JPH01255006A - Method for forming offset shape - Google Patents

Abstract

PURPOSE:To reduce the number of intersections, to simplify a shape separation processing, and to shorten the generating time of offset shape by handling a closed loop by separating from original shape. CONSTITUTION:Final shape inputted from a keyboard 204 is processed at a CPU 200 by a control program stored in a ROM 201a, and is stored in a RAM 202 as a final shape block string. The intersection of each block is found, and the closed loop formed at the intersection is separated. Furthermore, the intersection in the closed loop itself is found, and when the intersection exists, the closed loop formed by the intersection is separated. And it is judged whether a separated intersection is valid or invalid, and the offset shape is generated by a valid closed loop or another block not comprising the closed loop.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an offset shape creation method for creating a corrected shape that is offset by a fixed amount from a given final shape.

[Prior Art] FIG. 28 is a block diagram showing a conventional offset shape creation device. In the figure, (200) is a central processing unit (CP
U), (201) is a ROM that stores the control program, and (202) is a RAM that stores the final shape and offset shape, and also serves as a work area for use in calculating the offset shape.

(203) is a CRT for displaying information for inputting final shape data from a keyboard (204) and offset shape.

FIG. 29 and FIG. 30 are explanatory diagrams of contour machining of a machining center and an explanatory diagram of the center shape of the tool. In the figure, (205) is the material, (206) is the tool, and (207)
) is the final shape, (208) is the tool center, (209) is the tool center shape, and (210) is the offset amount.

Only the final shape (207) is given in the contour machining of the machining center, and therefore the tool (200
), that is, the tool center shape (
209) must be found. At this time, the final shape (20
7), the shape is offset by the tool radius or the tool center shape (209), and this shape is called an offset shape.

FIGS. 31 and 32 are flowcharts showing arithmetic processing for obtaining the offset shape.

′! The case of creating an offset shape with respect to the final shape in FIG. j434 will be described with reference to the flowcharts in FIGS. 31 and 32.

Here, for example, the final shape shown in FIG. 34 is PO-Pl,
-R2-Pa -R4-R5-Pa -R7-
It is assumed that the final shape data block sequence is R8-R9. If you input this data from the keyboard (204) while looking at the CRT (203), the data will be sent to the RA.
M (202). The data of each block in this final shape data block sequence consists of a flag part and a shape part (see Figures 3 and 4 (A) and (B)), and in particular, the shape part contains the coordinates of the end point of the block. , and equations that specify its shape. The final offset shape data block row for that final shape data block row is ○〇−Of −01”CR1−CR2−08′−0
The method for obtaining this final offset shape data block sequence will be described below.

First, according to the control program in the ROM (201), the correction point 00 of the starting point shifted by the offset amount in the vertical direction of the final shape is calculated for the final shape data block (hereinafter referred to as block) PO in FIG. 34 (9
0). Next, the correction shape Of − for block P1 is
01' is created (91).

Connect that correction shape with the correction point 00 corresponding to the previous block, and then connect the offset block row 00-01.7Ql°
(92). In this way, blocks P2, Pa・
・The correction shape for R9 is not calculated until the final block is reached (93). All these shapes are stored in RAM (202).

The shape obtained as a result of the above processing is the offset block row 00-01-01"02-02°-03-03'-04
-04"05-05'-08-08゛-07-07°-
This is a shape connected by 08-08°-09, and this is called a simple offset shape data block sequence.

Note that these arithmetic processes (90) to (93) are the same arithmetic processes as in the embodiment described later, and details will be explained in the embodiment.

Next, the process of separating closed loops for this shape is performed by R
This is done according to the control program in OM (201) (215).

FIG. 32 is a detailed flowchart of this closed loop separation process. First, find all the intersection points of the shape formed by the above simple offset shape data block sequence (211
i). To find this intersection, for example, the offset shape block 01 is defined as shape 1, the next offset shape block o1° is defined as shape 2, and the presence or absence of an intersection between shape 1 and shape 2 is determined.

Since there is no intersection here, shape 2 is advanced to the next offset shape block 02, and the presence or absence of an intersection is similarly determined. In this way, shape 2 is advanced sequentially until the final block 0
Repeat the above process up to 9.

In this way, if shape 2 does not intersect with any other offset shape block even if it is advanced to the last offset shape block, shape 1 (01) does not have any intersection with another offset shape block.

Therefore, the offset shape block of shape 1 is advanced by one to 01', and shape 2 is moved to the next offset shape block 02.
, repeat the same process as above.

This process is repeated until shape 1 is at block 08', which is one block before the final block, and shape 2 is at block 09, which is the last block.

Through such arithmetic processing, the intersection points are the intersection CR1 between offset blocks 02 and 06°, the intersection CR2 between offset shape blocks 06" and 08, the intersection CR3 between 02 and 08,
Intersection CR4 between 03 and 06°, CR5 intersection between 03 and 08,
All the intersection points CR1 to CR12 are obtained in this way.

Next, an intersection table is created for the intersection points obtained here. This intersection table shows the coordinate values of the intersection points and the intersection of which block and which block of the offset shape blocks the intersection points are.

For example, the coordinate value of CRI, the coordinate value of CR2...02
A table is created such as 0B'oe' og.

Then, all closed loops are separated (217). In this process, a closed shape table is created based on the simple offset shape data block sequence and the above-mentioned intersection table.

As a result, the shape is 00-01-01°-CRI-CR2
-08'-09 and closed loop CRI -CR2-CR3
, CRI-CR4-CR5, CR4-CR7-02
', CR42CR6-CRIO-CR7.

CRIO-CRII-07°, CR5-CR8-C
R9-CRLI-CRIO, CR9-02-CRII,
CR6-CR8-CR9, CR3-CR6-0,C
R2-06°-07-CR8-CR8-CR3, CR8
-On -04-CR12-05°-0ff -C
R7-CRIO-07°-CRII-02-CR9,C
A closed shape table separated into 12 closed loops of R12-04'-05 is created. Then, for each closed loop, a flag indicating the direction of progress of each block is set.

After that, in each closed loop, closed loops whose traveling direction is not constant as shown in FIG. 33 are deleted (21g). Furthermore, among the remaining ones, even though the shape connection is concave, an invalid tag is attached to the corrected shapes that have no intersection, and the closed loop with this invalid tag is deleted (219
). The reason for deleting closed loops in this way is that if there are closed loops whose progression method is not constant as described above or closed loops with irregular tags, they will interfere with other correction shapes and cause a predetermined offset amount to the final shape. This is to prevent the occurrence of a situation where the material cannot be maintained and is cut too much.

After the above processing, the shape specified by the remaining offset shape block is output as an offset shape (22
0).

In the example in Figure 34, the remaining offset shape blocks are 0
0-01-Of'-CRI-CR2-08"-09, and this offset shape data block sequence is output as an offset shape.

[Problem to be solved by the invention] The conventional offset creation method was performed as described above, so in order to separate closed loops, it is necessary to find all the intersections and create all the closed loops made up of the intersections. In addition, there are problems in that the processing is complicated and requires a lot of calculation time, such as the need to record the direction of movement of each block.

This invention was made to solve the above-mentioned problems, and provides an offset shape creation method that makes it possible to shorten the offset shape creation time by simplifying and speeding up the process of separating closed loops. The purpose is to obtain.

[Means for Solving the Problems] An offset shape creation method according to the present invention is a method for creating an offset shape for a final shape specified in a final shape data block sequence including straight line or circular arc blocks. The method includes a step of creating a simple offset shape data block sequence in which the block is shifted by a predetermined offset amount in order from the first block.

Furthermore, for each block in the simple offset shape data block sequence, intersection points with other blocks are sequentially determined,
A closed loop separation processing step in which a closed loop formed by the intersection points is extracted and separated, and the intersection points of the closed loops are similarly sequentially determined, and a closed loop formed by the intersection points is extracted and separated. ,
Next, the method includes a step of determining whether the separated closed loop is valid or invalid, and a step of deleting the invalid closed loop and creating a final offset data block sequence of valid closed loops and blocks that do not constitute a closed loop.

[Operations] In this invention, the intersection points of each block of the simple offset shape data block sequence are determined, and the closed loop formed by the intersection points is separated.

The closed loop is then treated separately from the original shape. Then, the separated closed loop itself is further searched for an intersection point, and if there is an intersection point, the closed loop formed by the intersection point is separated. Then, it is determined whether the separated closed loop is valid or invalid, and an offset shape is created using the valid closed loop and other blocks that do not constitute the closed loop.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. Second
The figure is a configuration diagram of an offset shape creation device for implementing the method of this embodiment, and this is a ROM (201a)
The control program stored in the device is different from the device shown in FIG. 30, but the heart configuration itself is the same, so a description thereof will be omitted.

Next, the operation will be explained. Block PO- in Figure 20
Pl-P2-P3-P4-P5-P6-P7-P8-P
The case of creating an offset shape when 9 is the final shape will be described below.

The final shape indicated by the X and Y coordinate values of the points po, pi, ..., P9 in Fig. 20 input from the keyboard (204) in Fig. 2 is determined by the control program stored in the ROM (201a). It is processed by the CPU (200) and stored in the RAM (202) as the final shape data block sequence A shown in FIG.

The structure of each block at this time is as shown in FIG. 3, for example, and each block consists of a flag part (11) and a shape part (12). The structure of the flag part (11) is, for example, as shown in FIG. 4(A), where each bit has a straight line or a CW arc indicates a CCW arc, and the X axis is from the end point of the previous block.

It consists of a bit indicating an increase/decrease in the Y-axis direction, a bit indicating an invalid tag (described later), a bit indicating that the block is the final block of the final shape data block sequence, etc.

Further, the shape section (12), as shown in FIG. 4(B), consists of data on the x and y end point coordinate values of each block, and data representing the shape of the end point of that block and the end point of the previous block. For example, in the case of a shape or an arc, the data representing the shape is the x, y coordinates (Cx) of the center of the circle.

Cy) and radius r1 If the shape is a straight line, for example, a straight line equation such as Hessian equation (COSθ x + sinθ
The coefficients cos θ, sin θ, d of x=d) are input. Note that at the starting point, that is, the first block, the end point coordinates 1 mx, y of the shape portion represent the starting point coordinate values of the shape, and other data are meaningless.

Note that the format of this block is the same for each block such as a simple offset shape data block sequence B, which will be described later.

FIG. 5 is a flowchart showing a process for obtaining an offset shape for the final shape data block sequence described above.

First, an offset shape 00 is created as a correction shape for the starting point block PO, and is stored as the first block of the simple offset shape data block "' column B as shown in FIG. 1 (90). This starting point block PO An offset shape block OO can be obtained by simply shifting its starting point in the vertical direction of the shape by the offset amount.

Next, an offset shape for the next block is created (91). Then, the created offset shape blocks are sequentially stored and connected to form a simple offset shape data block sequence B (92). This process is repeated until the final block P9 (93)
.

By the way, each offset shape block is created by the method shown in the explanatory diagrams of FIGS. 6 to 10. The offset shape for a straight line block is a shape in which the original shape (final shape) is shifted to the right or left with respect to the direction of travel, as shown in Figures 6 and 7, and the slope of the straight line is unchanged and the original shape It is created by increasing or decreasing only the distance to the offset amount.

The offset shape for the circular arc is such that the center of the circle is the same and only the radius is increased or decreased by the offset amount, as shown in FIGS. 8 and 9. Note that FIGS. 8 and 9 are examples of circular arcs within CW, or in the case of CCW circular arcs, the right side correction and left side correction are simply reversed, and are created in the same manner.

Also, when offset to the inside of the arc, offset 1
- If the amount is larger than the radius of the arc, connect it with the previous block with a straight line as an offset shape as shown in Figure 11,
The invalid tag in the flag section of the block is set to 1.

Furthermore, an offset shape for a certain block is defined as an offset shape for an end point up to the start point of the next offset shape. At this time, if the shape of a certain block and the next block are connected or convex, the first
The offset shape for P in FIG. 1 is two blocks 01 and 02.

In addition, when the connection is concave as shown in Fig. 12, if there is an intersection between the offset shape of the previous block end point and the block end point, and the offset shape of the relevant block end point and the next block end point, the intersection point or the offset shape It becomes a block.

Furthermore, as shown in FIG. 13, when there is no intersection between offset-shaped blocks, two blocks, the offset-shaped block at the end point of the block and the offset-shaped block at the start point of the next block, become offset-shaped blocks. However, at this time, for the offset shape block at the start point of the next block, the invalid tag in the flag section of that block is set to 1.

In this way, if a predetermined offset amount cannot be maintained with respect to the final shape, the illegal tag in the flag section is set to 1. Therefore, for example, this also applies to the case where the moving directions (rotation directions) of the blocks forming the closed loop are different (FIGS. 27 and 33).

Furthermore, when the shape is smooth as shown in FIG. 14, the offset shape for a certain block is generated as is. In addition, in FIGS. 11 to 14, P is the corresponding block, 0
Or 01 and 02 are offset shape blocks.

In addition, at this time, the determination of whether the connecting part of the blocks is convex or concave is made for the target block and the next block as shown in FIG.
Vectors of length perpendicular to the block shape Vl, V
2, obtain the cross product VIXV2, and determine whether the sign is positive or negative.

Therefore, since the connection of the next block P2 to block P1 is convex, an offset-shaped block 01.01° is obtained by the method shown in FIGS. 6 and 11.

For block P2, the connection with the next block P3 is concave, and since there is no intersection between the offset shapes, offset shape block 02.02 is connected to block P2 by the method shown in FIG.
° is obtained.

Since the block P3 is connected to the next block P4 in a convex manner, an offset-shaped block of 03.03° is obtained by the method shown in FIGS. 6 and 11.

For block P4, since the connection with the next block P is concave and there is no intersection between the offset shapes, offset shape block 04.04' is processed using the method shown in FIG.
is obtained. For block P5, an offset-shaped block 05.05' is obtained by the same method as for block P4. Since the block P6 is connected to the next block P7 in a convex manner, an offset-shaped block o6.06° is obtained by the method shown in FIG.

Furthermore, for block P7, the connection between the next block and P8 is concave, and there is no intersection between the offset shapes, so the first
Offset shape block 07 by the method shown in Figure 3
．． 07' is obtained. Since the block 08 is connected to the next block P9 in a convex manner, an offset-shaped block 08.08° is obtained by the method shown in FIG. An offset-shaped block o9 is obtained using the method shown in FIG. 6 for block P9.

The offset shape blocks created as described above are sequentially stored to form the simple offset shape block sequence B shown in FIG. 1 (92).

At this time, the X axis of the flag part of each offset shape block,
A Y-axis increase/decrease flag is also created. Further, if the X, Y increase/decrease flag of the original shape is different from the increase/decrease flag of the offset shape, the illegal tag in the flag section is set to 1.

For example, the X, Y increase/decrease flag of block P2 in FIG.
This is different from the X and Y direction increase/decrease flag of offset shape 02 for 2, so in such a case, set the invalid tag to 1
Set to . Therefore, in the example of FIG. 20, the incorrect t of offset shape blocks 02°, 04', 05°, and
ag is set to 1.

The above calculation operations are repeated until the final shape <93)
, determine whether the final shape is old or not by bit 15 or 1 in the flag section.
It will be determined later whether it is set to .

Next, closed loop separation processing is performed on this simple offset shape cheater block row B (94). This closed loop separation process is performed based on the following idea.

Here, when we examine a series of consecutive data blocks in order from the beginning, if a block has an intersection with another block, it is a closed loop, and that closed loop can be considered independently of the original shape. can. In other words, if the closed loops are independent, it will be a minute! The progress directions of the blocks in the closed loop do not become inconsistent, and there is no need to consider the progress between the blocks forming the closed loop.

For example, in FIG. 17, if (AA) is a data block sequence that may include a closed loop, and blocks P1 and P2 have an intersection, (AA) is the closed loop of (B B) and the intersection of (CC). It can be separated into closed loop. Further, once the shape is separated and divided into two, even if one of the separated shapes has an intersection with the other separated shape, there is no need to consider it. It is only necessary to consider whether further separation occurs within each separated shape.

If closed loops are separated using this approach, the number of intersections that must be found will be far fewer than in the past.

Figures 18 and 19 show the above closed loop separation = 1
9 - shows a flowchart of the process.

In FIG. 18, first, the shape of block 01 is adopted as intersection calculation shape 1 (100). This is a process of specifying a block to be used as a comparison standard. Next, the block next to the intersection point calculation shape 1, here the shape 01', is adopted as the intersection point calculation shape 2 (1. OI). Find the intersection of this rear intersection calculation shape (01°OlN (1,02
), its presence or absence is determined (103).

Here, the determination of the presence or absence of an intersection between the intersection point calculation shapes 1 and 2 is as follows:
The shape part of each block is determined from the algebraic formula (see Figure 4 (B)), and if there is no real number solution, or even if a real number solution is obtained, it is not on both blocks, the intersection point It is judged as ephemeral.

Here, since there is no intersection between the shape of the offset shape block 01 and the shape of the offset shape block 01°, the process jumps to step (110) in FIG. 19. In this process (110), it is determined whether the intersection point calculation shape 2 is the final shape or not, since 01゛ is not the final shape (110)
, the following offset shape block 02 is adopted as the intersection point calculation shape 2 (1.+-1,). Below, in the same process flow as above, the intersection calculation shape 2 is offset shape block 0
It becomes 9 (102,103.1.10°111). In this way, the shape of offset shape block 01 and other offset shape blocks Of', 02.02°...
...The intersections with the shapes 08' and 09 are sequentially found, and it can be seen that the shape of the offset shape block 01 does not intersect with any other offset shape block shape.

Since offset shape block 09 is the final shape (110
), proceeding to the next process, it is determined whether AC calculation shape 1 is one block before the final block in the simple offset shape data block sequence (112). Here, the offset shape block 01 corresponding to the AC calculation shape 1 is not the block immediately before the final block, so the process proceeds to the next step. In the next process, the block 01° next to 01 is adopted as the intersection calculation shape 1 (113), and the process is repeated (101
).

In this process (101), block 02, which is the next block of block 01' of the current intersection point calculation shape 1, is adopted as the intersection point calculation shape 2.

The same process as above is then performed until an intersection point is found.

In the end, the intersection point is found when calculated shape 1 is 02 degrees and calculated shape 2 is 03 degrees. In this case, the process proceeds to step (104), where the shape is separated into two parts according to the concept described above. The separated closed loop shapes are stored in the closed loop separation work area C shown in FIG.

At this time, the intersection of offset shape blocks 02 and 03° is C
If RO, blocks CR0, 02°02° are stored in the closed loop separation work area C.

Next, the same process as before is performed to see if this shape is further separated into closed loops (105), and when it is confirmed that it will not be separated any further (106), the separated closed loops are checked (106). 107). here,
The calculation process for determining whether there are further intersections in the separated closed loop is performed by setting intersection calculation shape 1 and intersection calculation shape 2 for the blocks in the closed loop in the same manner as above, and determining the presence or absence of an intersection between them. .

This closed loop check (107) determines whether or not there is a block with an invalid tag in the separated offset shape blocks, and if there is a block with even one invalid tag, that closed loop is deleted and the block is valid. Output only the closed loop (lQ'l).

This closed loop CR0, 02, 02° has an invalid tag in the offset shape block 02° as shown in Figure 21.
(marked with an X in the figure), and since it interferes with other offset shape blocks and is invalid, this closed loop is deleted and not output.

Next, it is determined whether the intersection point calculation shape 2 is the last block in the simple offset shape data block sequence (110).
, if the intersection point calculation shape 2 has reached the offset shape block 09, it is then determined whether the intersection point calculation shape 1 is the offset shape block 08°, which is one block before the final block of the simple offset shape data string. (112). Here, the intersection point calculation shape 1 is the offset shape block 02, and the offset shape block 02' is set as the intersection point calculation shape 1 (113).

Simple offset shape data string 00-0f-01'-CRO-03° left as above...
....Similar processing is performed for 09.

Then, the next intersection is found with block CRO and 06
The intersection point with ゛ is CRI. As shown in FIG. 22, the closed loop formed by this intersection CR1 is block CR1.
-03-04-04"-05-05'-06-CRI, and has an intersection CR2 in the closed loop and further includes a closed loop, so the closed loop CR2
-04'-05 and the closed loop CRO-03 in Figure 24.
...Separated into 06-CRI. However, each closed loop has block 04 with an incorrect tag (X mark).
°, CR2,05° are included, so both are deleted.

The next intersection is found in the offset shape block 0θ°
The intersection point CR3 between and 08 is CR3. As shown in FIG. 25, the closed loop formed by this intersection point consists of offset shaped blocks o6°-07-07°-CR3. However, since this closed loop also includes the offset shape block 07° to which the incorrect tag (X mark) has been attached, it is deleted.

When each closed loop shown in FIGS. 22 to 25 is deleted in the above manner, a correction shape of the offset block sequence 00-01-CRI-CR3-08°-09 shown in FIG. 26 is created, and this The final offset shape data block sequence D (FIG. 1) is output, and this is used, for example, as NC data.

If the center position of the tool is controlled based on this final offset shape data array, the final shape will not be cut too much.
Appropriate machining is performed. Of course, there will be some parts that cannot be cut below the diameter of the tool, but you can cut those parts again using a tool with a smaller diameter. In other words, this offset shape is a part that cannot be cut due to the size of the tool (for example, P3-
P6, etc.) can be removed as much as possible.

Intersections CRO to CR8 in Figure 20 and intersections CRO in Figure 34
As is clear from a comparison with .about.CR12, the number of intersection points is significantly reduced in this embodiment, indicating that the calculation processing time is reduced.

By the way, the arithmetic processing of the above embodiment is applicable not only to the shape shown in FIG. 20 but also to the case where the input shape itself is a closed loop as shown in FIG. 27, for example.

However, if the input shape is a closed loop, even if the rotation direction of the separated closed loop is different from the rotation direction of the input shape, it is necessary to add it to the conditions for deleting the closed loop, as in the case where the closed loop has an invalid tag. If the separated closed loop is normal (valid), the direction of movement will always be the same as the original final shape, but if it is not the same, if the shape of the offset shape block is traced as it is by the cutting edge of the tool, This is to deal with the situation where the final shape is cut out excessively.

Therefore, in the example of FIG. 27, the input shape is CCW, while the offset shape block 03-0 of the three closed loops is
3'-09 is CW, so it will be deleted.

Further, in the block diagram of the offset creation device shown in FIG. 2, the control program is stored in the ROM (20), a), but it may also be stored in the RAM (202).

Furthermore, in the upper air embodiment, the correction of the tool diameter in a machining center is described, but the present invention can be applied to all cases where an offset shape of a certain shape is determined, such as correction of the nose radius of a lathe. In addition, the structure of the data block is of course just an example, and all the information for each bit and node in the flag section may be assigned to another area, and the shape section may have a shape equation only when it is a circle, so that it is straight. In this case, it may be possible to have only the end point coordinate value.

[Effects of the Invention] As described above, according to the present invention, if simple offset shape data blocks have an intersection, a closed loop is formed by the intersection, and since the closed loop is treated separately from the original shape, the intersection The closed-loop separation process became faster because the number of ``shapes'' was reduced and the shape separation process was simplified. Therefore, the processing time for creating the offset shape is also shortened.

[Brief explanation of the drawing]

FIG. 1 shows the RA of the apparatus shown in FIG. 2 in an embodiment of the present invention.
FIG. 2 is a configuration diagram of an offset shape creation device that implements a method according to an embodiment of the present invention. FIG. 3 is an explanatory diagram of the structure of a shape data block. FIG. 4 (A) is an explanatory diagram of the structure of the flag part of the shape data block, FIG. 4(b) is an explanatory diagram of the structure of the shape part of the shape data block, FIG. 5 is a flowchart showing the method of the above embodiment, and FIG. 15 is an explanatory diagram showing a method of creating an offset shape, and FIG. 16 is an explanatory diagram of a method of determining connection of convex and concave portions. FIG. 17 is an explanatory diagram showing the concept of closed-loop separation processing,
Figures 18 and 19 are flowcharts showing details of the closed loop separation process in Figure 5, Figure 20 is an explanatory diagram showing the relative relationship between the final shape and the offset shape, and Figures 21 to 26 are closed loop shapes. An explanatory diagram of separation and validity judgment, @
FIG. 27 is an explanatory diagram of the offset shape of another embodiment. Fig. 28 is a configuration diagram of a conventional offset shape creation device, Fig. 29 is an explanatory diagram of contour processing of a machining center, and Fig. 3
Figure 0 is an explanatory diagram of the center shape of the tool, Figures 31 and 32.
The figure is a flowchart showing a conventional calculation process for determining an offset shape, and FIG. 34 is an explanatory diagram showing the relative relationship between the final shape and the offset shape. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Patent Attorney So Sasaki Yato 2 Chiku 1st Figure 2 Figure 3 @Kn<eJIIQFQ @E6 (F'f'li
LfrFIlPn-1 0n-1 -i-7 is the off of the bottle stand of 1 ton of yen f koji JI7i / ) shape ゛ No. 13
Figure 16 P5 P4 Figure 21 Figure 23 Figure 22 Figure 24 P5 P4 Figure 25 PI PO Figure 26 Figure 30 Figure 31 Figure 32 Figure 33 09 08' Figure 34 Procedural Amendment ( Method), Indication of the case Japanese Patent Application No. 1983-081355, Name of the invention, Offset shape creation method, Person making the amendment Relationship with the case Patent applicant address 2-2-3 Marunouchi, Chiyoda-ku, Tokyo Name (601) ) Mitsubishi Electric Co., Ltd. Representative: Moriya Shiki, Agent address: Amita Building, 5-8-6 Toranomon, Minato-ku, Tokyo Telephone: Tokyo (03) 459-0211 Name (6127) Patent attorney: Muneharu Sasaki, Date of amended order June 8, 1988 (Shipping date: June 28, 1988) 2. In column 7 of "Brief explanation of drawings" of the specification subject to the amendment, page 30, line 6 of the specification of the contents of the amendment, "G. ", insert "Figure 33 is an explanatory diagram of a closed loop in which the traveling direction is not constant." Nooooo＼ l:l l-

Claims (1)

[Claims] In a method for creating an offset shape for a final shape specified in a final shape data block sequence including straight line or circular arc blocks, a predetermined offset amount is provided for each block in the final shape data block sequence. A process of creating a shifted simple offset shape data block sequence, and sequentially finding intersections with other blocks for each block of the simple offset shape data block sequence, and extracting and separating closed loops formed by the intersections. At the same time, the intersections in the separated closed loops are also found sequentially,
A closed loop separation processing step that repeats the process of extracting and separating the closed loop formed by the intersection points, a step of determining whether the separated closed loop is valid or invalid, and a step of deleting the invalid closed loop and making it valid. An offset shape creation method comprising the steps of creating a final offset data block sequence using a closed loop and blocks that do not constitute a closed loop.