Resin molding analysis method, program, and recording medium

Abstract

To provide a resin molding analysis method capable of accurately performing a resin flow analysis in a molded product according to a shape of the molded product.SOLUTION: A resin molding analysis method includes the steps for: performing a resin flow analysis during resin molding; obtaining a plurality of correction methods, including target parameters to be corrected and correction values in the flow analysis, for correcting an analysis result of the flow analysis to match a measured value, based on the analysis result of the flow analysis and the measured value of a resin molded product; and performing a resin flow analysis in a molded product of arbitrary shape using the obtained correction method.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] This invention relates to a resin molding analysis method, a program, and a recording medium.

Background Art

[0002] Conventionally, a resin molding analysis method has been known (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses a resin molding analysis method for performing a flow analysis of resin during resin molding. In the resin molding analysis method of Patent Document 1, the quality of a resin molded product is configured to be accurately predicted by correcting the inherent machine differences (individual differences) of an injection molding machine. Specifically, it is configured to perform analysis by adjusting parameters as molding conditions according to each injection molding machine.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the resin molding analysis method of Patent Document 1, since analysis is performed by adjusting parameters as molding conditions according to each injection molding machine, it is possible to adjust the parameters as molding conditions to appropriate values so as to cope with the inherent machine differences (individual differences) of the injection molding machine. However, it is difficult to adjust the parameters as molding conditions to appropriate values so as to cope with the shape of the molded product. For this reason, there is a problem that it is difficult to accurately perform a flow analysis of the resin of the molded product according to the shape of the molded product.

[0006] This invention was made to solve the above-mentioned problems, and one of its objectives is to provide a resin molding analysis method, program, and recording medium that can accurately analyze the resin flow of a molded product according to the shape of the molded product. [Means for solving the problem]

[0007] To achieve the above objective, the resin molding analysis method according to the first aspect of this invention comprises the steps of performing a flow analysis of the resin during resin molding, and based on the analysis results of the flow analysis and the measured values ​​of the resin molded product, By performing a forward analysis on the analysis conditions, setting an objective function from the difference between the forward analysis results and the design target values, and then determining the sensitivity of the design parameters that minimize or maximize the objective function through inverse analysis, a sensitivity distribution is obtained as an indicator of the magnitude of the difference between the analysis results and the measured values, and by increasing or decreasing the correction amount according to the magnitude of the sensitivity of the sensitivity distribution, The process involves obtaining multiple correction methods, including the parameters to be corrected and the correction values ​​in the fluid analysis, in order to correct the analysis results of the fluid analysis to match the measured values, and then using the correction method with the closest conditions among the obtained multiple correction methods. By setting target parameters at a predetermined position on a molded product of any shape and performing analysis processing, The system includes a step of performing a flow analysis of the resin of a molded product of any shape.

[0008] In the resin molding analysis method according to the first aspect of this invention, as described above, multiple correction methods are acquired, including the target parameters to be corrected and the correction values ​​in the flow analysis, for correcting the analysis results of the flow analysis to match the measured values, and the resin flow analysis of a molded product of any shape is performed using the acquired correction methods. As a result, the target parameters can be corrected according to the shape of the molded product and the resin flow analysis can be performed, so that the resin flow analysis of the molded product can be performed with high accuracy according to the shape of the molded product. Furthermore, since the target parameters can be corrected for a molded product of any shape at a predetermined position where the acquired correction method is similar, and resin flow analysis can be performed, the target parameters for resin flow analysis of a molded product of any shape can be easily corrected and set. In addition, since the target parameters can be corrected at positions where the sensitivity as an indicator of the difference between the analysis result and the measured value is high, the analysis result of the flow analysis can be easily brought closer to the measured value.

[0010] In this case, preferably, the step of performing a resin flow analysis on a molded product of any shape includes determining a predetermined position for the flow analysis based on at least one of the following: resin flow length, thickness of the molded product, determination of core-side or cavity-side region in the mold, anisotropic shrinkage, distance from the end of the molded product, distance from the nozzle, mold temperature variation, rib portion of the molded product, boss portion of the molded product, position relative to the cooling water pipe, position relative to the ejector pin, and position relative to the parting line surface, and performing the analysis process using a correction method. With this configuration, a predetermined position where the resin flow state is common can be easily determined based on at least one of the following: resin flow length, thickness of the molded product, determination of core-side or cavity-side region in the mold, anisotropic shrinkage, distance from the end of the molded product, distance from the nozzle, mold temperature variation, rib portion of the molded product, boss portion of the molded product, position relative to the cooling water pipe, position relative to the ejector pin, and position relative to the parting line surface.

[0012] In the resin molding analysis method according to the first aspect described above, preferably, the step of performing a resin flow analysis of a molded product of any shape is to use a correction method to set at least one of the resin flow characteristics, resin physical properties, and warpage deformation parameters as parameters to be corrected in the flow analysis, and then perform the analysis. With this configuration, the resin flow characteristics, resin physical properties, or warpage deformation parameters can be corrected as target parameters, and the resin flow analysis of the molded product can be performed with high accuracy according to the shape of the molded product.

[0013] The program according to the second aspect of this invention causes a computer to execute the resin molding analysis method according to the first aspect.

[0014] In the program according to the second aspect of this invention, by having a computer execute the resin molding analysis method according to the first aspect described above, it is possible to perform a highly accurate analysis of the resin flow of a molded product according to the shape of the molded product.

[0015] The storage medium according to the third aspect of the present invention stores the program according to the second aspect and is readable by a computer.

[0016] In the storage medium according to the third aspect of the present invention, by recording the program according to the second aspect, it is possible to provide a computer-readable recording medium capable of accurately performing a resin flow analysis of a molded product according to the shape of the molded product.

Advantages of the Invention

[0017] According to the present invention, as described above, it is possible to accurately perform a resin flow analysis of a molded product according to the shape of the molded product.

Brief Description of the Drawings

[0018] [Figure 1] It is a block diagram showing a configuration example for implementing a resin molding analysis method according to an embodiment. [Figure 2] It is a diagram showing an example of the shape of a molded product according to an embodiment. [Figure 3] It is a diagram showing an example of a filling pattern at the time of resin injection of a molded product according to an embodiment. [Figure 4] It is a diagram showing an example of warpage deformation of a molded product according to an embodiment. [Figure 5] It is a diagram for explaining an evaluation position of a molded product according to an embodiment. [Figure 6] It is a diagram showing an example of a sensitivity distribution of a molded product according to an embodiment. [Figure 7] It is a diagram showing an example of correction of shrinkage distortion of a molded product according to an embodiment. [Figure 8] It is a flowchart for explaining an acquisition process of extended parameters according to an embodiment. [Figure 9] It is a flowchart for explaining an analysis process using extended parameters according to an embodiment. [Figure 10] a It is a flowchart for explaining a filling pattern analysis process according to an embodiment. [Figure 11] It is a diagram showing an example of a filling pattern according to an embodiment. [Figure 12] It is a diagram for explaining an example of evaluating the roundness of the cylinder of a molded product according to an embodiment.

Mode for Carrying Out the Invention

[0019] Hereinafter, embodiments embodying the present invention will be described based on the drawings.

[0020] Referring to FIGS. 1 to 11, a resin molding analysis method according to an embodiment will be described.

[0021] The resin molding analysis method according to the present embodiment is a method for performing a flow analysis of a molded product and predicting the state of the molded product. Specifically, it is a method for predicting the occurrence of defects in the molded product.

[0022] (Example of device configuration) The resin molding analysis method according to the present embodiment can be implemented by causing a computer 1 to execute a program 3a. The resin molding analysis method can be implemented, for example, by a device configuration as shown in FIG. 1. The computer 1 is configured to be able to execute the program 3a. By causing the computer 1 to execute the program 3a, a resin molding analysis device 100 is configured. Part or all of the processing performed by causing the computer 1 to execute the program 3a may be performed by hardware such as a dedicated arithmetic circuit.

[0023] In the configuration example of FIG. 1, the computer 1 includes one or more processors 2 composed of a CPU (Central Processing Unit) or the like, and a storage unit 3 including a ROM (Read Only Memory), a RAM (Random Access Memory), and a storage device. The storage device is, for example, a hard disk drive or a semiconductor storage device.

[0024] Computer 1 can perform resin molding analysis by having the processor 2 execute the program 3a stored in the memory unit 3. The program 3a can be read from the recording medium 7, or it may be provided from an external server via a transmission path 8 such as the Internet or a LAN (Local Area Network). The recording medium 7 is a computer-readable recording medium such as an optical disk, magnetic disk, or non-volatile semiconductor memory, on which the program 3a is recorded.

[0025] The memory unit 3 stores not only the program 3a but also various analysis data 3b used for performing resin molding analysis. The analysis data 3b stores resin molding information including resin molding condition information and the characteristics of the molded resin product, parameters for simulating the state of the resin during molding and the details of the molded product's characteristics, product category information, shape features, a group of optimal parameters, error rates, numerical data used for analysis, and analysis condition data.

[0026] Furthermore, the computer 1 includes a display unit 4 such as a liquid crystal display, an input unit 5 consisting of input devices such as a keyboard and mouse, and a reading unit 6 for reading programs 3a and various data from a recording medium 7. The reading unit 6 is a reader device depending on the type of recording medium 7. Analysis condition data can be input by the user using the input unit 5. Analysis data 3b may be read from a recording medium created by the user, or it may be created by the user on an external server and obtained from the external server via a transmission path 8.

[0027] (Resin molding analysis method) Next, the resin molding analysis method will be described. In this embodiment, multiple correction methods, including the target parameters to be corrected and the correction values ​​in the flow analysis, are acquired, and the resin flow analysis of a molded product of any shape is performed by performing corrections using the acquired correction methods.

[0028] In the resin analysis method, the molded product is divided into multiple analysis meshes (small elements), and analysis mesh information, material data, molding conditions, and analysis parameters are input. Based on this input information, the injection molding is analyzed. The analysis results output information such as resin filling pattern, resin pressure, temperature, resin orientation, physical properties, warp deformation, roundness, filling pattern, geometric tolerances, and predicted locations of appearance defects (welds, sink marks, flow marks, burning, silver streaks).

[0029] For example, the information entered for analysis includes product category information (application, field), analysis (calculation) mesh information (element type, number of elements, number of nodes, division conditions, element quality), resin data (resin manufacturer, grade name, base resin, latent heat, solidification temperature, density, specific heat, thermal conductivity, melt viscosity, PVT data, elastic modulus, Poisson's ratio, coefficient of linear expansion, molding shrinkage rate, mechanical strength, reinforcing material properties, reinforcing material content, viscoelastic properties (Prony series, shift factor), optical properties (stress optical coefficient, photoelastic coefficient, refractive index, molecular structure, gelation reaction rate, curing reaction heat)), molding conditions (time, This includes information such as filling rate, pressure limit, screw position, screw speed, flow rate, metering position, resin temperature, mold temperature, VP switching timing, holding pressure, holding pressure time, in-mold cooling conditions, cycle time), mold conditions (nozzle position, gate position, parting surface, number of gates, runner layout, cooling circuit, ejector pin arrangement), boundary conditions (flow rate and pressure at the nozzle, heat transfer coefficient, ambient temperature, ambient humidity), molding machine information (molding machine manufacturer name, molding machine model number, maximum injection speed, maximum injection pressure, maximum holding pressure, screw diameter, maximum clamping force, maximum injection volume), and molded product rigidity information.

[0030] Analysis parameters can be set by the user performing the analysis. However, if the parameters become diverse and complex, the analysis results will differ depending on the skill of the user setting the parameter values.

[0031] Here, the mathematical models used in simulations do not reflect all real-world phenomena, and modeling errors occur. In real-world phenomena, many values ​​are not always constant and include variations, such as the effect of different resin batches on material properties or the heat transfer coefficient within a mold. However, since it is difficult to grasp this fact precisely, ideal conditions are often assumed, and constant values ​​are set in time and space, and these influences also become sources of error.

[0032] For example, consider a case where the warpage deformation of an injection-molded product does not match the measured value or the predicted value (analysis result). To investigate the cause, it is first necessary to identify the factors causing the discrepancy between the analysis and the measurement. In analysis, it is possible to save the data during the calculation process and retrieve and verify the data later. On the other hand, actual molded products do not retain historical information from the time the molten resin is poured into the mold until it cools and is removed, making it difficult to compare the two. As a result, it is usually difficult to identify the cause of the discrepancy between the measured value and the analysis value.

[0033] The analysis software includes analytical parameters for adjusting accuracy and applying corrections to the analysis. By adjusting the values ​​of these analytical parameters, it is possible to estimate parameters that match the measured values ​​by applying corrections to the analysis. Various studies have been conducted to efficiently estimate the optimal parameters. For example, one could combine injection molding simulation with parametric optimization, calculating injection molding simulations with slightly varying parameter values ​​and adopting the one with the smallest error.

[0034] Furthermore, injection molding simulations are known to exhibit strong nonlinearity in their control variables (input values) and target variables (output values). For parameter estimation in cases of strong nonlinearity, machine learning techniques such as multilayer neural networks may be used.

[0035] In this embodiment, the resin molding analysis method comprises the steps of: performing a flow analysis of the resin during resin molding; acquiring multiple correction methods, including target parameters and correction values ​​in the flow analysis, for correcting the flow analysis results to match the measured values, based on the analysis results of the flow analysis and the measured values ​​of the resin molded product; and performing a flow analysis of the resin of a molded product of an arbitrary shape using the acquired correction methods. The measured values ​​may be, for example, measured values ​​of molded products similar to the injection molded product, empirical values, or estimated values.

[0036] In other words, by acquiring the target parameters and correction values ​​for the correction method, it becomes possible to set parameters for accurate analysis by using the acquired correction method under similar conditions (similar shape, molding conditions, and resin used) when performing a new analysis.

[0037] Furthermore, in this embodiment, the step of performing a resin flow analysis of a molded product of any shape includes setting target parameters at a predetermined position of the molded product of any shape using a correction method and performing the analysis process. For example, the step of performing a resin flow analysis of a molded product of any shape includes determining a predetermined position for the flow analysis based on at least one of the following: resin flow length, wall thickness of the molded product, determination of core-side or cavity-side region in the mold, anisotropic shrinkage, distance from the end of the molded product, distance from the nozzle, mold temperature variation, rib portion of the molded product, boss portion of the molded product, position relative to the cooling water pipe, position relative to the ejector pin, and position relative to the parting line surface, and performing the analysis process using a correction method.

[0038] Here, to determine the predetermined position of a molded product of any shape, a correction method that approximates the conditions is selected from the shape based on the position of the cavity and runner, the properties of the resin, and the molding conditions, and the target parameters are set.

[0039] Furthermore, the process of obtaining multiple correction methods involves acquiring sensitivity, an index indicating the magnitude of the difference between the analysis results and the measured values ​​of the resin molded product, based on the analysis results of the flow analysis and the measured values ​​of the resin molded product, and then acquiring correction methods based on sensitivity. Sensitivity is an index that indicates the direction of improvement of parameters to make the value of the objective function based on the design target value a predetermined value. Sensitivity is acquired as follows: First, a forward analysis is performed on the initial analysis conditions. Then, an objective function is set derived from the difference between the results of the forward analysis and the design target value. The sensitivity of the design parameters that minimize or maximize the objective function is determined by inverse analysis. Sensitivity can also be said to be the degree of influence of changes in the analysis conditions in the flow analysis on the design target value.

[0040] In transient problems where physical quantities depend on time, sensitivity analysis may be performed at specified time steps.

[0041] Furthermore, the process of performing resin flow analysis on molded products of arbitrary shapes involves using a correction method to set at least one of the following parameters as the target parameters for correction in the flow analysis: resin flow characteristics, resin physical properties, and warpage deformation parameters. Resin flow characteristics include, for example, MFR, MVR, melt viscosity, flow length, melting point, glass transition temperature, and flow length measurement results using a spiral flow mold. Resin physical properties include, for example, density, specific heat, thermal conductivity, elastic modulus, Poisson's ratio, coefficient of linear expansion, PVT characteristics, molding shrinkage rate, and reinforcing material properties. Warpage deformation parameters include, for example, parameters for correcting shrinkage strain, stiffness, mold constraint effect, filler orientation, nozzle boundary conditions (temperature and pressure), stress relaxation, heat transfer coefficient adjustment, and shrinkage initiation determination. The target parameters may be the values ​​of the resin's flow characteristics, physical properties, and warpage deformation parameters themselves, or they may be based on the values ​​of the resin's flow characteristics, physical properties, and warpage deformation parameters as described above. Furthermore, the target parameters are not limited to those exemplified above.

[0042] Furthermore, when optimizing parameters, the parameters may be optimized based on one type of analysis result and its corresponding measurement result (actual value), or the parameters may be optimized so that multiple types of analysis results and their corresponding measurement results (actual values) match. For example, in flow analysis, mold cooling analysis is performed, filling analysis is performed, and holding pressure cooling analysis, shrinkage warpage analysis, and fiber orientation analysis are performed in parallel. In this case, the parameters may be determined simultaneously so that multiple analysis results and measurement results match.

[0043] Here, as an example of a molded product shape, we will describe the case of a box-shaped model.

[0044] In the example shown in Figure 3, the box-shaped molded product is formed by injecting resin from the bottom. The filling pattern is as shown in Figure 3. In the case of this box-shaped model, as shown in Figure 4, the sides of the box deform by curving inward. Note that the amount of deformation is shown with exaggeration compared to the actual value (magnified several tens of times).

[0045] Furthermore, evaluation positions are set to assess the amount of inward tilt of the box-shaped model. These evaluation positions are set, for example, near the center of each side of the box-shaped model, as shown in Figure 5. At the set evaluation positions, the analysis results and measured values ​​are compared to determine the difference in inward tilt (warp). In the example in Figure 5, sensitivity analysis is performed by calculating the difference between the analysis results and measured values ​​at four locations. Here, this technology can reproduce the overall deformation result with greater accuracy if sensitivity analysis is performed based on information about the difference between the analysis results and measured values ​​at as many measurement points as possible. Therefore, it is preferable to perform sensitivity analysis using the results of displacement measurements at many measurement points across the entire area using a 3D measuring instrument. In the example in Figure 5, the number of measurement points has been deliberately reduced to simplify the explanation.

[0046] Furthermore, warp deformation is compared between measured and analyzed values ​​by correcting the analytical values ​​based on the measured values ​​so that the analytical results show good agreement with the measured values. As shown in Figure 6, a forced displacement, which is the difference between the measured and analyzed values, is applied, and a sensitivity analysis is performed. This allows the sensitivity distribution to be determined. Locations with high sensitivity values ​​indicate areas where improvement (correction) is necessary to compensate for the difference between the measured and analyzed values. Based on this sensitivity information, the strain distribution of the original analysis result is corrected according to the magnitude of the sensitivity value. Note that the sensitivity value includes positive, 0, and negative values. The strain is increased or decreased according to the magnitude of the sensitivity. For example, warp analysis is performed by applying a correction to the shrinkage strain distribution of the original analysis result, taking the sensitivity distribution into account. Then, the results of the warp analysis are checked, and the analysis is repeated until the analysis result falls within the threshold.

[0047] As shown in Figure 7, the original shrinkage strain distribution is improved after correction. Here, the distribution and amount of shrinkage strain between the corrected analysis results and the original analysis results represent the location and extent of correction to make the original analysis results match the measured values. For example, in the case of a box-shaped model, the inside of the box has the characteristic of easily accumulating heat within the mold, and the correction method can often be used similarly regardless of the size of the box. Therefore, by looking at the strain distribution required for correction, it is possible to parameterize the content to the extent that it can be generalized. In terms of the parameterization method, the corrected strain is divided into improvement direction groups of the original strain based on information such as distance from the gate, wall thickness, core side or cavity side, and resin flow velocity vector. Then, the parameterized method is applied to the flow analysis of the new model and the analysis is performed.

[0048] As shown in Figure 12, in the example of evaluating the roundness of a cylindrical molded product, the parameters are corrected based on the measured value and the analysis result before correction so that the analysis result approaches the measured value.

[0049] (Extension parameter acquisition process) Referring to Figure 8, the process of obtaining extended parameters (correction methods) to correct the conditions when performing fluid analysis will be explained. This process is performed by computer 1 (processor 2).

[0050] In step S1 of Figure 8, an injection molding simulation is performed, and original data of the analysis results (warpage deformation results) is obtained. In step S2, the measured values ​​at the evaluation position are compared with the values ​​from the analysis results.

[0051] In step S3, it is determined whether the difference between the measured value at the evaluation location and the analysis result value exceeds a predetermined threshold. If there is a difference, the process proceeds to step S4. If there is no difference (i.e., it is smaller than the predetermined threshold), the process of acquiring the extended parameters (correction method) is terminated.

[0052] In step S4, the difference in displacement between the analysis result value and the measured value (forced displacement) is determined at each evaluation position. In step S5, sensitivity analysis is performed using the physical property distribution of the original data from the analysis result and the forced displacement to determine the sensitivity distribution.

[0053] In step S6, the corrected strain distribution is updated using the sensitivity distribution to match the measured values ​​in the analysis. The corrected strain distribution is updated at each location by determining the corrected shrinkage strain ε. In step S7, the coefficient α required for the warp deformation to be equal to the measured values ​​is determined using the original material property data of the analysis results and the corrected shrinkage strain. Specifically, an appropriate coefficient α is determined by repeatedly performing the warp analysis.

[0054] In step S8, the corrected shrinkage strain is converted into extended parameters (correction methods) based on a rule base. The rule base is a combination of target parameters used to universally represent the position of each element of the product shape in the product model. For example, the rule base is a combination of expressions such as the location where the flow length is Xa and the wall thickness is Ya. In step S9, the extended parameters (correction methods) are stored in the storage unit 3. After that, the process of acquiring the extended parameters (correction methods) is completed.

[0055] (Analysis processing using extended parameters) Referring to Figure 9, the analysis process using extended parameters (correction methods) to correct the conditions when performing fluid analysis will be explained. This process is executed by computer 1 (processor 2).

[0056] In step S11 of Figure 9, the simulation is started. In step S12, the user is prompted to choose whether or not to use the previously acquired and stored extended parameters (correction method).

[0057] In step S13, it is determined whether or not to use extended parameters. If extended parameters are to be used, the process proceeds to step S14; otherwise, the process proceeds to step S16. In step S14, the system accepts the selection of extended parameters (correction methods) to be used from a registered list containing multiple extended parameters (correction methods). Alternatively, extended parameters (correction methods) to be used are automatically selected based on the similarity of the feature quantities of the molded product's shape.

[0058] In step S15, after the calculation of the original shrinkage strain from the analysis results is completed, the shrinkage strain is corrected considering the extended parameters (correction method). Then, in step S16, the warp analysis is performed. After that, the analysis process using the extended parameters (correction method) is completed.

[0059] (Filling pattern analysis process) The filling pattern analysis process will be explained with reference to Figures 10 and 11. This process is performed by computer 1 (processor 2). In the filling pattern (flow pattern) analysis process, the difference between the analysis results and the measured values ​​is compared, and the flow pattern (flow method) is adjusted using adjustment parameters so that the two values ​​match. This obtains a correction method for filling pattern analysis.

[0060] In the model shown in Figure 11, resin flows in from the gate, travels through the mold along the trace line (streamline trajectory), and reaches the resin destination. Generally, the melt viscosity data of resin used in injection molding analysis is often obtained by applying the value measured by a capillary rheometer (measuring instrument) to a viscosity model equation and using it during the analysis. However, it is known that melt viscosity varies depending on the measurement method, and unlike material properties, there is no single value that is strictly determined for a material; it is a data value with a certain range that changes depending on the measurement method. Therefore, the inability to reproduce phenomena such as edge flow may be due to phenomena occurring that cannot be represented by existing viscosity model equations.

[0061] Edge flow is a phenomenon in which the edges of a molded product flow ahead of the molded parts during injection molding, and can cause defects in appearance. Edge flow occurs when the shear-heating layer in the runner flows into the cavity, causing the high-temperature layer at the edges to thicken due to volume conservation. The degree to which edge flow occurs is influenced by the physical properties (temperature dependence of viscosity) of the resin material (e.g., PP, PMMA). For example, resin materials like PMMA, where the viscosity value with respect to shear rate changes with temperature, are more prone to edge flow than resin materials like PP, where the viscosity value with respect to shear rate does not change much with temperature.

[0062] Therefore, by acquiring a correction method according to the resin material and using the acquired correction method to adjust the viscosity model of the flow conductance on the trace line flowing around the edge, or the resin data around that area, it is possible to accurately reproduce the edge flow phenomenon through simulation.

[0063] In step S21 of Figure 10, an injection molding simulation is performed and analysis results (filling pattern) are obtained. In step S22, the measured results (short shots) are compared with the analysis results, and the difference in flow at each resin arrival point is calculated. Here, since it is not possible to accurately grasp the intermediate state when actually filling with resin, the amount of resin to be filled is intentionally reduced (creating a short shot state), and the resin is filled so that it stops at an intermediate point, and the measured results are obtained.

[0064] In step S22, the analysis results are compared with the measured results to improve the difference in flow patterns. Alternatively, a screen can be provided where the user can input their assumed flow pattern, and the analysis calculations can be performed using the difference between that pattern and the actual flow pattern. In this case, the screen where the user inputs their assumed flow pattern would be, for example, a screen for setting the order and arrival times of the resin at each node. This allows the user to define the flow pattern, making it possible to perform calculations using the difference.

[0065] In step S23, it is determined whether the difference between the measured value and the analyzed value exceeds a predetermined threshold. If there is a difference, the process proceeds to step S24. If there is no difference (i.e., the difference is smaller than the predetermined threshold), the filling pattern analysis process is terminated.

[0066] In step S24, the streamline trajectory (trace line) from the resin arrival point to the gate, where differences in flow are observed, is calculated. Here, the trace line is a visualization of the path taken by the molten resin flowing from the gate to the resin arrival point.

[0067] In step S25, information on the elements (nodes) that make up each trace line and their position within the analysis model are obtained. Note that trace lines may be calculated for all constituent nodes and used as the calculation area, or, to reduce the computational load, only areas where significant differences in flow patterns are observed may be used as the calculation area. Furthermore, the position information within the model is obtained based, for example, on the distance from the edge (end), wall thickness information, and branching points (rib sections).

[0068] In step S26, the fluid conductance calculation formula and resin data on each trace line are modified. Then, the process returns to step S21.

[0069] (Effects of this embodiment) The effects of this embodiment will now be explained.

[0070] In this embodiment, as described above, multiple correction methods are acquired, including the parameters to be corrected and the correction values ​​in the flow analysis, for correcting the analysis results of the flow analysis to match the measured values. The acquired correction methods are then used to perform a flow analysis of the resin of a molded product of any shape. This allows the target parameters to be corrected according to the shape of the molded product and the resin flow analysis to be performed, thereby enabling accurate flow analysis of the resin of the molded product according to its shape.

[0071] Furthermore, in this embodiment, as described above, the step of performing resin flow analysis on a molded product of any shape includes setting target parameters at a predetermined position on the molded product of any shape using a correction method and then performing the analysis process. This makes it possible to perform resin flow analysis on a molded product of any shape by correcting the target parameters at a predetermined position where the acquired correction method state is similar, thus making it easy to correct and set the target parameters for resin flow analysis on a molded product of any shape.

[0072] Furthermore, in this embodiment, as described above, the step of performing resin flow analysis on a molded product of any shape includes determining a predetermined position for flow analysis based on at least one of the following: resin flow length, thickness of the molded product, determination of core-side or cavity-side region in the mold, anisotropic shrinkage, distance from the end of the molded product, distance from the nozzle, mold temperature variation, rib portion of the molded product, boss portion of the molded product, position relative to the cooling water pipe, position relative to the ejector pin, and position relative to the parting line surface, and then performing analysis processing using a correction method. This makes it possible to easily determine a predetermined position where the resin flow state is common based on at least one of the following: resin flow length, thickness of the molded product, determination of core-side or cavity-side region in the mold, anisotropic shrinkage, distance from the end of the molded product, distance from the nozzle, mold temperature variation, rib portion of the molded product, boss portion of the molded product, position relative to the cooling water pipe, position relative to the ejector pin, and position relative to the parting line surface.

[0073] Furthermore, in this embodiment, as described above, the step of acquiring multiple correction methods involves acquiring sensitivity as an index indicating the magnitude of the difference between the analysis results and the measured values ​​of the resin molded product, based on the analysis results of the flow analysis and the measured values ​​of the resin molded product, and then acquiring a correction method based on the sensitivity. This makes it possible to correct the target parameter at positions where the sensitivity, which is an index indicating the difference between the analysis results and the measured values, is large, so that the analysis results of the flow analysis can be easily brought closer to the measured values.

[0074] Furthermore, in this embodiment, as described above, the step of performing a resin flow analysis of a molded product of any shape is performed by using a correction method to set at least one of the following as parameters to be corrected in the flow analysis: the resin flow characteristics, the resin physical properties, and the warpage deformation parameters, and then performing the analysis. As a result, the resin flow characteristics, the resin physical properties, or the warpage deformation parameters are corrected as target parameters, and the resin flow analysis of the molded product can be performed with high accuracy according to the shape of the molded product.

[0075] (modified version) It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims rather than by the description of the embodiments above, and further includes all modifications (exceptions) within the meaning and scope equivalent to the claims.

[0076] For example, in the above embodiment, for the sake of explanation, a flow-driven flowchart was used to describe the computer's processing operations in a sequential manner according to the processing flow, but the present invention is not limited thereto. In the present invention, the computer's processing operations may be performed by event-driven processing, where processing is performed on an event-by-event basis. In this case, it may be performed entirely by event-driven processing, or a combination of event-driven and flow-driven processing may be used.

[0077] Furthermore, while the above embodiment shows an example of a configuration in which sensitivity is obtained as an index indicating the magnitude of the difference between the analysis result and the measured value, and a correction method is obtained based on the sensitivity, the present invention is not limited to this. In the present invention, a correction method may be obtained without obtaining sensitivity. For example, the difference between the analysis result and the measured value may be checked while changing the parameter value, and a correction method may be obtained by repeatedly performing calculations to reduce the difference. [Explanation of Symbols]

[0078] 1 Computer 3a Program 7. Recording media

Claims

1. The process involves performing a flow analysis of the resin during resin molding, The process involves obtaining a sensitivity distribution as an indicator of the magnitude of the difference between the analysis results and the measured values ​​of the resin molded product, by performing a forward analysis on the analysis conditions based on the analysis results of the flow analysis and the measured values, setting an objective function from the difference between the results of the forward analysis and the design target value, and obtaining a sensitivity distribution as an indicator of the magnitude of the difference between the analysis results and the measured values ​​by obtaining a correction amount that adjusts the analysis results of the flow analysis to match the measured values, thereby obtaining multiple correction methods including the parameters to be corrected and correction values ​​in the flow analysis, by increasing or decreasing the correction amount according to the magnitude of the sensitivity of the sensitivity distribution. A resin molding analysis method comprising the steps of performing a resin flow analysis of a molded product of arbitrary shape by setting target parameters at a predetermined position of a molded product of arbitrary shape using a correction method with similar conditions among a plurality of acquired correction methods, and performing an analysis process.

2. The resin molding analysis method according to claim 1, wherein the step of performing a resin flow analysis of a molded product of any shape includes determining the predetermined position for the flow analysis based on at least one of the following for a molded product of any shape: the flow length of the resin, the wall thickness of the molded product, the determination of the core-side or cavity-side region in the mold, anisotropic shrinkage, the distance from the end of the molded product, the distance from the nozzle, the mold temperature variation, the rib portion of the molded product, the boss portion of the molded product, the position relative to the cooling water pipe, the position relative to the ejector pin, and the position relative to the parting line surface, and performing the analysis process using the correction method.

3. The resin molding analysis method according to claim 1 or 2, wherein the step of performing a flow analysis of a molded product of any shape is to use the correction method to set at least one of the following as parameters to be corrected in the flow analysis: the flow characteristics of the resin, the physical properties of the resin, and the parameters for warping deformation.

4. A program for causing a computer to execute the resin molding analysis method described in claim 1 or 2.

5. A recording medium on which the program described in claim 4 is recorded and which is readable by a computer.

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