JP2000033533A - Tool locus formation device and tool locus formation method and memory medium readable by computer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tool locus formation device and a tool locus formation method and a memory medium readable by a computer capable of preventing the occurrence of an unnecessary part left uncut and forming a tool locus efficiently. SOLUTION: When a shape including an edge line EL expressing a completed shape of a mold and a predetermined machining finish allowance D is cut from a raw material, a base guide line (hereinafter referred to as BGL) which is a tool locus in X-Y direction and a guide line (hereinafter referred to as GL2) are obtained by repeating off-set. At this time, if there is a folding point smaller than a predetermined angle on GL2, the vicinity of the folding point on GL2 is trimmed so that regions to be machined are overlapped because it is expected that a part left uncut occurs because the regions to be machined are not overlapped and excessive load is applied to a tool when knocking machining is done at a predetermined pitch by the tool in accordance with these tool loci.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool trajectory creating device, a tool trajectory creating method, and a computer-readable storage medium. And a computer-readable storage medium.

[0002]

2. Description of the Related Art In recent years, so-called CAD (computer-aided design) and CAE (computer-aided engineering) have been proposed.
With the advancement of technology and the intelligentization of machining equipment, at the manufacturing site, a two-dimensional or three-dimensional shape of the article to be manufactured is generated in advance on a computer, and based on the generated shape data, a tool such as a cutting tool is created. Techniques for generating tool trajectory data are used.

As an application example of such a tool trajectory data generation technique, there is an application to a so-called tool trajectory during thrust machining. This piercing is performed, for example, by changing the material shape shown in FIG.
By rotating the cutting tool and repeatedly moving at predetermined tool feed pitches (hereinafter, predetermined pitch) and descending at individual processing points, for example, as shown in FIG.
And is generally employed in a so-called roughing process prior to finishing the material shape. In this case, if a part of the tool trajectory data of the tool is represented in a three-dimensional space, the trajectory is as shown in FIG. 20, for example.

Further, the applicant of the present application has priorly described a cutting method in which a tool is obliquely moved along a completed shape surface of the mold at a stroke end of the tool when the mold is cut out by punching. This is proposed in Japanese Patent Application Laid-Open No. H8-2443827.

[0005]

However, when a tool path is generated in the thrusting by the above-described conventional tool path data generation technology, in the actual thrusting operation until the completed shape of the target material is cut out, Unnecessary uncut portions (so-called islands) may occur on the material.

Further, when a so-called NC (numerical control) machining device or the like is performing a punching process at a predetermined pitch based on the generated tool trajectory data, a tool used at a certain point on the material is used. In some cases, overcutting is performed in an area exceeding the cutting ability of the tool, in which case the tool will be overloaded more than the allowable limit. Failure occurs.

Conventionally, when these situations occur,
Since the operator manually changes the automatically generated tool path data, the manufacturing efficiency is not improved even though the tool path is automatically generated.

Accordingly, an object of the present invention is to provide a tool trajectory generating apparatus, a tool trajectory generating method, and a computer-readable storage medium for generating an efficient tool trajectory by preventing the generation of unnecessary uncut portions. .

[0009]

Means for Solving the Problems In order to achieve the above object, a tool trajectory creating apparatus according to the present invention has the following configuration.

In other words, there is provided a tool trajectory creating apparatus for creating a tool trajectory for performing a cutting operation with a tool on a workpiece based on a shape model representing a product shape. Repeating the offset in the predetermined plane based on the edge line calculation means for calculating the edge line in the above, the edge line calculated by the edge line calculation means, and a predetermined amount set according to the tool diameter of the tool. A tool path creating means for creating at least two tool paths,
Of two adjacent tool trajectories created by the tool trajectory creating means, extracting a break point where a break point of an outer tool trajectory is smaller than a predetermined angle with respect to the edge line;
When the tool is moved at a predetermined pitch along the other tool path on the edge line side in a predetermined range including the break point, a processing limit position on the outer tool path side by the tool is obtained, and the processing limit position is obtained. Correction means for correcting the outer tool trajectory so as to be included in a machining area by the tool when the tool is moved at the predetermined pitch along the outer tool trajectory. .

Further, for example, the correcting means makes two perpendicular lines from the break point to the other tool path on the edge line side, and sets the range of the intersection between the tool path and the two perpendicular lines to the predetermined range. In the predetermined range, the intersection of two adjacent circles of a plurality of circular machining areas of the tool when the tool is moved at a predetermined pitch along the other tool trajectory is calculated. Of the two intersections, a straight line passing through the intersection on the edge line side and the center of one of the two adjacent circles intersects one of the circles, and the calculated point and the outside are calculated. A position that is at most the radius of the tool away from the point of the line segment connecting the tool trajectory with the shortest distance is set as the processing limit position, and includes all the processing limit positions based on the outer tool trajectory. The tool rail The better to correction.

Further, in order to achieve the above object, a tool path creating method according to the present invention has the following features.

In other words, there is provided a tool trajectory creating method for creating a tool trajectory for performing a cutting operation with a tool on a workpiece based on a shape model representing a product shape. An edge line calculating step of calculating an edge line in the above, and an offset in the predetermined plane is repeated based on the calculated edge line and a predetermined amount set according to a tool diameter of the tool, so that at least two A tool trajectory creating step of creating a tool trajectory, and extracting, from the created two adjacent tool trajectories, a break point at which a break point of an outer tool trajectory is smaller than a predetermined angle with respect to the edge line, When the tool is moved at a predetermined pitch along the other tool path on the edge line side in a predetermined range including a break point, Determine the processing limit position on the outer tool path side by the, so that the processing limit position is included in the processing area by the tool when moving the tool at the predetermined pitch along the outer tool path, And a correcting step of correcting the outer tool path.

In the correction step, for example, two perpendicular lines are set from the break point to the other tool path on the edge line side, and the range of the intersection between the tool path and the two perpendicular lines is defined as the predetermined range. In the predetermined range, the intersection of two adjacent circles of a plurality of circular machining areas of the tool when the tool is moved at a predetermined pitch along the other tool trajectory is calculated. Of the two intersections, a straight line passing through the intersection on the edge line side and the center of one of the two adjacent circles intersects one of the circles, and the calculated point and the outside are calculated. A position that is at most the radius of the tool away from the point of the line segment connecting the tool trajectory with the shortest distance is set as the processing limit position, and includes all the processing limit positions based on the outer tool trajectory. To It may correct the tool path.

Further, the present invention is characterized by a computer-readable storage medium for operating a computer as an apparatus for realizing the above-mentioned tool path creating apparatus.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a tool trajectory creating apparatus according to the present invention will be described below in detail with reference to the drawings.

First, a cutting tool employed in the present embodiment and a pushing operation by the tool will be described with reference to FIGS.

In this embodiment, as shown in FIGS. 1 and 2, as an example of a cutting tool, a tool 1 which is a so-called vertical mill is employed. Further, the cutting operation by the tool 1 is a so-called thrusting operation, and is a material (working object).
The edge line (edge shape) constituting the outer shape is subjected to a punching process while lowering the rotating tool 1 in the Z direction by a mechanism (not shown), and a predetermined amount of the punching process in the Z direction is performed. Upon completion, the tool 1 is returned in the -Z direction, and then, in the case of the examples of FIGS. A predetermined material shape is obtained by repeating this series of operations.

In this embodiment, since the tool 1 is a vertical mill having an end portion having a shape as shown in FIGS. 1 and 2, at a certain processing point, the edge shape of the tool 1 and the material Is, for example, FIG.
When the positional relationship is as shown in (1), an overload exceeding the cutting ability of the tool 1 is applied (hereinafter, such a state is referred to as an overload state), and appropriate punching cannot be performed. Also, in the case of the material to be machined, due to the positional relationship shown in FIG. 3, when the feed direction of the tool 1 gradually proceeds downward in FIG. As a result, it is difficult for the cut surface to be discharged, and this has an adverse effect on the cut surface. Therefore, it is necessary to generate a trajectory that does not cause such a positional relationship between the tool 1 and the edge shape of the material. In the present embodiment, a tool trajectory that does not generate such an overload state and an unnecessary uncut portion is created.

[Procedure for Creating Tool Trajectory] The procedure for creating a tool trajectory in the present embodiment will be described below with reference to FIGS.
This will be described with reference to FIG. These figures geometrically illustrate a method of creating a tool path in the present embodiment, and a tool path creation process that is actually performed by a tool path creation apparatus described later will be described later.

FIGS. 4 to 10 are views for explaining a procedure for creating a tool trajectory according to an embodiment of the present invention. FIG. Of the moving trajectory is viewed from above. With reference to these figures, a material having a predetermined shape to be used in a roughing process in the manufacture of a mold is used as a tool 1.
Tool 1 in the XY direction when punching by
Will be described in the following five steps.

<Step 1: Step of Defining Breakpoint> 1) First, as shown in FIG. 4, the radius R (=) of the tool 1 is determined based on the edge line EL corresponding to the completed shape of the die.
40mm) and finishing allowance D for finishing (= 2mm)
The base guideline BGL is obtained by offsetting by the amount obtained by adding. Here, the base guide line BGL represents the trajectory of the tool 1 in the X-Y direction at the time of the punching process for cutting out the final material shape in the roughing process.

It is needless to say that the finishing allowance D is not required when directly cutting the edge line EL.

2) Next, a guide line GL2 is obtained by offsetting a predetermined amount (= 75 mm) with respect to the base guide line BGL. Further, by repeating this predetermined amount of offset until the edge line OEL constituting the outer shape of the material before the start of the punching process is included, the (m-1) guide lines GL2 to GLm
Ask for.

Here, the predetermined amount at the time of offset should be smaller than twice the radius R of the tool 1 (80 mm in this case) to some extent so that an unnecessary material shape does not remain after machining. Set. By this, guideline GL
m, GL (m-1),. . . GL2 and then the base guideline BGL, in order of the tool 1
The material shape including the finishing margin D outside the edge line EL can be basically obtained by performing the punching. However, when the offset is simply performed by a predetermined amount, there is a case where a portion separated by more than twice the radius R of the tool 1 occurs in the adjacent trajectory (between the guide lines) due to the shape of the edge line EL. There is. For example, as shown in FIG.
Considering the case where the punching is performed at the overload position L on L and the break point B on the guide line GL2 (the overload position L and the break point B will be described later), the processing areas of the tool do not overlap. It can be seen that a portion (the uncut portion I) occurs. Therefore, by the following steps, FIG.
As an example, the guide line GL2 is corrected (trimmed) so that the uncut portion I does not occur. In the actual processing, the trimmed guideline GL2
Based on the guidelines GL3,. . . , Up to the guideline GLm.

3) In the guide line GL2, a point at which the bending angle of the guide line is smaller than a predetermined angle RB (= 160 °) (hereinafter, referred to as a point)
Is defined as a break point B. Here, the reason for extracting the break point B will be described. If the break angle of the guide line 2 is smaller than the predetermined angle RB, it means that the point (break point B) and the base guide line BG corresponding to the point
This is because the point on L is more than a predetermined amount, which indicates that uncut portions are left. Further, at such a position (overload position L), since the feed direction of the tool 1 changes abruptly, an overload state as shown in FIG. 3 occurs.

<Step 2: Defining step of overload area> Base guideline BGL from break point B extracted in step 1
In order to obtain two perpendiculars to, as shown in FIG.
A circle having a radius of the above-mentioned predetermined amount (= 75 mm) is created around the break point B, and intersections (CP1, CP2) between the circle and the base guideline BGL are obtained. The tool 1 is placed between CP1 and CP2 on the base guideline BGL.
Is defined as an overload area that will be overloaded.

<Step 3: Step of extracting limit position of punching in overload area> In this step, in the overload area between CP1 and CP2 defined in step 2, the tool 1 is moved at a predetermined pitch (= 14 mm). Guideline GL2 that allows cutting of tool 1 when moving and pushing
Side limit position PP (n) is determined.

1) First, a point CT (n) on the base guide line BGL when the tool 1 is moved at a predetermined pitch in the overload area is created. At this time, in order to obtain the intersection Pc1 in the following 3), the point CT1 is created at a position one pitch before the CP1.

2) Next, a circle Cr (n) having a radius equal to the tool radius R is created centering on each point of the point CT (n).

3) Next, among the intersections of the adjacent circles Cr (n), the intersection Pc (n) on the edge line EL side is obtained.

4) Next, as shown in FIG.
A straight line L (n) connecting (n) and the center of the circle Cr (n) including the intersection is created, and an intersection PP (n) of the straight line and the circle Cr (n) on the guide line GL2 side is determined.

<Step 4: Step of Setting Punching Point to Avoid Generation of Limiting Position of Punching Process> In this step, the limit position PP (n) of the punching process obtained in Step 3 is determined in the actual punching process. In order to avoid the occurrence, that is, in the vicinity of the guideline GL2, the limit position PP (n) is included in the area to be pierced by the tool 1 when the movement and piercing of the tool 1 are performed according to the guideline GL2. Is obtained.

1) First, as shown in FIG.
A line segment LL (n) connecting P (n) and the guide line GL2 at the shortest distance is created.

2) Next, a position Px (n) on the line segment LL (n) and separated from the limit position PP (n) by a tool radius R (of course, it may be slightly shorter than R).
Ask for.

<Step 5: Trim Step of Guideline Based on Set Avoidance Punch Point> In this step, the guideline GL2 is trimmed based on the position Px (n) obtained in Step 4. The trim method described below is an example. For example, when connecting the position Px (n), a predetermined arc and a line segment may be combined.

1) First, as shown in FIG.
(N) is set, and a rectangle having B1, B2, B3, and B4 as vertices is set.

2) Next, among the four vertices of the rectangle, a point farthest from the break point B is selected, and the selected point is used as a starting point and includes all positions Px (n) based on the guide line GL2. A line (a broken line connecting Px2 and PX1 with Px3 as a fulcrum in the example of FIG. 9) is created.

3) Next, a circle having a predetermined radius (in the present embodiment, twice the predetermined pitch of the tool 1) is created around the break point B, and an intersection G between the circle and the guide line GL2 is created.
1, G2 is determined. Here, the reason why the predetermined radius is set to twice the predetermined pitch of the tool 1 is that if a circle having such a radius is set, the start point and the end point of the polygonal line created in the above 2) intersect G1 and G2. Because it can be connected smoothly.

4) The intersection points G1 and G2 are connected to the start point and the end point of the polygonal line created in 2), respectively.

5) By deleting the area between G1 and G2 on the guide line GL2, the trimmed guide line GL2 shown by a solid line in FIG. 10 is obtained. As can be seen from a plurality of circles shown in FIG. 10 that indicate the area where the tool 1 performs the punching at a predetermined pitch in the XY direction, the base guideline BG
It can be seen that if the punching is performed by the tool 1 at a predetermined pitch in accordance with L and the guide line GL2 after trimming, the generation of the uncut portion I shown in FIG. 4 can be prevented.

The procedure from Step 1 to Step 5 described above is
Guidelines GL3,. . . Trim is performed by sequentially performing the operation on the guideline GLm. Then, in actual punching, if the tool 1 is moved in the order of the guideline GLm to the guideline GL2 and then to the base guideline BGL to perform the punching, unnecessary uncut portions are prevented from occurring and an overload state is prevented. Thus, an efficient tool path can be generated. Accordingly, since the occurrence of an overload state can be prevented in the thrusting by the tool 1, the adverse effect due to the chips of the material on the cutting surface can also be prevented.

[Tool Path Creation Apparatus] Next, the hardware configuration of the tool path creation apparatus according to the present embodiment will be described.

FIG. 11 is a block diagram of a tool trajectory creating apparatus according to an embodiment of the present invention. For example, a personal computer may be used.

In the figure, reference numeral 22 denotes a display such as a CRT. Reference numeral 23 denotes a keyboard as an input unit. 24
Is a ROM storing a boot program and the like.
Reference numeral 25 denotes a RAM for temporarily storing various processing results. 2
6 corresponds to, for example, a three-dimensional shape data file as a mold shape model created in advance in an external device, a program that implements a tool path creation process described later, and a tool path created by the tool path creation process. A storage device such as a hard disk drive (HDD) for storing a program for creating so-called NC data. 2
Reference numeral 7 denotes a communication interface for communicating with an external device via the communication line 30. Reference numeral 28 denotes a printer that prints processing results and the like. These components are connected via an internal bus 29, and the CPU 21 controls the entire tool trajectory creating device according to a program stored in the storage device 26.

The tool trajectory data calculated by the tool trajectory creating device is converted into NC data by a general method, and the NC data is transmitted via a communication line 30 to an NC (Numerical Control) (not shown). It is transferred to a processing device or the like, and the NC processing device performs cutting or the like using the transferred NC data.

[Tool Path Creation Processing] Next, the tool path creation processing according to the present embodiment will be described with reference to the flowcharts shown in FIGS. The following flowchart is a process executed by the CPU 21 of the tool path creation device in FIG.

First, an overall outline of a tool path creation process in the tool path creation apparatus will be described.

FIG. 12 is a flow chart showing an outline of the tool trajectory creation processing in one embodiment of the present invention. In the figure, step S1: a mold shape model (material shape after processing) and three-dimensional CAD data of a material shape before processing are read in advance in an external device.

Step S2: Based on the read three-dimensional CAD data, the edge line EL and the edge line OEL of the die shape and the material shape before processing are represented on the XY plane to be cut by the punching process. Generate. In the present embodiment, a finishing allowance D is also set in order to create a tool path in the rough machining process.

Here, the edge line EL and the edge line OEL are functions represented by a set of line elements such as a plurality of line segments, spline lines, and arcs (hereinafter, referred to as “line segments”) obtained based on three-dimensional coordinate values. Composite curve) and 2
It can be handled as dimensional shape data.

Step S3: 2 which is the basis of trim processing
Create multiple dimensional tool paths. That is, the edge line E
The edge line O is obtained by repeating a predetermined amount of offset between the base guide line BGL and a plurality of guide lines GLm for shaving a shape including the finishing allowance D in L.
Generate until EL is included.

Here, the base guide line BGL and the plurality of guide lines GLm are also composite curves.

Step S4: Trim processing is performed on the plurality of guide lines GLm (tool trajectories) generated in step S3 in order to avoid the occurrence of an overload state and an uncut portion.

Step S5: Base guideline BGL
And each guideline GL2 trimmed in step S4
Since GLm is a composite curve that is a set of line elements, these tool trajectory data are converted into the composite curve data, the Z-direction data included in the three-dimensional shape data read in step S1, and the tool 1
For example, based on the data representing the stroke length of, the trajectory is converted into a three-dimensional actual thrust trajectory in the XYZ space as shown in FIG.

Next, step S3 and step S3 are performed.
4 will be described in detail.

FIG. 13 is a flowchart showing a process of creating a plurality of basic two-dimensional tool trajectories in the tool trajectory creation process according to one embodiment of the present invention, and shows the details of step S3. In the figure, step S31: edge line EL and predetermined finishing allowance D
Guideline BGL for cutting out shapes including
Create

Step S32: Base guideline BG
By repeating a general predetermined amount of offset processing based on L, a plurality of guidelines GLn are generated until the edge line OEL is included.

FIG. 14 is a flowchart showing the trimming process for the guide line GL in the tool trajectory creating process in one embodiment of the present invention.
4 is shown in detail. In the figure, step S41: currently targeted guideline GL
n (the guideline GL2 in the example of FIG. 4)
Each line element constituting the guideline GLn, which is a composite curve, is calculated by a general vector inner product calculation, and as a result of the calculation, a point smaller than a predetermined angle is defined as the X and Y coordinate values of the break point B. This step corresponds to step 1 described above.

Step S42: An equation representing a circle having a predetermined radius centered on the coordinate value of the break point B, and a guide line G
L (n-1) (in the example of FIG. 4, the base guideline BG
By calculating intersections CP1 and CP2 with L), the area between CP1 and CP2 is defined as an overload area. This step corresponds to step 2 described above.

Step S43: Overload area CP1-C
The limit position of the punching operation between P2 is calculated. Details will be described with reference to FIG. This step corresponds to step 3 described above.

Step S44: Calculate a point for avoiding occurrence of the limit position of the punching operation. Details will be described with reference to FIG. This step corresponds to step 4 described above.

Step S45: The guideline GL currently targeted is trimmed based on the avoidance point calculated in step S44. Details will be described with reference to FIG. This step corresponds to step 5 described above.

FIG. 15 is a flowchart showing a process for calculating the limit position of the punching process in the trimming process for the guide line GLn in one embodiment of the present invention, and shows the details of the step S43. In the figure, Step S431: Guideline G currently targeted
From the points when the tool 1 is moved at a predetermined pitch along Ln, a plurality of points CT (n) included in a range from CP1 to CP2 are extracted.

Step S432: Each point CT (n)
Is generated, and the intersection Pc (n) of the two adjacent circles is calculated by generating the equation of a circle Cr (n) having a tool radius R and solving the equation of two adjacent circles.

Step S433: Equation L (n) of a straight line connecting intersection Pc (n) on circle Cr (n) and Cr (n) corresponding to CT (n-1), which is the center of the circle. Generate

Step S434: Linear equation L (n)
And the solution of the equation of the circle Cr (n) is obtained, and the intersection PPn on the guideline GLn side currently targeted is calculated.

FIG. 16 is a flow chart showing a point setting process for avoiding the occurrence of the limit position of the punching process in the trimming process for the guide line GLn according to the embodiment of the present invention, and shows the details of the step S44. In the figure, Step S441: Guideline G currently targeted
The equation of a line segment LL (n) connecting Ln and the intersection PPn at the shortest distance is calculated. The point on the guide line GLn, which is located at the shortest distance from the intersection point PPn, may be calculated using the X and Y coordinate values of a point near the break point B included in the composite curve representing the guide line GLn.

Step S42: The position Px (n) of the tool radius R on the line segment LL (n) is calculated from the intersection PPn, and the calculated position Px (n) is used as a point for avoiding the occurrence of the punching limit position ( Avoidance point).

FIG. 17 is a flowchart showing the trimming process based on the avoidance point, of the trimming process for the guideline GLn in one embodiment of the present invention.
The details of the above step S45 will be described. In the figure, step S451: a rectangle including all the coordinate values of the position Px (n) and having vertices B1, B2, B3, and B4 is set, and the distance between the four vertices of the rectangle and the break point B is calculated. And select the point with the longest distance.

Step S452: Starting from the point selected in step S451, a polygonal line (column of line elements) which is the outermost contour is created based on the position Px (n) based on the currently targeted guideline GLn. Which point is connected to become the outermost contour may be obtained by calculating the inner product of the vectors.

Step S453: Intersections G1 and G2 between the guideline GLn currently targeted and the equation of a circle having a predetermined radius centered at the break point B are obtained.

Step S454: A line element connecting the intersections G1 and G2 and the start and end points of the polygonal line obtained in step S452 is obtained.

Step S455: G1 included in the composite curve of the guideline GLn currently targeted
The line element between -G2 is changed from step S452 to step S452.
The composite curve of the guide line GLn after trimming is obtained by replacing with a plurality of line elements constituting the polygonal line obtained in the steps up to 454.

It should be noted that the above-described embodiment is shown in FIGS.
7 is stored in a storage medium such as a floppy disk, and the information in the storage medium is read into, for example, a personal computer. It is needless to say that the present invention can be applied to a case of operating as a trajectory creating device.

In the above-described embodiment, the processing from the three-dimensional tool trajectory data to the creation of the NC data is performed as the tool trajectory generating apparatus. However, the present invention is not limited to this. May be provided integrally with the device. Alternatively, it goes without saying that the tool trajectory creating device may perform up to creation of two-dimensional tool trajectory data in the X-Y direction or creation of three-dimensional tool trajectory data including the amount of thrust stroke in the Z direction. No.

In the above-described embodiment, a vertical mill is used as the tool 1. However, the present invention is not limited to this. For example, a cutting tool such as a ball end mill may be used. However, in such a case, it goes without saying that the positional relationship between the edge line of the material and the cutting tool, the definition of the overload state, and the like should be changed as appropriate.

[0078]

As described above, according to the present invention,
A tool trajectory creation device, a tool trajectory creation method, and a computer-readable storage medium that prevent generation of unnecessary uncut portions and generate an efficient tool trajectory are realized.

That is, according to the first, ninth and eleventh aspects of the present invention, it is possible to prevent the generation of an unnecessary uncut portion, and to automatically and efficiently generate a tool path. be able to.

According to the second and tenth aspects of the present invention, when the tool moves along the outer tool trajectory, it is included in the machining area of the tool in order to avoid the occurrence of unnecessary uncut portions. The processing limit positions to be set and the trajectory based on those positions can be easily corrected.

According to the third aspect of the present invention, an unnecessary part of the uncut portion of a plurality of tool trajectories from the shape of the object to be processed (raw material) before machining to the product shape (die) is machined. It can be corrected so that it does not occur, and by sequentially performing machining according to these corrected tool paths,
Failure of the tool and the material can be prevented.

According to the invention of claim 4, for example, N
A tool trajectory for actually moving a tool in a three-dimensional space, which is used in a C processing device or the like, can be easily obtained.

According to the fifth aspect of the present invention, since the edge line and the tool trajectory are treated as a set of a plurality of line elements, the amount of calculation in the tool trajectory creating apparatus can be changed to the coordinate values of a plurality of point groups. The number of operations can be reduced as compared with the case of handling, and calculation speed, angle calculation, and the like can be performed quickly.

[0084]

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a relationship between a tool and a material shape of an object to be processed by the tool according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a relationship between a tool and a material shape of an object to be processed by the tool according to the embodiment of the present invention.

FIG. 3 is a diagram illustrating a case where a positional relationship between a tool and a material shape of a processing object is in an overload state in one embodiment of the present invention.

FIG. 4 is a diagram illustrating a procedure for creating a tool path as one embodiment of the present invention.

FIG. 5 is a diagram illustrating a procedure for creating a tool path as one embodiment of the present invention.

FIG. 6 is a diagram illustrating a procedure for creating a tool path according to an embodiment of the present invention.

FIG. 7 is a diagram illustrating a procedure for creating a tool path as one embodiment of the present invention.

FIG. 8 is a diagram illustrating a procedure for creating a tool path as one embodiment of the present invention.

FIG. 9 is a diagram illustrating a procedure for creating a tool path as one embodiment of the present invention.

FIG. 10 is a diagram illustrating a procedure for creating a tool path as one embodiment of the present invention.

FIG. 11 is a block diagram of a tool trajectory creating apparatus as one embodiment of the present invention.

FIG. 12 is a flowchart illustrating an outline of a tool path creation process according to an embodiment of the present invention.

FIG. 13 is a flowchart illustrating a process of creating a plurality of basic two-dimensional tool trajectories in the tool trajectory creation process according to the embodiment of the present invention.

FIG. 14 is a flowchart illustrating a trimming process for a guide line GL in the tool path creating process according to the embodiment of the present invention.

FIG. 15 is a guideline G in one embodiment of the present invention.
It is a flowchart which shows the calculation process of the punching limit position among the trim processes with respect to Ln.

FIG. 16 is a guideline G in one embodiment of the present invention.
It is a flowchart which shows the point setting process which avoids generation | occurrence | production of a punching limit position among the trim processes with respect to Ln.

FIG. 17 is a guideline G in one embodiment of the present invention.
It is a flowchart which shows the trimming process based on the avoidance point among the trimming processes for Ln.

FIG. 18 is a perspective view showing an example of a material shape before processing.

FIG. 19 is a perspective view showing an example of a material shape after a punching process.

FIG. 20 is a diagram showing an example of a tool trajectory for performing punching.

[Explanation of symbols]

 1: tool, 21: CPU, 22: display, 23: keyboard, 24: ROM, 25: RAM, 26: storage device, 27: communication interface, 28: printer, 29: internal bus, 30: communication line,

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Mataharu Okada 3-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda F-term (reference) 5H269 AB01 AB05 AB19 BB03 CC02 DD01 FF07 QC01 QC06 QD03 QD06

Claims (11)

[Claims] 1. A tool trajectory creating apparatus for creating a tool trajectory for performing a cutting operation on a workpiece by a tool based on a shape model representing a product shape, the tool trajectory creating device comprising: a predetermined plane of the shape model representing the product shape; Edge line calculation means for calculating the edge line in the above, and the offset in the predetermined plane is repeated based on the edge line calculated by the edge line calculation means and a predetermined amount set according to the tool diameter of the tool. A tool trajectory creating means for creating at least two tool trajectories, and a break point of an outer tool trajectory of the two adjacent tool trajectories created by the tool trajectory creating means is determined based on the edge line. Extract break points smaller than the angle,
When the tool is moved at a predetermined pitch along the other tool path on the edge line side in a predetermined range including the break point, a processing limit position on the outer tool path side by the tool is obtained, and the processing limit position is obtained. Correction means for correcting the outer tool trajectory so as to be included in a machining area by the tool when the tool is moved at the predetermined pitch along the outer tool trajectory. Tool path creation device. 2. The correction means sets two perpendicular lines from the broken point to the other tool path on the edge line side, and sets a range of an intersection point between the tool path and the two perpendicular lines as the predetermined range. In the predetermined range, the intersection of two adjacent circles of a plurality of circular machining areas of the tool when the tool is moved at a predetermined pitch along the other tool path is calculated. Intersections on the edge line side among the intersections,
A straight line passing through the center of one of the two adjacent circles intersects with one of the circles, and calculates a point where the calculated point and the outer tool path are connected at the shortest distance. A position that is at most a radius of the tool away from the point is set as the processing limit position, and the tool trajectory is corrected so as to include all the processing limit positions with reference to the outer tool trajectory. The tool path creation device according to claim 1. 3. The tool trajectory creating means creates a plurality of tool trajectories from the shape of the workpiece before machining to the product shape by repeating the offset, and wherein the correcting means comprises: Of the plurality of tool trajectories, the outer tool trajectory is corrected between a tool trajectory closest to the edge line and an outer tool trajectory adjacent to the tool trajectory. 2. The tool path creating device according to claim 1, wherein all of the plurality of tool paths are corrected by sequentially correcting the outer tool paths that match. 4. A conversion device for converting a tool trajectory on the predetermined plane corrected by the correction device into a tool trajectory in a three-dimensional space based on a stroke length of the tool and the shape model. The tool path creation device according to claim 1, wherein 5. The tool path creating device according to claim 1, wherein the edge line and the tool path are a set of a plurality of line elements. 6. The cutting method according to claim 1, wherein, in the cutting, the tool alternately repeats a moving operation at a predetermined pitch in accordance with the tool path and a thrusting operation at the moved point. Tool path creation device. 7. The apparatus according to claim 1, wherein the tool is a vertical mill. 8. The apparatus according to claim 1, wherein the shape model is three-dimensional shape data of a mold. 9. A tool trajectory creating method for creating a tool trajectory for performing a cutting process with a tool on a workpiece based on a shape model representing a product shape, comprising: a predetermined plane of the shape model representing the product shape; An edge line calculating step of calculating an edge line in the above, and an offset in the predetermined plane is repeated based on the calculated edge line and a predetermined amount set in accordance with a tool diameter of the tool, so that at least two A tool trajectory creating step of creating a tool trajectory, and extracting, from the created two adjacent tool trajectories, a break point at which a break point of an outer tool trajectory is smaller than a predetermined angle with respect to the edge line, When moving the tool at a predetermined pitch along the other tool path on the edge line side in a predetermined range including a break point, The processing limit position on the outer tool trajectory side is determined, and the processing limit position is included in a processing area of the tool when the tool is moved at the predetermined pitch along the outer tool trajectory. A correction step of correcting an outer tool path. 10. In the correcting step, two perpendicular lines are made from the break point to the other tool path on the edge line side, and a range of an intersection between the tool path and the two perpendicular lines is defined as the predetermined range. In the predetermined range, the intersection of two adjacent circles of a plurality of circular machining areas of the tool when the tool is moved at a predetermined pitch along the other tool path is calculated. Intersections on the edge line side among the intersections,
A straight line passing through the center of one of the two adjacent circles intersects with one of the circles, and calculates a point where the calculated point and the outer tool path are connected at the shortest distance. A position that is at most a radius of the tool away from the point is set as the processing limit position, and the tool trajectory is corrected so as to include all the processing limit positions with reference to the outer tool trajectory. The method according to claim 9. 11. A computer-readable storage medium storing a program for a tool trajectory creating process for creating a tool trajectory for performing a cutting operation by a tool on a workpiece based on a shape model representing a product shape. The storage medium for causing a computer to calculate an edge line on a predetermined plane of the shape model representing the product shape, an edge line calculation unit, an edge line calculated by the edge line calculation unit, and a tool diameter of the tool. A tool trajectory creating means for creating at least two tool trajectories by repeating the offset in the predetermined plane based on the predetermined amount set in the above-mentioned manner, and two adjacent tools created by the tool trajectory creating means Of the trajectories, the break point of the outer tool trajectory with respect to the edge line Extract a smaller break point,
When the tool is moved at a predetermined pitch along the other tool path on the edge line side in a predetermined range including the break point, a processing limit position on the outer tool path side by the tool is obtained, and the processing limit position is obtained. Is operated as correction means for correcting the outer tool trajectory so as to be included in a machining area by the tool when the tool is moved at the predetermined pitch along the outer tool trajectory. Storage media.