JP3156496B2 - CAD system that facilitates designation of on-surface lines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CAD (Computer Aided Design) system for creating an on-surface line on a curved surface based on a user's operation and performing graphic processing related to the instructed on-line based on a user's instruction. It is about.

[0002]

2. Description of the Related Art FIG. 4 exemplifies a configuration of a conventional CAD system as described above. This CAD system is a CPU (Central Processing Unit) for performing arithmetic processing on graphics and the like.
1, a memory 2 such as a ROM and a RAM for recording information about figures and the like, an auxiliary recording device 3 such as a floppy disk drive, a screen display device 4 such as a CRT for displaying information about figures and the like on a screen, and a user. A keyboard 5 and a mouse 6 for inputting information related to figures, commands, and the like based on the operation of the printer, an output device 7 such as a printer for outputting information on paper, and a paper tape input / output device 8 for inputting and outputting information via a paper tape. And a bus line 9 for transmitting information between these devices.

[0003] Using such a CAD system, for example, in order to design a die for trimming a plate-shaped workpiece drawn and formed, etc., several on-surface lines are formed on a curved surface, and these on-line lines are formed. When performing graphic processing relating to a predetermined line on the surface, such as creation of a draft surface or trimming of a curved surface, the user and the CAD system perform the processing shown in FIG. To perform those graphics processing.

That is, when creating a draft surface, the user first selects an on-plane line creation command in step 11 in FIG. 5, and then in step 12, a curve as shown in FIG. enter the C _t and the projection direction D and surfaces SF ₁ - SF ₅ or the like, thereby CAD system, the next step 13,
Curve C _t as shown in FIG. 6 (a) toward the projection direction D projected onto the curved surface SF ₁ - SF ₅ obtains a surface on line C ₁ -C ₈ by.

Next, here, the user selects a curved surface creation command using an on-surface line in step 14 in FIG. 5, and then in step 15, as shown in FIG. By inputting the angle θ, the sweep length L, and the like, and repeating the picking operation in the subsequent steps 16 and 17, the picking position is indicated by x marks (1) to (8) in FIG. the entered pick Menjo line C ₁ -C ₈ as shown, when you are finished, indicates that the input is terminated at step 17, thereby CAD system, the next step 18, FIG. 6 (c ), The input on-surface lines C _{1 to} C ₈ , the designated direction V, the inclination angle θ of the surface, and the sweep length L
Based on the above, a sweep surface SS having an inclination θ with respect to the designated direction V and a length L is created as a draft surface.

In the case of trimming a curved surface, the user first selects a trimming command for a curved surface in step 19 in FIG. 5 and then repeats the picking operation in steps 20 and 21 to obtain the trimming command shown in FIG. For example)
(B), the surface on line C ₁ and the other curves inputted by picking as trimming curves as shown the pick point at × marks marked with (b), when you are finished to input in step 21 is completed This causes the CAD system to create or update the closed trim curve t ₁ indicating the effective area of the curved surface SF _{1 in} the next step 22 as shown in FIG. by repeating the process, the trim curve t ₂ ~t ₅ closed respectively the effective area of the other of the curved surface SF ₂ - SF ₅ also create or update.

After the draft surface SS and the trim curves t _{1 to} t ₅ are created as described above, for example, an effective area is defined on the draft surface SS by the trim curves t _{1 to} t ₅ , respectively. by connecting the curved surface SF ₁ - SF ₅ has, can be created as shown in FIG. 6 (f), the shape of the trimming punch plate workpiece. In this specification, the term “curved surface” is used in a broad sense including “plane”, and the term “curve” is used in a broad sense including “straight line”.

[0008]

However, in such a conventional CAD system, when performing graphic processing such as creation of a draft surface and creation / update of a trim curve using an on-surface line as described above. In addition, there is a problem in that the user has to pick and instruct all the surface lines to be used one by one, and the user is required to perform a complicated operation.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a CAD system which advantageously solves the above-mentioned problems, and a CAD system according to the present invention, as shown in FIG. A surface line is created on a curved surface based on the operation described above, and a graphic process related to the specified surface line is performed based on a user's specification, and when the surface line is created, the created surface line is created. Investigate the adjacency between each other, the adjacency information holding means M1 for holding the information indicating the adjacency, and at the time of the graphic processing related to the on-surface line, based on the adjacency information between the on-surface lines, the instructed And a graphic processing means M2 for connecting the adjacent surface lines including the surface line to obtain an on-line line sequence and performing the graphic processing using the on-line line sequence. .

In the CAD system according to the present invention, the graphic processing means M2 may create a sweep plane from the line array on the plane.

In the CAD system according to the present invention, the sweep surface may be a draft surface.

Further, the graphic processing means M2 in the CAD system of the present invention may trim the curved surface using the on-plane line sequence as a trim curve.

[0013]

According to the CAD system of the present invention,
The adjacency information holding unit M1 examines the adjacency relationship between the created on-surface lines when holding the on-surface line, holds information indicating the adjacency relationship, and the graphic processing unit M2 relates to the on-surface line. At the time of the graphic processing to be performed, based on the adjacent information of the above-mentioned on-surface lines, the adjacent on-surface lines including the indicated on-surface lines are connected to each other to obtain an on-line line sequence, and the on-surface line sequence is used to obtain the on-line line sequence. Perform figure processing.

Therefore, according to the CAD system of the present invention, when performing graphic processing such as creation of a draft surface or creation / update of a trim curve using an on-surface line, the on-surface line to be used is an on-line line sequence. Is formed, it is sufficient for the user to indicate one of the above-mentioned line lines in the above-mentioned line-of-line line, without the user having to pick and indicate all of the above-mentioned line-by-line lines. Operation can be greatly simplified.

If the graphic processing means M2 creates a sweep plane from the line array on the plane, the operation of the user when creating the sweep plane as the graphic processing can be greatly simplified.

If the sweep surface is a draft surface,
By the graphic processing, for example, a user operation when creating a draft surface such as a mold part can be greatly simplified.

Further, if the graphic processing means M2 trims the curved surface using the on-plane line array as a trim curve, the user's operation when creating an upper surface of a mold part or the like by the graphic processing is greatly simplified. can do.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 2 shows a case where several on-surface lines are formed on a curved surface using a CAD system according to an embodiment of the present invention, for example, for designing a die for trimming a plate-shaped workpiece formed by drawing. FIG. 4 shows a processing procedure performed by the user and the CAD system of the embodiment when performing graphic processing such as creation of a draft surface or trimming of a curved surface, which is related to a predetermined surface line among the above-mentioned surface lines. FIG. 3 is a flow chart and FIG. 3 is an explanatory view showing the contents of the graphic processing. The CAD system of this embodiment also has the same configuration as the conventional ordinary CAD system shown in FIG. The graphic processing is executed by operating based on the program.

That is, in this case, the CAD system first sets the reference direction S for performing the trimming of the curved surface, which is set as the pressing direction by, for example, a die in step 30 in FIG.
Is set to, for example, the reference direction S (0, 0, 1), the effective side when dividing the curved surface by the trim curve is set to (monovalent side), and the operation mode is set to the automatic mode. Do. Here, the reference direction S (0, 0, 1) indicates that the vector indicating the reference direction S is oriented in the Z-axis direction,
The effective side (monovalent side) indicates that the area on the side of the curved surface that forms an obtuse angle with the sweep curved surface, of the area inside and outside the trim curve, is the effective area.
This indicates that the system automatically obtains the on-plane line sequence using the adjacent information described later.

After the initial setting, when creating a draft surface, the user first selects the on-plane line creation command in step 31 in FIG. 2, and then in step 32, in FIG.
As shown in (a), the curve _Ct , the projection direction D, and the curved surface SF ₁
Enter the - SF ₅ or the like, thereby the CAD system, the next step 33, the curve as shown in FIG. 3 (a) C
_t is projected onto the curved surfaces SF _{1 to} SF ₅ in the projection direction D to determine the on-surface lines C _{1 to} C _{8. In} the subsequent step 34, each of the determined on-surface lines C _{1 to} C ₈ is converted into those surfaces. Overline C ₁ -C
Check whether the continuous adjacent to the rest of which faces the upper line of the _eight registers the neighbor information indicating the adjacency, in such neighbor information table shown in Table 1. Therefore, step 34 corresponds to the adjacent information holding unit M1.

[0021]

[Table 1]

Then, the user selects a curved surface creation command using the on-surface line in step 35 in FIG.
At 36, the designated direction V, the inclination angle .theta. Of the surface, the sweep length L, and the like are input as shown in FIG. 3B. At the subsequent step 37, the previously set effective mode is automatically required. Switch accordingly. Note that this switching can be performed by picking and inputting a required one of the effective side modes displayed on the side of the screen as shown in FIG. When the area on the inverse side, which is the side forming an acute angle with the sweep curved surface, of the area inside and outside the trim curve is set as the effective area, the effective side may be switched to (divalent side), and the sweep is performed. The area on the inverse side, which forms an acute angle with the curved surface, can be used for forming the shape of a die, a die having a clearance angle, and the like. If trimming of a curved surface is not performed, the effective side may be switched to (none).

Further, the user can proceed to step 38 in FIG.
Then, as shown in FIG. 3B, by picking and inputting a required processing mode between the automatic mode and the single mode which are also displayed on the side of the screen, the initial setting is performed. an automatic mode in performs face on lines used optionally switching between a single-mode that the user enters one by one, followed by step 39, previously the CAD system is Menjo line C ₁ -C ₈ obtained Any one of them, for example, on-surface line C
₁ is picked and indicated by the crosses marked with (1) in FIG. 3 (b) so as to indicate the pick point, whereby the CAD system in the next step 40 first sets the processing mode to the automatic mode. It is determined whether the mode is the single mode or the single mode.

[0024] Then when the automatic mode is selected, the CAD system, in step 41 in FIG. 2, by referring to the neighbor information table, all continuous to the surface on line C _1, which is the input Men'uesen C ₂ -C ₈ sequentially determined enter, at subsequent step 42, it is determined whether the input line is closed, when the result input line of the determination is not closed and a single in step 40 If the mode is selected, it is determined in step 43 whether or not the user has instructed the end of the input. If not, the process returns to step 38 and waits for the user's input. If the user has instructed termination of the input, the process proceeds to step 44.
If the input line is closed in step 42, the process also proceeds to step 44.

In step 44, the CAD system performs on-line line sequences C ₁ to C _4, which are the input curve lines.
Based on C ₈ and the previously input designated direction V, surface inclination angle θ, sweep length L, etc., as shown in FIG. 3C, it has an inclination θ and a length L with respect to the designated direction V. Sweep surface SS
Is created as a draft surface.

Next, here, the CAD system is:
In step 45 in FIG. 2, it is checked how the valid mode is set. If the valid mode is (none), it is determined that the trimming of the curved surface is not performed as described above. Since the instruction has been given, the process returns to the state after the initial value setting in step 30 and waits for an input. If the valid mode is (monovalent side), the process proceeds to step 46. If the effective mode is (bivalent side), the process proceeds to step 49.

In the CAD system, in the step 46 when the valid mode is (single-valent side), FIG.
As shown in FIG. 4D showing the cross section BB of FIG. 4C, at the previous pick point (1), there is no cross section of the sweep surface SS, that is, the cross section line of the sweep surface SS when viewed from the reference direction S. (in the figure the left) side tangent TV does not face at the pick point (1) of, the right or left side upper line columns C ₁ -C _8, determine the effective side information. The right or left side of the curve is
Usually indicates the right or left when viewed toward the curve from the start point to the end point, since here the figure Menjo line columns C ₁ -C ₈ defines the start and end points when viewed counterclockwise, the In this case, the effective side is the line line C ₁ on the surface at the pick point (1).
Left -C _8, that is, inside the closed surface overline column C ₁ -C _8.

Further, the CAD system determines in a succeeding step 47 whether or not the valid side has been determined in the previous step 46, and if the valid side has been determined, proceeds to a step 48.
According to valid side information indicating whether the right side or the left side of the on-surface line sequence C _{1 to} C ₈ is valid, the curved surface SF _{1 as} shown in FIG.
Trimming curves t ₁ ~t ₅ closed indicating the effective region of - SF ₅
Create or update.

In the CAD system, when the effective mode is (bivalent side), in the above step 49, at the previous pick point (1), the previous sweep curved surface SS viewed from the reference direction S is obtained.
Pick point of the cross-section line of the sweep surface SS
On the side where the tangent vector TV is facing is the on-plane line sequence C _1-
The right or left side of C _8, determine the effective side information (in this case, the effective side surface overline column C ₁ in the pick point (1) -C ₈
On the right side, ie, outside of the closed line sequence C _{1 to} C ₈ ). In the following step 50, it is determined whether or not the valid side has been determined in the previous step 49. Also in the above step 48, the on-plane line rows C ₁ -C
_The closed trim curve t indicating the effective area of the curved surfaces SF _{1 to} SF _{5 according} to the effective side information indicating whether the right side of FIG. ₈ is valid or the left side is valid.
Create a ₁ ~t _5, or to update.

Note that, as shown in FIG.
If it is determined in step 47 or 50 that the effective side has not been determined because the tangent vector TV at the pick point (1) of the section line of S is oriented in the reference direction S, the process proceeds to step 51. The CAD system displays a vector V _R indicating the right side and a vector V _L indicating the left side at the pick point (1) as shown in FIG. 3 (g). Then, the vector on the effective side, for example, the vector V _R is picked and input as shown by the cross mark of (2) in FIG. 3B to indicate the pick point, whereby the CAD system performs the above-described steps. 48, the right side of the surface overline column C ₁ -C ₈ there is valid or left valid or effective side information, to create a trimming curves t ₁ ~t ₅ closed indicating the effective region of the curved surface SF ₁ - SF ₅ Or update. Therefore, steps 40 to 51 correspond to the figure processing means M2.

After the draft surface SS and the trim curves t _{1 to} t ₅ are created as described above, for example, an effective area is defined on the draft surface SS by the trim curves t _{1 to} t ₅ , respectively. By connecting the curved surfaces SF _{1 to} SF ₅ , a punch for trimming a plate-like work and other shapes as shown in FIGS. 3E and 3H can be created.

When the user wants to change the reference direction S, the user first selects a reference direction change command in step 53, and inputs a direction vector for a new reference direction S in the next step 54. Causes the CAD system to reset the reference direction S with the input direction vector in the following step 55.

Therefore, according to the CAD system of this embodiment, drawing processing such as creation of a draft surface and creation / update of a trim curve is performed using an on-surface line, and a punch or a punch for trimming a plate-like workpiece is obtained. When creating a shape such as a die, if the on-surface line to be used forms an on-line line array,
Even if the user does not have to pick and specify all of the on-surface lines to be used, it is sufficient to indicate one of the above-mentioned surface lines in the above-mentioned line array, so that the user's picking operation is greatly simplified. can do.

Although the present invention has been described above with reference to the illustrated examples, the present invention is not limited to the above-described examples. The creation may be omitted, and only the trimming of the curved surface having the on-plane line array as the trim curve may be performed. Although Menjo line columns C ₁ -C ₈ in the above example is closed may not closed surface overline column.

[0035]

Thus, according to the CAD system of the present invention which facilitates designation of on-plane lines, when performing graphic processing such as creation of a draft surface or creation / update of a trim curve using on-plane lines. If the on-surface lines to be used form an on-line line, one of the above-mentioned on-line lines can be used without the user having to pick and indicate all of the on-line lines to be used. It is enough to indicate the line on the surface,
The operation of the user can be greatly simplified.

If the graphic processing means M2 creates a sweep plane from the line array on the plane, the user's operation when creating the sweep plane as the graphic processing can be greatly simplified.

If the sweep surface is a draft surface,
By the graphic processing, for example, a user operation when creating a draft surface such as a mold part can be greatly simplified.

Further, if the graphic processing means M2 trims the curved surface using the on-plane line row as a trim curve, the user's operation when creating an upper surface of a mold part or the like by the graphic processing is greatly simplified. can do.

[Brief description of the drawings]

FIG. 1 is a CAD according to the present invention, which facilitates designation of an on-surface line.
FIG. 1 is a conceptual diagram illustrating a schematic configuration of a system.

FIG. 2 is a diagram illustrating a user who creates a plurality of surface lines on a curved surface using the CAD system according to an embodiment of the present invention and performs graphic processing related to a predetermined surface line among the lines; 4 is a flowchart illustrating a processing procedure performed by the CAD system according to the embodiment.

FIG. 3 is an explanatory diagram showing the contents of the graphic processing.

FIG. 4 is a configuration diagram showing a schematic configuration of a conventional CAD system.

FIG. 5 is a diagram showing a user and a conventional user when drawing several surface lines on a curved surface using the above-mentioned conventional CAD system and performing graphic processing related to a predetermined surface line among them; 6 is a flowchart illustrating a processing procedure performed by the CAD system.

FIG. 6 is an explanatory diagram showing the contents of the graphic processing.

[Explanation of symbols]

 M1 Neighboring information holding means M2 Figure processing means

Claims (4)

(57) [Claims] 1. A CAD system for creating an on-surface line on a curved surface based on a user operation and performing graphic processing related to the specified on-line according to a user's designation. An adjacency information holding unit (M1) for examining the adjacency relationship between the created on-plane lines and holding information indicating the adjacency relation; Graphic processing means (M2) for connecting adjacent surface lines including the specified surface line to obtain a line sequence on the basis of the specified surface line, and performing the graphic processing using the line sequence on the surface. A CAD system that facilitates designation of on-surface lines. 2. The CAD system according to claim 1, wherein said graphic processing means (M2) creates a sweep plane from said line array on said surface. 3. The CAD system according to claim 2, wherein the sweep surface is a draft surface. 4. The designation of an on-surface line according to claim 1, wherein the graphic processing means (M2) trims the curved surface using the on-line line sequence as a trim curve. CAD system made easy.