Numerical control device, control method, program, and storage medium

Abstract

To provide a numerical control device, a control method, a program and a storage medium capable of reducing tool exchange time.SOLUTION: In mounting a tool, a CPU of a numerical control device moves a main shaft 7 from an ATC position C to an ATC preparation position B in a Y-axis minus direction, and then, moves respectively in an X-axis direction, a Y-axis plus direction, and a Z-axis plus direction toward a second return position A2 located in the Z-axis plus direction of a processing start position Q2. In a movement in the Y-axis minus direction, the CPU outputs a move command from the ATC position C to the ATC preparation position B by distribution and then outputs a move command toward the second return position A2. In movements in the Z-axis minus direction and the X-axis direction, as soon as the main shaft 7 reaches the ATC preparation position B position in a Y-axis direction, the CPU outputs a move command toward the second return position A2. Thereby in the movement in the Y-axis minus direction, the main shaft 7 can move from the ATC preparation position C to the second return position A2 without decelerating at the ATC preparation position B.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a numerical control device, a control method, a program, and a storage medium.

Background Art

[0002] The machine tool described in Patent Document 1 is horizontal, and the axial direction of the spindle is the horizontal direction. When performing tool change, after moving the spindle from the start position to the return position so that the tool does not collide with the workpiece and the jig, it moves to the machine origin and then to the preparation position. The start position is the position of the spindle at the end of machining of the workpiece. The return position is the position of the spindle where the tool does not collide with the workpiece and the jig. The machine origin is the position where the machine coordinates of the spindle in the axial direction are the origin dimension, and the machine coordinates of the spindle in the direction orthogonal to the axial direction are 0. The position of the origin dimension in the axial direction is the position where the spindle escapes maximally in the axial direction and is determined according to the structure of the machine tool. The preparation position is the position where the spindle is arranged for preparing to grip the tool holder holding the tool by the grip arm of the magazine.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the spindle once moves from the return position to the machine origin and then moves to the preparation position, there is a problem that the tool change time becomes long.

[0005] An object of the present invention is to provide a numerical control device, a control method, a program, and a storage medium capable of shortening the tool change time.

Means for Solving the Problems

[0006] According to a first aspect of the present invention, in a numerical control device for controlling a machine tool comprising a spindle for mounting a tool, a magazine having a plurality of storage compartments for storing tools, and a base for fixing a workpiece, the storage compartment of the magazine that stores an unmounted tool, which is a tool to be used for the next machining operation, is positioned such that, with the spindle positioned at a receiving position corresponding to the receiving position for the unmounted tool, it is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position and is a waiting position where the spindle waits before mounting the unmounted tool; it is located in the axial direction relative to the starting position, which is the position of the spindle at the start of machining the workpiece with the unmounted tool, and the unmounted tool does not collide with the workpiece; and it is located between the returning position and the receiving position and is located away from the receiving position in a first orthogonal direction perpendicular to the axial direction, and the preparation position is moved from the waiting position, through the receiving position and the preparation position in that order via the spindle, and then to the starting position. A numerical control device is provided, comprising a control unit, wherein the machine tool includes at least a position detection unit for detecting the position of the spindle in the first orthogonal direction, the mounting control unit comprising a first instruction unit for instructing the movement of the spindle from the receiving position to the preparation position in the first orthogonal direction, a second instruction unit for instructing the movement of the spindle from the preparation position to the return position in the first orthogonal direction, a third instruction unit for instructing the movement of the spindle from the preparation position to the return position in the axial direction and the movement of the spindle from the preparation position to the return position in a second orthogonal direction perpendicular to the first orthogonal direction, and a first determination unit for determining whether the spindle has reached the preparation position in the first orthogonal direction based on the detection result of the position detection unit, the second instruction unit starts outputting instructions as soon as the output of instructions by the first instruction unit is completed, and the third instruction unit starts outputting instructions as soon as the first determination unit determines that the spindle has reached the preparation position in the first orthogonal direction.

[0007] In the movement of the spindle in the first orthogonal direction, when an instruction is output by the first instruction unit, the spindle starts accelerating from zero towards the preparation position. When the instruction output is complete, it usually starts decelerating so that it stops moving at the preparation position. On the other hand, in this invention, the instruction output by the second instruction unit is performed as soon as the instruction output by the first instruction unit is completed. That is, the instruction from the first instruction unit and the instruction from the second instruction unit are output consecutively. Therefore, the spindle does not decelerate its movement speed towards the preparation position and continues moving towards the next return position. For example, compared to the case where the instruction from the second instruction unit is output only after the instruction output from the first instruction unit is completed and the spindle has reached the preparation position, confirmed by an in-position check, the spindle can move from the receiving position to the return position in the first orthogonal direction more quickly. Therefore, the numerical control device can shorten the tool change time.

[0008] The position detection unit of the machine tool in the first embodiment further detects the position of the spindle in the second orthogonal direction, and the mounting control unit further includes a fourth instruction unit that instructs the movement of the spindle from the return position to the start position in the axial direction, and a second determination unit that determines whether the spindle has reached the return position in the first orthogonal direction and the second orthogonal direction based on the detection result of the position detection unit, and the output of an instruction by the fourth instruction unit may be started as soon as the output of an instruction by the third instruction unit is completed and the second determination unit determines that the spindle has reached the return position in the first orthogonal direction and the second orthogonal direction.

[0009] In the axial movement of the spindle and the second orthogonal direction, when an instruction is output by the third instruction unit, the spindle starts accelerating from zero towards the return position, and when the instruction output is complete, it usually starts decelerating so as to stop moving at the return position. On the other hand, in the present invention, the instruction output by the fourth instruction unit is performed immediately when the instruction output by the third instruction unit is complete, provided that the spindle has reached the return position in the first orthogonal direction and the second orthogonal direction. That is, the instruction from the third instruction unit and the instruction from the fourth instruction unit are output consecutively as long as the spindle has reached the return position in the first orthogonal direction and the second orthogonal direction. Therefore, the spindle does not decelerate its movement speed toward the return position and continues moving toward the next starting position. For example, compared to the case where the instruction from the fourth instruction unit is output only after the instruction output by the third instruction unit is complete and the spindle has reached the return position is confirmed by an in-position check, the spindle can move from the preparation position to the starting position more quickly in the axial and second orthogonal directions. Therefore, numerical control devices can reduce tool change time.

[0010] According to a second aspect of the present invention, in order to control a machine tool comprising a spindle for mounting a tool, a magazine having a plurality of storage compartments for storing tools, and a stand for fixing a workpiece, the mounting control step includes moving the storage compartment of the magazine, which stores an unmounted tool that will be used for the next machining operation, from the waiting position, via the spindle in the order of the receiving position, the receiving position, and the preparation position, to the starting position, while the spindle is positioned at a position corresponding to the receiving position for receiving the unmounted tool. The storage compartment is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position, and is a position where the spindle waits before mounting the unmounted tool. The waiting position is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position, and is a position where the spindle waits before mounting the unmounted tool. The return position is located in a position away from the spindle along the axial direction of the spindle relative to the starting position, and is a position where the unmounted tool does not collide with the workpiece. The preparation position is located between the return position and the receiving position, and is a position away from the receiving position in a first orthogonal direction perpendicular to the axial direction. In a control method for a control device, the mounting control step comprises: a first determination step, which determines whether the spindle has reached the preparation position in the first orthogonal direction based on the detection result of a position detection unit provided in the machine tool that detects the position of the spindle in at least the first orthogonal direction; a first instruction step, which instructs the movement of the spindle from the receiving position to the preparation position in the first orthogonal direction; a second instruction step, which instructs the movement of the spindle from the preparation position to the return position in the first orthogonal direction; and a third instruction step, which instructs the movement of the spindle from the preparation position to the return position in the axial direction, and the movement of the spindle from the preparation position to the return position in a second orthogonal direction perpendicular to the first orthogonal direction. The control method is characterized in that, as soon as the output of the instruction by the first instruction step is completed, the output of the instruction by the second instruction step is started, and as soon as the first determination step determines that the spindle has reached the preparation position in the first orthogonal direction, the output of the instruction by the third instruction step is started. Therefore, the second embodiment has the same effects as the first embodiment.

[0011] According to a third aspect of the present invention, a program for controlling a machine tool comprising a spindle for mounting a tool, a magazine having a plurality of storage compartments for storing tools, and a stand for fixing a workpiece, wherein, with the spindle positioned at a location corresponding to a receiving position for receiving the unmounted tool, the storage compartment for storing an unmounted tool, which is a tool to be used for the next machining operation, is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position, and is a waiting position where the spindle waits before mounting the unmounted tool; a return position where the spindle is located in the axial direction relative to the starting position, which is the position of the spindle at the start of machining the workpiece with the unmounted tool, and the unmounted tool does not collide with the workpiece; and a preparation position where the spindle is located between the return position and the receiving position, and is located away from the receiving position in a first orthogonal direction perpendicular to the axial direction, moves from the waiting position, through the receiving position and the preparation position in that order, via the spindle, to the starting position, and then to the starting position, The provided program causes the computer to perform the following steps in the mounting control step: a first determination step, which determines whether the spindle has reached the preparation position in the first orthogonal direction based on the detection result of a position detection unit provided in the machine tool that detects the position of the spindle in at least in the first orthogonal direction; a first instruction step, which instructs the movement of the spindle from the receiving position to the preparation position in the first orthogonal direction; a second instruction step, which instructs the movement of the spindle from the preparation position to the return position in the first orthogonal direction; and a third instruction step, which instructs the movement of the spindle from the preparation position to the return position in the axial direction and the movement of the spindle from the preparation position to the return position in a second orthogonal direction perpendicular to the first orthogonal direction; and as soon as the output of the instruction by the first instruction step is completed, the output of the instruction by the second instruction step is started, and as soon as the first determination step determines that the spindle has reached the preparation position in the first orthogonal direction, the output of the instruction by the third instruction step is started. Therefore, the third embodiment has the same effect as the first embodiment.

[0012] According to a fourth aspect of the present invention, a program for causing a computer to execute a mounting control step in which, in order of the spindle, the computer moves from the waiting position, the receiving position, the preparation position, and then to the starting position, to the starting position, while the spindle is positioned at a position corresponding to the receiving position for receiving the unmounted tool, the waiting position is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position, and is a position where the spindle waits before mounting the unmounted tool, the starting position is located in the axial direction relative to the starting position which is the position of the spindle at the start of machining the workpiece with the unmounted tool, and the unmounted tool does not collide with the workpiece, and the preparation position is located between the returning position and the receiving position, and is located away from the receiving position in a first orthogonal direction perpendicular to the axial direction, the computer moves from the waiting position, the receiving position, the preparation position, and then to the starting position, the computer is positioned at the receiving position which corresponds to the receiving position for receiving the unmounted tool, and is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position, and is a position where the spindle waits before mounting the unmounted tool, the returning position is located in the axial direction relative to the starting position which is the position of the spindle at the start of machining the workpiece with the unmounted tool, and the preparation position is located between the returning position and the receiving position, and is located away from the receiving position in a first orthogonal direction perpendicular to the axial direction. The present invention provides a storage medium that stores a program which, in the mounting control step, causes the computer to execute: a first determination step which determines whether the spindle has reached the preparation position in the first orthogonal direction based on the detection result of a position detection unit provided in the machine tool that detects the position of the spindle in at least in the first orthogonal direction; a first instruction step which instructs the movement of the spindle from the receiving position to the preparation position in the first orthogonal direction; a second instruction step which instructs the movement of the spindle from the preparation position to the return position in the first orthogonal direction; and a third instruction step which instructs the movement of the spindle from the preparation position to the return position in the axial direction and the movement of the spindle from the preparation position to the return position in a second orthogonal direction perpendicular to the first orthogonal direction; and as soon as the output of the instruction by the first instruction step is completed, the output of the instruction by the second instruction step is started, and as soon as the first determination step determines that the spindle has reached the preparation position in the first orthogonal direction, the output of the instruction by the third instruction step is started. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view of machine tool 1, seen from the front and upper right. [Figure 2] This is a perspective view of machine tool 1, seen from the front right and lower. [Figure 3] This is a perspective view of machine tool 1 (magazine cover omitted) seen from the upper right rear. [Figure 4] This is a right side view of machine tool 1 (magazine cover omitted). [Figure 5] A diagram showing the forward path of ATC operation. [Figure 6] A diagram showing the return path of ATC operation. [Figure 7] This is a block diagram showing the electrical configuration of machine tool 1. [Figure 8] This is a flowchart of the NC control process. [Figure 9] This is a flowchart of the outbound execution process. [Figure 10] This is a continuation of the flowchart for the outbound execution process. [Figure 11] This is a flowchart of the return-path execution process. [Figure 12] This is a continuation of the flowchart for the return execution process. [Modes for carrying out the invention]

[0014] One embodiment of the present invention will be described. The following description will use the left / right, front / back, and up / down directions indicated by arrows in the figure. The left / right direction, up / down direction, and front / back direction of the machine tool 1 are the X-axis direction, Y-axis direction, and Z-axis direction of the machine tool 1, respectively. The machine tool 1 shown in Figure 1 is a horizontal type with a spindle 7 extending in the front / back direction (Z-axis direction), and a column 5 that moves in the X-axis direction and Z-axis direction, and is a column traverse type machine tool.

[0015] Referring to FIGS. 1 to 4, the structure of the machine tool 1 will be described. The machine tool 1 includes a base 2, a column 5, an X-axis moving mechanism 11, a Z-axis moving mechanism 12, a Y-axis moving mechanism 13, a spindle head 6, a spindle 7 (see FIG. 2), a control box 8, a rotary table 9, an ATC device 30 (see FIG. 3), a magazine cover 10, etc.

[0016] The base 2 is a substantially rectangular parallelepiped-shaped iron base that is long in the Z-axis direction. The X-axis moving mechanism 11 is provided at the rear part of the upper surface of the base 2 and supports the moving body 15 so as to be movable in the X-axis direction. The Z-axis moving mechanism 12 is provided on the upper surface of the moving body 15. The Z-axis moving mechanism 12 supports the column 5 so as to be movable in the Z-axis direction. The column 5 is a vertical column that extends in the vertical direction. The column 5 has a vertically long rectangular through-hole 5A (see FIG. 3) on the front surface. The through-hole 5A penetrates the column 5 in the front-rear direction. The frame cover 20 is attached to the front surface of the column 5. The frame cover 20 is a frame body having a vertically long rectangular shape in a front view and covers the space between the column 5 and the spindle head 6. The Y-axis moving mechanism 13 is provided on the front surface of the column 5 and supports the spindle head 6 so as to be movable in the Y-axis direction. The X-axis moving mechanism 11, the Z-axis moving mechanism 12, and the Y-axis moving mechanism 13 include, for example, guides, ball screws, and motors (X-axis motor 11A, Z-axis motor 12A, Y-axis motor 13A), and move the moving body 15, the column 5, and the spindle head 6 along the guides by the power of these motors, respectively.

[0017] The spindle head 6 extends in the Z-axis direction and is provided so as to be movable in the Y-axis direction along the front surface of the column 5 by the Y-axis moving mechanism 13. The spindle head 6 is movable between the machining area and the ATC area (see FIGS. 4 and 5) in the Y-axis direction. The machining area is provided in the space on the base 2 side (lower side) than the Y-axis origin. The Y-axis origin is the position where the machine coordinates of the Y-axis are 0. The ATC area is provided in the space on the opposite side (upper side) of the machining area with respect to the Y-axis origin. The machining area is an area for machining the workpiece W (see FIG. 5) fixed to the rotary table 9. The ATC area is an area for tool change by the ATC device 30. The ATC area is provided above the machining area in the Y-axis direction and at a position overlapping the machining area in the Z-axis direction.

[0018] The spindle head 6 is equipped with an upper cover 28 and a protective cover 85. The upper cover 28 is fixed to the rear end of the upper surface of the spindle head 6. The upper cover 28 is a metal plate that is roughly rectangular in shape when viewed from the front, and extends upward from the rear end of the upper surface of the spindle head 6. The protective cover 85 is fixed in a suspended state to the rear end of the lower surface of the spindle head 6. The protective cover 85 is equipped with multiple metal plates arranged vertically and extends and retracts telescopically in the vertical direction. The upper cover 28 moves up and down together with the spindle head 6, so as to constantly cover the area above the spindle head 6 on the front of the column 5. The protective cover 85 extends and retracts vertically in accordance with the vertical movement of the spindle head 6, so as to constantly cover the area below the spindle head 6 on the front of the column 5.

[0019] The spindle 7 is mounted coaxially with the spindle head 6 within the spindle head 6. The spindle head 6 rotatably supports the spindle 7. A motor holder box 27 (see Figure 3) is fixed to the rear of the spindle head 6. The motor holder box 27 extends rearward from the rear of the spindle head 6 and holds the spindle motor 26 inside. The motor holder box 27 protrudes rearward from the through-hole 5A of the column 5. The output shaft of the spindle motor 26 (see Figure 7) extends forward and is connected coaxially with the rear end of the spindle 7.

[0020] The spindle 7 is equipped with a tool mounting hole 40 and a holder holding member 19 (see Figure 5). The tool mounting hole 40 is located at the tip (front end) of the spindle 7. The tool mounting hole 40 is a substantially conical tool mounting hole that widens towards the tip of the spindle 7. The holder holding member 19 is located behind the tool mounting hole 40. A tool holder 90 (see Figure 5) is detachably mounted in the tool mounting hole 40. The tool holder 90 holds a tool 91 at one end and has a tapered portion and a pull stud 93 (see Figure 5) at the other end. The tapered portion is substantially conical and fits tightly into the tool mounting hole 40 of the spindle 7. The pull stud 93 protrudes axially from the top of the tapered portion. When the tapered portion is mounted in the tool mounting hole 40, the holder holding member 19 holds the pull stud 93 and fixes the tool holder 90 to the spindle 7.

[0021] A pair of support members 17 and 18 are provided at the rear of the base 2. The support members 17 and 18 are spaced apart from each other in the left-right direction and extend upward, supporting the control box 8 from below. The control box 8 houses a control panel (not shown). The control panel controls the operation of the machine tool 1. A fixed base 16 is provided on the front upper surface of the base 2. The rotary table 9 is fixed to the fixed base 16. The rotary table 9 is located in front of the spindle head 6. The rotary table 9 can rotate 360° around a rotation axis parallel to the Y-axis direction, with a workpiece W (see Figure 5) fixed to its upper surface with a jig (not shown).

[0022] A pair of support columns 21 and 22 are provided on the front upper surface of the base 2, on both the left and right sides. As shown in Figure 3, a connecting plate 23 is fixed between the upper parts of the support columns 21 and 22, which are opposite each other. The ATC device 30 is fixed to the front of the connecting plate 23. Therefore, the ATC device 30 is positioned between the column 5 and the rotary table 9 and above the spindle head 6 by the support columns 21 and 22. The ATC device 30 includes a tool magazine 31, a reducer 32, a magazine motor 33, etc. The tool magazine 31 includes a magazine base 37 and a number of grip arms 35. The magazine base 37 is roughly disc-shaped and is rotatably supported on the front of the connecting plate 23 around a single axis parallel to the Z-axis direction. The reducer 32 and the magazine motor 33 are attached to the tool magazine 31. The output shaft (not shown) of the magazine motor 33 is connected to the rotation shaft (not shown) of the magazine base 37 via the reducer 32. The power of the magazine motor 33 is transmitted to the rotating shaft of the magazine base 37 via the reduction gear 32. Multiple grip arms 35 are arranged along the outer circumference of the magazine base 37 and extend radially outward. The tips of the grip arms 35 grip the tool holder 90 from the Y-axis direction perpendicular to the tool holder 90 when the tool holder 90 is lying horizontally. The shape of the grip arms 35 is not particularly limited, and any configuration that can grip the tool holder 90 is acceptable. The grip arms 35 that perform tool changes with the spindle 7 move to the ATC position C (see Figure 5) of the tool magazine 31. The ATC position C is the lowest position of the tool magazine 31.

[0023] As shown in Figures 1 and 2, a magazine cover 10 is fixed to the front of the upper part of each of the support columns 21 and 22. The magazine cover 10 is box-shaped and covers the perimeter of the tool magazine 31. The magazine cover 10 prevents chips and cutting fluid splashes from adhering to the tool magazine 31. An opening 102 is provided in the bottom wall 101 of the magazine cover 10. The opening 102 is rectangular in bottom view and is located directly below the ATC position C, which is the lowest point of the tool magazine 31. A shutter 103 is provided in the opening 102. The shutter 103 opens and closes the opening 102 under control from the control panel. When the shutter 103 is open, the spindle 7 can pass through the opening 102 and move to the ATC position C.

[0024] Referring to Figures 5 and 6, the outline of the tool change operation will be explained. In the machining state when the machine tool 1 is cutting the workpiece W, the spindle 7 is located in the machining area. After machining with the tool 91 mounted on the spindle 7 is completed, the machine tool 1 performs a tool change operation. The tool change operation includes a tool storage operation in which the used tool 91 is stored in the tool magazine 31, and a tool mounting operation in which the next tool to be used, 92, is mounted on the spindle 7 and moved to the position where machining will begin. The path the spindle 7 moves when storing the tool is called the forward path, and the path it moves when mounting the tool is called the return path. In this embodiment, "moving the spindle 7" is synonymous with "moving the spindle head 6".

[0025] The forward path is the route by which the spindle 7 moves from the machining end position Q1 to the ATC origin position D (see Figure 5). The return path is the route by which the spindle 7 moves from the ATC origin position D to the machining start position Q2 (see Figure 6). The machining end position Q1 is the position of the spindle 7 when machining of the workpiece W is completed according to the NC program. The ATC origin position D is a reference point for tool changes provided in the ATC area, and is the position where the tool magazine 31 can rotate. The machining start position Q2 is the position of the spindle 7 when machining of the workpiece W is started according to the NC program, and is the target position to which the spindle 7 is moved after tool changes.

[0026] The forward journey will now be explained. As shown in Figure 5, the machine tool 1 moves the spindle 7 from the machining end position Q1 in the Z-axis direction, passing through the first return position A1 to the ATC preparation position B. The first return position A1 is set to be away from the machining end position Q1 in the Z-axis direction, so that the tool 91 mounted on the spindle 7 does not come into contact with the workpiece W and fixture fixed on the rotary table 9. The first return position A1 is at the same coordinates as the machining end position Q1 in the X-axis and Y-axis directions. The ATC preparation position B is at the same coordinates as the ATC position C. X-axis direction and These are the same coordinate positions in the Z-axis direction. ATC position C is the position where the grip arm 35 of the tool magazine 31 grips the tool holder 90 that holds the tool 91. ATC preparation position B is located away from ATC position C in the Y-axis direction, and is the position where the spindle 7 is positioned to perform gripping and releasing of the tool holder 90 by the grip arm 35 in the Y-axis direction. ru.

[0027] Next, the machine tool 1 raises the spindle 7 from the ATC preparation position B to the ATC position C. At this time, the empty grip arm 35 located directly below the tool magazine 31 is used to support the spindle 7. Tool holder 90 It engages from below. In this state, the machine tool 1 moves the spindle 7 backward from the ATC position C in the Z-axis direction to the ATC origin position D. , Lord From axis 7 Tool holder 90 It is then withdrawn. This completes the forward movement of the spindle 7 when the tool is stored.

[0028] Let's explain the return process. The machine tool 1 rotates the tool magazine 31 and positions the grip arm 35, which holds the next tool to be mounted 92, directly below the tool magazine 31. At this time, the next tool 92 is positioned in front of the spindle 7. In this state, as shown in Figure 6, the machine tool 1 moves the spindle 7, which is at the ATC origin position D, forward in the Z-axis direction to the ATC position C. As a result, the next tool 92 is mounted on the spindle 7.

[0029] When the next tool 92 is mounted on the spindle 7, the machine tool 1 lowers the spindle 7 from the ATC position C to the ATC preparation position B. Next, the machine tool 1 moves the spindle 7 from the ATC preparation position B to the second return position A2, and then moves it to the machining start position Q2. The second return position A2 is set to be away from the machining start position Q2 in the Z-axis direction, so that the tool 91 mounted on the spindle 7 does not come into contact with the workpiece W and fixture fixed on the rotary table 9. The second return position A2 is at the same coordinates as the machining start position Q2 in the X-axis and Y-axis directions. This completes the return movement of the spindle 7 during tool mounting, and the series of tool change operations is completed.

[0030] Referring to Figure 7, the electrical configuration of machine tool 1 will be described. Machine tool 1 includes a numerical control device 50, a spindle motor 26, an X-axis motor 11A, a Y-axis motor 13A, a Z-axis motor 12A, a magazine motor 33, a shutter motor 34, drive circuits 61-66, encoders 26A, 11B, 12B, 13B, 33A, 34A, an operation panel 25, and the like.

[0031] The numerical control device 50 includes a CPU 51, ROM 52, RAM 53, storage device 54, communication interface 55, input / output interface 56, etc. The CPU 51 provides overall control of the numerical control device 50. The ROM 52 stores various programs, such as NC control programs. The NC control program executes the NC control processing described later (see Figure 8). The RAM 53 stores various data during the execution of various processes. The storage device 54 is a non-volatile memory and stores various data, such as NC programs for machining. The communication interface 55 can be connected to a terminal (not shown) by wire or wireless. The input / output interface 56 connects the operation panel 25 and the drive circuits 61-66.

[0032] The spindle motor 26 rotates the spindle 7 with the tool attached. The X-axis motor 11A, Z-axis motor 12A, and Y-axis motor 13A move the workpiece W and the spindle 7 relative to each other in the X-axis, Z-axis, and Y-axis directions. The magazine motor 33 rotates the tool magazine 31. The shutter motor 34 opens and closes the shutter 103. The spindle motor 26, X-axis motor 11A, Z-axis motor 12A, Y-axis motor 13A, magazine motor 33, and shutter motor 34 are servo motors. The drive circuit 61 controls the spindle motor 26 based on a control signal from the CPU 51. The drive circuit 62 controls the X-axis motor 11A based on a control signal from the CPU 51. The drive circuit 63 controls the Z-axis motor 12A based on a control signal from the CPU 51. The drive circuit 64 controls the Y-axis motor 13A based on a control signal from the CPU 51. The drive circuit 65 controls the magazine motor 33 based on a control signal from the CPU 51. The drive circuit 66 controls the shutter motor 34 based on a control signal from the CPU 51.

[0033] Encoder 26A detects the rotational position of the spindle motor 26 and transmits the detection signal to the drive circuit 61. Based on the detection signal, the drive circuit 61 performs feedback control of the spindle motor 26 and outputs the rotation angle of the spindle 7 corresponding to the rotational position to the CPU 51. Encoder 11B detects the rotational position of the X-axis motor 11A and transmits the detection signal to the drive circuit 62. Based on the detection signal, the drive circuit 62 performs feedback control of the X-axis motor 11A and outputs the position of the spindle 7 in the X-axis direction corresponding to the rotational position to the CPU 51. Encoder 12B detects the rotational position of the Z-axis motor 12A and transmits the detection signal to the drive circuit 63. Based on the detection signal, the drive circuit 63 performs feedback control of the Z-axis motor 12A and outputs the position of the spindle 7 in the Z-axis direction corresponding to the rotational position to the CPU 51. Encoder 13B detects the rotational position of the Y-axis motor 13A and transmits the detection signal to the drive circuit 64. The drive circuit 64 performs feedback control of the Y-axis motor 13A based on the detection signal and outputs the position of the main shaft 7 in the Y-axis direction according to the rotation position to the CPU 51. The encoder 33A detects the rotation position of the magazine motor 33 and transmits the detection signal to the drive circuit 65. The drive circuit 65 performs feedback control of the magazine motor 33 based on the detection signal and outputs the open / closed state of the shutter 103 according to the rotation position to the CPU 51. The encoder 34A detects the rotation position of the shutter motor 34 and transmits the detection signal to the drive circuit 66. The drive circuit 66 performs feedback control of the shutter motor 34 based on the detection signal. The operation panel 25 allows for the display and input of various information.

[0034] This section explains the command format for tool change operations. Tool change operations can be set using control commands in the NC program. Command formats such as G100 and M06 can be used. The coordinate values ​​of the machining start position Q2, the Z-axis coordinate values ​​of the first return position A1 and the second return position A2 are included in the tool change command. Specific examples of G100 and M06 are as follows. ·G100T_L_X_Y_Z_R_ ·M06T_L_X_Y_Z_R_ T, L, X, Y, Z, and R are addresses. T is the tool number, pot number, or group number. L specifies the T modal value after G100. The T modal value indicates the tool number or pot number to be replaced in subsequent tool change commands. X, Y, and Z are the X, Y, and Z coordinate values ​​of the machining start position Q2. R is the Z-axis coordinate value of the first return position A1 and the second return position A2, which is the coordinate value of the position where the tool does not come into contact with the workpiece and fixture on the table. Furthermore, when positioning the spindle 7 to the first return position A1 and the second return position A2, the CPU 51 operates by applying a tool length offset. Tool length offset is the correction of the Z-axis coordinate value so that the tip of the tool becomes the reference point. The tool length offset value is, for example, the value obtained by pre-measuring the length in the Z-axis direction between the position of the tip of the tool and the position of the spindle 7 in the machine coordinates, with the tool held in the tool holder 90 and the tool holder 90 mounted on the spindle 7. The tool offset value may be specified by including it in the tool change command as described above, or it may be set in advance by the user as a parameter and stored in the storage device 54 in association with the tool number.

[0035] The NC control process will be explained with reference to Figures 8 to 12. The user selects an NC program on the operation panel 25. When the CPU 51 receives an operation to execute the NC program selected on the operation panel 25, it reads the NC control program from the ROM 52 and executes this process.

[0036] As shown in Figure 8, the CPU 51 reads the selected NC program from the storage device 54 (S11). The CPU 51 interprets one block from the first line of the read NC program (S12). The CPU 51 determines whether the control command of the interpreted block is M30 (end command) or not (S13). If the interpreted control command is not M30 (S13: NO), the CPU 51 determines whether the interpreted control command is G100 or M06 (S14). If it is neither G100 nor M06 (S14: NO), the CPU 51 executes the interpreted control command (S15). The CPU 51 moves to the next block (S19) and returns to S12 to repeat the above process. If the control command of the interpreted block is G100 or M06 (S14: YES), the CPU 51 executes the forward execution process.(S16) .

[0037] The forward execution process will be explained with reference to Figures 9 and 10. When the forward execution process is performed, the spindle 7 is positioned at the machining completion position Q1, where machining of the workpiece W has been completed. As shown in Figure 9, the CPU 51 calculates the coordinate value of the first return position A1 based on the Z-axis coordinate value of the first return position A1 included in the control command, the coordinate value of the machining completion position Q1, and the tool length offset value (S21). Based on the coordinate value of the machining completion position Q1 and the coordinate value of the first return position A1, the CPU 51 calculates a movement command to move the spindle 7 from the machining completion position Q1 to the first return position A1 (S22). When moving the spindle 7, the CPU 51 outputs a drive instruction as a movement command to the servo motors, namely the X-axis motor 11A, Z-axis motor 12A, and Y-axis motor 13A, at each sampling period. When the servo motor receives a movement command, it starts accelerating, accelerates while the movement command continues, maintains the maximum speed once it reaches it, and when the movement command ends, starts decelerating using a moving average filter, and stops after deceleration. Therefore, the travel distance of the spindle 7 must be calculated taking into account the acceleration and deceleration of the servo motor. The CPU 51 calculates the number of sampling periods for which it continues to output the movement command so that the distance the spindle 7 travels while the servo motor is accelerating, driving at maximum speed, and then decelerating and stopping matches the distance between the machining end position Q1 and the first return position A1. The CPU 51 distributes and generates the movement command from the machining end position Q1 to the first return position A1 for the calculated number of periods.

[0038] The first return position A1 is in the Z-axis + direction relative to the machining end position Q1. The CPU 51 executes the processes S24 to S27 until it has finished outputting all the distributed movement commands (S23: NO). The CPU 51 outputs a command to open the shutter 103. This command is output only on the first execution. The shutter motor 34 is driven and starts opening the shutter 103 (S24). The CPU 51 outputs a command to start orienting. This command is output only on the first execution. The spindle motor 26 is driven and starts rotating the spindle 7, directing its rotational position toward the orient position (S26). The orient position is the position where the rotational position of the spindle 7 is 0° or 180°, and the orientation of the spindle 7 and the tool 91 is positioned when the tool holder 90 is mounted in the tool mounting hole 40 of the spindle 7. Orient refers to the operation of rotating the main spindle 7 and aligning the rotational position (rotation angle) of the main spindle 7 with the orient position. The CPU 51 performs the operation every sampling period. to Z The CPU outputs movement commands distributed in the axial direction (S27). The spindle 7 moves from the machining start position Q2 in the Z-axis direction and begins to reverse to the first return position A1. When the CPU 51 has finished outputting all the distributed movement commands (S23: YES), it proceeds to S28. The spindle 7 is moving to the first return position A1, and since the distribution of movement commands is complete, it is just before the deceleration of the movement speed begins.

[0039] CPU 51 calculates the coordinate values ​​of ATC preparation position B (S28). The coordinate values ​​of ATC preparation position B are predetermined default coordinate values. and Equipment-specific parameters from The CPU 51 calculates a movement command to move the spindle 7 from the first return position A1 to the ATC preparation position B based on the coordinate values ​​of the first return position A1 and the ATC preparation position B (S29). The CPU 51 distributes and generates movement commands in the X, Z, and Y axes so that the distance the spindle 7 moves, taking into account acceleration and deceleration, matches the distance between the first return position A1 and the ATC preparation position B.

[0040] The CPU 51 executes processes S32 to S34 until it has finished outputting all movement commands distributed in the X, Z, and Y directions (S31: NO). The CPU 51 outputs the movement commands distributed in the Z direction at each sampling period. Out (S32). As a result, the command to move from the first return position A1 to the ATC preparation position B in the Z-axis direction is output continuously following the command to move from the machining end position Q1 in the Z-axis direction to the first return position A1, which has just been distributed. The spindle 7 maintains its maximum speed and continues moving toward the ATC preparation position B without starting to decelerate its movement speed toward the first return position A1. In other words, the spindle 7 continues moving from the machining end position Q1 to the ATC preparation position B in the Z-axis direction without performing an in-position check at the first return position A1.

[0041] The output of movement commands in the Z-axis direction begins before the spindle 7 passes the first return position A1 in the Z-axis direction (S33: NO). The position of the spindle 7 in the X, Z, and Y axes is constantly monitored based on feedback control of the drive circuits 62-64 by encoders 11B, 12B, and 13B. When the spindle 7 passes the first return position A1 in the Z-axis direction (S33: YES), the CPU 51 distributes the movement commands in the X and Y axes at each sampling period. Out The CPU 51 completes the output of all movement commands distributed in the X, Z, and Y directions (S31: YES) and proceeds to S41. The spindle 7 is moving to the ATC preparation position B, and in particular, in the Y direction, the distribution of movement commands has been completed, so it is just before the deceleration of the movement speed begins.

[0042] As shown in Figure 10, the CPU 51 calculates the coordinate values ​​of ATC position C (S41). The coordinate values ​​of ATC position C are predetermined default coordinate values. and Equipment-specific parameters fromThe CPU 51 calculates a movement command to move the spindle 7 from ATC preparation position B to ATC position C based on the coordinate values ​​of ATC preparation position B and ATC position C (S42). ATC position C is in the Y-axis+ direction relative to ATC preparation position B. The CPU 51 distributes and generates movement commands in the Y-axis direction so that the movement distance of the spindle 7, taking acceleration and deceleration into consideration, matches the distance between ATC preparation position B and ATC position C.

[0043] The CPU 51 executes processes S44 to S49 until it has completed outputting all distributed movement commands (S43:NO). If the CPU 51 determines, based on feedback control, that the spindle 7 has not reached the ATC preparation position B in the Z-axis direction (S44:NO), it returns to process S43. If the CPU 51 determines, based on feedback control, that the spindle 7 has not reached the ATC preparation position B in the X-axis direction (S46:NO), it returns to process S43. If the CPU 51 determines, based on feedback control, that the shutter 103 has not been opened (S47:NO), it returns to process S43. If the CPU 51 determines, based on feedback control, that the rotation position of the spindle 7 is not the orient position (S48:NO), it returns to process S43.

[0044] When the spindle 7 has reached the ATC preparation position B in the Z-axis and X-axis directions (S44:YES, S46:YES), the shutter 103 is open (S47:YES), and the spindle 7 is in the orient position (S48:YES), the CPU 51 distributes the movement command in the Y-axis direction at each sampling period. OutThe process is executed (S49). Here, if the spindle 7 has reached the ATC preparation position B in the Z-axis and X-axis directions and is in the orient position before reaching the ATC preparation position B in the Y-axis direction, and the shutter 103 is open, then the command to move from the ATC preparation position B to the ATC position C in the Y-axis direction is output consecutively following the command to move from the first return position A1 to the ATC preparation position B in the Y-axis direction. The spindle 7 maintains its maximum speed and continues moving toward the ATC position C without starting to decelerate its movement speed toward the ATC preparation position B in the Y-axis direction. That is, the spindle 7 continues moving from the first return position A1 to the ATC position C in the Y-axis direction without performing an in-position check at the ATC preparation position B. When the CPU 51 has finished outputting all the movement commands distributed in the Y-axis direction (S43:YES), it proceeds to S51.

[0045] The CPU 51 moves the spindle 7 from the ATC preparation position B in the Y-axis direction and raises it to the ATC position C. The ATC position C corresponds to the pot position (receiving position) of the grip arm 35 directly below the tool magazine 31. Therefore, as the spindle 7 rises to the ATC position C, the tool holder 90 that holds the tool 91 mounted on the spindle 7 engages with the empty pot from below.

[0046] CPU 51 calculates the coordinate values ​​of the ATC origin position D (S51). The coordinate values ​​of the ATC origin position D are predetermined default coordinate values. and Equipment-specific parameters from The CPU 51 calculates a movement command to move the spindle 7 from ATC position C to ATC origin position D based on the coordinate values ​​of ATC position C and ATC origin position D (S52). The ATC origin position D is in the Z-axis+ direction relative to ATC position C. The CPU 51 distributes and generates movement commands in the Z-axis direction so that the movement distance of the spindle 7, taking acceleration and deceleration into consideration, matches the distance between ATC position C and ATC origin position D.

[0047] The CPU 51 executes processes S54 to S56 until it has finished outputting all the distributed movement commands (S53: NO). Based on the feedback control, if the CPU 51 determines that the spindle 7 has not reached the ATC position C in the Y-axis direction (S54: NO), it returns to process S53. If the spindle 7 has reached the ATC position C in the Y-axis direction (S54: YES), the CPU 51 distributes the distributed movement commands in the Z-axis direction at each sampling period. Out The CPU 51 completes the output of all movement commands distributed in the Z-axis direction (S53:YES) and proceeds to S57. The tool holder 90 that holds the tool 91 is gripped by the grip arm 35 and is pulled out from the spindle 7 as the spindle 7 moves in the Z+ direction. Based on feedback control, the CPU 51 waits for the spindle 7 to reach the ATC origin position D in the Z-axis direction (S57:NO), and once it reaches it (S57:YES), it terminates the forward execution process.

[0048] Returning to the flow in Figure 8, the CPU 51 performs the process of preparing the next tool 92 to be mounted (S17). The machine tool 1 rotates the tool magazine 31 and positions the grip arm 35 that holds the next tool 92 directly below the tool magazine 31. Next, the CPU 51 performs the return process (S18).

[0049] The return-path execution process will be explained with reference to Figures 11 and 12. When the return-path execution process is performed, the spindle 7 is located at the ATC origin position D. As shown in Figure 11, the CPU 51 calculates the coordinate values ​​of the ATC position C (S61). Based on the calculated coordinate values, the CPU 51 calculates a movement command to move the spindle 7 from the ATC origin position D to the ATC position C (S62). The ATC position C is in the Z-axis direction relative to the ATC origin position D, and the CPU 51 distributes and generates movement commands in the Z-axis direction. The CPU 51 continues to output all distributed movement commands every sampling period until it has completed outputting all of them (S63:NO). to ZThe CPU 51 outputs the movement commands distributed in the axial direction (S64). Once the CPU 51 has finished outputting all the distributed movement commands (S63:YES), it waits for the spindle 7 to reach the ATC position C in the Z-axis direction based on feedback control (S66:NO).

[0050] When the spindle 7 reaches ATC position C in the Z-axis direction (S66:YES), the CPU 51 calculates the coordinate values ​​of ATC preparation position B (S67). Based on the calculated coordinate values, the CPU 51 calculates a movement command to move the spindle 7 from ATC position C to ATC preparation position B (S68). ATC preparation position B is in the Y-axis direction relative to ATC position C, and the CPU 51 distributes and generates movement commands in the Y-axis direction. The CPU 51 continues to generate the output of all distributed movement commands every sampling period until it has completed outputting all of them (S69:NO). Y The CPU 51 outputs the movement commands distributed in the axial direction (S71). Once the CPU 51 has finished outputting all the distributed movement commands (S69: YES), it proceeds to S81. The spindle 7 is moving to the ATC preparation position B in the Y-axis direction, and since the distribution of movement commands is complete, it is just before the deceleration of the movement speed begins.

[0051] As shown in Figure 12, the CPU 51 calculates the coordinates of the second return position A2 based on the Z-axis coordinates of the second return position A2 included in the control command, the coordinates of the machining start position Q2, and the tool length offset value (S81). Based on the calculated coordinates, the CPU 51 calculates a movement command to move the spindle 7 from the ATC preparation position B to the second return position A2 (S82). The CPU 51 distributes and generates movement commands in the X-axis, Z-axis, and Y-axis directions respectively so that the distance the spindle 7 moves, taking into account acceleration and deceleration, matches the distance between the ATC preparation position B and the second return position A2.

[0052] The CPU 51 executes processes S84 to S88 until it has finished outputting all movement commands distributed in the X, Z, and Y directions (S83: NO). The CPU 51 processes the movement commands distributed in the Y direction every sampling period. OutThe force is applied (S84). As a result, the movement command from the ATC preparation position B to the second return position A2 in the Y-axis direction is output continuously following the movement command from the ATC position C to the ATC preparation position B in the Y-axis direction, for which distribution has been completed. The spindle 7 maintains its maximum speed and continues moving toward the second return position A2 without starting to decelerate its movement speed toward the ATC preparation position B in the Y-axis direction. In other words, the spindle 7 continues moving from the ATC position C to the second return position A2 in the Z-axis direction without performing an in-position check at the ATC preparation position B.

[0053] The output of movement commands in the Y-axis direction begins before the spindle 7 passes the ATC preparation position B in the Y-axis direction (S86: NO). Based on feedback control, when the spindle 7 passes the ATC preparation position B in the Y-axis direction (S86: YES), the CPU 51 outputs a command to close the shutter 103. This command is output only on the first execution. The shutter motor 34 is driven and the shutter 103 begins to close (S87). The CPU 51 outputs the distributed movement commands in the X-axis and Z-axis directions at each sampling period. Out The CPU 51 completes the output of all movement commands distributed in the X, Z, and Y directions (S83: YES) and then proceeds to process the command. S92 The process continues. The main shaft 7 is moving to the second return position A2, and in particular, with respect to the Z-axis direction, the distribution of movement commands has been completed, so it is just before the deceleration of the movement speed begins. The CPU 51 calculates the coordinate values ​​of the machining start position Q2 (S92). The coordinate values ​​of the machining start position Q2 are included in the control command. Based on the coordinate values, the CPU 51 calculates a movement command to move the spindle 7 from the second return position A2 to the machining start position Q2 (S93). The machining start position Q2 is in the Z-axis direction relative to the second return position A2. The CPU 51 distributes and generates movement commands in the Z-axis direction so that the distance the spindle 7 moves, taking into account acceleration and deceleration, matches the distance between the second return position A2 and the machining start position Q2.

[0054] The CPU 51 executes processes S96 to S98 until it has completed outputting all distributed movement commands (S94: NO). If the CPU 51 determines, based on feedback control, that the spindle 7 has not reached the second return position A2 in the X-axis direction (S96: NO), it returns to process S94. If the CPU 51 determines, based on feedback control, that the spindle 7 has not reached the second return position A2 in the Y-axis direction (S97: NO), it returns to process S94.

[0055] When the spindle 7 has reached the second return position A2 in the X and Y directions (S96:YES, S97:YES), the CPU 51 distributes the movement command in the Z direction to each sampling period. Out The process is executed (S98). Here, if the spindle 7 has reached the second return position A2 in the X and Y directions before it has reached the second return position A2 in the Z direction, the command to move from the second return position A2 in the Z direction to the machining start position Q2 is output consecutively following the command to move from the ATC preparation position B to the second return position A2 in the Z direction. The spindle 7 maintains its maximum speed and continues moving towards the machining start position Q2 without starting to decelerate its movement speed toward the second return position A2 in the Z direction. In other words, the spindle 7 continues moving from the ATC preparation position B to the machining start position Q2 in the Z direction without performing an in-position check at the second return position A2. When the CPU 51 has finished outputting all the movement commands distributed in the Z direction (S94:YES), it proceeds to S99. Based on feedback control, the CPU 51 waits for the spindle 7 to reach the machining start position Q2 in the Z direction (S99:NO), and when it reaches it (S99:YES), it terminates the return process.

[0056] Returning to the flow in Figure 8, the CPU 51, having completed the series of tool change operations for G100, moves to the next block (S19) and interprets the next block (S12). If the next block interpreted is M30 (S13: YES), the CPU 51 terminates this process.

[0057] As explained above, when the spindle 7 moves in the Y-axis direction, if a movement command is output toward ATC preparation position B, the spindle 7 starts accelerating from 0 toward ATC preparation position B from ATC position C. Once the distribution of movement commands is complete, it usually starts decelerating so that it stops moving toward ATC preparation position B. The command to move towards the second return position A2 is output as soon as the command to move towards the ATC preparation position B is completed. That is, the command to move towards the ATC preparation position B and the command to move towards the second return position A2 are output consecutively. Therefore, the spindle 7 does not decelerate its movement speed towards the ATC preparation position B and continues moving towards the next second return position A2. For example, compared to a case where the command to move towards the second return position A2 is output only after the command to move towards the ATC preparation position B has been completed and the spindle 7 has reached the ATC preparation position B, the spindle 7 can move from the ATC position C to the second return position A2 faster in the Y-axis direction. Therefore, the numerical control device 50 can shorten the tool change time.

[0058] When the spindle 7 moves in the Z-axis direction, if a movement command toward the second return position A2 is output, the spindle 7 starts accelerating from 0 toward the second return position A2 from the ATC preparation position B. Once the command output is complete, it usually starts decelerating so that it stops moving at the second return position A2. The output of a movement command toward the machining start position Q2 is performed immediately when the output of the movement command toward the second return position A2 is complete, provided that the spindle 7 has reached the second return position A2 in both the Y-axis and X-axis directions. In other words, the movement command toward the second return position A2 and the movement command toward the machining start position Q2 are output consecutively as long as the spindle 7 has reached the second return position A2 in both the Y-axis and X-axis directions. Therefore, the spindle 7 does not decelerate its movement speed toward the second return position A2 and continues moving toward the next start position. For example, compared to a case where the command to move to the second return position A2 is output and the spindle 7 has reached the second return position A2 is confirmed by an in-position check before the command to move to the machining start position Q2 is output, the spindle 7 can move from the ATC preparation position B to the machining start position Q2 in the Z-axis direction more quickly. Therefore, the numerical control device 50 can shorten the tool change time.

[0059] In the above description, the grip arm 35 is an example of the "storage unit" of the present invention. The tool magazine 31 is an example of the "magazine" of the present invention. The next tool 92 is an example of the "unmounted tool" of the present invention. The ATC position C is an example of the "receiving position" of the present invention. The ATC origin position D is an example of the "standby position" of the present invention. The machining start position Q2 is an example of the "start position" of the present invention. The second return position A2 is an example of the "return position" of the present invention. The ATC preparation position B is an example of the "preparation position" of the present invention. The CPU 51 that executes the return process corresponds to the "mounting control unit" of the present invention. The Y-axis direction is an example of the "first orthogonal direction" of the present invention. In feedback control based on the detection signals of encoders 11B and 13B, the drive circuits 62 and 64 that output the position of the spindle 7 in the X-axis direction and the Y-axis direction according to the rotational position of the respective drive shafts of the X-axis motor 11A and Y-axis motor 13A to the numerical control device 50 are examples of the "position detection unit" of the present invention. The CPU 51 that executes the process in S71 is an example of the "first instruction unit" of the present invention. The CPU 51 that executes the process in S84 is an example of the "second instruction unit" of the present invention. The CPU 51 that executes the process in S88 is an example of the "third instruction unit" of the present invention. The CPU 51 that executes the process in S86 is an example of the "first decision unit" of the present invention. The CPU 51 that executes the process in S98 is an example of the "fourth instruction unit" of the present invention. The CPU 51 that executes the processes in S96 and S97 is an example of the "second decision unit" of the present invention.

[0060] The present invention is not limited to the above embodiments, and various modifications can be made. The machine tool 1 is a horizontal machine tool, but it may also be a vertical machine tool in which the axis direction of the spindle is vertical. The machine tool 1 moves the workpiece W and the tool 91 relative to the X, Y, and Z axes by moving the column 5 in the X-axis direction, the spindle 7 in the Z-axis direction, and the spindle 7 in the Y-axis direction, but other structures are also possible. For example, the column 5 may be moved in two axes, the X-axis direction and the Z-axis direction, and the spindle 7 may be moved in the Y-axis direction.

[0061] The Z-axis coordinate values ​​of the first return position A1 and the second return position A2 may not be included in the tool change command, but may be specified by user-configurable parameters. When positioning the spindle 7 to the first return position A1 and the second return position A2, the CPU 51 may operate without applying a tool length offset. The machine tool 1 opened and closed the shutter 103 of the magazine cover 10 by driving the shutter motor 34, but it may also be opened and closed by driving an air cylinder (not shown). In this case, the CPU 51 of the numerical control device 50 should perform a decision process in S47 based on the result of detecting the open / closed state of the shutter 103 with the open / closed sensor.

[0062] When CPU 51 outputs a command to move from the machining start position Q2 in the Z-axis direction to the first return position A1 in S27, it outputs a command to open the shutter 103 in S24, but it is not limited to this timing. For example, when CPU 51 outputs a command to move from the first return position A1 in the Z-axis direction to the ATC preparation position B in S32, it may also output a command to open the shutter 103. Alternatively, when CPU 51 outputs a command to move from the first return position A1 in the X-axis direction and the ATC preparation position B in S34, it may also output a command to open the shutter 103.

[0063] When CPU 51 outputs a command to move from the machining start position Q2 in the Z-axis direction to the first return position A1 in S27, it outputs a command to start orienting the spindle 7 in S26, but it is not limited to this timing. For example, when CPU 51 outputs a command to move from the first return position A1 in the Z-axis direction to the ATC preparation position B in S32, it may also output a command to start orienting the spindle 7. Alternatively, when CPU 51 outputs a command to move from the first return position A1 in the X-axis direction and the ATC preparation position B in S34, it may also output a command to start orienting the spindle 7. [Explanation of Symbols]

[0064] 1 Machine tools 7 Spindle 10 Magazine Covers 11B, 12B, 13B encoders 30 ATC device 31 Tool Magazine 35 Grip Arm 50 Numerical control device 51 CPU 92 Next tool A2 Second return position B ATC ready position C ATC position D ATC origin position Q2 Processing start position Double job

Claims

1. In a numerical control device for controlling a machine tool comprising a spindle for mounting tools, a magazine having multiple storage compartments for storing tools, and a base for fixing workpieces, The magazine includes a mounting control unit that, with the storage unit for storing an unmounted tool (a tool to be used for the next machining operation) among the multiple storage units of the magazine positioned at a location corresponding to the receiving position, moves the spindle from the standby position, through the receiving position and the preparation position in that order, and then moves it to the starting position. The receiving position is the position where the spindle receives the unmounted tool. The standby position is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position, and is a position in which the spindle waits before mounting the unmounted tool. The starting position is the position of the spindle at the start of machining the workpiece with the unmounted tool. The return position is a position that is separated from the starting position in the axial direction, and is a position where the unmounted tool does not collide with the workpiece. The aforementioned preparation position is a position located between the return position and the receiving position, and is separated from the receiving position in a first orthogonal direction perpendicular to the axial direction. The machine tool includes at least a position detection unit that detects the position of the spindle in the first orthogonal direction, The mounting control unit, A first instruction unit that instructs the movement of the main shaft from the receiving position to the preparation position in the first orthogonal direction, A second instruction unit that instructs the movement of the main shaft from the preparation position to the return position in the first orthogonal direction, A third instruction unit that instructs the movement of the main spindle from the preparation position to the return position in the axial direction, and the movement of the main spindle from the preparation position to the return position in a second orthogonal direction perpendicular to the first orthogonal direction, A first determination unit determines whether or not the main shaft has reached the preparation position in the first orthogonal direction based on the detection result of the position detection unit. Equipped with, Once the output of instructions by the first instruction unit is completed, the output of instructions by the second instruction unit will begin. As soon as the first determination unit determines that the main shaft has reached the preparation position in the first orthogonal direction, the third instruction unit starts outputting an instruction. A numerical control device characterized by the following.

2. The position detection unit of the machine tool further detects the position of the spindle in the second orthogonal direction, The mounting control unit, A fourth instruction unit that instructs the movement of the main shaft from the return position to the start position in the axial direction, A second determination unit determines, based on the detection result of the position detection unit, whether or not the main shaft has reached the return position in the first orthogonal direction and the second orthogonal direction. Furthermore, Once the output of the instruction by the third instruction unit is complete and the second determination unit determines that the main shaft has reached the return position in the first orthogonal direction and the second orthogonal direction, the output of the instruction by the fourth instruction unit begins. A numerical control device according to claim 1, characterized by the following:

3. To control a machine tool that includes a spindle for mounting tools, a magazine with multiple storage compartments for storing tools, and a stand for fixing workpieces, The magazine includes a mounting control step in which, with the storage compartment for storing an unmounted tool, which is a tool to be used for the next machining operation, among the multiple storage compartments of the magazine, is positioned at a location corresponding to the receiving position, the spindle is moved from the standby position, through the receiving position and the preparation position in that order, and then to the starting position. The receiving position is the position where the spindle receives the unmounted tool. The standby position is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position, and is a position in which the spindle waits before mounting the unmounted tool. The starting position is the position of the spindle at the start of machining the workpiece with the unmounted tool. The return position is a position that is separated from the starting position in the axial direction, and is a position where the unmounted tool does not collide with the workpiece. The aforementioned preparation position is a position located between the return position and the receiving position, and is separated from the receiving position in a first orthogonal direction perpendicular to the axial direction. In a control method for a numerical control device that mounts the unmounted tool to the spindle, The aforementioned mounting control step is, The machine tool is equipped with at least a position detection unit that detects the position of the spindle in the first orthogonal direction, and a first determination step is made to determine whether or not the spindle has reached the preparation position in the first orthogonal direction based on the detection result of the position detection unit, A first instruction step that instructs the movement of the main shaft from the receiving position to the preparation position in the first orthogonal direction, A second instruction step that instructs the movement of the main shaft from the preparation position to the return position in the first orthogonal direction, A third instruction step that instructs the movement of the main spindle from the preparation position to the return position in the axial direction, and the movement of the main spindle from the preparation position to the return position in a second orthogonal direction perpendicular to the first orthogonal direction, Equipped with, Once the output of the instruction in the first instruction step is completed, the output of the instruction in the second instruction step will begin. As soon as the first determination step determines that the main shaft has reached the preparation position in the first orthogonal direction, the output of the instruction by the third instruction step is initiated. A control method characterized by the following.

4. To control a machine tool that includes a spindle for mounting tools, a magazine with multiple storage compartments for storing tools, and a stand for fixing workpieces, In a program for operating a numerical control device that includes a mounting control step, in which, with the storage unit for storing an unmounted tool, which is a tool to be used for the next machining operation, among the multiple storage units of the magazine, is positioned at a position corresponding to the receiving position, the spindle is moved from the standby position, through the receiving position and the preparation position in that order, and then to the starting position, The receiving position is the position where the spindle receives the unmounted tool. The standby position is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position, and is a position in which the spindle waits before mounting the unmounted tool. The starting position is the position of the spindle at the start of machining the workpiece with the unmounted tool. The return position is a position that is separated from the starting position in the axial direction, and is a position where the unmounted tool does not collide with the workpiece. The aforementioned preparation position is a position located between the return position and the receiving position, and is separated from the receiving position in a first orthogonal direction perpendicular to the axial direction. On the computer, In the aforementioned mounting control step, The machine tool is equipped with at least a position detection unit that detects the position of the spindle in the first orthogonal direction, and a first determination step is made to determine whether or not the spindle has reached the preparation position in the first orthogonal direction based on the detection result of the position detection unit, A first instruction step that instructs the movement of the main shaft from the receiving position to the preparation position in the first orthogonal direction, A second instruction step that instructs the movement of the main shaft from the preparation position to the return position in the first orthogonal direction, A third instruction step that instructs the movement of the main spindle from the preparation position to the return position in the axial direction, and the movement of the main spindle from the preparation position to the return position in a second orthogonal direction perpendicular to the first orthogonal direction, Make it run, Once the output of the instruction in the first instruction step is completed, the output of the instruction in the second instruction step will begin. As soon as the first determination step determines that the main spindle has reached the preparation position in the first orthogonal direction, the output of the instruction by the third instruction step is initiated. A program characterized by the following.

5. To control a machine tool that includes a spindle for mounting tools, a magazine with multiple storage compartments for storing tools, and a stand for fixing workpieces, A program for causing a numerical control device to function, which causes a computer to execute a mounting control step in which, with the storage unit for storing an unmounted tool, which is a tool to be used for the next machining operation, among the plurality of storage units of the magazine, positioned at a location corresponding to the receiving position, the spindle is moved from the standby position, through the receiving position and the preparation position in that order, and then to the starting position, The receiving position is the position where the spindle receives the unmounted tool. The standby position is located in a direction away from the magazine along the axial direction of the spindle relative to the receiving position, and is a position in which the spindle waits before mounting the unmounted tool. The starting position is the position of the spindle at the start of machining the workpiece with the unmounted tool. The return position is a position that is separated from the starting position in the axial direction, and is a position where the unmounted tool does not collide with the workpiece. The aforementioned preparation position is a position located between the return position and the receiving position, and is separated from the receiving position in a first orthogonal direction perpendicular to the axial direction. On the computer, In the aforementioned mounting control step, The machine tool is equipped with at least a position detection unit that detects the position of the spindle in the first orthogonal direction, and a first determination step is made to determine whether or not the spindle has reached the preparation position in the first orthogonal direction based on the detection result of the position detection unit, A first instruction step that instructs the movement of the main shaft from the receiving position to the preparation position in the first orthogonal direction, A second instruction step that instructs the movement of the main shaft from the preparation position to the return position in the first orthogonal direction, A third instruction step that instructs the movement of the main spindle from the preparation position to the return position in the axial direction, and the movement of the main spindle from the preparation position to the return position in a second orthogonal direction perpendicular to the first orthogonal direction, Make it run, Once the output of the instruction in the first instruction step is completed, the output of the instruction in the second instruction step will begin. A program that, as soon as the first determination step determines that the main spindle has reached the preparation position in the first orthogonal direction, starts outputting an instruction by the third instruction step. A storage medium characterized by its ability to store data.

Images