet temperature; use temperature sensors to monitor the real-time temperature of each part of the mold, and adjust the opening and closing of the cooling channel through the automatic control system; Adjust the power output of the heating belt; when the temperature of the molten plastic is too high or too low, adjust the heating temperature setting of the barrel and the distribution of the heating sections; optimize the heating curve and injection speed of the barrel.

5. The temperature control method for injection mold processing according to claim 1, characterized in that: Comprehensively analyze the degree of chaos in the plastic melting process in the barrel, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold, and the degree of adverse impact of the injection process on the stability of the temperature distribution in the mold. Based on the comprehensive analysis results, early warning control of the mold temperature is carried out, specifically: The entropy increase melting chaos index, the thermal field dynamic synchronization rate and the injection speed abnormality index are normalized, and the normalized entropy increase melting chaos index, the thermal field dynamic synchronization rate and the injection speed abnormality index are respectively assigned preset proportional coefficients to calculate the injection temperature abnormality warning coefficient; Set the injection temperature abnormal warning threshold, and compare the injection temperature abnormal warning coefficient with the injection temperature abnormal warning threshold: When the injection temperature abnormal warning coefficient is greater than the injection temperature abnormal warning threshold, it is determined that an injection temperature abnormal signal is generated; When the injection temperature abnormal warning coefficient is less than or equal to the injection temperature abnormal warning threshold, it is determined that the injection temperature normal signal is generated; When an abnormal injection temperature signal is received, control measures include: immediately checking and adjusting the injection speed, adjusting the cooling system parameters, adjusting the mold temperature, and pausing and checking production.

6. A temperature control system for injection mold processing, used to implement a temperature control method for injection mold processing according to any one of claims 1 to 5, characterized in that: It includes mold balance judgment module, melting chaos assessment module, injection permission judgment module, synchronization mismatch analysis module, injection speed abnormality analysis module and temperature early warning control module; Mold balance judgment module: Before the molten plastic is injected into the mold cavity, the temperature difference between different parts of the mold is compared through differential temperature analysis to determine whether the overall thermal balance risk level of the mold is normal; Melting chaos assessment module: Analyze the entropy increase of the molten plastic in the barrel, evaluate the chaos degree of the plastic melting process in the barrel, and classify the chaos degree of the plastic melting process in the barrel as abnormal or low risk; Injection permission judgment module: When the overall thermal balance risk level of the mold is normal and the chaos level of the plastic melting process in the barrel is low risk, the molten plastic is injected from the barrel into the cavity of the mold; otherwise, the temperature operating parameters of the mold cooling system and the barrel heating system are controlled; Synchronous mismatch analysis module: By analyzing the phase changes of heat energy release and cooling energy absorption in the time series, the thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold is evaluated; Injection speed abnormality analysis module: analyzes the speed change of molten plastic injected into the mold, and evaluates the adverse effect of the injection process on the stability of the temperature distribution in the mold; Temperature early warning control module: conducts a comprehensive analysis of the degree of disorder in the plastic melting process in the barrel, the degree of thermal synchronization mismatch between the heat release of the molten plastic and the cooling system of the mold, and the degree of adverse impact of the injection process on the stability of the temperature distribution in the mold. Based on the comprehensive analysis results, early warning control of the mold temperature is performed.

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