JPH01123717A - Method for displaying flow analysis result of molten material in molding - Google Patents

Abstract

PURPOSE:To make it possible to easily judge whether a filling pattern passing through a specified point is proper or not by a method wherein a filling flow chart is made by successively obtaining intersecting points of a normal line drawn from an arbitrarily selected set point on an isochronous line to said isochronous line and an adjacent isochronous line. CONSTITUTION:By taking a gate position (g) as a starting point, through which resin is filled, an arbitrary point A on the first isochronous line t1 is selected so as to connect the position (g) and the point A by a straight line. Next, a normal line l1 is drawn from the point A to the first isochronous line t1 so as to intersect the second isochronous line t2 at the point B. After that, a normal line l2 is drawn from the point B to the second isochronous line t2 so as to intersect the third isochronous line t3 at the point C. As hereafter repeated by similar procedure, for example, normal lines l3-l19 are drawn from points C-S to the third-the nineteenth isochronous lines t3-t19 so as to be connected to one another in order to describe one continuous filling flow chart. As a result, a course of element regions, which are represented by hatching, can be displayed by extracting split elements, through which said described filling flow line passes.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention provides a method for molding a molten material such as a resin with a mold.
It relates to a method for analyzing the optimal molding conditions for molten material to obtain high-quality molded products, and in particular, a display method that allows easy judgment of the suitability of the progress of filling the required molten material into a mold. Regarding.

[Conventional technology]

Conventionally, when performing resin flow analysis (simulation) in a mold in injection molding using resin materials, for example, as shown in Figure 3, the shape model of the molded product is divided into minute elements, and the finite element method and boundary analysis are performed. A commonly used method is to calculate the equation of motion of a fluid, the equation of continuity, the equation of energy, etc. using numerical analysis methods such as the element method, the difference method, and the FAN method.

In such a resin flow analysis method within a mold, the total filling time into the mold is divided into an arbitrary number of parts, as shown in Figure 4, as a method to express the progress of the resin being filled into the mold. death,
An isochronous diagram created by connecting the arrival positions of the resin filled at each time with lines is used.

[Problem that the invention seeks to solve]

However, the conventional resin flow analysis method described above, which expresses the progress of the resin filling the mold using an isochron diagram, does not allow for accurate analysis of whether the filling order is appropriate, that is, the flow of the resin being filled is well-balanced. It is possible to determine whether or not to proceed and to determine whether the final filling position is appropriate.

However, with this method of analyzing resin flow within a mold, molding defects due to flow disturbances and shear heat generation that occur when the resin speed during filling is too high, and molding defects when the resin speed during filling is too low. When molding defects or the like occur at a specific point due to excessive growth of the resulting non-fluidized layer, it is difficult to judge whether or not the setting of the filling rate is the optimum molding condition that can prevent this. In particular, using only the above-mentioned isochronous diagram, it is difficult to judge whether inputting a speed profile in programmed injection in which the filling speed is set in multiple stages is effective in improving molding defects that occur at specific points.

Therefore, the purpose of the present invention is to analyze the flow of molten material in a required mold by applying the isochronous diagram of the conventional mold filling pattern to determine whether the progress of the molten material filling the mold is appropriate. An object of the present invention is to provide a method for displaying flow analysis results in mold molding of molten material, which allows easy determination of flow analysis results.

[Means for solving problems]

The method of displaying the flow analysis results in mold forming of molten materials according to the present invention is to divide the molded product shape model into minute elements and use numerical analysis methods including the finite element method, boundary element method, finite difference method, FAN method, etc. In the system used to analyze the flow of molten material in a mold, the total time required for the process of filling the molten material into the mold is divided into arbitrary numbers, and the filling progress at each time is plotted as an isochron diagram. Express it as death,
The present invention is characterized in that the operation of drawing a normal line to the isochronous line from this set point is sequentially repeated, and a filling flow diagram is created and displayed using the set point for each isochronous line and the normal line connecting them.

In the method for displaying the flow analysis results described above, it is preferable to designate elements that overlap with a part of the filling flow line for the divided minute elements of the molded product-shape model and to identify and display these areas.

[Effect]

According to the method for displaying flow analysis results in mold forming of molten material according to the present invention, an isochronous diagram representing the progress of filling the molten material into the mold is used, and arbitrary selection settings on the isochronous diagram are used. By drawing a normal line from a point and sequentially finding the points of intersection with adjacent isochronous lines to create a filling flow diagram, it is possible to express a fixed reference line for the isochronous diagram, and each of these can be used as an element. By displaying the divided corresponding element areas, it is possible to easily judge whether or not the progress of filling the mold with the molten material is appropriate. Therefore, in this case, by specifying elements that overlap with part of the filling flow line described above for the divided elements and identifying and displaying these element areas, it is possible to check whether the progress of the molten material filling into the mold is appropriate or not. Judgment becomes easy.

〔Example〕

Next, an embodiment of a method for displaying flow analysis results in mold molding of molten material according to the present invention will be described in detail below with reference to the accompanying drawings.

In the present invention, the procedure for analyzing the resin flow within a mold for a shape model of a predetermined molded product is the same as that of the conventional Cimini-Resilane method. That is, as shown in Figure 3,
In order to analyze the resin flow inside the mold, the shape model of the molded product is divided into elements (triangular elements are used in the illustrated example, but quadrilateral elements may also be used), and the finite element method is applied. The position and number of gates are set for this shape model of the molded product, and launches are provided as necessary to complete the setting of the mold side shape for flow analysis. Here, after selecting the resin to be used and inputting the resin physical property data, enter input conditions such as resin temperature, mold temperature, and filling speed. We move on to the analysis of the pattern, that is, the isochron diagram (see FIG. 4). The procedure up to this point is similar to conventional resin flow analysis within a mold.

Therefore, in this example, the element division display diagram of the molded product shape model shown in FIG.
The isochron diagram as a salt pattern is displayed in an overlapping manner. That is, FIG. 1 shows an embodiment of the display method according to the present invention, and FIG. 2 is an explanatory diagram showing an analysis method for displaying according to the present invention.

Next, the display method of the present invention will be explained based on FIG. First, starting from the gate position g where resin is filled, select an arbitrary point A on the first isochronous line t, and connect the position g and point A with a line. A normal line I11 to the first isochronous line t is drawn starting from t, and its intersection with the second isochronous line t2 is designated as B. Then, a normal line 12 to the second isochronous line t2 starting from the point B
At this time, the third isochronous line t.

Let the intersection point be C. Following the same procedure, point C
3rd to 19th isochronous lines t leading to ~S.

~normal l to tts! .about.j'19 (thereby, one continuous filling flow diagram as shown in FIG. 2 can be drawn).

Therefore, by extracting each divided element through which the filling flow line drawn in this manner passes, a series of element areas as shown by hunting in FIG. 1 can be displayed.

In this way, according to Akira Hongo, by using an isochronous diagram as a conventional filling pattern into a mold, the flow situation of resin when resin is filled can be easily expressed as a fixed reference line. and display a series of areas corresponding to the reference line corresponding to the divided elements of the shape model of the molded product to easily determine whether or not the progress of the resin filling the mold is appropriate. Can be done.

The analysis processing for performing the above-mentioned display can be easily performed by arithmetic processing using a computer, and the results of these analysis processing can be displayed on a liquid crystal, CRT, plasma,
It can be easily displayed graphically using a display device such as an EL.

In the above-described embodiment, an arbitrary point A was selected from the gate position g to the first isochronous line t, but in this case, various filling flow lines could be displayed by changing the selected point in various ways. Of course, it is also possible to make a comprehensive judgment on suitability by displaying various filling flow lines at the same time.

〔Effect of the invention〕

As is clear from the embodiments described above, according to the present invention,
When performing flow analysis when filling molten resin into a mold made of a required shape model, it is possible to obtain a reference filling flow diagram based on the isochronous diagram showing the filling pattern. The suitability of the filling pattern passing through the points can be easily determined. In addition, by displaying a series of divided element areas that match the filling flow line in combination with the element-divided geometric model, it is possible to determine whether the resin progress status corresponding to the geometric model is appropriate.

Therefore, according to the present invention, when performing a resin flow analysis on a shape model of a molded product, it is possible to easily determine whether or not the injection speed of the molten resin is suitable for obtaining a high-quality molded product using a simple graphical display. Based on this determination result, various appropriate molding conditions can be selected, particularly the injection speed can be appropriately set, which is highly effective in contributing to the creation of a mold molding program for molten resin.

In addition, in the above-mentioned example, the method of displaying the flow analysis results in mold molding of molten resin was explained.
The present invention is not limited to this embodiment, and may be applied to molding of molten materials other than resin, for example, to die casting machines, and various design changes may be made without departing from the spirit of the present invention. Of course, it is possible to do this.

[Brief explanation of the drawing]

FIG. 1 is a graph ink display diagram showing a filling flow line and a series of regions of divided elements corresponding thereto, showing an example of a method for displaying flow analysis results in mold molding of molten material according to the present invention; Figure 2 is a graph ink display showing the analysis method of the filling flow line shown in Figure 1, Figure 3 is a graphic display of the shape model of the molded product divided into two-dimensional minute elements, and Figure 4 is 4 is an isochron diagram of a filling pattern in the shape model shown in FIG. 3. FIG. t1~tts,,, isochronous line! , ~”1! ,, Normal line A08. Any one point B-3 on the first isochronous line t1,,
, the intersection g06 of each normal line and each isochronous line. Gate position patent applicant Toshiba Machine Co., Ltd.

Claims (2)

[Claims] (1) In a system that divides a molded product shape model into minute elements and analyzes the flow of molten material in a mold using numerical analysis methods including the finite element method, boundary element method, finite difference method, FAN method, etc. , Divide the total time required in the process of filling the molten material into the mold into an arbitrary number, represent the filling progress at each time as an isochron diagram, and find points corresponding to any element on any isochron line. Select and set , draw a normal to the isochronous line from this set point, then set the intersection of the normal and the adjacent isochronous line, and draw the normal to the isochronous line from this set point. A method for displaying flow analysis results in mold forming of molten material, characterized in that a filling flow diagram is created and displayed using set points for each of the isochronous lines and a normal line connecting these. (2) In the method for displaying flow analysis results in mold forming of molten material as set forth in claim 1, an element that overlaps a part of the filling flow line is added to the divided micro elements of the molded product shape model. A method of displaying flow analysis results in mold forming of molten material by specifying and displaying these areas.