CN112470089B

CN112470089B - Tool path correction device, tool path correction method, and numerical control device

Info

Publication number: CN112470089B
Application number: CN201980048211.3A
Authority: CN
Inventors: 萨维尔拉马达尼; 金子弘树; 入口健二
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2018-07-24
Filing date: 2019-04-18
Publication date: 2024-05-03
Anticipated expiration: 2039-04-18
Also published as: DE112019003702T5; WO2020021793A1; CN112470089A; JPWO2020021793A1; JP6884283B2

Abstract

A tool path correction device (100) corrects tool path data representing a movement path of a tool relative to a processing object to be processed using the tool. The tool path data is data representing the position of the tool center and contains a command point associated with the tool pose at the position. A tool path correction device (100) is provided with: a correction target extraction unit (18) that extracts, from the tool path data, a command point that is determined to be a target of correction based on the amount of movement of the tool center and the amount of change in tool posture among the command points that are adjacent in the movement path; and a tool path data correction unit (21) that refers to machining shape data indicating a machining shape to be set as a target in machining of the object to be machined, and corrects the position and tool posture of the tool center at each command point included in the range defined by the command point extracted by the correction object extraction unit (18).

Description

Tool path correction device, tool path correction method, and numerical control device

Technical Field

The present invention relates to a tool path correction device, a tool path correction method, and a numerical control device for correcting tool path data for machining using a tool.

Background

The 5-axis control machine tool is a machine tool capable of performing 5-axis control machining, which can be realized by an operating mechanism capable of performing translational movement of each of the 3 axes and an operating mechanism capable of rotating about the 2 axes. The 5-axis control machining is used for machining a free-form surface or machining a shape that is difficult to machine by 3-axis control machining such as an impeller. The numerical control (Numerical Control:NC) device controls the 5-axis control machine tool according to tool path data created by a design operation using a Computer aided design (Computer AIDED DESIGN:CAD) and a Computer aided manufacturing (Computer Aided Manufacturing:CAM) device. The tool path data for 5-axis control machining includes a command for the tool posture, which is the posture of the tool with respect to the object to be machined.

Patent document 1 discloses an NC apparatus that can smoothly operate a tip position of a tool by smoothing an angular variation of a rotation axis in order to suppress a decrease in processing quality in a case where a change in tool posture or a change in a discontinuous variation is included in tool path data.

Patent document 1: japanese patent No. 4467625

Disclosure of Invention

However, in the prior art of patent document 1, the tip of the tool can be brought into contact with the object to be machined when using a ball nose end mill, and in the case of using a tool such as a round end mill or a flat end mill, the tip of the tool may be separated from the object to be machined or bitten into the object to be machined. The ball end mill is a tool with a spherical front end. The rounded end mill and the flat end mill are tools having a shape other than a sphere at the tip. Therefore, the conventional technique of patent document 1 has a problem that cutting remains due to separation of the tip of the tool from the object to be processed or excessive cutting due to biting of the tip of the tool into the object to be processed may occur, and the processing quality may be degraded.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a tool path correction device capable of suppressing degradation of machining quality.

In order to solve the above-described problems and achieve the object, a tool path correction device according to the present invention corrects tool path data indicating a movement path of a tool relative to a workpiece to be machined using the tool. The tool path data is data representing the position of the tool center and contains a command point associated with the tool pose at the position. The tool path correction device according to the present invention includes: a correction target extraction unit that extracts, from the tool path data, a command point that is determined to be a target of correction based on the amount of movement of the tool center and the amount of change in tool posture among the command points adjacent to each other in the movement path; and a tool path data correction unit that corrects the position and tool posture of the tool center at each command point included in the range defined by the command point extracted by the correction object extraction unit, with reference to machining shape data indicating a machining shape set as a target in machining the object.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, the tool path correction device has an effect of being able to suppress degradation of the machining quality.

Drawings

Fig. 1 is a block diagram showing a functional configuration of a tool path correction device according to embodiment 1 of the present invention.

Fig. 2 is a block diagram showing a hardware configuration of the tool path correction device according to embodiment 1.

Fig. 3 is a flowchart showing a sequence of operations performed by the tool path correction device shown in fig. 1.

Fig. 4 is a diagram illustrating tool data input to the tool path correction device shown in fig. 1.

Fig. 5 is a diagram illustrating tool path data input to the tool path correction device shown in fig. 1.

Fig. 6 is a diagram illustrating machining shape data input to the tool path correction device shown in fig. 1.

Fig. 7 is a flowchart showing a procedure of operations performed by the correction target extracting unit included in the tool path correction device shown in fig. 1.

Fig. 8 is a diagram illustrating an operation performed by the correction target extracting unit included in the tool path correction device shown in fig. 1.

Fig. 9 is a diagram illustrating an operation performed by the correction range defining unit included in the tool path correction device shown in fig. 1.

Fig. 10 is a flowchart showing a sequence of operations for correcting tool path data by the tool path correction device shown in fig. 1.

Fig. 11 is a flowchart showing an operation sequence in the case where the tool path data correction unit included in the tool path correction device shown in fig. 1 corrects the tool axis vector by the 1 st method.

Fig. 12 is a diagram illustrating correction of the tool axis vector by the sequence shown in fig. 11.

Fig. 13 is a flowchart showing an operation sequence in the case where the tool path data correction unit included in the tool path correction device shown in fig. 1 corrects the tool axis vector by the method 2.

Fig. 14 is a view 1 illustrating correction of a tool axis vector by the sequence shown in fig. 13.

Fig. 15 is a view 2 illustrating correction of a tool axis vector by the sequence shown in fig. 13.

Fig. 16 is a diagram showing an example of the positional relationship between the machining curved surface and the tool in the sequence from step S24 to step S26 in the sequence shown in fig. 10.

Fig. 17 is a diagram showing an example of the positional relationship between the machining curved surface and the tool in the sequence of step S27 in the sequence shown in fig. 10.

Fig. 18 is a diagram showing an example of the positional relationship between the machining curved surface and the tool in the sequence of step S28 in the sequence shown in fig. 10.

Fig. 19 is a block diagram showing a functional configuration of an NC apparatus according to embodiment 2 of the present invention.

Fig. 20 is a flowchart showing a sequence of operations performed by the NC apparatus shown in fig. 19.

Detailed Description

The tool path correction device, the tool path correction method, and the numerical control device according to the embodiment of the present invention will be described in detail below with reference to the drawings. The present invention is not limited to the present embodiment.

Embodiment 1.

Fig. 1 is a block diagram showing a functional configuration of a tool path correction device 100 according to embodiment 1 of the present invention. The tool path correction device 100 corrects tool path data for machining using a tool. In embodiment 1, the tool path data is set to be tool path data for cutting machining using a cutting tool.

The tool path correction device 100 includes: a tool path data input unit 10 which is a functional unit for inputting tool path data from the outside of the tool path correction device 100; and a tool path data storage unit 11 that is a functional unit for storing tool path data input to the tool path data input unit 10. The tool path data is data indicating a movement path of the tool relative to the object to be machined by using the tool. The tool path data is data that represents a position of the tool center and contains a command point associated with a tool posture at the position. The tool center and the tool posture are described later.

The tool path correction device 100 includes: a machining shape data input unit 12 that is a functional unit for inputting machining shape data from outside the tool path correction device 100; and a machining shape data storage unit 13 that is a functional unit for storing machining shape data input to the machining shape data input unit 12. The processing shape data is data indicating a processing shape to be a target in processing the object to be processed. An example of the machined shape data is CAD data.

The tool path correction device 100 includes: a tool data input unit 14 that is a functional unit for inputting tool data from outside the tool path correction device 100; and a tool data storage unit 15 that is a functional unit for storing tool data input to the tool data input unit 14. The tool data is information defining a tool used for machining a machining object. The tool data includes information indicating the type of the tool, and information indicating the shape of the tool, such as the tool radius, the tool edge radius, and the tool length.

The tool path correction device 100 includes: a setting input unit 16 which is a functional unit for inputting configuration data from the outside of the tool path correction device 100; and a setting storage unit 17 that is a functional unit for storing the configuration data input to the setting input unit 16. The configuration data is various setting data concerning the processing of the tool path correction device 100. The configuration data includes the following data: data indicating settings in the determination by the correction target extraction unit 18 described later and data indicating settings in the definition of the range by the correction range definition unit 19 described later. The setting items that can input the configuration data to the setting input unit 16 are items that can be specified and changed by the user of the tool path correction device 100.

The tool path correction device 100 includes: a correction target extraction unit 18 that extracts, from the tool path data, a command point that is determined to be a target of correction, from among the adjacent command points in the movement path, based on the amount of movement of the tool center and the amount of change in tool posture; and a correction range demarcating unit 19 demarcating a range of command points including the command points extracted by the correction target extracting unit 18. The tool path correction device 100 includes a correction target range storage unit 20, and the correction target range storage unit 20 is a functional unit that stores information of the command point extracted by the correction target extraction unit 18 and information of the range defined by the correction range defining unit 19.

The correction target extracting unit 18 reads the tool path data from the tool path data storage unit 11 and reads the arrangement data from the setting storage unit 17. The correction target extracting unit 18 outputs the information of the extracted command point to the correction range delimiting unit 19. The correction range demarcation unit 19 reads the tool path data from the tool path data storage unit 11 and reads the arrangement data from the setting storage unit 17.

The tool path correction device 100 includes: a tool path data correction unit 21 for correcting the position and tool posture of the tool center at each command point within the range defined by the correction range definition unit 19 in the tool path data, with reference to the machining shape data; and a corrected tool path data storage unit 22 that is a functional unit for storing the tool path data corrected by the tool path data correction unit 21.

The tool path data correction unit 21 reads the machining shape data from the machining shape data storage unit 13 and reads the tool data from the tool data storage unit 15. The tool path data correction unit 21 reads out, from the correction target range storage unit 20, information of the command point extracted by the correction target extraction unit 18 and information of the range defined by the correction range definition unit 19. The tool path data correction unit 21 reads the tool path data from the tool path data storage unit 11, and corrects the read tool path data.

Here, a hardware configuration of the tool path correction device 100 will be described. Each functional unit of the tool path correction device 100 shown in fig. 1 is realized by executing a tool path correction program for executing the tool path correction method according to embodiment 1 by hardware.

Fig. 2 is a block diagram showing a hardware configuration of the tool path correction device 100 according to embodiment 1. The tool path correction device 100 includes: CPU (Central Processing Unit) 31, which perform various processes; RAM (Random Access Memory) 32, which contains a data storage area; ROM (Read Only Memory) 33, which is a non-volatile memory; an external storage device 34; and an input-output interface 35 for inputting information to the tool path correction device 100 and outputting information from the tool path correction device 100. The respective parts of the tool path correction device 100 shown in fig. 2 are connected to each other via a bus 36.

The CPU 31 executes programs stored in the ROM 33 and the external storage device 34. The functions of the correction target extracting unit 18, the correction range delimiting unit 19, and the tool path data correcting unit 21 shown in fig. 1 are realized by using the CPU 31. The external storage device 34 is HDD (Hard Disk Drive) or SSD (Solid STATE DRIVE). The external storage device 34 stores a tool path correction program and various data. The functions of the tool path data storage unit 11, the machining shape data storage unit 13, the tool data storage unit 15, the setting storage unit 17, the correction target range storage unit 20, and the corrected tool path data storage unit 22 shown in fig. 1 are realized by using the external storage device 34. The ROM 33 stores software or a program for controlling hardware, such as a boot loader, i.e., a BIOS (Basic Input/Output System) or UEFI (Unified Extensible FIRMWARE INTERFACE), which is a program for controlling a computer or a controller of the tool path correction device 100. The tool path correction program may be stored in the ROM 33.

Programs stored in the ROM 33 and the external storage device 34 are loaded into the RAM 32. The CPU 31 expands the tool path correction program in the RAM 32 to execute various processes. The input/output interface 35 is a connection interface with an external device of the tool path correction device 100. The functions of the tool path data input unit 10, the machined shape data input unit 12, the tool data input unit 14, and the setting input unit 16 shown in fig. 1 are realized by using the input/output interface 35. The tool path correction device 100 may have an input device such as a keyboard and a pointing device, and an output device such as a display.

The tool path correction program may be stored in a computer-readable storage medium. The tool path correction device 100 may store the tool path correction program stored in the storage medium in the external storage device 34. The storage medium may be a floppy disk, i.e., a removable storage medium, or a semiconductor memory, i.e., a flash memory. The tool path correction program may be installed from another computer or a server apparatus to a computer serving as the tool path correction apparatus 100 via a communication network.

The function of the tool path correction device 100 can be realized by a processing circuit, which is dedicated hardware for correcting a tool path. The processing circuitry is a single Circuit, a composite Circuit, a programmed processor, a parallel programmed processor, an ASIC (Application SPECIFIC INTEGRATED Circuit), an FPGA (Field-Programmable GATE ARRAY), or a combination thereof. The functions of the tool path correction device 100 may be implemented in one part by dedicated hardware and in another part by software or firmware.

Next, the operation performed by the tool path correction device 100 will be described. Fig. 3 is a flowchart showing a sequence of operations performed by the tool path correction device 100 shown in fig. 1. Step S1 is a step in which the tool path correction device 100 imports tool path data, machining shape data, tool data, and configuration data.

In step S1, the tool path data input unit 10 shown in fig. 1 inputs tool path data from outside the tool path correction device 100. The machined shape data input unit 12 shown in fig. 1 inputs machined shape data from outside the tool path correction device 100. The tool data input unit 14 shown in fig. 1 inputs tool data from outside the tool path correction device 100. The setting input unit 16 shown in fig. 1 inputs configuration data from outside the tool path correction device 100. Each data is input to each input unit from an external device connected to the tool path correction device 100. The data may be entered by manual input by a user. The tool path correction device 100 can acquire tool path data by data conversion of the NC program.

The tool path data storage unit 11 shown in fig. 1 stores the tool path data input to the tool path data input unit 10 in step S1. The machined shape data storage unit 13 shown in fig. 1 stores machined shape data input to the machined shape data input unit 12 in step S1. The tool data storage unit 15 shown in fig. 1 stores the tool data input to the tool data input unit 14 in step S1. The setting storage unit 17 shown in fig. 1 stores the configuration data input to the setting input unit 16 in step S1.

Step S2 is a step in which the correction target extracting unit 18 extracts the command point determined to be the target of correction from the tool path data. In step S2, the correction target extracting unit 18 reads out the tool path data stored in the tool path data storage unit 11. The correction target extraction unit 18 determines whether or not the correction target is the target of correction for each command point described in the read tool path data, and extracts the command point determined to be the target of correction. The correction target range storage unit 20 stores the instruction point extracted in step S2. The correction target extracting unit 18 outputs the information of the extracted command point to the correction range delimiting unit 19.

Step S3 is a step in which the correction range delimiting unit 19 delimits the ranges of the plurality of command points to be corrected. In step S3, the correction range delimiting unit 19 reads out the tool path data stored in the tool path data storage unit 11. The correction range demarcation unit 19 demarcates a range of a plurality of command points including the command point extracted by the correction target extraction unit 18, based on the information of the command point output from the correction target extraction unit 18 among the read tool path data. Thus, the correction range demarcation unit 19 demarcates the ranges of the plurality of command points to be corrected. The correction target range storage unit 20 stores a correction target range, which is a range set as a target of correction, defined in step S3.

Step S4 is a step in which the tool path data correction unit 21 corrects the position and tool posture of the tool center. In step S4, the tool path data correction unit 21 reads out the machining shape data stored in the machining shape data storage unit 13, the tool data stored in the tool data storage unit 15, and the correction target information stored in the correction target range storage unit 20. The tool path data correction unit 21 refers to the read processing shape data and tool data, and corrects the position and tool posture of the tool center of the command point in the correction target range defined in step S3 in the tool path data. The corrected tool path data storage unit 22 stores the corrected tool path data in step S4. Thereby, the tool path correction device 100 ends the operations performed in the sequence shown in fig. 3. Further, details of steps S2 to S4 are described later.

Next, tool data, tool path data, and machining shape data will be described. Fig. 4 is a diagram illustrating tool data input to the tool path correction device 100 shown in fig. 1. An example of the shape of the tool TL represented by the tool data is shown in fig. 4. Here, the tool TL is provided as a corner end mill. The end of the tool TL toward the object side is sometimes referred to as a tip end, and the end of the tool TL opposite to the tip end and attached to the machine side is sometimes referred to as a root.

The tool TL is shaped to chamfer the edges in the bottom of the cylinder. The tool tip radius R2 is the radius of the chamfer. The tool radius R1 is the radius of the cylinder. The tip portion of the cutter TL has a bottom TB formed in a circular shape. The value of the tool radius R1 and the value of the tool tip radius R2 are included in the tool data and indicate the shape of the tool TL. The tool center axis TX is a center axis of a cylinder and is an axis that becomes a rotation center of the tool TL at the time of machining. The center of the bottom TB and the tool center CL are on the tool center axis TX. The tool center CL is located at a position on the root side of the bottom TB by an amount corresponding to the length of the tool edge radius R2. The tool axis vector TV is a vector parallel to the tool center axis TX and directed from the tool center CL toward the root side. The tool pose is represented by a tool axis vector TV.

Fig. 5 is a diagram illustrating tool path data input to the tool path correction device 100 shown in fig. 1. The X-axis, Y-axis and Z-axis are set to 3-axis of a coordinate system representing tool path data. The position of the tool indicated by the tool path data is a position when the tool is used to process the object, and indicates a relative position of the tool with respect to the object. The position of the tool center CL and the direction of the tool axis vector TV are indicated by the coordinates X, Y and Z. Fig. 5 shows the tool center CL and the tool axis vector TV after projection onto a plane parallel to the X-axis and the Z-axis.

The command point CP represents the position of the tool center CL and represents a command associated with the tool axis vector TV at that position. The tool path data is data indicating a movement path TP of the tool, and is constituted by a plurality of command points CP connected to each other. The coordinates indicating the position of the tool center CL among the command points CP indicate positions on the movement path TP when the tool is moved in a virtual space indicated by the coordinate system of the tool path data. In the following description, the command point CP may be a position of the tool center CL when the tool is moved according to the tool path data. Fig. 5 shows a plurality of command points CP connected to each other in the tool path data.

Fig. 6 is a diagram illustrating machining shape data input to the tool path correction device 100 shown in fig. 1. Fig. 6 shows an example of a machined shape CT represented by machined shape data. The machined shape CT illustrated in fig. 6 includes a free-form surface, i.e., a machined curved surface CS. The tool path data for machining the machining curved surface CS is created by bringing the tip portion of the tool TL shown in fig. 4 into contact with the machining curved surface CS to approximate a path in which the tool TL is virtually moved to a straight line or a curved line, that is, a differential line segment. The tool path data correction unit 21 matches the coordinate system of the machining shape data with the coordinate system of the tool path data.

Fig. 7 is a flowchart showing a sequence of operations performed by the correction target extraction unit 18 included in the tool path correction device 100 shown in fig. 1. Fig. 7 shows a sequence of operations performed by the correction object extracting unit 18 for extracting the instruction point determined to be the object of correction. The sequence shown in fig. 7 shows details of the sequence in step S2 shown in fig. 3.

In step S11, the correction target extracting unit 18 reads out the tool path data stored in the tool path data storage unit 11. In step S12, the correction target extraction unit 18 calculates the amount of movement of the position of the tool center CL in 2 command points CP adjacent to each other in the movement path TP, from among the tool path data read out in step S11.

Fig. 8 is a diagram illustrating an operation performed by the correction target extracting unit 18 included in the tool path correction device 100 shown in fig. 1. Fig. 8 shows 10 command points CP connected in the tool path data. The instruction point CP5 is the 5 th instruction point CP among 10 instruction points CP shown in fig. 8. The instruction point CP6 is the 6 th instruction point CP among 10 instruction points CP shown in fig. 8. The instruction point CP5 and the instruction point CP6 are 2 instruction points adjacent to each other in the moving path TP.

If the example is shown, the correction target extracting unit 18 calculates the movement amount D5 of the tool center CL in the movement path TP between the command point CP5 and the command point CP6 with respect to the command point CP5 and the command point CP 6. The movement amount D5 is a distance between the coordinates of the tool center CL5 indicated by the command point CP5 and the coordinates of the tool center CL6 indicated by the command point CP 6.

In step S13, the correction target extracting unit 18 calculates the angle change amount of the tool axis vector TV at 2 command points CP adjacent to each other in the moving path TP, from among the tool path data read out in step S11. The angle change amount of the tool axis vector TV is the change amount of the tool posture.

If the example is shown, the correction target extracting unit 18 calculates the angle change amount AC5 from the direction of the tool axis vector TV5 at the command point CP5 to the direction of the tool axis vector TV6 at the command point CP6 with respect to the command points CP5 and CP 6.

Step S14 is a step in which the correction target extracting unit 18 determines whether or not the 2 instruction points CP are targets of correction. In step S14, the correction target extracting unit 18 calculates a ratio of the amount of angular change to the amount of movement of the tool center CL with respect to 2 command points, and determines whether the calculated ratio is equal to or greater than a threshold value. When the calculated ratio is greater than or equal to the threshold value, the correction target extraction unit 18 determines that 2 instruction points are targets of correction. When the calculated ratio is smaller than the threshold value, the correction target extraction unit 18 determines that the 2 instruction points are not targets for correction.

If this is the case, for example, the correction target extraction unit 18 calculates the ratio AC5/D5 of the angular change amount AC5 to the movement amount D5 with respect to the command points CP5 and CP 6. When the calculated ratio AC5/D5 is equal to or greater than the threshold value, the correction target extraction unit 18 determines the portion EP5, which is a combination of the command point CP5 and the command point CP6 in the movement path TP, as a target of correction. When the calculated ratio AC5/D5 is smaller than the threshold value, the correction target extraction unit 18 determines that the portion EP5 is not the target of correction.

When the ratio is greater than or equal to the threshold (Yes in step S14) and it is determined that 2 command points are the object of correction, the correction object extraction unit 18 extracts the 2 command points from the tool path data in step S15. The correction target range storage unit 20 stores the instruction point extracted in step S15. The correction target extracting unit 18 outputs the information of the extracted command point to the correction range delimiting unit 19. After the extraction of the 2 instruction points, the correction target extraction unit 18 advances the operation sequence to step S16. On the other hand, when the ratio is smaller than the threshold (step S14, no) and it is determined that 2 instruction points are not the target of correction, the correction target extraction unit 18 also advances the sequence of operations to step S16.

In step S16, the correction target extraction unit 18 determines whether or not the determination of whether or not the correction target is completed with respect to all combinations of 2 adjacent command points in the tool path data. If it is determined that the correction is not completed (No in step S16), the correction target extraction unit 18 performs the operations performed in the order of steps S12 to S16 with respect to the next combination of 2 instruction points. When the determination is completed (Yes in step S16), the correction target extraction unit 18 ends the operation for extracting the command point.

The threshold value is included in the data representing the setting in the determination by the correction target extraction unit 18, among the arrangement data stored in the setting storage unit 17. The correction target extraction unit 18 obtains a threshold value from the configuration data, and performs the determination in step S14. The threshold value is included in the configuration data, and thus can be arbitrarily set by the user. Thus, the tool path correction device 100 can reflect the user's request to correct the tool path data.

The threshold value used in the determination in step S14 is not limited to being set by the configuration data. The threshold value may be determined by calculation in the correction target extraction unit 18. The correction target extraction unit 18 may calculate an average value of the angle change amounts based on the data of the angle change amounts, and may set a value obtained by multiplying the standard deviation about the average value by 2 as a threshold value. The correction target extraction unit 18 may calculate the 3 rd quartile of the angle change amount based on the data of the angle change amount, and may set a value obtained by adding a value 1.5 times the quartile range to the 3 rd quartile as the threshold value. The method described above for determining the threshold value applies the theory of deviation value detection in statistics. The method for obtaining the threshold value is not limited to the above method, but is arbitrary.

Next, an operation for defining the correction target range by the correction range defining unit 19 will be described. Fig. 9 is a diagram illustrating an operation performed by the correction range defining unit 19 included in the tool path correction device 100 shown in fig. 1. Fig. 9 shows an operation of the correction range demarcation unit 19 for demarcating the correction target range.

The correction range demarcation unit 19 reads out the tool path data stored in the tool path data storage unit 11. The correction range delimiting unit 19 obtains information of the instruction point extracted by the correction target extracting unit 18 from the correction target extracting unit 18. The correction range demarcation unit 19 includes the command point extracted by the correction target extraction unit 18, 1 or more command points before the extracted command point in the movement path TP, and 1 or more command points after the extracted command point in the movement path TP in the correction target range.

If, for example, the correction range delimiting unit 19 obtains information of the instruction points CP5 and CP6 extracted by the correction target extracting unit 18 from the correction target extracting unit 18. The number of instruction points included in the correction target range is 4 in the range before the extracted instruction point and 4 in the range after the extracted instruction point, and is set in the configuration data. The correction range delimiting unit 19 includes, in addition to the command points CP5 and CP6, the command points CP1, CP2, CP3, and CP4, which are 4 command points in the range RB before the command point CP5, and the command points CP7, CP8, CP9, and CP10, which are 4 command points in the range RF after the command point CP 6. Thus, the correction range delimiting unit 19 delimits the range RG formed by 10 command points from the command point CP1 to the command point CP10 as the correction target range. The correction target range storage unit 20 stores the correction target range defined by the correction range defining unit 19.

The data representing the setting in the range definition by the correction range definition unit 19, among the arrangement data stored in the setting storage unit 17, includes information of the number of instruction points included in the range of the instruction point to be corrected. The correction range demarcation unit 19 obtains the number of pieces of information from the arrangement data and demarcates the range. This number of pieces of information is included in the configuration data, whereby the number of instruction points included in the range can be arbitrarily set by the user. Thus, the tool path correction device 100 can reflect the user's request to correct the tool path data.

The number of instruction points included in the correction target range is not limited to the setting by the configuration data. The number of instruction points included in the correction target range may be determined by calculation in the correction range defining unit 19. The correction range delimiting unit 19 may set a 5% equivalent amount of the number of command points in the 1-cycle path as the number of command points included in the correction target range. When machining a region from 1 end to another 1 end in the contour of the machining shape by moving or reciprocally moving the tool in one direction, 1 cycle path means a movement path of 1 movement amount from 1 end to another 1 end in the movement path TP. The 5% equivalent is based on the theory of statistically significant difference testing. The number of instruction points included in the range may be greater than or equal to 5% of the number of instruction points in the 1-cycle path, or may be 10% of the number of instruction points. The method for determining the number of instruction points included in the correction target range is not limited to the above method, but is arbitrary.

Fig. 10 is a flowchart showing a sequence of operations for correcting tool path data by the tool path correction device 100 shown in fig. 1. The sequence shown in fig. 10 shows details of the sequence in step S4 shown in fig. 3.

In step S21, the tool path data correction unit 21 reads out the information of the correction target range from the correction target range storage unit 20. In step S22, the tool path data correction unit 21 reads out the machining shape data stored in the machining shape data storage unit 13. In step S23, the tool path data correction unit 21 reads out the tool data stored in the tool data storage unit 15. The order of steps S21 to S23 is not limited to the order shown in fig. 10, but is arbitrary.

In step S24, the tool path data correction unit 21 simulates the arrangement of the machining shape CT and the tool TL for each command point within the correction target range read out in step S21. The tool path data correction unit 21 performs calculation by arranging the machining shape CT represented by the machining shape data read out in step S22 and the tool TL represented by the tool data read out in step S23 in a virtual space in a simulated manner, thereby simulating the arrangement of the machining shape CT and the tool TL.

In step S25, the tool path data correction unit 21 calculates the position of the contact point, which is the point where the machined shape CT matches the contour of the tool TL, for each command point within the correction target range. The position of the contact point is the position of a machining point in the machining curved surface CS at which machining is performed by the tool TL.

In step S26, the tool path data correction unit 21 calculates the position of the tool reference point for each command point in the correction target range. The tool reference point is a position on the tool center axis TX at the root of the tool TL, and a position gripped by the work machine among the tools TL. The tool posture is changed by the rotation motion of the tool TL centered on the tool reference point. The tool reference point is also a position that becomes a reference in the change of the tool posture.

In step S27, the tool path data correction unit 21 corrects the tool axis vector TV for each command point in the correction target range. In step S28, the tool path data correction unit 21 corrects the position of the tool center CL for each command point in the correction target range. Thereby, the tool path data correction unit 21 ends the operation for correcting the tool path data.

Next, the correction of the tool axis vector TV in step S27 will be described. The tool path data correction unit 21 corrects the tool axis vector TV by the 1 st method related to the filtering process or the 2 nd method related to the generation of the approximate curve.

Fig. 11 is a flowchart showing an operation sequence in the case where the tool path data correction unit 21 included in the tool path correction device 100 shown in fig. 1 corrects the tool axis vector TV by the 1 st method. In step S31, the tool path data correction unit 21 performs correction by smoothing coordinates indicating the position of the tool reference point calculated in step S26. The tool path data correction unit 21 corrects the position of the tool reference point by applying a filter process to coordinates indicating the position of the tool reference point in the command point in the correction target range.

The tool path data correction unit 21 uses a smoothing filter to smooth coordinates indicating the position of the tool reference point. A known triangular smoothing (triangular smoothing) filter can be used as the smoothing filter. The smoothing filter smoothes coordinates representing the position of the tool reference point with respect to a central command point, i.e., a target command point, among the 5 command points, using coordinates of 5 consecutive command points in the movement path TP.

The smoothing filter calculates smoothed coordinates P' _n for the target point based on the following equation (1) using coordinates P _n－2、P_n－1、P_n、P_n+1、P_n+2 of the tool reference points for the 5 target points. The coordinates P _n are set as coordinates of the tool reference point related to the target instruction point. The coordinates P _n－2、P_n－1 are set as coordinates of tool reference points related to 2 previous command points and 1 previous command point of the target command point, respectively. The coordinates P _n+1、P_n+2 are set as coordinates of tool reference points related to the command points 1 and 2 after the command point of interest, respectively. The smoothing filter performs smoothing on the X-coordinate, the Y-coordinate, and the Z-coordinate based on the formula (1), respectively.

P’_n＝(P_n－2+2P_n－1+3P_n+2P_n+1+P_n+2)/9···(1)

The smoothing based on the formula (1) is performed for 4 instruction points other than 2 instruction points located at both ends of the correction target range and 2 instruction points adjacent to the instruction points, among the instruction points within the correction target range. When the correction target range is the range RG including the command points CP1 to CP10 according to the above example, smoothing based on the expression (1) is performed for 6 command points, i.e., the command points CP3 to CP 8.

Smoothing is not performed for 2 instruction points located at both ends of the correction target range. Regarding the instruction point located adjacent to the instruction point located at the front end among the correction target ranges, the smoothing filter calculates the coordinates P' _n based on the following expression (2). Regarding the instruction point located adjacent to the instruction point located at the rear side end among the correction target range, the smoothing filter calculates the coordinate P' _n based on the following expression (3). In the case of the above example, smoothing based on the expression (2) is performed with respect to the instruction point CP 2. Further, smoothing based on equation (3) is performed with respect to the instruction point CP 9.

P’_n＝(2P_n－1+3P_n+2P_n+1+P_n+2)/8···(2)

P’_n＝(P_n－2+2P_n－1+3P_n+2P_n+1)/8···(3)

The smoothing is not limited to the above-described formulas (1) to (3). The content calculated by the smoothing filter is arbitrary. In addition to the triangular smoothing filter described above, a Savitzky-Golay filter or a gaussian filter may be used as the smoothing filter.

In step S32, the tool path data correction unit 21 corrects the tool axis vector TV in a direction from the tool center CL toward the smoothed tool reference point in step S31 for each command point in the correction target range. Thereby, the tool path data correction unit 21 ends the operation for correcting the tool axis vector TV.

Fig. 12 is a diagram illustrating correction of the tool axis vector TV by the sequence shown in fig. 11. Fig. 12 shows 10 command points CP connected in the tool path data. The dashed arrow indicates the tool axis vector TV before correction. The solid arrow indicates the corrected tool axis vector TV'.

If, for example, the command point CP6 is a target command point, the tool path data correction unit 21 uses the coordinates of the tool reference points concerning the 5 command points CP4, CP5, CP6, CP7, and CP8 to smooth the command point CP6 from the tool reference point P to the tool reference point P'. The tool path data correction unit 21 corrects the tool axis vector TV in the direction from the tool center CL toward the tool reference point P to the tool axis vector TV 'in the direction from the tool center CL toward the smoothed tool reference point P'.

Fig. 13 is a flowchart showing an operation sequence in the case where the tool path data correction unit 21 included in the tool path correction device 100 shown in fig. 1 corrects the tool axis vector TV by the 2 nd method. In step S41, the tool path data correction unit 21 generates an approximation curve of the tool reference point for each command point of the correction target range.

The tool path data correction unit 21 generates an approximation curve based on the coordinates of the tool reference point calculated in step S26 and the movement amounts of the tool reference points out of the 2 adjacent command points. For example, the tool path data correction unit 21 generates a polynomial curve of degree 3, which is an approximation curve, by the least square method.

Fig. 14 is a view 1 illustrating correction of the tool axis vector TV by the sequence shown in fig. 13. Fig. 14 shows 10 command points CP connected in the tool path data. The movement amount DP is a distance between coordinates of the tool reference point P among the adjacent 2 command points CP. In step S41, the tool path data correction unit 21 obtains a parameter for generating the approximation curve SC for each tool reference point P using the ratio of the movement amount DP between each tool reference point P to the total value of the movement amounts DP in the correction target range. The parameter related to the tool reference point P located at the front end in the correction target range is set to zero. The parameter related to the tool reference point P located at the rear end in the correction target range is set to 1.

The tool path data correction unit 21 obtains parameters indicating the coordinates of each of X, Y and Z based on the coordinates of each tool reference point P and the obtained parameters. The tool path data correction unit 21 generates an approximation curve SC, that is, a polynomial curve of degree 3, based on the parameter values and the above parameters.

In step S42 shown in fig. 13, the tool path data correction unit 21 calculates the amount of movement of the position of the tool center among the 2 adjacent command points. In step S43, the tool path data correction unit 21 smoothes the coordinates representing the position of the tool reference point.

Fig. 15 is a diagram of fig. 2 for explaining the correction of the tool axis vector TV by the sequence shown in fig. 13. In step S43, the tool path data correction unit 21 calculates a ratio of the movement amount D of the tool center CL at each command point CP to the total value of the movement amounts D in the correction target range. The tool path data correction unit 21 corrects the parameter related to the tool reference point P so as to match the ratio of the movement amount D, thereby converting the parameter to a new parameter T. The parameter T related to the tool reference point P located at the front end in the correction target range is set to zero. The parameter T related to the tool reference point P located at the rear end in the correction target range is set to 1. Thus, the position of the tool reference point P located at the end of the correction target range is not changed.

The tool path data correction unit 21 calculates the coordinates of the smoothed tool reference point P' by adjusting the interval of the tool reference point P on the approximation curve SC of the correction target range so that the ratio of the movement amounts DP becomes a ratio according to the new parameter T. In the above manner, the tool path data correction unit 21 corrects the tool reference point P to the tool reference point P' based on the ratio of the generated approximation curve SC and the movement amount D. The approximation curve SC may be a Non-uniform rational B-spline (NURBS) curve, a spline curve, or a bezier curve, in addition to the 3-degree polynomial curve described above.

In step S44 shown in fig. 13, the tool path data correction unit 21 corrects the tool axis vector in a direction from the tool center toward the smoothed tool reference point. As shown in fig. 15, the tool path data correction unit 21 corrects the tool axis vector TV in the direction from the tool center CL toward the tool reference point P to the tool axis vector TV 'in the direction from the tool center CL toward the smoothed tool reference point P'.

Next, before the explanation concerning step S28 shown in fig. 10, the state of the tool TL in the virtual space in the sequence up to step S27 will be explained.

Fig. 16 is a diagram showing an example of the positional relationship between the machining curved surface CS and the tool TL in the sequence from step S24 to step S26 in the sequence shown in fig. 10. Fig. 16 shows a machining curve CS and a tool TL which are arranged in a simulated manner in a virtual space. The tool TL is disposed at each command point CP within the correction target range. The tool path data correction unit 21 verifies the positional relationship between the tool TL and the machining curved surface CS at each command point CP within the correction target range RG by the simulation in step S24. The portion EP shown in fig. 16 is a portion EP5 shown in fig. 8, and shows command points CP5 and CP6 extracted by the correction target extracting unit 18.

The contact point CC in the tool TL disposed at each command point CP within the correction target range RG is a point at which the machining shape CT matches the contour of the tool TL. In step S25 described above, the tool path data correction unit 21 calculates coordinates indicating the position of the contact point CC based on the result of verifying the positional relationship between the machining curved surface CS and the tool TL. In step S26 described above, the tool path data correction unit 21 calculates coordinates indicating the position of the tool reference point P in the tool TL disposed at each command point CP within the correction target range RG.

Fig. 17 is a diagram showing an example of the positional relationship between the machining curved surface CS and the tool TL in the sequence of step S27 in the sequence shown in fig. 10. In step S27 described above, the tool path data correction unit 21 corrects the tool axis vector TV for each command point CP. Fig. 17 shows the corrected tool axis vector TV'. The tool TL at each command point CP keeps the position of the tool center CL constant, and changes the direction of the tool center axis TX from the direction of the tool axis vector TV before correction to the direction of the tool axis vector TV' after correction.

As described above, the inclination of the tool TL changes without changing the position of the tool center CL, and thus, the contact between the machining curved surface CS and the contour of the tool TL can be changed. In the tool TL at each command point CP, there may be a portion where the contour of the tool TL is separated from the machining curved surface CS and a portion where the contour of the tool TL enters the inside of the object from the machining curved surface CS. The portion UC shown in fig. 17 is an example of a portion where the contour of the tool TL is separated from the machining curved surface CS. The portion OC shown in fig. 17 is an example of a portion where the contour of the tool TL enters the inside of the object from the machining curved surface CS.

Next, correction of the position of the tool center CL in step S28 will be described. Fig. 18 is a diagram showing an example of the positional relationship between the machining curved surface CS and the tool TL in the sequence of step S28 in the sequence shown in fig. 10. The tool path data correction unit 21 corrects the position of the tool center CL in step S28 so as to adjust the contour of the tool TL to match the contact point CC calculated in step S25.

The tool path data correction unit 21 calculates a deviation due to a change in the direction of the tool axis vector TV and a deviation of the contour of the tool TL from the contact point CC on the machining curved surface CS by verifying the positional relationship between the machining curved surface CS and the tool TL. The tool path data correction unit 21 obtains the movement direction and the movement amount of the position of the tool center CL that can cancel the offset between the contact point CC and the tool TL. The tool path data correction unit 21 corrects the position of the tool center CL in accordance with the calculated movement direction and movement amount, thereby matching the contour of the tool TL with the contact point CC. As described above, the tool path data correction unit 21 corrects the position of the tool center CL based on the result of calculating the deviation of the contour of the tool TL from the contact point CC, which is generated by the correction of the tool posture.

The tool path data correction unit 21 corrects the position of the tool center CL so as to eliminate the separation of the tool TL from the machining curved surface CS and the entry of the tool TL into the machining curved surface CS. In this way, the tool path correction device 100 can correct the tool path correction data so that the tip of the tool used for machining can be prevented from being separated from the object to be machined and from being bitten into the object to be machined.

The tool path data correction unit 21 corrects the direction of the tool axis vector TV to alleviate abrupt changes in tool posture and smooth changes in tool posture. Thereby, the tool path correction device 100 can correct the tool path data so that the change in tool posture becomes a smooth change.

The tool path correction device 100 can determine and extract a command point set as a correction target and define a correction target range based on the tool path data and the arrangement data by the correction target extraction unit 18 and the correction range defining unit 19. The tool path data correction unit 21 corrects the tool path data based on the machining shape data and the tool data. The tool path correction device 100 can also correct the tool path data by importing the data other than during the NC control operation. The tool path correction device 100 can correct the tool path data before the actual machining is performed. The tool path correction device 100 is provided with a corrected tool path data storage unit 22, and thus can store corrected tool path data before actual machining is performed. In the preparation stage before the actual machining, the user can read the corrected tool path data from the tool path correction device 100 and confirm the corrected tool path data. In addition, the user can compare the tool path data before correction with the tool path data after correction in the preparation stage.

The tool path data correction unit 21 corrects the tool posture for each command point to smooth the change in the tool posture. The tool path correction device 100 can correct the tool path data so that the change in tool posture becomes a smooth change without reducing the machining speed.

The tool path data correction unit 21 extracts the command points determined to be the object of correction by the correction object extraction unit 18, and the correction object range including the extracted command points is defined by the correction range definition unit 19. The tool path correction device 100 can shorten the time required for correction of the tool path data, compared with the case where the process for correction is performed as in the case of the whole of the tool path data without performing the extraction and the demarcation as described above.

According to embodiment 1, the tool path correction device 100 can correct the tool path correction data by correcting the position of the tool center so that the separation of the tip of the tool from the object to be processed and the biting into the object to be processed can be suppressed. The tool path correction device 100 can suppress cutting residues due to separation of the tip of the tool from the object to be machined and excessive cutting caused by biting of the tip of the tool into the object to be machined by correction of the tool path correction data, thereby suppressing degradation of the machining quality. In addition, the tool path correction device 100 can correct the tool path correction data by correcting the tool posture so that the change in the tool posture becomes a smooth change. The tool path correction device 100 can suppress a decrease in processing quality due to a sudden change in tool posture by correction of the tool path correction data. This makes it possible for the tool path correction device 100 to suppress degradation of the machining quality.

Embodiment 2.

Fig. 19 is a block diagram showing a functional configuration of NC apparatus 200 according to embodiment 2 of the present invention. The NC apparatus 200 includes an interpolation processing unit 41 and a drive control unit 42, instead of the corrected tool path data storage unit 22 included in the tool path correction apparatus 100 according to embodiment 1. In embodiment 2, the same reference numerals are given to the same parts as those in embodiment 1, and mainly different configurations from embodiment 1 will be described. The NC apparatus 200 corrects the tool path data, and performs numerical control based on the corrected tool path data. The machine tool processes the object in accordance with a command from the NC apparatus 200. Fig. 19 omits illustration of the work machine.

The tool path data correction unit 21 outputs the corrected tool path data to the interpolation processing unit 41 in the same manner as in embodiment 1. The interpolation processing unit 41 is a functional unit that performs interpolation processing of positions and angles. The interpolation processing unit 41 obtains the movement amount for each control cycle based on the corrected tool path data for each of the 3 translation axes for changing the position of the tool, and generates a position to be an interpolation point. The interpolation processing unit 41 obtains the rotation angle for each control cycle based on the corrected tool path data for each of the 2 rotation axes for changing the tool posture, and generates an angle to be an interpolation point. The interpolation processing unit 41 outputs information on interpolation points generated for each axis of the translation axis and each axis of the rotation axis to the drive control unit 42.

The drive control unit 42 is a functional unit that controls the driving of the servo motor for each axis. The drive control unit 42 generates a motor drive control signal for controlling the drive of the servo motor for each axis based on the information of the interpolation point. The drive control unit 42 outputs the generated motor drive control signal to the servo motor of each shaft.

The hardware configuration of the NC apparatus 200 is the same as that of the tool path correction apparatus 100 shown in fig. 2. Each functional unit of the NC apparatus 200 shown in fig. 19 is realized by executing an NC program for executing the NC control method according to embodiment 2 by hardware. The NC program may be stored in a computer readable storage medium. The NC apparatus 200 may store the NC program stored in the storage medium in the external storage device 34. The storage medium may be a floppy disk, i.e., a removable storage medium, or a semiconductor memory, i.e., a flash memory. The NC program may be installed from another computer or a server apparatus to a computer serving as the NC apparatus 200 via a communication network. The functions of NC apparatus 200 can be realized by a processing circuit which is dedicated hardware for numerical control. The functions of NC apparatus 200 may be implemented in part by dedicated hardware and in part by software or firmware.

Fig. 20 is a flowchart showing a sequence of operations performed by NC apparatus 200 shown in fig. 19. Steps S1 to S4 are the same as steps S1 to S4 shown in fig. 3. In step S51, the interpolation processing unit 41 performs interpolation processing for generating interpolation points. In step S52, the drive control unit 42 generates a motor drive control signal, and outputs the generated motor drive control signal. Thereby, the NC apparatus 200 ends the operations performed in the sequence shown in fig. 20. The NC apparatus 200 can correct the tool path data in the NC apparatus 200, and thus can immediately cause the machine tool to perform machining based on the corrected tool path data after the correction of the tool path data is completed.

According to embodiment 2, nc apparatus 200 can suppress a decrease in processing quality by correcting the position of the tool center and correcting the tool posture, as in tool path correction apparatus 100 according to embodiment 1. This can suppress degradation of the machining quality in NC apparatus 200.

The configuration shown in the above embodiment shows an example of the content of the present invention, and other known techniques may be combined, and a part of the configuration may be omitted or changed without departing from the scope of the present invention.

Description of the reference numerals

10 Tool path data input section, 11 tool path data storage section, 12 machining shape data input section, 13 machining shape data storage section, 14 tool data input section, 15 tool data storage section, 16 setting input section, 17 setting storage section, 18 correction object extraction section, 19 correction range demarcation section, 20 correction object range storage section, 21 tool path data correction section, 22 correction tool path data storage section, 31cpu,32ram,33rom,34 external storage section, 35 input/output interface, 36 bus, 41 interpolation processing section, 42 drive control section, 100 tool path correction device, 200NC device.

Claims

1. A tool path correction device corrects tool path data representing a movement path of a tool relative to a processing object to be processed using the tool,

The tool path correction device is characterized in that,

The tool path data is data representing a position of a tool center and containing a command point associated with a tool pose at the position,

The tool path correction device comprises:

A correction target extraction unit that extracts, from the tool path data, a command point that is determined to be a target of correction based on a movement amount of the tool center and a change amount of the tool posture among the command points adjacent to each other in the movement path; and

A tool path data correction unit configured to correct a position of the tool center and the tool posture at each command point included in a range defined by the command point extracted by the correction target extraction unit, with reference to machining shape data indicating a machining shape to be set as a target in machining of the machining target,

The tool path data correction unit obtains, for each of the command points, a contact point between a machining curved surface represented by the machining shape data and a contour of a tool represented by tool data representing a shape of the tool, and corrects a position of the tool center based on a result of calculating a deviation of the contour of the tool from the contact point, the deviation being generated by correction of the tool posture.

2. The tool path correction device according to claim 1, wherein,

Comprises a correction range defining unit for defining a range of a plurality of command points including the command point extracted by the correction target extracting unit,

The tool path data correction unit corrects the position of the tool center and the tool posture of the command point within the range defined by the correction range definition unit.

3. The tool path correction device according to claim 1 or 2, characterized in that,

A tool axis vector representing the tool posture and a vector representing a direction from the tool center toward a tool reference point which is a reference in the change of the tool posture are associated with the command point,

The tool path data correction unit corrects the tool axis vector by smoothing the position of the tool reference point in the command point in the defined range.

4. The tool path correction device according to claim 1 or 2, characterized in that,

The tool path data correction unit corrects the tool axis vector by performing a filter process on coordinates representing the position of the tool reference point in the command point within the defined range, thereby correcting the position of the tool reference point.

5. The tool path correction device according to claim 1 or 2, characterized in that,

The tool path data correction unit generates an approximation curve based on the tool reference points at the command points in the defined range, and corrects the tool axis vector by adjusting the intervals between the tool reference points on the approximation curve to correct the positions of the tool reference points.

6. A tool path correction device corrects tool path data representing a movement path of a tool relative to a processing object to be processed using the tool,

The tool path correction device is characterized in that,

The tool path correction device comprises:

7. A tool path correction device corrects tool path data representing a movement path of a tool relative to a processing object to be processed using the tool,

The tool path correction device is characterized in that,

The tool path correction device comprises:

8. A tool path correction device corrects tool path data representing a movement path of a tool relative to a processing object to be processed using the tool,

The tool path correction device is characterized in that,

The tool path correction device comprises:

9. A tool path correction method corrects tool path data representing a moving path of a tool relative to a processing object to be processed using the tool by a tool path correction device,

The tool path correction method is characterized in that,

The tool path correction method comprises the following steps:

Extracting, from the tool path data, a command point determined to be a target of correction based on a movement amount of the tool center and a change amount of the tool posture among the command points adjacent in the movement path; and

Correcting the position of the tool center and the tool posture at each command point included in the range defined by the command points extracted by the step with reference to processing shape data indicating a processing shape to be set as a target in processing the processing object,

In the step of correcting the position of the tool center and the tool posture, a contact point between a machining curved surface represented by the machining shape data and a tool contour represented by tool data representing the shape of the tool is obtained for each of the command points, and the position of the tool center is corrected based on a result of calculating a deviation of the tool contour from the contact point, which is generated by the correction of the tool posture.

10. A numerical control device performs numerical control based on tool path data indicating a movement path of a tool relative to a processing object to be processed using the tool,

The numerical control device is characterized in that,

The numerical control device comprises:

The tool path data correction unit obtains, for each of the command points, a contact point between a machining curved surface represented by the machining shape data and a contour of a tool represented by tool data representing a shape of the tool, corrects a position of the tool center based on a result of calculating a deviation of the contour of the tool from the contact point, the deviation being generated by correction of the tool posture,

The numerical control device performs numerical control based on the corrected tool path data.