JP3148108B2 - How to check 5-axis NC data - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining the quality of 5-axis NC data for providing a tool path to a machined surface of a workpiece such as a press die to be cut or ground, in other words, a workpiece. The present invention relates to a method of checking 5-axis NC data to be checked by a simulation operation of a tool.

[0002] A tool is a 5-axis numerically controlled machine tool (hereinafter referred to as a
Also called NC machine tool. ), Which is mounted on a 5-axis NC machining center or the like and has cutting edges on the outer periphery and end faces.

[0003]

2. Description of the Related Art As a prior art of this kind, there is a technique disclosed in Japanese Patent Application Laid-Open No. 63-119934 filed by the present applicant. This technique is based on a point group (also referred to as powder) and a tool path (also referred to as a cutter path) generated on a processing shape surface, and calculates the presence or absence of interference between the point group and the tool path by so-called calculation. This is an excellent technique that allows checking the quality of tool path data given as NC data without fail before actually machining a workpiece by checking by simulation.

When the point group interferes with the tool path (in the case of interference), for example, it is determined that a desired cutting state (also referred to simply as cutting) is present, and in the case of non-interference (without interference). In this case, it is determined that the machine is in the uncut state (also simply referred to as uncut part). In this case, a point in a desired cutting state is referred to as a cutting point, and a point in an uncut state is referred to as an uncut point.

The prior art is based on the premise that an NC machine tool has three axes that are orthogonal to each other, and the tool mounted on the spindle head of the three-axis NC machine tool also has a tip with a half end. It has been limited to three-axis NC data as a tool path data of a so-called ball end mill having a circular shape.

However, the external shape of a work such as a press die generally has a free-form surface, and in order to process such a free-form surface shape accurately and efficiently in a short time, a revolving shape is required. It is preferable to perform machining using a 5-axis NC machine tool having three axes orthogonal to the axes (to be described in detail later).

[0007]

Heretofore, there has been no method of checking the quality of cutting by 5-axis NC data provided to the 5-axis NC machine tool by simulation.
For this reason, conventionally, when checking the quality of the cutting by the 5-axis NC data, the so-called test piece is actually tested by a 5-axis NC machine tool that actually operates based on the 5-axis NC data. Had to do.

Therefore, conventionally, there has been a problem that it takes a lot of man-hours (time) to check the quality of the shaving based on the 5-axis NC data, and that expensive test pieces for trial machining must be prepared. .

The present invention has been made in view of such problems, and provides a tool path to a processing shape surface of a work such as a press die to be cut or ground.
It is an object of the present invention to provide a method of checking 5-axis NC data that enables a so-called desk to check the quality of the cutting of the axis NC data by a simulation operation of a tool for a workpiece.

More generally, it is an object of the present invention to provide a general-purpose method for finding uncut portions of a machined surface with respect to 5-axis NC data in which the direction and shape of a tool can be arbitrarily set.

[0011]

SUMMARY OF THE INVENTION The present invention relates to a machined surface having a predetermined pitch with reference to the origin of an XYZ orthogonal three-axis coordinate system.
Was generated point group represented by the data, the tip of the tool
XYZ coordinates and inclination of the tool axis viewed from the YZ plane and X
In a 5-axis NC data check method for checking a cutting state by a tool path represented by 5-axis NC data including an inclination viewed from a Z plane by simulation, a tool attribute is set, and the 5-axis NC data is set based on the 5-axis NC data. Extracting the inclination of the tool and recognizing a local coordinate system based on the position of the tool; converting the data for the point cloud generation into data based on the local coordinate system; and In contrast, when scanning the tool along the path of the tool, interference between the tool and the point cloud
Moving the tool in the tilt direction on the local coordinate system;
Checking the distance between the blade portion of the tool and the point group at the time of cutting to extract uncut points of the point group.

In this case, since the point group generated on the machining shape surface is converted into data of a local coordinate system based on the position of the tool, the 5-axis NC data for providing a tool path and the machining shape surface Calculation at the time of interference check with
The uncut points of the point group on the processed shape surface can be easily extracted.

Also, the present invention is characterized in that, when the tool is a ball end mill, a center position coordinate in which the tip end position of the ball end mill is raised in an axial direction of the ball end mill by a radius is obtained, and the raised center position is obtained. Calculate the distance between the point group generated axially above the coordinates and the axis of the ball end mill, the point group whose distance exceeds the radius of the ball end mill is the uncut point, and the distance is The point group within the radius of the ball end mill is a shaving point, and the distance between the point group generated axially below the raised center position coordinate and the tip position of the raised ball end mill is calculated. The point group whose distance exceeds the radius of the ball end mill is defined as an uncut point, and the point group whose distance is within the radius of the ball end mill is defined as a cutting point. It is characterized in. In this case, the center position coordinates where the tip position of the ball end mill is raised in the axial direction by the radius are considered as the origin, which is the reference of the local coordinate system, and the distance between the axis passing through the origin and the point group is calculated. Points that exceed the radius of the ball end mill are left uncut points,
Further, the distance between the origin and the point group is calculated, and a point group exceeding the radius of the ball end mill is regarded as a remaining cutting point, and a point group within the radius of the ball end mill is recognized as a desired cutting point. Therefore, it is possible to easily extract the uncut portion of the machining by the ball end mill by a simple calculation process.

When the tool is a square end mill, the coordinates of the center of the center of the tip of the square end mill are considered to be the origin which is the reference of the local coordinate system, and a point group generated above this origin in the axial direction and the axis of the square end mill are considered. The point group exceeding the radius of the square end mill is calculated as the uncut point, and the point group within the radius of the square end mill is recognized as the cut point. For this reason, even in the case of a square end mill, uncut points can be easily extracted by simple calculation processing.

When the tool is a radius end mill, the distance between the axis of the radius end mill and the point group is calculated, and the point group whose distance exceeds {(D-2R) / 2} is left, and the distance is calculated. The point group within {(D-2R) / 2} is a cutting point, and the distance between the axis and the point group when the radius end mill is raised in the axial direction by R is calculated.
A point group that is equal to or less than (D / 2) is defined as a shaving point, and a distance between the center position coordinate of the R shape and the point group is calculated. Point groups that did not exist are left as uncut points. Therefore, even in the case of the radius end mill, the uncut portion can be easily extracted by a simple calculation process.

Furthermore, by displaying a point group whose position is designated by the uncut point data on the machined shape surface, the uncut point can be visually and intuitively recognized.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

First, a general configuration of a 5-axis NC machine tool will be described.

FIG. 1 shows a general configuration of a portion including a head 11 of a 5-axis NC machine tool. The head 11
It is mounted on a transfer shaft 12 movably mounted on a 5-axis NC machine tool body. The transport shaft 12 is transported in the X-axis, Y-axis, and Z-axis directions through feed mechanisms by motors (not shown) for XYZ axes, which are three orthogonal axes.

An approximately triangular prism-shaped first rotating member 13 having a predetermined flat inclined surface 13a moves around a C-axis parallel to the Z-axis.
The shaft motor 15 can be turned in the direction of the arrow α. Also, the inclined surface 14 which is in sliding contact with the inclined surface 13a.
a with respect to the C axis, for example, 50 °
Second rotating member 14 having an arm portion 14c extending in a direction inclined by φ, for example, 10 ° with respect to the B axis inclined by 10 °.
However, it can be turned around the B axis by the B axis motor 16 in the direction of the arrow β. The second rotating member 14
Is a flange portion 14b having the inclined surface 14a, and an arm portion 1 integrally manufactured with the flange portion 14b.
4c and a chuck fixing portion 14d fixed to one end of the arm portion 14c.

Chuck fixing portion 1 in second rotating member 14
A chuck 17 is integrally fixed to 4d. At one end of the chuck 17, a rotary processing tool 1 such as an end mill having a diameter D and having a cutting edge on a side peripheral surface and a bottom surface is attached. The tool 1 is driven by a tool motor (not shown) at a high speed in the direction of arrow γ or in the opposite direction, for example, at 10,000 r.
It is configured to be able to rotate at a speed of about pm or more.

Under such a configuration, the tool 1 is transported in the X, Y, and Z directions through the transport shaft 12, and
First rotating member 13 rotated by C-axis motor 15
Is rotated around the C axis, and is rotated around the B axis by the second rotating member 14 rotated by the B axis motor 16. As described above, the 5-axis NC machine tool can be said to be a machine having the XYZ axes, which are three orthogonal axes, and the two axes B and C that rotate.

The tool path data of the 5-axis NC machine tool is based on the XY of the tip 1b (also referred to as the tip center point) of the tool 1.
It is determined by the Z coordinate and the inclination angle of the axis (axis) 1a of the tool 1. In this case, as shown in FIG. 2, the inclination angle A (also referred to as inclination) when the axis 1a of the tool 1 is viewed from the YZ plane, as shown in FIG.
Y and the inclination angle (also referred to as inclination) AX viewed from the XZ plane
And is represented by Note that in FIG.
ax and 1ay indicate the projection of the axis 1a of the tool 1 on the XZ plane and the projection on the YZ plane, respectively.

Therefore, tool path data of the 5-axis NC machine tool (also referred to as 5-axis NC data and tool path data).
Is represented by Nd, the tool path data Nd is Nd = Nd
It is represented by 5-axis NC data of (x, y, z, AX, AY). FIG. 3 shows a configuration of an NC data check system 21 to which the embodiment of the present invention is applied. The NC data check system 21 is composed of a computer, and a control unit 22 that functions as interference (cut or uncut) check means or point cloud data generating means or the like.
have.

The control unit 22 stores, in the form of an end mill, which is a cutting or grinding tool 1 for machining a work such as a press die (not shown), data such as dimensions, types, shapes, etc., that is, tool data representing so-called attributes (parameters). Td and an NC data creation device (CAD
/ CAM device) and tool path data Nd, which is 5-axis NC data, are stored in databases 23, 2 respectively.
Supplied from 4. Further, the control unit 22 is supplied from the database 25 with three-dimensional data representing the shape of the work surface of the workpiece, that is, processed shape surface data Sd which is so-called surface model data or solid model data.

The control unit 22 is a computer, and as is well known, a central processing unit (CPU), an I / O port connected to the central processing unit, a read-only memory (ROM) in which system programs and the like are written. , Random access memory (RAM) for temporarily storing processing data
A read / write memory), an external memory such as a hard disk for storing an application program such as a point cloud data generation program / interference (cut or uncut portion) check program, and a CR as a display means.
A display 31, such as a T, a digitizer tablet 32, a keyboard 33, and a mouse 3, each of which is an input means.
4, a volume switch 35, and a plotter / printer (not shown) as output means are connected.

The control unit 22 stores the scraping check data Cd of the interference check result in the database 26. Each of the databases 23 to 26 is a storage unit such as a hard disk, and it goes without saying that the configuration may be changed to a configuration in which one storage unit is shared.

Next, the operation of the above embodiment will be described first with reference to the overall flow shown in FIG. The control entity is the control unit 22 unless otherwise specified.

The control unit 22 is 5-axis NC data, and stores the trajectory (scanning trajectory) of the tip of the tool 1 and the inclination (AX,
AY) is read from the database 24 as tool path data Nd (Ndj) (step S1).

Next, processing shape surface data Sd (also referred to as a processing target surface) of a work to be processed (cutting or grinding target) is read from the database 25 (step S2).

Next, the tool data Td is read, and parameters (attributes) such as tools are set (selected) while viewing the screen on the display 31 using the keyboard 33 and the mouse 34 (step S3). There are the following five items (1) to (5) for setting parameters of tools and the like.

(1) First, the shape of the tool is shown in FIG.
A ball end mill 1bc having a semicircular tip cutting edge shown in FIG. 5A, a square end mill 1sc used in side cutting, step cutting, groove cutting, etc., in which the outer peripheral blade and the bottom blade shown in FIG. A radius end mill 1rc having an R shape at a corner (corner) shown in FIG. 5C is exemplified.

(2) Next, a tool diameter (diameter) D is selected. In this case, when the tool 1 is the ball end mill 1bc, the radius R of the blade surface is calculated as R = D / 2.

(3) Next, a radius end mill 1
When rc is selected, the radius R of the R shape of the corner (referred to as the bottom R portion br) is selected. When this radius R is selected, a straight line portion (also referred to as a distance) Ds of the blade portion on the bottom surface is:
The distance is given by Ds = (D−2R). As will be described later, the radius end mill 1rc has a straight portion having a diameter D and a straight portion having a diameter (D-2R) and a diameter (D-2R).
-2R) on the circumference of the circle.

(4) A desired pitch of the point group with respect to the processing target surface represented by the processing shape surface data Sd, that is, a desired density and a desired pitch between each point group surface (powder surface) and the processing target surface. Set the distance of The processing target surface is a free-form surface, and the point cloud surface is stretched in parallel with the free-form surface.

(5) Further, the thickness of the surface to be processed is set. Note that the setting of the plate thickness is a setting corresponding to the plate thickness of a pressed product formed by the press dies (upper die and lower die) when the processing target is a press die.

After setting the parameters of the tools and the like in step S3, a point group (powder) having a desired density is given to the machined shape surface read in step S2 (step S4). With this, one or more point group surfaces (powder surfaces) for checking the cutting state (interference state) within a certain distance (constant thickness) above and below the surface of the processing shape surface are formed on the processing shape surface. It is formed in parallel (meaning that the distance between corresponding points between the processing shape surface and the point cloud surface is constant). In this case, each point group surface (powder surface) is provided with points (coordinate points, and, if necessary, points, point data, point data, point group data or powder) at a constant density for easy understanding. Data) is formed.

As shown in FIG. 6, the point P (also referred to as Pi) is a point number i which is an identification number, the coordinates co = co (x, y, z) of the point Pi, and the uncut result ( Status)
Is composed of three data of a flag f representing The case where the value of the flag f is f = 1 is referred to as uncut (including the case of not yet cut), and the case where the value of the flag f is f = 0 is referred to as an interference state or a cut state. In this sense, in order to facilitate understanding of the invention, the value of the flag f is f
In the case of = 1, the flag f = may be left, and in the case of the flag f = 0, the flag f = turned off.

Next, the inclination of the tool 1, that is, the axial direction is calculated (step S5). As described above, since the tool path data Nd is represented by Nd = Nd (x, y, z, AX, AY), the inclination angle AY of the axis 1a of the tool 1 viewed from the YZ plane and the XZ plane It can be easily calculated (extracted) from the observed inclination angle AX (see FIG. 2).

When the XYZ orthogonal coordinate components of the tool path data Nd and the point data Pi are to be distinguished, the tool path data Nd is expressed as Nd = Nd (xn, y
n, zn, AX, AY) and the point data Pi
Is represented by Pi = Pi (xp, yp, zp).

Next, whether or not the tool path specified by the tool path data Nd interferes with each of the point group planes (point groups constituting the point group data) specified by the point group data P is determined for each specific tool 1. The surface is virtually scanned and checked (step S6). In this case, based on the result of the interference check, in other words, the uncut portion check result, the cut check data Cd by the tool is stored in the database 26, and the display indicating the cut state on the processed shape surface is displayed on the display 31. . It should be noted that the shaving check data Cd means uncut and / or cut as required.

Next, regarding the details of the machining interference check in step S6, the tool 1 includes a ball end mill 1bc, a square end mill 1sc, and a radius end mill 1r.
The description will be made separately for each case c.

Prior to the detailed description, the prerequisites for the processing interference check in step S6 will be described before the description can be easily understood.

As shown in FIG. 7, the ball end mill 1b
The tool path data Ndj representing the coordinate point of the tip 1b of c is
For example, as indicated by Nd1, Nd2,..., Ndm, they are given as discontinuous coordinate points (each point is also referred to as an interpolation reference point). The trajectory between adjacent interpolation reference points is given by, for example, linear interpolation, circular interpolation, spline interpolation, etc.
In this embodiment, at each coordinate point of the tool path data Ndj, a machining interference (uncut portion) check in step S6 in FIG. 4 is performed. This tool path data Nd
j and the three-dimensional position (x, y,
z) is given as data based on the origin OG of the XYZ orthogonal three-axis coordinate system. In this sense, a coordinate system based on the origin OG is referred to as a reference coordinate system.

In FIG. 7, points drawn by dots are point data Pi generated on the machined surface Sd.

In the example of FIG. 7, since the ball end mill 1bc is inclined from the Z axis (in some cases, it is parallel to the Z axis), the tip 1b (also referred to as tip center coordinate) has a machined shape. It does not touch the surface Sd. Further, the processed shape surface Sd is a free-form surface.

In this embodiment, when performing the machining interference check, the tip 1b of the ball end mill 1bc is set at each interpolation reference point of the tool path data Ndj.
Is regarded as the origin of the local coordinate system. Therefore, at the origin OG ', the tool path data Ndj = Ndj (xn, yn, zn, AX, A
Y) is tool path data Ndj = Ndj (0,0,0,
AX, AY). In this case, the X 'axis and the Y' axis which are the X axis and the Y axis of the local coordinate system are parallel to the X axis and the Y axis of the reference coordinate system, respectively, and the Z axis of the local coordinate system is the reference coordinate system. Is a Z 'axis inclined in the direction of the axis 1a from the Z axis.

The point data Pi is converted into data based on the local coordinate system. That is, the point data Pi defined from the origin OG of the reference coordinate system is expressed as Pi = P
i (xp, yp, zp), which is point data Pi = Pi defined from the origin OG ′ of the local coordinate system.
(Xp-xn, yp-yn, zp-zn).

In the machining interference check, the tool path data Nd and the point data Pi are converted into data in the local coordinate system, and then the cutting edge portion of the ball end mill 1bc (the tip end portion and the outer circumference in the ball end mill 1bc) The point position where interference between the (point) and the point position specified by the point data Pi has occurred is referred to as a cutting point (cutting point) position, and the point position where no interference has occurred is an uncut point (uncut point). Process as a position. This process may be performed for each tool path data Ndj for all points of the tool path data Nd and all points of the point data Pi. That is, for example, the number of point data Pi (also referred to as a parameter).
When i is i = 1 to n and the number of interpolation reference points (also referred to as a parameter) of the tool path data Ndj is j = 1 to m, first, the interpolation reference represented by the tool path data Nd1 At the point, machining interference check with all the point data Pi is performed. After the machining interference check is completed, at the interpolation reference point represented by the next tool path data Nd2,
A process of performing a machining interference check with all remaining point data Pi not having interference (cutting point) may be continued up to the last machining point represented by the tool path data Ndm.

In the following description, the tool path data Ndj is also referred to as an interpolation reference point Ndj in order to avoid complexity and facilitate intuitive understanding.

The interference check processing of the square end mill 1sc and the radius end mill 1rc is basically the same as the processing interference check processing of the ball end mill 1bc.

The above is the premise of the processing interference check in step S6, particularly the conversion to the local coordinate system.

Next, the details of the machining interference check (remaining machining check) in step S6 will be described for the case where the tool 1 is a ball end mill 1bc.

FIG. 8 shows that the tool 1 is a ball end mill 1bc.
9 shows a detailed flowchart of the remaining machining check in step S6 in the case of.

First, it is assumed that the flags f of all the points Pi generated on the machining shape surface Sd are left at f = (step S11). By this processing, all points Pi are recognized as uncut points.

Next, the parameter j is set to j = 1 (step S12), the first coordinate point of the tool path data Nd1 is recognized, and the coordinate point is set as the origin of the local coordinate system (step S13).

Next, the coordinates of all the points Pi for which the flag f = remains are converted to a local coordinate system having the tool path data Nd1 as the origin (step S14).

Next, assuming that the parameter i is i = 1, the point Pi considers an interference check for Pi = P1 (step S15).

Therefore, the point P1 is the tool path data N
If the point is located on the minus side in the Z′-axis direction from the tool tip coordinate represented by d1, the flag f of the point P1 is left at f = (step S16). In this process, as shown in FIG. 9A, the ball end mill 1bc
The reference line 43 (Z ′) passing through the interpolation reference point Ndj at the tip 1b of
If the point P1 is located on the minus side on the Z 'axis from the axis, that is, orthogonal to the tool axis 1a), the point P1
It is assumed that the flag f of f is left. In the figure, a point Pi indicated by a dot is set to the flag f by the processing in step S15.
Is the point at which f is left.

In FIG. 9A, the upper side is a shaved portion 41 and the lower side is a non-shaded portion 42 based on the processed shape surface Sd. As can be seen from FIG. 9A, in this example:
The tip 1b of the ball end mill 1bc is not in contact with the machined surface Sd, but the side 1c of the tip R is in contact with the machined surface Sd.

Next, the ball end mill 1bc is set to a radius R
The center point coordinates (also referred to as center position coordinates) Ncj (see FIGS. 9A and 9B) of the ball end mill 1bc raised in the plus direction of the Z ′ axis by (D / 2) are obtained (step S17).

Here, the reference line 4 passing through the center point coordinates Ncj
4 (see FIG. 9B), the distance Li between the point Pi present on the plus side in the Z′-axis direction and the axis 1a of the ball end mill 1bc, that is, the Z′-axis is calculated. And L
The flag f of the point Pi where i> R (the radius of the ball end mill 1bc) is f = remaining, and the flag f of the point Pi where Li ≦ R is f = turn off (step S1).
8). By the processing in step S18, the portion shown by hatching in FIG. 9B is cut off in the simulation. In the figure, the dot drawn on the plus side of the reference line 44 is the point Pi where the flag f is set to f = remain.
Is represented.

Further, as shown in FIG. 9C, the distance PLi between the point Pi located on the minus side in the Z'-axis direction from the reference line 44 passing through the center point coordinates Ncj and the center point coordinates Ncj is calculated. Then, the flag f of the point Pi satisfying PLi> R is set to f = remaining, and the flag f of the point Pi satisfying PLi ≦ R is cleared to f = (step S1).
9). By the processing in step S19, the portion indicated by hatching in FIG. 9C whose direction is different from the hatching direction in FIG. 9B is actually cut off in the simulation.

By the first processing of steps S16 to S19, the point P for the tool path data Nd1 is
The processing interference (uncut portion) check for No. 1 is completed.

Then, it is determined whether or not the parameter i is i = n (step S20).
i + 1 (step S21) as steps S16 to S1
The process of No. 9 is repeated until the parameter i becomes i = n ("YES" in step S20).

In steps S16 to S20, the tool trajectory data N
The processing interference (uncut portion) check processing for all points Pi at the interpolation reference point of d1 is completed.

Then, next, the parameter j is set to j = j + 1.
(Step S22), that is, the tool is scanned up to the ball end mill 1bc as a tool and the next interpolation reference point Ndi + 2, and the parameter j = j representing the last interpolation reference point Ndm.
m (step S2).
3) The flag f for the next interpolation reference point Nd2 is f =
An interference check is performed on the remaining points Pi remaining (“YE” in steps S13 to S20).
S)) is repeated until the parameter j becomes j = m, thereby completing the machining interference check for all tool path data Ndj.

As described above, the ball end mill 1bc is scanned along the path of the ball end mill 1bc with respect to the processing shape surface Sd, and the ball end mill 1bs and the point P are scanned.
By checking the interference with i, it is possible to extract the uncut portion of the point Pi.

Then, the point Pi where the uncut flag f is set to f = remaining is stored in the database 26 as cut check data Cd, and is converted into a figure such as an “X” mark, for example, so as to be processed. Output to the display 31 together with Sd (step S24).

As a result, the result of interference check (residual result) can be confirmed on the screen of the display 31.

FIG. 10 shows an example of the result of the interference check on the screen of the display 31. The figure shows that, after stepwise feeding the φ30 ball end mill 1bc in the direction of the arrow 52 with respect to the processing shape surface Sd and performing the processing scanning in the direction of the arrow 51, the entire surface of the processing shape surface Sd is roughly cut. The state of the remaining point Pi (interference result) is shown. In the case of the rough cutting by the ball end mill 1bc of φ30, the upper end 1
Since it is cut down to about mm, the entire surface is left uncut.
The “X” mark indicates a point Pi generated on the surface of the processed shape surface Sd.

FIG. 11 shows a φ30 ball end mill 1b.
With respect to the processed shape surface Sd after the processing interference check processing in step c, the φ16 ball end mill 1bc is step-transformed in the direction of arrow 51 while being processed and scanned in the direction of arrow 52 to thereby obtain the processed shape surface Sd. This shows the remaining state (interference result) of the point Pi after the entire surface has been finish-cut. In FIG. 11, as shown in FIG. 12 showing the AA cross section, the size of the concave portion in the processing shape surface Sd is 4
Since it is R, the blade portion of the ball end mill 1bc does not reach that portion, and the portion becomes an uncut portion 53. Other white portions are the desired cut portions 54.

FIG. 13 shows a φ16 ball end mill 1b.
By performing step scanning of the ball end mill 1bc of φ6 in the direction of the arrow 51 with respect to the processed shape surface Sd after the completion of the processing interference check process in step c, the process scanning is performed in the direction of the arrow 52, thereby obtaining the processed shape surface Sd. It shows the remaining state (interference result) of the point Pi after the entire surface has been fine-finished. In FIG. 13, as shown in FIG. 14 showing the AA cross section, the uncut portion 53 (see FIG. 13) of the concave portion in the processed shape surface Sd is also a desired cut portion 54.

In the above description, in the machining interference check in step S6 in FIG.
bc is a detailed description.

Next, a detailed process when the tool 1 is the square end mill 1sc (see FIG. 5B) in the machining interference check in step S6 will be described.

FIG. 15 is a detailed flowchart of the remaining machining check in step S6 for the square end mill 1sc.

The processing in steps S31 to S36 is the same as the processing in steps S11 to S16 in FIG.
In the process of step S36, as shown in FIG. 16, when the point Pi is a point existing on the minus side in the Z′-axis direction from the tool tip coordinate represented by the tool path data Ndj, the flag of the point P1 is set. f is assumed to be f = remaining.

That is, if the point Pi is on the minus side on the Z 'axis from the reference line 43 (perpendicular to the Z' axis) passing through the interpolation reference point Ndj of the tip 1b of the square end mill 1sc, the flag f of the point Pi is set. Is assumed to be f = remaining.

Next, a point Pi existing on the plus side in the Z′-axis direction from the reference line 43 and the square end mill 1sc
Is calculated with respect to the axis 1a, that is, the Z ′ axis. Then, the flag f of the point Pi where Li> R (the radius of the square end mill 1sc) is left as f =
It is assumed that the flag f of the point Pi where i ≦ R is f = turned off (step S37). By the processing up to step S37, the interference check between the first interpolation reference point Nd1 and the point Pi by the blade of the square end mill 1sc is completed.

In the case of the square end mill 1sc, the coordinates of the center point coordinates Ncj and the coordinates of the interpolation reference point Ndj can be considered to be the same.

The remaining steps S38 to S42 are interference checks for all tool path data Ndj, and are performed in steps S20 to S20 in the flowchart of FIG.
Since the processing is the same as the processing in 24, the description thereof is omitted.

The above is a detailed description of the case where the tool 1 is a square end mill 1sc in the machining interference check in step S6 in FIG. In addition, since the drawing becomes complicated, the processed shape surface Sd is not drawn in FIG. 16, but it is needless to say that it can be considered in the same manner as in FIG. 9.

FIG. 17 is a detailed flowchart of the remaining machining check in step S6 in FIG. 4 when the tool 1 is the radius end mill 1rc.

In FIG. 17, steps S51 to S57
The processing up to is the same as the processing of steps S11 to S16 in FIG. In the process of step S56,
As shown in FIG. 18A, when the point Pi is a point existing on the minus side in the Z′-axis direction from the tool tip coordinates represented by the tool path data (also referred to as tool tip point coordinates) Ndj, the point Pi is set. Is set to f = remaining.

That is, when the point Pi is located on the minus side on the Z 'axis from the reference line 43 (perpendicular to the Z' axis) passing through the interpolation reference point Ndj of the tip 1b of the radius end mill 1rc, the flag f of the point Pi is set. Is assumed to be f = remaining.

Next, the radius end mill 1rc is raised to the plus side in the Z'-axis direction by the radius R of the bottom surface R of the corner portion br, and the center point coordinates N of the radius end mill 1rc are raised.
cj (see FIG. 18B) is obtained (step S57). In addition, since the drawing becomes complicated, the processing shape surface Sd is not drawn in FIG. 18, but it is needless to say that it can be considered in the same manner as in FIG. 9.

Next, a point Pi existing on the plus side in the Z′-axis direction from the reference line 43 passing through the tool tip point coordinates Ndj.
And the axis 1a of the radius end mill 1rc,
The distance Li from the Z ′ axis is calculated. And Li> R
The flag f of the point Pi for which 1 {R1 = (D−2R) / 2} is left as f = point Pi where Li ≦ R1
Flag f is turned off (step S58). By the process in step S58, the portion shown by hatching in FIG. 18B is removed by simulation. Next, the distance Lai between the point Pi where the flag f remaining on the plus side in the Z′-axis direction from the reference line 44 passing through the center point coordinates Ncj and f = remaining and the Z′-axis (axis 1a). Is calculated. And the distance Lai is smaller than the radius of the radius end mill 1rc, that is, L
It is assumed that the flag f of the point Pi where ai ≦ D / 2 is f = turned off (step S59). By the process in step S59, the portion shown by hatching in FIG. 18C is removed by simulation.

By the processing up to step S59, FIG.
The hatched portion 61 indicated by D is a portion to be desirably cut, and a portion other than the hatched portion 61 is an uncut portion 62, that is, a portion where a point Pi where the cutting flag f is f = remaining exists.

Next, the distance Lbi between the point Pi where the flag f is set to f = remaining and the center coordinate point rpc of the bottom R portion br of the radius end mill 1rc (FIG. 18E)
) Is calculated, and the flag f of the point Pi satisfying Lbi ≦ R (R of the bottom R portion) is set to f = turn off. By this processing, the interference check in the vicinity of the corner bottom surface R portion br is completed, and all the interference checks on the specific tool path data Ndj of the radius end mill 1rs are completed.

A part of the processing in steps S58 to S60 will be described in more detail with reference to FIG.

As described above, the radius end mill 1rs has two straight portions (cylindrical portions) having diameters D and D1 = (D-2R).
1 = Tool path data Nd at the straight part of (D-2R)
A check is performed up to the reference line 43 passing through j, that is, up to the 10 portion (corresponding to step S58. In FIG. 19, a portion indicated by hatching at the lower left in FIG. 19). Next, a check is performed up to the reference line 44 passing through the center point coordinates Ncj in the straight portion having a diameter of D, that is, up to the portion 11 (corresponding to step S59. In FIG. ). And finally, for the corner bottom surface R portion br, the circumference 6 formed by the center coordinate point rpc
3 is divided into predetermined parts, for example, 64 parts, and the center coordinate point rpc of the corner bottom surface R part br is divided into the division point center coordinate points rpc.
And a check between the point Pi.

[0092] As described above, in the machining interference check in step S6 of FIG.
This is a detailed description in the case of c.

As described above, according to the above-described embodiment, it is possible to check the cutting state of the machined surface Sd by the tool path data Nd which is five-axis NC data by simulation. That is, first, the processing shape surface data Sd is read from the database 25, and the point data Pi is generated for the processing shape surface Sd based on the processing shape surface data Sd. The tool path data Nd is read from the database 23, and the axial direction Z 'of the tool 1 is calculated (extracted). Further, tool data Td including parameters such as the type and diameter of the tool 1 is read. Then, the position of the tool 1, that is, the tool path data N
The local coordinate system based on d is recognized, and the coordinates of the above point data Pi are converted into the local coordinate system. After that, by calculating the distance between the tool path data Nd and the point data Pi according to the type of the tool 1, the processing interference check processing of the cutting can be performed.

For this reason, the quality of the 5-axis NC data Nd for providing a tool path to the machined surface Sd of a work such as a press die to be cut or ground can be determined without actually cutting the work. Can be easily checked by the simulation operation of the tool 1 with respect to. In addition, the above-described machining interference check processing is not limited to the three-axis orthogonal coordinate system with respect to the axial direction of the tool 1, and furthermore,
Since it is possible to cope with an arbitrary shape range of the tool 1, it can be said that the method is a general-purpose finding method of the uncut portion of the machining shape surface Sd with respect to the 5-axis NC data Nd. In addition, the processing surface S
By displaying on the screen of the display 31 the uncut data (point group whose position is designated by the point data Pi where the flag f is f = remaining) on d, the uncut data is visually and intuitively displayed. The effect of being able to recognize is also achieved.

The present invention is not limited to the above-described embodiment, but may adopt various configurations without departing from the gist of the present invention.

[0096]

As described above, according to the present invention, the 5-axis NC with respect to the machining shape surface of an arbitrary end mill such as a ball end mill, a square end mill, and a radius end mill mounted on a 5-axis NC machine tool.
The effect that the simulation of the uncut data can be easily performed is achieved.

Since the uncut portion can be checked by simulation, it is not necessary to prepare a test piece for test cutting as in the prior art, and the effect of reducing the cost for uncut portion check can be achieved. Is done. That is, the number of steps required to check the quality of the 5-axis NC data for cutting can be significantly reduced as compared with the related art.

Further, since the distance between the blade portion of the tool and the point group is calculated in the local coordinate system, the effect that the calculation time can be shortened is also achieved.

Moreover, as a result, the created 5-axis NC
The effect of improving the reliability and quality of data is also obtained.

The simulation according to the present invention can be applied to end mills of various shapes, such as a square end mill, a radius end mill, etc., which were not possible in the past.

Further, after the simulation, by displaying a point group whose position is designated by the uncut data on the processed shape surface displayed on the display, the uncut data can be visually and intuitively recognized. This effect is also achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a head portion of a general 5-axis NC machine tool.

FIG. 2 is a diagram provided for explaining a tilt angle of a tool.

FIG. 3 is a block diagram showing a configuration of an NC data check system to which the present invention is applied.

FIG. 4 is a flowchart showing an overall and schematic processing flow according to the embodiment of the present invention.

FIG. 5A is a diagram showing a configuration of a ball end mill;
FIG. 5B is a diagram showing a configuration of a square end mill, and FIG.
FIG. 2 is a diagram showing a configuration of a radius end mill.

FIG. 6 is a diagram showing a structure of point data.

FIG. 7 is a diagram illustrating a five-axis actuated ball end mill with respect to a machined shape surface and used for explaining a reference coordinate system and a local coordinate system.

FIG. 8 is a flowchart provided to explain a remaining machining check process when the tool is a ball end mill.

FIG. 9A is a diagram provided for explaining a remaining machining check process when the ball end mill is at the original position, FIG. 9B;
FIG. 9C is a diagram for explaining the case where the distance between the axis and the point is calculated and the uncut portion is checked when the ball end mill is located at the position where the ball end mill is raised by the radius. FIG. FIG. 11 is a diagram provided for describing a case where a distance between a tip coordinate point at a position raised by a distance and a point is calculated and the remaining portion is checked.

FIG. 10 is a view showing the uncut result when rough cutting is performed with a φ30 ball end mill.

FIG. 11 is a view showing a result of uncut portion when finishing by a ball end mill of φ11.

FIG. 12 is a schematic sectional view taken along line AA in FIG.

FIG. 13 is a view showing the uncut result when precision finish cutting is performed with a φ6 ball end mill.

FIG. 14 is a schematic sectional view taken along line AA in FIG.

FIG. 15 is a flowchart provided to explain a remaining machining check process when the tool is a square end mill.

FIG. 16 is a diagram provided for explanation of a process for checking uncut portions of a square end mill.

FIG. 17 is a flowchart provided to explain a remaining machining check process when the tool is a radius end mill.

FIG. 18A is a view used for explaining the uncut portion check processing when the radius end mill is at the original position, and FIGS. 18B and 18C are views in which the radius end mill is at a position raised by a radius, respectively. FIG. 18 is a diagram for explaining a case in which the distance between the axis and the point is calculated and the uncut portion is checked based on different criteria.
FIG. 18D is a diagram used for explaining a processing result based on FIGS. 18A to 18C, and FIG. 18E is a diagram used for explaining an uncut remaining check by the corner bottom surface R.

FIG. 19 is a diagram which is used for detailed description of a check for uncut portions by the corner bottom surface R.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Tool 1a ... Shaft 1b ... Tool tip 1bc ... Ball end mill 1sc ... Square end mill 1rc ... Radius end mill 11 ... Head 21 ... NC data check system 22 ... Control part Cd ... Sharpness check data Nd ... Tool path data Sd ... Processing shape surface Data Td: Tool data P, Pi: Point data (point data) i: Address number f: Uncut flag

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideyuki Horii 1-10-1 Shinsayama, Sayama City, Saitama Prefecture Honda Engineering Co., Ltd. (72) Inventor Kotaro Tanaka 1-10-1 Shinsayama, Sayama City, Saitama Prefecture Honda Engineering (56) References JP-A-7-64616 (JP, A) JP-A-3-157707 (JP, A) JP-A-63-119934 (JP, A) JP-A-63-18408 (JP, A) A) JP-A-6-28020 (JP, A) JP-A-3-290708 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G05B 19/18-19/46 B23Q 15 / 00-15/28

Claims (2)

(57) [Claims] 1. An XYZ orthogonal 3 axis at a predetermined pitch on a processing shape surface.
A point group represented by data based on the origin of the coordinate system is generated, and the XYZ coordinates of the tip of the tool and the axis of the tool are set to Y.
Consists of a tilt viewed from the Z plane and a tilt viewed from the XZ plane
In a method of checking 5-axis NC data, in which a cutting state by a tool path represented by 5-axis NC data is checked by simulation, a tool attribute is set, and the inclination of the tool is extracted from the 5-axis NC data to obtain the tool. Recognizing a local coordinate system based on the position of the point; converting the data for generating the point cloud into data based on the local coordinate system; and when scanning the tool Te, the interference with the point group and the tool
When the tool is moved in the tilt direction on the local coordinate system
Checking the distance based on the distance between the cutting edge of the tool and the point group, and extracting uncut points of the point group. 2. A method for extracting uncut points of the point group.
After the step , the position is specified by the data of the uncut point on the machined shape surface.
2. The method for checking 5-axis NC data according to claim 1, further comprising the step of displaying a point group defined .