DE112021007120T5 - DEVICE FOR MODIFYING A MACHINING PROGRAM, METHOD FOR MODIFYING A MACHINING PROGRAM AND MACHINING SYSTEM - Google Patents

Abstract

A device (11) for modifying a machining program modifies a machining program (4) for machining a machine tool by correcting a tool path, which is a path on which a tool is moved by the machine tool. The device (11) for modifying a machining program includes: a unit (12) for calculating the first feature amount, which obtains a first feature amount that represents a feature of a command point on the tool path, the command point being a position of the tool in a control period of the machine tool represents; a similar point calculating unit (13) which selects a target path for which a correction is to be made and an adjacent path adjacent to the target path from a plurality of the tool paths arranged in a direction different from a direction of movement on the tool path , and obtains a similar point from a plurality of command points on the adjacent trajectory based on the first feature amount of the command point on the target trajectory and the first feature amount of the command point on the adjacent trajectory, the similar point being a command point similar to the command point on the target trajectory; and a correction unit (14) that corrects the target trajectory based on the similar point.

Description

Area

The present disclosure relates to an apparatus for modifying a machining program, a method for modifying a machining program, and a machining system designed to modify a machining program.

background

For machining to be performed by a numerically controlled machine tool, a numerical control machining program is used, the numerical control machining program being configured in which a movement command for moving a workpiece or tool on a path has been predetermined. Hereafter, the numerically controlled machine tool is simply referred to as a “machine tool”. The numerical control machining program is simply referred to as the “machining program”.

When machining a freeform surface, many machining programs are generated by approximating a curved tool path around very small line segments based on a Computer Aided Manufacturing (CAM) function. When a tool path is represented by continuous, very small line segments, the shape of the tool path may change due to the effect of an error introduced in the calculation based on the CAM function. When a tool path changes in shape, an inconsistency in shape caused between adjacent tool paths in a direction perpendicular to a direction of movement on the tool paths can result in scratches or gouges on a machined surface, resulting in a reduction in the quality of the machined surface.

As a technique for improving the quality of the machined surface, which may decrease due to inconsistencies in shape between tool paths, Patent Literature 1 proposes a technique for correcting command points on a plurality of tool paths by smoothing preparation for each of the tool paths. A machining program modification apparatus disclosed in Patent Literature 1 reduces inconsistency in shape between adjacent tool paths by smoothing the tool paths in a direction perpendicular to a moving direction on the tool paths.

citation list

Patent literature

Patent Literature 1: Japanese Patent Laid-Open No. 2020-67863

Short presentation

Technical problem

In the conventional technique according to Patent Literature 1, for an uneven portion at a position adjacent to a tool path on a machined surface, smoothing may result in an error in the tool path with respect to the machined surface. In order to avoid an error in the tool path caused by correction, a worker performing work to modify a machining program may preset a portion where no correction is required. Alternatively, the machining program modification apparatus may additionally include processing of monitoring the curvature or the like of the machined surface so that no correction is made when it is determined that correction is not required. It is difficult for the worker to set a section where no correction is required because of the heavy load on the worker. Furthermore, when the machining program modification apparatus determines whether correction is required or not to make no correction when it is determined that no correction is required, the inconsistency in shape between adjacent tool paths may further increase. As described above, there is a problem in the conventional technique that it is difficult to improve the quality of the machined surface.

The present disclosure has been made with the above circumstances in mind, and one of its objects is to provide a machining program modification apparatus that can improve the quality of a machined surface.

the solution of the problem

In order to solve the above-mentioned problem and achieve the object, the present disclosure provides a machining program modification apparatus for modifying a machining program by correcting a tool path, which is a path on which a tool is moved by a machine tool, the machining program is configured to execute machining of the machine tool, wherein the machining program modification device comprises: a unit for calculating the first feature amount to obtain a first feature amount representing a feature of a command point on the tool path, the command point being a position of the tool in a control period of the machine tool; a similar point calculating unit for selecting a target path to be corrected and an adjacent path adjacent to the target path from a plurality of the tool paths arranged in a direction other than a moving direction on the tool path, and one obtain a similar point from a plurality of command points on the adjacent trajectory based on the first feature amount of the command point on the target trajectory and the first feature amount of the command point on the adjacent trajectory, the similar point being a command point similar to the command point on the target trajectory; and a correction unit for correcting the target trajectory based on the similar point.

Advantageous effects of the invention

The machining program modification apparatus according to the present disclosure has the advantageous effect that it can improve the quality of a machined surface.

Brief description of the drawings

• 1 is a diagram illustrating a machining program modification apparatus according to a first embodiment and a machining system connected to the machining program modification apparatus.
• 2 is a diagram illustrating a functional configuration of the machining program modification apparatus according to the first embodiment.
• 3 is a diagram illustrating an example of tool paths to be corrected by the machining program modification apparatus according to the first embodiment.
• 4 Fig. 10 is a flowchart illustrating a flow process of the machining program modification apparatus according to the first embodiment.
• 5 is a diagram for describing a first feature amount to be calculated by a first feature amount calculating unit of the machining program modification apparatus according to the first embodiment.
• 6 Fig. 10 is a diagram for describing selection of a target path and adjacent paths by a similar point calculating unit of the machining program modification apparatus according to the first embodiment.
• 7 is a diagram for describing a method of calculating a similar point by the similar point calculating unit of the machining program modification apparatus according to the first embodiment.
• 8th Fig. 10 is a diagram illustrating an example of similar points calculated by the similar point calculating unit of the machining program modification apparatus according to the first embodiment.
• 9 Fig. 10 is a flowchart illustrating a flow process of the similar point calculation unit serving as a component of the machining program modification apparatus according to the first embodiment.
• 10 Fig. 10 is a diagram for describing the creation of a line of similar points by a correction unit of the machining program modification apparatus according to the first embodiment.
• 11 Fig. 10 is a flowchart illustrating a flow process in which a route of similar points is created, which is executed by the correction unit of the machining program modification apparatus according to the first embodiment.
• 12 Fig. 10 is a diagram for describing an example of the correction of a tool path carried out by the correction unit of the machining program modification apparatus according to the first embodiment.
• 13 is a diagram illustrating a functional configuration of a machining program modification apparatus according to a second embodiment.
• 14 is a diagram illustrating an example of tool paths to be corrected by the machining program modification apparatus according to the second embodiment.
• 15 is a diagram for describing a second feature amount to be calculated by a second feature amount calculating unit of the machining program modification apparatus according to the second embodiment.
• 16 is a diagram for describing a method for classifying a group of tool paths into two or more clusters by a clustering unit of the machining program modification apparatus according to the second embodiment.
• 17 is a diagram illustrating an example of a result of classification performed by the clustering unit of the machining program modification apparatus according to the second embodiment.
• 18 Fig. 10 is a flowchart illustrating a flow process of a similar point calculation unit serving as a component of the machining program modification apparatus according to the second embodiment.
• 19 Fig. 10 is a flowchart illustrating a flow process in which a route of similar points is created, which is executed by a correcting unit of the machining program modification apparatus according to the second embodiment.
• 20 is a diagram illustrating a machining system according to a third embodiment.
• 21 is a diagram showing an example of a hardware configuration for implementing the machining program modification apparatus according to the first or second embodiment.
• 22 is a flowchart illustrating a flow process in which the machining program modification apparatus according to the first or second embodiment simulates machining.

Description of embodiments

Below, a device for modifying a machining program, a method for modifying a machining program and a machining system according to embodiments will be described in more detail with reference to the drawings.

First embodiment.

1 is a diagram illustrating a machining program modification apparatus 11 according to a first embodiment and a machining system 1 connected to the machining program modification apparatus 11. The machining system 1 is a system configured to machine a workpiece 10 by controlling a machine tool 7, which is a device to be controlled. The machine tool 7 processes the workpiece 10 with a tool 9 while the tool 9 is moved relative to the workpiece 10.

The machining system 1 includes a CAM device 3 and a numerical control device 5, wherein the CAM device 3 is a device for creating a machining program and the numerical control device 5 is configured to control the machine tool 7. The CAM device 3 is a computer system in which CAM software has been installed. The CAM device 3 generates a machining program 4 for machining using the tool 9 based on a computer-aided design (CAD) model 2. The CAD model 2 refers to shape data that specifies a target shape.

The numerical control device 5 generates a control signal 6 by executing the machining program 4. The numerical control device 5 transmits the generated control signal 6 to a drive unit 8 of the machine tool 7. The drive unit 8 includes a motor and a servo amplifier, the motor being the tool 9 drives and the servo amplifier is configured to control the motor according to the control signal 6. The motor and the servo amplifier are not illustrated in the figure. The machine tool 7 processes the workpiece 10 by driving the tool 9 in accordance with the control signal 6.

The machining program modification device 11 is connected to each of the CAM device 3 and the numerical control device 5 such that the device 11 can communicate with each of the devices 3 and 5. Communication can be wired or wireless. The machining program modification device 11 detects the machining program 4 generated by the CAM device 3 and modifies the machining program 4. The machining program modification device 11 transmits the modified machining program 4 to the numerical control device 5. The numerical control device 5 controls the machine tool 7 based on the modified machining program 4.

A configuration of the device 11 for modifying a machining program is described below. 2 is a diagram illustrating a functional configuration of the machining program modification apparatus 11 according to the first embodiment. The device 11 for modifying a machining program modifies the machining program 4 by correcting a tool path. The tool path is a path along which the tool 9 is moved by the machine tool 7, and is a path along which the tool 9 is moved with respect to the workpiece 10.

The machining program modification device 11 includes a first feature amount calculation unit 12, a similar point calculation unit 13, and a correction unit 14. The first feature amount calculation unit 12 obtains a tool path and a plurality of by analyzing the machining program 4 Command points arranged on the tool path. Each command point represents a position of the tool 9 in a control period of the machine tool 7. The unit 12 for calculating the first feature amount receives a first feature amount for each of the plurality of command points, which represents a feature of the command point on the tool path. The first feature amount calculation unit 12 outputs tool path data and a result of the first feature amount calculation to the similar point calculation unit 13.

The unit 13 for calculating a similar point selects a target path to be corrected and an adjacent path adjacent to the target path from a plurality of tool paths arranged in a direction different from a direction of movement on the tool path. The similar point calculation unit 13 obtains a similar point among the plurality of command points on the adjacent trajectory based on a first feature amount of a command point on the target trajectory and a first feature amount of a command point on the adjacent trajectory, the similar point being a command point similar to the command point is on the target track. The similar point calculation unit 13 outputs tool path data and similar point data to the correction unit 14.

The correction unit 14 corrects the target trajectory by correcting the command point on the target trajectory based on the similar point. The correction unit 14 generates a modified machining program 15 by correcting the target path. The modified machining program 15 is the machining program 4, which was modified by correcting the target path. The machining program modification device 11 transmits the modified machining program 15 to the numerical control device 5.

3 is a diagram showing an example of tool paths to be corrected by the machining program modification apparatus 11 according to the first embodiment. 3 shows an example of a target shape 20 and an example of a plurality of tool paths 21 for machining the workpiece 10 in the target shape 20. An x-axis, a y-axis and a z-axis are three axes that run perpendicular to one another. In 3 is a hatched section of the target shape 20 with oblique lines, a machined surface to be machined by the machine tool 7. The target shape 20 includes a machined surface PS, which is a free-form surface. The plurality of tool paths 21 are arranged on the machined surface of the target shape 20 in a direction different from a direction of movement on the tool paths 21. The three in 3 Tool paths 21 illustrated are arranged in a direction perpendicular to the directions of movement on the tool paths 21. In 3 Each tool path 21 is shown by a dashed line. The machine tool 7 moves the tool 9 one after the other on each of the tool paths 21.

In 3 is a number of command points 22 on each tool path 21 shown by black dots. The CAM device 3 generates the machining program 4 in which a curvature along a free-form surface is approximated by very small line segments. A line segment between the command points 22 represents a very small line segment. Each tool path 21 is represented by continuous, very small line segments.

The operation of the device 11 for modifying a machining program is described below. 4 is a flowchart illustrating a flow process of the machining program modification apparatus 11 according to the first embodiment. In step S1, the device 11 for modifying a machining program calculates a first feature amount for each of the command points 22 on the tool path 21. Details of the first feature amount will be described later.

In step S2, device 11 for modifying a machining program selects a target path and an adjacent path from the plurality of tool paths 21. In step S3, the machining program modification device 11 obtains a similar point for a target command point based on a first feature amount of the target command point and a first feature amount of a command point on the adjacent path. The target command point is a command point on the target trajectory. In step S4, the machining program modification device 11 corrects the target command point based on the similar point. The device 11 for modifying a machining program generates the modified machining program 15 in accordance with the method described above.

i

Befehlspunktnummer

N

Anzahl der Befehlspunkte auf der Werkzeugbahn: 1

pi

Matrix zur Darstellung der Koordinaten des i-ten Befehlspunktes auf der Werkzeugbahn

P

Matrix zur Darstellung der Koordinaten der einzelnen Befehlspunkte auf der Werkzeugbahn

An operation of the unit 12 for calculating the first feature amount will be described below. 5 is a diagram for describing the first feature amount calculated by the first feature amount calculating unit 12 of the machining program modification apparatus 11 according to the first embodiment. The first feature amount is, for example, coordinates of the command point 22. The first feature amount calculating unit 12 calculates coordinates as the first feature amount based on the following expression (1). The first feature amount calculation unit 12 calculates, for each of the plurality of tool paths 21, coordinates of each command point 22 on the tool path 21. Note that a command point number is a sequential number assigned to each of the command points 22 on each tool path 21 sequentially from a starting point 23 is assigned to the tool path 21. The starting point 23 is a 0th command point 22.
Formula 1: $$\begin{array}{l}{p}_i=\left[\begin{array}{ccc}{p}_{xi}& p_{yi}& p_{\mathrm{e.g}i}\end{array}\right],i=\mathrm{0,1,2}\cdots ,N\\ P={\left[\begin{array}{ccccc}{p}_0{}^T& p_1{}^T& p_2{}^T& \cdots & p_N{}^T\end{array}\right]}^T\\ =\left[\begin{array}{ccc}{p}_{x0}& p_{y0}& p_{\mathrm{e.g}0}\\ p_{x1}& p_{y1}& p_{\mathrm{e.g}1}\\ p_{x2}& p_{y2}& p_{\mathrm{e.g}2}\\ ⋮& ⋮& ⋮\\ p_{xN}& p{y}_N& p_{\mathrm{e.g}N}\end{array}\right]=\left[\begin{array}{ccc}{p}_x& p_y& p_{\mathrm{e.g}}\end{array}\right]\end{array}$$

i

Command point number

N

Number of command points on the tool path: 1

pi

Matrix to represent the coordinates of the ith command point on the tool path

P

Matrix for displaying the coordinates of the individual command points on the tool path

Δpi

Betrag von Bewegung auf der Werkzeugbahn am i-ten Befehlspunkt

Δp

Matrix zur Darstellung des Betrags von Bewegung an jedem Befehlspunkt auf der Werkzeugbahn

li

Länge des sehr kleinen Liniensegments, das den i-ten Befehlspunkt und den (i-1)-ten Befehlspunkt verbindet

The first feature amount can be, for example, an amount of movement at the command point 22 on the tool path 21. As in 5 As illustrated, an amount 24i of movement at an i-th command point 22i corresponds to an amount of movement of the tool 9 between the command point 22i and an (i-1)th command point 22(i-1). The first feature amount calculating unit 12 calculates the amount of movement for each command point 22 on the tool path 21 based on the following expression (2). The first feature amount calculating unit 12 calculates a vector representing the amount of movement. Alternatively, to calculate the first feature amount, the unit 12 may calculate the length of the very small line segment. The length of the very small line segment represents a value of the amount of movement.
Formula 2: $$\begin{array}{l}\Delta p_i=\left[\begin{array}{ccc}{p}_{xi}-p_{x\left(i-1\right)}& p_{yi}-p_{y\left(i-1\right)}& p_{\mathrm{e.g}i}-p_{\mathrm{e.g}\left(i-1\right)}\end{array}\right],i=\mathrm{1.2,}\cdots ,N\\ \Delta P={\left[\begin{array}{ccccc}{0}^T& \Delta p_1{}^T& \Delta p_2{}^T& \cdots & \Delta p_N{}^T\end{array}\right]}^T\\ l_i=\Vert p_i-p_{i-1}\Vert ,i=\mathrm{1.2,}\cdots ,N\end{array}$$

Δpi

Amount of movement on the tool path at the ith command point

Δp

Matrix representing the amount of movement at each command point on the tool path

li

Length of the very small line segment connecting the ith command point and the (i-1)th command point

lli

Kumulierte Länge der Werkzeugbahn am i-ten Befehlspunkt

ll

Vektor der kumulierten Länge der Werkzeugbahn

pG

Koordinaten des Schwerpunktes der Befehlspunkte auf der Werkzeugbahn

dx

Bewegungsabstand auf der Werkzeugbahn in x-Achsen-Richtung

dv

Bewegungsabstand auf der Werkzeugbahn in v-Achsen-Richtung

The first feature amount may be a cumulative length of the tool path 21 at the command point 22. As in 5 As illustrated, a cumulative length 25i at the i-th command point 22i is a length resulting from accumulation of the amounts of movement between the command points 22 from the starting point 23 to the command point 22i. It can also be said that the cumulative length 25i at the ith command point 22i is a length of the tool path 21 from the starting point 23 to the command point 22i. The first feature amount calculating unit 12 calculates the cumulative length for each command point 22 on the tool path 21 based on the following expression (3).
Formula 3: $$\begin{array}{l}l{l}_i={\displaystyle \sum _{j=1}^i{l}_j,i=\mathrm{1.2,}\cdots ,N}\\ ll={\left[\begin{array}{ccccc}0& l{l}_1& \mathrm{<figure-callout\; id="2"\; label="l\; l"\; filenames="DE112021007120T5\_0013.png,DE112021007120T5\_0019.png"\; state="\{\{state\}\}">l</figure-callout>}{l}_{}{}_2& \cdots & l{l}_N\end{array}\right]}^T\\ p_G=\frac{1}{N+1}{\displaystyle {\sum }_{i=0}^N{p}_i}=\left[\begin{array}{ccc}{p}_{Gx}& p_{Gy}& p_{G\mathrm{e.g}}\end{array}\right]\\ d_x=\text{Max}\left(p_x\right)-\text{min}\left(p_x\right),\left(d_x\ne 0\right)\\ d_y=\text{Max}\left(p_y\right)-\text{min}\left(p_y\right),\left(d_y\ne 0\right)\\ d_{\mathrm{e.g}}=\text{Max}\left(p_{\mathrm{e.g}}\right)-\text{min}\left(p_{\mathrm{e.g}}\right),\left(d_{\mathrm{e.g}}\ne 0\right)\end{array}$$

lli

Cumulative length of the tool path at the ith command point

ll

Tool path cumulative length vector

pG

Coordinates of the center of gravity of the command points on the tool path

dx

Movement distance on the tool path in the x-axis direction

dv

Movement distance on the tool path in the v-axis direction

p̂l

Normalisierte Koordinaten des i-ten Befehlspunktes auf der

P̂

Matrix, die normalisierte Koordinaten jedes Befehlspunktes auf der Werkzeugbahn darstellt

The first feature amount may be normalized coordinates, a normalized amount of motion, or a normalized cumulative length. The first feature amount calculation unit 12 calculates normalized coordinates by dividing a coordinate value by an average value Coordinate values, one of their maximum values or the like. The first feature amount calculating unit 12 calculates normalized coordinates based on the following expression (4).
Formula 4: $$\begin{array}{l}{\widehat{p}}_i=\left[\begin{array}{ccc}\left(p_{xi}-p_{Gx}\right)/d_x& \left(p_{yi}-p_{Gy}\right)/d_y& \left(p_{\mathrm{e.g}i}-p_{G\mathrm{e.g}}\right)/d_{\mathrm{e.g}}\end{array}\right]\\ i=\mathrm{0,1,2,}\cdots ,N\\ \widehat{P}={\left[\begin{array}{ccccc}{\widehat{p}}_0{}^T& {\widehat{p}}_1{}^T& {\widehat{p}}_2{}^T& \cdots & {\widehat{p}}_N{}^T\end{array}\right]}^T\end{array}$$

p̂l

Normalized coordinates of the ith command point on the

P̂

Matrix representing normalized coordinates of each command point on the tool path

Normalisierter Betrag von Bewegung auf der Werkzeugbahn am i-ten Befehlspunkt

Matrix zur Darstellung des normalisierten Betrags von Bewegung an jedem Befehlspunkt auf der Werkzeugbahn

The first feature amount calculating unit 12 calculates a normalized amount of motion by dividing an amount of motion by an average of the amounts of motion, a maximum value thereof, or the like. The first feature amount calculating unit 12 calculates a normalized amount of motion based on the following expression (5).
Formula 5: $$\begin{array}{l}\widehat{\Delta p_i}=\Delta p_i/l_i,\left(l_i\ne 0\right),i=\mathrm{1.2,}\cdots ,N\\ \widehat{\Delta P}={\left[\begin{array}{ccccc}{0}^{\mathrm{<figure-callout\; id="1"\; label="T\; \Delta \; p"\; filenames="DE112021007120T5\_0017.png,DE112021007120T5\_0019.png"\; state="\{\{state\}\}">T</figure-callout>}}& {\stackrel{}{\Delta p_{}}}^{}{\widehat{{}_1}}^{\mathrm{<figure-callout\; id="2"\; label="T\; \Delta \; p"\; filenames="DE112021007120T5\_0013.png,DE112021007120T5\_0019.png"\; state="\{\{state\}\}">T</figure-callout>}}& {\stackrel{}{\Delta p_{}}}^{}{\widehat{{}_2}}^T& \dots & {\widehat{\Delta p_N}}^T\end{array}\right]}^T\end{array}$$

Normalized amount of movement on the tool path at the ith command point

Matrix representing the normalized amount of motion at each command point on the tool path

Normalisierte kumulierte Länge der Werkzeugbahn bis zum i-ten Befehlspunkt

Vektor der normalisierten kumulierten Länge der

The first feature amount calculation unit 12 calculates a normalized cumulative length by dividing a cumulative length by an average of the cumulative lengths, a maximum value thereof, or the like. The first feature amount calculating unit 12 calculates a normalized cumulative length based on the following expression (6).
Formula 6: $$\begin{array}{l}\widehat{l{l}_i}=l{l}_i/l{l}_N,\left(l_N\ne 0\right),i=\mathrm{1.2,}\cdots ,N\\ \widehat{ll}={\left[\begin{array}{ccccc}0& \widehat{\mathrm{<figure-callout\; id="1"\; label="l\; l"\; filenames="DE112021007120T5\_0017.png,DE112021007120T5\_0019.png"\; state="\{\{state\}\}">l</figure-callout>}{l}_{}{}_1}& \widehat{l{l}_2}& \cdots & \widehat{l{l}_N}\end{array}\right]}^T\end{array}$$

Normalized cumulative length of the tool path to the i-th command point

Vector of the normalized cumulative length of the

fi

Vektor des ersten Merkmalsbetrags des i-ten

δ, ε, ∈

Gewichtungskoeffizient des ersten

F

Matrix zur Darstellung des ersten Merkmalsbetrags

aller Befehlspunkte auf der Werkzeugbahn

The first feature amount may be multidimensional information including at least two of the normalized coordinates, the normalized amount of motion, and the normalized cumulative length. The first feature amount calculating unit 12 calculates the first feature amount, which is multidimensional information, based on, for example, the following expression (7).
Formula 7: $$\begin{array}{l}{f}_i=\left[\begin{array}{ccc}\delta {\widehat{p}}_i& \epsilon \widehat{\Delta p_i}& e\widehat{l{l}_i}\end{array}\right],i=\mathrm{0,1,2,}\cdots ,N,\\ \delta \ge \mathrm{0,}\epsilon \ge \mathrm{0,}\epsilon \ge \mathrm{0,}\delta +\epsilon +\epsilon \ge 2\\ F={\left[\begin{array}{ccccc}{f}_0{}^T& f_1{}^T& f_2{}^T& \cdots & f_N{}^T\end{array}\right]}^T\end{array}$$

fi

Vector of the first feature amount of the i-th

δ, ε, ∈

Weighting coefficient of the first

F

Matrix to represent the first feature amount

all command points on the tool path

Note that the first feature amount is not necessarily limited to those described in the first embodiment, as long as the first feature amount is an amount representing the feature of the command point 22 on the tool path 21.

An operation of the unit 13 for calculating a similar point will be described below. 6 Fig. 10 is a diagram for describing the selection of a target path and adjacent paths by the similar point calculating unit 13 of the machining program modification apparatus 11 according to the first embodiment. The unit 13 for calculating a similar point selects a target path 26 from a large number of the tool paths 21. In addition, the unit 13 selects adjacent paths 27 that are adjacent to the target path 26 to calculate a similar point. 6 shows an example of the target path 26 and the adjacent paths 27. The unit 13 for calculating a similar point selects each of the plurality of tool paths 21 in turn as the target path 26.

The similar point calculation unit 13 acquires from the first feature amount calculation unit 12 data on the first feature amount of each command point 22 on the target trajectory 26 and data on the first feature amount of each command point 22 on the adjacent tracks 27. The similar point calculation unit 13 Point maintains a correspondence relationship between each command point 22 on the target path 26 and each command point 22 on the adjacent paths 27, so that a cumulative distance error between the first feature amount data on the target path 26 and the first feature amount data on the adjacent paths 27 becomes minimal. The cumulative distance error is defined as an accumulated value of a distance error that represents a difference between the first feature amount of the command point 22 on the target trajectory 26 and the first feature amount of the command point 22 on the adjacent trajectory 27 for each command point 22 on the target trajectory 26. The similar point calculation unit 13 calculates as a similar point the command point 22 on the adjacent trajectory 27 in association with the command point 22 on the target trajectory 26 in the correspondence relationship in which the cumulative distance error is minimum.

An example of a method for calculating a similar point is described here. In the present example, the similar point calculating unit 13 recognizes each of the first feature amount data on the target trajectory 26 and first feature amount data on the adjacent lanes 27 as time series information and calculates a similar point by a dynamic time warping method. A method of calculating a similar point in the similar point calculating unit 13 is not necessarily limited to that described in the first embodiment.

7 is a diagram for describing a method of calculating a similar point by the similar point calculating unit 13 of the machining program modification apparatus 11 according to the first embodiment. The horizontal axis of an in 7 Illustrated diagram represents the command point 22 on the target trajectory 26. The vertical axis of the in 7 The illustrated diagram represents the command point 22 on the adjacent path 27. Each command point 22 is represented by a numerical value of (a command point number) + 1.

In 7 the command point 22 of “p” on the target path 26 and the command point 22 of “q” on the adjacent path 27 are assigned to each other. This assignment is represented as (p,q). In the in 7 In the illustrated diagram, a point 31 represents an association of (p,q). A point 32 represents an association (1,1) between starting points of the target trajectory 26 and the neighboring trajectory 27. A point 33 represents an association (N,M) between end points of the target path 26 and the neighboring path 27.

A point 34 represents an association (p,q+1) between the command point 22 of "p" on the target trajectory 26 and the command point 22 of "q+1" on the adjacent trajectory 27. A point 35 represents an association (p +1,q+1) between the command point 22 of “p+1” on the target path 26 and the command point 22 of “q+1” on the adjacent path 27. A point 36 represents an association (p+1,q ) between the command point 22 of “p+1” on the target trajectory 26 and the command point 22 of “q” on the adjacent trajectory 27. In the in 7 In the diagram illustrated, the options are a route from point 31 to point 33, an upward route with a direction from point 31 to point 34, a diagonal upper right route with a direction from point 31 to point 35 and a right route with a direction from point 31 to Point 36.

In the case of selecting the uplink from the point 31, the unit 13 for calculating a similar point determines a distance error between the command point 22 of “p” on the target trajectory 26 and the command point 22 of “q+1” on the adjacent trajectory 27 and adds the distance error obtained to a cumulative distance error from the point 32 to the point 31. In the case of selecting the diagonally upper right route from the point 31, the unit 13 for calculating a similar point determines a distance error between the command point 22 of “p+ 1" on the target path 26 and the command point 22 of "q+1" on the adjacent path 27 and adds the distance error obtained to the cumulative distance error from point 32 to point 31. In the case of selecting the right route from point 31 For calculating a similar point, the unit 13 determines a distance error between the command point 22 of “p+1” on the target path 26 and the command point 22 of “q” on the adjacent path 27 and adds the obtained distance error to the cumulative distance error from the point 32 to point 31.

The similar point calculation unit 13 calculates a distance such that a cumulative distance error from the point 32 to the point 33 is minimal by performing such calculation for each association between the point 32 and the point 33. One in 7 Illustrated dashed line represents an example of a result of calculating a distance that enables a cumulative distance error to be minimized. Such a route represents a correspondence relationship in which a cumulative distance error between each command point 22 on the target trajectory 26 and each command point 22 on the adjacent trajectory 27 becomes minimal. The similar point calculation unit 13 calculates as a similar point the command point 22 on the adjacent trajectory 27 in association with each command point 22 on the target trajectory 26 in the correspondence relationship in which the cumulative distance error can be minimized.

In the in 7 In the example shown, among the command points 22 on the adjacent path 27, each of the command point 22 of "q" and the command point 22 of "q+1" is a similar point for the command point 22 of "p". The similar point calculation unit 13 sets as a similar point either the command point 22 of "q" or the command point 22 of "q+1" which has a smaller distance error with respect to the command point 22 of "p". As just described, when two or more command points 22 are calculated as similar points for a single command point 22 on the target trajectory 26, the similar point calculation unit 13 sets a command point 22 with the smallest distance error of the command points 22 as the similar point.

8th Fig. 10 is a diagram showing an example of similar points calculated by the similar point calculating unit 13 of the machining program modification apparatus 11 according to the first embodiment. In 8th Each open point on the adjacent trajectory 27 represents a similar point 41 that corresponds to any one of a plurality of the command points 22 on the target trajectory 26. Each black dot on the adjacent track 27 represents a command point 22 that does not correspond to the similar point 41 among the command points 22 on the adjacent track 27. Each straight line 42 connecting the command point 22 on the target path 26 and the similar point 41 on the adjacent path 27 represents a correspondence between the command point 22 on the target path 26 and the similar point 41 on the adjacent path 27. An association between the command point 22 on the target path 26 and the similar point 41 on the adjacent path 27 represents an association between points that have similar features on the adjacent tool paths 21. In this way, the unit 13 assigns points with similar features on the adjacent tool paths 21 to calculate a similar point.

The similar point calculation unit 13 sets as a target command point 40 one of the plurality of command points 22 on the target trajectory 26 and calculates the similar point 41 corresponding to the target command point 40. The similar point calculation unit 13 sequentially sets each command point 22 on the target trajectory 26 as the target command point 40 and calculates the similar point 41 corresponding to each command point 22 on the target trajectory 26.

9 Fig. 10 is a flowchart illustrating a flow process of the similar point calculation unit 13 serving as a component of the machining program modification apparatus 11 according to the first embodiment. In step S11, the similar point calculation unit 13 selects the target trajectory 26 by reading data on the target trajectory 26 from the first feature amount calculation unit 12. In step S12, the similar point calculating unit 13 selects the adjacent trajectory 27 by reading data on the adjacent trajectory 27 from the first feature amount calculating unit 12.

In step S13, the similar point calculation unit 13 sets one of a plurality of command points 22 on the target trajectory 26 as the target command point 40. In step S14, the similar point calculation unit 13 calculates the similar point 41 for the target command point 40.

In step S15, the similar point calculation unit 13 determines whether or not the target command point 40 is the last command point 22 on the target trajectory 26. If the target command point 40 is not the last command point 22 on the target trajectory 26 (step S15, No), the similar point calculation unit 13 sets the command point 22 adjacent to the target command point 40 as a target command point 40 in step S16. The similar point calculation unit 13, after setting, performs an operation according to a process in step S14 for the target command point 40.

On the other hand, if the target command point 40 is the last command point 22 on the target path 26 (step S15, Yes), the similar point calculation unit 13 determines in step S17 whether or not the target path 26 is the last tool path 21 among all the tool paths 21 . If the target path 26 is not the last tool path 21 (step S17, No), the similar point calculation unit 13 selects the next target path 26 by receiving data on the next target path 26 from the first calculation unit 12 in step S18 characteristic amount reads. The similar point calculation unit 13 executes an operation for the next target trajectory 26 according to a process in step S12.

On the other hand, if the target path 26 is the last tool path 21 (step S17, Yes), the similar point calculation unit 13 finishes the process according to FIG 9 illustrated process. In this way, the similar point calculation unit 13 calculates the similar point 41 for each command point 22 on each of the plurality of tool paths 21.

An operation of the correction unit 14 will be described below. The correction unit 14 obtains the similar points 41 for each set of tool paths 21 adjacent to one another in the tool paths 21, thereby creating a route of similar points that connects a large number of the similar points 41 obtained. The correction unit 14 corrects the command point 22 on the target trajectory 26 based on the obtained distance of similar points.

The correction unit 14 corrects the target trajectory 26 by adjusting the position of the target command point 40 on the target trajectory 26 based on the created route of similar points. The correction unit 14 corrects the target trajectory 26 so that by adjusting the position of the target command point 40, an inconsistency in the shape of the target trajectory 26 with respect to the adjacent trajectory 27 is reduced. The term “inconsistency in shape” refers to a condition in which a difference in the shape of the tool path 21 occurs. Alternatively, the term “inconsistency in shape” refers to a condition in which a difference in shape between the tool paths 21 increases to the point that an allowable machining range is exceeded.

Here, in a stretch of similar points consisting of L command points 22, three consecutive command points 22 are shown as a kth command point 22, a (k+1)th command point 22 and a (k+2)th command point 22. The symbol “k” denotes an integer from 1 to L-2, where L is defined as L≥3. The degree of inconsistency in the form with respect to the k-th command point 22 to the (k+2)-th command point 22 is, for example, a distance between the (k+1)-th command point 22 and a distance through the k-th command point 22 and the (k+2)th command point 22 is shown.

10 is a diagram for describing the creation of a line 43 of similar points executed by a correction unit 14 of the machining program modification apparatus 11 according to the first embodiment. 10 illustrates a single route 43 of similar points passing through the target command point 40 on the target trajectory 26. In the 10 The five tool paths 21 illustrated are a subset of a large number of tool paths 21 arranged on the machined surface. The route 43 of similar points intersects the entirety of the tool paths 21. 10 illustrates a portion of the route 43 of similar points that intersects the five tool paths 21.

The similar point calculation unit 13 calculates, for each of the tool paths 21, the similar point 41 corresponding to the target command point 40 on the target path 26 by sequentially switching the tool path 21 selected as the target path 26. The command points 22, which have a relationship between the target command point 40 and the similar point 41, are connected by the straight line 42, as shown in FIG 8th illustrated, and the straight lines 42 are connected over the entire tool paths 21, thereby creating the route 43 of similar points. The correction unit 14 generates for everyone Command point 22 of the command points on the target trajectory 26 for which the similar point 41 was calculated, the route 43 of similar points.

11 is a flowchart illustrating a flow process in which the similar point route 43 is created by the correction unit 14 of the machining program modification apparatus 11 according to the first embodiment. In step S21, the correction unit 14 selects the target trajectory 26 by acquiring data on the target trajectory 26 from the similar point calculation unit 13. In step S22, the correction unit 14 sets one of the command points 22 on the target path 26 as the target command point 40.

The correction unit 14 acquires data on the similar point 41 corresponding to the target command point 40 from the similar point calculation unit 13. In step S23, the correction unit 14 adds the similar point 41 for the target command point 40 to the similar point route 43. If the first tool path 21 of the tool paths 21 is the target path 26, the correction unit 14 keeps the straight line 42 connecting the target command point 40 and the similar point 41 as an initial route 43 of similar points when creating. Each time the tool path 21 selected as the target path 26 is switched, the correction unit 14 adds the similar point 41 to the line 43 of similar points obtained therein. The correction unit 14 extends the line 43 of similar points by adding the similar point 41 to the line 43 of similar points.

In step S24, the correction unit 14 determines whether or not the similar point 41 added to the similar point route 43 is the command point 22 on the last tool path 21 among all the tool paths 21. If the similar point 41 is not the command point 22 on the last tool path 21 (step S24, No), the correction unit 14 sets the similar point 41 as the next target command point 40 in step S25. The correction unit 14 executes an operation according to the process of step S23 for the next target command point 40.

On the other hand, if the similar point 41 is the command point 22 on the last tool path 21 (step S24, Yes), the correction unit 14 determines whether or not the target command point 40 is the last command point 22 on the target path 26 in step S26. If the target command point 40 is not the last command point 22 on the target path 26 (step S26, No), the correction unit 14 sets the command point 22 next to the target command point 40 as a target command point 40 in step S27. The correction unit 14 executes an operation according to the process of step S23 for the next target command point 40.

On the other hand, if the target command point 40 is the last command point 22 on the target path 26 (step S26, Yes), the correction unit 14 determines whether or not the target path 26 is the last tool path 21 among all the tool paths 21 in step S28. If the target path 26 is not the last tool path 21 (step S28, No), the correction unit 14 selects the next target path 26 by reading data on the next target path 26 from the similar point calculation unit 13 in step S29. The correction unit 14 executes an operation according to the process in step S22 for the next target trajectory 26.

On the other hand, if the target path 26 is the last tool path 21 (step S28, Yes), the correction unit 14 ends the process according to FIG 11 illustrated process. In this way, the correction unit 14 generates the route 43 of similar points at each of the command points 22 on the plurality of tool paths 21.

12 is a diagram for describing an example of the correction of the tool path 21 carried out by the correction unit 14 of the machining program modification apparatus 11 according to the first embodiment. One in 12 Illustrated arrow line 47 represents the degree of inconsistency in the shape of the target trajectory 26 with respect to the adjacent trajectory 27. In Fig 12 In the example shown, the correction unit 14 generates a smoothed route 44 by smoothing the route 43 of similar points passing through the target command point 40 and switches the command point 22 on the target path 26 from the target command point 40 to a correction point 45 on the smoothed route 44. That is, the correction unit 14 adjusts the position of the command point 22 by moving the command point 22 to the smoothed route 44. In the 12 illustrated smoothed path 44 is a curve. The correction unit 14 smoothes the path 43 of similar points using, for example, a B-spline curve or a non-uniform rational B-spline curve (NURBS curve). It should be noted that the smoothed line 44 can be a straight line. The correction unit 14 can reduce the inconsistency in the shape of the target trajectory 26 with respect to the adjacent trajectory 27 by adjusting the position of the command point 22 on the target trajectory 26 based on the smoothed route 44.

In addition, the correction unit 14 can receive a plane 46 which runs through the target command point 40 and two command points 22 adjacent to the target command point 40 on the target path 26 in order to set the correction point 45 on the plane 46. The two command points 22 are a command point 22 which is adjacent to the target command point 40 in a direction of movement of the tool 9 and a further command point 22 which is adjacent to the target command point 40 in a direction opposite to the direction of movement of the tool 9. This means that the correction unit 14 can do the work caused by the successive command points 22 Obtain level 46 running on target path 26 and adjust the position of target command point 40 on level 46. As a result, the correction unit 14 can reduce the positional deviation of the correction point 45 from the plane 46 through which the target path 26 runs.

The machining program modification device 11 according to the first embodiment generates the modified machining program 15 while acquiring data on the tool path 21 from the machining program 4 provided by the machining system 1. Data on the tool path 21 from the machining system 1 can be transmitted to the device 11 for modifying a machining program, and it can generate the modified machining program 15 based on the data on the tool path 21 obtained thereby.

According to the first embodiment, the machining program modification device 11 obtains the similar point 41 corresponding to the command point 22 of the target path 26 based on the first feature amount of the command point 22 on the target path 26 and the first feature amount of the command point 22 on the adjacent path 27 and accordingly corrects the target path 26 based on the similar point 41. The machining program modification device 11 may perform correction by taking into account the correspondence between points having their respective similar features on the tool paths 21 adjacent to each other, by using the similar point 41 is used, which is obtained based on the first feature amount for the correction of the target trajectory 26. Consequently, the machining program modification apparatus 11 can reduce inconsistencies in the shape of the target path 26 with respect to the adjacent path 27. Furthermore, the machining program modification device 11 can reduce the occurrence of an error in the tool path 21 with respect to the machined surface due to the correction. As described above, the machining program modification device 11 has the advantageous effect of enabling improvement in the quality of the machined surface.

Second embodiment.

13 is a diagram illustrating a functional configuration of a machining program modification apparatus 11A according to a second embodiment. In the machining program modification apparatus 11A, a second feature amount calculating unit 51 and a clustering unit 52 have been made into the same configuration as that shown in FIG 2 illustrated configuration of the device 11 for modifying a machining program. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and a part of the configuration different from that of the first embodiment is mainly described.

The second feature amount calculation unit 51 obtains the tool path 21 by analyzing the machining program 4 and obtains a second feature amount representing the feature of the tool path 21. The clustering unit 52 divides a group of tool paths for machining the workpiece 10 into a plurality of clusters based on the second feature amount. The first feature amount calculation unit 12, the similar point calculation unit 13, and the correction unit 14 perform substantially the same processing as in the first embodiment on a plurality of tool paths 21 for each cluster. That is, the first feature amount calculation unit 12 calculates the first feature amount of each command point 22 on the tool path 21 for each of the tool paths 21 for each cluster. The similar point calculation unit 13 selects the target path 26 and the adjacent path for each cluster 27 to get the similar point 41. The correction unit 14 corrects the target trajectory 26 for each cluster.

14 is a diagram showing an example of the tool paths 21 to be corrected by the machining program modification apparatus 11A according to the second embodiment. 14 shows an example of a target shape 20A and an example of a group of tool paths for machining the workpiece 10 into the target shape 20A. A hatched area of the target shape 20A with oblique lines is a machined surface to be machined by the machine tool 7. The target shape 20A leg hold two machined surfaces PS1 and PS2, which are freeform surfaces. The machined surface PS1 and the machined surface PS2 are positioned apart from each other in the target shape 20A. In 14 Illustrated are six tool paths 21-1, 21-2, 21-3, 21-4, 21-5 and 21-6, which are the tool paths 21 that form the group of tool paths.

An operation of the unit 51 for calculating the second feature amount will be described below. 15 is a diagram for describing a second feature amount calculated by the second feature amount calculating unit 51 of the machining program modification apparatus 11A according to the second embodiment. The second feature amount calculating unit 51 calculates the second feature amount of each tool path 21 included in the group of tool paths.

For example, the second feature amount relates to coordinates of a center of gravity position 53 of the tool path 21, a main component 54 of the tool path 21, a main component vector of the tool path 21 or a tool path length 55. The main component 54 is an approximate straight line of the command points 22 on the tool path 21. The tool path length 55 is a length of the tool path 21 from its starting point 23 to its end point 25.

The second feature amount may be normalized coordinates of the center of gravity position 53. The second feature amount calculating unit 51 calculates normalized coordinates by dividing a coordinate value by an average of the coordinate values, a maximum value thereof, or the like. Likewise, the unit 51 for calculating the second feature amount can calculate a normalized main component 54, a normalized main component vector or a normalized tool path length 55 as the second feature amount. The second feature amount may be multidimensional information including at least two of the normalized coordinates, the normalized principal component 54, the normalized principal component vector, and the normalized tool path length 55. Note that the second feature amount is not necessarily limited to the amounts described in the second embodiment as long as the second feature amount is an amount representing the feature of the tool path 21.

An operation of the clustering unit 52 will be described below. 16 is a diagram for describing a method of classifying a group of tool paths into two or more clusters by the clustering unit 52 of the machining program modification device 11A according to the second embodiment. The clustering unit 52 acquires from the second feature amount calculating unit 51 data on each tool path 21 included in the group of tool paths and the second feature amount of each tool path 21. The clustering unit 52 classifies the group of tool paths based on the second acquired feature amounts into two or more clusters. For example, to classify the clustering unit 52, a method such as a k-means method or the method of a density-based spatial clustering of applications with noise (DBSCAN) can be used.

Here, assume that the clustering unit 52 acquires data on each of the coordinates of the center of gravity position 53, the main component 54, the main component vector and the tool path length 55 as the second feature amount data. With this assumption, the second feature amount includes 16 components, which include a centroid position coordinate (x), a centroid position coordinate (y), a centroid position coordinate (z), a principal component (x), a principal component (y), a principal component (z), a first principal component vector (x), a first principal component vector (y), a first principal component vector (z), a second principal component vector (x), a second principal component vector (y), a second principal component vector (z), a third principal component vector (x), a third principal component vector ( y), a third principal component vector (z) and the tool path length is 55. The symbol (x) denotes a component in the x-axis direction, the symbol (y) denotes a component in the y-axis direction, and the symbol (z) denotes a component in the z-axis direction. The first principal component vector, the second principal component vector and the third principal component vector are acquired, for example, through principal component analysis of data on command points on the tool path 21. The clustering unit 52 classifies the tool paths 21 by comparing the second feature amounts of the tool paths 21 in 16 dimensions.

The cluster unit 52 draws points on a graph that represent the second feature amounts of the tool paths 21 and defines regions of clusters on the graph so that points lying close to one another on the graph and whose distances from one another are relatively short are within the same range chen region that represents the area of a cluster. 16 shows an example of a mapping result in the case that the second feature amount has three components. Three axes of the in 16 illustrated diagram represent a first component, a second component and a third component, which are components of the second feature amount. Note that the number of components of the second feature amount is not necessarily limited to three and can be set to any number. In this way, the clustering unit 52 performs clustering so that the tool paths 21 with the second feature amounts close to each other are assigned to the same cluster.

In 16 a point 56-1 represents the second feature amount of the tool path 21-1. A point 56-2 represents the second feature amount of the tool path 21-2. A point 56-3 represents the second feature amount of the tool path 21-3. One point 56-4 represents the second feature amount of the tool path 21-4. A point 56-5 represents the second feature amount of the tool path 21-5. A point 56-6 represents the second feature amount of the tool path 21-6 in 16 In the example shown, the three points 56-1, 56-2 and 56-3 are in a region 57-1 which represents a first cluster, and the three points 56-4, 56-5 and 56-6 are in a region 57-2, which represents a second cluster. As a result, the clustering unit 52 classifies the three tool paths 21-1, 21-2 and 21-3 into the first cluster and classifies the three tool paths 21-4, 21-5 and 21-6 into the second cluster.

17 is a diagram showing an example of a result of classification performed by the clustering unit 52 of the machining program modification apparatus 11A according to the second embodiment. The tool paths 21-1, 21-2 and 21-3 classified into a first cluster 58-1 are the tool paths 21 on the machined surface PS1. The tool paths 21-4, 21-5 and 21-6 classified into a second cluster 58-2 are the tool paths 21 on the machined surface PS2. In this way, the clustering unit 52 classifies the tool paths 21 in a group of tool paths for the workpiece 10 into clusters of the tool paths 21 whose features are common to each other.

The unit 12 for calculating the first feature amount acquires data from the clustering unit 52 on each tool path 21 for each cluster. The first feature amount calculation unit 12 calculates the first feature amount of each command point 22 on the tool path 21 for each of a plurality of tool paths 21 of each cluster.

18 Fig. 11 is a flowchart illustrating a flow process of the similar point calculation unit 13 serving as a component of the machining program modification apparatus 11A according to the second embodiment. In step S31, the similar point calculation unit 13 selects a plurality of the tool paths 21 of a target cluster by acquiring data on the plurality of tool paths 21 of the target cluster from the first feature amount calculation unit 12. The target cluster refers to a cluster for which a correction of the tool paths 21 is to be carried out.

In step S32, the unit 13 selects the target path 26 from the plurality of tool paths 21 of the target cluster for calculating a similar point. In step S33, the similar point calculation unit 13 selects the adjacent path 27 from the plurality of tool paths 21 of the target cluster.

In step S34, the similar point calculation unit 13 sets one of the plurality of command points 22 on the target trajectory 26 as the target command point 40. In step S35, the similar point calculation unit 13 calculates the similar point 41 for the target command point 40.

In step S36, the similar point calculation unit 13 determines whether or not the target command point 40 is the last command point 22 on the target trajectory 26. If the target command point 40 is not the last command point 22 on the target trajectory 26 (step S36, No), the similar point calculating unit 13 sets the command point 22 adjacent to the target command point 40 as a target command point 40 in step S37. The similar point calculation unit 13 performs a process according to the method of step S35 for the target command point 40 obtained by the determination.

On the other hand, if the target command point 40 is the last command point 22 on the target trajectory 26 (step S36, Yes), the similar point calculation unit 13 determines whether the target trajectory 26 is in step S38 in the target cluster the last tool path is 21 or not. If the target path 26 is not the last tool path 21 in the target cluster (step S38, No), the similar point calculation unit 13 selects the next target path 26 from the plurality of tool paths 21 in the target cluster in step S39. The similar point calculation unit 13 executes a process according to the process of step S33 for the next target trajectory 26.

On the other hand, if the target path 26 is the last tool path 21 in the target cluster (step S38, Yes), the similar point calculation unit 13 determines whether or not the target cluster is a last cluster for the workpiece 10 in step S40. If the target cluster is not the last cluster (step S40, No), the similar point calculation unit 13 selects a plurality of the tool paths 21 of the next target cluster in step S41 by obtaining data on the plurality of tool paths 21 of the next target cluster from the Unit 12 is recorded for calculating the first feature amount. The similar point calculation unit 13 executes a process according to the process of step S32 for the next target cluster.

On the other hand, if the target cluster is the last cluster for the workpiece 10 (step S40, Yes), the similar point calculation unit 13 ends the process according to the in 18 illustrated process. In this way, the similar point calculation unit 13 obtains the similar point 41 with the selection of the target trajectory 26 and the neighboring trajectory 27 for each cluster. The similar point calculation unit 13 calculates the similar point 41 for each command point 22 for each of a plurality of the tool paths 21 of each cluster.

19 is a flowchart illustrating a flow process in which the correction unit 14 of the machining program modification apparatus 11A according to the second embodiment creates the route 43 of similar points. In step S51, the correction unit 14 selects a plurality of the tool paths 21 of a target cluster by acquiring data on the plurality of tool paths 21 of the target cluster from the similar point calculating unit 13.

In step S52, the correction unit 14 selects the target path 26 from the plurality of tool paths 21 of the target cluster. In step S53, the correction unit 14 sets one of a plurality of the command points 22 on the target trajectory 26 as the target command point 40.

The correction unit 14 acquires data on the similar point 41 corresponding to the target command point 40 from the similar point calculation unit 13. In step S54, the correction unit 14 adds the similar point 41 for the target command point 40 to the similar point route 43.

In step S55, the correction unit 14 determines whether or not the similar point 41 added to the similar point route 43 is the command point 22 on the last tool path 21 in the target cluster. If the similar point 41 is not the command point 22 on the last tool path 21 of the target cluster (step S55, No), the correction unit 14 sets the similar point 41 as the next target command point 40 in step S56. The correction unit 14 executes a process according to the process of step S54 for the next target command point 40.

On the other hand, if the similar point 41 is the command point 22 on the last tool path 21 in the target cluster (step S55, Yes), the correction unit 14 determines whether or not the target command point 40 is the last command point 22 on the target path 26 in step S57. If the target command point 40 is not the last command point 22 on the target path 26 (step S57, No), the correction unit 14 sets the command point 22 next to the target command point 40 as a next target command point 40 in step S58. The correction unit 14 executes a process according to the process of step S54 for the next target command point 40.

On the other hand, if the target command point 40 is the last command point 22 on the target path 26 (step S57, Yes), the correction unit 14 determines whether or not the target path 26 is the last tool path 21 in the target cluster in step S59. If the target path 26 is not the last tool path 21 (step S59, No), the correction unit 14 selects the next target path 26 from the plurality of tool paths 21 of the target cluster in step S60. The correction unit 14 executes a process according to the process in step S53 for the next target trajectory 26.

On the other hand, if the target path 26 is the last tool path 21 in the target cluster (step S59, Yes), the correction unit 14 determines in step S61 whether the target cluster is a last cluster for the workpiece 10 is or not. If the target cluster is not the last cluster (step S61, No), the correction unit 14 selects a plurality of the tool paths 21 of the next target cluster in step S62 by receiving data on the plurality of tool paths 21 of the next target cluster from the unit 13 for calculating a similar point recorded. The correction unit 14 executes an operation according to the process of step S52 for the next target cluster.

On the other hand, if the target cluster is the last cluster for the workpiece 10 (step S61, Yes), the correction unit 14 finishes the process according to in 19 illustrated process. In this way, the correction unit 14 corrects the target trajectory 26 for each cluster.

According to the second embodiment, the machining program modification apparatus 11A classifies a group of tool paths for the workpiece 10 into a plurality of clusters based on the second feature amounts, and corrects the target path 26 for each cluster. The machining program modification device 11A can perform correction to reduce inconsistencies in shape between the tool paths 21 having their respective common features. As described above, the machining program modification device 11A has the advantageous effect of enabling improvement in the quality of the machined surface.

Third embodiment.

20 is a diagram illustrating a machining system 1B according to a third embodiment. The machining system 1B includes the CAM device 3, the machining program modification device 11, the numerical control device 5, and the machine tool 7. In the third embodiment, the same components as those in the above first or second embodiments are given the same reference numerals and a configuration different from that in the first or second embodiment will be mainly described.

The machining system 1B includes the machining program modification device 11 according to the first embodiment, and thus has the advantageous effect of enabling improvement in the quality of a machined surface. Note that the machining system 1B may be configured to include the machining program modification apparatus 11A according to the second embodiment.

The machining system 1B may be configured to implement a machining program modification method similar to that of the first or second embodiment by means of the CAM device 3 or the numerical control device 5 instead of a configuration with the machining program modification device 11 or 11A. In this case too, the machining system 1B can improve the quality of the machined area.

Next, hardware for implementing the machining program modification apparatus 11 according to the first embodiment or the machining program modification apparatus 11A according to the second embodiment will be described. 21 is a diagram showing an example of a hardware configuration for implementing the machining program modification apparatus 11 according to the first embodiment or the machining program modification apparatus 11A according to the second embodiment.

A main part of the machining program modification apparatus 11 or 11A is implemented by a processing circuit 61 having a processor 63 and a memory 64. The main part of the machining program modification device 11 is the first feature amount calculation unit 12, the similar point calculation unit 13, and the correction unit 14. The main part of the machining program modification device 11A is the second feature amount calculation unit 51 , the clustering unit 52, the unit 12 for calculating the first feature amount, the unit 13 for calculating a similar point and the correction unit 14.

An input unit 62 is a circuit that receives input signals from outside to the device 11 or 11A for modifying a machining program. The input unit 62 receives the machining program 4. An output unit 65 is a circuit that outputs signals generated by the machining program modification device 11 or 11A to the outside. The output unit 65 gives this modified machining program 15. A display unit 66 is a display that displays information.

The processor 63 is a central processing unit (CPU). The processor 63 may be an arithmetic device, a microprocessor, a microcomputer, or a digital signal processor (DSP). Memory 64 is non-volatile or volatile memory; Examples include random access memory (RAM), read only memory (ROM), flash memory, erasable programmable read only memory (EPROM), and electrically erasable programmable read only memory (EPROM). Erasable Programmable Read Only Memory, EEPROM (registered trademark).

The processor 63 executes a program for modifying a machining program. The machining program modification program is a program in which the processing for performing operations of units constituting the main part of the machining program modification apparatus 11 or 11A is described. The program for modifying a machining program is stored in memory 64 in advance. The processor 63 operates as each unit included in the main body of the machining program modification apparatus 11 or 11A by reading and executing the machining program modification program stored in the memory 64.

Although the program for modifying a machining program is described as previously stored in the memory 64, the present disclosure is not necessarily limited to this example. The machining program modification program may be provided to a user of the machining program modification device 11 or 11A in a state in which the program has been written into a storage medium configured to be read by a computer system installed by the user in memory 64. The storage medium may be a portable storage medium, which is a floppy disk, or a flash memory, which is a semiconductor memory. The program for modifying an editing program may be installed in memory 64 from another computer or server device via a communications network.

When the machine tool 7 is in the process of machining, the machining program modification device 11 or 11A corrects the tool path 21 on a real-time basis and generates the modified machining program 15. The machining program modification device 11 or 11A may be configured to: Tool path 21 corrected when not in the process of machining and may be configured to generate the modified machining program 15 when not in the process of machining. The machining program modification device 11 or 11A may be configured to test the machining performance by simulating the machining to be performed by the machine tool 7 based on the corrected tool path 21.

22 is a flowchart illustrating a flow process in which the machining program modification apparatus 11 according to the first embodiment or the machining program modification apparatus 11A according to the second embodiment executes simulation of machining. In step S71, the machining program modification device 11 or 11A generates a model of a machined product by simulating machining in the processor 63. In step S72, the machining program modification device 11 or 11A stores the generated model in the memory 64.

In step S73, the machining program modification device 11 or 11A generates an image of the machined product by rendering the model in the processor 63. In step S74, the machining program modification device 11 or 11A displays the image on the display unit 66. As described above, the machining program modification apparatus 11 or 11A completes the operation in accordance with FIG 22 illustrated process. The user can check the corrected tool path 21 by comparing the displayed image with the CAD model 2 before performing the actual machining.

The configuration described in each of the above embodiments shows an example of the contents of the present disclosure. The configuration of an embodiment may be combined with other publicly known techniques. The configurations of the embodiments can be suitably combined with each other. It is possible to share the configuration of each embodiment wise to omit or modify without departing from the scope of the present disclosure.

List of reference symbols

1.1B editing system; 2 CAD model; 3 CAM device; 4 editing program; 5 numerical control device; 6 control signal; 7 machine tool; 8 drive unit; 9 tool; 10 workpiece; 11, 11A Device for modifying a machining program; 12 Unit for calculating the first feature amount; 13 unit for calculating a similar point; 14 correction unit; 15 modified editing program; 20, 20A target shape; 21, 21-1, 21-2, 21-3, 21-4, 21-5, 21-6 tool path; 22, 22i, 22(i-1) command point; 23 starting point; 24i amount of movement; 25 endpoint; 26 target lane; 27 adjacent lanes; 31, 32, 33, 34, 35, 36, 56-1, 56-2, 56-3, 56-4, 56-5, 56-6 point; 40 Target Command Point; 41 similar point; 42 straight; 43 route of similar points; 44 smoothed route; 45 correction point; 46 level; 47 arrow line; 51 Unit for calculating the second feature amount; 52 clustering unit; 53 center of gravity position; 54 main component; 55 tool path length; 57-1, 57-2 region; 58-1 first cluster; 58-2 second cluster; 61 processing circuit; 62 input unit; 63 processor; 64 memories; 65 output unit; 66 display unit; PS, PS1, PS2 machined area.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 202067863 [0005]

Claims (10)

Device for modifying a machining program for modifying a machining program by correcting a tool path, which is a path on which a tool is moved by a machine tool, the machining program being configured to execute machining of the machine tool, the device for modifying a machining program comprising: a first feature amount calculating unit to obtain a first feature amount representing a feature of a command point on the tool path, the command point representing a position of the tool in a control period of the machine tool; a similar point calculating unit for selecting a target path to be corrected and a path adjacent to the target path from a plurality of the tool paths arranged in a direction other than a direction of movement on the tool path, and obtain a similar point from a plurality of command points on the adjacent trajectory based on the first feature amount of the command point on the target trajectory and the first feature amount of the command point on the adjacent trajectory, the similar point being a command point similar to the command point on the target trajectory; and a correction unit for correcting the target trajectory based on the similar point. Device for modifying a machining program Claim 1 , wherein the correction unit obtains the similar point for the command point on each of a plurality of the tool paths, thereby generating a similar point path connecting a plurality of the obtained similar points, and the target path by adjusting a position of the command point on the target path Corrected the basis of the route of similar points. Device for modifying a machining program Claim 2 , wherein the correction unit adjusts the position of the command point by smoothing the path of similar points and moving the command point on the target trajectory to the smoothed path of similar points. Device for modifying a machining program Claim 2 , wherein the correction unit obtains a plane passing through the successive command points on the target trajectory and adjusts the position of the command point on the plane. Device for modifying a machining program according to one of the Claims 1 until 4 , wherein the first feature amount includes at least one of information about coordinates of the command point, information about an amount of movement of the tool at the command point, and information about a length of the tool path to the command point. Device for modifying a machining program according to one of the Claims 1 until 5 , wherein the similar point calculating unit obtains the similar point by obtaining a mapping between the command point on the target trajectory and the command point on the adjacent trajectory, so that a distance error representing a difference between the first feature amount of the command point on the target trajectory and the first Feature amount of the command point on the adjacent path represents is minimal. Device for modifying a machining program according to one of the Claims 1 until 6 , further comprising: a unit for calculating the second feature amount to obtain a second feature amount representing a feature of the tool path; and a clustering unit for classifying a group of tool paths for machining a workpiece into a plurality of clusters based on the second feature amounts, wherein the similar point calculating unit obtains the similar point by selecting the target path and the adjacent path for each of the clusters , and the correction unit corrects the target trajectory for each of the clusters. Device for modifying a machining program Claim 7 , wherein the second feature amount includes at least one of information about coordinates of a center of gravity position of the tool path, information about a principal component that is an approximate straight line of a plurality of command points on the tool path, and information about a tool path length. A method of modifying a machining program, in which a machining program modification device modifies a machining program by correcting a tool path, which is a path on which a tool is moved with respect to a workpiece, the machining program being configured to use machining of the tool, the method of modifying a machining program comprising: a step of obtaining a first feature amount representing a feature of a command point on the tool path, the command point representing a position of the tool in a control period; a step of selecting a target path for which a correction is to be made and a path adjacent to the target path from a plurality of the tool paths arranged in a direction other than a direction of movement on the tool path; a step of obtaining a similar point from a plurality of command points on the adjacent trajectory based on the first feature amount of the command point on the target trajectory and the first feature amount of the command point on the adjacent trajectory, the similar point being a command point similar to the command point on the target trajectory ; and a step of correcting the target trajectory by correcting the command point on the target trajectory based on the similar point. Machining system, comprising: a device for creating a machining program for creating a machining program; the device for modifying a machining program according to one of the Claims 1 until 8th , which modifies the created editing program; and a numerical control device for controlling a device to be controlled based on the modified machining program.

Images