JPH10340115A - Hollow recognition method for turning nc data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically recognize the hollows of a turning machining product and to decide a tool that is suitable to the hollow machining. SOLUTION: The finishing shape of a turning machining product is successively defined as segments AB, BC, CD... at a single end A of the finishing shape and traced for each of branch points B, C, D... at and after an intersection point A. If the machining product moves in its axial direction and also in the direction (minus direction of axis Z) opposite to the axial direction, the section set between both directions is decided as an end face hollow. If the machining product moves in the direction perpendicular to its axial line (axis X) and also in the direction opposite to the vertical direction, the section set between both directions is decided as the radial direction hollow. In such a way, the hollows are recognized for the turning NC data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for automatically generating turning NC data. More specifically, the present invention relates to a method for recognizing a dip in turning NC data, which is capable of automatically determining and recognizing a dimple in a machining area and a finished shape from an arbitrary material shape.

[0002]

2. Description of the Related Art In NC machine tools, the path of a tool is commanded by a program. This path is manually programmed. This manual programming, that is, one in which a person calculates and programs a tool path, requires a lot of programming work. In recent years, in order to reduce the number of program steps, an automatic programming apparatus has been used which inputs data interactively using a CRT screen and creates NC data from a design drawing by a simple operation. Various methods for automatically creating NC data for turning have been proposed and implemented. For example, JP-A-61-103213
In the official gazette, material shape data classified in advance,
An NC data creation method capable of automatically determining a necessary processing step order and a processing area from finish shape data is described.

[0003]

According to the above-described NC data creating method, a machining area is automatically determined. In the case of a relatively simple shape such as a round bar or a perforated round bar, the determination of the processing area is relatively simple. However, when a material having an arbitrary shape such as a forged product is used, there are portions to be cut and portions not to be cut. For efficient cutting without empty cutting,
The area to be cut and the area not to be cut must be accurately identified.

[0004] In many cases, the finished shape of the turned product has a groove or a concave portion, that is, a depression on the outer peripheral surface, the inner peripheral surface of the inner hole, the end surface, or the like. The conventional NC data creation method does not accurately classify and recognize the shape of the depression. For this reason, there has been a problem that the most suitable tool for the concave machining cannot be selected, and the machining efficiency is reduced, and the machining method cannot be automatically determined. The present invention has been made in view of these problems, and achieves the following objects.

An object of the present invention is to provide a method for automatically determining a machining area of NC data for automatically determining a cutting area in turning of an arbitrary material shape.

Still another object of the present invention is to provide a method for automatically recognizing a dimple in a turned NC data for automatically recognizing a dimple in a turned product.

Still another object of the present invention is to provide a turning N for determining a tool suitable for forming a recess in a turning operation.
An object of the present invention is to provide a method for recognizing a depression of C data.

[0008]

To solve the above-mentioned problems, the present invention takes the following means. The first means traces the finished shape from one end of the finished shape of the workpiece to be turned at each branch point, and when the movement of the finished shape in the axial direction and the movement in the opposite direction to this movement occur, this area is faced. When it is determined as a depression, when movement in the direction perpendicular to the axial direction of the finished shape and movement in the direction opposite to this movement occur, this region is determined as a radial depression, and the entrance point and exit of the recognized depression are recognized. Define a point, select a single-edged tool to cut the recognized dent, define a straight line that defines an angle that can be machined from the shape of the single-edged tool that cuts the dent from the branch point at the entrance, and select This is a method of recognizing the turning NC data for recognizing the hollow by dividing the hollow into two parts on the straight line so that the hollow is turned by the single-edged tool.

[0009] In the first means, a portion which is left uncut after cutting with the selected single-edged tool is automatically selected as a tool opposite to the selected single-edged tool.
This is a method for recognizing depressions of C data.

[0010]

According to the present invention, the finish shape is traced from one end of the finish shape of the work to be turned at each branch point, and when the movement direction of the work to be turned in the axial direction and the movement in the direction opposite to this movement direction occur, this section is determined. This method is a method of recognizing a dip in the turned NC data in which a section is determined to be a radial dip when it is determined to be a dip in the end face and a movement in a direction opposite to a direction perpendicular to the axis of the finished shape occurs.

[0011]

DETAILED DESCRIPTION OF THE INVENTION those shown in NC data creation apparatus Figure 1 is a block diagram showing an example of the NC data creating apparatus of the present invention. Central processing unit (hereinafter C
The PU 1) controls and controls the entire NC data generating apparatus. A graphic display device 3 and an input device 4 including a keyboard device are connected to the CPU 1 via a bus 2. The processing information memory 5 is a RAM memory, and stores information related to processing of a work material such as a material of the work material, a material shape, a finished shape, and a processing step order. The control program memory 6 is a ROM, and stores necessary programs such as a control program of the data creating apparatus, a program for determining a machining area described later, and a program for finding a hollow. The NC data output device 7 outputs the created NC data to a paper tape,
Output means for outputting to an external storage medium such as a bubble cassette or an IC card. The cutting area memory 8 is a RAM memory that stores the position and shape of the cutting area determined according to a method described later.

The depression memory 9 is a RAM for storing the position and shape of the depression similarly determined according to a method described later.
Memory. The creation data memory 10 is a RAM memory that temporarily stores input data, processing results, created NC data, and the like.

Principle of Working Area Determination Method The solid line shown in FIG. 2 is a half sectional view showing an example of a finished shape at the time of turning. Hereinafter, the principle of the present invention will be described with reference to the embodiment shown in FIG. The figure shown by the dashed line indicates the shape of the material, and the solid line is the contour line indicating the finish shape to be machined by cutting this material. The finished shape and the material shape are stored in the processing information memory 5. The storage of the material shape and the finished shape is performed as follows. Line segments A′L are named as material line segments 1 and line segments LD ′ are named as material line segments 2.

This definition is defined by a straight-line equation at the X and Z coordinates, and a start point and an end point of the straight-line equation. Similarly, for the finishing shape, the line segment AB is the finishing line segment 1, the line segment BC is the finishing line segment 2,.
And sequentially define the line segments and name them. The Z axis is the same as the center line of the lathe main axis, and the X axis points in the radial direction. First, when it is considered that the starting point of the finished shape, the corner, that is, the point A as a starting point, moves on the line to the point K, a line segment in the positive direction of the X-axis direction, that is, a line segment in the positive direction parallel to the X-axis line is used as a boundary. In the example of FIG.
(Hereinafter referred to as “vertical elements”). The cutting area is determined in the following order from the vertical component I. Starting point A
Starting from the point, a search is made as to whether there is an intersection where a line segment in the minus direction of the X-axis (hereinafter, referred to as a first direction) intersects the contour line of the material shape. In the example shown in the figure, there is no intersection in the first direction, so the camera is rotated 90 degrees in the counterclockwise direction, and the intersection is similarly searched for in the plus direction of the Z axis (hereinafter, referred to as the second direction). In the second direction, an intersection A 'is found. In other words, it intersects with the starting point A 'of the line segment 1 of the material shape. At this point, the search for the intersection from the point A side is stopped. The stop of the search from the point A side is performed in the third direction, ie, 1
Repeat until an intersection is found up to 80 degrees.

Next, a search for an intersection is started from the end point B of the vertical element I, that is, the end point B of the finished shape in the vertical element I. Starting from the point B, an intersection with the contour line of the material shape is first searched for in the plus direction (first direction) of the X-axis. As a result, in the example shown in the figure, the line intersects the line segment 2 of the material shape at the intersection B '. Search starting from point B is usually 9
The line segment is extended in units of 0 degrees, and a search is made up to 180 degrees in the vertical element I. When an intersection from the start point A and the end point B of the element I is found, a cutting area is determined next.

First, the finishing line segment 1 from the finishing shape point A to the point B, the line segment BB ', the line segment B'L in the material line segment 2 of the material shape, and the line segment LA' which is the material line segment 1 , And a region surrounded by the line segment A'A so as to sequentially rotate clockwise. After all, the cutting region is a region surrounded by the contour line of the finish shape and the contour line of the material shape, that is, rectangular A, B, B ', L,
A '.

The direction in which the tool is moved, in other words, the cutting direction, is determined by the ratio of the line segment AB '/ AA' whether to cut in the X-axis direction or in the Z-axis direction. Thus, the processing region and the cutting direction in the first step are determined. In the case of element II, it is determined as follows. As in the case of element I, B
Search for an intersection in the negative X-axis direction starting from the point. However, since there is no intersection, it is further rotated 90 degrees in the counterclockwise direction to search, but there is no intersection in the area of the element II. Further turn 90 degrees counterclockwise to find the intersection.

Thus, the intersection with the contour line of the material shape intersects at the intersection B '. Since the finishing shape is offset by the finishing allowance, in the area to be actually cut, the remaining portion offset by the finishing allowance to the finishing shape is roughly cut. Next, an intersection is searched for from the end point E of the element II. However, since it is defined in advance that there is no need to cut between the finish shape segments ED in the input machining process, the intersection is searched for from the point D. At the point D, a contour line of the material shape is searched in the plus direction of the X axis.

However, since the finishing shape is offset by the finishing allowance, the intersection of the material shape and the contour cannot be found. Next, the intersection starting from point C is the first
They cross each other in the direction X-axis direction, that is, the point C '. In this manner, the cutting area becomes substantially ΔBCC'B 'of the area surrounded by the finished shape and the material shape. The cutting direction is the ratio of the X-axis and Z-axis length directions, that is, the line segment BB '/ B'
Determined by the ratio of C '.

The factor III is determined as follows. The section of the line segment EF is a section that does not need to be cut off according to the input definition, and an intersection starting from the point E cannot be found. The intersection cannot be found because point F has no cutting allowance. At point F, Z
Although there is an intersection with the contour line in the axial direction, the intersection is not an intersection here because it is a space and not integral with the intersection. Similarly,
I can't find point G either. Starting from point H,
The intersection point H 'can be obtained in the Z-axis direction.

Next, starting from the end point I of the element III, the intersection is searched for according to the above-mentioned rule. As a result, an intersection point I 'is obtained. Eventually, the rectangular areas H, I, I ', M, and H', which are areas surrounded by the finished shape and the material shape, are the cutting regions. The finishing margin is provided between the line segment IH and the line segment HH '. Hereinafter, elements IV and below are determined in the same manner as described above. Since the material is searched for by the above-described method, if there is a dent W in the material shape as shown in FIG. 3A, the dent cannot be recognized and it is assumed that there is no dent W.
The cutting area is determined and handled as shown in FIG.

[0022]NC data creation order of cutting area Figure 4 actually creates NC data according to the above method
The following shows the flow of processing. First, whether the work is of an arbitrary material shape
Judgment, if the shape is arbitrary, finish shape in advance
Read from the file of the processing information memory 5 stored and held
See in. Determine whether the read finish shape is a vertical element
If it is not a vertical element, read the next finished shape,
If the element is a fresh element, finish reading (step
P₁, P_Two, P _Three). Note that in step 1
If it is determined that the workpiece is not a shape,
Move to the shape (round, perforated) program.

A finishing margin is given to the read finished shape (P ₄ ). Loaded finish shape is determined whether the outer diameter, if not the outer diameter, moves to the inside diameter for machining area determination program (P _5). The method for determining the intersection of the outer diameter machining area determination program is the same for the inner diameter machining area determination program, and a description thereof will be omitted. A straight line in the X-axis direction is defined from the start side according to the method described above (P ₆ ). In the example of FIG. 2, a straight line is defined from point A.

The first line segment 1 of the material side shape in the vertical element I, for example, the line segment A'L which is the material line segment 1 in the example of FIG.
Is read to determine the intersection (P ₇ , P ₈ ). If there is no intersection, the next line segment of the material-side shape, that is, the line segment LD 'which is the material line segment 2 in the example of FIG. 2, is read and repeated until an intersection is found. If the intersection is not found even when all the line segments of the vertical element of the material are read, the next straight line rotated by 90 degrees is defined. The intersection is sequentially searched for on this straight line as described above.

If the intersection does not exist, the process moves to the next starting point according to the above-described principle, and the intersection is similarly obtained. If an intersection is found on the start side, a straight line in the first direction is defined from the end point side of the element I (P ₉ ). A line segment of the material shape is read from the end of the element I, and an intersection is searched for in the same manner as described above (P ₁₀ ). It is determined whether there is an intersection between this line segment and the straight line in the first direction (P ₁₁ ). If the intersection cannot be found, the next straight line next to the end point of the material shape is read to search for the intersection. If there is no intersection even when all the line segments of the vertical element I are read, the next straight line rotated clockwise is defined, and the intersection with the material shape is searched for as described above.

After these steps, the cutting area is determined and the cutting area is stored (P ₁₂ ). Next, as described above, the aspect ratio of the cutting area is obtained (P ₁₃ ), and according to this ratio, the X-axis direction, X
Or axially, to determine whether to process send tool in either direction (P _14). When the above operation is completed, the data is output to the creation data memory 10 (P ₁₅ ). When the above operation is completed, data of a shape excluding the part where the processing region is determined from the material shape is created (P ₁₆ ). After the creation of this data, to register the newly created material shape to the material shape file (P _17). Performed until the shape finishing this work is the last (P _18).

The recess recognition method Next, the shape with a recess in the finish shape (hereinafter, referred to as recesses) cutting tool in the case of, describes examples of determining a cutting region. FIG. 5 is an example showing a sectional view of a workpiece. In this example, there are recesses I to VIII, and the outer peripheral surface, the inner peripheral surface, the end surface, and a mixture thereof. The recess I is formed on the end face at the back of the inner diameter. Hollow II
Is formed on the inner peripheral surface of the inner diameter. The depression III has depressions IV, V and VI on the front end face of the outer diameter, and depressions VII and VIII on the rear end face of the outer diameter. The depression VI and the depression VII are located at the boundary between the end surface and the outer peripheral surface.

The finish shape is sequentially defined as line segments AB, BC, CD,..., And the line segments are named and input. First, starting from the point A of intersection with the center line (Z-axis line) in the inner diameter, tracing is performed along the contour line toward the intersection I of the front end face of the inner diameter and the outer diameter. Starting from the point A, the line segment AB to the point B becomes a straight line parallel to the X-axis, and does not change in the Z-axis direction. A line segment BC from point B to point C is in the minus direction of the Z axis.
When a minus in the Z-axis direction occurs, a flag is set.
The line segment CD is parallel to the X-axis and does not fluctuate in the Z-axis direction. The line segment DE is a plus direction only in the Z-axis direction. If an amount equal to or greater than the line segment BC occurs in the direction opposite to the line segment BC, the flag is defeated.

After all, when focusing only on the fluctuation in the Z-axis direction,
If the minus length of the line segment BC and the plus length of the line segment DE alternately have the same length (absolute value), the area surrounded by the rectangle BCDD 'is determined to be a hollow. The line segment DD 'is a line segment having the same length (absolute value) as the line segment BC. This depression is named depression I, and its shape and position are registered in the depression memory 9. If there is a depression at the center (centered on the Z axis), then a plus appears first, and then a minus appears. In this case, the first is determined to be a depression.

Since there is no depression in the Z-axis direction between the line segments E...
In this section, it is determined that there is no dent at the end face. Next, a hollow in the radial direction (X-axis direction) of the inner diameter is searched for.
The radial direction of the inner diameter, that is, the depression on the inner peripheral surface is searched for from the point I toward the point A. The line segment IH is parallel to the Z axis and does not change in the X axis direction. The line segment HG is a plus direction in the X-axis direction. Here, a flag is set in the memory. The line segment GF is parallel to the Z axis and does not change in the X axis direction. The line segment FE is a minus direction in the X-axis direction. When a minus occurs, the flag in the memory is defeated.

In this manner, when the rectangle appears in the X-axis direction in the order of plus and minus, the rectangle surrounded by the line segment HGFE is determined to be a depression, and this region is stored as a depression II. In the section I... A, it is determined that the depression II is present in the inner circumferential direction of the inner diameter. In the same manner as described above, a depression in the section from the outermost peripheral point Z to the point I is searched. When minus and plus in the Z-axis direction appear alternately on the same principle as the recess on the inner diameter end face, the section is determined to be a recess on the end face. Eventually, seek out hollows III, VII, and VIII on the end face.

Next, a depression on the outer peripheral surface in the section from the point I to the point Z is searched for. Focusing on the change of the plus and minus signs in the X-axis direction based on the same principle as above, the depression IV is recognized first, and then the depression V is recognized. This recognition is performed as follows. First, a flag is set because the line segment KL has a minus direction in the X-axis direction. The line segment LM is parallel to the Z axis and X
There is no axial change. Since the line segment MN has a positive direction in the X-axis direction, it is recognized as a depression only by the depth of the line segment MN. But,
Since the size of the line segment MN is smaller than the size of the line segment KL, the region of the depression IV is not determined at this stage.

The line segment NO has no change in the X-axis direction. Since the line segment OP is subtracted again in the X-axis direction without returning by the length of the line segment KL, a second flag different from the above flag is set. Since the line segment PQ does not change and the line segment QR returns in the plus direction, the second flag is turned down, and the depression V is recognized based on the same principle as described above. After the indentation V is recognized, the line segment ST is returned in the plus direction, so that the entire indentation IV is recognized for the first time. Next, the depression VI is recognized. These are all stored in the indentation memory 9 with numbers.

When the recess on the end face and the recess on the outer peripheral face overlap, it is defined as an outer recess and recognized as follows (FIG. 6).
Is an enlarged view). The line segment WX at the exit of the outer peripheral recess VI is in the region of the recess VII on the end face. In the depression VI, a line segment VW of the depression VII on the end face is inserted between the entrance line UV and the exit line WX. That is, it is determined whether or not there is a line segment number of the exit line segment WV of the depression VII between the line segment number of the entrance line segment UV and the exit line segment WX of the depression VI. In this way, the overlapping recesses of the recesses VI and VII are defined as outer-side recesses, and are processed.

The recess of the cutting area determination method Figure 7 is a schematic diagram showing the outline of the cutting area determine the recess outer diameter when cut with a single-edged bytes. A line segment is defined at an angle α from the point K at the entrance of the depression IV, and an intersection K ′ with the line segment LM is obtained to divide the region into two regions a and b. This angle α is a sub-cutting angle of the tool as shown in the figure. Similarly, one of the depressions V is bisected into a region c and a region d. The cutting area by the tool having the sub cutting angle α becomes the area a + c, and this area is cut first. For the remaining cutting areas b and d, a tool in the opposite direction to the tool is automatically selected and cut. The recess in the end face of the inner diameter is cut in a similar manner by dividing the cutting area.

The outer end recesses extending over both are directly finished without such division. This is because depressions that span both are often relatively small depressions.

[0037] depression flow of search Figure 8 is a flow diagram of the operation to search for a recess. The outer diameter and the inner diameter are distinguished by the finished shape (P ₁ ) In accordance with the method described above, reading is started from the data storing the line segment from the end point of the inner diameter, that is, the intersection of the center line and the contour line of the inner diameter. In the example of FIG. 5, the process starts from the line segment AB (P
_2, P _3). Find I depression end face of the inner diameter from the input value (P _4). Next, at the starting point of the inner diameter, that is, in the example of FIG.
In the section starting from point I to point A, search for a radial depression II on the inner peripheral surface.

Both the inner surface and the inner surface of the inner diameter are closed.
Look for anything lost (P ₇) Inside this hollow
Defined as an edge depression. In addition, inside each hollow
Search for hollows (P₉). When these are finished, the inner diameter relationship
Each of the depressions is registered in the depression memory 9.
(P_Ten). As for the outer diameter cavity, search for the cavity as above and register
Yes (P₁₁). Insert a tool to cut the inner diameter
The tool file stored in the machining information memory 5
(P₁₂). However, it was processed with the tool
In this case, if the above-mentioned uncut part occurs,
Decide one reverse tool to cut the minute (P₁₃, P₁₄).

The tools necessary for machining the inner diameter end face, outer diameter, outer diameter end face, etc. are determined in the same manner as the inner diameter portion. When these depressions are determined, a cutting area is determined for each depression according to the method described with reference to FIG. 7 (P ₁₆ ). After this determination, it is stored in the NC data file (P ₁₇ ).

[0040]

As described in detail above, since the cutting area is divided into vertical elements based on the finished shape, an area with less empty cutting can be determined. Since the cutting direction is determined based on the shape of the cutting area, efficient cutting can be performed. In addition, by classifying the depression, a tool, a cutting area, and a cutting method that match the depression can be determined.

[Brief description of the drawings]

FIG. 1 is a functional block diagram illustrating an outline of an NC data creating apparatus.

FIG. 2 is a diagram showing an example of a finished shape and a shape of a material at the time of turning.

FIGS. 3A and 3B are diagrams showing recognition when a material has a shape having a special dent. FIGS.

FIG. 4 is a diagram showing a flow of determining a cutting area of NC data.

FIG. 5 is a cross-sectional view showing an example of a finished shape of a recessed workpiece.

FIG. 6 is a diagram illustrating an example in which a depression on an end face and a depression on an outer periphery overlap each other.

FIG. 7 is a diagram showing a cut processing area of a depression;

FIG. 8 is a diagram illustrating a flow of an operation of searching for a depression.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... CPU 5 ... Processing information memory 6 ... Control program memory 7 ... NC data creation device 8 ... Cutting area memory 9 ... Recess memory 10 ... Creation data memory

Claims (2)

[Claims] 1. A finish shape is traced from one end of a finish shape of a workpiece to be turned at each branch point, and when the finish shape moves in an axial direction and in a direction opposite to this movement, this area is depressed in an end face. When movement in the direction perpendicular to the axial direction of the finished shape and movement in the opposite direction to this movement occur, this area is determined to be a radial depression, and the entrance point and the exit point of the recognized depression. Defining a single-edged tool for shaving the recognized dent, defining a straight line defining an angle that can be machined from the shape of the single-edged tool for machining the dent from the branch point of the entrance, Turning NC for recognizing the hollow by dividing the hollow into two parts so as to turn the hollow with a single-edged tool
Data dent recognition method. 2. The concave recognition of cutting NC data according to claim 1, wherein a portion which is left uncut after cutting with said selected one-edge tool is automatically selected and cut in a direction opposite to said selected one-edge tool. Method.