JP7791985B2 - machine tools - Google Patents

Description

This disclosure relates to a technology for setting a transfer position for transferring work between a robot and a partner device.

Various technologies have been proposed for setting the transfer position for workpieces. For example, Patent Document 1 below describes an industrial robot that transfers workpieces between a table and itself. The industrial robot is an articulated robot that uses its hands to grasp and transport workpieces placed on the table. The table is equipped with a work measurement sensor that measures the length of the workpiece. The industrial robot inputs the measurement signal from the work measurement sensor, calculates the longitudinal center position of the workpiece, and sets the gripping position of the hand based on the calculated value.

Japanese Patent Application Publication No. 02-243285

In addition, adjustment of the robot's position is required not only when the robot receives the workpiece, but also when transferring the workpiece from the robot to a partner device such as a stand. Furthermore, there is a risk that the workpiece transfer control will not be able to execute with precision due to errors in the assembly accuracy of parts on the robot and the partner device. The industrial robot technology described above requires that a workpiece measurement sensor be installed on each partner device that receives the workpiece, which could complicate the entire system.

This disclosure has been made in consideration of the above-mentioned problems, and aims to provide a machine tool that can set the transfer position for handing over the workpiece to the other device based on measurement results while simplifying the device structure.

In order to solve the above-mentioned problems, this specification provides a robot including a contact detection device, a robot having a holding member and holding a workpiece with the holding member and transporting the workpiece, a counterpart device that receives the workpiece from the robot, and a control device, wherein the contact detection device outputs a contact detection signal in response to contact to the control device, the control device controls the robot to bring the contact detection device into contact with the counterpart device, acquires the contact detection signal from the contact detection device when contact with the counterpart device is detected, and performs a reference position setting process that sets the position of the robot at the time of contact as a reference position based on the acquisition of the contact detection signal, and a control device that takes the length of the workpiece as an input value. and executing a position setting process that sets a transfer position, which is a position of the robot when the workpiece having a length of the input value is transferred from the robot to the counterpart device, based on the acquired input value and the reference position, wherein the contact detection device is a touch probe that transmits the contact detection signal to the control device by wireless communication while being held by the holding member of the robot, and the control device sets the reference position based on the position of the robot at the timing when the contact detection device is brought into contact with the counterpart device and the contact detection signal is output from the contact detection device .

The present specification also provides a reference position control system for a robot having a holding member, which holds a workpiece with the holding member and transports the workpiece, a counterpart device that receives the workpiece from the robot, and a control device, wherein the robot is capable of holding a contact detection device with the holding member, the contact detection device outputs a contact detection signal in response to contact to the control device, the control device moves the robot with the contact detection device held by the holding member of the robot, brings the contact detection device into contact with the counterpart device, acquires the contact detection signal from the contact detection device when contact with the counterpart device is detected, and sets the position of the robot at the time of contact as a reference position based on the acquired contact detection signal. A machine tool is disclosed that executes a position setting process, and a position setting process that acquires the length of the workpiece as an input value and sets a transfer position, which is the position of the robot when transferring the workpiece of the length of the input value from the robot to the counterpart device, based on the acquired input value and the reference position, wherein the contact detection device is a touch probe that transmits the contact detection signal to the control device by wireless communication while held by the holding member of the robot, and the control device sets the reference position based on the position of the robot at the time when the contact detection signal is output from the contact detection device when the contact detection device is brought into contact with the counterpart device in the reference position setting process .

With the machine tool disclosed herein, the robot's contact detection device is brought into contact with a mating device, and the robot's reference position is set based on the contact detection signal generated at the time of contact. This makes it possible to set a reference position that takes into account errors in the assembly accuracy of parts on the robot and mating device. The control device then sets the transfer position when transferring the workpiece from the robot to the mating device based on an input value indicating the workpiece's length and the reference position. This eliminates the need to install sensors or the like on the mating device, simplifying the entire device while allowing the transfer position to be set with high accuracy based on measurement results.

FIG. 1 is a front view of a machine tool according to an embodiment of the present invention. Block diagram of a machine tool. FIG. 2 is a perspective view showing a main body of the machine tool with the device cover removed. FIG. 4 is a right side view of the machine tool in the state shown in FIG. 3 . FIG. 10A and 10B are diagrams showing the state of the left spindle device and the head when setting the reference position and when transferring the workpiece. FIG. 10 is a diagram showing a reception screen of the operation panel. 10A and 10B are diagrams showing the state of the stocker device and the head when the reference position is set and when the workpiece is transferred.

An embodiment of the machine tool disclosed herein will be described in detail below with reference to the drawings. FIG. 1 shows a front view of the machine tool 1 of this embodiment. FIG. 2 shows a block diagram of the machine tool 1. FIG. 3 shows a perspective view of the main body of the machine tool 1 with the equipment cover 2 (see FIG. 1) removed. In the following description, the direction of the machine tool 1 viewed from the front, as shown in FIG. 1, will be used as the reference, and the rightward direction in the machine width direction and parallel to the equipment installation surface will be referred to as the Z direction, the forward direction parallel to the equipment installation surface and perpendicular to the Z direction will be referred to as the Y direction, and the upward direction perpendicular to the Z direction and Y direction will be referred to as the X direction. Furthermore, in the following description, the letter "L" will generally be added to the reference numerals for equipment located on the left side of the machine tool 1, and the letter "R" will be added to the reference numerals for equipment located on the right side.

(Configuration of machine tool 1)
1 and 2, the front of machine tool 1 is covered by equipment cover 2, and a movable operation panel 3 is provided on the front of the machine. The operation panel 3 is movable in the Z direction from the center of the front of the machine to the right edge along a rail 6 provided on the lower right of the front of equipment cover 2. The equipment cover 2 is provided with a left front door 5L on the left side of the machine tool 1 and a right front door 5R on the right side. The left and right front doors 5L, 5R are, for example, sliding doors, and opening the doors allows access to the machining space behind the doors.

As shown in Figures 1 to 3, the machine tool 1 includes a control panel 3, a left-side machining device 11L, a right-side machining device 11R, a stocker device 9, a workpiece transport device 14, and a control device 15. A machining space for the left-side machining device 11L is provided behind the left-side front door 5L. The left-side machining device 11L is, for example, a turret-type lathe, and includes a left-side spindle unit 12L and a left-side turret 13L. The left-side spindle unit 12L, for example, includes multiple sub-jaws for chucking a workpiece. The multiple sub-jaws grip the workpiece and rotate the workpiece around a spindle parallel to the Z direction. The left-side turret 13L has a tool post to which multiple tools (rotary tools and cutting tools) can be attached, and performs tool indexing. The left-side turret 13L performs machining (such as cutting or drilling) on the workpiece held by the left-side spindle unit 12L using the indexed tools. A user can check the machining status of the workpiece and replace worn tools through the left-side front door 5L.

The right-side machining unit 11R has the same configuration as the left-side machining unit 11L, except for the orientation of the spindle (unit). Therefore, the description of the right-side machining unit 11R will omit the same details as the left-side machining unit 11L. Behind the right-side front door 5R, a machining space for the right-side spindle unit 12R and right-side turret 13R of the right-side machining unit 11R is provided. The spindle of the right-side spindle unit 12R is parallel to the Z direction and opposes (faces) the spindle of the left-side spindle unit 12L of the left-side machining unit 11L in the left-right direction. Therefore, the left-side and right-side machining units 11L, 11R are arranged symmetrically, forming a so-called opposed two-spindle lathe. The left-side and right-side machining units 11L, 11R do not have to be symmetrical. Furthermore, the right-side machining unit 11R does not have to have the same configuration as the left-side machining unit 11L. For example, at least one of the left-side processing device 11L and the right-side processing device 11R may be another type of processing device such as a machining center.

The machine tool 1 is also a multi-tasking machine equipped with the functions of both an NC lathe and a machining center. Figure 4 is a right side view of the machine tool 1 in the state shown in Figure 3. As shown in Figures 2 to 4, a tool spindle unit 21 is provided approximately in the center of the machine tool 1 in the left-right direction. The tool spindle unit 21 performs machining that is difficult to perform with the left and right machining units 11L, 11R, which are lathes. The tool spindle unit 21 can perform machining such as drilling in addition to lathe machining on workpieces held by the left and right spindle units 12L, 12R, respectively, and enables workpiece machining at depths and angles that are difficult to perform with the left and right turrets 13L, 13R.

The machine tool 1 comprises a multi-task machine equipped with left and right machining units 11L, 11R and a tool spindle unit 21 mounted on a single bed 22. The left and right spindle units 12L, 12R each rotate a workpiece W (see FIG. 4) driven by spindle motors 14L, 14R mounted outside the unit. The left and right spindle units 12L, 12R, including the spindle motors 14L, 14R, are slidable in a direction parallel to the Z direction along an inclined surface 23 on the slant-bed structure of the bed 22. The left and right spindle units 12L, 12R move in a direction parallel to the Z direction, for example, by driving a ball screw mechanism (not shown) via a Z-axis servo motor 17 (see FIG. 4) mounted below. The left and right turrets 13L, 13R and the tool spindle unit 21 are all movable in the longitudinal and vertical directions of the machine body, which are perpendicular to the spindles. For example, the movement direction of the tool spindle device 21 is the horizontal Y direction and the vertical X direction, while the movement directions of the left and right turrets 13L, 13R are the YL direction and the XL direction, which are inclined 45 degrees from the Y direction and the X direction.

An automatic tool changer 25 is also provided in front of the tool spindle unit 21. The tool spindle unit 21 can exchange tools T (spindle head tools) with the automatic tool changer 25. The automatic tool changer 25 has a tool magazine 25A containing multiple tools T at its top, and a tool changer 25B, located opposite the tool spindle unit 21, transports a replacement tool T from the tool magazine 25A to the tool exchange position of the tool spindle unit 21. The machine tool 1 can also exchange tools on the tool spindle unit 21 while machining a workpiece W with each of the left and right machining devices 11L, 11R. The machine tool 1 is equipped with, for example, separation shutters (not shown) located on both the left and right sides of the tool spindle unit 21 in the Z direction. The machine tool 1 can move the two separation shutters individually in the Y direction using a drive mechanism (not shown). Figure 3 shows the separation shutters in a retracted position. In the machine tool 1, two separation shutters separate the machining spaces of the left-side machining unit 11L and the right-side machining unit 11R from the tool changing space of the tool spindle unit 21. This prevents each unit from being affected by coolant or chips. Furthermore, by closing only one of the separation shutters, the space including the tool changing space can be expanded to the machining space of one of the turrets or the tool spindle unit 21.

The work transport device 14 transfers the workpiece W between the left and right processing devices 11L, 11R and each device for carrying in, unloading, inspecting, etc. the workpiece. The left and right processing devices 11L, 11R and each device for transferring the workpiece W are examples of counterpart devices of the present disclosure. The machine tool 1 is equipped with a stocker device 9 as one of the counterpart devices. As shown in FIG. 1, the stocker device 9 has multiple pallets 10 on which the workpieces W can be stacked, and swaps the pallets 10 at the work position based on the control of the control device 15. The work transport device 14 receives the workpiece W before machining and transfers the workpiece W after machining between the pallets 10 at the work position. Details of the work transport device 14 will be described later.

As shown in Figures 1 and 2, the operation panel 3 is provided on the front of the device cover 2 and includes a touch panel 3A and an operating device 3B. The operating device 3B includes, for example, operating switches, push buttons, dials, indicator lamps, etc. The operation panel 3 accepts operation inputs from the user via the touch panel 3A and the operating device 3B, and outputs signals corresponding to the accepted operation inputs to the control device 15. The operation panel 3 also changes the display content of the touch panel 3A and the lighting status of the indicator lamps on the operating device 3B based on the control of the control device 15. A pendant 8 for operating the machine tool 1 can be suspended below the center of the device cover 2.

As shown in FIG. 2, the control device 15 of the machine tool 1 is a computer-based processing device equipped with a CPU 15A and a storage device 15B. The storage device 15B includes, for example, RAM, ROM, flash memory, etc. The control device 15 is electrically connected to each device (such as the left-side machining device 11L and the workpiece transport device 14) and is capable of controlling each device. Various control programs 16 are stored in the storage device 15B. The control programs 16 include, for example, NC programs that control the operation of the left-side and right-side machining devices 11L and 11R when machining a workpiece, programs that control the operation of the workpiece transport device 14, and ladder circuit programs that process various signals. The control program 16 also stores, in association with each other, the X, Y, and Z coordinates of the transfer position where the workpiece transport device 14 transfers the workpiece W, the name of the process to be performed at that transfer position, and identification information for identifying that process. In the following description, the coordinates in the X, Y, and Z directions will be referred to as the X, Y, and Z coordinates. This coordinate system is used for convenience of explanation and can be changed as appropriate. The setting of each coordinate is not limited to the above setting, and for example, the left-right direction (Z direction) may be set as the X coordinate, the front-back direction as the Y coordinate, and the up-down direction (X direction) as the Z coordinate.

(Regarding the workpiece transport device 14)
Next, the workpiece transport device 14 will be described in detail. As shown in Figures 1, 3, and 4, the workpiece transport device 14 is, for example, a gantry-type transport device, and is capable of moving the gripped workpiece W in three directions, the X, Y, and Z directions. Note that Figure 1 illustrates the workpiece transport device 14 moving to multiple positions in a single drawing.

The machine tool 1 includes a tower-shaped frame structure 31 with beams connected to front, rear, left, and right columns erected to match the width of the bed 22. The front sides of the various devices on the bed 22, such as the tool spindle device 21, the automatic tool changer 25, and the workpiece transport device 14, are covered by an equipment cover 2 supported by the frame structure 31. As shown in Figures 3 and 4, the workpiece transport device 14 includes a rail base 32 and a traveling table 33. The rail base 32 is located on the front side of the device, above the frame structure 31. Two traveling rails 34 parallel to the Z direction and one traveling rack 35 are provided on the rail base 32. The traveling table 33 is slidable along the traveling rails 34. A traveling motor 37 is fixed to the traveling table 33. The traveling table 33 is movable in the Z direction when a pinion fixed to the rotation shaft of the traveling motor 37 engages with the traveling rack 35. The control device 15 controls the travel motor 37 to move the workpiece transport device 14 to any position in the Z direction.

A slide base 39 is provided on the upper surface of the traveling table 33 so that it can slide in the Y direction. A rack is provided on the side of the slide base 39 for moving it in the Y direction. A forward/backward motor 41 is fixed to the traveling table 33. A pinion fixed to the rotation shaft of the forward/backward motor 41 is engaged with the rack of the slide base 39. The control device 15 can move the slide base 39 to any position in the Y-axis direction (forward/backward direction) by controlling the forward/backward motor 41. The slide base 39 protrudes forward from the frame structure 31, and a lifting arm 43 that moves up and down is provided at its tip.

A support column 45 equipped with a lifting rail is fixed to the front end of the slide table 39 in a position parallel to the X direction. A lifting arm 43 is provided in front of the support column 45. The lifting arm 43 is movable in the X direction along the lifting rail of the support column 45. A lifting motor 47 is provided at the top of the support column 45. A pulley is fixed to the rotation shaft of the lifting motor 47. A belt is stretched between the pulley of the lifting motor 47 and a pulley journaled at the bottom of the support column 45. The lifting arm 43 is connected to the belt, and its position in the X direction is changed in response to the drive of the lifting motor 47. The control device 15 can change the position of the lifting arm 43 in the X-axis direction (up and down direction) by controlling the lifting motor 47. A head 51 for gripping the workpiece W is provided at the lower end 43A of the lifting arm 43. Therefore, the control device 15 can move the head 51 to any position in the X, Y and Z directions by controlling the travel motor 37, the front-rear motor 41 and the lift motor 47.

The head 51 is attached to the rear surface of the lower end 43A and is positioned rearward relative to the lifting arm 43. Figure 5 shows an oblique view of the lifting arm 43 and head 51. The head 51 has two gripping portions: a first gripping portion 52 and a second gripping portion 53. The second gripping portion 53 has the same configuration as the first gripping portion 52. Therefore, in the following explanation, the explanation of the second gripping portion 53 will be omitted as appropriate.

As shown in FIG. 5, the head 51 includes a support member 56, a first claw member 57, and a second claw member 58. The support member 56 is attached to the rear of the lower end 43A of the lifting arm 43. The support member 56 is a generally rectangular plate with a predetermined thickness. A first gripping portion 52 and a second gripping portion 53 are provided on each side of the support member 56 that face each other in the thickness direction (from the front left to the rear right in FIG. 5). The support member 56 is rotatably attached to the lower end 43A. The control device 15 rotates the head 51 around a rotation axis 62 (see FIGS. 4 and 5) parallel to the Y direction, for example, by driving a rotation motor (not shown) provided in the lower end 43A. As a result, the support member 56 rotates in the rotation direction 61 (see FIGS. 4 and 5), orienting the first and second gripping portions 52, 53 in different directions.

The head 51 rotates in a rotation direction 61 (clockwise or counterclockwise) by 90 degrees increments, for example, in response to the drive of the rotation motor. The head 51 rotates to a total of four rotation positions: one rotation position (two rotation positions, including a 180-degree inverted position) in which the first and second grippers 52, 53 are each oriented to both sides in the Z direction (left and right sides), and one rotation position (two rotation positions, including a 180-degree inverted position) in which the first and second grippers 52, 53 are each oriented to both sides in the X direction (top and bottom sides). In the following description, the rotation positions in which the first gripper 52 is oriented left, up, right, and down, respectively, are referred to as first to fourth rotation positions RP1 to RP4. For example, when transferring a workpiece W between the first gripper 52 and the left spindle unit 12L as shown in FIG. 6 (described later), the control device 15 sets the head 51 to the first rotation position RP1. Furthermore, for example, as shown in FIG. 8 (described later), when transferring a workpiece W between the first gripper 52 and the stocker device 9, the control device 15 rotates the head 51 to a fourth rotation position RP4 where the first gripper 52 faces downward. Note that the rotation angle and rotation position of the head 51 described above are merely examples. For example, the head 51 may be configured to rotate at intervals of an angle greater than 90 degrees (such as 180 degrees) or at intervals of a smaller angle (such as 45 degrees), or may be configured to rotate at any rotation angle.

The first gripping unit 52 can be fitted with, for example, three first claw members 57. Each of the three first claw members 57 has, for example, the same shape and is fitted at positions offset 120 degrees in the circumferential direction. The three first claw members 57 are detachably attached to the support member 56 and can be replaced with different types of first claw members 57 depending on the type of workpiece W, etc. The three first claw members 57 also slide radially (open and close) in response to the actuation of a hydraulic cylinder (not shown) provided in the head 51. As a result, the control device 15 closes the three first claw members 57 to clamp the workpiece W, or opens the three first claw members 57 to release the clamping, by actuating the hydraulic cylinder. Similarly, the second gripping unit 53 can be fitted with, for example, three second claw members 58, which can be opened and closed.

(Regarding the reference position setting process)
Next, the process of setting the reference position of the head 51 will be described. The control device 15 performs machining on the workpiece W based on the control program 16. The workpiece W to be machined is transported, for example, by the workpiece transport device 14 from the stocker device 9 to the left spindle device 12L or the right spindle device 12R. After transferring the workpiece W to each spindle device, the control device 15 performs predetermined machining using the left and right turrets 13L, 13R and the tool spindle device 21. The control device 15 receives the machined workpiece W from the left spindle device 12L, etc., to the workpiece transport device 14, and transports it to the stocker device 9.

For example, the NC program of the control program 16 sets the XYZ coordinates of the transfer position, which is the position of the head 51 where the workpiece W is transferred between the workpiece transport device 14 and each of the other devices. The control device 15 positions the head 51 at the transfer position (XYZ coordinates) set in the NC program and rotates the head 51 to a predetermined rotation position to transfer the workpiece W between the head 51 and the other device. The machine tool 1 of this embodiment is capable of setting a reference position, which serves as a reference for setting the transfer position, using a contact detection device. The control device 15 uses the length of the workpiece W input by the user as an input value and corrects each transfer position based on the preset reference position and the input length value. In the following explanation, as an example, the left spindle unit 12L is used as the other device, and a case where the workpiece W is transferred from the first gripper 52 of the head 51 to the left spindle unit 12L is described. Note that, as will be described later with reference to FIG. 8, similar settings can be implemented for other transfer positions.

In Figure 6, the upper diagram shows the state of the left spindle unit 12L and head 51 when the reference position is set, and the lower diagram shows the state of the left spindle unit 12L and head 51 when the workpiece is transferred. As shown in the upper diagram of Figure 6, when the reference position is set, a master workpiece 63 is attached to the left spindle unit 12L. This master workpiece 63 is used as a member that comes into contact with the contact detection device 65 when setting the reference position P1, and is also used as a member for checking spindle misalignment during spindle centering operations. The master workpiece 63 has, for example, a disk-shaped clamped portion 63A and a roughly cylindrical convex portion 63B that protrudes from the center of the clamped portion 63A. Note that the shape of the master workpiece 63 shown in Figure 6 is just one example.

The left-side spindle unit 12L can be fitted with multiple (e.g., three) child jaws 67 that can clamp, for example, the workpiece W or the master workpiece 63. Each of the multiple child jaws 67 has the same shape and is fitted at positions offset circumferentially by a predetermined rotational angle (e.g., 120 degrees). Furthermore, the multiple child jaws 67 move radially based on the drive of a drive source (e.g., hydraulic cylinder) provided in the left-side spindle unit 12L, clamping the workpiece W or the master workpiece 63. The member that holds the workpiece W or the master workpiece 63 is not limited to a jaw member such as the child jaws 67, but may be another member such as a collet chuck.

When setting the reference position P1 using the contact detection device 65, the master workpiece 63 is clamped by multiple child jaws 67. For example, the user operates the operation panel 3 to open the child jaws 67 and seat the master workpiece 63 on the left spindle unit 12L. The user then operates the operation panel 3 to close the child jaws 67, causing the child jaws 67 to clamp the clamped portion 63A of the master workpiece 63. The master workpiece 63 contacts the abutment portion 67A formed on the child jaws 67, and is positioned in a state where movement toward the base end of the left spindle unit 12L (left side in Figure 6) is restricted. Furthermore, the centers of the clamped portion 63A and the convex portion 63B of the master workpiece 63 are aligned with the spindle 69. In other words, when the master workpiece 63 is positioned correctly for measurement, movement toward the base end is restricted, and the center of rotation is aligned with the spindle 69. The operation of placing the master workpiece 63 on the left spindle device 12L may be performed automatically by the head 51 of the workpiece transport device 14. For example, in response to an instruction to start measurement, the control device 15 may cause the head 51 to grip the master workpiece 63 placed on the stocker device 9, transport the master workpiece 63 to the left spindle device 12L, and hand over the master workpiece 63 from the head 51 to the left spindle device 12L.

When the user places the master workpiece 63 on the left spindle unit 12L, the user clamps the contact detection device 65 in the first gripping portion 52 of the head 51. The user can clamp the contact detection device 65 in the head 51 by operating the operation panel 3, as with the master workpiece 63, or the contact detection device 65 can be placed in a stocker unit 9 or workstation and automatically grasped by the head 51. In the example shown in Figure 6, different shapes of first claw members 57 are used when setting the reference position (top figure) and when transferring the workpiece (bottom figure). It is preferable to change the first claw member 57 to one suitable for clamping the contact detection device 65 and clamping the workpiece W, but the same type of first claw member 57 may be used when setting the reference position and when transferring the workpiece.

The contact detection device 65 is, for example, a touch probe. When the tip of the stylus 65A comes into contact with another component, it transmits a contact detection signal indicating the occurrence of contact via wireless communication. As shown in FIG. 2, the control device 15 includes a wireless device 18 capable of wireless communication with the contact detection device 65. The control device 15 can receive the contact detection signal SI via wireless communication from the contact detection device 65 held by the first claw member 57 of the head 51. The contact detection method used by the contact detection device 65 (touch probe) is not particularly limited, and may include a movable contact method, a pressure sensor method, an optical sensor method, and the like. Therefore, the contact detection device disclosed herein is not limited to a touch probe, and may also include a push button switch with a movable contact or a pressure sensor. Furthermore, the method of transmitting the contact detection signal SI to the control device 15 is not limited to wireless communication, and may include infrared or electromagnetic induction methods. The contact detection signal SI may also be transmitted via wired communication.

After clamping the contact detection device 65 to the head 51, the user operates the operation panel 3 to issue an instruction to begin measuring the reference position P1. Upon receiving the instruction to begin measurement, the control device 15 positions the head 51 at a predetermined measurement start position P2 (see Figure 6). This measurement start position P2 is the position at which the head 51 is positioned when measurement of the reference position P1 begins. For example, if a centering operation or the like is performed in advance and the head 51 is positioned at the measurement start position P2 in Figure 6, the X coordinate in the X direction and the Y coordinate in the Y direction of the head 51 at the measurement start position P2 will match the X and Y coordinates of the spindle 69 of the left spindle unit 12L. For example, based on the user's operation instruction, the control device 15 contacts the stylus 65A of the contact detection device 65 with multiple points on the convex portion 63B of the master workpiece 63, detects the center position of the convex portion 63B, corrects the misalignment with the spindle 69, and performs centering. After placing the head 51 at the measurement start position P2, the control device 15 moves the head 51 in the Z direction and sets the Z coordinate in the Z direction based on the detection of the contact detection device 65. The control device 15 can use the X and Y coordinates of the spindle 69 for the X and Y coordinates. Therefore, the control device 15 sets the X and Y coordinates of the spindle 69 determined by performing the centering operation (the X and Y coordinates of the measurement start position P2) as the X and Y coordinates of the reference position P1.

Once the control device 15 positions the head 51 at the measurement start position P2, it keeps the X and Y coordinates constant and moves the head 51 toward the left spindle unit 12L in a direction parallel to the Z direction (see the arrow indicating the measurement start position P2 in Figure 6). The control device 15 controls the travel motor 37 to move the head 51 in a direction parallel to the Z direction. When the stylus 65A contacts the head 51-facing surface of the convex portion 63B, the contact detection device 65 transmits a contact detection signal SI. When the control device 15 receives the contact detection signal SI from the contact detection device 65, it sets the Z coordinate of the reference position P1. For example, the control device 15 compensates for the delay time required for the contact detection signal SI to be transmitted from the contact detection device 65 to the control device 15 relative to the time at which the contact detection signal SI was received, and calculates the output time at which the contact detection signal SI was output. The control device 15 then sets the Z coordinate at which the head 51 was positioned at the output time as the Z coordinate of the reference position P1. The Z coordinate of the head 51 can be detected based on the position information of the drive motor 37. The control device 15 does not need to perform the delay correction of the transmission time. For example, the control device 15 may set the Z coordinate of the head 51 at the time when the contact detection signal SI is input as the Z coordinate of the reference position P1.

The control device 15 sets the reference distance L1, for example, to the distance in the Z direction from the origin position P3 to the reference position P1 shown in FIG. 6. This origin position P3 is the reference (origin) position for determining the transfer position. The origin position P3 may be set to a position other than the left spindle unit 12L (such as a predetermined position on the frame structure 31). In other words, the origin position P3 is not limited to the position of the left spindle unit 12L and can be set to any position on the machine tool 1. Once the control device 15 has completed setting the reference distance L1, it displays on the operation panel 3 that the reference position setting process has been completed. Once the user confirms the completion display, they can remove the contact detection device 65 from the head 51, remove the master workpiece 63 from the left spindle unit 12L, and replace the first jaw member 57 with one appropriate for the workpiece W to be machined.

(Position setting process, processing operation)
Next, the position setting process and machining operation of the machine tool 1 will be described. Before machining the workpiece W, the control device 15 receives the length of the workpiece W to be machined. The control device 15 may perform the process of receiving this length as an input value before receiving an instruction to start machining. For example, the control device 15 displays on the touch panel 3A a reception screen for inputting the length of the workpiece W in response to a predetermined operation input on the touch panel 3A. Figure 7 shows an example of a reception screen 73 for inputting the length of the workpiece W. As shown in Figure 7, the control device 15 receives, as input values, information such as the position name, the weight of the workpiece W, the length of the workpiece W, the rotation position, and whether or not to transfer the workpiece W. Note that the input values shown in Figure 7 are merely examples.

For example, consider a case in which the machining process sequentially involves machining a workpiece W held by the left spindle unit 12L (first machining process) and machining a workpiece W held by the right spindle unit 12R (second machining process). In this case, the workpiece W is transferred six times. The control device 15 identifies the transfer positions by setting position names NO1 to NO6 as the names of the transfer positions for these six transfers. Specifically, the head 51 receives the workpiece W from the stocker unit 9 to the first gripper 52 at position NO1, and transfers the workpiece W from the first gripper 52 to the left spindle unit 12L at NO2. The head 51 also receives the workpiece W after the first machining process from the left spindle unit 12L to the first gripper 52 at NO3, and transfers the workpiece W from the first gripper 52 to the right spindle unit 12R at NO4. Then, the head 51 receives the workpiece W after the second machining process from the right spindle device 12R at NO5, and delivers the workpiece W to the stocker device 9 at NO6.

At the top of the reception screen 73 in Figure 7, input value names 75 are displayed to explain each input value. Below each input value name 75, an input field 76 is provided for entering each input value for each position name (transfer position). In the example shown in Figure 7, transfer positions NO1 to NO6 are set in order from top to bottom. The top position name NO1 is the transfer position where the unmachined workpiece W is transferred from the stocker device 9 to the first gripper 52. Therefore, the user inputs the weight of the unmachined workpiece W as the input value weight X1, and the length of the unmachined workpiece W as length Y1 in the input field 76. For example, when entering the weight X2 and length Y2 after the first processing step of NO3, the user inputs the weight X2 that has been reduced and the length Y2 that has been shortened by the first processing step. The user also inputs, for example, information on the rotation position of the head 51 for each position (first to fourth rotation positions RP1 to RP4) and information on whether the workpiece W is to be transferred from the head 51 to the receiving screen 73. When the setting button 77 on the receiving screen 73 is touched, the control device 15 stores the input value on the receiving screen 73 in the storage device 15B and uses it to correct the transfer position, as described below. In this way, the control device 15 accepts the length of the workpiece W as an input value for each transfer position. When the cancel button 78 on the receiving screen 73 is touched, the control device 15 discards the information accepted on the receiving screen 73. Note that the method for acquiring the weight input value is not limited to the method of inputting the weight via the operation panel 3 described above. For example, a setting file containing the input value may be loaded into the control device 15. Alternatively, the control device 15 may not accept the length input value on the receiving screen 73 in advance, but may accept the length input value after accepting a machining start instruction and before starting machining. Furthermore, the screen configuration of the reception screen 73 in FIG. 7 is an example, and the reception screen 73 does not necessarily need to include information such as weight, rotation position, and whether or not there is a transfer.

The following explanation focuses on position No. 2 (see FIG. 7), shown in the lower diagram of FIG. 6, where the workpiece W is transferred from the first gripper 52 of the head 51 to the left spindle unit 12L. In this case, the control device 15 accepts the length L2 of the unmachined workpiece W (see FIG. 6) as the length Y1 of the workpiece W for position No. 2. The user may enter, for example, a value on the drawing (design) of the unmachined workpiece W as length L2, or an actual measurement of the workpiece W before machining. The control device 15 sets the transfer position for position No. 2 using the accepted length L2 of the workpiece W. For example, as shown in the lower diagram of FIG. 6, the control device 15 calculates design position P5, which is the design position of the head 51 during transfer, based on the accepted length L2 of the workpiece W. Design position P5 is a calculated position that takes into account, for example, the design lengths of each component, and does not include errors in the Z direction due to component assembly errors. As shown in the diagram below, the workpiece W transferred from the first gripping unit 52 is seated against the abutment portions 67A of the child jaws 67 and is clamped by the multiple child jaws 67. The X and Y coordinates of the design position P5 are the same as those of the reference position P1, for example, because they have been adjusted by a centering operation. Meanwhile, the distance L3 in the Z direction from the origin position P3 to the design position P5 is, for example, the sum of the distance L4 from the origin position P3 to the abutment portions 67A of the child jaws 67, the length L2 of the workpiece W, and the distance L5 from the workpiece W to the design position P5 (L3 = L4 + L2 + L5).

Distance L4 corresponds to the distance from the origin position P3 to the workpiece W held by the sub-jaw 67 of the left spindle unit 12L and can be preset depending on the structure of the sub-jaw 67. Distance L5 is, for example, the distance from the end of the workpiece W held by the first jaw member 57 on the support member 56 side to the center of the head 51 and can be preset depending on the structure of the head 51. After calculating distance L3, the control device 15 calculates a correction distance L6, which is the difference between distance L3 and the reference distance L1 calculated when the reference position was set. Here, assembly errors specific to the device may occur in the workpiece transport device 14, the left spindle unit 12L, etc. As a result, the designed transfer position may differ from the actual transfer position, including the actual assembly error, making it difficult to accurately execute the transfer operation. Specifically, this may result in chucking errors of the workpiece W or interference between the workpiece W and the sub-jaw 67.

When setting the reference distance L1 described above, the contact detection device 65 is used to set the reference distance L1, which is a distance that includes errors in the assembly accuracy of the components of the left spindle unit 12L and the workpiece transport device 14, i.e., the actual measured distance. The control device 15 then sets the transfer position of the head 51 based on this reference distance L1, thereby correcting the error. Specifically, as shown in FIG. 6, the control device 15 corrects the Z coordinate by adding the correction distance L6 to the reference distance L1 in the Z direction and setting it as the Z coordinate of the transfer position P6 of position name No. 2. In the example shown in FIG. 6, the transfer position P6 is located to the right of the reference position P1, but the positional relationship can be changed depending on the contact detection device 65 and the length of the workpiece W.

The control device 15 then sets this transfer position P6 in the NC program, setting it as the transfer position for position name No. 2 where the workpiece W is transferred from the first gripper 52 to the left spindle device 12L. This allows the transfer position P6 to be set while correcting for component assembly errors, etc., enabling the transfer of the workpiece W to be carried out with high precision. The control device 15 then transfers the workpiece W from the head 51 to the left spindle device 12L using the set transfer position P6. Specifically, when the control device 15 positions the head 51 gripping the workpiece W at the transfer position P6, it causes the child jaws 67 to clamp the workpiece W. The control device 15 releases the chuck of the first jaw member 57, retracts the head 51, and then rotates the left spindle device 12L to begin processing.

As described above, in the reference position setting process, the control device 15 of this embodiment sets the reference position P1 based on the origin position P3 of the left spindle unit 12L. This allows the reference position P1 to be set accurately using the measurement results of the contact detection device 65, with a predetermined position of the mating device, the left spindle unit 12L, as the origin and the origin as the reference. Furthermore, in the position setting process, the control device 15 calculates the design position P5 of the head 51 based on the input length of the workpiece W and the origin position P3 of the left spindle unit 12L. The control device 15 corrects the transfer position P6 based on the difference between the design position P5 and the reference position P1 (correction distance L6). This allows the correction distance L6 to be calculated accurately using the reference distance L1, which is the actual measurement value, and the design distance L3. The method of calculating the correction distance L6 is not limited to using the origin position P3 described above; for example, the initial position of the workpiece transport device 14 may also be used as the reference.

In addition, during the reference position setting process, the control device 15 uses the contact detection device 65, which is a touch probe, to bring the stylus 65A into contact with the left spindle unit 12L (master workpiece 63) and acquire a contact detection signal SI via wireless communication. The control device 15 sets the reference position P1 based on the position of the head 51 at the time the contact detection signal SI is output. This eliminates the need for a cable connecting the contact detection device 65 to the control device 15 when measurements are performed with the contact detection device 65 held by the head 51. Furthermore, by providing a wireless device 18 to each of multiple machine tools 1, the contact detection signal SI can be acquired from the contact detection device 65 at each machine tool 1, allowing the contact detection device 65 to be shared among multiple machine tools 1. This eliminates the need to provide a contact detection device 65 on every machine tool 1, thereby reducing the manufacturing cost of the machine tool 1.

In addition, in the position setting process, the control device 15 acquires as an input value the length L2 of the workpiece W along the spindle 69 of the workpiece W while it is held by the left spindle device 12L. The control device 15 sets the transfer position P6 in the Z direction parallel to the spindle 69 based on the acquired input value and the reference position P1. This allows the input value to correct any error in the transfer position P6 in the direction along the spindle 69 of the left spindle device 12L.

In the above example, the transfer position for position No. 2 was described, but similar corrections can be made for other transfer positions. For example, in the machining processes for position Nos. 1 to 6 described above, two machining operations are performed, so the length of the workpiece W can change to three different lengths: the unmachined length Y1, the length after the first machining operation Y2, and the length after the second machining operation Y3. Therefore, the control device 15 accepts the three lengths Y1, Y2, and Y3, as shown on the reception screen 73 in Figure 7.

For example, based on user operation, the control device 15 uses the contact detection device 65 to set the reference position P1 and reference distance L1 required for other position names Nos. 1, 3, and 6, similar to the above-mentioned position name No. 2. Furthermore, as shown in FIG. 7, the control device 15 accepts three lengths Y1, Y2, and Y3 as input values. For the three lengths Y1, Y2, and Y3, the control device 15 may accept the length values themselves as input values, or the difference in length. For example, the control device 15 may accept the unprocessed length Y1 and the difference in length resulting from each processing step. For example, the control device 15 performs correction using the unprocessed length Y1 for position names Nos. 1 and 2, the length after the first processing step Y2 for position names Nos. 3 and 4, and the length after the second processing step Y3 for position names Nos. 5 and 6.

Therefore, in the position setting process, the control device 15 acquires, for example, the length Y1 of the workpiece W before machining as a first input value, the length Y2 of the workpiece W after machining by the left-side machining device 11L as a second input value, and the length Y3 of the workpiece W after machining by the right-side machining device 11R as a third input value. The control device 15 sets the transfer position P6 when transferring the workpiece W to the left-side machining device 11L based on the length Y1. The control device 15 also sets the transfer position when transferring the workpiece W to the right-side machining device 11R based on the length Y2. The control device 15 also sets the transfer position when transferring the workpiece W to the stocker device 9 based on the length Y3. As a result, similar to the transfer from the first gripper 52 to the left-side spindle device 12L described above, each transfer position can be set to compensate for component assembly errors, allowing for accurate transfer.

Figure 8 shows an example of transferring a workpiece W between the head 51 and the stocker device 9. The pallet 10 in Figure 8 is located at the work position of the stocker device 9. The pallet 10 of the stocker device 9 is provided with, for example, multiple positioning pins 10A. The workpiece W placed on the top surface of the pallet 10 is placed with its axial direction aligned in the vertical direction by the multiple positioning pins 10A. The head 51 transfers the workpiece W to and from the pallet 10, for example, at the fourth rotation position RP4 with the first gripper 52 facing downward. In this case, the control device 15 corrects the X coordinate in the X direction. As shown in the upper diagram of Figure 8, the control device 15 sets a reference position P1 in the X direction based on the position of the head 51 when the contact detection device 65 held by the head 51 is brought into contact with, for example, the top surface of the pallet 10. For example, the control device 15 receives the length of the unprocessed workpiece W (length Y1 of position name No. 1 on the reception screen 73) as the length of the workpiece W when it is received by the head 51 from the pallet 10. The control device 15 also receives the length after the second processing (length Y3 of position name No. 6 on the reception screen 73) as the length when the workpiece W is transferred to the pallet 10. The control device 15 then calculates the distance L3 and the correction distance L6 in the X direction based on the received lengths Y1 and Y3, and corrects the X coordinate of the transfer position P6 of position names No. 1 and No. 6.

The control device 15 can therefore set the transfer position P6 for various cases, such as the transfer of an unmachined workpiece W, the transfer of a machined workpiece W, the transfer of a workpiece W from the head 51 to a partner device, and the receipt of a workpiece W from a partner device to the head 51. By accepting the lengths Y1 to Y3 of three types of workpiece W as input values, the control device 15 can accurately correct the transfer position P6 using the correction distance L6 based on each length Y1 to Y3 and the reference position P1, as in the case of Figure 6 above. The user can change the transfer position for each position by changing each length Y1 to Y3.

Furthermore, with the above-described configuration, the same reference position P1 and reference distance L1 can be used for different types of workpieces W. Even if the type of workpiece W is different, the distance between the left spindle unit 12L and the head 51 merely varies depending on the length of the workpiece W; essentially, the same reference position P1 can be used. For example, the user inputs the length of the next workpiece W to be machined on the reception screen 73 each time a changeover is performed to change the workpiece W to be machined. The control device 15 uses the same reference position P1 when setting the transfer position P6 for transferring a given workpiece W from the head 51 to the other device and when setting the transfer position P6 for a workpiece W of a different type from the given workpiece W. With this configuration, even when a changeover is performed, it is not necessary to perform the reference position setting process using the contact detection device 65 again. This reduces the work time associated with the changeover and improves production efficiency. It is also possible to perform the reference position setting process using the contact detection device 65 each time a changeover is performed.

Incidentally, the stocker device 9 is an example of a counterpart device or a stand. The left-side spindle device 12L is an example of a counterpart device or a first spindle device. The right-side spindle device 12R is an example of a counterpart device or a second spindle device. The left-side turret 13L is an example of a first processing device. The right-side turret 13R is an example of a second processing device. The work transport device 14 is an example of a robot. The tool spindle device 21 is an example of a first and second processing device. The first claw member 57 and the second claw member 58 are examples of holding members. The lengths Y1, Y2, and Y3 are examples of a first input value, a second input value, and a third input value.

As described above, the present embodiment provides the following effects.
In one aspect of the present embodiment, the control device 15 brings the contact detection device 65 held by the head 51 into contact with the left spindle device 12L, and sets a reference position P1 of the head 51 at the time of contact based on the contact detection signal SI obtained from the contact detection device 65. This makes it possible to set the reference position P1 taking into account errors in the assembly accuracy of parts such as the head 51. The control device 15 then obtains the length L2 of the workpiece W as an input value, and sets a transfer position P6 for transferring the workpiece W from the head 51 to the left spindle device 12L based on the input value and the reference position P1. This eliminates the need to provide a sensor or the like on the mating device, and allows the transfer position P6 to be set with high accuracy based on the measurement results while simplifying the entire machine tool 1.

It goes without saying that the present disclosure is not limited to the above-described embodiments, and various improvements and modifications are possible within the scope of the present disclosure.
For example, in the above embodiment, the machine tool 1 may be configured to include (permanently install) the contact detection device 65. For example, the contact detection device 65 may be permanently installed on a table for placing the workpiece W or on a station for placing tools. In this case, the control device 15 may retrieve the contact detection device 65 using the workpiece transport device 14 when measurement or the like is required, and perform the measurement.
Alternatively, as shown by the dashed line in Fig. 5, contact detection device 165 may be attached to head 51. Contact detection device 165 may be configured, for example, to enable stylus 65A to be extended and retracted, and may be configured to cause stylus 65A to protrude forward beyond first claw member 57 during measurement under the control of control device 15. Furthermore, contact detection device 165 may be configured to store stylus 65A within support member 56 when measurement is not being performed and is not required. In this way, machine tool 1 may be provided with contact detection device 165 as part of its device.
Furthermore, the configuration of the head 51 in the above embodiment is merely an example. For example, although the second gripping portion 53 has the same structure as the first gripping portion 52, it may have a different structure. The number of second claw members 58 may be greater than the number of first claw members 57. Furthermore, although the first and second gripping portions 52, 53 are provided at positions rotated 180 degrees, this is not limiting. For example, the second gripping portion 53 may be provided at a position rotated 90 degrees from the first gripping portion 52. Furthermore, the head 51 may include only the first gripping portion 52 and not the second gripping portion 53.

Furthermore, the master workpiece 63 does not have to be used when setting the reference position shown in FIG. 6 . For example, the reference position P1 may be set by bringing the contact detection device 65 into contact with the center of the face of the left spindle unit 12L facing the head 51 (the center surrounded by multiple child jaws 67, a position on the spindle 69). Therefore, in the above embodiment, the master workpiece 63 is used as the component of the mating device with which the contact detection device 65 comes into contact, but this is not limited thereto. For example, if the left spindle unit 12L has a stopper that seats the workpiece W and grips the workpiece W between it and the child jaws 67, the component with which the contact detection device 65 comes into contact may be the stopper. Furthermore, if the left spindle unit 12L has a master jaw that is arranged opposite the child jaws 67 and grips the workpiece W between it and the child jaws 67, the component with which the contact detection device 65 comes into contact may be the master jaw. Furthermore, if the chuck of the left spindle unit 12L is a collet chuck, the component with which the contact detection device 65 comes into contact may be the collet chuck.
Furthermore, the mating devices are not limited to the left and right spindle devices 12L, 12R and the stocker device 9, but may also be, for example, a workpiece inversion device that inverts the orientation of the workpiece W, a temporary table on which the machined workpiece W is placed so that the user can check it, or a discharge chute that discharges defectively machined workpieces W. Furthermore, although the machine tool 1 is provided with a plurality of mating devices (the left and right spindle devices 12L, 12R, and the stocker device 9) as the mating devices of the present disclosure, it may also be configured to have only one mating device (for example, only one spindle device).
The control device 15 may execute the reference position setting process for each different type of workpiece W.
The robot in the present disclosure is not limited to the gantry-type loader described above, but may also be an articulated robot.
The left and right machining devices 11L, 11R are not limited to lathes with two opposing axes, but may be lathes with two parallel axes. Various configurations can be used for the left and right machining devices 11L, 11R, such as a horizontal lathe, a face lathe, a vertical lathe, a machining center, a milling machine, or a drill press.

1 Machine tool, 9 Stocker device (counter device, stand), 12L Left side spindle device (counter device, first spindle device), 12R Right side spindle device (counter device, second spindle device), 13L Left side turret (first processing device), 13R Right side turret (second processing device), 14 Workpiece transport device (robot), 15 Control device, 21 Tool spindle device (first and second processing devices), 57 First jaw member (holding member), 58 Second jaw member (holding member), 63 Master workpiece, 65 Contact detection device, 69 Spindle, L2 Length, P1 Reference position, P3 Origin position, P6 Delivery position, SI Contact detection signal, Y1 Length (first input value), Y2 Length (second input value), Y3 Length (third input value), W Workpiece.

Claims (6)

a contact detection device;
a robot having a holding member, which holds a workpiece with the holding member and transports the workpiece;
a counterpart device that receives the workpiece from the robot;
a control device;
Equipped with
The contact detection device
outputting a contact detection signal corresponding to the contact to the control device;
The control device
a reference position setting process for controlling the robot to bring the contact detection device into contact with the counterpart device, acquiring a contact detection signal from the contact detection device when contact with the counterpart device is detected, and setting the position of the robot at the time of contact as a reference position based on the acquired contact detection signal;
a position setting process for acquiring the length of the workpiece as an input value, and setting a transfer position, which is a position of the robot when transferring the workpiece having the length of the input value from the robot to the partner device, based on the acquired input value and the reference position;
Run
The contact detection device
a touch probe that transmits the contact detection signal to the control device by wireless communication while being held by the holding member of the robot;
the control device
In the reference position setting process, the reference position is set based on the position of the robot at the time when the contact detection device outputs the contact detection signal when the contact detection device is brought into contact with the counterpart device . a robot having a holding member, which holds a workpiece with the holding member and transports the workpiece;
a counterpart device that receives the workpiece from the robot;
a control device;
Equipped with
The robot
The holding member can hold the contact detection device,
The contact detection device
outputting a contact detection signal corresponding to the contact to the control device;
The control device
a reference position setting process in which the robot is moved while the contact detection device is held by the holding member of the robot, the contact detection device is brought into contact with the counterpart device, a contact detection signal is acquired from the contact detection device when contact with the counterpart device is detected, and the position of the robot at the time of contact is set as a reference position based on the acquired contact detection signal;
a position setting process for acquiring the length of the workpiece as an input value, and setting a transfer position, which is a position of the robot when the workpiece having the length of the input value is transferred from the robot to the counterpart device, based on the acquired input value and the reference position ;
The contact detection device
a touch probe that transmits the contact detection signal to the control device by wireless communication while being held by the holding member of the robot;
the control device
In the reference position setting process, the reference position is set based on the position of the robot at the time when the contact detection device outputs the contact detection signal when the contact detection device is brought into contact with the counterpart device . The control device
3. The machine tool according to claim 1, wherein in the reference position setting process, the reference position is set using an origin position of the counterpart device as a reference. The control device: In the position setting process, the input value is acquired for each type of workpiece, and the same reference position is used when setting the transfer position when transferring any of the workpieces from the robot to the other device and when setting the transfer position when transferring a workpiece of a different type from the any of the workpieces from the robot to the other device. a plurality of the counterpart devices;
The plurality of counterpart devices
a first spindle unit and a second spindle unit that hold and rotate the workpiece;
a table on which the workpiece can be placed;
Including,
The machine tool comprises:
a first machining device that performs machining on the workpiece held by the first spindle device;
a second machining device that performs machining on the workpiece held by the second spindle device;
Equipped with
The stand is
The workpiece can be placed on the worktable after the processing by the first processing device and the second processing device is completed,
The control device of claim 1 or claim 2, wherein in the position setting process, the length of the workpiece before machining is acquired as a first input value, the length of the workpiece after machining is completed by the first machining device as a second input value, and the length of the workpiece after machining is completed by the second machining device as a third input value, and the transfer position when transferring the workpiece to the first machining device is set based on the first input value, the transfer position when transferring the workpiece to the second machining device is set based on the second input value, and the transfer position when transferring the workpiece to the table is set based on the third input value. The other device is
a spindle device that holds the workpiece and rotates the workpiece around a spindle,
3. The control device of claim 1, wherein in the position setting process, the length of the workpiece along the spindle while it is held by the spindle device is acquired as the input value, and the transfer position in a direction parallel to the spindle is set based on the acquired input value and the reference position.