JPH06119029A - Method for creating approach route and retract route in NC processing - Google Patents

Abstract

(57) [Abstract] [Purpose] When creating NC data when contouring a work material with a tool having a cutting edge on the side surface, the work site of the work material, the shape of the work material in the vicinity, the amount of cutting etc. Automatically create an optimal approach (retract) route that takes into consideration. [Structure] Priorities are set in advance for approach (retract) route patterns, and for the approach (retract) route point sequence with a constant Z value created for each pattern, evaluation points for predetermined evaluation elements are obtained, and the evaluation is performed. It is determined which of the predetermined determination zones the point belongs to, and when the evaluation point belongs to the non-adoptable zone of the determination zone, an approach (retract) route for changing the Z value is created and the evaluation point is calculated. To do. If there is a route with an evaluation point that belongs to the adoptable zone of the judgment zone, determine the approach (retract) route to be adopted according to the priority,
When there is only an approach (retract) route having an evaluation point belonging to the warning zone of the determination zone, the route to be adopted is determined according to the size of the distance between the work and the tool.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to NC in NC processing.
Regarding the method of creating data, especially when contouring a work material (workpiece) with a tool having a cutting edge on the side (flat end mill), etc., use the tool as the cutting start point of the work without the tool interfering with the work. The present invention relates to a method for automatically creating a so-called approach path and retract path, in which a tool is released from a cutting end point of a workpiece.

[0002]

2. Description of the Related Art Generally, when cutting a work (work) with an NC device, recently, using a CAD system or the like, data concerning a working shape of a work to be cut, a tool used for cutting, etc. An NC data creation system has been used in which the data is input, path data of the tool is automatically created based on these data, and NC data is created.

When performing contour processing (profile processing) of a work material (workpiece) by an NC device using a machining center, the tool cuts into the cutting start point of the work piece as NC data without the tool interfering with the work piece. In addition, the so-called approach route and retract route that allow the tool to escape from the cutting end point of the workpiece are NC as described above.
It becomes necessary to create it as tool locus data by the data creation system.

Generally, a tool path (tool locus) to a first cutting start point of a work draws a smooth locus such as an arc or a curve according to a machining allowance (cutting allowance) of a work to be machined. However, a cutting approach method in which the tool is gradually cut into the work is preferable in terms of processing conditions. The retract route is similar.

In Japanese Patent Laid-Open No. 64-32310, as a method for creating an approach path, the approach height and length are obtained from the workpiece machining allowance and the tool diameter, and the approach length data is read from the cutting path data. The maximum value of the Z value in the coordinate system is obtained from that, and the linear distances from the cutting start point to many cutting points in the cutting path data are obtained, and the Z value increment is calculated based on the approach height and length described above. Calculate and add Z value increment of each cutting point
The maximum value is added to obtain the Z coordinate value of the approach point, and the coordinates having the X and Y coordinate values and the Z coordinate value at each cutting point following the cutting start point before the cutting start point of the cutting path data. A creation method is disclosed in which data is added in the reverse direction from the cutting start point.

[0006]

The method of creating an approach path described in the above-mentioned prior art uses the ball end mill having a cutting edge at the tip thereof to create an approach path when approaching a shaped surface from above the work. It is related to the method, and is an effective means when cutting a shaped surface with a ball end mill, but contour processing of a workpiece using a flat end mill having a cutting edge on the side surface (profile processing for cutting the external shape) However, the present situation is that the operator is manually operating the NC device while cutting the NC device.

That is, when the contouring of a work is performed by using a flat end mill, the machining shape, the machining mode and the tool to be used are different, and the machining shape is particularly remarkable in the cutting of a press die of an automobile. Due to the complexity, if interference can occur between the work and the tool,
During the cutting process in the NC device, the worker performs the spot facing process in advance to ensure the safety of the operation area of the tool, then approaches the cutting start point of the workpiece from the vertical direction and finishes the cutting. The operation of retracting the tool from the work was performed vertically from the point.

For this reason, the operator manually approaches the NC device to perform approach and retract operations while considering the interference of the tool depending on the work site and the shape of the work in the vicinity thereof. Especially, a flat end mill is used. In the case of contouring used, there is no cutting edge at the tip of the tool,
Since it has a cutting edge on the side, approach from the side of the tool,
A large number of factors depend on the operator, such as the need for retract operation and the need for the operator to monitor until the end of cutting, and as a result, a major factor that hinders unattended machining by automatic operation of the NC device. It was.

Therefore, the present invention has been made to solve the above-mentioned inconvenience, and NC data of NC data in the case of contour-cutting a work (work) with a tool (flat end mill) having a cutting edge on the side surface is provided. At the time of creation, an optimum approach route and retract route that automatically consider the machining area (form) of the workpiece and the shape of the workpiece in the vicinity and the amount of cutting allowance (finishing allowance) An object of the present invention is to provide a retract route creating method to prevent interference between a work and a tool, and to enable unmanned machining operation during cutting in an NC device.

[0010]

In order to achieve the above-mentioned object, the present invention provides an NC machining for contouring a work material with a tool having a cutting edge on a side surface thereof, in which the tool is cut between the tool and the work material. Of the approach path and the retract path, the approach path having a constant Z value, which is the vertical position of the tool based on the machining conditions, for each of a plurality of approach path and retract path types having a predetermined priority. A step of creating a point sequence and a retract route point sequence, and an evaluation point for a predetermined evaluation element is calculated for the created approach route point sequence and retract route point sequence, and the evaluation point is a predetermined determination zone. Which of the evaluation zones of the constant Z value constant approach path point sequence and retract path point sequence are determined in the determination zone. When belonging to the impossible zone, a step of changing the Z value to create an approach route and a retract route, and calculating the evaluation point is included, among the evaluation points of the approach route point sequence and the retract route point sequence of each type. When there is an approach route and a retract route having an evaluation point belonging to the adoptable zone of the determination zone, an approach route and a retract route to be adopted for processing are determined according to a predetermined determination criterion, and the warning zone of the determination zone is set. If there are only approach and retract routes that have an evaluation point to which they belong,
It is characterized in that the approach route and the retract route adopted for the processing are determined according to a predetermined criterion.

Further, according to the present invention, when there are a plurality of approach routes and retract routes having evaluation points belonging to the adoptable zone of the determination zone, the approach route and the retract route having the highest priority and the determination zone of the determination zone are set. If there are only multiple approach and retract routes that have evaluation points belonging to the warning zone, select the approach route and retract route with the longest distance between the work material and the tool as the approach route and retract route to be used for machining. Is characterized by.

[0012]

According to the method for creating the approach route and retract route in NC machining according to the present invention, in the NC device for contouring a work material with a tool having a cutting edge on the side surface, an approach route between the tool and the work material In creating the retract route, in advance, in order of the preferred approach route and retract route type, for example, the arc type route has the first priority, the linear type route has the second priority, and the reverse arc type route has the second priority. It is set as the third priority, and each type of approach route and retract route is created and evaluated.

As the evaluation method, the approach, the distance between the retract point and the work, whether the approach and the retract point affect the stock removal of the work, the amount of movement of the tool in the Z-axis direction (vertical direction) (Z coordinate). value)
Whether the approach route and retract route can be created with a certain amount, whether the approach route and retract route are such that the workpiece is cut before reaching the cutting start point or after the cutting end point, etc. are set in advance. Which type of approach is selected from the approach route and the retract route, which are calculated depending on whether the evaluation point is obtained and which of the three judgment zones that are set in advance, that is, the adoptable zone, the warning zone, and the non-adoptable zone, are evaluated. It is made to decide whether to adopt the route and the retract route.

When the above-mentioned evaluation points calculated for the approach route point sequence and the retract route point sequence calculated for each type are in the applicable zone, the approach route and the retract route to be adopted are determined in the order of the preset priority. However, when in the warning zone, the approach path and retract path having the maximum distance between the approach and retract points and the workpiece to be machined are selected and determined.

For this reason, in the NC data creation system, based on the input processing conditions, first, for each approach route and retract route pattern having a preset priority, an approach route point sequence with a constant Z value and A retract route point sequence is created, and an evaluation point for the evaluation element predetermined as described above is calculated for the created approach route point sequence and retract route point sequence.

It is determined which of the predetermined determination zones the evaluation points of the approach route and the retract route of each pattern belong to, and the evaluation points of the approach route point sequence and the retract route point sequence having the constant Z value are the above-mentioned. When it belongs to the non-adoptable zone of the determination zone, the approach route and the retract route for changing the Z value are created, and the evaluation points are calculated in the same manner as described above.

Next, if there are a plurality of approach routes and retract routes having evaluation points belonging to the applicable zone of the judgment zone among the evaluation points of the approach route point sequences and retract route point sequences of each type, According to a predetermined criterion, that is, a predetermined high priority order, the approach route and the retract route to be adopted for processing are determined, and only the approach route and the retract route having the evaluation points belonging to the warning zone of the determination zone are set. When there are a plurality of them, the approach route and the retract route adopted for machining are determined according to a predetermined criterion, that is, the magnitude of the distance between the tool and the work.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The approach route and retract route creating method in NC processing according to the present invention will be described below in detail with reference to the accompanying drawings. When performing contour processing (profile processing) of a work material (workpiece) with an NC device that uses a machining center, NC
As data, it is necessary to create so-called approach route and retract route data in which the tool is cut into the cutting start point of the work without interfering with the work and the tool is released from the cutting end point of the work.

In particular, when a flat end mill having a cutting edge on the side surface of the tool is used for cutting, since the cutting edge is not provided, the work piece is cut from the side surface of the tool to cut the workpiece from the side surface of the tool. It is necessary to take an approach route and a retract route that leave. In addition, the tool path (tool path) to the first cutting start point of the work gradually draws a tool while drawing a smooth path such as an arc or curve according to the machining allowance (cutting allowance) amount of the workpiece. The cutting approach method of cutting the workpiece into the work is preferable in terms of processing conditions. The retract route is similar.

FIG. 1 is a diagram showing types of approach paths and retract paths when cutting is performed using a flat end mill. In FIG. 1, a point P on the work W is a cutting start point, and S is a machining allowance. For this work W, arcuate path A ₁ as the tool T ₁
The approach type from the approach point Q ₁ to the cutting start point P with the cutting edge on the side of the tool and cutting in the direction of arrow A is called the arc type, and along the straight path A ₂ like the tool T _2. A type of approaching from the approach point Q ₂ to the cutting start point P and changing the advancing direction of the tool to the A direction at the cutting start point P is called a straight line type, and like the tool T ₃ , the cutting direction (arrow A) is A type of approaching from the approach point Q ₃ to the cutting start point P on the arcuate path A ₃ in the reverse direction and changing the advancing direction of the tool to the A direction at the cutting start point P to perform cutting will be referred to as a reverse arc type.

Similarly for the retract route, depending on the cutting progress direction of the tool and the escape direction from the work, like the tool T ₄ ,
An arc type that leaves the work W along the arc-shaped path A ₄ from the cutting end point E and reaches the retract point Q ₄ .
Like the tool T ₅ , the direction is changed to the cutting direction A at the cutting end point E, and the work W is separated from the work W along the straight path A ₅ , and reaches the retract point Q ₅ , and the cutting end point is set like the tool T _6. There is a reverse arc type in which the direction is changed to the cutting direction A by E, the work W is separated from the work W by a reverse arc-shaped path A ₆ , and the retract point Q ₆ is reached.

Here, arc type (T ₁ and T _{4 in} FIG. 1)
The approach route and the retract route can be smoothly machined in the tangential direction from the cutting start point P or the cutting end point E, and can be smoothly connected to the tool locus. On the other hand, in the straight type (T ₂ and T _{5 in} FIG. 1) approach paths and retract paths, since the traveling direction of the tool T changes at the cutting start point P or the cutting end point E, the M / C is temporarily changed. There is a risk that the load on the side will change, chattering of the tool on the machining surface and M / C stoppage will occur, and that a cutter mark will be attached.

Similarly, the reverse arc type (T ₃ in FIG. 1,
The approach route and the retract route of T ₆ ) have the same problems as those of the straight-line type approach route and the retract route, and in addition to the upper cut (the rotation direction of the tool and the traveling direction of the tool are opposite to each other) up to the cutting start point P. Since the cutting will be in a relation of direction), compared to arc type etc.,
There is a problem that the cutting load on the tool becomes large.

Therefore, according to the present invention, when creating the approach route and the retract route, the arc type route has the priority 1, the straight type route has the priority 2, and the reverse arc type route has the priority 3. An approach route and a retract route are created, evaluated by the evaluation method described below, a high priority type approach route and a retract route are adopted, and approach route and retract route data are created.

In the NC data creation system, approach path and retract path data, which are the main NC data, and tool path data, are processing conditions such as data related to work material and shape, data related to shape to be processed, and data related to tool to be used. Gives data, checks the interference between the work and the tool, etc., without approaching the work, the tool approaches the predetermined cutting start point, cuts to the cutting end point, and then retracts the tool from the cutting end point. It is created by calculating the tool path.

FIG. 2 is a view showing the relationship between the shape of the work W to be cut and the tool T. The tool T, the holder part for holding the tool T, the drive shaft, and the like are the work W in the cutting process.
It is necessary to create a tool path without contacting the unnecessary part. This is called interference avoidance (interference check),
As shown in the figure, interference checks such as quill interference avoidance A, holder interference avoidance B, shank interference avoidance C, tool side interference avoidance D, tool bottom (tip) interference avoidance E, etc. are performed, and the tool trajectory, approach path, and retract are performed. Route data is calculated.

Whether or not the calculated approach path and retract path can be used for cutting the work depends on the distance between the approach, the retract point and the work,
Whether the approach and retract points are applied to the work removal allowance, whether the approach path and retract path can be created with a constant Z-axis direction (vertical direction) movement amount (Z coordinate value) of the tool, or before the cutting start point is reached Alternatively, it is decided by evaluating factors such as whether or not the approach route and the retract route are such that the workpiece is cut after the cutting end point.

In the present invention, with respect to the evaluation points for each of these evaluation elements, the smaller the degree of the obstacle when the calculated approach route and retract route are adopted for cutting the workpiece to be machined, the smaller the evaluation, and the larger the obstacle, the larger the evaluation. In addition, the evaluation element has a smaller weighting for each evaluation element, which has a smaller influence degree when the evaluation element is used for cutting the target work, and has a larger weighting for an evaluation element having a larger influence degree. It is preset as a kind of evaluation function.

Then, using the evaluation points set as described above, the approach route point sequence and the retract route point sequence calculated for each of the above-mentioned evaluation elements for each of the arc type, the straight line type, and the reverse arc type. Of the approach route and retract route calculated depending on which of the three judgment zones that are set in advance, that is, the adoptable zone, the warning zone, and the non-admissible zone. Decide whether to adopt the type of approach and retract routes.

Here, in the present invention, when the evaluation points calculated for the approach route point sequence and the retract route point sequence calculated for each type are in the adoptable zone,
The approach route and retract route to be used for cutting the workpiece to be machined are determined in the order of preset priority (arc type = priority 1, straight line type = priority 2, reverse arc type = priority 3), and the warning zone , The approach path and retract path having the maximum distance between the approach and retract points and the workpiece to be machined are selected and determined.

FIG. 3 is a diagram showing an example of the relationship between the tool and the work when determining the approach route and the retract route as described above. 3 (a) is a case of cutting at the die S takes the workpiece W to the illustrated shape, the tool T ₁
Arc type shown in, Tool T ₂ straight type, Tool T
_The approach paths calculated for each of the reverse arc types shown in ₃ are shown.

In the arc type approach path of the tool T ₁ , the approach point Q ₁ is in contact with the work W and causes interference, and the evaluation point is in the non-applicable zone, and the straight path approach path of the tool T ₂ is used. Is a state in which the machining allowance S is outside the cutting section of the work before the approach point Q ₂ reaches the cutting start point P, and the evaluation point is the warning zone. In the inverse circular arc type approach path of the tool T ₃ , the work W and the approach point Q ₃ are sufficiently separated from each other, and there is no problem in the path to the cutting start point P, and the evaluation point enters the adoption zone. The reverse arc type approach path has the lowest priority, but there is no other approach path of the evaluation point that enters the adopted zone. Therefore, in this example, the reverse arc type approach path by the tool T ₃ is adopted.

FIG. 3 (b) shows approach paths calculated respectively for the arc type shown in the tool T ₁ and the straight line type shown in the tool T ₂ when the work W is cut in the illustrated shape with the stock removal S. . Similarly to the above, the evaluation point of the arc type approach path of the tool T ₁ is in the warning zone, and the evaluation point of the linear type approach path of the tool T ₂ is in the adoption zone. In this case as well, the linear type approach route has a lower priority than the circular arc type approach route, but since it is in the adoption zone, the linear type approach route by the tool T ₂ is adopted.

Similarly in FIG. 3 (c), when the work W is cut into the shape shown in the drawing with the machining allowance S, the arc type shown in the tool T ₁ , the straight type shown in the tool T ₂ , and the reverse shown in the tool T _3. The approach paths calculated for each arc type are shown. In this case, any type of approach route
Work point W at approach points Q ₁ to Q ₃
It depends on the machining allowance S on the facing surface side, and the evaluation points are all in the warning zone. In this case, of the distances a, b, and c between the approach points Q ₁ to Q ₃ and the work W,
A linear type approach path with the tool T ₂ having the maximum distance b is adopted.

Similarly, FIG. 3 (d) shows a work shape as shown.
When cutting the W with the stock removal S, the tool T₁Shown in
Circular arc type, tool T₂Linear type, tool T shown in₃To
The approach route calculated for each of the reverse arc types shown
Shows. In this case, the tool T₁Arc type appro
Only approach route Q₁At the work
It depends on the machining allowance S on the opposite side of W, and the evaluation point is a warning
Enter Zone, Tool T ₂Straight type, tool T₃Reverse circle of
There is no problem with the arc type approach route, and evaluation points are adopted
Enter the zone and have a high priority tool T₂Straight line type
The approach route of is adopted.

FIG. 4 is a diagram showing a configuration of an NC data creating system for creating an approach route and a retract route according to the present invention. This NC data creation system has a central processing unit and is used in a computer 2 having a role of graphic calculation, display control, database management, etc., a magnetic disk database 4 capable of storing and updating a large amount of graphic information, and created in the system. An NC data output device 6 for outputting NC data, a display device 8 which is a central device for dialogue between the system and its user and is used in conjunction with an input device, a tablet 10 connected to the display device 8, Keyboard 12, mouse 14,
It is composed of an input device such as a volume switch 16.

The NC data creating system has many programs as shown in the logical configuration diagram of FIG. Each program can be classified into the following modules according to the function to be shared. Operating system 32 and control module 34 for controlling processing and information flow in the NC data creation system, various input devices, for example, input module 44 for assisting smooth input operation corresponding to keyboard 12, input An input interpreting module 40 for interpreting the displayed information according to a command command format, a display module 38 for managing display information and a display process according to the command, and a graphic process according to the command including a sub-module corresponding to the command. Figure processing command module 24 to perform, database operation module 50 for efficiently searching and accumulating a large amount of information necessary for the NC data creation system held in database 54, macro program 28a which is an automatic design program
A macro module 28 for executing the above, an external system interface 30 for exchanging information with another CAD system or an NC data creation system, and an interlocking process, and the like.

Further, in order to maintain the expandability and maintainability of the system, a system control file 22 for storing the system configuration and standard values, a command control file 42 for storing the operability of each command and the program control procedure, An auxiliary file such as a display control file 36 for storing the model and configuration of the display device is prepared.

Also, a graphic processing library 46 for processing graphics, a display library 48 for displaying on the display device 8, and NC data created by the system are NC.
An NC data conversion utility 56 for outputting to the data output device 6 and a data exchange utility 52 for coupling with another system are prepared.

Next, each module will be briefly described. The control module 34 standardizes the centralized management of control in the system and the calling procedure by modularizing the program group and interposing between the modules. Its functions include start, end, abnormal processing, execution control of each module, execution history recording, debug function, and special processing with the operating system 32.

The input module 44 provides the user with a comfortable input procedure according to the specification in which various input methods of various input devices are unified. The function is to prompt the user for the type of information to be input, the input method and the input device, select the input information, and convert the input information into the standard type.

The input interpretation module 40 unifies the method of interpreting the input information and the result display to support various input instruction methods to improve the input operability and maintain the expandability of the system. Its function is to interpret the input information and display the interpretation result.

The display module 38 uniformly processes various display operation requests and manages display information and display state. The function manages the display device, display control, display information management, and display state management.

The graphic processing command module 24 centrally manages the format of the input argument, the calling of the processing program according to the command, and the processing method of the result, and maintains the maintainability and expandability of the system.

The database operation module 50 standardizes the request method from other modules and provides a recovery means when a failure occurs. The functions are management of database usage, operation of the database 54, processing at the time of failure, and the like.

The external system interface 30 standardizes the exchange of information with other systems to make effective use of the NC data creation system. The function exchanges information with an external system and controls the operation of an external program.

The macro module 28 controls the execution of the NC data creating system according to the created macro program 28a. Its function is macro program 28
Translation and execution of a.

The tool locus calculation module 26 is based on the inputted working conditions, that is, the work material data and the shape data, the shape data to be machined, the working condition data such as the data of the tool to be used, and the like. , Retract route data etc. are calculated.

6 and 7 are flow charts showing the procedure for creating the approach route and retract route according to the present invention. The NC data creation system (see FIGS. 4 and 5) is required to create tool path data, approach, and retract path data from the input device such as the keyboard 12 before creating approach and retract path data. As the processing conditions, data regarding the work material and shape, data regarding the shape to be processed, data regarding the tool to be used, etc. are input. The input processing condition data is interpreted by the input interpreting module 40 and sent to the tool trajectory calculating module 26 via the input module 44 and the control module 34.

In the tool locus calculation module 26, first, the type n of the approach route and the retract route is set to 1 in step S1. n is a numerical value of the priority described above, 1 is an arc type, 2 is a straight line type, and 3 is a reverse arc type. In each of the following steps, the approach route and retract route of the type designated by this numerical value are calculated, the evaluation points of the approach route and the retract route are calculated, and which of the determination zones this evaluation point falls in is calculated, The type n is changed to 2 and 3, the approach route and the retract route of each type are calculated, and the same processing is repeated.

In step S2, the approach path point sequence of the specified type (initially an arc type with n = 1) with a constant Z value (vertical direction of the tool, the coordinate value of the Z axis is constant), or retract. A path point sequence is calculated, interference check in the Z-axis direction and interference flag setting are performed (step S3), then two-dimensional interference check and interference portion deletion are performed (step S4). This interference check is N
It is possible to use a method of interference check which is generally performed in C data generation.

Next, in step S5, the tool trajectory calculation module 26 calculates the evaluation points of the approach route point sequence or the retract route point sequence calculated in step S2, and evaluates which one of the determination zones is to be entered. Is done. For example, the adoptable zone is set to m _n = n + 10, the warning zone is set to m _n = n + 20, and the adoptable zone is set to m _n = _n.
= N) (step S6), the evaluation points of the approach route or the retract route in which the Z value (Z-axis coordinate) changes are calculated in step S7. For example, the adoptable zone is m _n = n + 30, and the warning zone is m _n = n + 4.
0, the non-adoptable zone is m _n = 50, which of the determination zones is evaluated, and the process proceeds to step S8.

On the other hand, in step S6, if the evaluation point is in the adoptable zone or the warning zone, the process proceeds to step S8. If the approach / retract route pattern is not 3 or more, n is incremented by 1 (step S
9) Then, the processes of steps S2 to S9 are repeated to evaluate the approach route point sequence and the retract route point sequence of the arc type (n = 1), the straight line type (n = 2), and the reverse arc type (n = 3). Are sequentially performed.

As described above, when the evaluation points of the approach route point sequence and the retract route point sequence of each pattern and the evaluation zone to which the evaluation point falls are completed, the work is cut. The approach route and retract route to be adopted are determined in step S of FIG.
It is determined by the procedure after 10. That is, step S1
When the evaluation point m _n is less than 20 at 0 and the evaluation point is less than 40 at step S13,
The approach or retract route having the evaluation point is in the adoptable zone, and the approach route and the retract route having the minimum evaluation point m _n are adopted in step S11. This means that when there is a route pattern in which the evaluation points of the respective evaluation elements are the same, the approach route and the retract route having a pattern with a small n, that is, a pattern with a small priority are adopted.

In step S12, the evaluation point m _n is 30.
When the evaluation point m _n is less than 50 in step S14, the approach route or retract route having the evaluation point is in the warning zone, and in step S15, the approach route and retract route point sequence are The approach route and retract route with the longest distance to the work are adopted.

In step S14, the evaluation point m _n is 5
When it is 0 or more, all of the calculated approach route and retract route are in the non-adoptable zone, and they do not hold as a tool locus. Therefore, it is necessary to change the machining section for cutting or change the machining planning. In step S16, an error message to that effect is displayed on the display device 8 (see FIGS. 4 and 5), and the process ends.

As described above, when the approach and retract route data are created and evaluated by the tool locus calculation module 26, and the approach and retract route data to be adopted are determined, these approaches and retract route data are , Is output from the tool trajectory calculation module 26 together with the tool trajectory data, is stored in the database 54 under the control of the database operation module 50, and is converted into NC data by the NC data conversion utility 56 during machining in the NC device. , NC
It is output to the data output device 6 and used for NC processing.

[0058]

According to the approach route and retract route creating method in NC processing according to the present invention, the following effects can be obtained. That is, the present invention, in the approach path and retract path creating method, uses a tool (flat end mill) having a cutting edge on the side surface to work material.
When NC data is created for contour machining, the optimum approach route and retract route are automatically created, taking into consideration the machining area (form) of the workpiece, the workpiece shape in the vicinity of it, and the cutting allowance (finishing allowance). It is possible to prevent the interference between the work and the tool, and it becomes possible to perform an unmanned machining operation at the time of cutting in the NC device.

[Brief description of drawings]

FIG. 1 is a diagram illustrating types of approach routes and retract routes according to the present invention.

FIG. 2 is a diagram showing a relationship between a work and a tool interference check.

FIG. 3 is a diagram showing a relationship between a tool and a work when determining an approach path and a retract path.

FIG. 4 is a configuration diagram of an NC data creation system that creates approach and retract route data according to the present invention.

FIG. 5 is a logical configuration diagram showing a logical configuration of an NC data creation system.

FIG. 6 is a flowchart showing an approach route and retract route generation procedure according to the present invention.

FIG. 7 is a flowchart showing an approach route and retract route generation procedure according to the present invention.

[Explanation of symbols]

 2 ... Computer 4 ... Magnetic disk database 6 ... NC data output device 8 ... Display device 10 ... Tablet 12 ... Keyboard 14 ... Mouse 16 ... Volume switch 26 ... Tool locus calculation module 40 ... Input interpretation module 44 ... Input module 50 ... Database operation Module 54 ... Database 56 ... NC data conversion utility

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naohino Watanabe 1-10-1 Shin-Sayama, Sayama-shi, Saitama Honda Engineering Co., Ltd.

Claims (3)

[Claims] 1. A method for creating an approach route and a retract route between a tool and a work material in NC machining for contouring a work material with a tool having a cutting edge on a side surface, the method being predetermined. Creating a series of approach path points and retract path point rows having a constant Z value, which is the vertical position of the tool, based on the machining conditions, for each of a plurality of approach path and retract path types having priority, For the approach route point sequence and the retract route point sequence, a step of calculating an evaluation point for a predetermined evaluation element and determining which of the predetermined determination zones the evaluation point belongs to, the Z value constant approach When the evaluation points of the route point sequence and the retract route point sequence belong to the non-adoptable zone of the determination zone, the Z value is changed to approach. Comprising a step of creating a route and a retract route, and calculating the evaluation point, among the evaluation points of the approach route point sequence and retract route point sequence of each type, the evaluation points belonging to the adoptable zone of the determination zone When there are approach routes and retract routes, the approach routes and retract routes to be adopted for processing are determined according to a predetermined criterion, and only the approach routes and retract routes having the evaluation points belonging to the warning zone of the determination zone exist. In this case, the approach route and the retract route in the NC process are characterized in that the approach route and the retract route adopted for the process are determined according to a predetermined criterion. 2. The approach route and retract route creation method according to claim 1, wherein when there are a plurality of approach routes and retract routes having evaluation points belonging to the adoptable zone of the judgment zone, the approach with the highest priority is given. A method for creating an approach route and a retract route in NC processing, characterized in that a route and a retract route are selected as an approach route and a retract route adopted for processing. 3. The approach route and retract route creating method according to claim 1, wherein only a plurality of approach routes and retract routes having evaluation points belonging to the warning zone of the determination zone are present, the distance between the work material and the tool. A method for creating an approach route and a retract route in NC processing, characterized in that the longest approach route and retract route are selected as the approach route and the retract route to be adopted for processing.