JP4376190B2 - Structure shape design system - Google Patents

Description

The present invention relates to a structure shape of the design system.

Conventionally, in a structure shape of the design, the design method of the dimensions and shape function of the structure each part as a design variable, to explore the structure shape by performing a CAE (Computer Aided Engineering) structural analysis by changing the design variable It is taken.

In this conventional design method, the design variable is defined by the coordinates of the nodes included in the CAE data, and a method of obtaining the structure shape by moving the node coordinates is adopted.

Conventional structure design method, the structure shape is obtained by inputting the design area, a short time the shape of the topology (phase-form) structure with the change due to addition / deletion of such rib or boss Designing an optimal model that satisfies design specifications by inputting design specifications (for example, see Patent Document 1), structure design specifications, initial shape, application range of design parameters, and boundary conditions (for example, patents) Document 2) has been proposed.

Moreover, in the design of the cushioning material in the buffer packaging, a design method that relies on the intuition and experience of the designer referring to the cushioning performance data of the plate cushioning material is common, and CAD (Computer Aided Design) is used. However, there is no structural shape design system that can be used in combination with CAE structural analysis and can be designed including the possibility of molding and manufacturing costs.

JP 2001-297118 A Japanese Patent Laid-Open No. 3-224063

However, as in the prior art described above, the design of the structure shape that minimizes the volume or weight of the structure with the mechanical quantities such as strength as constraints is performed in various fields. There is no structural shape design system that handles the availability and manufacturing cost at the same time, and it is common and necessary to evaluate the formability and cost after determining the dynamic structural shape and determine whether it is appropriate. In some cases, the shape constraints were reviewed again and design calculations were performed again.

The present invention is made to solve the above problems, it is an object of the structure shape design system that can be designed in consideration of the structure shape to easily and accurately molded availability and manufacturing costs It is to be provided.

Typical construction of a structure shape design system according to the present invention includes an input means for inputting design data structure defines the structure shape based on the design data of the input structure by said input means CAD means, CAD / CAE conversion means for converting CAD data of a structure defined by the CAD means into CAE data, and CAE structure analysis for detecting a mechanical response amount for the structure shape converted to the CAE data Means for determining whether or not the structure shape defined by the CAD means can be manufactured, CAD data of the structure defined by the CAD means, and the dynamics detected by the CAE structure analyzing means A correlation between the response amount and the production availability information determined by the production availability determination means is detected, and the dynamics are detected based on the correlation. Amount response satisfies the design conditions of the structure and to the structure shape is detected so as to be manufactured by changing the CAD data of the structure, the CAD data of the structure was the change Based on the CAD data of the structure, the mechanical response amount, and the fabrication availability, the mechanical response amount determines the design condition of the structure based on the updated correlation. happy, and possess a that control means detect the production so that it becomes the structure shape, and display means for outputting and displaying the detected by previous SL control means the structure shape The structure is an article manufactured using a molding die, and the manufacturing possibility determination unit divides the article and the molding die into a plurality of planes perpendicular to the drawing direction when releasing the mold. The outer circumference of the cross-sectional shape of each cross-section projected from the drawing direction Characterized by determining the probability produced by not intersect Te.

Since the present invention is configured as described above, the CAD data of the structure inputted by the input means and the shape of the structure converted from CAD data to CAE data by the CAD / CAE conversion means are detected by the CAE structure analysis means. The correlation between the mechanical response quantity and the production availability information judged by the production availability judgment means is detected, and based on the correlation, the mechanical response quantity satisfies the design condition of the structure and can be produced. so as to change the CAD data of the structure until the structure shape is detected, and the CAD data of said structure on the basis of the CAD data of the changed structure, the mechanical response amount, and fabrication propriety update the correlation, mechanical response amount satisfies the design conditions of the structure on the basis of the updated correlation, and fabricated so that it becomes the control means detects a structure shape, The shown means, can be output displays the structure shape. This makes it possible to design a structure shape easily and accurately.

It is a block diagram which shows schematic structure of the structure shape design system which concerns on this invention. It is a flowchart which shows an example of the process sequence at the time of structure shape detection. And the cushioning material, the shape of the early design stage of the cushioning material for packaging the object to be buffered thereof illustrates in CAD data. It is a figure which shows a mode that the CAD data shown in FIG. 3 were converted into CAE data. And CAD data structure creation illustrates the mechanical response amount, and fabrication possibility, the correlation between the manufacturing cost. It is the figure which showed an example of the shape of the shock absorbing material which does not satisfy design conditions in the process of calculating | requiring a structure shape by CAD data. An example of a structure shape of loose衝材illustrates in CAD data. Other shapes of a gentle衝材initial design stage of a diagram showing the CAD data.

Specifically described an embodiment of applying the buffer material shape of design systems for use in cushioning packing as an example of a design system of a structure shape according to the present invention with reference to FIG.

  In FIG. 1, reference numeral 1 denotes an input for inputting design data required for designing a cushioning material 4 used for cushioning packaging, which is an article manufactured using a molding die as a structure to be designed. An input device as means for inputting design data via a communication line such as a keyboard, a mouse, or the Internet provided in a personal computer or the like.

2 is an arithmetic processing unit for calculating a structure in which shape of the cushioning material 4 performs predetermined arithmetic processing based on the design data input by the input device 1, 3 is calculated by the processing unit 2 a display device such as a CRT (cathode ray tube) or a printer serving as a display means for outputting and displaying the shape of the buffer material 4, the display device 3 the output load and display design result stored in the database file, etc. It also has a function to do.

Processor 2 controls the calculation process performed by the arithmetic processing unit, that system and control unit 2a Do the detection to that control means shape the cushioning material 4 is structure, is input by the input device 1 The CAD part 2b, which is a CAD means for defining the structure of the cushioning material 4 based on the design data of the cushioning material 4 serving as the structure, and the cushioning material 4 serving as the structure defined by the CAD part 2b A CAD / CAE conversion unit 2c serving as a CAD / CAE conversion means for converting CAD data into CAE data, and a CAE for detecting the mechanical response amount by CAE structural analysis of the structure of the buffer material 4 converted into the CAE data. The CAE structure analysis unit 2d serving as a structure analysis unit, the production availability determination unit 2e serving as a production availability determination unit that determines whether or not the structure of the buffer material 4 defined by the CAD unit 2b is manufactured, and the CAD unit 2b A cost calculation unit 2f such as a cost calculation means for detecting the production cost for the construction shape defined by a buffer material 4 is constituted.

In control section 2a, as will be described later with reference to FIG 5, a CAD data created on the basis of the design data of the cushioning material 4 made of a structure in a CAD unit 2b, detected by the CAE structure analysis unit 2d Mechanics The correlation between the response amount, the production availability information determined by the production availability determination unit 2e, and the production cost information detected by the cost calculation unit 2f is detected, and the production can be performed based on the correlation. basis weight response satisfies the design conditions of the buffer material 4, and change the CAD data of the buffer material 4 to a minimum manufacturing cost and so as a buffer material 4 shape is detected, to the modified CAD data Based on the CAD data, the mechanical response amount newly detected by the CAE structure analysis unit 2d, the production availability information judged again by the production availability judgment unit 2e, and newly detected by the cost calculation unit 2f Production cost Based on the information, the previous correlation is updated, and based on the updated correlation, the mechanical response amount satisfies the design condition of the cushioning material 4 and can be manufactured, and the minimum manufacturing cost is achieved. performing arithmetic processing you detect structure in which shape of the buffer material 4.

  In the present embodiment, when it is determined that the manufacture is possible by the manufacture possibility determination unit 2e, when the cushioning material 4 and the molding die are released, they are perpendicular to the drawing direction a shown in FIGS. Production is determined by projecting the outer periphery of the cross-sectional shape of each cross-section divided by a plurality of planes from the drawing direction a so as not to intersect.

  Further, as an example of the mechanical response amount detected by the CAE structure analysis unit 2d, in the present embodiment, the maximum deceleration, the maximum displacement, and the buffer material 4 that are generated in the buffered material 5 that is packaged by the buffer material 4 at the time of a drop impact. It is set to detect at least one of creep displacements that occur during long-term use.

Next, with reference to FIG. 2, illustrating an example of the process procedure of the structural shape design system according to the present invention to form shaped cushioning member 4 serving as a structure is detected. First, in step S1, design data of the cushioning material 4 serving as a structure to be designed is input as the input device 1 via a keyboard or a communication line such as the Internet.

For example, when designing the shape of the cushioning material 4 for cushioning packaging, as the design data, the shape of the buffer material 5, by weight, drop height, dropping direction, design tolerances (e.g., in the buffer material 5 Maximum deceleration that occurs, maximum displacement of the buffered object 5 for determining bottoming or falling off from the buffer material 4, creep displacement of the buffer material 4 for determining sag of the buffer material 4 during long-term use, Maximum stress generated in the buffer 5, maximum strain generated in the buffered object 5, maximum stress generated in the buffer material 4, maximum strain generated in the buffer material 4, allowable values of mechanical response such as the coefficient of restitution of the buffer material 4, etc. ), Mechanical property values (for example, stress / strain curve, Poisson's ratio, density, etc.) of materials used for the object to be buffered (article to be packaged) 5, the outer box and the buffer material 4. Further, the dimensions of the outer box such as a cardboard box, the position of the buffered object 5 to be stored in the outer box, and the like are input as design conditions as necessary.

  The mechanical properties of the materials used for the buffered object 5, the outer box, and the cushioning material 4 are prepared as a storage device or a database file storing such various data. Accordingly, the mechanical property value may be retrieved and used.

  When these design data are input to the arithmetic processing unit 2, the process proceeds to step S2, and the CAD unit 2b is used to create the CAD data M1 as shown in FIG. To do. At this time, shape data (for example, dimensions, angles, presence / absence of ribs and holes) serving as design variables are defined.

  In addition to the method of newly creating the initial design shape, the CAD data M of the previously designed case may be selected from a database or the like and used. At this time, a plurality of design initial shapes of different cushioning materials 4 as shown in FIG. 3 and FIG. 8 stored in the database are further selected, and a plurality of design initial shapes of the cushioning materials 4 and respective design initial shapes are selected. The shape data included may be defined as a design variable.

  In step S2, when the cushioning material 4 and the buffered object 5 are combined, the CAD / CAE converting unit 2c serving as the CAD / CAE converting unit is provided for the case where the buffered object 5 has a protrusion 5a or a curved surface part. The interference between the buffer material 4 (for example, the volume set A) and the buffered object 5 (for example, the volume set B) is examined. A subtraction process {A- (A∩B)} is performed on the interference portion (A∩B) with the buffer 5. The recess 4a of the cushioning material 4 is formed by subtracting the protrusion 5a of the buffered material 5 that becomes an interference portion from the cushioning material 4 side.

  At this time, 1 mm is provided at the boundary between the buffer material 4 and the buffered object 5 so that the calculation of contact between the buffer material 4 and the buffered object 5 in the CAE structure analyzing unit 2d serving as the CAE structure analyzing means can be performed. Provide a gap of a certain degree.

  Subsequently, the process proceeds to step S3, step S6, and step S7, and the following processing is performed in steps S3, S6, and S7 for the design data input in step S1 and the CAD data M defined in step S2.

First, in step S3, the CAD / CAE converter 2c converts the CAD data M defined in step S2 into CAE data N used for CAE structure analysis including the design data input in step S1. Thus, for example, the CAE data _{N 1} shown in FIG. 4 is obtained.

  For example, a general-purpose automatic element division program such as KUBRIX (trade name) manufactured by Simulation Works, Inc. is applied to the program for converting the CAD data M provided in the CAD / CAE conversion unit 2c into the CAE data N.

  Next, the process proceeds to step S4, and the drop impact analysis is performed on the CAE data N created in step S3 in the CAE structure analysis unit 2d. For this drop impact analysis, for example, ABAQUS (trade name) from Hibbitt, Karlsson & Sorensen, Inc., RADIOSS (trade name) from MECALOG SARL, LS-DYNA (trade name) from Livermore Software Technology Corporation, Engineering Systems International General-purpose CAE programs such as PAM-CRASH (trade name) manufactured by SA are applied.

  Next, the process proceeds to step S5, and a mechanical response amount for comparing the magnitude with a design allowable value such as the maximum deceleration generated in the buffered object 5 is calculated from the result of the drop impact analysis executed in step S4. For calculating the mechanical response amount, a post-processor provided in the general-purpose CAE program may be applied, or a program for outputting the analysis result as text data and editing the data may be used.

  On the other hand, in step S6, whether or not the manufacturability determination unit 2e appropriately applies a draft for releasing when the CAD data M defined in step S2 is manufactured using a molding die. Whether or not production is possible is judged by judging whether or not.

  The determination of whether or not molding is possible is that each of the cross-sections of the cushioning material 4 divided by a plurality of planes perpendicular to the drawing direction a gradually decreases in cross-section with respect to the drawing direction a and the outer periphery or inner periphery of the cross-section is extracted. Use a program to check that it does not intersect with the outer or inner circumference of another cross section when viewed from the direction a, or some CAD software (for example, Solid Works made by Solid Works Corporation) You may apply the draft check function.

  In step S7, the cost calculation unit 2f calculates the production cost for the CAD data M defined in step S2. For example, when a bead foam molded product is used as the buffer material 4, a value obtained by multiplying the volume of CAD data M corresponding to the material usage amount by the material unit price as the material cost, and a running cost of the molding machine, etc. are applied as the processing cost. The production cost is calculated.

  In addition, when an extruded foam product is used as the cushioning material 4, the raw material unit price divided by the number of raw fabrics taking into account plate cutting as the material cost, the cutting cost, the heat pasting cost, the die cutting Fees are applied and the production cost is calculated.

Then, the process proceeds to step S8, the mechanical response amount calculated in step S5, step S6 and step S7, the fabrication compliance information using the manufacturing cost information, mechanical and design variables CAD data M ₁ shown in FIG. 3 Correlation between the response amount, production availability and production cost is derived, for example, as shown in the graph of FIG. 5, and the design allowance of the shock absorbing material 4 that can be produced based on this correlation and the mechanical response amount is the design object. satisfies the value, and the manufacturing cost can determine the shape of the cushioning material 4 is minimized.

In the process of obtaining the shape of a design target of the cushioning material 4, for example, it does not satisfy the design conditions as CAD data M ₂ shown in FIGS. 5 and 6 (manufactured impossible, mechanical response amount exceeds the design tolerances ), Or if there is a buffer material shape that can be manufactured at a lower cost, the process proceeds from step S8 to step S2 until the final shape of the buffer material 4 is obtained. As shown in FIG. M is changed to update the correlation between the mechanical response amount, production availability and production cost, and the final shape of the cushioning material 4 is obtained.

FIG. 5 starts from the CAD data M1 shown in FIG. 3, and sequentially changes to CAD data M ₂ , M ₃ ,..., M _8, and for the ninth time, for example, the shape of the cushioning material 4 as shown in FIG. A state in which the CAD data Mopt in the form of a circle is obtained is shown. To shape the determined Ru control section 2a of the cushioning material 4 to be designed, for example, a general-purpose design program is applied such Engineous Software Inc. manufactured iSight (trade name).

  FIG. 8 is a diagram showing another shape of the cushioning material in the initial design stage as CAD data. In FIG. 8, 4 b is a hole drilled in the four corners of the buffer material 4, and 4 c is a slit extending from the hole 4 b to the opening of the buffer material 4. As described above, a plurality of design initial shapes of different cushioning materials 4 as shown in FIG. 3 and FIG. 8 described above stored in the database are selected, and the design initial shapes of the plurality of selected cushioning materials 4 and the initial design of each are selected. The shape data included in the shape may be defined as a design variable.

In the present embodiment, since CAD data M is used as a design variable, it is easy to create a drawing or NC data for machining with respect to the obtained structure shape.

  Further, since the element division is performed on the CAD data M every time the shape is changed, a distorted element is hardly generated, the analysis accuracy in the CAE structural analysis is unlikely to deteriorate, and a complicated shape such as an increase in ribs and holes is provided. Can easily handle changes.

Furthermore, since not only the mechanical response amount but also the production availability and production cost are added to the design conditions, it is possible to obtain a structure shape with higher productivity including workability and economy.

  In addition, although the said embodiment demonstrated the case where the buffer material 4 was applied as a structure, this invention is not limited to this, It can apply also to other various structures. In this case, the general-purpose CAE program used for the CAE structure analysis unit 2d may be changed in accordance with the structure to be designed, and the mechanical response amount to be evaluated, the production cost calculation method, and the like may be changed.

As an application example of the present invention, the present invention can be applied to a structure shape design system .

1 ... Input device
2 ... Arithmetic processing device
2a: Control unit
2b ... CAD part
2c: CAD / CAE converter
2d ... CAE structure analysis part
2e ... Production availability judgment part
2f ... Cost calculation unit
3. Display device
4 ... cushioning material
4a ... recess
4b ... hole
4c ... Slit
5 ... Buffered object
5a ... Projection
M, M ₁ ~ M ₈ , Mopt ... CAD data
N, N ₁ ... CAE data

Claims (3)

An input means for inputting the design data of the structure;
CAD means for defining the structure shape based on the design data of the structure input by the input means;
CAD / CAE conversion means for converting CAD data of a structure defined by the CAD means into CAE data;
CAE structure analysis means for detecting a mechanical response amount for the structure shape converted into the CAE data;
Production feasibility judgment means for judging production feasibility for the structure shape defined by the CAD means;
A cost calculating means for detecting a manufacturing cost for the structure shape defined by the CAD means;
The CAD data of the structure defined by the CAD means, the mechanical response amount detected by the CAE structure analyzing means, the production availability information judged by the production availability judgment means, and the cost calculation means The structure is detected so that the mechanical response amount satisfies the design condition of the structure, can be manufactured, and can be manufactured at the minimum manufacturing cost based on the correlation . change the CAD data of the structure until the shape is detected, and the CAD data of said structure on the basis of the CAD data of the structure was the change, and the mechanical response amount, the production possibility and the production The correlation with the cost is updated, and based on the updated correlation, the mechanical response amount satisfies the design condition of the structure and can be manufactured, and the minimum manufacturing cost And that control means detect the structure shape such that,
Display means for outputting and displaying the detected said structure shape by previous SL control means,
I have a,
The structure is an article manufactured using a molding die, and the manufacturing availability determination means is divided into a plurality of planes perpendicular to the drawing direction when releasing the article and the molding die. The structure shape design system is characterized in that it can be manufactured by projecting the outer periphery of the cross-sectional shape of each cross-section from the drawing direction so as not to intersect . The structure is a cushioning material used for cushioning packaging, and the CAE structural analysis means calculates at least one of maximum deceleration, maximum displacement, and creep displacement that occurs when the cushioning material is used for a long time. 2. The structure shape design system according to claim 1 , wherein the system is detected as the mechanical response amount. The structure is a cushioning material used for cushioning packaging, and the CAD / CAE conversion means investigates interference between the cushioning material and the buffered object, and when they interfere with each other, the cushioning material side 2. The structure shape design system according to claim 1 , wherein an interference portion with the buffered object is subtracted.

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