JP2001034318A - Method for preparing working pass, method for automatically preparing nc program, cad/cam system, nc working system, and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To evade the interference of a tool at an entering or escaping operation of the tool. SOLUTION: A safety boundary 19 in which a target to be worked 16 and a tool 18 do not interfere with each other is prepared on the basis of the maximum rotational radius K of the target 16 at the time of working the target 16 and the entering operation and escaping operation of the tool 18 into/from the target 16 are determined on the basis of working model data and the safety boundary 19 to prepare a working pass.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the creation of an NC program for an NC controlled machine tool, and more particularly to a machining path creating method for creating an NC program for avoiding interference between a workpiece and a tool, and this machining path. The present invention relates to an NC program automatic creation method for creating an NC program based on a program, a CAD / CAM system to which a machining path creation method is applied, an NC machining system, and a storage medium for storing a machining path creation method program.

[0002]

2. Description of the Related Art In a manufacturing process of a product such as a mold, a three-dimensional CAD / CAM system is used. First, a product is designed in a three-dimensional CAD, and three-dimensional model data of the product is created. Pass to.

In the three-dimensional CAM, the three-dimensional model data from the three-dimensional CAD is received, and NC machining conditions are input. Based on the three-dimensional model data and the NC machining conditions, the machining path of the tool of the NC machine tool is determined. Then, an NC program corresponding to various NC machines is created from this machining path.

An NC processing machine receives an NC program from a three-dimensional CAD / CAM system through a data transfer system, and performs processing on a workpiece according to the NC program. This NC machine has, for example, four tools.
Some have more axes than axes (X axis, Y axis, Z axis, and rotation axis), and these axes are simultaneously controlled to process a workpiece.

In such an NC machine having four or more axes, a workpiece is machined by moving a tool along a machining path while rotating the workpiece, but not during cutting of the workpiece. In addition, it is necessary to avoid interference between the workpiece and the tool, and an NC program has been created.

As a method of creating an NC program for avoiding the interference between a workpiece and a tool for such an NC machine having four or more axes, for example, in a human system, a clearance of a tool is determined by, for example, a division amount. There is a method of setting the height and a method of using a tool movement method (plane movement) for three-axis machining that does not consider the rotation axis.

[0007]

However, in the above-mentioned method of creating each NC program, since the shape of the workpiece (material model) before machining is not taken into consideration, the approach operation of the tool to the machining start point is performed. In this case, interference of the tool with the workpiece occurs.

In the method of moving a tool in a plane, a collision of the moving tool with a rotating workpiece occurs.

In order to cause such interference of the tool with the workpiece, it is necessary to set a longer approach distance of the tool before cutting and an escape distance of the tool after cutting.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for creating a machining path which can avoid interference of a tool in a tool entry or escape operation.

Another object of the present invention is to provide an NC program automatic creation method capable of avoiding interference of a tool in a tool entry or escape operation.

Also, the present invention provides a CAD / C for creating a machining path capable of avoiding interference of a tool in a tool entry or escape operation.
It is intended to provide an AM system.

Another object of the present invention is to provide an NC machining system capable of performing NC machining while avoiding interference of a tool in a tool entry or escape operation.

Another object of the present invention is to provide a program for creating a machining path capable of avoiding interference of a tool in a tool entry or escape operation or a storage medium for storing an NC program created from the machining path. .

[0015]

A machining path creating method according to the present invention creates a tool machining path in an NC machine for machining a workpiece with reference to three-dimensional model data. A step of obtaining a safety boundary where the workpiece does not interfere with the tool based on a range required for the workpiece to move during processing of the workpiece, and a step of creating a processing path based on the three-dimensional model data and the safety boundary And

The above-mentioned machining path creation method comprises the steps of obtaining a maximum radius of gyration, which is the position of the outermost rotation locus of the workpiece when the workpiece is rotated, and based on the maximum radius of gyration and the radius of the tool. The method includes a step of obtaining a safe rotation radius at which the workpiece and the tool do not interfere with each other, and a step of obtaining a cylindrical surface determined by the safe rotation radius as a safety boundary.

The above-mentioned machining path creation method comprises the steps of obtaining each radius of gyration at each cross section of the workpiece in the direction of the rotation axis when the workpiece is rotated; Determining each safety boundary.

The above-mentioned machining path creation method comprises the steps of obtaining each radius of gyration at each cross section of the workpiece in the direction of the rotation axis when the workpiece is rotated; A step of determining each safety boundary; and a step of determining a safety boundary surface including the workpiece from the safety boundaries.

The above-mentioned machining path creating method has a step of changing the position of the safety boundary by following a radius of rotation when rotating the workpiece which is reduced by the processing on the workpiece.

The above-described machining path creation method includes a step of determining whether the machining origin of the tool is set outside the safety boundary, and shifting to creating a machining path.

The above-mentioned machining path creation method includes a step of determining whether to select a material model having a shape approximate to the three-dimensional model or a material model having a predetermined shape based on the three-dimensional model data, A safety boundary is created for the workpiece selected in this step.

The method for automatically creating an NC program according to the present invention includes the step of creating an NC program for controlling an NC machining machine based on a machining path in each of the machining path creating methods described above.

A CAD / CAM system according to the present invention creates a machining path of a tool in an NC machine for machining a workpiece by a CAM according to three-dimensional model data created in the CAD. Boundary creation means for creating a safety boundary where the workpiece and the tool do not interfere with each other based on the moving space of the workpiece at the time of machining, and entry of the tool into the workpiece based on the three-dimensional model data and the safety boundary Machining path creating means for creating a machining path by determining the operation and the escape operation.

The CAD / CAM system safety boundary creating means includes: a maximum turning radius calculating means for obtaining a maximum turning radius that is an outermost rotation locus position of the workpiece when the workpiece is rotated; A safe turning radius calculating means for obtaining a safe turning radius in which the workpiece and the tool do not interfere with each other based on the turning radius and the radius of the tool, and a cylindrical surface determined by the turning radius obtained by the safe turning radius calculating means as a safety boundary. And a safety boundary calculation means.

The CAD / CAM system safety boundary creating means includes: a turning radius calculating means for obtaining each turning radius at each cross section of the work in the rotation axis direction when the work is rotated; Safety boundary calculation means for obtaining each safety boundary in each cross section of the workpiece from each rotation radius obtained by the calculation means.

The CAD / CAM system safety boundary creating means includes: a turning radius calculating means for calculating each turning radius at each cross section of the work in the rotation axis direction when the work is rotated; Safety boundary calculation means for obtaining each safety boundary in each section of the workpiece from each radius of gyration obtained by the calculation means, and a safety boundary surface including the workpiece from each safety boundary obtained by the safety boundary calculation means And safety boundary surface calculation means for determining

The CAD / CAM system has a safety boundary changing means for changing the position of the safety boundary by following the radius of rotation when rotating the work, which is reduced by processing the work.

The CAD / CAM system has a machining origin setting means for judging whether the machining origin of the tool is set outside the safety boundary and, if the machining origin is set outside the safety boundary, moving to the creation of a machining path. .

The CAD / CAM system includes material model selecting means for determining whether to select a material model having a shape approximate to the three-dimensional model or a material model having a predetermined shape based on the three-dimensional model data. Have.

Each of the CAD / CAM systems has an NC program creating means for creating an NC program for NC controlling the NC machine based on the machining path.

The NC processing system according to the present invention comprises a CA
CA according to the three-dimensional model data created in D
A processing path for processing the workpiece is created by M, and an NC program based on the processing path is provided. The workpiece and the tool are formed based on the movement space of the workpiece during the processing of the workpiece. A safety boundary that does not interfere with the safety boundary is created, and an NC program based on a machining path based on the safety boundary is provided.

A storage medium according to the present invention stores a program for each of the above-described machining path creation methods.

A storage medium according to the present invention stores a program for the NC program automatic creation method.

[0034]

(1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an overall configuration diagram of an NC machining system to which a three-dimensional CAD / CAM system is applied.

The three-dimensional CAD / CAM system 1 creates three-dimensional model data and creates a machining path based on the three-dimensional model data and machining conditions. Have.

An NC program database 5, a host processor 6, and an NC program server 7 are connected to the three-dimensional CAD / CAM system 1.
Each of the data transfer systems (D
NC) Various NC processing machines 9-1 to 9-1 through 8-n
9-n are connected.

The three-dimensional CAD 2 converts machining model data of a three-dimensional model (hereinafter referred to as a machining model) indicating the shape of a product, ie, a workpiece designed by an input operation by an operator, into machining in the database 4 shown in FIG. It has a function of storing in the model area 4a.

This database 4 has a machining model area 4
a, a material model area 4b, a tool information area 4c, a machining condition area 4d, a safety boundary area 4e, and a machining path area 4f.
And a control program area 4g.

In the material model area 4b, machining model data of predetermined various shapes, machining model data of already designed products, and material models such as square pillars and cylinders which are materials to be processed before being processed. Data is stored.

In the tool information area 4c, each NC processing machine 9 input by the operator's operation on the three-dimensional CAM 3
Information of each tool attached to -1 to 9-n, for example, the type of tool, for example, a tool is a Φ40 flat end mill, a tool radius R: 20 mm, a blade length: 150 mm, a holder diameter, and the like.

In the machining condition area 4d, machining conditions input by an operator's operation on the three-dimensional CAM 3, for example, machining surface, machining method,
The connection method of the machining path, the cutting feed distance before and after the machining, the tool entry method, the tool release method are stored, and the rotation speed of the spindle of each of the NC processing machines 9-1 to 9-n, the cutting feed speed, the cutting speed, and the like are stored. It is memorized.

The safety boundary area 4e stores safety boundary data created by the three-dimensional CAM 3 so that the workpiece does not interfere with the tool.

The processing path created in the three-dimensional CAM 3 is stored in the processing path area 4f.

The control program area 4g has a three-dimensional CA
A control program for operating the D2 and the three-dimensional CAM 3 is stored in advance. That is, a safety boundary where the workpiece and the tool do not interfere with each other is created based on the movement space of the workpiece during the processing of the workpiece, and the tool enters the workpiece based on the three-dimensional model data and the safety boundary. A machining path creation program for creating a machining path by determining the operation and the escape operation is stored. More specifically, a maximum rotation radius that is the outermost rotation locus position of the workpiece when the workpiece is rotated is determined, and the workpiece and the tool are determined based on the maximum rotation radius and the radius of the tool. This is a program for creating a machining path for finding a safe turning radius that does not interfere with the above, and obtaining a cylindrical surface determined by this safe turning radius as a safe boundary.

FIG. 3 shows a functional block diagram of the three-dimensional CAM. The three-dimensional CAM 3 receives the machining model created by the three-dimensional CAD 2 and stored in the machining model area 4a of the database 4 and the machining conditions stored in the machining condition area 4d, and based on these machining models and machining conditions. It has a function of creating a machining path. Specifically, as shown in FIG. 3, a safety boundary creating means 10, a machining path creating means 11, a safety boundary changing means 12, a machining origin setting means 1
3 and the functions of the material model selecting means 14.

As shown in the machining model 15 and the material model (workpiece) 16 of the steam turbine blade in FIG. 4 and the machining path creation order in FIG. And the tool 1 based on the moving space 17 of the workpiece 16 at the time of machining, that is, the moving space 17 having a radius K when rotated about the X axis as a rotation axis.
8 has a function of creating a safety boundary 19 that does not interfere with the safety boundary 8.

More specifically, the maximum turning radius calculating means 10 for obtaining the maximum turning radius K at the position of the outermost rotation locus of the workpiece 16 when the workpiece 16 is rotated about the X axis as the rotation axis. −1 and the maximum rotation radius K, the radius R of the tool 18 and the offset value V,
A safe turning radius calculating means 10-2 for obtaining a safe turning radius S S = maximum turning radius K + radius R + offset value V (1), and a rotation obtained by the safe turning radius calculating means 10-2. Radius S
(= K + R + V) and has a function with the safety boundary calculation means 10-3 for obtaining the cylindrical surface as the safety boundary 19 described above.

The rotation radius S actually used is the rotation radius (S + α), and the position of the tool 18 is separated from the workpiece 16 by this positive α value. This is because the tool 18 may come into contact with the workpiece 16 with only the turning radius S.

The machining path creating means 11 includes a three-dimensional CAD 2
Model data and safety boundary creating means 1 created in
It has a function of determining the approach operation and the escape operation of the tool 18 with respect to the workpiece 16 based on the safety boundary 19 created at 0 and creating a machining path.

The safety boundary changing means 12 changes the position of the safety boundary 19 following the turning radius K when the work 16 which is reduced by cutting the work 16 is rotated about the X axis as the rotation axis. It has a function to make it work.

The machining origin setting means 13 has a function of judging whether the machining origin of the tool 18 is set outside the safety boundary 19, and if it is set outside the safety boundary 19, has a function of moving to the creation of a machining path. I have.

The material model selection means 14 is a three-dimensional CAD
2. From the material models stored in the material model area 4b of the database 4 based on the machining model data created in Step 2, select a material model having a shape similar to the machining model created by three-dimensional CAD 2, or select a predetermined shape. Has a function of determining whether or not to select a material model.

The host processor 6 receives the machining path created by the three-dimensional CAM 3 and performs NC control for controlling the NC machines 9-1 to 9-n based on the machining path.
It has a function as an NC program creating means for creating a program and storing it in the NC program database 5.

The NC program server 7 receives the NC programs created by the host processor 6 and stored in the NC program database 5, and converts the NC programs into NC programs corresponding to various NC processing machines 9-1 to 9-n. To the data transfer system 8-1
To the various NC machines 9-1 to 9-n through.

Next, regarding the operation of creating a machining path by the NC machining system configured as described above, a case where steam turbine blade machining is performed using an NC machine 9-1 having four axes (XYZ axes, rotation axes). Will be described with reference to the flowchart of the machining path creation procedure shown in FIGS.

First, in the three-dimensional CAD 2, step # 1
, A product, that is, a three-dimensional machining model 15 of the shape of a steam turbine blade is designed by an interactive input operation by an operator, and the machining model data is sent to the database 4. This machining model data is stored in the three-dimensional model data area 4a in the database 4.

Next, in step # 2, the three-dimensional CAM 3 sets the rotation axis around the X-axis to A, as shown in FIGS.
A machine coordinate system A (X, Y, Z) is set as shown in FIG.
That is, the origin of the machine coordinate system A (X, Y, Z) is set to G
(0,0,0,0), and the workpiece 16 has the axis GG ′
Is set to rotate around the axis. FIG. 4 shows the positional relationship of the processing origin P1 (0, 0, 300, 0).

Next, in step # 3, the NC processing machine 9 for the three-dimensional CAM 3 is operated by the operator.
-1 information on each of the tools 18 attached, for example, tool 1
Eight types, for example, Φ40 flat end mill, tool radius R: 20 mm, blade length: 150 mm, holder diameter, etc. are input as tools. This tool information is stored in the tool information area 4c in the database 4.

Next, in step # 4, the three-dimensional CAM 3 waits for an operation input as to whether or not to create a new material model by the operation of the operator.

If a new material model is to be created, the material model selecting means 14 of the three-dimensional CAM 3 proceeds to step # 5 to create a new material model.
Material model data of, for example, a square pillar or a cylinder is read from the material model area 4b in the database 4 and displayed on a monitor.

When the operator selects a material model of, for example, a square pillar, ie, a workpiece 16 shown in FIG. 4 from the material models displayed on the monitor, the three-dimensional CAM is obtained.
In step # 6, a work piece 16 having a quadrangular prism is read from the material model area 4b in the database 4 in step # 6.

Next, in steps # 7 and # 11, the safety boundary creating means 10 of the three-dimensional CAM 3 rotates the workpiece 16 about the X axis as the rotation axis as shown in FIGS. A safety boundary 19 where the workpiece 16 and the tool 18 do not interfere with each other based on the moving space 17 having the maximum turning radius K.
Create

The safety boundary creating means 10 of the three-dimensional CAM 3 inputs an extra thickness t as an offset value V between the machining model 15 and the workpiece 20 by an operation of the operator.

Creation of Safety Boundary 19 FIGS. 4 and 5
First, the maximum turning radius calculating means 1 will be described.
0-1 detects the rotation trajectory of the point D which is the farthest point when the workpiece 16 is arranged on the X axis, that is, the point D when the workpiece 16 is rotated around the X axis as the rotation axis. The maximum radius of rotation K (distance between G′-D) is determined from the trajectory.

Next, the safe turning radius calculating means 10-2
Based on the maximum turning radius K, the maximum radius R of the tool 18 and the offset value V, a safe turning radius S (= K + R + V) at which the workpiece 16 and the tool 18 do not interfere is calculated by the above equation (1).

Next, the safety boundary calculating means 10-3 calculates the turning radius S obtained by the safe turning radius calculating means 10-2.
A cylindrical surface determined by (= K + R + V) is obtained as the safety boundary 19. This safety boundary 19 is stored in the safety boundary area 4e in the database 4.

The turning radius S actually used is the turning radius (S + α) as described above, and the tool 18 is rotated by this α value.
Is kept away from the workpiece 16.

On the other hand, if a material model is not newly created,
The material model selecting means 14 of the three-dimensional CAM 3 proceeds to step # 8, reads out existing material model data from the material model area 4b, and displays it on the monitor.

When a material model similar to the shape of the steam turbine blade, that is, the workpiece 20 shown in FIG. 8 is selected by the operator from the material models displayed on the monitor, the three-dimensional CAM 3 20 is read from the material model area 4b in the database 4.

Next, in step # 9, the safety boundary creating means 10 of the three-dimensional CAM 3 sets an extra value V as an offset value V between the machining model 15 and the workpiece 20 similar to the shape of the machining model 15 by the operation of the operator. Thickness t
Is entered.

Next, the maximum turning radius calculating means 10-1
As shown in FIG. 9, the rotation trajectory of the point D when the workpiece 20 is arranged on the X-axis, that is, the point D when the workpiece 20 is rotated around the X-axis as the rotation axis, is detected. The maximum turning radius K (distance between G′-D) is obtained from the turning trajectory.

Next, the safe turning radius calculating means 10-2
Based on the maximum turning radius K, the maximum radius R of the tool 18 and the offset value V, a safe turning radius S at which the workpiece 20 does not interfere with the tool 18 is calculated and obtained.

Next, the safety boundary calculating means 10-3 calculates the turning radius S obtained by the safe turning radius calculating means 10-2.
Is determined as the safety boundary 19. This safety boundary 19 is stored in the safety boundary area 4e in the database 4.
Is stored.

The rotation radius S actually used is the rotation radius (S + α) as described above, and the tool 18 is rotated by this α value.
Is kept away from the workpiece 16.

Next, the processing origin setting means 13 repeats steps # 12 to # 14, and returns to the processing origin P1 of the tool 18.
It is determined whether or not (0, 0, 300, 0) is set outside the safety boundary 19, and if it is set outside the safety boundary 19, the process proceeds to creation of a machining path. Processing origin P1 (0, 0, 300,
If 0) is not outside the safety boundary 19, the processing origin setting means 1 will continue until the processing origin P1 is set outside the safety boundary 19.
No. 3 outputs an error message “processing origin error”.

Next, the definition of the machining path creation is input to the three-dimensional CAM 3 by the operation of the operator. In step # 15, the three-dimensional CAM 3 defines the processing path creation input by the operator in step # 15, for example, the processing surface, the processing method, the connection method of the processing path, the cutting feed distance before and after the processing, the tool as the data defining the processing path. Approach method,
Tool release method, and furthermore, each NC processing machine 9-1 to 9-n
Is stored in the machining condition area 4d.

Next, in steps # 16 to # 20, the machining path creating means 11 processes the workpiece based on the machining model data created by the three-dimensional CAD 2 and the safety boundary 19 created by the safety boundary creating means 10. Tool 1 for 16
8 to determine the approach operation and the escape operation to create a machining path.

First, creation of a machining path for a newly created material model (workpiece) 16 will be described with reference to FIG.

The following points P1 are used for creating a machining path.
-P6 are defined.

P1: machining origin position (Home) P2: P3 projected on the safety boundary 19 with a tool vector P3: cutting path start position P4: cutting path end position P5: P4 on the safety boundary 19 with a tool vector Projection P6: Projection of the next cutting start position on the safety boundary 19 In step # 16, the machining path creation means 11 uses software to execute the cutting path start position P3 on the safety boundary 19 in the software.
Then, the four axes of the NC processing machine 9-1 are moved.

The movement of the tool 18 from the processing origin position P1 to P2 is the first movement of the processing path, and moves at a predetermined rapid traverse speed. Also in this movement, the interference between the tool 18 and the safety boundary surface is considered. The coordinate values displaced for the movement of the tool 18 are (X, Y, Z, A) and P1
And P2 are: P1 (X = 0, Y = 0, Z = 300, A = 0) P2 (X = P2x, Y = P2y, Z = P2z, A = P2
a)

Next, in step # 17, the machining path creating means 11 sets the cutting path start point P3 on the software.
Lower the tool 18 until.

Tool 1 from point P2 to cutting path start point P3
The tool 8 is moved at a predetermined rapid traverse speed called a moving speed to lower the tool 18.

At this time, the coordinate value displaced for the movement of the tool 18 is Z, and the coordinate values of P2 and P3 are P2 (X = P2x, Y = P2y, Z = P2z, A = P2
a) P3 (X = P2x, Y = P2y, Z = P3z, A = P2
a)

Next, in step # 18, the machining path creating means 11 moves the tool 18 from the cutting path start position P3 to the cutting path end position P4 on the software to perform cutting on the workpiece 16.

In the cutting of the workpiece 16, the tool 18 is moved from the cutting pass start position P3 to the cutting pass end position P4 at a predetermined cutting feed speed called a moving speed. This moving path depends on the definition of the machining path.

The coordinate values displaced for the movement of the tool 18 at this time are (X, Y, Z, A), and P3 and P4
Are coordinate values of P3 (X = P2x, Y = P2y, Z = P3z, A = P2
a) P4 (X = P4x, Y = P4y, Z = P4z, A = P4
a)

Next, in step # 19, the machining path creating means 11 moves the tool 18 from the cutting path end position P4 to a point P5 outside the safety boundary 19 on software.

The movement of the tool 18 from the cutting path end position P4 to the point P5 is performed by moving the tool 18 at a predetermined rapid traverse speed.
Raise 8 outside safety boundary 19.

At this time, the coordinate value displaced for the movement of the tool 18 is Z, and the coordinate values of P4 and P5 are P4 (X = P4x, Y = P4y, Z = P4z, A = P4
a) P5 (X = P4x, Y = P4y, Z = P5z, A = P4
a)

Next, when there is the next cutting, the machining path creating means 11 moves the tool 18 from the point P5 to the next cutting start position P6 at a predetermined rapid traverse speed on the software.

The coordinate values displaced for the movement of the tool 18 at this time are (X, Y, Z, A), and P5 and P6
Are coordinate values of P5 (X = P4x, Y = P4y, Z = P5z, A = P4
a) P6 (X = P6x, Y = P6y, Z = P5z, A = P6
a)

Again, the machining path creating means 11 returns to step # 16, and moves the tool 18 from the point P2 on the software to the cutting path start position P3 on the safety boundary 19 on the software.
Move the four axes of -1.

As described above, the machining path creating means 11 creates steps by repeating steps # 16 to # 19.
When the creation of the machining path is completed, the process proceeds to step # 20, where the tool 18 is returned to the machining origin position P1 at the rapid traverse speed.

The coordinate values displaced for the movement of the tool 18 at this time are (X, Y, Z, A), and P5 and P1
Are coordinate values of P5 (X = P4x, Y = P4y, Z = P5z, A = P4
a) P1 (X = 0, Y = 0, Z = 300, A = 0).

Next, the three-dimensional CAM 3 stores the created machining path in the machining path area 4f in the database 4.

Next, the host processor 6 executes the three-dimensional CA
Machining path area 4f created in M3 and in database 4
, An NC program for performing NC control of the NC processing machine 9-1 is created based on the machining path, and stored in the NC program database 5.

Next, the NC program server 7 receives the NC program stored in the NC program database 5, and sends the NC program to the NC processing machine 9-1.
The program is converted into an NC program corresponding to the data and transmitted to the NC processing machine 9-1 through the data transfer system 8-1.

Thus, the NC processing machine 9-1 moves the tool 18 in accordance with the NC program and cuts the workpiece 16 to create steam turbine blades.

On the other hand, creation of a machining path for the existing material model (workpiece) 20 shown in FIGS. 8 and 9 is the same as creation of a machining path for the newly created material model (workpiece) 20 described above. Yes, and the description is omitted.

When the work 16 is cut by the NC machine 9-1, the shape of the work 16 or 20 is gradually reduced by the cutting.

Accordingly, the safety boundary changing means 12 is operated, the turning radius S is reduced by following the turning radius K of the workpiece 16 or 20 which becomes smaller in accordance with the cutting operation, and the safety boundary 19 is changed. May be changed.

As described above, according to the first embodiment, the work piece 1 or the work piece 16 or 20 at the time of working is processed.
Workpiece 16 based on a maximum turning radius K of 6 or 20
Alternatively, a safety boundary 19 where the tool 18 does not interfere with the tool 20 is created, and an approach operation and an escape operation of the tool 18 with respect to the workpiece 16 or 20 are determined based on the machining model data and the safety boundary 19 to create a machining path. Therefore, the interference of the tool 18 with the workpiece 16 or 20 can be avoided in the operation of the tool 18 entering the machining start point, and the collision of the moving tool 18 with the rotating workpiece 16 or 20 can be prevented. It is possible to create a machining path that can be safely cut using the 4-axis NC machine 9-1, and automatically creates the respective NC programs of the various NC machines 9-1 to 9-n from this machining path. it can.

Therefore, if the NC program database 6 storing the program for creating such a machining path and the program for conversion to the NC program is installed, the tool 18
A CAD / CAM system that creates a machining path capable of avoiding interference of the tool 18 in the approaching and escaping operations can be realized, and by connecting various NC processing machines 9-1 to 9-n to the CAD / CAM system, An NC that can perform NC processing while avoiding interference of the tool 18 in the approaching or retreating operation of the tool 18
A processing system can be realized.

(2) Next, a second embodiment of the present invention will be described.

In the second embodiment, the safety boundary creating means 10 in the first embodiment is modified. As shown in the functional block diagram of FIG. It has each function of the boundary calculation means 10-5.

[0108] Of these, the turning radius calculating means 10-4, as shown in FIG. 11, is used to rotate each of the workpieces 16 or 20 in the direction of the rotation axis A when the workpiece 16 or 20 is rotated. It has a function of obtaining the turning radius Ra.

The safety boundary calculating means 10-5 has a function of directly obtaining each safety boundary surface 22 in each section 21 of the workpiece 16 or 20 from each turning radius Ra obtained by the turning radius calculating means 10-4. Have.

In this case, the NC program database 5
In this case, the rotational radii Ra of the section 16 of the workpiece 16 or 20 in the direction of the rotation axis A when the workpiece 16 or 20 is rotated are determined, and the workpiece 16 or 20 is calculated from the rotational radii Ra. Safety boundaries 22 at each section 21
Is stored.

Even if such a means for creating the safety boundary surface 22 is provided, the tool 18 enters the work 16 or 20 in the operation of entering the tool 18 into the machining start point, as in the first embodiment. Can avoid the collision of the moving tool 18 with the rotating workpiece 16 or 20, and can safely perform the machining path using the 4-axis NC machine 9-1. The NC programs of the various NC machines 9-1 to 9-n can be automatically created from this machining path.

Therefore, if the NC program database 6 storing the program for creating such a machining path and the program for conversion to the NC program is installed, the tool 18
A CAD / CAM system that creates a machining path capable of avoiding interference of the tool 18 in the approaching and escaping operations can be realized, and by connecting various NC processing machines 9-1 to 9-n to the CAD / CAM system, An NC that can perform NC processing while avoiding interference of the tool 18 in the approaching or retreating operation of the tool 18
A processing system can be realized.

(3) Next, a third embodiment of the present invention will be described.

In the third embodiment, the safety boundary creating means 10 in the first embodiment is modified, and as shown in the functional block diagram of FIG. It has the functions of the boundary operation means 10-7 and the safety boundary surface operation means 10-8.

Of these, the radius of gyration calculation means 10-6, as shown in FIG. 11, converts each of the cross-sections 21 of the workpiece 16 or 20 in the direction of the rotation axis A when the workpiece 16 or 20 is rotated. It has a function of obtaining the turning radius Ra.

The safety boundary calculation means 10-7 has a function of calculating each safety boundary in each section 21 of the workpiece 16 or 20 from each rotation radius Ra obtained by the rotation radius calculation means 10-6. .

The safety boundary surface calculation means 10-8 has a function of obtaining a safety boundary surface including the workpiece 16 or 20 from each safety boundary obtained by the safety boundary calculation means 20-7.

In this case, the NC program database 5
In this case, the rotational radii Ra of the section 16 of the workpiece 16 or 20 in the direction of the rotation axis A when the workpiece 16 or 20 is rotated are determined, and the workpiece 16 or 20 is calculated from the rotational radii Ra. A program for obtaining each safety boundary in each cross section 21 is stored.

It is needless to say that the same effect as in the first embodiment can be obtained even if such a means for creating a safety boundary surface is provided.

The present invention is not limited to the first to third embodiments, but may be modified as follows.

For example, if N is equal to or greater than four-axis control including the rotation axis A,
When creating a C program, a safety boundary is created for a material model (workpiece) 16 to be newly created, a machining path is created, and the NC machine 9-is created according to the NC program created based on this machining path. A process of processing the workpiece 16 according to 1-9-n is applied to a rough machining process, and a safety boundary is referred to an existing material model (workpiece) 20 with reference to a thickness of a surplus generated in the rough machining process. Is created to create a machining path, and the NC created based on this machining path
The steps of processing the workpiece 20 by the NC processing machines 9-1 to 9-n according to the program can be appropriately combined, for example, applied to the medium processing step and the finishing processing step.

When the projection 23 is formed at the center of the workpiece 23 as shown in FIG. 13, the workpiece 16 or 20 is rotated as in the third embodiment. The rotational radius Ra at each section 21 of the workpiece 16 or 20 in the direction of the rotation axis A at that time is determined, and the safety boundary surface 22 at each section 21 of the workpiece 16 or 20 is determined from the rotational radius Ra. In this way, during the movement of the tool 18, the collision between the safety boundary and the tool 18, the holder, and the main spindle of the NC processing machine is avoided, and the tool 18 enters and escapes.
N that avoids interference with the material model during machining
C programs can be created.

[0123]

As described above in detail, according to the present invention, it is possible to provide a machining path creating method capable of avoiding interference of a tool in a tool entry or a release operation.

Further, according to the present invention, it is possible to provide an NC program automatic creation method capable of avoiding interference of a tool in a tool entry or escape operation.

Further, according to the present invention, a CA for creating a machining path capable of avoiding interference of a tool in a tool entry or escape operation.
A D / CAM system can be provided.

Further, according to the present invention, it is possible to provide an NC machining system capable of performing the NC machining while avoiding the interference of the tool in the approach and the escape operations of the tool.

Further, according to the present invention, there is provided a storage medium for storing a program for creating a machining path or an NC program created from the machining path, which can avoid interference of the tool in the approaching and escaping operations of the tool. it can.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of an NC processing system to which a three-dimensional CAD / CAM system according to the present invention is applied.

FIG. 2 shows three-dimensional CAD / C in the NC processing system.
FIG. 2 is a schematic diagram showing each area in a database of the AM system.

FIG. 3 is a functional block diagram of a three-dimensional CAM in the NC processing system.

FIG. 4 is a schematic diagram showing a processing model of a steam turbine blade and a newly created material model in the NC processing system.

FIG. 5 is a view showing a processing path creation order when a newly created material model is used in the NC processing system.

FIG. 6 is a flowchart of a machining path creation procedure in the NC machining system.

FIG. 7 is a flowchart of a machining path creation procedure in the NC machining system.

FIG. 8 is a schematic diagram showing a processing model of a steam turbine blade and an existing material model in the NC processing system.

FIG. 9 is a view showing a processing path creation order when an existing material model is used in the NC processing system.

FIG. 10 is a functional block diagram of a safety boundary creating unit according to a second embodiment of the NC machining system to which the three-dimensional CAD / CAM system according to the present invention is applied.

FIG. 11 is a schematic diagram showing an operation of creating a safety boundary in the NC processing system.

FIG. 12 is a functional block diagram of a safety boundary creating unit according to a third embodiment of the NC machining system to which the three-dimensional CAD / CAM system according to the present invention is applied.

FIG. 13 is a view for explaining a modification of the three-dimensional CAD / CAM system according to the present invention.

[Explanation of symbols]

 1: three-dimensional CAD / CAM system, 2: three-dimensional CAD, 3: three-dimensional CAM, 4: database, 4a: machining model area, 4b material model area, 4c: tool information area, 4d: machining condition area, 4e: Safety boundary area, 4f: machining path area, 4g: control program area, 5: NC program database, 6: host processor, 7: NC program server, 8-1 to 8-n: data transfer system (DNC), 9- 1-9-n: NC processing machine, 10: safety boundary creation means, 10-1: maximum turning radius calculation means, 10-2: safe rotation radius calculation means, 10-3: safety boundary calculation means, 10-4: Turning radius calculation means, 10-5: safety boundary calculation means, 10-6: rotation radius calculation means, 10-7: safety boundary calculation means, 10-8: safety boundary surface calculation means, 1 1: machining path creation means, 12: safety boundary changing means, 13: machining origin setting means, 14: material model selection means, 15: machining model, 16, 20: material model (workpiece), 17: moving space, 18: Tool, 19: Safety boundary.

Claims (19)

[Claims] 1. A machining path creating method for creating a machining path of a tool in an NC machine for machining a workpiece with reference to three-dimensional model data, wherein the machining is performed at the time of machining the workpiece. A step of obtaining a safety boundary where the workpiece and the tool do not interfere with each other based on a range required for movement of the object; and a step of creating the processing path based on the three-dimensional model data and the safety boundary. A method for creating a machining path, comprising: 2. A step of obtaining a maximum rotation radius that is an outermost rotation locus position of the workpiece when the workpiece is rotated; and determining the maximum rotation radius based on the maximum rotation radius and the radius of the tool. The machining according to claim 1, further comprising: a step of obtaining a safe rotation radius where the workpiece and the tool do not interfere with each other; and a step of obtaining a cylindrical surface determined by the safe rotation radius as the safety boundary. Path creation method. 3. A step of obtaining each radius of gyration at each section of the workpiece in the direction of a rotation axis when the workpiece is rotated, and each safety at each section of the workpiece from these radii. 2. The method according to claim 1, further comprising the step of obtaining a boundary. 4. A step of obtaining each radius of gyration at each section of the workpiece in the direction of a rotation axis when the workpiece is rotated, and each safety at each section of the workpiece from these radii. The method according to claim 1, further comprising: determining a boundary; and determining a safety boundary surface including the workpiece from the safety boundary. 5. The method according to claim 1, further comprising the step of changing a position of the safety boundary by following a radius of rotation when the workpiece is rotated, which is reduced by processing the workpiece. The processing path creation method described. 6. The method according to claim 1, further comprising the step of: determining whether a machining origin of the tool is set outside the safety boundary, and shifting to creating the machining path. . 7. A step of determining, based on the three-dimensional model data, whether to select a material model having a shape approximate to the three-dimensional model or to select a material model having a predetermined shape. The method according to claim 1, wherein the safety boundary is created for the processed workpiece. 8. The machining path creation method according to claim 1, further comprising a step of creating an NC program for controlling the NC machine based on the machining path. NC program automatic creation method. 9. A CAD / CAD for creating a tool machining path in an NC machine for machining a workpiece by a CAM according to three-dimensional model data created in the CAD.
In the CAM system, a safety boundary creating unit that creates a safety boundary where the workpiece and the tool do not interfere with each other based on a moving space of the workpiece during processing of the workpiece, the three-dimensional model data, Machining path creating means for creating the machining path by determining the approach operation and the escape operation of the tool with respect to the workpiece based on the safety boundary,
A CAD / CAM system comprising: 10. A maximum turning radius calculating means for obtaining a maximum turning radius which is an outermost rotation locus position of the workpiece when rotating the workpiece, the safety boundary creating means, A safe turning radius calculating means for obtaining a safe turning radius without interference between the workpiece and the tool based on the turning radius and the radius of the tool; and a cylindrical surface determined by the turning radius obtained by the safe turning radius calculating means. 10. A CA according to claim 9, further comprising: a safety boundary calculating means for determining a safety boundary as the safety boundary.
D / CAM system. 11. A turning radius calculating means for obtaining each turning radius at each cross section of the work in a direction of a rotation axis when the work is rotated, wherein the turning radius calculation means comprises: 10. The CAD / CAM system according to claim 9, further comprising: safety boundary calculation means for obtaining each safety boundary in each cross section of the workpiece from each rotation radius obtained by the means. 12. A turning radius calculating means for calculating each turning radius at each cross section of the work in a direction of a rotation axis when the work is rotated, the turning radius calculating means, Means for calculating each safety boundary in each cross section of the workpiece from each radius of rotation obtained by the means; and a safety boundary including the workpiece from each safety boundary obtained by the safety boundary calculation means. 10. The CAD / CAM system according to claim 9, further comprising: safety boundary surface calculating means for obtaining a surface. 13. A safety boundary changing means for changing a position of the safety boundary in accordance with a radius of rotation when rotating the workpiece, which is reduced by processing the workpiece. The CAD / claim according to claim 9,
CAM system. 14. A machining origin setting means for judging whether the machining origin of the tool is set outside the safety boundary, and moving to creation of the machining path if the machining origin is set outside the safety boundary. CAD / according to claim 9, characterized in that:
CAM system. 15. A material model selecting means for judging whether to select a material model having a shape similar to the three-dimensional model or to select a material model having a predetermined shape based on the three-dimensional model data. The CAD / CAM system according to claim 9, wherein: 16. An NC that creates an NC program for performing NC control of the NC processing machine based on the machining path.
10. The program according to claim 9, further comprising program creation means.
16. The CAD / CAM system according to any one of claims 15 to 15. 17. A machining path for machining a workpiece by a CAM according to three-dimensional model data created in CAD, and an NC machining system including an NC program based on the machining path. A safety boundary where the workpiece and the tool do not interfere with each other is created based on the movement space of the workpiece during the machining, and an NC program based on the machining path created based on the safety boundary is provided. An NC processing system, characterized in that: 18. A storage medium storing a program for the machining path creation method according to claim 1. Description: 19. A storage medium storing a program of the method for automatically creating an NC program according to claim 8.