Lathe, lathe processing system, and lathe cutting edge position estimation method

Abstract

The lathe includes a tool holder having a holder reference point and capable of mounting a tool having a cutting edge, a tool rest including multiple mounting surfaces and a tool rest origin, and a numerical control device including a memory and a processor. The memory stores a first distance in a first direction between the holder reference point of the tool holder and the tool rest origin when a mounting surface of the multiple mounting surfaces to which the tool holder is attached is positioned at an index position and the tool to be mounted is attached to the tool holder. The processor acquires an identifier of the tool to be mounted, and acquires a second distance corresponding to an identifier of a candidate tool that matches the identifier of the tool to be mounted from a storage device that stores a first correspondence relationship between an identifier of a candidate tool mountable to the tool holder and a second distance in the first direction between the holder tool reference point and the cutting edge when the mounting surface is positioned at the index position and the candidate tool is mounted to the tool holder. The processor estimates a third distance in the first direction between the tool rest origin and the cutting edge of the tool to be mounted based on the second distance and the first distance.

Description

Technical Field

[0001] The present invention relates to a lathe, a lathe processing system, and a method for estimating the cutting edge position of a lathe.

Background Art

[0002] As technologies for estimating the cutting edge position of a machine tool, the technologies according to Patent Document 1 and Patent Document 2 are known. Patent Document 1 discloses a technique for measuring the positional deviation between the cutting edge position where a tool is directly attached to a tool spindle and the cutting edge position where a tool is attached to the tool spindle via an attachment, and storing the positional deviation. Patent Document 2 discloses a mathematical model for obtaining the positional deviation of the cutting edge position from the positional deviation parameter of an angle head, which is one of the attachments, and the dimensional parameter of the tool when the angle head is used. In these machine tools, the orientation of the tool can be adjusted by exchanging the attachment.

[0003] On the other hand, there are also machine tools that can switch the attachment to be used by moving the attachment surface of the tool used for processing while keeping a plurality of tools attached to a plurality of attachment surfaces of the tool rest without exchanging the attachment as in Patent Documents 1 and 2. Patent Document 3 discloses a turret lathe, which is an example of such a machine tool. Patent Document 4 discloses a tool rest to which a plurality of tools are attached in a comb-like shape, which is another example of such a machine tool.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

[0005] The technologies described in Patent Documents 1 and 2 assume that the attachment can be mounted on the tool spindle with high reproducibility to the extent that the misalignment of the tool's cutting edge position is negligible, and that once the misalignment is measured, the measured misalignment can be reused when the same attachment is mounted on the tool spindle. However, the tool holder described in Patent Document 3 and the tool mounting part described in Patent Document 4, which are configured to mount the tool to the tool post, cannot always be mounted on the tool post with such high reproducibility. In addition, if the mounting surface of the lathe's tool post changes, the offset amount between the origin of the tool post and the mounting surface may also change. Therefore, each time a tool was mounted on the lathe's tool post, the amount of misalignment between the tool's cutting edge position and the reference position of the tool post had to be measured. As a result, there was a problem that the setup of the machine tool took a lot of time.

[0006] The object of the technology disclosed in this application is to provide a lathe, a lathe machining system, and a method for estimating the cutting edge position of a lathe, which can shorten the setup time for measuring the positional deviation of the cutting edges of multiple tools in a lathe capable of simultaneously mounting multiple tools on the tool post. [Means for solving the problem]

[0007] A lathe according to a first aspect of this disclosure comprises a tool holder, a tool post, an actuator, and a numerical control device. The tool holder has a holder reference point and is capable of mounting a tool having a cutting edge. The tool post includes a plurality of mounting surfaces and has a tool post origin. Each of the plurality of mounting surfaces is capable of mounting a tool holder. The actuator is configured to move the tool post so that each of the plurality of mounting surfaces is positioned at an indexing position. The indexing position is predetermined based on the structure of each lathe and is configured to be machined with a tool mounted on the mounting surface moved to the indexing position. The numerical control device is configured to control the actuator. The numerical control device comprises a memory and a processor. The processor is preferably a hardware processor. The memory stores a first distance in a first direction between the holder reference point of the tool holder and the tool post origin when the mounting surface on which the tool holder is mounted is positioned at an indexing position and the tool to be mounted is mounted on the tool holder. The processor obtains the identifier of the tool to be mounted, and from a storage device that stores the identifiers of candidate tools that can be mounted on the tool holder and a first correspondence between the holder reference point and the cutting edge in a first direction when the mounting surface is positioned at the indexing position and the candidate tool is mounted on the tool holder, it obtains the identifier of the candidate tool that matches the identifier of the tool to be mounted and the corresponding second distance, estimates the third distance in a first direction between the tool post origin and the cutting edge of the tool to be mounted based on the obtained second distance and first distance, and controls the actuator based on the third distance. This storage device may be the memory described above, or it may be a storage device provided outside the lathe. Furthermore, it is desirable that the second distance is a value measured with the candidate tool removed from the tool holder.

[0008] According to a second aspect of this disclosure, in the lathe according to the first aspect, the tool has a tool reference point that substantially coincides with the holder reference point when mounted on the tool holder, and the second distance is the distance in a first direction between the tool reference point and the cutting edge. If the tool is mounted on the tool holder via an adapter, the tool reference point may be outside the tool. Alternatively, a tool with an adapter may be considered as the tool.

[0009] According to a third aspect of the present disclosure, in a lathe according to the first or second aspect, the tool post is a turret. Preferably, the multiple mounting surfaces are multiple surfaces formed for mounting tool holders that define a single turret.

[0010] According to a fourth aspect of this disclosure, in the lathe according to the third aspect, the first distances of the multiple mounting surfaces differ for each mounting surface. The difference between the maximum and minimum values ​​of the first distances of the multiple mounting surfaces is greater than the range of variation in the distance between the holder reference point and the cutting edge in the first direction when the same tool is mounted on the tool holder.

[0011] According to a fifth aspect of this disclosure, in a lathe according to a fourth aspect, the range of variation in the position of the holder reference point in the first direction when tool holders are mounted on the same mounting surface is greater than the range of variation in the distance between the holder reference point and the cutting edge in the first direction when the same tool is mounted on the tool holder.

[0012] According to the sixth aspect of this disclosure, in a lathe according to any of the third to fifth aspects, the tool post is rotatable about a rotation axis passing through the origin of the tool post, and the first direction is perpendicular to the rotation axis or parallel to the rotation axis.

[0013] According to a seventh aspect of this disclosure, the lathe according to the sixth aspect further comprises a workpiece holding device for gripping a workpiece so as to be rotatable around a workpiece rotation axis parallel to the rotation axis. The first direction is perpendicular to both the rotation axis and the workpiece rotation axis.

[0014] According to the eighth aspect of this disclosure, in a lathe according to the first or second aspect, the multiple mounting surfaces are provided on the same plane.

[0015] According to the ninth aspect of this disclosure, in the lathe according to the eighth aspect, the first direction is the direction of the normal to the coplane, or a direction perpendicular to the normal direction.

[0016] According to the tenth aspect of this disclosure, in a lathe according to any of the first to ninth aspects, the memory is when the mounting surface is positioned at the indexing position and the tool to be mounted is attached to the tool holder. This coincides with the tool reference point of the tool to be mounted. The processor stores the identifier of the candidate tool and the fourth distance in a second direction perpendicular to the first direction between the holder reference point of the tool holder and the origin of the tool post. The tool reference point of the candidate tool and the cutting edge of the candidate tool coincide with the holder reference point. From a memory device that stores the third correspondence with the fifth distance in the second direction, the identifier of a candidate tool that matches the identifier of the tool to be mounted and the corresponding fifth distance are obtained, and based on the obtained fifth distance and fourth distance, the distance between the tool post origin and the cutting edge of the tool to be mounted is determined. In the second direction The sixth distance is estimated, and the actuator is controlled based on the sixth distance.

[0017] According to an eleventh aspect of the present disclosure, in a lathe according to any of the first to tenth aspects, the tool has a tool axis and the tool holder has a target axis. The tool holder includes one of a guide surface and a guided surface configured to be guided by the guide surface, configured to move closer to the target axis as it moves toward the insertion direction from one of the tool holder or the tool toward the other, so as to make the tool axis substantially coaxial with the target axis; one of at least two attitude adjustment surfaces and at least two contact surfaces configured to contact at least two attitude adjustment surfaces intersecting a circumferential direction about the coaxiality; and one of a locking claw that regulates or deregulates the movement of the tool in the insertion direction and the removal direction opposite to the insertion direction and a locking groove provided around the coaxiality and configured to engage with the locking claw. The tool includes the other of a guide surface and a guided surface, the other of at least two attitude adjustment surfaces and at least two contact surfaces, and the other of a locking claw and a locking groove.

[0018] According to a twelfth aspect of the present disclosure, in the lathe according to any one of the first to eleventh aspects, the tool holder is capable of attaching a measuring tool having a measurement target. The first distance is obtained from the measured value of the distance in the first direction between the measurement target and the tool rest origin with the mounting surface disposed at the detection position and the measuring tool attached to the tool holder, and is based on the seventh distance in the first direction between the holder reference point and the measurement target when the mounting surface is disposed at the detection position and the measuring tool is attached to the tool holder. Note that it is desirable that the measuring tool has the tool reference point described above, and the seventh distance is the distance in the first direction between the tool reference point and the measurement target.

[0019] According to a thirteenth aspect of the present disclosure, in the lathe according to any one of the first to twelfth aspects, the memory stores a second correspondence relationship among the identifier of the mounting surface, the first distance, and the identifier of the attached tool. The processor acquires the identifier of the mounting surface disposed at the detection position, and determines the first distance and the identifier of the attached tool based on the acquired identifier of the mounting surface.

[0020] According to a fourteenth aspect of the present disclosure, in the lathe according to the twelfth aspect, the memory stores a fourth correspondence relationship among the identifier of the mounting surface, the fourth distance, and the identifier of the attached tool. The processor acquires the identifier of the mounting surface disposed at the detection position, and determines the fourth distance and the identifier of the attached tool based on the acquired identifier of the mounting surface.

[0021] A lathe processing system according to a fifteenth aspect of the present disclosure includes the lathe according to the thirteenth or fourteenth aspect, a tool presetter configured to measure a second distance related to a measured tool, which is a tool specified by the acquired identifier, with the measured tool removed from the tool holder, a numerical control device, a network for communicating between the numerical control device and the tool presetter, and a storage device connected to the network. The storage device stores a first correspondence relationship associating data representing the identifier of the measured tool and the measured second distance. The processor acquires the second distance corresponding to the identifier of the measured tool that matches the identifier of the attached tool.

[0022] The tool tip position estimation method for a lathe according to the 16th aspect of the present disclosure includes preparing a tool holder that has a holder reference point and to which a tool having a tool tip can be attached, and preparing a tool rest that has a tool rest origin and includes a plurality of mounting surfaces. The method includes mounting the tool holder on a mounting surface among the plurality of mounting surfaces, and attaching a measuring tool having a measurement target to the tool holder. The method includes moving the tool rest so that the mounting surface is disposed at a determined position, and measuring a distance in a first direction between the measurement target and the tool rest origin. The method includes obtaining a seventh distance in the first direction between the holder reference point and the measurement target when the mounting surface is disposed at the determined position and the measuring tool is attached to the tool holder. The method includes obtaining a first distance in the first direction between the tool rest origin and the holder reference point based on the measured distance and the seventh distance, and storing the first distance. The method includes obtaining an identifier of the tool to be measured, measuring a second distance in the first direction between the holder reference point of the tool to be measured and the tool tip when the mounting surface is disposed at the determined position and the tool to be measured is attached to the tool holder, and storing a first correspondence relationship associating the identifier of the tool to be measured and the second distance. The method includes attaching the tool to be mounted to the tool holder and disposing the mounting surface at the determined position. The method includes obtaining an identifier of the tool to be mounted, obtaining a second distance corresponding to the identifier of the tool to be measured that matches the identifier of the tool to be mounted, and estimating a third distance in the first direction between the tool rest origin and the tool tip of the tool to be mounted based on the obtained second distance and the first distance.

[0023] According to the 17th aspect of the present disclosure, in the tool tip position estimation method according to the 16th aspect, the tool has a tool reference point that substantially coincides with the holder reference point when the tool is attached to the tool holder, and the second distance is the distance in the first direction between the tool reference point and the tool tip. When the tool is attached to the tool holder via an adapter, the tool reference point may be outside the tool. Alternatively, the tool with an adapter may be regarded as the above tool. Further, it is desirable that the measuring tool has the tool reference point described above, and the seventh distance is the distance in the first direction between the tool reference point and the measurement target.

[0024] According to the eighteenth aspect of this disclosure, in the cutting edge position estimation method according to the sixteenth or seventeenth aspect, the tool post is a turret. Preferably, the multiple mounting surfaces are multiple surfaces formed for mounting tool holders that define a single turret.

[0025] According to the 19th aspect of this disclosure, in the cutting edge position estimation method according to the 18th aspect, the difference between the maximum and minimum values ​​of the first distances of the multiple mounting surfaces is greater than the range of variation in the distance between the holder reference point and the cutting edge in the first direction when the same tool is mounted on the tool holder.

[0026] According to the 20th aspect of this disclosure, in the cutting edge position estimation method according to the 19th aspect, the range of variation in the position of the holder reference point in the first direction when the tool holder is mounted on the same mounting surface is greater than the range of variation in the distance between the holder reference point and the cutting edge in the first direction when the same tool is mounted on the tool holder.

[0027] According to the 21st aspect of this disclosure, in the cutting edge position estimation method according to any of the 18th to 20th aspects, the tool post is rotatable about a rotation axis passing through the origin of the tool post, and the first direction is a direction perpendicular to the rotation axis or a direction parallel to the rotation axis.

[0028] According to the 22nd aspect of this disclosure, the cutting edge position estimation method according to the 21st aspect is such that the first direction is perpendicular to both the rotation axis and the workpiece rotation axis. The workpiece mounted on the lathe is gripped so as to be rotatable around a workpiece rotation axis parallel to the rotation axis.

[0029] According to the 23rd aspect of this disclosure, in the cutting edge position estimation method according to the 16th or 17th aspect, the multiple mounting surfaces are provided on the same plane.

[0030] According to the 24th aspect of this disclosure, in the cutting edge position estimation method according to the 23rd aspect, the first direction is the normal direction of the coplane, or a direction perpendicular to the normal direction.

[0031] According to a 25th aspect of this disclosure, a method for estimating the cutting edge position according to any of the 16th to 24th aspects includes measuring an additional distance in a second direction perpendicular to a first direction between the object to be measured and the tool post origin. The method includes obtaining an eighth distance in the second direction between the holder reference point and the object to be measured when the mounting surface is positioned at the indexing position and the measuring tool is attached to the tool holder. The method includes determining a fourth distance in the second direction between the tool post origin and the holder reference point based on the measured additional distance and the eighth distance, and storing the fourth distance. The method includes determining an additional distance in the second direction between the tool post origin and the holder reference point when the mounting surface is positioned at the indexing position and the tool to be measured is attached to the tool holder. It substantially coincides with the holder reference point. The tool being measured tool The method includes measuring a fifth distance in a second direction between a reference point and the cutting edge, and storing a third correspondence between the identifier of the tool being measured and the fifth distance. The method includes obtaining the identifier of the tool being mounted, obtaining the fifth distance corresponding to the identifier of the tool being measured that matches the identifier of the tool being mounted, and estimating a sixth distance in a second direction between the tool post origin and the cutting edge of the tool being mounted based on the obtained fifth distance and fourth distance. 。

[0032] According to a 26th aspect of this disclosure, a cutting edge position estimation method according to any of the 16th to 25th aspects further includes storing a second correspondence between a mounting surface identifier, a first distance, and a mounting tool identifier. The method further includes obtaining the identifier of a mounting surface located at an indexing position, and determining the first distance and the mounting tool identifier based on the obtained mounting surface identifier.

[0033] According to a 27th aspect of this disclosure, the cutting edge position estimation method according to the 25th aspect further includes storing a fourth correspondence between a mounting surface identifier, a fourth distance, and an identifier of the tool to be mounted. The method further includes obtaining an identifier of a mounting surface located at an indexing position, and determining the fourth distance and the identifier of the tool to be mounted based on the obtained mounting surface identifier.

[0034] Machine tools with turret lathes or tool posts that mount tools in a comb-like pattern have numerous mounting surfaces. Therefore, once a tool holder / tool ​​mounting section is attached, it remains fixed to the mounting surface, and the tool attached to the tool holder / tool ​​mounting section is changed during use. On the other hand, the tool holder / tool ​​mounting section can mount tools with high reproducibility to the extent that misalignment of the tool's cutting edge position is negligible. The lathe according to the first embodiment, the machine tool system according to the fifteenth embodiment which includes the lathe according to the first embodiment, and the cutting edge position estimation method according to the sixteenth embodiment utilize these characteristics of machine tools to obtain an identifier for the tool to be mounted when a new tool to be mounted is attached to the tool holder, obtain a second distance using the first correspondence relationship, and estimate a third distance in the first direction between the origin of the tool post and the cutting edge of the tool to be mounted based on the obtained second distance and the first distance. With this configuration, once the tool holder / tool ​​mounting section is fixed to the mounting surface and the first distance to the holder's reference point is stored, the first distance can be reused even if the tool is replaced from the tool holder / tool ​​mounting section. Furthermore, the second distance can be measured by an external tool presetter or the like without attaching the tool to the tool holder / tool ​​mounting section. Therefore, the setup time for measuring the displacement of the cutting edge positions of multiple tools can be reduced.

[0035] The lathe according to the second embodiment, the lathe machining system according to the 15th embodiment equipped with the lathe according to the second embodiment, and the cutting edge position estimation method according to the 17th embodiment are the distance between the cutting edge and the tool reference point, which substantially coincides with the holder reference point when the tool is attached to the tool holder, thus facilitating the measurement of the second distance by an external device.

[0036] The lathe according to the third embodiment, the lathe machining system equipped with the lathe according to the third embodiment, and the cutting edge position estimation method according to the eighteenth embodiment enable the application of the technical features of the first embodiment to multiple mounting surfaces of a turret lathe.

[0037] In the lathe according to the fourth embodiment, the lathe machining system according to the fifteenth embodiment equipped with the lathe according to the fourth embodiment, and the cutting edge position estimation method according to the nineteenth embodiment, the machining error of the multiple mounting surfaces of the turret lathe is greater than the range of positional deviation of the cutting edge position of the tool mounted on the tool holder. Even in such cases, the machining error of the multiple mounting surfaces of the turret lathe is corrected by the first distance of the holder reference point. Therefore, since there is no need to separately calibrate the machining error of the multiple mounting surfaces of the turret lathe, the setup for measuring the amount of deviation of the cutting edge positions of multiple tools can be made even more efficient.

[0038] In the lathe according to the fifth embodiment, the lathe machining system according to the fifteenth embodiment equipped with the lathe according to the fifth embodiment, and the cutting edge position estimation method according to the twentieth embodiment, the variation in the mounting of tool holders to the same mounting surface is greater than the range of positional deviation of the cutting edge position of the tool mounted on the tool holder. Even in such cases, the variation in the mounting of tool holders is corrected by the first distance of the holder reference point. Therefore, since there is no need to separately calibrate the machining errors of multiple mounting surfaces of the turret lathe, the setup for measuring the amount of deviation of the cutting edge positions of multiple tools can be made even more efficient.

[0039] In the lathe according to the sixth embodiment, the lathe machining system according to the fifteenth embodiment equipped with the lathe according to the sixth embodiment, and the cutting edge position estimation method according to the twenty-first embodiment, the lathe moves the turret in a direction perpendicular or horizontal to the rotation axis of the turret lathe during machining, so the offset of the movement direction during machining can be appropriately estimated, and machining can be performed with high precision.

[0040] In the lathe according to the 7th embodiment, the lathe machining system according to the 15th embodiment equipped with the lathe according to the 7th embodiment, and the cutting edge position estimation method according to the 22nd embodiment, the lathe moves the turret in a direction perpendicular to both the rotation axis of the turret lathe and the rotation axis of the workpiece during machining, so that the offset of the movement direction during machining can be appropriately estimated, and machining can be performed with high precision.

[0041] The lathe according to the eighth embodiment, the lathe machining system according to the fifteenth embodiment equipped with the lathe according to the eighth embodiment, and the cutting edge position estimation method according to the twenty-third embodiment make it possible to apply the technical features of the first embodiment to a tool post on which multiple tools are mounted in a comb-like manner.

[0042] In the lathe according to the 9th embodiment, the lathe machining system according to the 15th embodiment equipped with the lathe according to the 9th embodiment, and the cutting edge position estimation method according to the 24th embodiment, the lathe moves the tool post in the direction normal to the same plane or in a direction perpendicular to the normal direction during machining, so the offset of the direction of movement during machining can be appropriately estimated, and machining can be performed with high precision.

[0043] In the lathe according to the 10th embodiment, the lathe machining system according to the 15th embodiment equipped with the lathe according to the 10th embodiment, and the cutting edge position estimation method according to the 25th embodiment, the offset of the cutting edge in the second direction perpendicular to the first direction can be corrected.

[0044] In the lathe according to the 11th embodiment, and the lathe machining system according to the 15th embodiment equipped with the lathe according to the 11th embodiment, the tool holder can position the cutting edge position of the tool with high precision to an error of a few micrometers relative to the holder reference point.

[0045] In the lathe according to the 12th embodiment, the lathe machining system according to the 15th embodiment equipped with the lathe according to the 12th embodiment, and the cutting edge position estimation method according to the 25th embodiment, the first distance can be determined using a measuring tool, making measurement easier than directly measuring the holder reference point. Furthermore, since it is not necessary to directly measure the holder reference point by using a measuring tool, the first distance can be determined even in machines with a limited range of motion of the drive mechanism.

[0046] In the machine tools according to the 13th and 14th embodiments, the machine tool system according to the 15th embodiment which includes the machine tool according to the 12th embodiment, and the cutting edge position estimation methods according to the 26th and 27th embodiments, a first distance (fourth distance) and an identifier for the tool to be mounted can be managed for each mounting surface, allowing for flexible response to rotation of the mounting surface, replacement of the tool to be mounted, etc. [Effects of the Invention]

[0047] The technology disclosed herein can reduce the setup time required to measure the amount of displacement of the cutting edge positions of multiple tools. [Brief explanation of the drawing]

[0048] [Figure 1] Figure 1 is a schematic diagram showing the general configuration of a lathe machining system according to the first embodiment. [Figure 2] Figure 2 is a magnified view of the turret. [Figure 3] Figure 3 shows an example of a tool holder mounted on a turret and a tool that can be attached to the tool holder. [Figure 4] Figure 4 shows an example of a tool post with a tool holder attached. [Figure 5] Figure 5 shows the tool inserted into the tool holder. [Figure 6] Figure 6 is an example of a view of a tool from the tool's central axis. [Figure 7] Figure 7 is a block diagram of the hardware configuration of the lathe machining system according to the first embodiment. [Figure 8] Figure 8 is a schematic diagram of the configuration of the tool mounting section in the tool presetter. [Figure 9] Figure 9 is a schematic diagram showing the dimensions of the tool, tool holder, and tool post according to the first embodiment. [Figure 10] Figure 10 shows an example of tool data. [Figure 11] Figure 11 shows an example of mounting surface data according to the first embodiment. [Figure 12] Figure 12 is a schematic diagram illustrating the method for measuring the holder reference point of a tool holder. [Figure 13] Figure 13 is a flowchart showing the processing flow of the method for estimating the cutting edge position of a lathe. [Figure 14] Figure 14 is a schematic diagram showing the general configuration of a lathe according to the second embodiment. [Figure 15] Figure 15 is a block diagram of the hardware configuration of the lathe machining system according to the second embodiment. [Figure 16] Figure 16 is a schematic diagram showing the dimensions of the tool, tool holder, and tool post according to the second embodiment. [Figure 17] Figure 17 shows an example of mounting surface data according to the second embodiment. [Modes for carrying out the invention]

[0049] The present invention will be described in detail below with reference to the drawings illustrating its embodiments. In the drawings, the same reference numerals indicate corresponding or substantially identical components. <First Embodiment> <Configuration of Lathe 1> Figure 1 is a schematic diagram showing the general configuration of a lathe machining system 100 including a lathe 1 according to a first embodiment of the present invention. A lathe is a machine tool that primarily rotates a workpiece and uses tools such as cutting tools to perform machining such as external turning, boring, parting, face turning, and threading. The lathe machining system 100 includes a lathe 1, a network NW, a computer 99, a tool presetter 95, and a storage device 90 connected to the network NW. The network NW connects the computer 99 to the lathe 1 in order to communicate between the lathe 1 and the tool presetter 95. The computer 99 may be a general-purpose computer including electronic circuits such as a hardware processor and memory. The tool presetter 95 is a device that measures the dimensions of a tool mounted on a turret, such as the device disclosed in Japanese Patent Application Publication No. 3-66552. The computer 99 is used to control the tool presetter 95 and to transmit the tool dimension data measured by the tool presetter 95 to the lathe 1. The network NW may be a wired network such as an intranet or a wireless network such as a wireless LAN. In this embodiment, the storage device 90 is network storage provided on the network NW. This network storage may be, for example, cloud storage on the cloud. The storage device 90 may also be the memory of the computer 99 or the memory of the numerical control device 2, which will be described later.

[0050] In this embodiment, the lathe 1 is a numerically controlled lathe, specifically a turret lathe. A numerically controlled lathe is a lathe that controls the relative motion between the cutting tool and the workpiece using numerical information such as position and speed, and executes a series of operations related to machining by programmed commands. The lathe 1 comprises a numerical control device 2, a base 3, a tool post 4, a tool holder 5, an actuator 6, and a workpiece holding device 7. In this embodiment, the tool post 4 is a turret 40 having a plurality of mounting surfaces 8. The actuator 6 includes a swivel drive device 60 configured to swivel the turret 40 around a first axis AX1, and a translation drive device 61 that moves the turret 40 on the base 3. The translation drive device 61 may be omitted. The first axis AX1 is along the Z axis of the three-dimensional Cartesian coordinate system shown in the figure. The swivel drive device 60 is, for example, a motor. The swivel drive device 60 is configured to position the turret 40 at a predetermined rotational position around the first axis AX1. Therefore, if the slewing drive device 60 is a stepping motor or servo motor capable of controlling the rotational position in a feedforward manner, it is preferable to include a rotational position detection sensor such as an encoder for positioning the turret 40 to a predetermined rotational position around the first axis AX1.

[0051] The translational drive unit 61 includes a first drive unit 62 configured to move the tool post 4 in the Z-axis direction, and a second drive unit 64 configured to move it in the X-axis direction of a three-dimensional Cartesian coordinate system that is perpendicular to the Z-axis direction and intersects the horizontal direction DH. The Y-axis direction of the three-dimensional Cartesian coordinate system is perpendicular to both the X-axis and Z-axis directions. The X-axis direction is the direction in which the tool T attached to the turret 40 is translated when machining a workpiece. In this embodiment, the X-axis direction is inclined 30 degrees from the vertical direction. The orientation of the X-axis direction varies depending on the structure of the lathe 1. The translational drive unit 61 (first drive unit 62, second drive unit 64) consists of, for example, a motor and a ball screw. The translational drive unit 61 is configured to position the rotational position of the motor for positioning the tool post 4. For this reason, it is preferable that the motor is a stepping motor, or that the translational drive unit 61 includes a rotational position detection sensor such as an encoder. Furthermore, although the translational drive device 61 described above is configured not to move the tool post 4 in the Y-axis direction for the sake of simplicity in the explanation, it may also be further equipped with a drive device that moves the tool post 4 in the Y-axis direction.

[0052] The workpiece holding device 7 includes jaws 73 for holding the workpiece, a chuck 72 to which the jaws 73 are attached, and a swivel drive device 71 for rotating the chuck 72 around the second axis AX2. Furthermore, the workpiece holding device 7 may include a drive device having a similar function and configuration to the first drive device 62 configured to move in the Z-axis direction. The second axis AX2 is parallel to the first axis AX1. That is, the second axis AX2 is along the Z-axis of the three-dimensional Cartesian coordinate system. In other words, the workpiece holding device 7 is configured to grip the workpiece so that it can rotate around the workpiece rotation axis (second axis AX2). The X-axis direction is perpendicular to both the first axis AX1 and the second axis AX2, and corresponds to the cutting direction of the workpiece. The swivel drive device 71 is configured to control the rotational speed of the chuck 72. The numerical control device 2 is configured to control the actuators 6 (swivel drive device 60 and translation drive device 61).

[0053] Figure 2 is an enlarged view of the turret 40. Referring to Figure 2, when the turret 40 is viewed in the direction along the first axis AX1, the shape of the turret 40 is essentially a regular polygon centered on the first axis AX1, and each of the multiple mounting surfaces 8 corresponds to one side of the regular polygon. As shown in Figure 2, each of the multiple mounting surfaces 8 is assigned a number, which is called the station number. In the example in Figure 2, there are 12 multiple mounting surfaces 8, and the shape of the turret 40 is a regular dodecagon. In subsequent embodiments, the position of the mounting surface 8 that is directed in the direction of the X-axis from the first axis AX1 is called the indexing position. The T-code number in the machining program corresponds to the station number, and the turret 40 is rotated so that the mounting surface 8 of the station number corresponding to the T-code number is located at the indexing position. In other words, the actuator 6 (swivel drive device 60) is configured to move the tool post 4 so that each of the multiple mounting surfaces 8 is positioned at the indexing position.

[0054] The tool holder 5 can be fitted with a tool T. Figure 3 shows an example of a tool holder 5 mounted on a turret 40 and a tool T fitted to the tool holder 5. Each of the multiple mounting surfaces 8 has multiple mounting holes 8h to which various tool holders 5 can be fitted. Therefore, each of the multiple mounting surfaces 8 can be fitted with a tool holder 5. The multiple mounting holes 8h may include holes for screwing in bolts for fitting the tool holder 5 and holes for passing pins for positioning the tool holder 5. For this reason, a tool holder 5 can be fitted to each of the mounting surfaces 8 of the turret 40, and as shown in Figure 4, a tool holder 5 can be fitted to each of all the mounting surfaces 8 of the turret 40, but it is not necessary for a tool holder 5 to be fitted to at least one of the mounting surfaces 8.

[0055] The tool holder 5 is a device that can be mounted on each of the multiple mounting surfaces 8 and can reproducibly attach the tool T. Reproducibly attachable means that the deviation of the cutting edge position that occurs when the same tool T is attached multiple times is negligibly small in the machining operation (for example, about a few micrometers). The tool holder 5 is either a single holder 5A that can mount one tool T or a double holder 5B that can mount multiple tools T. The single holder 5A includes an insertion hole 5h for inserting the tool shaft TSH of the tool T. The double holder 5B includes insertion holes 5h1 and 5h2 for inserting the tool shaft TSH of the tool T. In order to allow various tools T (Ta1~Ta3, Tb1~Tb3, Tc1~Tc3) to be attached to the tool holder 5, the shapes of the insertion holes 5h, 5h1, and 5h2 are substantially the same. The tool shaft TSH of tools T(Ta1~Ta3, Tb1~Tb3, Tc1~Tc3) is substantially identical in shape.

[0056] Next, the structure of the tool holder 5, which allows for highly reproducible mounting of the tool T, will be described. Figure 5 shows the state in which the tool T is inserted into the tool holder 5. The tool T has the tool shaft TSH described above, a tool flange TFL formed at one end of the tool shaft TSH, a tool central axis Axt which is the central axis of the tool shaft TSH, and a cutting edge ED which contacts the workpiece during machining. Note that the tool T is composed of a head having the cutting edge ED and an adapter having the tool shaft TSH, and the head with the adapter may be considered as the tool T. Figure 6 is an example of a view of the tool T along the tool central axis Axt. In Figure 6, the other end of the tool shaft TSH opposite to the tool flange TFL is shown on the front side. Figures 5 and 6 are examples of structures necessary for a structure that allows for highly reproducible mounting of the tool T, and other shapes are also possible. Specific examples of such shapes include, for example, shapes conforming to the ISO 26623-1 standard, the ISO 12164 standard, and the ISO 26623-1 standard. The side surface of the tool shaft TSH is a tapered surface that follows the tool's central axis Axt, and approaches the central axis Axt as it moves away from the tool flange TFL. This side surface is called the guided surface GEDS. The insertion hole 5h has a side shape that matches the guided surface GEDS of the tool shaft TSH. This side of the insertion hole 5h is called the guide surface GINGS. In other words, the insertion hole 5h has a target central axis Atar that is equidistant from each of the guide surfaces GINGS of the insertion hole 5h. Because the guide surface GINGS has the shape described above, when the tool shaft TSH is inserted all the way into the insertion hole 5h, the tool central axis Axt can be made substantially coaxial with the target central axis Atar. Specifically, the guide surface GINGS is configured to be along the target central axis Atar, and to approach the target central axis Atar as the insertion direction Dins approaches from the tool T toward the tool holder 5. The guided surface GEDS is configured to be guided by the guide surface GINGS.

[0057] Referring to Figure 6, the tool T (tool shaft TSH) has at least two attitude adjustment surfaces OAS (in the example of Figure 6, guided surfaces GEDS that constitute the four sides of a roughly square truncated pyramid) that intersect the circumferential direction DCIR with respect to the tool central axis Axt. The tool holder 5 has at least two contact surfaces CONS (guide surfaces GINGS of the insertion hole 5h) configured to contact at least two attitude adjustment surfaces OAS. This configuration determines the attitude of the tool T around the target central axis Atar.

[0058] Referring to Figures 5 and 6, the tool holder 5 includes a locking claw EC. The tool T (tool shaft TSH) has a shaft hole SHOL and a locking groove GV. The locking claw EC is inserted into the shaft hole SHOL. The locking claw EC is configured to engage with the locking groove GV and disengage the connection by a locking claw sliding mechanism (not shown). When the locking claw EC is engaged with the locking groove GV, the tool T can no longer move relative to the tool holder 5 in the direction along the target central axis Atar and is fixed to the tool holder 5. With this configuration, the tool holder 5 can mount the tool T with high repeatability. However, whether the tool T and tool holder 5 have a guided surface GEDS or a guide surface GINGS, whether they have a locking groove GV or a locking claw EC, or whether they have at least two attitude adjustment surfaces OAS or at least two contact surfaces CONS can be freely determined by design changes, and in any case the tool holder 5 can mount the tool T with high repeatability.

[0059] Figure 7 is a block diagram of the hardware configuration of the lathe machining system 100 according to the first embodiment. The tool presetter 95 acquires the identifier (tool ID) of the tool T and measures the distance to the cutting edge position relative to the holder reference point Ph (described later) from multiple directions. The tool presetter 95 is a device like the one disclosed in Japanese Patent Application Publication No. 3-66552, as described above, but in application of the present invention, it has the following features. Figure 8 is a schematic diagram of the configuration of the tool mounting part in the tool presetter 95. In the example of Figure 8, the tool presetter 95 has a spindle 95S having substantially the same guide surface GINGS, at least two contact surfaces CONS, and locking claw EC structure as the tool holder 5. The spindle 95S is rotatable by a rotating device (gears, handles, or motor, etc.) not shown, and the cutting edge ED can be directed in any direction. The holder reference point Ph is a point determined by the shape of the guide surface GINGS, at least two contact surfaces CONS, the locking claw EC, and the locking groove GV of the tool T. For example, it is the intersection of the rotation axis of the spindle 95S (coaxial with the target central axis Atar) and the reference surface 95P of the spindle 95S that contacts the tool flange TFL of the tool T. When the tool T is mounted on the spindle 95S, the point inside the tool T that substantially coincides with the holder reference point Ph is called the tool reference point. PtThis is referred to as [tool reference point]. The position of the holder reference point Ph (tool reference point Pt) in Figure 8 is an example, and any other position is acceptable as long as it is a point that the tool presetter 95 can identify, which is included in common with all tools T that can be mounted on the tool holder 5 and spindle 95S, and is located in the same position with high reproducibility when mounted on the tool holder 5 and spindle 95S. In this embodiment, the case in which the tool presetter 95 is used has been described, but any other position is acceptable as long as it is located in the same position with high reproducibility when mounted on the tool holder 5, for example, when the cutting edge position of the tool is measured by other means.

[0060] As shown in Figure 8, the tool T has a tag TAG that has an identifier (tool ID) for the tool T. The tag TAG may be, for example, a barcode, but it may also be an RF-ID. When the tool T is mounted on the spindle 95S, the tool presetter 95 reads the tool ID from the tag TAG and measures lengths Ht and Wt, which represent the positional relationship between the holder reference point Ph (tool reference point Pt) and the cutting edge ED. The tool presetter 95 has a well-known tag reader for reading the tool ID from the tag TAG. For example, when the tag TAG is a barcode, the tool presetter 95 has a barcode reader. When the tag TAG is an RF-ID, the tool presetter 95 has an RF-ID reader.

[0061] The computer 99 includes a hardware processor 99P, memory 99M, display 99DS, input interface 99IF, system bus 99SB, external I / O interface 99IO, and communication interface 99CF. The tool presetter 95 is connected to the computer 99 via an external I / O interface 99IO such as RS-232C, USB, or LAN. The computer 99 is connected to the network CW via the communication interface 99CF. With these configurations and the execution of a well-known control program and data transmission / reception program for the tool presetter 95, the computer 99 obtains the measured dimensions and identifier of the tool under test from the tool presetter 95 and sends the obtained data to the storage device 90. The storage device 90 stores the dimensions and identifier of the tool under test in association. The tool data 46 in the figure corresponds to the data associating the dimensions and identifier of the tool under test.

[0062] Figure 9 is a schematic diagram showing the dimensions of the tool, tool holder, and tool post according to the first embodiment. Figure 10 shows an example of tool data 46. As shown in Figure 9, the tool holder 5 has substantially the same guide surface GINGS, at least two contact surfaces CONS, and locking claw EC structure as the spindle 95S, and therefore has a holder reference point Ph corresponding to these shapes. The lengths Ht and Wt, which represent the positional relationship between the holder reference point Ph (tool reference point Pt) and the cutting edge ED when the tool T is attached to the tool holder 5, match the measurement results from the tool presetter 95. Length Ht is the distance between the tool reference point Pt and the cutting edge ED in the DT1 direction along the tool central axis Axt. Length Wt is the distance between the tool reference point Pt and the cutting edge ED in the DT2 direction, which is radial with respect to the tool central axis Axt.

[0063] Referring to Figure 10, the tool data 46 includes the correspondence between the tool identifier (tool ID), length Ht, and length Wt of tool T. The tool T defined in the tool data 46 may also be called the tool under test or the candidate tool. Although the correspondence is represented in a table format in Figure 10, the tool data 46 may be represented in any data structure that can describe such a correspondence. Lists, arrays, and databases are examples of such data structures.

[0064] The numerical control device 2 includes an electronic circuit such as an electronic control unit, information processing means such as a hardware processor 2P, storage means such as memory 2M, and a system bus 2SB that connects the hardware processor 2P to other hardware. The numerical control device 2 includes a control panel 2CP that allows information input and output to an operator, such as a touch panel display. The touch panel of the control panel 2CP may be called an input interface 2IF, and the display of the control panel 2CP may be called a display 2DS. In addition to the touch panel, the numerical control device 2 may further include input interfaces 2IF such as buttons or dials. The numerical control device 2 further includes a communication interface 2CF that connects to a network NW, and can acquire at least a portion of the tool data 46 stored in the storage device 90 via the communication interface 2CF.

[0065] Memory 2M stores a machining program 41 for machining a workpiece, a position correction program 42, and mounting surface data 45. The position correction program 42 is programmed to estimate the cutting edge position of the tool T specified by the machining program 41 by referring to the mounting surface data 45 and at least a portion of the tool data 46. Therefore, it is desirable that the position correction program 42 be called from the machining program 41. Based on the estimated cutting edge position, the position correction program 42 sends control commands to the servo driver DV that controls the slewing drive unit 60 and the translation drive unit 61. The machining program 41 sends control commands to the inverter INV that controls the slewing drive unit 71 based on the commands in the machining program. The computer 99 further includes a well-known external I / O interface 2IO connected to the servo driver DV and inverter INV for sending these control commands. In other words, the numerical control unit 2 is configured to control the actuator 6.

[0066] Next, the details of the mounting surface data 45 will be described. Figure 11 shows an example of the mounting surface data 45 according to the first embodiment. Figure 9 is a schematic diagram showing the dimensions of the tool holder 5 and the tool post 4 (turret 40) according to the first embodiment. Figure 9 shows the tool holder 5 and the tool post 4 with the X axis in the upward direction of the drawing and the Z axis in the leftward direction of the drawing, and the tool T is shown inserted into such a tool holder 5. The tool post 4 (turret 40) has a tool post origin Ot on the first axis AX1. In other words, the tool post 4 (turret 40) is rotatable around a rotation axis (first axis AX1) passing through the tool post origin Ot. The DT1 direction described above generally coincides with the X-axis direction, and the DT2 direction described above generally coincides with the Z-axis direction. Strictly speaking, due to mounting errors of the tool holder 5, the position of the cutting edge ED may be slightly shifted in the Y-axis direction from a plane that passes through the tool post origin Ot and is parallel to both the X and Z axes. However, since the shift in the Y-axis direction coincides with the tangential direction of the workpiece rotation, its effect on machining accuracy is negligible. In addition, the mounting surface 8 may be slightly tilted from the plane parallel to the Y and Z axes due to machining errors, causing the DT1 direction to be slightly tilted from the X-axis direction and the DT2 direction to be slightly tilted from the Z-axis direction. However, since the size of the tool T is small, the displacement of the cutting edge ED due to this shift is negligible.

[0067] As described above, when the tool T is mounted on the tool holder 5, it has a tool reference point Pt that substantially coincides with the holder reference point Ph. Since the tool holder 5 can mount the tool T with high reproducibility, it can be assumed that the tool reference point Pt will be the same point regardless of which tool T that can be mounted on the tool holder 5 is mounted on the tool holder 5. Referring to Figure 11, the mounting surface data 45 includes the identifier of the mounting surface (mounting surface ID) on which the tool holder 5 is mounted among the multiple mounting surfaces 8, the distance Hh in the X-axis direction and the distance Wh in the Z-axis direction between the tool post origin Ot and the holder reference point Ph, and the correspondence with the tool T mounted on the tool holder 5. In the following description, the tool T defined in the mounting surface data 45 may be referred to as the mounted tool. In Figure 11, the correspondence is represented in a table format, but the tool data 46 may be represented in any format that can describe such a correspondence. Lists, arrays, and databases are examples of such data structures.

[0068] The numerical portion of the mounting surface ID represents the station number. The suffix (A, B) shown after the number in the mounting surface ID is provided to distinguish between the different insertion holes 5h1 and 5h2 of the double holder when the double holder 5B is mounted on the mounting surface 8 corresponding to that station number. For example, of the two holder reference points Ph defined in the insertion holes 5h1 and 5h2, the one with the larger z-coordinate (closer to the workpiece holding device 7) can be designated as A, and the one with the smaller z-coordinate (further from the workpiece holding device 7) can be designated as B.

[0069] In the following embodiments, one of the distances Hh and Wh will be referred to as the first distance, and the other as the fourth distance. The direction corresponding to the reference direction for the first distance will be referred to as the first direction, and the direction corresponding to the reference direction for the fourth distance will be referred to as the second direction. That is, when distance Hh is the first distance and distance Wh is the fourth distance, the X-axis direction is the first direction and the Z-axis direction is the second direction. When distance Wh is the first distance and distance Hh is the fourth distance, the Z-axis direction is the first direction and the X-axis direction is the first direction. In other words, the first direction is the direction perpendicular to the first axis AX1, or the direction parallel to the first axis AX1.

[0070] According to the definition above, memory 2M stores the first distance (one of Hh and Wh) between the holder reference point Ph of the tool holder 5 and the tool post origin Ot in a first direction (one of the X-axis and Z-axis directions) when the mounting surface is positioned at the indexing position and the tool to be mounted is attached to the tool holder 5. Memory 2M also stores the fourth distance (the other of Hh and Wh) in a second direction (the other of the X-axis and Z-axis directions) that is perpendicular to the first direction between the holder reference point Ph of the tool holder 5 and the tool post origin Ot when the mounting surface is positioned at the indexing position and the tool to be mounted is attached to the tool holder 5. Furthermore, it can be said that memory 2M stores a second correspondence between the identifier of the mounting surface (the numerical part of the mounting surface ID), the first distance, and the identifier of the tool to be mounted (tool ID). It can also be said that memory 2M stores a fourth correspondence between the identifier of the mounting surface, the fourth distance, and the identifier of the tool to be mounted.

[0071] Furthermore, the DT1 direction described above can be considered to coincide with the X-axis direction, and the DT2 direction described above can be considered to coincide with the Z-axis direction. In the following embodiments, the length of length Ht and length Wt that is considered to coincide with the first direction of the DT1 direction and DT2 direction is referred to as the second distance. That is, the second distance is the distance between the tool reference point Pt and the cutting edge ED in the first direction. The length of length Ht and length Wt that is considered to coincide with the second direction of the DT1 direction and DT2 direction is referred to as the fifth distance. That is, the fifth distance is the distance between the tool reference point Pt and the cutting edge ED in the second direction. At this time, the tool presetter 95 is configured to acquire the identifier (tool ID) of the tool T, and to measure the second distance related to the tool to be measured with the tool T identified by the acquired identifier removed from the tool holder 5. The storage device 90 stores a first correspondence between the identifier (tool ID) of a candidate tool (tool to be measured) that can be attached to the tool holder 5 and the second distance (one of Ht and Wt) in a first direction (one of DT1 direction and DT2 direction) between the holder reference point Ph and the cutting edge ED when the mounting surface is positioned at the indexing position and the candidate tool is attached to the tool holder 5. The storage device 90 also stores a third correspondence between the identifier (tool ID) of the candidate tool (tool to be measured) and the fifth distance (the other of Ht and Wt) in a second direction (the other of DT1 direction and DT2 direction) when the candidate tool is attached to the tool holder 5.

[0072] While the tool holder 5 can mount the tool T with high repeatability, the surface machining accuracy of the multiple mounting surfaces is not as high as the repeatability of the tool holder 5. Therefore, the difference between the maximum and minimum values ​​of the first distances of the multiple mounting surfaces 8 is greater than the range of variation in the distance between the holder reference point Ph and the cutting edge ED in the first direction when the same tool T is mounted on the tool holder 5. The difference between the maximum and minimum values ​​of the second distances of the multiple mounting surfaces 8 is greater than the range of variation in the distance between the holder reference point Ph and the cutting edge ED in the second direction when the same tool T is mounted on the tool holder 5.

[0073] While the tool holder 5 can mount the tool T with high reproducibility, the reproducibility of mounting the tool holder 5 is not as high as the reproducibility of the tool holder 5 itself. Therefore, the range of variation in the position of the holder reference point Ph in the first direction when the tool holder 5 is mounted on the same mounting surface 8 is greater than the range of variation in the distance between the holder reference point Ph and the cutting edge ED in the first direction when the same tool T is mounted on the tool holder 5. The range of variation in the position of the holder reference point Ph in the second direction when the tool holder 5 is mounted on the same mounting surface 8 is greater than the range of variation in the distance between the holder reference point Ph and the cutting edge ED in the second direction when the same tool T is mounted on the tool holder 5.

[0074] Next, the method for inputting the tool ID (identifier of the tool to be mounted) in Figure 11 will be explained. The input interface 2IF of the numerical control device 2 has the well-known tag reader described above that can read the tag TAG of the tool T. When the operator attaches the tool T to the tool holder 5, the operator selects and inputs the mounting surface ID corresponding to the insertion hole 5h of the tool holder 5 from the control panel 2CP or the input interface 2IF, and inputs the tool ID of the tool to be mounted from the tag reader, thereby inputting the tool ID of the tool to be mounted in association with the mounting surface ID. When the operator attaches the tool to be mounted to the mounting surface of the tool post, the tag reader built into the turret tool post may read the tool to be mounted, and if the tool to be mounted does not match the correspondence, an alarm may be displayed on the screen.

[0075] Next, the measurement and input methods for distances Hh and Wh will be described. Figure 12 is a schematic diagram showing the measurement method for the holder reference point Ph of the tool holder 5. As shown in Figure 12, the measuring tool PRO is attached to the tool holder 5. The measuring tool PRO is, for example, a probe. The measuring tool PRO includes a tool shaft TSH having the same configuration as the tool shaft TSH of the tool T. The measuring tool PRO may further include a tool flange TFL including a locking groove GV or at least two attitude adjustment surfaces OAS. This makes the tool holder 5 capable of mounting the measuring tool PRO. The measuring tool PRO has a sphere B at its tip. The center of the sphere B is called the measurement target Pb. In other words, the measuring tool PRO has the measurement target Pb. The distance Hp between the measurement target Pb and the tool reference point Pt and the radius Wp of the sphere are known. The distance Hm in the X-axis direction between the object Pb and the tool post origin Ot, and the distance Wh in the Z-axis direction between the object Pb and the tool post origin Ot, are measured by a well-known method of applying sphere B to the workpiece holding device 7 or a workpiece of known shape. The distance Hh can be obtained by subtracting the distance Hp from the distance Hm.

[0076] In other words, the first distance (one of Hh or Wh) described above is a value obtained from the measured distance (one of Hm or Wh) between the object to be measured Pb and the tool post origin Ot in a first direction (one of the X-axis direction or the Z-axis direction) when the mounting surface to which the tool holder 5 is attached is positioned at the indexing position and the measuring tool PRO is attached to the tool holder 5, based on the seventh distance (one of Hp or distance 0) between the holder reference point Ph and the object to be measured Pb in a first direction when the mounting surface is positioned at the indexing position and the measuring tool PRO is attached to the tool holder 5. The fourth distance described above (the other of Hh and Wh) is a value obtained from the measured distance (Hm and the other of Wh) between the object to be measured Pb and the tool post origin Ot in a second direction (the other of the X-axis direction and the Z-axis direction) when the mounting surface to which the tool holder 5 is attached is positioned at the indexing position and the measuring tool PRO is attached to the tool holder 5, based on the eighth distance (Hp and the other of distance 0) between the holder reference point Ph and the object to be measured Pb when the mounting surface is positioned at the indexing position and the measuring tool PRO is attached to the tool holder 5.

[0077] The operator selects and inputs the mounting surface ID corresponding to the insertion hole 5h of the tool holder 5 from the control panel 2CP or input interface 2IF, and inputs the measurement results, thereby inputting the distances Hh and Wh in association with the mounting surface ID. Note that the measurement tool PRO is not limited to the probe described above, but may also be a tool T with known lengths Ht and Wt. In that case, the distance in the X-axis direction and the distance in the Z-axis direction between the cutting edge ED of the known tool T and the origin Ot of the tool post may be measured using a gauge or the like, and the distances Hh and Wh may be measured by subtracting the lengths Ht and Wt from the measurement results. In this example, when distance Hh is the first distance, the known length Ht may be referred to as the seventh distance described above, and the known length Wt may be referred to as the eighth distance described above. When distance Wh is the first distance, the known length Wt may be referred to as the seventh distance described above, and the known length Ht may be referred to as the eighth distance described above.

[0078] Next, the method for estimating the position of the cutting edge ED of the tool T using the position correction program 42 will be described. The processor 2P that executes the position correction program 42 performs the process of acquiring the tool ID (identifier of the tool to be mounted) of the mounting surface data 45 via the tag reader (input interface 2IF). Next, the processor 2P performs the process of acquiring the lengths Ht and Wt (second distance, fifth distance) corresponding to the identifier (tool ID of the tool data 46) of a candidate tool (measured tool) that matches the identifier of the tool to be mounted from the storage device 90. After acquisition, the memory 2M may store the tool data 46. Next, the processor 2P acquires the identifier (numerical part of the mounting surface ID) of the mounting surface 8 located at the indexing position from the numbers of the T code described in the machining program 41. Next, the processor 2P determines the distances Hh and Wh and the identifier of the tool to be mounted (tool ID) from the mounting surface data 45 based on the acquired mounting surface identifier. The processor 2P performs a process to estimate the distance Ht+Hh in the X-axis direction between the tool post origin Ot and the cutting edge ED of the tool to be mounted, based on the acquired length Ht and the distance Hh of the mounting surface data 45. Finally, the processor 2P performs a process to estimate the distance Wt+Wh in the Z-axis direction between the tool post origin Ot and the cutting edge ED of the tool to be mounted, based on the acquired length Wt and the distance Wh of the mounting surface data 45. When distance Hh is the first distance and length Ht is the second distance, distance Ht+Hh is referred to as the third distance. When distance Wh is the fourth distance and length Wt is the fifth distance, distance Wt+Wh is referred to as the sixth distance. When distance Wh is the first distance and length Wt is the second distance, distance Wt+Wh is referred to as the third distance. When distance Hh is the fourth distance and length Ht is the fifth distance, distance Ht+Hh is referred to as the sixth distance. The processor 2P, which executes the machining program 41, controls the actuator 6 based on the third distance and the sixth distance. <Processing flow for estimating the cutting edge position of lathe 1> Next, the method for estimating the cutting edge position of the lathe 1 will be explained. Figure 13 is a flowchart showing the processing flow of the method for estimating the cutting edge position of the lathe 1. In Figure 13, in step S11, a tool holder 5 is prepared that has a holder reference point Ph and is capable of mounting a tool T having a cutting edge ED. In step S12, a tool post 4 is prepared that has a tool post origin Ot and includes a plurality of mounting surfaces 8. In step S13, the tool holder 5 is mounted on one of the mounting surfaces 8. In step S14, a measuring tool PRO having a measurement target Pb is attached to the tool holder 5. In step S15, the tool post 4 is moved so that the mounting surface is positioned at the indexing position. In step S16, the distance between the measurement target Pb and the tool post origin Ot in a first direction (either the X-axis direction or the Z-axis direction) (in the example of Figure 12, either distance Hm or distance Wh) is measured. In step S16, the distance between the object to be measured Pb and the tool post origin Ot in a second direction (the other of the X-axis direction and the Z-axis direction) (in the example of Figure 12, the other of the distance Hm and distance Wh) may be measured further.

[0079] In step S17, the method obtains the seventh distance (either Hp or distance 0 in the example of Figure 12) between the holder reference point Ph and the object to be measured Pb in a first direction (either the X-axis direction or the Z-axis direction) when the mounting surface is positioned at the indexing position and the measuring tool PRO is attached to the tool holder 5. This means obtaining known dimensional data of the measuring tool PRO. In step S18, the method obtains the first distance (either Hm or distance Wh in the example of Figure 12) between the tool post origin Ot and the holder reference point Ph in a first direction (either the X-axis direction or the Z-axis direction) based on the measured distance (either distance Hm or distance Wh in the example of Figure 12) and the seventh distance (either Hp or distance 0 in the example of Figure 12). This first distance is stored in memory 2M. In step S18, the method may determine the fourth distance (Hh, the other of Wh) in the second direction (the other of the X-axis direction and the Z-axis direction) between the tool post origin Ot and the holder reference point Ph, based on the measured distance (the other of distance Hm and distance Wh in the example of Figure 12) and the eighth distance (the other of Hp and distance 0 in the example of Figure 12). The fourth distance may be stored in memory 2M.

[0080] In step S19, the tool presetter 95 obtains the identifier (tool ID) of the tool to be measured. In step S20, the tool presetter 95, when the mounting surface is positioned at the indexing position and the tool to be measured is attached to the tool holder 5, This substantially coincides with the holder reference point Ph. The tool being measured Tool reference point Pt The second distance (one of Ht and Wt) between the cutting edge ED and the first direction (one of the X-axis and Z-axis) is measured. In step S20, when the mounting surface of the tool presetter 95 is positioned at the indexing position and the tool to be measured is attached to the tool holder 5, This substantially coincides with the holder reference point Ph. , the tool being measured Tool reference point Pt The fifth distance (the other of Ht and Wt) between the cutting edge ED and the second direction (the other of the X-axis and Z-axis) may also be measured.

[0081] In step S21, the storage device 90 stores a first correspondence relationship associating the identifier of the tool under measurement (tool ID) with a second distance (one of Ht or Wt). In step S21, the storage device 90 may also store a third correspondence relationship associating the identifier of the tool under measurement (tool ID) with a fifth distance (the other of Ht or Wt).

[0082] In step S22, the method involves mounting the tool to be mounted to the tool holder 5. The mounting surface is positioned at the indexing position. In step S23, the method involves the lathe 1 acquiring the identifier (tool ID) of the tool to be mounted. In step S22, the method involves the processor 2P executing the position correction program 42 acquiring a second distance (one of Ht or Wt) corresponding to the identifier of the tool to be measured that matches the identifier of the tool to be mounted, and estimating a third distance (one of Hh+Ht or Wh+Wt) in a first direction (one of the X-axis direction or Z-axis direction) between the tool post origin Ot and the cutting edge ED of the tool to be mounted. In step S22, the processor 2P may obtain a fifth distance (the other of Ht and Wt) corresponding to the identifier of the tool to be measured that matches the identifier of the tool to be mounted, and estimate a sixth distance (the other of Hh+Ht and Wh+Wt) in a second direction (the other of the X-axis and Z-axis) between the tool post origin Ot and the cutting edge ED of the tool to be mounted. <Features and effects of the lathe machining system, the method for estimating the cutting edge position of the lathe 1, etc. in this embodiment> In this embodiment, the lathe 1, the lathe machining system 100, and the method for estimating the cutting edge position of the lathe 1 acquire the identifier of the tool to be mounted, and from the storage device 90 which stores a first correspondence between the identifier of a candidate tool that can be mounted on the tool holder 5 and the second distance in the first direction between the holder reference point Ph and the cutting edge ED when the mounting surface is positioned at the indexing position and the candidate tool is mounted on the tool holder 5, the second distance corresponding to the identifier of the candidate tool that matches the identifier of the tool to be mounted is acquired, and based on the acquired second distance and first distance, the third distance in the first direction between the tool post origin Ot and the cutting edge ED of the tool to be mounted is estimated. This makes it possible to shorten the setup time for measuring tool lengths in order to measure the positional deviation of the cutting edge positions of multiple tools. <Second Embodiment> Figure 14 is a configuration diagram showing the main components of the lathe 1a according to the second embodiment. Figure 15 is a block diagram of the hardware configuration of the lathe machining system 100a according to the second embodiment. The configuration of the second embodiment is largely the same as that of the first embodiment, so only the differences will be explained, and the common components will not be explained.

[0083] As shown in Figure 14, the lathe 1a according to the second embodiment has multiple tools T mounted in a comb-like manner on the tool post 4, and the tool post 4 is moved in the XZ direction to apply it to the workpiece for machining. In this embodiment, such a tool post 4 is referred to as a comb-type tool post 40a. Figure 14 shows a workpiece holding device 7. The workpiece holding device 7 has the same configuration as in the first embodiment. Preferably, the Z-axis direction is along the rotation axis AX2 of the workpiece holding device 7, and the X-axis direction is perpendicular to the rotation axis AX2 of the workpiece holding device 7. The lathe machining system 100a has most of the same configuration as the lathe machining system 100, but in the lathe machining system 100a, the swivel drive device 60 is omitted, and the first and second drive devices 62a and 64a are configured to drive the comb-type tool post 40a in the X-axis direction and the Z-axis direction, respectively.

[0084] In this configuration, the tool holder 5 is mounted in multiple grooves of the comb-tooth tool post 40a. As shown in Figure 14, the back surfaces of the multiple grooves can be considered as multiple mounting surfaces 8. The numbers in parentheses after the reference numerals of the mounting surfaces indicate the station numbers described above. According to Figure 14, the multiple mounting surfaces 8 are located on the same plane (IDP). The tool post origin Ot of the comb-tooth tool post 40a is defined for each lathe 1a. Either a single holder 5A or a double holder 5B capable of mounting multiple tools T can be attached to the mounting surfaces 8. In the first embodiment, the DT1 direction is set to roughly coincide with the X-axis direction, and the DT2 direction described above is set to roughly coincide with the Z-axis direction. In the second embodiment, the DT1 direction is set to roughly coincide with the Z-axis direction, and the DT2 direction described above is set to roughly coincide with the X-axis direction. In this embodiment, since the orientation of the comb-tooth tool post 40a is not changed, it can be assumed that the mounting surface on which the tool holder 5 is attached is positioned at the indexing position among the multiple mounting surfaces 8.

[0085] Figure 16 is a schematic diagram showing the dimensions of the tool holder 5 and the tool post 4 (comb-tooth tool post 40a) according to the second embodiment. Figure 17 shows an example of mounting surface data 45a according to the second embodiment. Referring to Figures 16 and 17, the distance from the holder reference point Ph to the tool post origin Ot is expressed as Wh for the distance in the X direction and Hh for the distance in the Z direction. These values ​​can be obtained by the method shown in the first embodiment. As shown in Figure 17, a double holder 5B may also be mounted in this embodiment, in which case a suffix is ​​written in the mounting surface ID. In this embodiment, the first direction described above can be considered as one of the X-axis direction and the Z-axis direction, and the second direction as the other of the X-axis direction and the Z-axis direction. Therefore, the first direction is the normal direction of the coplane IDP, or a direction perpendicular to the normal direction. The second direction is the normal direction of the coplane IDP, or a direction perpendicular to the normal direction. At this time, the processor 2P executing the position correction program 42 can estimate the distance Hh+Ht in the Z direction between the tool post origin Ot and the cutting edge ED based on the distance Hh and length Ht. At this time, the processor 2P executing the position correction program 42 can estimate the distance Wh+Wt in the X direction between the tool post origin Ot and the cutting edge ED based on the distance Wh and length Wt.

[0086] In this comb-tooth tool post 40a, as shown in the right-hand figure of Figure 16, the model showed that the displacement between the cutting edge ED and the tool post origin Ot does not exist on the Y-axis perpendicular to the X-axis, but the displacement in the Y-axis direction may also be considered. Alternatively, the X-axis may be defined by considering the direction from the Z-axis toward the cutting edge ED as the X-axis. <Variation> Some or all of the logic functions of the position correction program 42 described above may be implemented by a dedicated processor or integrated circuit. The position correction program 42 described above may not be limited to the memory 2M built into the numerical control device 2, but may also be recorded on a storage medium that is removable from the numerical control device 2 and readable by the numerical control device 2, such as a floppy disk, optical disk, CD-ROM and magnetic disk, SD card, USB memory, or external hard disk.

[0087] In this application, “equipped with” and its derivatives are non-restrictive terms that describe the existence of a component and do not exclude the existence of other components not described. This also applies to “having,” “including,” and their derivatives.

[0088] The terms "~member," "~part," "~element," "~body," and "~structure" can have multiple meanings, such as a single part or multiple parts.

[0089] Ordinal numbers such as "1st" and "2nd" are simply terms used to identify components and do not carry any other meaning (such as a specific order). For example, the existence of a "1st element" does not implicitly mean the existence of a "2nd element," nor does the existence of a "2nd element" implicitly mean the existence of a "1st element."

[0090] Unless otherwise specifically stated in the embodiments, terms such as "substantially," "about," and "approximately" can mean a reasonable deviation that does not significantly alter the final result. All numerical values ​​described in this application may be interpreted as including terms such as "substantially," "about," and "approximately."

[0091] In this application, the phrase "at least one of A and B" should be interpreted to include A only, B only, and both A and B.

[0092] Based on the above disclosure, it is clear that various changes and modifications to the present invention are possible. Therefore, the present invention may be implemented in a manner different from the specific disclosures of this application, without departing from the spirit of the invention.

Claims

1. a tool holder having a holder reference point and capable of mounting a tool having a cutting tip; a tool rest including a plurality of mounting surfaces each capable of mounting the tool holder, the tool rest having a tool rest origin; an actuator configured to move the tool rest to position each mounting surface of the plurality of mounting surfaces at an index position; a numerical controller configured to control the actuator; Equipped with The numerical control device includes: a memory that stores a first distance in a first direction between the holder reference point of the tool holder and the tool post origin when a mounting surface to which the tool holder is attached among the plurality of mounting surfaces is disposed at the index position and a tool to be attached is attached to the tool holder; Acquire an identifier of the tool to be attached; obtain, from a storage device that stores a first correspondence relationship between an identifier of a candidate tool that can be attached to the tool holder and a second distance in the first direction between the holder reference point and the cutting edge when the mounting surface is disposed at the index position and the candidate tool is attached to the tool holder, the identifier of the candidate tool that matches the identifier of the attached tool and the second distance corresponding to the second distance; a processor that estimates a third distance in the first direction between the tool post origin and the cutting edge of the attached tool based on the acquired second distance and the acquired first distance, and controls the actuator based on the third distance; Equipped with lathe.

2. the tool has a tool reference point that, when attached to the tool holder, substantially coincides with the holder reference point; The second distance is a distance between the tool reference point and the cutting edge in a first direction.

2. The lathe of claim 1.

3. The tool rest is a turret.

2. The lathe of claim 1.

4. a difference between a maximum value and a minimum value among the first distances of the plurality of mounting surfaces is larger than a range of variation in the distance in the first direction between the holder reference point and the cutting edge when an identical tool is mounted on the tool holder.

4. The lathe of claim 3.

5. a range of variation in the position of the holder reference point in the first direction when the tool holders are attached to the same mounting surface is larger than a range of variation in the distance between the holder reference point and the cutting edge in the first direction when the same tool is attached to the tool holder.

5. The lathe of claim 4.

6. the tool rest is rotatable around a rotation axis passing through the tool rest origin, and the first direction is a direction perpendicular to the rotation axis or a direction parallel to the rotation axis; 4. The lathe of claim 3.

7. The workpiece holding device further includes a workpiece holding device that holds the workpiece rotatably around a workpiece rotation axis that is parallel to the rotation axis, The first direction is a direction perpendicular to both the rotation axis and the workpiece rotation axis.

7. The lathe of claim 6.

8. The plurality of mounting surfaces are provided on the same plane.

2. The lathe of claim 1.

9. The first direction is a normal direction of the same plane or a direction perpendicular to the normal direction.

9. The lathe of claim 8.

10. The memory includes: a fourth distance in a second direction perpendicular to the first direction between the holder reference point of the tool holder and the tool rest origin when the mounting surface is disposed at the index position and the tool is attached to the tool holder; The processor, obtaining, from a storage device that stores a third correspondence relationship between an identifier of the candidate tool and a fifth distance in the second direction when the candidate tool is attached to the tool holder, the fifth distance corresponding to the identifier of the candidate tool that matches the identifier of the attached tool; a sixth distance between the tool rest origin and the cutting edge of the attached tool is estimated based on the acquired fifth distance and fourth distance, and the actuator is controlled based on the sixth distance. A lathe according to any one of claims 1 to 9.

11. The tool has a tool center axis, the tool holder has a target center axis; The tool holder comprises: one of a guide surface and a guided surface configured to be guided by the guide surface, the guide surface being configured to approach the target central axis as the insertion direction from one of the tool holder or the tool to the other along the target central axis, so that the tool central axis is substantially coaxial with the target central axis; one of at least two attitude adjustment surfaces intersecting with a circumferential direction centered on the same axis and at least two abutment surfaces configured to abut against the at least two attitude adjustment surfaces; one of a locking claw that restricts or releases the movement of the tool in the insertion direction and the removal direction opposite to the insertion direction, and a locking groove that is provided around the axis and configured to be engaged with the locking claw; Including, The tool comprises: the other of the guide surface and the guided surface; the other of the at least two attitude adjustment surfaces and the at least two abutment surfaces; the other of the locking claw and the locking groove; Including, A lathe according to any one of claims 1 to 9.

12. The tool holder is capable of mounting a measurement tool having a measurement target, the first distance is a value calculated from a measurement value of a distance in the first direction between the measurement target and the tool post origin when the mounting surface is arranged at the indexing position and the measurement tool is attached to the tool holder, based on a seventh distance in the first direction between the holder reference point and the measurement target when the mounting surface is arranged at the indexing position and the measurement tool is attached to the tool holder. A lathe according to any one of claims 1 to 9.

13. The memory stores a second correspondence relationship between the identifier of the mounting surface, the first distance, and the identifier of the tool to be attached, The processor acquires an identifier of a mounting surface to be placed at the index position, and determines the first distance and an identifier of the tool to be attached based on the acquired identifier of the mounting surface. A lathe according to any one of claims 1 to 9.

14. A lathe according to claim 13; a tool presetter configured to acquire an identifier of a tool, and measure the second distance related to a measured tool, which is a tool identified by the acquired identifier, in a state where the measured tool is removed from the tool holder; A network for communicating between the numerical control device and the tool presetter; The storage device connected to the network; Equipped with the storage device stores the first correspondence relationship that associates the identifier of the tool to be measured with data representing the measured second distance; The processor obtains the second distance corresponding to the identifier of the tool to be measured that matches the identifier of the tool to be attached. Lathe machining system.

15. A tool holder having a holder reference point and capable of mounting a tool having a cutting edge is provided; A tool rest having a tool rest origin and including a plurality of mounting surfaces is provided; The tool holder is attached to a mounting surface of the plurality of mounting surfaces; A measurement tool having a measurement target is attached to the tool holder; moving the tool rest so as to position the mounting surface at an index position; Measuring a distance in a first direction between the measurement object and the tool rest origin; acquiring a seventh distance in the first direction between the holder reference point and the measurement target when the mounting surface is disposed at the index position and the measurement tool is attached to the tool holder; determining a first distance in the first direction between the tool rest origin and the holder reference point based on the measured distance and the seventh distance, and storing the first distance; Obtain an identifier for the tool to be measured; measuring a second distance in the first direction between the holder reference point and the cutting edge of the tool to be measured when the mounting surface is disposed at the index position and the tool to be measured is attached to the tool holder; storing a first correspondence relationship associating an identifier of the tool to be measured with the second distance; A tool to be attached is attached to the tool holder, and the attachment surface is disposed at the index position; Acquire an identifier of the tool to be attached; acquiring the second distance corresponding to an identifier of the measured tool that matches an identifier of the attached tool, and estimating a third distance in the first direction between the tool post origin and the cutting edge of the attached tool based on the acquired second distance and the first distance. A method for estimating the position of a lathe cutting edge.