Evaluation device, evaluation method, and evaluation program

Abstract

To accurately evaluate an orientation state of fillers at a vicinity of a surface of a molded article.SOLUTION: An evaluation device 1; sets a discharge condition of fillers 7 when discharging a resin that contains the fillers 7 into a resin flow field 5; analyzes a behavior of each of fillers 7 over a period from start of filling to end of filling of the resin using the set discharge condition of the fillers 7 and resin flow field data of the resin flow field 5; and evaluates an orientation state of the fillers 7 contained at a vicinity of a surface of a molded article using the analysis result of the behavior.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an evaluation device, an evaluation method, and an evaluation program. [Background technology]

[0002] In resin molding, adding various fillers to resins can impart various effects to molded products. For example, using metallic particles as fillers can impart a metallic luster to molded products without painting.

[0003] Patent Document 1 discloses a flow analysis method in which the resin flow field is determined by resin flow analysis, multiple virtual particles are generated on the weld lines that occur at the contact points where the flowing resins come into contact, the movement paths of the virtual particles are determined, and the movement distance is calculated to determine the penetration distance of one flowing resin into another flowing resin, and the position where unevenness will occur on the surface of the molded product is predicted from the penetration distance.

[0004] Non-Patent Document 1 discloses a technology for predicting the appearance quality of resin molded products containing metallic particles, using the analysis functions of commercially available resin flow analysis software, in order to understand the occurrence of color unevenness, which is a problem in metallic molding that imparts a metallic luster to molded products. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-343575 [Non-patent literature]

[0006] [Non-Patent Document 1] Takashi Suda, Hiroki Kuroiwa, Tomoyuki Iwasawa, Yoshio Fukushima, "Research on Prototype-less Metallic Molding Using Resin Flow Analysis," Gunma Prefectural Industrial Technology Center Research Report, 2013 Summary of the Invention [Problem to be solved by the invention]

[0007] If the orientation of the filler is locally disturbed on the surface of a molded product, the gloss will be different from that of other areas, which may be considered to be a poor appearance. In order to design products that prevent poor appearance, it is effective to predict the orientation of the filler near the surface of the molded product in advance.

[0008] In injection molding, filler particles located near the leading edge of the resin flow move to the surface of the molded product due to the fountain flow, and then, due to the cooling effect of the mold for the molded product, the solidification of the resin located near the surface of the molded product progresses, and the movement of the filler also stops.

[0009] Therefore, in order to accurately predict the orientation state of the filler near the surface of the molded product, it is important to capture the entire process of filler behavior from when the filler is released into the mold until it stops moving.

[0010] The behavior of fillers in resin is expressed by translational motion (also called "movement") and rotational motion. However, Patent Document 1 focuses only on the translational motion of virtual particles to predict the location of irregularities on the surface of a molded product. In other words, Patent Document 1 predicts the location of irregularities on the surface of a molded product without considering the rotational motion of virtual particles. Therefore, the flow analysis method disclosed in Patent Document 1 cannot accurately predict filler orientation or evaluate the filler orientation state obtained from the filler orientation prediction.

[0011] Furthermore, the commercially available resin flow analysis software used in Non-Patent Document 1 is equipped with a filler orientation analysis function, and the color intensity of the molded product surface is calculated using the obtained filler orientation analysis results, which can then be used to predict the appearance quality of the metallic particle-containing resin molded product. However, because commercially available resin flow analysis software analyzes the filler orientation in units of pre-defined regions (also called "computational meshes") for the molded product, it is unable to predict the filler orientation state with as much accuracy as when analyzing the movement of each filler. Therefore, the accuracy of the evaluation of the filler orientation state predicted from the filler orientation state is also inferior to when analyzing the movement of each filler.

[0012] The present invention aims to provide an evaluation device, an evaluation method, and an evaluation program that can accurately evaluate the orientation state of fillers near the surface of a molded product, compared to when analyzing the orientation of fillers in each predetermined region. [Means for solving the problem]

[0013] The evaluation device of the first embodiment comprises a condition setting unit that sets the filler release conditions when releasing a resin containing a filler into a resin flow field that models the resin injection space used to manufacture a molded product; a behavior analysis unit that uses the filler release conditions set by the condition setting unit and resin flow field data of the resin flow field obtained by resin flow analysis to analyze the behavior of each of the fillers, representing the movement of the filler at each time in the resin flow field, over a period from the start of filling the resin into the resin flow field to the end of filling; and an orientation evaluation unit that uses the analysis results representing the behavior of the filler obtained by the behavior analysis unit to evaluate the orientation state of the filler contained near the surface of the molded product, in a range from the surface of the molded product to a predetermined depth.

[0014] In the evaluation device of the second aspect, in the evaluation device of the first aspect, the resin flow field data includes the resin filling time at each position in the resin flow field, as well as the flow velocity vector and velocity gradient tensor for each time at each position in the resin flow field, and the behavior analysis unit calculates, for each of the fillers that has reached a tip region that is a region including the flow front of the resin and that has been predetermined as a region where fountain flow is recognized to occur, a gradient vector at the resin filling time at the position of the filler included in the tip region, and uses the gradient vector to correct the flow velocity vector and velocity gradient tensor of the resin flow field at the position of the filler.

[0015] The evaluation device of the third aspect is the evaluation device of the second aspect, wherein the behavior analysis unit corrects the velocity gradient tensor of the resin flow field at the position of the filler using the corrected flow velocity vector of the resin flow field.

[0016] The evaluation device of the fourth aspect is an evaluation device of any one of the first to third aspects, in which the behavior analysis unit completes behavior analysis for the fillers that are included near the surface of the molded product and for which a predetermined period of time has passed, and the orientation evaluation unit evaluates the orientation state of the fillers using each of the fillers for which the behavior analysis unit has completed behavior analysis.

[0017] The evaluation device of the fifth aspect is an evaluation device of any one of the first to fourth aspects, wherein the condition setting unit uses the analysis results of the behavior of each of the fillers arranged near the surface of the molded product, going back in time from the end of filling of the resin to the start of filling, and when the filler arranged near the surface of the molded product reaches a release area predetermined as a release location for the filler in the resin flow field, sets the time and position at which the filler arranged near the surface of the molded product reaches the release area as the release condition for the filler contained in the resin filled into the resin flow field.

[0018] The evaluation device according to the sixth aspect is the evaluation device according to the fifth aspect, wherein the analysis results of the behavior of the filler are obtained by analyzing the filler while focusing only on the translational motion of the filler.

[0019] An evaluation method according to a seventh aspect is a method in which a computer sets filler release conditions when releasing a resin containing a filler into a resin flow field that models the injection space of a resin used in manufacturing a molded product, and uses the set filler release conditions and resin flow field data of the resin flow field obtained by resin flow analysis to analyze the behavior of each of the fillers, representing the movement of the filler at each time in the resin flow field, over a period from the start of filling the resin into the resin flow field to the end of filling, and uses the analysis results representing the behavior of the fillers to evaluate the orientation state of the fillers contained near the surface of the molded product, in a range from the surface to a predetermined depth.

[0020] The evaluation program according to the eighth aspect is a program for causing a computer to execute a process of setting filler release conditions when releasing a resin containing a filler into a resin flow field that models the injection space of a resin used in manufacturing a molded product, analyzing the behavior of each of the fillers, representing the movement of the filler at each time in the resin flow field, for a period from the start of filling the resin into the resin flow field to the end of filling, using the set filler release conditions and resin flow field data of the resin flow field obtained by resin flow analysis, and evaluating the orientation state of the filler contained near the surface of the molded product, in a range from the surface to a predetermined depth, using the analysis results representing the behavior of the filler. [Effects of the Invention]

[0021] According to the present invention, the orientation state of the filler in the vicinity of the surface of the molded article can be evaluated with higher accuracy than when the orientation of the filler is analyzed for each predetermined region. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 2 illustrates an example of a functional configuration of an evaluation device. [Figure 2] FIG. 2 is a diagram illustrating an example of the configuration of a main part of an electrical system in an evaluation device. [Figure 3] 1A and 1B are diagrams illustrating examples of the shape of a flat plate. [Figure 4] 10 is a flowchart showing an example of the flow of an evaluation process. [Figure 5] FIG. 2 is a diagram illustrating the orientation angle between the flat plates and the filler. [Figure 6] FIG. 10 is a diagram illustrating an example of an analysis process of filler behavior using inverse time analysis. [Figure 7] FIG. 10 is a diagram showing how filler diffuses through a resin flow field. [Figure 8] FIG. 10 is a cross-sectional view of a resin flow field showing the behavior of a filler in a case where the resin flow field data is corrected but inverse time analysis is not performed. [Figure 9] FIG. 10 is a cross-sectional view of a resin flow field showing the behavior of a filler in a case where neither correction of resin flow field data nor inverse time analysis is performed. [Figure 10] FIG. 10 is a distribution diagram showing an example of the distribution of the average orientation angle of the filler in the case where the resin flow field data is corrected but the inverse time analysis is not performed. [Figure 11] FIG. 1 is a distribution diagram showing an example of the distribution of the average orientation angle of the filler obtained by the conventional technique. [Figure 12] FIG. 10 is a diagram showing an example of an analysis of filler behavior in a case where both correction of resin flow field data and inverse time analysis are performed. [Figure 13] FIG. 10 is a distribution diagram showing an example of the distribution of the average orientation angle of the filler in a case where both correction of resin flow field data and inverse time analysis were performed. [Figure 14] FIG. 10 is a diagram showing an example of the calculation time required to evaluate the orientation state of a filler. DETAILED DESCRIPTION OF THE INVENTION

[0023] The present embodiment will be described below with reference to the drawings. Note that the same components and processes are given the same reference numerals throughout the drawings, and redundant description will be omitted.

[0024] FIG. 1 is a diagram showing an example of the functional configuration of an evaluation device 1 that evaluates the orientation state of a filler 7 contained in the vicinity of the surface of a molded product manufactured by injecting a resin containing the filler 7 from a nozzle into a space formed by a mold.

[0025] Filler 7 is a filler that is filled into resin. For example, if it is difficult to meet the quality required by a customer by manufacturing a molded product using only resin, by filling the resin with filler 7, which has properties different from those of resin, it is possible to manufacture a molded product with properties that cannot be obtained with resin alone.

[0026] Filling resin with filler 7 provides a variety of effects, such as suppressing thermal deformation in molded products, reducing deterioration due to ultraviolet rays, enhancing bending strength, and adjusting magnetic properties. Hereinafter, an evaluation device 1 will be described as an example, which evaluates the orientation state of filler 7 when metallic particles are used as filler 7 to impart a metallic luster to the surface of a molded product. While filler 7 can have various shapes, such as needle-like and spherical, a plate-shaped filler 7 will be used as an example for explanation.

[0027] The orientation state of the filler 7 refers to the state of the filler 7 expressed by the position of the filler 7 in the resin and the direction of the surface of the plate-like filler 7.

[0028] The vicinity of the surface of a molded product refers to a range extending from the surface of the molded product toward the interior of the molded product a predetermined distance (referred to as the "proximal distance") in the normal direction of the surface of the molded product. The proximal distance is set depending on, for example, the size of the filler 7 to be filled into the resin and the purpose of filling the filler 7 into the resin. Depending on the context, the vicinity of the surface of a molded product may be expressed as "proximal to the surface of the molded product."

[0029] As shown in FIG. 1, the evaluation device 1 includes functional units of a condition setting unit 2, a behavior analysis unit 4, and an orientation evaluation unit 6.

[0030] In injection molding, a molded product is manufactured by injecting a resin containing filler 7 into a space formed by a mold (called the "injection space"). The condition setting unit 2 sets the release conditions for the filler 7 for each filler 7 when the resin containing filler 7 is injected into a resin flow field 5 that models the injection space of the resin used to manufacture the molded product.

[0031] The discharge conditions of the filler 7 are expressed by the discharge position of the filler 7 when the filler 7 is discharged into the resin flow field 5 and the discharge time when the filler 7 is discharged into the resin flow field 5.

[0032] The behavior analysis unit 4 performs a resin flow analysis on the resin injected into the resin flow field 5 and acquires resin flow field data of the resin flow field 5.

[0033] Furthermore, the behavior analysis unit 4 uses the discharge conditions for the filler 7 set by the condition setting unit 2 and the resin flow field data of the resin flow field 5 obtained by the resin flow analysis to analyze the behavior of each filler 7 contained in the filled resin in the resin flow field 5 at each time point over the period from the start to the end of filling of the resin into the resin flow field 5. The behavior of the filler 7 is the movement of the filler 7 expressed by a combination of the translational motion and rotational motion of the filler 7.

[0034] The orientation evaluation unit 6 uses the analysis results indicating the behavior of the fillers 7 obtained by the behavior analysis unit 4 to evaluate the orientation state of each filler 7 contained near the surface of the molded product manufactured by injecting resin.

[0035] The evaluation device 1 is configured using a computer 10, for example.

[0036] FIG. 2 is a diagram showing an example of the configuration of the main parts of an electrical system in the evaluation device 1 using the computer 10. As shown in FIG.

[0037] 1 , a ROM (Read Only Memory) 12 that stores an evaluation program that causes the computer 10 to function as the evaluation device 1, a RAM (Random Access Memory) 13 that is used as a temporary work area for the CPU 11, a nonvolatile memory 14, and an input / output interface (I / O) 15. The CPU 11, ROM 12, RAM 13, nonvolatile memory 14, and I / O 15 are all connected to each other via a bus 16.

[0038] The nonvolatile memory 14 is an example of a storage device that maintains stored information even if the power supplied to the nonvolatile memory 14 is cut off, and is, for example, a semiconductor memory, but may also be a hard disk. The nonvolatile memory 14 does not necessarily have to be built into the computer 10, and may be a portable storage device that can be attached to and detached from the computer 10, such as a memory card.

[0039] On the other hand, the I / O 15 is connected to, for example, a communication unit 17, an input unit 18, and a display unit 19.

[0040] The communication unit 17 is connected to a communication line (not shown) and is provided with a communication protocol for performing data communication with an external device, such as a file server, connected to the communication line.

[0041] The input unit 18 is a device that receives instructions from the operator of the evaluation device 1 (hereinafter referred to as "user") and notifies the CPU 11, and may be, for example, a button, a touch panel, a keyboard, a pointing device, a mouse, or the like.

[0042] The display unit 19 is a device that displays information processed by the CPU 11, and may be, for example, a liquid crystal display or an organic EL (Electro Luminescence) display.

[0043] The computer 10 may be configured using cloud computing, in which case the computer 10 is remotely controlled from an external terminal via a communication line. Therefore, the input unit 18 and the display unit 19 are not necessarily required components of the computer 10. Also, for example, if the evaluation device 1 is configured on-premise so that the evaluation device 1 does not need to communicate data with an external device, the communication unit 17 is not necessarily required components of the computer 10.

[0044] Next, the operation of the evaluation process in the evaluation device 1 that evaluates the orientation state of the filler 7 contained in the resin filled in the resin flow field 5 will be described in detail.

[0045] Hereinafter, as an example of a molded product, an example of evaluating the orientation state of filler 7 when manufacturing a flat plate 3 as shown in Figure 3 will be described. Flat plate 3 has a length L = 79 mm, a width W = 59 mm, and a thickness H = 2 mm. One of the sides along the width W direction has a protruding gate that serves as a resin injection port, and a circular hole 32 with a diameter of 10 mm is provided in the center. The resin used to manufacture flat plate 3 is polypropylene, the resin injection speed is 30 cc / s, and the mold temperature is 60°C.

[0046] FIG. 4 is a flowchart showing an example of the flow of the evaluation process executed by the CPU 11 of the evaluation device 1 when an instruction to start evaluation is received from the user via the input unit 18.

[0047] An evaluation program that defines the evaluation process is stored in advance in, for example, the ROM 12 of the evaluation device 1. The CPU 11 of the evaluation device 1 reads the evaluation program stored in the ROM 12 and executes the evaluation process.

[0048] First, in step S10, the CPU 11 performs a resin flow analysis on the resin injected from the nozzle, and acquires the resin filling time at each position in the resin flow field 5, which is a model of the resin injection space in the flat plate 3, and the resin flow velocity vector and velocity gradient tensor for each position at each time. A known method is applied to the resin flow analysis, and the CPU 11 acquires the resin filling time at each position in the resin flow field 5, and the resin flow velocity vector and velocity gradient tensor for each position at each time, in units of calculation mesh. The resin filling time at each position in the resin flow field 5, and the resin flow velocity vector and velocity gradient tensor for each position at each time are an example of resin flow field data.

[0049] In step S20, the CPU 11 sets, for each filler 7, a discharge condition for the filler 7 that specifies when and from which position in the resin flow field 5 the filler 7 is discharged. For ease of explanation, the position in the resin flow field 5 at which the filler 7 is discharged is referred to as the "discharge position of the filler 7," and the time at which the filler 7 is discharged is referred to as the "discharge time of the filler 7." The discharge position of the filler 7 and the discharge time of the filler 7 are examples of the discharge conditions for the filler 7.

[0050] For example, the CPU 11 sets a position selected randomly for each filler 7 using a random number or the like within the region of the resin flow field 5 designated in advance by the user as the release position of each filler 7. The CPU 11 also sets the release time of each filler 7 for each filler 7 so that the fillers 7 are released sequentially from the start to the end of filling of the resin into the resin flow field 5.

[0051] In step S30, the CPU 11 uses the resin flow field data acquired in step S10 and the filler 7 release conditions set in step S20 to analyze the behavior of each filler 7 at each time in time series from the start time of filling the resin into the resin flow field 5 to the end time of filling, using a known analysis method.

[0052] After releasing the filler 7 in accordance with the release conditions of the filler 7, the CPU 11 calculates the time change in the behavior of the filler 7 by solving the equation of motion that represents the translational motion and rotational motion of the filler 7 for each filler 7. For example, the Jeffery equation of motion shown in Non-Patent Document 2 is used to analyze the behavior of the filler 7.

[0053] [Non-patent document 2] G.B.Jeffery,Proc.R.Soc.Lond.A,102,p161-179,(1922)

[0054] Note that, in order to calculate the behavior of the filler 7, resin flow field data is required at the position of each filler 7. Therefore, the CPU 11 calculates the resin flow field data for each time at the position of each filler 7 using equation (1).

[0055] [Number 1] V p =V e +L e r, L p =L e ···(1)

[0056] In equation (1), "V p " represents the position p of the filler 7 and the time when the filler 7 reaches the position p, i.e., the flow velocity vector at the arrival time of the filler 7, and "V e " represents the flow velocity vector at the time of arrival of the filler 7 at the center point of the calculation mesh e where the filler 7 is located. p " represents the velocity gradient tensor at the position p of the filler 7 and the time when the filler 7 arrives at the position p, and "L e ” represents the velocity gradient tensor at the arrival time of the filler 7 at the center point of the computational mesh e where the filler 7 is located. That is, L e is V e and the nabla operator ∇. “r” is the vector from the center point of the computational mesh e to the position of the filler 7.

[0057] The resin filled in the resin flow field 5 cools and solidifies when it comes into contact with the wall of the mold, forming a solidified layer along the wall of the mold. The resin filled in the resin flow field 5 later passes through the solidified layer and flows toward the flow front, where it flows from the center of the flow front toward the surface of the flat plate 3 like a fountain. This type of resin flow is called "fountain flow."

[0058] The CPU 11 determines that, among the fillers 7 that have moved into the vicinity of the surface of the flat plate 3 due to the fountain flow, the resin around the fillers 7 has solidified for a predetermined period of time, and terminates the analysis of the behavior of the corresponding fillers 7.

[0059] In step S40, the CPU 11 evaluates the orientation state of the fillers 7 by using each of the fillers 7 present near the surface of the slab 3 and for which the behavior analysis has been completed. This is because the properties imparted to the slab 3 by the fillers 7 are more susceptible to the influence of the fillers 7 present near the surface of the slab 3 than to the influence of the fillers 7 present outside the surface of the slab 3. This tendency is particularly strong for properties of the slab 3 that are recognized by looking at the surface of the slab 3, such as gloss and color.

[0060] The CPU 11 evaluates the orientation state of the filler 7 using the angle (referred to as the "orientation angle") formed between the normal vector (referred to as the "filler normal vector") on the surface of the plate-shaped filler 7 and the normal vector (referred to as the "surface normal vector") on the surface of the flat plate 3 at the position where the filler normal vector intersects with the surface of the flat plate 3 located closest to the surface of the filler 7.

[0061] When the orientation angle is 0 degrees, the face of the filler 7 is arranged so as to face the surface of the flat plate 3, that is, the face of the filler 7 is arranged along the surface of the flat plate 3. When the orientation angle is 90 degrees, the edge of the filler 7, that is, the cross section of the filler 7, is arranged so as to face the surface of the flat plate 3.

[0062] Figure 5 shows the positional relationship between the surface of the flat plate 3 and the filler 7, where Figure 5(A) shows the positional relationship between the surface of the flat plate 3 and the filler 7 when the orientation angle is 0 degrees, and Figure 5(B) shows the positional relationship between the surface of the flat plate 3 and the filler 7 when the orientation angle is 90 degrees.

[0063] When the orientation angle is 0 degrees, the area of ​​the filler 7 projected onto the surface of the flat plate 3 is larger than when the orientation angle is 90 degrees, and therefore a more metallic luster can be imparted to the flat plate 3 than when the orientation angle is 90 degrees. In other words, the smaller the orientation angle of the filler 7, the better the orientation state of the filler 7.

[0064] Therefore, the CPU 11 displays the orientation state of the filler 7 evaluated using the orientation angle of each filler 7 on the display unit 19. Specifically, the CPU 11 displays the orientation state of the filler 7 using, for example, the average orientation angle of the filler 7 or the number of fillers 7 for each orientation angle. This completes the evaluation process shown in FIG. 4.

[0065] As described above, the evaluation device 1 according to this embodiment uses the resin flow field data and the release conditions of the filler 7 to analyze the behavior of each filler 7 at each time in time series from the start time of filling the resin into the resin flow field 5 to the end time of filling, and evaluates the orientation state of the filler 7 contained near the surface of the molded article for each filler 7. Therefore, the evaluation device 1 can evaluate the orientation state of the filler near the surface of the molded article with higher accuracy than when the orientation of the filler is analyzed for each calculation mesh e.

[0066] <Variation 1> In step S30 of the evaluation process shown in FIG. 4, regardless of the position of the filler 7 in the resin flow field 5, the resin flow field data was calculated by equation (1).

[0067] However, in an area where fountain flow is occurring, a resin flow occurs that is different from an area where fountain flow is not occurring. Therefore, when the filler 7 reaches a tip area that is a region including the resin flow front and that is predetermined as an area where the occurrence of fountain flow is recognized, the behavior analysis unit 4 calculates a gradient vector at the position of the filler 7 included in the tip area at the time of resin filling, and corrects the flow velocity vector and velocity gradient tensor of the resin flow field 5 for each time at the position of each filler 7 included in the tip area using the calculated gradient vector.

[0068] Specifically, for the fillers 7 included in the tip region, the CPU 11 calculates resin flow field data for each time at the position of each filler 7 included in the tip region using equation (2) instead of equation (1).

[0069] [Number 2] V p =V ^ e +L ^ e r, L p =L ^ e ···(2)

[0070] In equation (2), V ^ e and L ^ e are the corrected velocity vector and velocity gradient tensor, respectively, and V ^ e is calculated using equation (3).

[0071] [Number 3] V ^ e =|V e |(∇t fill / |∇t fill |) ···(3)

[0072] In equation (3), ∇t fill is the resin filling time t calculated at the center point of the calculation mesh e where the filler 7 is located. fill is the gradient vector of

[0073] L ^ e is V ^ e The gradient of V ^ e and the nabla operator ∇. In other words, the CPU 11 calculates the corrected flow velocity vector V ^ e is used to correct the velocity gradient tensor at the position of each filler 7 included in the tip region.

[0074] In this way, according to the evaluation device 1 of variant example 1, the behavior of the filler 7 is analyzed by correcting the flow velocity vector and velocity gradient tensor of the resin flow field 5 for each time at the position of each filler 7 included in the tip region, so that regardless of the position of the filler 7 in the resin flow field 5, the behavior of the filler 7 can be analyzed more accurately than when the resin flow field data is calculated using equation (1).

[0075] <Variation 2> In step S20 of the evaluation process shown in Figure 4, a release region 9 was randomly selected for each filler 7, i.e., a position within the region of the resin flow field 5 specified by the user as the release location for the filler 7 was set as the release position for each filler 7. However, the released fillers 7 also include fillers 7 that do not reach the vicinity of the surface of the flat plate 3. Because the evaluation device 1 evaluates the orientation state of the fillers 7 using fillers 7 located in the vicinity of the surface of the flat plate 3, whether or not the behavior of fillers 7 that do not reach the vicinity of the surface of the flat plate 3 is analyzed does not affect the evaluation accuracy of the orientation state of the filler 7.

[0076] Therefore, the condition setting unit 2 cooperates with the behavior analysis unit 4 to set the release conditions for the filler 7 only for the filler 7 that reaches the vicinity of the surface of the flat plate 3 .

[0077] 4, the CPU 11 generates a plurality of fillers 7 at a target density near the surface of the flat plate 3. Each filler 7 generated near the surface of the flat plate 3 represents the position of each filler 7 in a state where the resin filling is completed and the resin has solidified.

[0078] Then, the CPU 11 analyzes the behavior of each filler 7 generated near the surface of the plate 3 by tracing back in time from the end of resin filling to the start of filling. This analysis of the behavior of the filler 7 is called "reverse time analysis." Note that the analysis of the behavior of each filler 7 in the reverse time analysis can be performed using Jeffery's equation of motion, similar to the processing in step S30 of the evaluation processing shown in FIG.

[0079] Specifically, the CPU 11 starts the movement of the filler 7 from the time when the filler 7 enters the leading edge region where the occurrence of the fountain flow is recognized.

[0080] 4, the CPU 11 calculated the time change in the behavior of the filler 7 by solving the equation of motion that represents the translational motion and rotational motion of the filler 7 for each filler 7, but in the inverse time analysis, the behavior of each filler 7 is analyzed by solving only the equation of motion that represents the translational motion of the filler 7, without solving the equation of motion that represents the rotational motion of the filler 7. This is because the release conditions for the filler 7 can be set if only the position of the filler 7 in the resin flow field 5 and the arrival time of the filler 7 at that position are known.

[0081] In this way, by analyzing the behavior of each filler 7 by focusing only on the translational motion of the filler 7, the analysis time required for the reverse time analysis can be shortened compared to when the rotational motion of the filler 7 is also analyzed.

[0082] The CPU 11 performs a reverse time analysis and sets the time and position when each filler 7 generated near the surface of the flat plate 3 reaches the release area 9 defined as the release location of the filler 7 in the resin flow field 5 as the release time and release position of the filler 7, respectively.

[0083] Figure 6 is a diagram showing an example of the analysis process of the behavior of the filler 7 using inverse time analysis. The analysis results of the behavior of the filler 7 closer to the start time of resin filling are shown at the bottom of Figure 6. Note that in the example analysis process of Figure 6, only the moving filler 7 is displayed.

[0084] As shown in FIG. 6, the behavior of the filler 7 located in the tip region going back in time and approaching the release region 9 demarcated by the dotted line is analyzed by reverse time analysis.

[0085] Using the analysis results of the behavior of the filler 7 by inverse time analysis, the release conditions for each filler 7 are set, and in the processing of step S30 of the evaluation process shown in Figure 4, the behavior of each filler 7 at each time is analyzed in chronological order using the set release conditions for each filler 7 from the start time of resin filling into the resin flow field 5 to the end time of filling, thereby narrowing down the objects of behavior analysis to fillers 7 that are thought to reach the vicinity of the surface of the flat plate 3.

[0086] Therefore, the evaluation device 1 according to the second modification can analyze the behavior of each filler 7 in a shorter time than the time required to analyze the behavior of the filler 7 in step S30 of the evaluation process shown in FIG.

[0087] <Analysis example> Next, an example of analysis of the behavior of the filler 7 in the evaluation device 1 will be shown. As an example, analysis examples in three analysis cases A1, A2, and B listed in Table 1 will be shown.

[0088] [Table 1]

[0089] Analysis case A1 is an example of analysis in which the resin flow field data in the tip region shown in variant example 1 is corrected in step S30 of the evaluation process shown in Figure 4, and the release conditions for filler 7 are not set using the inverse time analysis shown in variant example 2 in step S20 of the evaluation process shown in Figure 4.

[0090] Analysis case A2 is an example of analysis in which the resin flow field data in the tip region shown in Modification 1 is corrected in step S30 of the evaluation process shown in Fig. 4, and the release conditions for the filler 7 are set by inverse time analysis shown in Modification 2 in step S20 of the evaluation process shown in Fig. 4. In analysis case A2, the filler 7 was generated near the surface of the flat plate 3 with the neighborhood distance set to 200 μm, and the inverse time analysis was performed.

[0091] Analysis case B is an example of analysis in which the correction of resin flow field data in the tip region as shown in variant example 1 is not performed in step S30 of the evaluation process shown in Figure 4, and the setting of the release conditions of filler 7 by inverse time analysis as shown in variant example 2 is not performed in step S20 of the evaluation process shown in Figure 4.

[0092] The filler 7 used for the behavior analysis was a plate-like filler 7 expressed as a square having a thickness of 1 μm and a side length of 60 μm.

[0093] For each of analysis cases A1, A2, and B, if the evaluation process shown in Figure 4 is performed according to the conditions shown in Table 1, the behavior of the filler 7 in the resin flow field 5 corresponding to the flat plate 3 will be analyzed. As an example, Figure 7 shows an analysis example of the behavior of the filler 7 in analysis case A1. Figure 7 shows how the filler 7 released from the release region 9 diffuses through the resin flow field 5. Note that Figure 7 only shows the moving filler 7.

[0094] [Comparison between analysis case A1 and analysis case B] The analysis results of analysis case A1 and analysis case B are compared to verify the effect of correcting the resin flow field data in the tip region, as shown in modified example 1.

[0095] FIG. 8 is a cross-sectional view 20 of the resin flow field 5 showing the behavior of the filler 7 in the vicinity region including the resin flow front analyzed in analysis case A1.

[0096] FIG. 9 is a cross-sectional view 20 of the resin flow field 5, which shows the behavior of the filler 7 in the vicinity of the resin flow front analyzed in analysis case B.

[0097] 8 and 9, arrows 24 indicate the direction of resin flow at the position of each filler 7. Furthermore, a portion 22 indicates the surface (wall surface) of the flat plate 3.

[0098] In Figure 8, it can be seen that the filler 7 moves toward the surface of the flat plate 3 due to the fountain flow. However, in Figure 9, it was not possible to fully analyze the flow of resin due to the fountain flow, and therefore it was not possible to see the filler 7 moving toward the surface of the flat plate 3 as in Figure 8.

[0099] Therefore, it can be said that applying the correction of the resin flow field data in the tip region of the resin shown in variant example 1 to the evaluation process shown in Figure 4 allows for more accurate evaluation of the orientation state of the filler 7 than when variant example 1 is not applied.

[0100] FIG. 10 is a distribution diagram 26 showing an example of the distribution of the average orientation angle of the filler 7 in the flat plate 3, obtained from the analysis results of the behavior of the filler 7 in analysis case A1.

[0101] On the other hand, Figure 11 is a distribution diagram 28 showing an example of the distribution of the average orientation angle of filler 7 in the flat plate 3 in an orientation prediction using commercially available resin flow analysis software. Note that in distribution diagram 28 of Figure 11, the thickness direction component of the orientation tensor of filler 7 is used as an index representing the orientation state of filler 7, and the lower the value of the thickness direction component of the orientation tensor, i.e., the lower the brightness of the area in distribution diagram 28, the closer the average orientation angle of filler 7 is to 90 degrees (also referred to as "larger average orientation angle").

[0102] 10 and 11, a linear region with a larger average orientation angle than other regions can be seen on the right side (downstream side in the resin filling direction) of the circular hole 32. Therefore, it can be seen that the analysis results of the behavior of the filler 7 by analysis case A1 do not contradict the tendency of the experimental results of appearance quality prediction shown in Non-Patent Document 1.

[0103] On the other hand, in distribution diagram 28, a wide area near the periphery of plate 3 is observed where the average orientation angle is larger than in other areas. This is thought to be due in part to the inability to adequately represent the actual resin flow due to fountain flow. In distribution diagram 26, there is not as much of a region near the periphery of plate 3 as in distribution diagram 28 where the average orientation angle is larger than in other areas.

[0104] Therefore, it can be seen that the evaluation device 1 that executed analysis case A1 analyzed the orientation state of the filler 7 more accurately than the analysis function of commercially available resin flow analysis software. In other words, it can be seen that the evaluation device 1 according to this embodiment can evaluate the orientation state of the filler 7 near the surface of the molded product with higher accuracy than when analyzing the orientation of the filler 7 for each calculation mesh.

[0105] [Comparison between analysis case A1 and analysis case A2] Next, the analysis results of analysis case A1 and analysis case A2 are compared to verify the effect of setting the release conditions of the filler 7 by reverse time analysis, as shown in Modification 2.

[0106] Fig. 12 is a diagram showing an example of analysis of the behavior of the filler 7 in analysis case A2. The example of analysis in Fig. 12 is an analysis result obtained at the same time as the example of analysis of the behavior of the filler 7 in analysis case A1 shown in Fig. 7. Note that Fig. 12 shows only the moving filler 7.

[0107] Comparing the analysis results shown in Fig. 7 and Fig. 12, the filler 7 is widely distributed in the resin flow field 5 in Fig. 7, whereas in Fig. 12 the filler 7 is distributed only in a specific area that is narrower than that in Fig. 7. This is because the analysis results shown in Fig. 12 performed a time-inverse analysis, and analyzed the behavior of the filler 7 by focusing only on the filler 7 that is thought to reach the vicinity of the surface of the plate 3.

[0108] Specifically, in the analysis results shown in Fig. 7, of the 800,000 fillers 7 whose behavior was analyzed, only 20% of the fillers 7 reached the vicinity of the surface of the flat plate 3 and were used to evaluate the orientation state. In contrast, in the analysis results shown in Fig. 12, of the fillers 7 whose behavior was analyzed, 95% of the fillers 7 were used to evaluate the orientation state.

[0109] FIG. 13 is a distribution diagram 30 showing an example of the distribution of the average orientation angle of the filler 7 in the flat plate 3, obtained from the analysis results of the behavior of the filler 7 in analysis case A2.

[0110] In analysis case A2, the number of fillers 7 whose behavior was analyzed was smaller than in analysis case A1, but it can be seen that an orientation state showing a similar tendency to the distribution diagram 26 of the average orientation angle of filler 7 by analysis case A1 shown in Figure 10 was obtained.

[0111] Next, the calculation time for analysis case A1 and the calculation time for analysis case A2 will be examined.

[0112] 14 shows an example of measured values ​​of the calculation time in analysis case A1 and the calculation time in analysis case A2. In order to make the preconditions for comparison the same, the calculation time required for analysis was measured under conditions in which the number of fillers 7 used to evaluate the orientation state of the fillers 7 was the same in both cases.

[0113] 14, the calculation time required for the behavior analysis of the filler 7 in analysis case A1 was approximately 45 minutes, and the calculation time required for the behavior analysis of the filler 7 in analysis case A2 was approximately 9 minutes and 10 seconds. In other words, it can be seen that the calculation time required for the behavior analysis of the filler 7 in analysis case A2 is approximately 4.9 times faster than the same calculation time in analysis case A1.

[0114] Note that analysis case A2 requires calculation time required to set the release conditions of filler 7 using inverse time analysis. However, even if the calculation time required to set the release conditions of filler 7 is added to the calculation time required to analyze the behavior of filler 7 in analysis case A2, the total calculation time is only about 24 minutes and 30 seconds. Therefore, even when comparing the total calculation time, the calculation time in analysis case A2 is shorter than the calculation time in analysis case A1, and is found to be about 1.8 times faster.

[0115] Although the present invention has been described above using the embodiments, the present invention is not limited to the scope of the embodiments. Various modifications or improvements can be made to the embodiments without departing from the spirit of the present invention, and such modifications or improvements are also included in the technical scope of the present invention. For example, the order of processing may be changed without departing from the spirit of the present invention.

[0116] In the embodiment, an example has been described in which the evaluation process in the evaluation device 1 is realized by software, but the process equivalent to the flowchart shown in Fig. 4 may be implemented in, for example, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a PLD (Programmable Logic Device) and processed by hardware. In this case, the processing speed can be increased compared to when the evaluation process is realized by software.

[0117] In this way, the CPU 11 of the evaluation device 1 may be replaced with a dedicated processor specialized for specific processing, such as an ASIC, FPGA, PLD, GPU (Graphics Processing Unit), or FPU (Floating Point Unit).

[0118] Furthermore, the operation of the CPU 11 of the evaluation device 1 in the embodiment may be realized by one CPU 11 or by multiple CPUs 11. Furthermore, the operation of the CPU 11 of the evaluation device 1 in the embodiment may be realized by cooperation of CPUs 11 in computers 10 located at physically separate locations.

[0119] In the above-described embodiment, the evaluation program read by the CPU 11 of the evaluation device 1 is installed in the ROM 12, but the present invention is not limited to this. The evaluation program according to this embodiment can also be provided in a form recorded on a storage medium readable by the computer 10. For example, the evaluation program may be provided in a form recorded on an optical disc such as a CD (Compact Disc)-ROM or a DVD (Digital Versatile Disc)-ROM. The evaluation program may also be provided in a form recorded on a portable semiconductor memory such as a USB (Universal Serial Bus) memory or a memory card. The ROM 12, the nonvolatile memory 14, a CD-ROM, a DVD-ROM, a USB, and a memory card are examples of non-transitory storage media.

[0120] Furthermore, the evaluation device 1 may download the evaluation program from an external device connected to a communication line. In this case, the CPU 11 of the evaluation device 1 reads the evaluation program downloaded from the external device and executes the evaluation process.

[0121] In addition, the following supplementary notes are disclosed regarding the above-described embodiment.

[0122] (Additional note 1) Memory and at least one processor coupled to said memory; Including, The processor: setting a discharge condition for a filler when discharging a resin containing the filler into a resin flow field that is a model of a resin injection space used in the manufacture of a molded product; Using the set filler release conditions and resin flow field data of the resin flow field obtained by resin flow analysis, analyze the behavior of each of the fillers, which represents the movement of the filler at each time in the resin flow field, over a period from the start of filling the resin into the resin flow field to the end of filling; Using the analysis results showing the behavior of the filler, the orientation state of the filler contained in the vicinity of the surface of the molded article, which is within a range from the surface of the molded article to a predetermined depth, is evaluated. Evaluation equipment.

[0123] (Additional note 2) A non-transitory storage medium storing a program executable by a computer to perform an evaluation process, The evaluation process includes: setting a discharge condition for a filler when discharging a resin containing the filler into a resin flow field that is a model of a resin injection space used in the manufacture of a molded product; Using the set filler release conditions and resin flow field data of the resin flow field obtained by resin flow analysis, analyze the behavior of each of the fillers, which represents the movement of the filler at each time in the resin flow field, over a period from the start of filling the resin into the resin flow field to the end of filling; Using the analysis results showing the behavior of the filler, the orientation state of the filler contained in the vicinity of the surface of the molded article, which is within a range from the surface of the molded article to a predetermined depth, is evaluated. Non-transitory storage medium. [Explanation of symbols]

[0124] 1 Evaluation device 2 Condition setting section 3 flat plate 4. Behavior Analysis Section 5 Resin flow field 6 Orientation evaluation section 7. Filler 9 Emission area 10. Computers 11 CPU 12 ROM 13 RAM 14 Non-volatile memory 15 I / O 16 Bus 17 Communication Unit 18 Input Units 19 Display unit 20 Cross-section of resin flow field 22 (flat) part 24 Arrow 26 Distribution of average orientation angle in analysis case A1 28. Conventional average orientation angle distribution diagram 30 Distribution of average orientation angle in analysis case A2 32 circular hole

Claims

1. a condition setting unit that sets a discharge condition for a filler when a resin containing the filler is discharged into a resin flow field that is a model of an injection space of a resin used in manufacturing a molded product; a behavior analysis unit that analyzes the behavior of each of the fillers, which represents the movement of the filler at each time in the resin flow field, over a period from the start of filling the resin into the resin flow field to the end of filling, using the filler release conditions set by the condition setting unit and resin flow field data of the resin flow field obtained by resin flow analysis; An orientation evaluation unit that evaluates the orientation state of the filler contained in the vicinity of the surface of the molded article, which is within a range from the surface of the molded article to a predetermined depth, using the analysis results indicating the behavior of the filler obtained by the behavior analysis unit; Equipped with The resin flow field data includes a resin filling time at each position in the resin flow field, and a flow velocity vector and a velocity gradient tensor for each time at each position in the resin flow field, The behavior analysis unit calculates a gradient vector at the position of the filler included in the tip region at the time of resin filling for each of the fillers that has reached the tip region, which is a region including the flow front of the resin and is predetermined as a region where the occurrence of fountain flow is recognized, and corrects a flow velocity vector and a velocity gradient tensor of the resin flow field at the position of the filler using the gradient vector. Evaluation equipment.

2. The behavior analysis unit corrects a velocity gradient tensor of the resin flow field at the position of the filler using the corrected flow velocity vector of the resin flow field. The evaluation device according to claim 1 .

3. the behavior analysis unit completes the behavior analysis for the filler that is included in the vicinity of the surface of the molded product and for which a predetermined period of time has elapsed; The orientation evaluation unit evaluates the orientation state of the filler using each of the fillers whose behavior has been analyzed by the behavior analysis unit. The evaluation device according to claim 1 or 2.

4. The condition setting unit uses the analysis results of the behavior of each of the fillers arranged near the surface of the molded product while tracing back in time from the end of filling of the resin to the start of filling, When the filler arranged in the vicinity of the surface of the molded article reaches a release region that is predetermined as a release location of the filler in the resin flow field, the time and position at which the filler arranged in the vicinity of the surface of the molded article reaches the release region are set as release conditions for the filler contained in the resin filling the resin flow field. The evaluation device according to any one of claims 1 to 3.

5. The analysis results of the behavior of the filler were obtained by analyzing only the translational motion of the filler. The evaluation device according to claim 4 .

6. A condition setting unit that sets the discharge conditions of the filler when discharging a resin containing the filler into a resin flow field that models a resin injection space used in manufacturing a molded product; a behavior analysis unit that analyzes the behavior of each of the fillers, which represents the movement of the filler at each time in the resin flow field, over a period from the start of filling the resin into the resin flow field to the end of filling, using the filler release conditions set by the condition setting unit and resin flow field data of the resin flow field obtained by resin flow analysis; An orientation evaluation unit that evaluates the orientation state of the filler contained in the vicinity of the surface of the molded article, which is within a range from the surface of the molded article to a predetermined depth, using the analysis results indicating the behavior of the filler obtained by the behavior analysis unit; Equipped with the behavior analysis unit completes the behavior analysis for the filler that is included in the vicinity of the surface of the molded product and for which a predetermined period of time has elapsed; The orientation evaluation unit evaluates the orientation state of the filler using each of the fillers whose behavior has been analyzed by the behavior analysis unit. Evaluation equipment.

7. A condition setting unit that sets the discharge conditions of the filler when discharging a resin containing the filler into a resin flow field that models an injection space of the resin used in manufacturing a molded product; a behavior analysis unit that analyzes the behavior of each of the fillers, which represents the movement of the filler at each time in the resin flow field, over a period from the start of filling the resin into the resin flow field to the end of filling, using the filler release conditions set by the condition setting unit and resin flow field data of the resin flow field obtained by resin flow analysis; An orientation evaluation unit that evaluates the orientation state of the filler contained in the vicinity of the surface of the molded article, which is within a range from the surface of the molded article to a predetermined depth, using the analysis results indicating the behavior of the filler obtained by the behavior analysis unit; Equipped with The condition setting unit uses the analysis results of the behavior of each of the fillers arranged near the surface of the molded product while tracing back in time from the end of filling of the resin to the start of filling, When the filler arranged in the vicinity of the surface of the molded article reaches a release region that is predetermined as a release location of the filler in the resin flow field, the time and position at which the filler arranged in the vicinity of the surface of the molded article reaches the release region are set as release conditions for the filler contained in the resin filling the resin flow field. Evaluation equipment.

8. The computer setting a discharge condition for a filler when discharging a resin containing the filler into a resin flow field that is a model of a resin injection space used in the manufacture of a molded product; Using the set filler discharge conditions, the resin filling time at each position in the resin flow field obtained by the resin flow analysis, and resin flow field data including the flow velocity vector and velocity gradient tensor for each time at each position in the resin flow field, the behavior of the filler representing the movement of the filler at each time in the resin flow field over a period from the start to the end of filling of the resin into the resin flow field is analyzed, by calculating a gradient vector at the resin filling time at the position of the filler included in the tip region for each of the fillers that has reached a region including the flow front of the resin and that is predetermined as a region where the occurrence of fountain flow is recognized, and correcting the flow velocity vector and velocity gradient tensor of the resin flow field at the position of the filler using the gradient vector; Using the analysis results showing the behavior of the filler, the orientation state of the filler contained in the vicinity of the surface of the molded article, which is within a range from the surface of the molded article to a predetermined depth, is evaluated. Evaluation method.

9. On the computer, setting a discharge condition for a filler when discharging a resin containing the filler into a resin flow field that is a model of a resin injection space used in the manufacture of a molded product; Using the set filler discharge conditions, the resin filling time at each position in the resin flow field obtained by the resin flow analysis, and resin flow field data including the flow velocity vector and velocity gradient tensor for each time at each position in the resin flow field, the behavior of the filler representing the movement of the filler at each time in the resin flow field over a period from the start to the end of filling of the resin into the resin flow field is analyzed, by calculating a gradient vector at the resin filling time at the position of the filler included in the tip region for each of the fillers that has reached a region including the flow front of the resin and that is predetermined as a region where the occurrence of fountain flow is recognized, and correcting the flow velocity vector and velocity gradient tensor of the resin flow field at the position of the filler using the gradient vector; and executing a process for evaluating the orientation state of the filler contained in the vicinity of the surface of the molded article in a range from the surface of the molded article to a predetermined depth using an analysis result showing the behavior of the filler. Evaluation program.

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