JPH0241503A - Punch shape dividing method - Google Patents

Abstract

PURPOSE:To obtain a product whose working accuracy is satisfactory by inputting an overlap quantity SV by which two shapes to be divided are overlapped to each other at the time of dividing a punch shape, executing the division so that the divided shapes are overlapped by SV each by placing two divided points between each other and executing blanking by two divided punch shapes. CONSTITUTION:Two points (divided points) A1, A2 for showing a divided position on a closed curve CLP which has been given, overlap length SV by which two shapes which have been divided are overlapped on the closed curve CLP, and a circular arc radius SR are inputted. Subsequently, by using these input data, overlap points Pi (i=1, 2...4) which have been executed clockwise and counterclockwise along on the closed curve CLP by length of half SV/2 of overlap length SV, respectively from the two divided points A1, A2 are derived. Next, at the time of dividing a shape which has been surrounded by the closed curve into two shapes, the division is executed so that the first and the second closed curves F1, F2 for specifying each divided shape both have curved parts P1, P2 and P3, P4 as curve elements. In such a way, the accuracy of a product is improved.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a punch shape dividing method for a progressive die CAD/CAM system, and particularly relates to a punch shape dividing method when punching a punch shape using at least two types of punch shapes. Regarding the division method.

<Prior art> As shown in Fig. 10, the progressive mold CAD/CAM system 1 includes a mold design system (CAD system) la that automatically designs a mold, and an NG system that creates NC data 2 for mold processing. It is equipped with a data creation system (CAM system) lb6.In addition, each system la and lb may be configured with separate devices, but in reality, the system program for mold design and the system program for creating NC data The system is constructed as appropriate by loading the files onto one computer.

In such a progressive CAD/CAM system 1, C
The AD system 1a interactively designs product placement, number of stages, pitch, etc. based on the input product shape (blank layout processing), and then interactively creates a punch shape or die shape (strip layout processing). The CAM system 1b automatically designs each plate constituting the progressive mold through mold concept processing, and the CAM system 1b receives shape data and processing information for each plate automatically designed by CADL a, and creates and outputs NC data.

By the way, when the punching area to be punched out by the punch press is large, a desired punching shape is obtained by performing a plurality of punching steps.

For example, when punching the punching shape CLP shown in the solid line in FIG. 7, the shape CL 3P is divided into two shapes F1 and F2.
At the same time, prepare two punch shapes that are the same as the first and second shapes F1 and F2, and use the first punch to punch the shape F1.
Then, a second punch is used to punch out a shape F2, and a punched shape CLP is punched out. but.

In such a punching process, the parting line A work HA2 portion is not accurately punched out, resulting in unstamped parts. Therefore, we decided to create two shapes with one part overlapping and two parts with the same shape so that there would be no unfinished areas.
A method for obtaining a desired punch shape by preparing two punch shapes has been developed (for example, Japanese Patent Application No. 59-09611
(See Specification No. 6).

According to this method, two points A1 and A2 (see FIG. 8) on a given punched shape CLP are specified as dividing points, and the arc radius SR is input, and the dividing point A1
, a circular arc ARCi with a radius SR having its center on the normal lines N1 and N2 of the punch shape CLP in A2
(i = 1, 2...), and then surround the punch shape CLP clockwise from the division point A□ with the arc ARC1, the straight AILL, the arc ARC3, and the curve cvi (see Figure 9 (a)). ) and the arc ARC2, the straight line L2, the arc ARC4, and the curve Cv in the counterclockwise direction from the 1st division point A1.
2 (see FIG. 9(b)).

<Problems to be Solved by the Invention> However, when punching is performed using the punch shapes Fl and F2 created by the conventional punch shape dividing method, the five division points A1. A
Since 2 is the end point on the two punch-shaped elements, there was a problem that the accuracy of the finished product after punching deteriorated at the dividing point.

In light of the above, an object of the present invention is to provide a punch-shaped dividing method that improves the precision of the finished product after punching.

Means for Solving the Problems> FIG. 1 is a schematic explanatory diagram of a punch-shaped dividing method according to the present invention.

CLP is a closed curve, CVi is a curve, A1 and A2 are dividing points 3
Pi (i=1.2..., 4) is the overlap point,
SV is the overlap length, SR is the radius, ARCi is the arc of radius SR, Ni is the normal, C1 is the center of the arc, LL, L
2 is a straight line.

<Effect> Two points (dividing points) A1 indicating the dividing position on the observed closed curve CLP. Input A2, the overlap length SV and one arc radius SR where the two shapes after division overlap on the closed curve CLP, and use these input data to calculate half of the overlap length SV from the two division points A and A2, respectively. Obtain the overlap points Pi (i=1.2...4) along the closed curve CLP by the length SV/2 in the clockwise and counterclockwise directions, and
When dividing the shape surrounded by P into two shapes, the division is done so that the first and second closed curves Fl and F2 that specify each divided shape both have curved portions p1p2 and pJp as curve elements.

〈Example〉 Figure 2 shows a CAD system for progressive die design to which the present invention can be applied.
1 is a block diagram of a CAM system.

11a is a processor, llb is a ROM, and llc is a RAM
, 12 is a graphic display device, 13 is a tablet device, 14a is a keyboard, I4b is an x-y plotter, 14c is a floppy drive, FLD stores created NC data, etc. A floppy 15 stores various data for mold design. It is a large-capacity storage device that stores files, automatically created NG information, etc.

In the tablet device 13, 13a is a tablet surface;
13b is a menu table, and 13c is a tablet cursor. A menu table 13b is pasted on the tablet surface 13a, and various items and data can be input by picking predetermined items written on the menu table 13b with the tablet cursor 13C. FIG. 3 is a partially detailed diagram of a function menu table related to the automatic design of such a progressive die, and is a blank layout section BTB.

A strip layout section STB etc. is provided,
In the shape design of the strip layout section STB, the "r division" function item PTB and the like are provided.

First, the operator converts the progressive mold CAD/CAM system into a mold design system (CAD system). Thereafter, the progressive die is automatically designed using a well-known method. That is,
The CAD system la (Fig. 11) interactively designs the product placement, number of stages, pitch, etc. based on the input product shape (blank layout processing), and then automatically creates the punch shape or punch shape (die shape). Design (strip layout processing).

FIG. 4 is a flow chart of a punch shape dividing method when automatically designing a punch shape. The punch shape dividing process according to the present invention will be explained below according to the flowchart shown in FIG. It is assumed that a punch shape CLP automatically designed by the strip layout process is drawn on the CRT of the graphic display device 12 (fifth
(see figure).

The operator selects the strip with the tablet cursor 13c.
After picking layout part STB, r division” function item PT
Pick B (step 101).

By picking the "split" function item PTB, processor l
Since la asks the CRT about the punch shape to be divided, the punch shape CLP is picked in response to the question (step 102).

Next, the processor lla queries the CRT for the data necessary to divide the punch shape CLP, so in response to the question M, first, the division point A1 on the punch shape CLP is
, A2, or point 1 to A1.
The coordinate values of A2 are input using the keyboard 14a (step 103), and then the arc radius SR and the overlap length SV at which the two shapes to be divided overlap on the punch shape CLP are input (steps 104 and 105).

Division point A1. A2. In response to the input of the arc radius SR and the overlap length SV, the processor lla asks whether the punch shape CLP can be divided (step 106), and if it is not to be divided, the punch shape division process ends.

On the other hand, in the case of one division, the processor lla calculates the overlap length SV from the two division points A1 and A2.
Identify the overlap points Pi (i=1, 2...4) (see Figure 1) along the punch shape CLP by half the length SV/2 in the clockwise and counterclockwise directions. , overlap curve part P on the punch shape
Identify 3P, 3P3P. If the element in which the first dividing point Ai and the overlap point Pi exist is an arc element, the half length SV/2 of the overlap length SV is the length along the arc (see Fig. 6(a)). , (b))
. Also, if the point shifted by half the length SV/2 of the overlap length SV along the element (straight line or circular arc) where the two-division point Ai and the overlap point Pi exist is not on the element, an error will occur. .

Next, overlap curve parts P1P and 3P3P.

Of the two curves of the punch shape CLP separated by the overlap curve part p1p, the curve CVI reaches the overlap curve part p3p counterclockwise from the overlap curve part p1p2, and the overlap curve part P3P goes clockwise from the overlap curve part p1p2. Specify the curve CV2.

Then, an arc A RCi (i = 1, 2, . . . 4) with a radius SR having a center Ci on the normal Ni of the punch shape CLP at each overlap point Pi is specified, and each point on one arc ARCi is defined as Qi. (i=1.
2...4), the clockwise arc portion of arc ARC1 from overlap point P1 and points 1 to Q
,, Q, the straight line L□ connecting the points Q3, the clockwise arc portion of the arc ARC3, the overlap curve portion P3P4, the curve CVI, the overlap curve portion p1p, and the first punch shape F1 is specified. . still,
End point Q0. Q is the point of contact when the straight line L□ touches the arcs ARC1 and ARC3 in the same way, and the end points Q,,Q, are the points of contact when the straight line L
2 is the contact point when it touches the arcs ARC2 and ARC4 similarly.

A straight line L2 connecting the counterclockwise arc portion of the arc ARC2 from the overlap point P2 and points Q2 and Q4.
, the counterclockwise arc portion of the arc ARC4 from the point Q4, the overlap curve portion P3P4, and the curve C
V2, the overlap curve portion p1p, and the second punch shape F2. Then, the shape surrounded by the given punch shape CLP is defined as the first and second punch shapes F.
Step 1 Divide into shapes surrounded by l and F2.
07), the punch shape division process ends.

The above completes the input of data necessary for creating NG data for punch-shaped CLP processing. After that.

After the mold concept design is completed, the operator stores the system program for creating NG data in the RAM 11.
c to create an NC data creation system (CAM system). Then, when the punch shape CLP is instructed, the processor lla creates NG data based on the divided punch shape data.

<Effects of the Invention> According to the present invention, when punch shape division is performed, the overlap amount SV at which two shapes to be divided overlap each other is input, and one divided shape is divided so that it overlaps each other by SV across two division points. By performing punching using two punch shapes, it is possible to obtain a product with good processing accuracy.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of the punch shape dividing method of the present invention. Figure 2 shows a CAD/mold design for progressive die design to which the present invention can be applied.
A block diagram of the CAM system, FIG. 3 is a partially detailed view of the menu table of the present invention, and FIG. 4 is a flowchart of punch shape division processing of the present invention. 5 and 6 are detailed explanatory diagrams of the present invention, and FIGS. 7 to 10 are explanatory diagrams of the conventional example. 11a... Processor. 11b -- ROM, 11c... RAM, 12... Graphic display device. 13...Tablet device. 13b...Menu table. 13c...Tablet cursor. L4a: Keyboard, CLP: Punch shape. Ai...Dividing point. SV: Overlap amount. SR...Radius, ARCi...Circular arc

Claims (2)

[Claims] (1) In a punch shape division method that divides a shape surrounded by a given closed curve so that some parts overlap, two points A_1 and A_2 indicating the division position on the given closed curve and 2 points after division are used. Specifying the overlap length SV and arc radius SR where the shapes overlap on the closed curve; From the two points A_1 and A_2, move clockwise and along the closed curve by half SV/2 of the overlap length SV, respectively. Specify the overlap points Pi (i=1, 2...4) in the counterclockwise direction, and identify the first and second overlap curve parts P_1, P_ on the closed curve.
2. identifying P_3 and P_4; the first and second overlapping curve portions P_1P_2;
, P_3P_4 in the counterclockwise direction from the first overlapping curve part P_1P_2 of the two closed curves separated by P_3P_4.
and a second curve CV2 clockwise from the first overlapping curve portion P_1P_2 to the second overlapping curve portion P_3P_4, each of the overlapping points Pi (i=1, 2...4
), specifying a circular arc ARCi (i=1, 2...4) of radius SR whose center is on the normal line of the closed curve passing through each of
...4), the clockwise arc portion of the arc ARC1 from the overlap point P_1 and the point Q_
1. Straight line connecting Q_3 and arc AR from point Q_3
A first closed curve is specified by the clockwise arc portion of C3, the second overlapping curve portion P_3P_4, the first curve CV1, and the first overlapping curve portion P_1P_2, and from the overlap point P_2 The counterclockwise arc portion of arc ARC2 and point Q_2
, a straight line connecting Q_4 and an arc ARC from point Q_4
identifying a second closed curve with the counterclockwise circular arc portion of No. 4, the second overlapping curve portion P_3P_4, the second curve CV2, and the first overlapping curve portion P_1P_2; A punch shape dividing method characterized in that a shape surrounded by a closed curve is divided into shapes each surrounded by a first closed curve and a second closed curve. (2) Based on the first and second closed curves, the first and second
A method for dividing a punch shape according to claim 1, wherein NC data for processing a punch shape is created.