Injection molding method integrating mold temperature intelligent regulation and control and exhaust optimization

Abstract

The invention relates to the technical field of injection molding, and discloses an injection molding method integrating intelligent mold temperature regulation and control and exhaust optimization. 2, injection molding parameters are initialized; (3) the mold temperature is intelligently regulated and controlled; 4, exhaust collaborative optimization is carried out; 5, pressure maintaining and cooling are conducted; the mold pretreatment comprises the steps that temperature sensors and pressure sensors are evenly distributed on the surface of a cavity of the injection mold, the temperature sensors are used for collecting temperature data of different areas of the cavity in real time, and the pressure sensors are used for collecting gas pressure data in the cavity; according to the method, the multiple sets of sensors are arranged in the mold cavity, dynamic and accurate regulation and control of the mold temperature are achieved in combination with an intelligent regulation and control algorithm, heating and cooling strategies can be adjusted in real time according to the actual temperature and pressure conditions of different injection molding stages and different areas of the cavity, and the problem that the mold temperature is not uniform due to traditional constant temperature control is effectively avoided.

Description

Technical Field

[0001] This application relates to the technical field of injection molding, and in particular to an injection molding method that integrates intelligent mold temperature control and venting optimization. Background Technology

[0002] Injection molding is one of the most widely used processing methods in the production of plastic products. It involves injecting molten plastic raw materials into a mold cavity, which then cools and solidifies to obtain the desired product.

[0003] During the injection molding process, mold temperature control and venting are key factors affecting product quality: excessively high mold temperature can lead to uneven shrinkage and warping deformation of the product, while excessively low mold temperature will reduce the fluidity of the plastic melt, resulting in defects such as material shortage and weld lines; if the gas in the mold cavity cannot be vented in time, it will form bubbles, burn, and surface depressions inside the product, seriously affecting the mechanical properties and appearance quality of the product.

[0004] However, in practical applications, most existing mold temperature control systems employ traditional constant temperature control methods, using heaters and cooling water pipes to regulate mold temperature. This method suffers from slow response times and cannot dynamically adjust the mold temperature in real time based on the flow state of the molten plastic and the cavity filling progress during injection molding, resulting in low control precision. Furthermore, the venting structures are mostly fixed venting channels or holes, offering limited venting efficiency and prone to clogging due to molten plastic overflow. This makes it difficult to adapt to the venting requirements of different types of plastic products and various injection molding process parameters. In addition, existing technologies treat mold temperature control and venting systems independently, failing to create synergy and hindering the improvement of injection molded product quality and production efficiency through coordinated optimization of mold temperature and venting.

[0005] Therefore, those skilled in the art have provided an injection molding method that integrates intelligent mold temperature control and venting optimization to solve the problems mentioned in the background art. Summary of the Invention

[0006] To address the issue that most mold temperature control methods mentioned in the background technology employ traditional constant temperature control, relying on heaters and cooling water pipes for temperature regulation, this approach suffers from slow response times and lacks the ability to dynamically adjust the mold temperature in real time based on the flow state of the molten plastic and the cavity filling progress during injection molding, resulting in low control precision. Furthermore, the venting structures are often fixed venting channels or holes, leading to limited venting efficiency and a tendency for molten plastic to overflow and clog the venting channels, making it difficult to adapt to the venting requirements of different types of plastic products and different injection molding process parameters. In addition, in existing technologies, mold temperature control and venting systems are independent and lack synergy, failing to improve the quality and production efficiency of injection molded products through coordinated optimization of mold temperature and venting. Therefore, this application provides an injection molding method that integrates intelligent mold temperature control and venting optimization.

[0007] This application provides an injection molding method that integrates intelligent mold temperature control and venting optimization, employing the following technical solution: including the following steps:

[0008] Step 1: Mold pretreatment;

[0009] Step 2: Initialize injection molding parameters;

[0010] Step 3: Intelligent mold temperature control;

[0011] Step 4: Exhaust system optimization;

[0012] Step 5: Pressure holding and cooling;

[0013] Step 6: Iterative optimization of process parameters.

[0014] Preferably, the mold pretreatment includes uniformly arranging temperature sensors and pressure sensors on the surface of the injection mold cavity. The temperature sensors are used to collect temperature data in different areas of the cavity in real time, and the pressure sensors are used to collect gas pressure data inside the cavity. A multi-stage venting structure is opened in areas prone to gas accumulation, such as the parting surface and the end of the melt flow of the mold. The multi-stage venting structure includes a main venting groove, an auxiliary venting groove, and micro venting holes. The main venting groove has a width of 0.8-1.2 mm and a depth of 0.3-0.5 mm. The auxiliary venting groove is perpendicularly connected to the main venting groove, with a width of 0.4-0.6 mm and a depth of 0.1-0.2 mm. The micro venting holes are evenly distributed at the end of the auxiliary venting groove, with a diameter of 0.05-0.1 mm. A one-way venting valve is set at the outlet of the micro venting hole to prevent melt overflow.

[0015] Preferably, the initialization of injection molding parameters is based on the material (such as PP, ABS, PC, etc.) and structural dimensions of the injection molded product, and presets basic parameters such as initial mold temperature range, injection pressure, injection speed, and holding time; the initial mold temperature range is divided into three intervals: melt filling stage, holding pressure stage, and cooling stage. The initial mold temperature in the filling stage is the material melting point + 20-30℃, the initial mold temperature in the holding pressure stage is the material melting point + 5-10℃, and the initial mold temperature in the cooling stage is room temperature + 30-50℃.

[0016] Preferably, the intelligent mold temperature control includes:

[0017] When the injection molding machine is started, the molten plastic is heated and melted in the barrel and then injected into the mold cavity. Temperature and pressure sensors transmit the collected temperature and gas pressure data to the central controller in real time. The central controller analyzes and processes the data through a preset intelligent control algorithm.

[0018] S1: When the temperature of a certain area of ​​the cavity is detected to be lower than the lower limit of the preset temperature of the corresponding stage, and the pressure sensor detects that the gas pressure in that area is higher than the preset threshold, the central controller controls the mold temperature regulation module (including electric heater and cooling water pipeline) corresponding to that area to start the heating mode, so as to quickly raise the temperature through the electric heater, and at the same time adjust the flow valve of the cooling water pipeline to reduce the cooling water flow rate until the temperature of that area reaches the preset range.

[0019] S2: When the temperature of a certain area of ​​the cavity is detected to be higher than the upper limit of the preset temperature for the corresponding stage, and the melt filling speed is normal, the central controller controls the mold temperature regulation module to start the cooling mode, increase the flow rate of the cooling water pipe, and at the same time turn off some electric heaters to ensure that the mold temperature is stable within the preset range.

[0020] S3: During the melt filling process, the mold temperature gradient is dynamically adjusted based on the rate of change of gas pressure collected by the pressure sensor. The faster the rate of change of gas pressure, the smoother the venting, and the response sensitivity of the mold temperature adjustment can be appropriately reduced. The slower the rate of change of gas pressure, the greater the risk of gas accumulation, and the mold temperature in the corresponding area needs to be increased to enhance melt fluidity and assist in venting.

[0021] Preferably, the exhaust gas synergistic optimization includes:

[0022] While intelligently controlling the mold temperature, the central controller adjusts the working status of the multi-stage venting structure in real time based on the cavity gas pressure data collected by the pressure sensor.

[0023] S1: When the gas pressure is lower than the first preset pressure value (0.1-0.2MPa), only the main exhaust channel and the auxiliary exhaust channel work, and the micro exhaust hole is closed to avoid excessive loss of melt;

[0024] S2: When the gas pressure is between the first preset pressure value and the second preset pressure value (0.2-0.3MPa), the central controller controls the one-way exhaust valve to open and the micro exhaust port to start working, thereby enhancing the exhaust efficiency.

[0025] S3: When the gas pressure is higher than the second preset pressure value, the central controller will increase the mold temperature in the corresponding area and control the injection molding machine to briefly reduce the injection speed (the reduction range is 10-20%) to prolong the gas discharge time. After the gas pressure drops below the second preset pressure value, the normal injection speed will be restored.

[0026] Preferably, the pressure holding and cooling refer to the following steps: after the melt filling is completed, the pressure holding stage is entered. The central controller stabilizes the mold temperature within the preset range of the pressure holding stage based on the mold temperature data collected by the temperature sensor, while the venting structure continues to work to expel the small amount of gas generated during the pressure holding process. After the pressure holding is completed, the cooling stage is entered. The intelligent mold temperature control system gradually reduces the mold temperature to the preset range of the cooling stage until the product cools and solidifies, and finally the mold is opened and the part is removed.

[0027] Preferably, the process parameter iterative optimization refers to the central controller recording the mold temperature change curve, gas pressure change curve, and product quality inspection data (such as whether there are bubbles, weld lines, warpage, etc.) during each injection molding process after completion. The intelligent control parameters are iteratively optimized through machine learning algorithms to update the optimal mold temperature range and venting structure working parameters under different working conditions, providing a more accurate control basis for the next injection molding.

[0028] In summary, this application includes the following beneficial technical effects:

[0029] 1. This invention achieves dynamic and precise control of mold temperature by arranging multiple sets of sensors in the mold cavity and combining them with intelligent control algorithms. It can adjust the heating and cooling strategies in real time according to the actual temperature and pressure conditions in different areas of the cavity at different stages of injection molding, effectively avoiding the problem of uneven mold temperature caused by traditional constant temperature control and improving the molding stability of the product.

[0030] 2. The design combines a multi-stage venting structure with a one-way venting valve, which ensures high venting efficiency and prevents melt overflow from blocking the venting channel. At the same time, the working state of the venting structure is dynamically adjusted by gas pressure data to adapt to the venting requirements of different injection molding conditions.

[0031] 3. It achieves coordinated operation of mold temperature control and venting optimization. It assists venting by adjusting the mold temperature gradient and optimizes mold temperature control parameters by venting status feedback. The two work together to significantly reduce the incidence of defects such as bubbles, weld lines, and warpage in the products, thereby improving product quality and production efficiency.

[0032] 4. By introducing machine learning algorithms for iterative optimization of process parameters, the injection molding method becomes adaptive and can continuously optimize control parameters as production batches increase. It is applicable to the injection molding production of plastic products of various materials and different structural dimensions, and has strong versatility. Detailed Implementation

[0033] The described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0034] This application discloses an injection molding method that integrates intelligent mold temperature control and venting optimization, including the following steps:

[0035] Step 1: Mold pretreatment;

[0036] Step 2: Initialize injection molding parameters;

[0037] Step 3: Intelligent mold temperature control;

[0038] Step 4: Exhaust system optimization;

[0039] Step 5: Pressure holding and cooling;

[0040] Step 6: Iterative optimization of process parameters.

[0041] In this application, mold pretreatment includes uniformly arranging temperature sensors and pressure sensors on the surface of the injection mold cavity. The temperature sensors are used to collect temperature data in different areas of the cavity in real time, and the pressure sensors are used to collect gas pressure data inside the cavity. Multi-stage venting structures are opened in areas prone to gas accumulation, such as the parting surface and the end of melt flow in the mold. The multi-stage venting structure includes a main venting groove, an auxiliary venting groove, and micro venting holes. The main venting groove has a width of 0.8-1.2 mm and a depth of 0.3-0.5 mm. The auxiliary venting groove is perpendicularly connected to the main venting groove, with a width of 0.4-0.6 mm and a depth of 0.1-0.2 mm. The micro venting holes are evenly distributed at the end of the auxiliary venting groove, with a diameter of 0.05-0.1 mm. A one-way venting valve is set at the outlet of the micro venting hole to prevent melt overflow.

[0042] In this application, the injection molding parameters are initialized based on the material (such as PP, ABS, PC, etc.) and structural dimensions of the injection molded product, and basic parameters such as the initial mold temperature range, injection pressure, injection speed, and holding time are preset. The initial mold temperature range is divided into three intervals: melt filling stage, holding pressure stage, and cooling stage. The initial mold temperature in the filling stage is the material melting point + 20-30℃, the initial mold temperature in the holding pressure stage is the material melting point + 5-10℃, and the initial mold temperature in the cooling stage is room temperature + 30-50℃.

[0043] In this application, intelligent mold temperature control includes:

[0044] When the injection molding machine is started, the molten plastic is heated and melted in the barrel and then injected into the mold cavity. Temperature and pressure sensors transmit the collected temperature and gas pressure data to the central controller in real time. The central controller analyzes and processes the data through a preset intelligent control algorithm.

[0045] S1: When the temperature of a certain area of ​​the cavity is detected to be lower than the lower limit of the preset temperature of the corresponding stage, and the pressure sensor detects that the gas pressure in that area is higher than the preset threshold, the central controller controls the mold temperature regulation module (including electric heater and cooling water pipeline) corresponding to that area to start the heating mode, so as to quickly raise the temperature through the electric heater, and at the same time adjust the flow valve of the cooling water pipeline to reduce the cooling water flow rate until the temperature of that area reaches the preset range.

[0046] S2: When the temperature of a certain area of ​​the cavity is detected to be higher than the upper limit of the preset temperature for the corresponding stage, and the melt filling speed is normal, the central controller controls the mold temperature regulation module to start the cooling mode, increase the flow rate of the cooling water pipe, and at the same time turn off some electric heaters to ensure that the mold temperature is stable within the preset range.

[0047] S3: During the melt filling process, the mold temperature gradient is dynamically adjusted based on the rate of change of gas pressure collected by the pressure sensor. The faster the rate of change of gas pressure, the smoother the venting, and the response sensitivity of the mold temperature adjustment can be appropriately reduced. The slower the rate of change of gas pressure, the greater the risk of gas accumulation, and the mold temperature in the corresponding area needs to be increased to enhance melt fluidity and assist in venting.

[0048] In this application, exhaust gas co-optimization includes:

[0049] While intelligently controlling the mold temperature, the central controller adjusts the working status of the multi-stage venting structure in real time based on the cavity gas pressure data collected by the pressure sensor.

[0050] S1: When the gas pressure is lower than the first preset pressure value (0.1-0.2MPa), only the main exhaust channel and the auxiliary exhaust channel work, and the micro exhaust hole is closed to avoid excessive loss of melt;

[0051] S2: When the gas pressure is between the first preset pressure value and the second preset pressure value (0.2-0.3MPa), the central controller controls the one-way exhaust valve to open and the micro exhaust port to start working, thereby enhancing the exhaust efficiency.

[0052] S3: When the gas pressure is higher than the second preset pressure value, the central controller will increase the mold temperature in the corresponding area and control the injection molding machine to briefly reduce the injection speed (the reduction range is 10-20%) to prolong the gas discharge time. After the gas pressure drops below the second preset pressure value, the normal injection speed will be restored.

[0053] In this application, holding pressure and cooling refer to the following steps: after the melt filling is completed, the mold enters the holding pressure stage. The central controller stabilizes the mold temperature within the preset range of the holding pressure stage based on the mold temperature data collected by the temperature sensor, while the venting structure continues to work to expel the small amount of gas generated during the holding pressure process. After the holding pressure is completed, the mold enters the cooling stage. The intelligent mold temperature control system gradually reduces the mold temperature to the preset range of the cooling stage until the product cools and solidifies. Finally, the mold is opened and the part is removed.

[0054] In this application, process parameter iterative optimization refers to the process where, after each injection molding is completed, the central controller records the mold temperature change curve, gas pressure change curve, and product quality inspection data (such as whether there are bubbles, weld lines, warpage, etc.) during the injection molding process, and uses machine learning algorithms to iteratively optimize the intelligent control parameters, update the optimal mold temperature range and venting structure working parameters under different working conditions, and provide a more accurate control basis for the next injection molding.

[0055] All standard parts used in this invention can be purchased from the market, and irregular parts can be customized according to the description in the specification. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts and equipment adopt conventional models in the prior art, and the circuit connection adopts conventional connection methods in the prior art, which will not be described in detail here.

[0056] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0057] Secondly: In the embodiments disclosed in this invention, only the structures involved in the embodiments disclosed in this invention are involved. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other.

Claims

1. An injection molding method integrating intelligent mold temperature control and venting optimization, comprising the following steps: Step 1: Mold pretreatment; Step 2: Initialize injection molding parameters; Step 3: Intelligent mold temperature control; Step 4: Exhaust system optimization; Step 5: Pressure holding and cooling; Step 6: Iterative optimization of process parameters.

2. The injection molding method integrating intelligent mold temperature control and venting optimization according to claim 1, characterized in that: The mold pretreatment includes uniformly arranging temperature sensors and pressure sensors on the surface of the injection mold cavity. The temperature sensors are used to collect temperature data in different areas of the cavity in real time, and the pressure sensors are used to collect gas pressure data inside the cavity. A multi-stage venting structure is set in areas prone to gas accumulation, such as the parting surface and the end of the melt flow of the mold. The multi-stage venting structure includes a main venting groove, an auxiliary venting groove, and micro venting holes. The main venting groove has a width of 0.8-1.2 mm and a depth of 0.3-0.5 mm. The auxiliary venting groove is perpendicularly connected to the main venting groove, with a width of 0.4-0.6 mm and a depth of 0.1-0.2 mm. The micro venting holes are evenly distributed at the end of the auxiliary venting groove, with a diameter of 0.05-0.1 mm. A one-way venting valve is set at the outlet of the micro venting hole to prevent melt overflow.

3. The injection molding method integrating intelligent mold temperature control and venting optimization according to claim 1, characterized in that: The initialization of injection molding parameters is based on the material (such as PP, ABS, PC, etc.) and structural dimensions of the injection molded product, and presets basic parameters such as initial mold temperature range, injection pressure, injection speed, and holding time. The initial mold temperature range is divided into three intervals: melt filling stage, holding pressure stage, and cooling stage. The initial mold temperature in the filling stage is the material melting point + 20-30℃, the initial mold temperature in the holding pressure stage is the material melting point + 5-10℃, and the initial mold temperature in the cooling stage is room temperature + 30-50℃.

4. The injection molding method integrating intelligent mold temperature control and venting optimization according to claim 1, characterized in that: The intelligent mold temperature control includes: When the injection molding machine is started, the molten plastic is heated and melted in the barrel and then injected into the mold cavity. Temperature and pressure sensors transmit the collected temperature and gas pressure data to the central controller in real time. The central controller analyzes and processes the data through a preset intelligent control algorithm. S1: When the temperature of a certain area of ​​the cavity is detected to be lower than the lower limit of the preset temperature of the corresponding stage, and the pressure sensor detects that the gas pressure in that area is higher than the preset threshold, the central controller controls the mold temperature regulation module (including electric heater and cooling water pipeline) corresponding to that area to start the heating mode, so as to quickly raise the temperature through the electric heater, and at the same time adjust the flow valve of the cooling water pipeline to reduce the cooling water flow rate until the temperature of that area reaches the preset range. S2: When the temperature of a certain area of ​​the cavity is detected to be higher than the upper limit of the preset temperature for the corresponding stage, and the melt filling speed is normal, the central controller controls the mold temperature regulation module to start the cooling mode, increase the flow rate of the cooling water pipe, and at the same time turn off some electric heaters to ensure that the mold temperature is stable within the preset range. S3: During the melt filling process, the mold temperature gradient is dynamically adjusted based on the rate of change of gas pressure collected by the pressure sensor. The faster the rate of change of gas pressure, the smoother the venting, and the response sensitivity of the mold temperature adjustment can be appropriately reduced. The slower the rate of change of gas pressure, the greater the risk of gas accumulation, and the mold temperature in the corresponding area needs to be increased to enhance melt fluidity and assist in venting.

5. The injection molding method integrating intelligent mold temperature control and venting optimization according to claim 1, characterized in that: The exhaust gas synergistic optimization includes: While intelligently controlling the mold temperature, the central controller adjusts the working status of the multi-stage venting structure in real time based on the cavity gas pressure data collected by the pressure sensor. S1: When the gas pressure is lower than the first preset pressure value (0.1-0.2MPa), only the main exhaust channel and the auxiliary exhaust channel work, and the micro exhaust hole is closed to avoid excessive loss of melt; S2: When the gas pressure is between the first preset pressure value and the second preset pressure value (0.2-0.3MPa), the central controller controls the one-way exhaust valve to open and the micro exhaust port to start working, thereby enhancing the exhaust efficiency. S3: When the gas pressure is higher than the second preset pressure value, the central controller will increase the mold temperature in the corresponding area and control the injection molding machine to briefly reduce the injection speed (the reduction range is 10-20%) to prolong the gas discharge time. After the gas pressure drops below the second preset pressure value, the normal injection speed will be restored.

6. The injection molding method integrating intelligent mold temperature control and venting optimization according to claim 1, characterized in that: The pressure holding and cooling process refers to the process after the melt filling is completed, entering the pressure holding stage. The central controller stabilizes the mold temperature within the preset range of the pressure holding stage based on the mold temperature data collected by the temperature sensor, while the venting structure continues to work to expel the small amount of gas generated during the pressure holding process. After the pressure holding is completed, the cooling stage begins. The intelligent mold temperature control system gradually reduces the mold temperature to the preset range of the cooling stage until the product cools and solidifies, and finally the mold is opened and the part is removed.

7. The injection molding method integrating intelligent mold temperature control and venting optimization according to claim 1, characterized in that: The process parameter iterative optimization refers to the process where, after each injection molding is completed, the central controller records the mold temperature change curve, gas pressure change curve, and product quality inspection data (such as whether there are bubbles, weld lines, warpage, etc.) during the injection molding process. Then, iterative optimization of the intelligent control parameters is performed through machine learning algorithms to update the optimal mold temperature range and venting structure working parameters under different working conditions, providing a more accurate control basis for the next injection molding.