Injection temperature control method for rapid molding of injection molded parts

Abstract

The invention discloses an injection molding temperature control method for rapid molding of injection molded parts, which relates to the field of injection molding temperature control, comprising: scanning three-dimensional spatial data of a mold, dividing the mold into main bodies in combination with geometric features, and performing structural stability evaluation and gradient calibration on the main body division results; analyzing the surface curvature of the main body division area based on the main body division results, and setting a local circuit of a cooling channel in combination with the heat distribution of an actual thermoplastic process; integrating the cooling channels of all the main body division areas into circuits, and setting the flow rate of a coolant in the cooling channel based on stress changes in the injection molded part; and based on the finally determined connectivity distribution of the cooling channels and the coolant flow rate, generating a mold and a cooling channel through 3D printing and putting them into production; the method significantly shortens the injection molding cycle, improves production efficiency and the quality and stability of injection molded parts, and is suitable for the rapid molding needs of high-precision complex injection molded parts.

Description

Technical Field

[0001] The invention relates to the field of injection molding temperature control, and in particular to an injection molding temperature control method for rapid molding of injection molded parts. Background Art

[0002] Injection molding is an important process for producing high-precision plastic parts in modern manufacturing. Its quality and efficiency largely depend on the temperature control ability of the mold. However, traditional mold cooling methods are less efficient in complex geometric molds, and cooling channels are usually arranged in a linear manner and processed by mechanical drilling. This method makes it difficult to flexibly design cooling paths for complex mold shapes, especially in areas with concentrated heat loads such as thin-walled parts, local protrusions or depressions, which can easily lead to insufficient cooling or uneven heat distribution, and then cause warping, dimensional deviations and surface defects of injection molded parts. In addition, the layout limitations of traditional cooling systems may cause the fluid to form dead corners in certain areas, reducing heat exchange efficiency, thereby extending cooling time and production cycle. With the increasing demand for complex injection molded parts, how to achieve efficient design of mold cooling channels and precise control of coolants has become a key challenge in the field of temperature control.

[0003] To this end, this solution proposes to combine mold scanning and geometric feature technology to optimize the layout of cooling channels. Through the dynamic design of local circuits and precise adjustment of coolant flow rate, a new injection molding temperature control method suitable for rapid prototyping of complex injection molding parts is formed. With the help of 3D printing technology, mold integrated manufacturing is realized, thereby improving the quality of injection molding parts and production efficiency. Summary of the invention

[0004] In order to solve the above technical problems, a method for controlling injection temperature for rapid molding of injection molded parts is provided. This technical solution solves the problems raised in the above background technology.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] An injection molding temperature control method for rapid molding of injection molded parts, comprising:

[0007] By scanning the three-dimensional spatial data of the mold, the mold is divided into main parts according to the geometric features, and the structural stability evaluation and gradient calibration are performed on the main division results;

[0008] Based on the main body division results, the surface curvature of the main body division area is analyzed, and the local circuit of the cooling channel is set according to the heat distribution of the actual thermoplastic process;

[0009] The cooling channels of all the main body areas are integrated into a circuit, and the flow rate of the coolant in the cooling channel is set based on the stress changes of the injection molded parts;

[0010] Based on the finalized connectivity distribution of the cooling channels and the coolant flow rate, the mold and cooling channels are produced by 3D printing and put into production.

[0011] Preferably, scanning the three-dimensional spatial data of the mold, dividing the mold into main bodies in combination with geometric features, and performing structural stability assessment and gradient calibration on the main body division results specifically include:

[0012] Use 3D laser scanning to obtain the 3D spatial data of the mold, perform denoising and data repair on the scanned data, remove error points, cracks and missing data generated during the scanning process, and obtain a continuous and complete 3D spatial model;

[0013] Use shape analysis algorithms to perform geometric analysis on the mold surface, identify different functional surface areas of the mold, and calibrate the geometric features of different functional surface areas;

[0014] Based on the geometric features of the mold surface, the adjacent areas of the functional surface are automatically divided through the graphic segmentation algorithm, and the adjacent areas of different functional surfaces are combined and marked as the main area;

[0015] Obtain the basic physical parameters of thermoplastics, check the stress distribution and mechanical properties of each main area through finite element analysis simulation, and perform simulation mechanical analysis on the divided main areas;

[0016] According to the simulation mechanical analysis results, the main body division results are corrected and further refined. According to the actual load capacity of the main body area, the structural stability of each main body area is gradient divided and calibrated.

[0017] Preferably, the analyzing the surface curvature of the main body divided area based on the main body division result and setting the local circuit of the cooling channel in combination with the heat distribution of the actual thermoplastic process specifically includes:

[0018] By calculating the gradient of the curvature field of each subject region surface, different regions with large changes in curvature were identified to assess the geometric complexity of the subject region surface;

[0019] According to the surface geometric complexity, regional structural stability and volume distribution of the main area, the mold is divided into regular cooling area, high-complexity cooling area and connection cooling area;

[0020] Experimental injection molding is performed on the existing initial mold to monitor the real-time temperature data of the mold cavity wall inside the mold. The conductive heat diffusion model is used to generate a continuous thermal distribution map through interpolation fitting to dynamically simulate the distribution of heat accumulation in various parts of the mold during the molding process.

[0021] Based on the distribution of heat accumulation, high heat load areas and low heat load areas are calibrated to form a heat load map;

[0022] Perform three-dimensional coverage analysis on the mold cooling zone division and heat load area map to determine the channel design plan for the coverage area.

[0023] Preferably, the three-dimensional coverage analysis of the cooling zone division and heat load area map of the mold to determine the channel design planning of the coverage area specifically includes:

[0024] The high heat load area and regular cooling area are marked as ordinary cooling area, and the corresponding cooling pipe lines adopt a straight channel design;

[0025] The overlapping area between the complex cooling area and the low heat load area is marked as the spiral cooling area, and its corresponding cooling pipe line adopts a distributed spiral cooling channel design;

[0026] The overlapping area between the cooling zone of the connection part and the low heat load area is marked as the precise cooling zone, and a grid-like parallel branch cooling channel design is adopted;

[0027] The distance between the cooling channel and the mold cavity is dynamically adjusted according to the regional heat load and the mold geometry characteristics. The specific calculation expression is: ;

[0028] In the formula, is the distance between the cooling channel and the mold cavity, is the thermal conductivity of the mold material, is the regional wall thickness, is the coolant heat transfer coefficient;

[0029] According to the actual surface area of ​​different cooling zones, the cooling pipe line density of all cooling areas is comprehensively set, requiring that the line density must reach the preset coverage rate and form independent interconnected small loops within the cooling area.

[0030] Preferably, the cooling channels of all the divided areas of the main body are integrated into a circuit, and the flow rate of the coolant in the cooling channel is set based on the stress change of the injection molded part, which specifically includes:

[0031] Obtain all independent interconnected loops in the main body divided area, set the heat load gradient based on the fitted heat distribution map, connect the interconnected loops with the same heat load gradient in series, connect the interconnected loops with different heat load gradients in parallel, and set control valves in the parallel channels;

[0032] The stress acceptance threshold is set based on the material yield strength corresponding to the type of plastic used, and stress detection devices are set in each main body division area inside the mold;

[0033] Start the injection molding process, test run the injection molding cooling system, introduce coolant into the cooling channel entrance, and monitor the stress changes in each part of the injection molding during the process of conversion from molten state to solid state;

[0034] The area where the stress of the main divided area is monitored to be greater than or equal to the stress qualified threshold is marked as a stress accumulation area, and the opening of the control valve in the parallel channel is adjusted according to the deviation ratio of the stress in the stress accumulation area exceeding the stress qualified threshold, and the coolant flow rate in the stress accumulation area is adjusted;

[0035] The injection molding cooling system is tested repeatedly until the stress of all monitored main divided areas is less than the qualified threshold value, and then the test run is terminated. The connectivity distribution of the cooling channels in the mold and the coolant flow rate are recorded at this time.

[0036] Preferably, the step of producing the mold and the cooling channel by 3D printing and putting them into production based on the finally determined connectivity distribution of the cooling channel and the coolant flow rate specifically includes:

[0037] Calculate the channel radius of the final cooling channel based on the difference in coolant flow rates of different connecting channels;

[0038] The connectivity distribution and channel radius of the cooling channel are input into the 3D printing device for batch printing of molds, and the batch molds are put into the test production line. The expected operation effect of the cooling channel is judged by the quality control feedback.

[0039] If the standards are not met, the cooling channel of the mold will be redesigned according to the above process. If the standards are met, the batch of molds will be used as the target molds and put into regular production.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] This method combines mold scanning with geometric morphology and heat distribution analysis to achieve scientific division of the main area of ​​the mold and precise layout of the cooling channels, significantly improving the cooling efficiency. Through local cooling circuit design and flow rate optimization, it is possible to achieve uniform and rapid temperature control for injection molded parts with complex shapes (such as thin walls and protruding parts), effectively reducing warping and dimensional deviations caused by heat concentration and uneven cooling. In addition, integrated manufacturing based on 3D printing technology overcomes the limitations of traditional processing methods, can flexibly realize complex channel layouts, eliminate fluid dead corners and improve cooling efficiency. This method significantly shortens the injection molding cycle and improves production efficiency. At the same time, it reduces the accumulation of thermal stress inside the mold, extends the life of the mold, and comprehensively improves the quality and stability of injection molded parts. It is particularly suitable for the rapid prototyping needs of high-precision complex injection molded parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1A flow chart of an injection temperature control method for rapid molding of injection molded parts according to the present invention;

[0043] Figure 2 The present invention scans the three-dimensional spatial data of the mold, divides the mold into main parts in combination with geometric features, and performs structural stability evaluation and gradient calibration on the main part division results;

[0044] Figure 3 The present invention analyzes the surface curvature of the main body division area based on the main body division result, and sets the cooling channel local loop flow chart in combination with the heat distribution of the actual thermoplastic process;

[0045] Figure 4 The present invention performs three-dimensional coverage analysis on the cooling zone division and heat load zone map of the mold to determine the channel design planning flow chart of the coverage area;

[0046] Figure 5 The cooling channels of all the divided areas of the main body of the present invention are integrated into a circuit, and a flow chart of the flow rate of the coolant in the cooling channel is set based on the stress change of the injection molded part;

[0047] Figure 6 The present invention is based on the final determined connectivity distribution of the cooling channels and the coolant flow rate, and generates a production flow chart of the mold and the cooling channels through 3D printing. DETAILED DESCRIPTION

[0048] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations.

[0049] Reference Figure 1 As shown, a method for controlling injection temperature for rapid molding of injection molded parts comprises:

[0050] The stress acceptance threshold is set based on the material yield strength corresponding to the type of plastic used, and stress detection devices are set in each main body division area inside the mold;

[0051] Start the injection molding process, test run the injection molding cooling system, introduce coolant into the cooling channel entrance, and monitor the stress changes in each part of the injection molding during the process of conversion from molten state to solid state;

[0052] The area where the stress of the main divided area is monitored to be greater than or equal to the stress qualified threshold is marked as a stress accumulation area, and the opening of the control valve in the parallel channel is adjusted according to the deviation ratio of the stress in the stress accumulation area exceeding the stress qualified threshold, and the coolant flow rate in the stress accumulation area is adjusted;

[0053] The injection molding cooling system is tested repeatedly until the stress of all monitored main divided areas is less than the qualified threshold value, and then the test run is terminated. The connectivity distribution of the cooling channels in the mold and the coolant flow rate are recorded at this time.

[0054] Reference Figure 2 As shown, by scanning the three-dimensional spatial data of the mold, the mold is divided into main parts in combination with geometric features, and the structural stability evaluation and gradient calibration of the main part division results are carried out, including:

[0055] 3D laser scanning is used to obtain the 3D spatial data of the mold. The scanned data is de-noised and repaired to remove the error points, cracks and missing data generated during the scanning process, and a continuous and complete 3D spatial model is obtained. The initial point cloud data volume obtained by scanning is 1 million points, of which noise points account for 5%. After repair, 95% of the valid data is retained, and finally a complete STL format model is generated, with an error control of ±0.02mm;

[0056] The shape analysis algorithm is used to perform geometric analysis on the mold surface, identify different functional surface areas of the mold, and perform initial shape (surface calibration) calibration on the geometric features of different areas. The mold functional surface can be divided into main surface, connecting surface, parting surface, auxiliary surface, guide surface, gate surface, demoulding surface, cooling surface, shrinkage compensation surface and runner surface, etc. The functional surfaces directly related to the molding of thermoplastic parts are selected for analysis.

[0057] Based on the geometric features of the functional surface area, the mold body is automatically divided through the graphic segmentation algorithm, the center point of each functional surface area is set, and the mold surface is segmented using the Region Growing Algorithm.

[0058] The specific calculation formula is: ,in, It is the geometric distance between the initial points i and j in the three-dimensional space model (iterative calculation starts from the center point of the functional surface area). The distance threshold is set according to the overall volume of the mold and then the adjacent areas are automatically generated. The adjacent areas of different functional surfaces are combined and marked as the main area.

[0059] The basic physical parameters of thermoplastics are obtained, and the stress distribution and mechanical properties of each main area are checked through finite element analysis simulation. The divided main area is subjected to simulation mechanical analysis. The material properties of thermoplastics (such as PP) are assumed to be: Young's modulus is 1.5 GPa, Poisson's ratio is 0.35, and density is 900 kg per cubic meter. There is a cylindrical complex area with a wall thickness of t=2 mm and a diameter of d=10 mm.

[0060] The ANSYS software is used to perform static mechanical analysis on this divided area. The maximum stress of each area is calculated by applying a typical load (P=5MPa) during the injection molding process: .

[0061] According to the results of the simulation mechanical analysis, the main body division results are corrected and further refined. According to the actual load capacity of the main body area, the structural stability of each main body area is gradient divided and calibrated. The gradient division method can be carried out according to the following standards:

[0062] Level 1 (high stability): Stress ,

[0063] Level 2 (Medium Stability): Stress ,

[0064] Level 3 (low stability): stress ,

[0065] Among them, low stability means that the stress load force in this area is low, and stress concentration or damage is prone to occur during the thermoplastic cooling process.

[0066] Reference Figure 3 As shown in the figure, the surface curvature of the main body division area is analyzed based on the main body division result, and the local circuit of the cooling channel is set in combination with the heat distribution of the actual thermoplastic process, including:

[0067] By calculating the gradient of the curvature field of each main area surface, it is identified that the curvature changes in different areas are large to evaluate the geometric complexity of the main area surface. The curvature distribution of the mold surface is calculated using Gaussian curvature analysis. The formula is: ,in is the Gaussian curvature of the region, and are the main curvature radii of the surface respectively. Based on the curvature distribution, the curvature greater than The part of the area is marked as complex area, which is smaller than Marked as a regular area.

[0068] According to the surface geometric complexity, regional structural stability and volume distribution of the main area, weighted summation and threshold division are performed to divide the mold into regular cooling area, highly complex cooling area and connection cooling area;

[0069] Experimental injection molding was performed on the existing initial mold to monitor the real-time temperature data of the mold cavity wall inside the mold. The conduction heat diffusion model was used to generate a continuous heat distribution map through interpolation fitting to dynamically simulate the distribution of heat accumulation in various parts of the mold during the molding process. The heat diffusion model formula is: , where T is the temperature, For time, is the thermal conductivity of the plastic are the density and specific heat of the plastic respectively.

[0070] Based on the distribution of heat accumulation, high heat load areas and low heat load areas are calibrated to form a heat load map. The discrete temperature data of the high temperature area (thin wall) and low temperature area (regular area) of the cavity wall of a certain main area are measured experimentally and brought into the heat diffusion model formula.

[0071] Perform three-dimensional coverage analysis on the mold cooling zone division and heat load area map to determine the channel design plan for the coverage area.

[0072] Reference Figure 4 As shown in the figure, the cooling zone division and heat load area map of the mold are analyzed in three dimensions to determine the channel design planning of the coverage area, including:

[0073] The high heat load area and regular cooling area are marked as ordinary cooling area. The corresponding cooling pipe line adopts a linear channel design, with uniform coolant flow rate and small resistance loss, which is suitable for large-area regular cooling areas to achieve uniform heat dissipation.

[0074] The overlapping area between the complex cooling zone and the low heat load area is marked as the spiral cooling zone. The corresponding cooling pipe line adopts a distributed spiral cooling channel design. The spiral channel increases the coolant flow path, better fits the complex curved surface, significantly improves the heat exchange area and uniformity, and is suitable for high heat load areas.

[0075] The overlapping area between the connection cooling zone and the low heat load area is marked as the precision cooling zone, and a grid-like parallel branch cooling channel design is adopted to evenly distribute the coolant in the area, which is suitable for areas that require high-precision cooling.

[0076] The distance between the cooling channel and the mold cavity is dynamically adjusted according to the regional heat load and the mold geometry characteristics. The specific calculation expression is: ;

[0077] In the formula, is the distance between the cooling channel and the mold cavity, is the thermal conductivity of the mold material, is the regional wall thickness, is the coolant heat transfer coefficient;

[0078] The actual calculation depends on the specific material of the mold, such as the thermal conductivity of the mold steel. , coolant heat transfer coefficient , wall thickness , the distance between the cooling channel and the mold cavity should be: .

[0079] According to the actual surface area of ​​different cooling zones, the cooling pipe line density of all cooling areas is comprehensively set, requiring that the line density must reach the preset coverage rate and form independent interconnected small loops within the cooling area.

[0080] Dynamically adjusting the cooling pipe line density according to the surface area of ​​the cooling area and the heat load distribution can not only meet the regional cooling needs, but also optimize resource allocation and achieve efficient heat exchange. Through the design of independent interconnected small loops, the flow continuity and uniformity of the coolant in different areas are ensured, providing technical support for the design and production of high-performance injection molds.

[0081] Through regional heat load analysis and geometric complexity evaluation, cooling zones are dynamically divided and cooling channel design is optimized. Linear, spiral and grid cooling channels are combined to meet the cooling needs of different areas, and efficient cooling is achieved by dynamically adjusting the density and spacing of pipelines. Example calculations verify the rationality of the cooling system design and provide a scientific basis for injection cooling of high-precision and complex molds.

[0082] Reference Figure 5 As shown, the cooling channels of all the main body divided areas are integrated into loops, and the flow rate of the coolant in the cooling channel is set based on the stress change of the injection molded part. Specifically, it includes:

[0083] The independent interconnected circuits in all the main divided areas are obtained, and the heat load gradient is set based on the fitted heat distribution map. The interconnected circuits with the same heat load gradient are connected in series, and the interconnected circuits with different heat load gradients are connected in parallel. At the same time, control valves are set in the parallel channels.

[0084] The series design can evenly distribute the coolant flow to meet the cooling needs of the same heat load area; the parallel design dynamically adjusts the control valve opening to prioritize the cooling needs of the high heat load area and reduce local heat concentration.

[0085] The stress acceptance threshold is set based on the material yield strength corresponding to the type of plastic used, and stress detection devices are set in each main body division area inside the mold;

[0086] Start the injection molding process, test run the injection molding cooling system, introduce coolant into the cooling channel entrance, and monitor the stress changes in each part of the injection molding during the process of conversion from molten state to solid state;

[0087] The area where the stress of the main divided area is monitored to be greater than or equal to the stress qualified threshold is marked and recorded as the stress accumulation area. The opening of the control valve in the parallel channel is adjusted according to the deviation ratio of the stress in the stress accumulation area exceeding the stress qualified threshold, and the coolant flow rate in the stress accumulation area is adjusted. The following is a specific example:

[0088] First, the safety factor is preset to 0.3. At this time, the stress qualification threshold is set to 0.3*25=7.5MPa based on the yield strength of the plastic material (such as polypropylene PP) of 25MPa;

[0089] Coolant (such as water or ethylene glycol mixture) is introduced into the cooling channel inlet, and the initial flow rate v=0.2m / s is set. The data of the stress sensor is collected in real time, and the area where the stress exceeds 7.5MPa is marked as the stress accumulation area;

[0090] For the stress accumulation area, the control valve unit adjustment opening z=0.1 is set. When the real-time monitoring stress is 10MPa, the specific adjustment process is: , and repeat this calculation step.

[0091] The injection molding cooling system is tested repeatedly until the stress of all monitored main divided areas is less than the qualified threshold value, and then the test run is terminated. The connectivity distribution of the cooling channels in the mold and the coolant flow rate are recorded at this time.

[0092] Reference Figure 6 As shown, based on the final determined connectivity distribution of the cooling channels and the coolant flow rate, the production of the mold and cooling channels by 3D printing specifically includes:

[0093] Based on the difference in coolant flow rates in different connecting channels, the channel radius and coolant flow rate of the final cooling channel are calculated. The relationship with the channel radius r is determined by the continuity equation and the fluid dynamics formula, ,in, is the coolant flow rate (obtained based on the integrated cooling circuit inlet and outlet radii), A is the cooling channel cross-sectional area, and r is the cooling channel radius.

[0094] Test run to measure flow rate ,flow , calculate the channel radius of the high heat load area: , then the subsequent mold batch printing radius parameter of the connecting channel is .

[0095] The connectivity distribution and channel radius of the cooling channel are input into the 3D printing device for batch printing of molds, and the batch molds are put into the test production line. The expected operation effect of the cooling channel is judged by the quality control feedback.

[0096] If the standards are not met, the cooling channel of the mold will be redesigned according to the above process. If the standards are met, the batch of molds will be used as the target molds and put into regular production.

[0097] Furthermore, the present solution also proposes a storage medium for an injection molding temperature control method for rapid molding of injection molded parts, on which a computer-readable program is stored, and when the computer-readable program is called, the above-mentioned injection molding temperature control method for rapid molding of injection molded parts is executed.

[0098] It is understandable that the storage medium may be a magnetic medium, such as a floppy disk, a hard disk, or a magnetic tape; an optical medium, such as a DVD; or a semiconductor medium, such as a solid state drive (SSD).

[0099] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for controlling injection temperature for rapid molding of injection molded parts, characterized in that: include: By scanning the three-dimensional spatial data of the mold, the mold is divided into main parts according to the geometric features, and the structural stability evaluation and gradient calibration of the main division results are carried out. Specifically, the following are included: Use 3D laser scanning to obtain the 3D spatial data of the mold, perform denoising and data repair on the scanned data, remove error points, cracks and missing data generated during the scanning process, and obtain a continuous and complete 3D spatial model; Use shape analysis algorithms to perform geometric analysis on the mold surface, identify different functional surface areas of the mold, and calibrate the geometric features of different functional surface areas; Based on the geometric features of the mold surface, the adjacent areas of the functional surface are automatically divided through the graphic segmentation algorithm, and the adjacent areas of different functional surfaces are combined and marked as the main area; Obtain the basic physical parameters of thermoplastics, check the stress distribution and mechanical properties of each main area through finite element analysis simulation, and perform simulation mechanical analysis on the divided main areas; According to the results of simulation mechanical analysis, the main body division results are corrected and further refined. According to the actual load capacity of the main body area, the structural stability of each main body area is gradient divided and calibrated; The surface curvature of the main body is analyzed, and the local circuit of the cooling channel is set according to the heat distribution of the actual thermoplastic process, including: By calculating the gradient of the curvature field of each subject region surface, different regions with large changes in curvature were identified to assess the geometric complexity of the subject region surface; According to the surface geometric complexity, regional structural stability and volume distribution of the main area, the mold is divided into regular cooling area, high-complexity cooling area and connection cooling area; Experimental injection molding was performed on the existing initial mold to monitor the real-time temperature data of the mold cavity wall inside the mold. The conductive heat diffusion model was used to generate a continuous thermal distribution map through interpolation fitting to dynamically simulate the distribution of heat accumulation in various parts of the mold during the molding process. Based on the distribution of heat accumulation, high heat load areas and low heat load areas are calibrated to form a heat load map; Perform three-dimensional coverage analysis on the mold cooling zone division and heat load area map to determine the channel design planning of the coverage area, including: The high heat load area and regular cooling area are marked as ordinary cooling area, and the corresponding cooling pipe lines adopt a straight channel design; The overlapping area between the complex cooling area and the low heat load area is marked as the spiral cooling area, and its corresponding cooling pipe line adopts a distributed spiral cooling channel design; The overlapping area between the cooling zone of the connection part and the low heat load area is marked as the precise cooling zone, and a grid-like parallel branch cooling channel design is adopted; The distance between the cooling channel and the mold cavity is dynamically adjusted according to the regional heat load and the mold geometry characteristics. The specific calculation expression is: ; In the formula, is the distance between the cooling channel and the mold cavity, is the thermal conductivity of the mold material, is the regional wall thickness, is the coolant heat transfer coefficient; According to the actual surface area of ​​different cooling zones, the cooling pipe line density of all cooling zones is comprehensively set, requiring the line density to reach the preset coverage rate and form an independent interconnected small loop within the cooling zone; The cooling channels of all the main body areas are integrated into a circuit, and the flow rate of the coolant in the cooling channel is set based on the stress changes of the injection molded parts; Based on the finalized connectivity distribution of the cooling channels and the coolant flow rate, the mold and cooling channels are produced by 3D printing and put into production.

2. The method for controlling injection temperature for rapid molding of injection molded parts according to claim 1, characterized in that: The circuit integration of the cooling channels of all the divided areas of the main body and setting the flow rate of the coolant in the cooling channel based on the stress change of the injection molded part specifically include: Obtain all independent interconnected loops in the main body divided area, set the heat load gradient based on the fitted heat distribution map, connect the interconnected loops with the same heat load gradient in series, connect the interconnected loops with different heat load gradients in parallel, and set control valves in the parallel channels; The stress acceptance threshold is set based on the material yield strength corresponding to the type of plastic used, and stress detection devices are set in each main body division area inside the mold; Start the injection molding process, test run the injection molding cooling system, introduce coolant into the cooling channel entrance, and monitor the stress changes in each part of the injection molding during the process of conversion from molten state to solid state; The area where the stress of the main divided area is monitored to be greater than or equal to the stress qualified threshold is marked as a stress accumulation area, and the opening of the control valve in the parallel channel is adjusted according to the deviation ratio of the stress in the stress accumulation area exceeding the stress qualified threshold, and the coolant flow rate in the stress accumulation area is adjusted; The injection molding cooling system is tested repeatedly until the stress of all monitored main divided areas is less than the qualified threshold value, and then the test run is terminated. The connectivity distribution of the cooling channels in the mold and the coolant flow rate are recorded at this time.

3. The method for controlling injection temperature for rapid molding of injection molded parts according to claim 2, characterized in that: The method of producing the mold and the cooling channel by 3D printing and putting them into production based on the finally determined connectivity distribution of the cooling channel and the coolant flow rate specifically includes: Calculate the channel radius of the final cooling channel based on the difference in coolant flow rates of different connecting channels; The connectivity distribution and channel radius of the cooling channel are input into the 3D printing device for batch printing of molds, and the batch molds are put into the test production line. The expected operation effect of the cooling channel is judged by the quality control feedback. If the standards are not met, the cooling channel of the mold will be redesigned according to the above process. If the standards are met, the batch of molds will be used as the target molds and put into regular production.

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