Machine tool and control method for machine tool

Abstract

To provide an inexpensive and miniaturized machine tool and a control method for the machine tool. [Solution] The machine tool 1 includes a tool spindle 4 on which a long tool TL of a length greater than a fixed length and a normal tool TS shorter than a predetermined length are interchangeably mounted; a tool storage device 5 capable of storing both the long tool TL and the normal tool TS; a tool changer 6 having a first tool gripping part 642 and a second tool gripping part 643 for exchanging the long tool TL or normal tool TS stored in the tool storage device 5 with the mounted tool T1 mounted on the tool spindle 4; and an exchange operation control unit 72 that determines the operation pattern in the tool change operation using the tool changer 6 based on whether the mounted tool T1 is a long tool TL or a normal tool TS and whether the next mounted tool T2 to be mounted on the tool spindle 4 is a long tool TL or a normal tool TS.

Description

Technical Field

[0001] The present invention relates to a machine tool equipped with a tool changing device and a control method for a machine tool equipped with a tool changing device.

Background Art

[0002] A machine tool equipped with a tool changing device that takes out a tool stored in a tool storage device and exchanges it with a tool mounted on a spindle is known (see, for example, Patent Document 1). The machine tool described in this Patent Document 1 is provided with a tool magazine for storing tools of a general length and a long tool storage device for storing long tools longer than tools of a general length. And, it is proposed to omit a drive mechanism only for attaching and detaching a long tool to and from the spindle by attaching and detaching the long tool to and from the spindle using a tool changing device for attaching and detaching tools of a general length.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the machine tool described in Patent Document 1 is configured to provide a moving table that can move up and down and a slide table that can slide in the axial direction in a long tool storage device, and transfer the long tool to the tool changing device by moving the long tool with these moving table and slide table. Therefore, there is a problem that the machine tool becomes expensive. Further, since a space for arranging the long tool storage device and a space for the moving table and the slide table to move are required, there is also a problem that the machine tool becomes large-sized.

[0005] This invention has been made in view of the above-mentioned problems, and aims to provide an inexpensive and miniaturized machine tool and a control method for the machine tool. [Means for solving the problem]

[0006] The machine tool of the present invention, which solves the above problems, A tool spindle on which a long tool of a predetermined length or longer and a standard tool shorter than the predetermined length are interchangeably mounted, A tool storage device capable of storing both the long tool and the standard tool, A tool changing device having a first tool gripping section and a second tool gripping section, for exchanging the long tool or the standard tool stored in the tool storage device with the mounted tool attached to the tool spindle, The device is characterized by comprising a tool exchange operation control unit that determines an operation pattern in a tool exchange operation using the tool exchange device, based on whether the mounting tool is the long tool or the standard tool, and whether the next tool to be mounted on the tool spindle is the long tool or the standard tool.

[0007] This machine tool includes a tool storage device capable of accommodating both the long tool and the standard tool, and a tool exchange operation control unit that determines the operation pattern during the tool exchange operation. Therefore, the machine tool can be made compact and inexpensive to perform the tool exchange operation.

[0008] The tool storage device may include a tool information storage unit that stores information distinguishing whether the tool stored in the tool storage device and the mounting tool are the long tool or the standard tool. The exchange operation control unit may control the machine tool to perform the tool exchange operation according to a determined operation pattern. The tool exchange device may grip the next mounting tool with one of the first tool gripping unit and the second tool gripping unit, and then grip the mounting tool with the other of the first tool gripping unit and the second tool gripping unit. The tool exchange operation is the operation of exchanging the long tool or the standard tool stored in the tool storage device with the mounting tool.

[0009] In this machine tool, The tool changing device has an arm pivot axis that rotates repeatedly within a predetermined angular range, The first tool gripping portion is formed to protrude radially from the arm pivot axis, and while gripping a standard tool and the arm pivot axis rotates repeatedly, the gripped standard tool does not interfere with the tool changing device. However, while gripping a long tool and the arm pivot axis rotates repeatedly, the gripped long tool moves within a range that causes it to interfere with the tool changing device. The second tool gripping portion is formed to protrude radially from the arm pivot axis, with a circumferential gap from the first tool gripping portion, and may move within a range in which the gripped standard tool and the long tool do not interfere with the tool changing device even when the arm pivot axis rotates repeatedly while gripping either the standard tool or the long tool.

[0010] Since the second tool gripping section moves within a range where no interference occurs regardless of whether it grips the standard tool or the long tool, it is easy to set an operation pattern that avoids interference.

[0011] Here, the tool changing device has an arm support that supports the arm pivot axis, the first tool gripping part grips the long tool and moves within a range in which the gripped long tool interferes with the arm support when the arm pivot axis rotates repeatedly, and the second tool gripping part grips either the normal tool or the long tool and moves within a range in which the gripped normal tool and the gripped long tool do not interfere with the arm support when the arm pivot axis rotates repeatedly.

[0012] In this machine tool, The replacement operation control unit may also control the gripping of the ordinary tool with the first tool gripping unit and the long tool with the second tool gripping unit when one of the mounting tool and the next mounting tool is the long tool and the other of the mounting tool and the next mounting tool is the ordinary tool.

[0013] Since the long tool is gripped by the second tool gripping section, interference between the long tool and the tool changing device can be avoided.

[0014] In this machine tool, The replacement operation control unit may, if both the next-to-be-mounted tool and the current-to-be-mounted tool are long tools, perform the following control: first, grip the current-to-be-mounted tool with the second tool gripping unit and remove it from the tool spindle; then, before storing the removed tool in the tool storage device, grip the next-to-be-mounted tool with the first tool gripping unit and remove it from the tool storage device, and mount the next-to-be-mounted tool on the tool spindle.

[0015] This allows for quick replacement while avoiding interference.

[0016] Here, the replacement operation control unit may also perform control to store the next-to-be-installed tool in the tool storage device after the next-to-be-installed tool has been mounted on the tool spindle.

[0017] The machine tool control method of the present invention, which solves the above problems, is: A control method for a machine tool comprising: a tool spindle on which a long tool of a predetermined length or longer and a standard tool shorter than the predetermined length are interchangeably mounted; a tool storage device capable of accommodating both the long tool and the standard tool; and a tool changing device for exchanging the long tool or standard tool stored in the tool storage device with a mounted tool attached to the tool spindle, An information acquisition step to acquire information on whether the mounting tool is the long tool or the standard tool, and information on whether the next mounting tool to be mounted on the tool spindle is the long tool or the standard tool, The system is characterized by having a replacement operation determination step, which determines the operation pattern of a tool replacement operation using the tool replacement device based on the information acquired in the information acquisition step.

[0018] According to the control method of this machine tool, since the tool storage device capable of storing both the long tool and the normal tool is provided, and the operation pattern in the tool change operation is determined in the change operation determination step, this machine tool can be configured to be small and inexpensive and execute the tool change operation.

Effect of the Invention

[0019] According to the present invention, it is possible to provide a machine tool and a control method for a machine tool that are inexpensive and can be miniaturized.

Brief Description of the Drawings

[0020] [Figure 1] It is a perspective view showing the main internal configuration of the machine tool according to this embodiment. [Figure 2] It is a perspective view showing a state where the tool changer shown in FIG. 1 holds a normal tool. [Figure 3] It is a perspective view similar to FIG. 2 showing a state where the tool changer shown in FIG. 1 holds a long tool. [Figure 4] It is a control block diagram of the machine tool shown in FIG. 1. [Figure 5] It is a flowchart showing steps S10 to S18 in the tool change operation. [Figure 6] It is a flowchart showing steps S19 to S27 in the tool change operation. [Figure 7] It is a flowchart showing steps S31 to S38 in the tool change operation. [Figure 8] It is a flowchart showing steps S39 to S45 in the tool change operation. ]> [Figure 9] It is a flowchart showing steps S51 to S58 in the tool change operation. [Figure 10] It is a flowchart showing steps S59 to S65 in the tool change operation. [Figure 11] It is a view showing a state where step S13 is completed. [Figure 12]This diagram shows the completed state of step S15. [Figure 13] This figure shows the completed state of step S18. [Figure 14] This figure shows the completed state of step S21. [Figure 15] This figure shows the completed state of step S26. [Figure 16] This figure shows the completed state of step S27. [Figure 17] This figure shows the completed state of step S31. [Figure 18] This figure shows the completed state of step S32. [Figure 19] This figure shows the completed state of step S35. [Figure 20] This figure shows the completed state of step S37. [Figure 21] This figure shows the completed state of step S39. [Figure 22] This figure shows the completed state of step S42. [Figure 23] This figure shows the completed state of step S44. [Figure 24] This figure shows the completed state of step S45. [Figure 25] This diagram shows the completed state of step S51. [Figure 26] This figure shows the completed state of step S52. [Figure 27] This diagram shows the completed state of step S55. [Figure 28] This diagram shows the completed state of step S57. [Figure 29] This figure shows the completed state of step S59. [Figure 30] This figure shows the completed state of step S62. [Figure 31] This figure shows the completed state of step S64. [Figure 32] This diagram shows the completed state of step S65. [Figure 33] This is a perspective view showing the tool storage device of the first modified example. [Figure 34] Figure 33 is a perspective view showing the removal of the tool pot (registered trademark) from the tool magazine. [Figure 35] Figure 33 is a cross-sectional view showing how a long tool is stored in the first-stage tool magazine of a machine tool equipped with the tool storage device shown. [Figure 36] This is a perspective view showing a tool storage device of the second modified example. [Figure 37] Figure 36 is a right side view of the tool storage device. [Figure 38] Figure 36 is a cross-sectional view showing how a long tool is stored in the first-stage tool magazine of a machine tool equipped with the tool storage device shown. [Modes for carrying out the invention]

[0021] Embodiments of the present invention will be described below with reference to the drawings.

[0022] Figure 1 is a perspective view showing the main internal configuration of the machine tool 1 according to this embodiment.

[0023] As shown in Figure 1, machine tool 1 is an NC (Numerical Control) lathe equipped with a spindle 2, a counter spindle 3, a tool spindle 4, a tool storage device 5, a tool changer 6, and a control device 7 (see Figure 4). The operation of these spindles 2, counter spindles 3, tool spindle 4, tool storage device 5, and tool changer 6 is controlled by the control device 7. The control device 7 is a computer that operates machine tool 1 according to an NC program or operations performed using an operation unit (not shown).

[0024] The spindle 2 grips a long, rod-shaped workpiece W inserted inside it in a manner that allows for release. The spindle 2 moves in the Z1 axis direction together with the gripped workpiece W. The Z1 axis direction is horizontal and, in Figure 1, is the direction connecting the upper left and lower right. The axes of the spindle 2 and the workpiece W coincide and are both in the Z1 axis direction. The spindle 2 rotates around its axis by driving a spindle motor (not shown), such as a built-in motor. As a result, the workpiece W gripped by the spindle 2 rotates around its axis.

[0025] The opposing spindle 3 grips the workpiece W, which has been cut by parting and transferred from the spindle 2, in a manner that allows for release. The opposing spindle 3 moves in the Z2 axis direction and the Y2 axis direction together with the gripped workpiece W. The Z2 axis direction is the same direction as the Z1 axis direction described above. The Y2 axis direction is horizontal and perpendicular to the Z2 axis direction. The axis direction of the opposing spindle 3 coincides with the axis direction of the spindle 2 and also coincides with the axis direction of the workpiece W gripped by the opposing spindle 3. The opposing spindle 3 rotates around its axis by driving a spindle motor (not shown), such as a built-in motor. As a result, the workpiece W gripped by the opposing spindle 3 rotates around its axis.

[0026] The tool spindle 4 moves in the X3, Y3, and Z3 axes. Furthermore, the tool spindle 4 rotates along the B axis with the Y3 axis as the pivot point. The X3 axis is vertical. The Y3 axis is the same direction as the Y2 direction described above. The Z3 axis is the same direction as the Z1 and Z2 axes described above. Hereinafter, movement of the tool spindle 4 along the Y3 axis toward the lower left in Figure 1 will be referred to as +Y3 movement, and movement of the tool spindle 4 along the Y3 axis toward the upper right in Figure 1 will be referred to as -Y3 movement. Similarly, movement of the tool spindle 4 along the Z3 axis toward the lower right in Figure 1 will be referred to as +Z3 movement, and movement of the tool spindle 4 along the Z3 axis toward the upper left in Figure 1 will be referred to as -Z3 movement. The movement of the tool spindle 4 in the X3, Y3, and Z3 axes, as well as rotation along the B axis, are performed by a servo motor (not shown).

[0027] The tool spindle 4 is equipped with interchangeable tools such as drills and end mills for machining the workpiece W. Hereinafter, the tool mounted on the tool spindle 4 may be referred to as the mounted tool T1. The tools that the tool spindle 4 can mount include long tools TL with a length greater than a predetermined length and standard tools TS that are shorter than a predetermined length. Standard tools TS are tools used for general machining. Long tools TL are tools used for special machining, such as gun drills. Figure 1 shows the tool spindle 4 with a standard tool TS mounted on it. Hereinafter, when standard tools TS and long tools TL are not distinguished, they may simply be referred to as tools. The tool spindle 4 has a tool spindle motor 41 that rotates the mounted tool T1. The mounted tool T1 rotates when the tool spindle motor 41 is driven. Regardless of whether the workpiece W is held on the spindle 2 or the opposing spindle 3, it can be machined by the mounted tool T1 by moving the tool spindle 4 in each axial direction or rotating along the B axis.

[0028] The tool storage device 5 has a support column 51 and two tool magazines 52. The support column 51 is fixed to the frame of the machine tool 1. The tool magazines 52 are rotatably supported on the support column 51. The tool magazines 52 have a magazine body 520 and tool pots 521. The magazine body 520 is made of metal and is wheel-shaped, with a central hub and an annular portion forming the outer circumference connected by six spokes. Multiple tool pots 521 are arranged circumferentially on the annular portion of the magazine body 520. Each of these tool pots 521 stores one standard tool TS or long tool TL for mounting on the tool spindle 4. The two tool magazines rotate around their central axis by driving a magazine motor 53 (see Figure 11(b)). Figure 1 shows the tool storage device 5 with two tool magazines 52: a first-stage tool magazine 52 located on the support column 51 side and a second-stage tool magazine 52 located spaced apart from the support column 51. These two tool magazines 52 are connected by screws with their central axes aligned. Tools are stored in the tool magazines 52 with the shank facing the support column 51 and the tip facing the opposite side of the support column 51. Therefore, the second tool magazine 52 is positioned towards the tip of the tool stored in the first tool magazine 52. The first tool magazine 52 can normally store standard tools TS, while the second tool magazine 52 is configured to store both standard tools TS and long tools TL. The distance between the first and second tool magazines 52 can be increased to allow the first tool magazine 52 to store long tools TL.

[0029] In this embodiment of the machine tool 1, the long tool TL cannot be stored in the first-stage tool magazine 52 because attempting to store the long tool TL in the first-stage tool magazine 52 would cause interference between the annular portion of the second-stage tool magazine 52 and the long tool TL. However, if the number of tools T is sufficient with just the first-stage tool magazine 52, the second-stage tool magazine 52 may be omitted. In that case, both standard tools TS and long tools TL can be stored in the first-stage tool magazine 52.

[0030] The tool changer 6 is a device for exchanging a tool stored in the tool storage device 5 with a tool T1 mounted on the tool spindle 4. This tool changer 6 has a first moving mechanism 61, a second moving mechanism 62, an arm support 63, and a tool changer arm 64. The first moving mechanism 61 has a Z-axis motor 611 for moving the second moving mechanism 62, the arm support 63, and the tool changer arm 64 in the Z-axis direction. The Z-axis direction is the same direction as the Z1-axis direction, Z2-axis direction, and Z3-axis direction described above. Hereinafter, when the tool changer arm 64 moves toward the lower right in Figure 1 along the Z-axis direction, it will be referred to as +Z movement, and when the tool changer arm 64 moves toward the upper left in Figure 1 along the Z-axis direction, it will be referred to as -Z movement.

[0031] The second movement mechanism 62 has a drive cylinder 621 for moving the arm support 63 and the tool changing arm 64 in the Y-axis direction. The Y-axis direction is the same direction as the Y2-axis direction and Y3-axis direction described above. Hereinafter, when the tool changing arm 64 moves along the Y-axis direction toward the lower left in Figure 1, it will be referred to as +Y movement, and when the tool changing arm 64 moves along the Y-axis direction toward the upper right in Figure 1, it will be referred to as -Y movement.

[0032] The arm support 63 rotatably supports the tool changing arm 64. The arm support 63 includes a Y-axis moving base 631, an arm cylinder 632, and an arm motor 633. The Y-axis moving base 631 is connected to a drive cylinder 621 and moves in the Y-axis direction by receiving the driving force of the drive cylinder 621. The arm cylinder 632 is a cylindrical body fixed to the lower end of the Y-axis moving base 631. The arm motor 633 is a motor for repeatedly rotating the tool changing arm 64 within a predetermined angular range. By driving the arm motor 633, the tool changing arm 64 rotates around the arm central axis extending in the Z-axis direction as the pivot point.

[0033] The tool change arm 64 grips the mounting tool T1 attached to the tool spindle 4 or the tool stored in the tool storage device 5 and moves in the Z-axis and Y-axis directions. The tool stored in this tool storage device 5 is an example of a stored tool. Figure 1 shows the tool change arm 64 normally gripping the tool TS and waiting in the exchange position for exchanging the tool with the tool spindle 4.

[0034] Figure 2 is a perspective view showing the tool changing device 6 shown in Figure 1 in the normal state of gripping a tool TS. Figure 2 shows the lower part of the arm support 63 and the tool changing arm 64.

[0035] As shown in Figure 2, the tool changing arm 64 has an arm pivot shaft 641, a first tool gripping portion 642, and a second tool gripping portion 643. Figure 2 shows the first tool gripping portion 642 and the second tool gripping portion 643 each gripping a normal tool TS. The arm pivot shaft 641 is composed of a shaft portion 6411 and a gripping base portion 6412. The shaft portion 6411 is cylindrical with its axial direction in the Z-axis direction. The shaft portion 6411 is rotatably held inside the arm cylinder 632. One end of the shaft portion 6411 is connected to the output shaft of the arm motor 633. The gripping base portion 6412 is fixed to the other end of the shaft portion 6411.

[0036] The first tool gripping portion 642 has its base fixed to the gripping base portion 6412 and protrudes radially from the gripping base portion 6412 toward the arm pivot axis 641. The protruding end portion of the first tool gripping portion 642 is provided with a pair of gripping claws for gripping a tool. The pair of gripping claws are displaceable in a direction in which the protruding ends move toward and away from each other. The pair of gripping claws are biased by a spring (not shown) in a direction in which the protruding ends move toward each other, and when no external force is applied, the protruding ends of the pair of gripping claws are maintained at a predetermined distance apart.

[0037] The second tool gripping portion 643 protrudes radially from the gripping base 6412 around the arm pivot axis 641 at a position rotated 90 degrees relative to the first tool gripping portion 642 around the axial direction of the arm pivot axis 641. The first tool gripping portion 642 and the second tool gripping portion 643 are positioned at the same location in the Z-axis direction. The second tool gripping portion 643 has the same configuration as the first tool gripping portion 642 except for its protruding direction, and a pair of gripping claws for gripping the tool are provided at the protruding end. When exchanging the tool taken out of the tool storage device 5 with the mounted tool T1 attached to the tool spindle 4, the rotation angle of the arm pivot axis 641 is equal to the angle difference between the protruding direction of the first tool gripping portion 642 and the protruding direction of the second tool gripping portion 643, and is the angle at which the tool exchange arm 64 rotates repeatedly. The circumferential angle difference between the first tool gripping portion 642 and the second tool gripping portion 643 may be 90 degrees or more, or it may be 90 degrees or less.

[0038] Figure 2(a) shows the first position in which the first tool gripping portion 642 protrudes in the -Y direction and the second tool gripping portion 643 protrudes downward. This downward direction is the same as the +X3 direction of the tool spindle 4 and can be said to be the +X direction in the tool changer 6. Figure 2(b) shows the second position in which the tool changer arm 64 is rotated 90 degrees clockwise when viewed in the +Z direction relative to Figure 2(a). In this second position, the first tool gripping portion 642 protrudes upward and the second tool gripping portion 643 protrudes in the -Y direction. This upward direction is the same as the -X3 direction of the tool spindle 4 and can be said to be the -X direction in the tool changer 6. The tool changer arm 64 rotates repeatedly between the first position shown in Figure 2(a) and the second position shown in Figure 2(b). The angular range between this first and second position corresponds to an example of a predetermined angular range. In this embodiment, an example with an angular range of 90 degrees is shown, but this angular range is set appropriately in accordance with the angle between the protruding direction of the first tool gripping part 642 and the protruding direction of the second tool gripping part 643. As shown in Figures 2(a) and 2(b), even when the first tool gripping part 642 and the second tool gripping part 643 each grip the normal tool TS and the tool changing arm 64 rotates to change its position between the first and second positions, the normal tool TS does not interfere with the tool changing device 6.

[0039] Figure 3 is a perspective view similar to Figure 2, showing the tool changing device 6 shown in Figure 1 gripping the long tool TL.

[0040] Figure 3(a) shows the first tool gripping section 642 and the second tool gripping section 643 each gripping the long tool TL in the first position. As shown in Figure 3(a), even though the first tool gripping section 642 and the second tool gripping section 643 each grip the long tool TL, there is no interference between the long tool TL and the tool changer 6 in the first position. However, as shown in Figure 3(b), in the second position, when the first tool gripping section 642 and the second tool gripping section 643 each grip the long tool TL, the long tool TL gripped by the first tool gripping section 642 interferes with the tool changer 6 (arm support section 63). In Figure 3(b), the interfering area is shown with cross-hatching. In reality, when changing posture from the first posture to the second posture, the long tool TL gripped by the first tool gripping part 642 interferes with the arm support part 63 while the first tool gripping part 642 is moving. That is, the first tool gripping part 642 moves within a range where, even when gripping a normal tool TS and the arm rotation axis 641 rotates repeatedly within a predetermined angular range, the gripped normal tool TS does not interfere with the arm support part 63, but when gripping a long tool TL and the arm rotation axis 641 rotates repeatedly, the gripped long tool TL interferes with the arm support part 63. On the other hand, the second tool gripping part 643 moves within a range where neither the gripped normal tool TS nor the long tool TL interferes with the arm support part 63, regardless of whether the gripped tool is a normal tool TS or a long tool TL, and the arm rotation axis 641 rotates repeatedly within a predetermined angular range.

[0041] Figure 4 is a control block diagram of the machine tool 1 shown in Figure 1. Although Figure 4 shows only the control configurations that are particularly relevant to this embodiment, the control device 7 also controls other components of the machine tool 1 that are not shown in Figure 4.

[0042] As shown in Figure 4, the control device 7 includes a storage means 71 and an exchange operation control unit 72. The storage means 71 includes an NC program storage unit 711 and a tool information storage unit 712. This storage means 71 is composed of a non-volatile memory and a volatile memory. The NC program storage unit 711 stores the NC program created by the operator of the machine tool 1. The control device 7 controls the various actuators and other components of the machine tool 1 according to this NC program.

[0043] The tool information storage unit 712 stores tool information such as tool type and tool length for all tools stored in the tool storage device 5 and for each mounted tool T1. One of this tool information items is information that distinguishes between a standard tool TS and a long tool TL. Alternatively, instead of storing information on whether a tool is a standard tool TS or a long tool TL, a length threshold may be stored, and the system may determine whether a tool is a standard tool TS or a long tool TL based on that length threshold and the tool length information stored in the tool information storage unit 712.

[0044] The tool change operation control unit 72 controls the operation of the tool spindle 4, tool storage device 5, and tool change device 6 during tool change. The tool change operation control unit 72 obtains information from the tool information storage unit 712 regarding whether the currently mounted tool T1 (see Figure 1) on the tool spindle 4 and the next tool to be mounted T2 (see Figure 11), which is specified in the NC program as the next tool to be mounted on the tool spindle 4, are standard tools TS or long tools TL. Based on whether the mounted tool T1 is a long tool TL or a standard tool TS, and whether the next tool to be mounted T2 is a long tool TL or a standard tool TS, the control unit 72 determines the operation pattern of the machine tool 1 during the tool change operation. The operation of determining the operation pattern by the tool change operation control unit 72 and the tool change operation based on the determined operation pattern are explained below using a flowchart.

[0045] The tool change operation in machine tool 1 will be explained below using the flowcharts in Figures 5-10 and the plan and right side views in Figures 11-32. In the explanation of the tool change operation, an example will be shown in which the next tool to be installed T2 is taken out of the second-stage tool magazine 52 and the used tool removed from the tool spindle 4 is stored in the second-stage tool magazine 52. The explanation of the next tool to be installed T2 is omitted, as is the example of taking out the next tool to be installed T2 from the first-stage tool magazine 52 and storing the used tool removed from the tool spindle 4 in the first-stage tool magazine 52.

[0046] Figures 5-10 are flowcharts illustrating the tool change operation. This tool change operation is performed by the control device 7 operating the machine tool 1 according to the NC program.

[0047] As shown in Figure 5, first, the replacement operation control unit 72 obtains from the tool information storage unit 712 information on whether the next tool to be mounted T2 is a standard tool TS or a long tool TL, and whether the mounted tool T1 is a standard tool TS or a long tool TL (step S10). This step S10 corresponds to an example of an information acquisition process. In step S10, only the information on whether the next tool to be mounted T2 is a standard tool TS or a long tool TL may be obtained, and a step to obtain information on whether the mounted tool T1 is a standard tool TS or a long tool TL may be provided between steps S11 and S12. In this case, the step to obtain the information between steps S11 and S12 also corresponds to an example of an information acquisition process.

[0048] Next, the tool change operation control unit 72 determines whether the next tool to be mounted T2 is a long tool TL based on the information acquired in step S10 (step S11). If the next tool to be mounted T2 is a long tool TL (YES in step S11), the tool change operation control unit 72 determines whether the mounted tool T1 currently mounted on the tool spindle 4 is a long tool TL based on the information acquired in step S10 (step S12). Steps S11 and S12 correspond to an example of the operation pattern determination process. If both the next tool to be mounted T2 and the mounted tool T1 are long tools TL (YES in step S12), the tool change operation control unit 72 determines the operation pattern of the tool change device 6 to the operation pattern of steps S13 to S27 described below. Hereinafter, this operation pattern of steps S13 to S27 may be referred to as the first operation pattern.

[0049] In the first operation pattern, while the machine tool 1 is performing machining using the mounted tool T1, the tool exchange operation control unit 72 moves the tool exchange arm 64 to the exchange position where the tool is exchanged with the tool spindle 4 (step S13). In this movement in step S13, the tool exchange operation control unit 72 moves the tool exchange arm 64 to the exchange position while changing the posture of the tool exchange arm 64 to a second posture in which the second tool gripping portion 643 protrudes in the -Y direction.

[0050] Figure 11(a) is a plan view showing the completed step S13, and Figure 11(b) is a right side view of Figure 11(a). In the diagrams illustrating the tool change operation, for the sake of clarity, tools other than the currently installed tool T1, the next tool to be installed T2, and the tool immediately after being removed from the tool spindle 4 and stored in the tool magazine 52 are omitted from the illustration. Furthermore, in the diagrams illustrating the tool change operation, only the second-stage tool magazine 52 of the tool storage device 5 is shown, and in the plan view, tool pots 521 other than the tool pot 521 in a transferable position and the first moving mechanism 61 are omitted from the illustration. In addition, in the diagrams illustrating the tool change operation, the tool spindle 4 is omitted from the illustration when its relationship to the operation of the tool spindle 4 is low.

[0051] As shown in Figures 11(a) and 11(b), the tool exchange arm 64, which is waiting in the exchange position, is in a second position where the first tool gripping part 642 protrudes upward and the second tool gripping part 643 protrudes in the -Y direction. At this time, neither the first tool gripping part 642 nor the second tool gripping part 643 is gripping a tool. The exchange operation control unit 72 rotates the tool magazine 52 to position the next tool to be installed T2 at the position furthest to the +Y side in the tool magazine 52. This position furthest to the +Y side is the position where the next tool to be installed T2 can be handed over to the tool exchange device 6.

[0052] Once step S13 is complete, the tool change control unit 72 makes the tool change device 6 wait until machining using the tool T1 mounted on the tool spindle 4 is complete (step S14). Once machining using the tool T1 is complete (YES in step S14), the tool change control unit 72 moves the tool spindle 4, with the tip of the tool T1 pointed in the +Z3 direction, by +Z3 to bring it closer to the tool change arm 64, and then moves the tool spindle 4 by +Y3 to the tool change position. As a result, the second tool gripping unit 643 grips the tool T1 (step S15). Figure 12(a) is a plan view showing the state after step S15 is completed, and Figure 12(b) is a right side view of Figure 12(a). During the +Y3 movement of the tool spindle 4 in step S15, the gripped portion of the mounted tool T1 comes into contact with the protruding end of the gripping claw of the second tool gripping portion 643, pushing the protruding end apart and allowing the gripped portion of the mounted tool T1 to enter between the pair of gripping claws. Then, as the tool spindle 4 moves further +Y3, the gripped portion is positioned in the +Y direction relative to the protruding end of the gripping claw, and the mounted tool T1 is gripped by the second tool gripping portion 643 as shown in Figures 12(a) and 12(b).

[0053] Once the second tool gripping unit 643 has finished gripping the mounting tool T1, the replacement operation control unit 72 unclams the mounting tool T1 and moves the tool spindle 4 -Z3 (step S16). In this way, the mounting tool T1 is removed from the tool spindle 4. Then, a gap is formed in the Z-axis direction between the tip of the tool spindle 4 and the removed used tool.

[0054] Next, the exchange operation control unit 72 rotates the arm pivot axis 641 to change the position to the first position while moving the tool exchange arm 64 by +Z (step S17). As a result of step S17, the second tool gripping part 643, which is holding the used tool, is positioned to protrude downward. The first tool gripping part 642 also protrudes in the -Y direction and is positioned opposite the part to be gripped of the next tool to be installed T2.

[0055] Subsequently, the tool exchange operation control unit 72 moves the tool exchange arm 64 -Y to allow the first tool gripping unit 642 to grip the next tool to be installed T2 (step S18). Figure 13(a) is a plan view showing the completed state of step S18, and Figure 13(b) is a right side view of the same figure (a). As shown in Figures 13(a) and 13(b), in step S18, the drive cylinder 621 moves the arm support unit 63 in the -Y direction, causing the tool exchange arm 64 to move -Y together with the arm support unit 63. During this -Y movement, the part of the next tool to be installed T2 comes into contact with the protruding end of the gripping claw of the first tool gripping unit 642, pushing the protruding end open and allowing the part of the next tool to be installed T2 to enter between the pair of gripping claws. Then, as the tool exchange arm 64 moves -Y further, the next tool to be installed T2 is gripped by the first tool gripping unit 642.

[0056] Once the first tool gripping unit 642 grips the next tool to be installed T2, the replacement operation control unit 72 moves the tool replacement arm 64 +Z (step S19). As the tool replacement arm 64 moves +Z, the next tool to be installed T2, which was gripped by the first tool gripping unit 642, is removed from the tool pot 521 of the tool magazine 52.

[0057] After step S19, the exchange operation control unit 72 moves the tool exchange arm 64 in the +Y direction to retract it from the tool magazine 52 (step S20). In step S20, the drive cylinder 621 moves the arm support 63 in the +Y direction, causing the tool exchange arm 64 to move in the +Y direction along with the arm support 63.

[0058] Once step S20 is complete, the tool exchange operation control unit 72 moves the tool exchange arm 64 -Z to the tool exchange position (step S21). Figure 14(a) is a plan view showing the state after step S21 is completed, and Figure 14(b) is a right side view of Figure 14(a). As shown in Figures 14(a) and 14(b), the tool exchange arm 64 is stopped in the exchange position with the first tool gripping portion 642, which is gripping the next tool to be installed T2, protruding in the -Y direction.

[0059] Next, the exchange operation control unit 72 moves the tool spindle 4 by +Z3 (step S22). As a result, the shank of the next tool to be installed T2, which is held by the first tool gripping unit 642, is inserted into the tool spindle 4 towards the tip.

[0060] Once step S22 is complete, the exchange operation control unit 72 clamps the next tool to be mounted T2 to the tool spindle 4, then moves the tool spindle 4 -Y3 to retract it from the tool exchange position (step S23). As a result, the next tool to be mounted T2 is mounted to the tool spindle 4, and the grip of the next tool to be mounted T2 by the first tool gripping unit 642 is released. In this first operation pattern, where both the mounted tool T1 and the next tool to be mounted T2 are long tools TL, the tool exchange arm 64 is not rotated while the next tool to be mounted T2 is gripped by the first tool gripping unit 642, so there is no interference between the long tool TL and the arm support unit 63. Furthermore, in this first operation pattern, after the second tool gripping part 643 grips the mounting tool T1 and removes it from the tool spindle 4, and before storing the removed used tool in the tool storage device 5, the first tool gripping part 642 grips the next mounting tool T2, takes it out of the tool storage device 5, and mounts it on the tool spindle 4, thus enabling quick replacement.

[0061] Subsequently, the tool exchange control unit 72 initiates machining using the newly mounted tool on the tool spindle 4. Meanwhile, the tool exchange control unit 72 rotates the arm pivot axis 641 to change its position to the second position while moving the tool exchange arm 64 in the +Z direction (step S24). As a result of step S24, the first tool gripping part 642, which is not gripping a tool, is positioned to protrude upward. The second tool gripping part 643 is positioned to protrude in the -Y direction, and the used tool removed from the tool spindle 4 is positioned slightly closer to the +Z direction than the tool pot 521 in the tool magazine 52.

[0062] Next, the exchange operation control unit 72 moves the tool exchange arm 64 -Y (step S25). As a result, the used tool held by the second tool gripping unit 643 is positioned so that there is a small gap in the Z-axis direction between it and the tool pot 521 located on the +Y side of the tool magazine 52, with the shank of the used tool facing the tool pot 521.

[0063] After step S25, the tool exchange operation control unit 72 moves the tool exchange arm 64 -Z (step S26). Figure 15(a) is a plan view showing the state after step S26 is completed, and Figure 15(b) is a right side view of Figure 15(a). As shown in Figures 15(a) and 15(b), as the tool exchange arm 64 moves -Z, the used tool held by the second tool gripping unit 643 is inserted into the tool pot 521 located furthest to the +Y side of the tool magazine 52 and stored in the tool magazine 52.

[0064] Subsequently, the tool exchange operation control unit 72 moves the tool exchange arm 64 +Y (step S27). Figure 16(a) is a plan view showing the state after step S27 is completed, and Figure 16(b) is a right side view of the same figure (a). As shown in Figures 16(a) and 16(b), when the tool exchange arm 64 moves +Y, the grip of the used tool by the second tool gripping unit 643 is released, and the tool exchange arm 64 moves away from the tool magazine 52. Once step S27 is completed, the tool exchange operation according to the first operation pattern is finished.

[0065] In step S11, if it is determined that the next tool to be installed T2 is not a long tool TL (NO in step S11), the tool change operation control unit 72 determines the operation pattern of the tool change device 6 to the operation pattern of steps S31 to S45 described below. Hereinafter, this operation pattern of steps S31 to S45 may be referred to as the second operation pattern.

[0066] In the second operation pattern, the exchange operation control unit 72 rotates the arm pivot axis 641 to the first position while moving the tool exchange arm 64 +Z (step S31). Simultaneously or before this, the exchange operation control unit 72 positions the next tool to be installed T2 at the position furthest to +Y in the tool magazine 52. This next tool to be installed T2 is a standard tool TS, as it was determined in step S11 not to be a long tool TL. Figure 17(a) is a plan view showing the state after step S31 is completed, and Figure 17(b) is a right side view of Figure 17(a). As shown in Figures 17(a) and 17(b), step S31 causes the second tool gripping part 643 to protrude downward. The first tool gripping part 642 also protrudes in the -Y direction and is positioned opposite the gripped part of the next tool to be installed T2.

[0067] Subsequently, the tool exchange operation control unit 72 moves the tool exchange arm 64 -Y to allow the first tool gripping unit 642 to grip the next tool to be installed T2 (step S32). Figure 18(a) is a plan view showing the completed state of step S32, and Figure 18(b) is a right side view of the same figure (a). As shown in Figures 18(a) and 18(b), the first tool gripping unit 642 grips the next tool to be installed T2 as the tool exchange arm 64 moves -Y.

[0068] Once the first tool gripping unit 642 grips the next tool to be installed T2, the replacement operation control unit 72 moves the tool replacement arm 64 +Z (step S33). As the tool replacement arm 64 moves +Z, the next tool to be installed T2, which was gripped by the first tool gripping unit 642, is removed from the tool pot 521 of the tool magazine 52.

[0069] After step S33, the tool exchange operation control unit 72 moves the tool exchange arm 64 in the +Y direction (step S34). Subsequently, the tool exchange operation control unit 72 rotates the arm pivot axis 641 to change its posture to the second posture and moves the tool exchange arm 64 in the -Z direction to the tool exchange position (step S35). Figure 19(a) is a plan view showing the state after step S35 is completed, and Figure 19(b) is a right side view of Figure 19(a). As shown in Figures 19(a) and 19(b), the tool exchange arm 64 is in a second posture in which the first tool gripping part 642, which is gripping the next tool to be installed T2, is protruding upward, and the second tool gripping part 643, which is not gripping a tool, is protruding in the -Y direction. Note that Figures 19 to 24 show an example in which the installed tool T1 is a normal tool TS, but the installed tool T1 in the second operation pattern may be a long tool TL.

[0070] Once step S35 is complete, the tool change control unit 72 makes the tool change device 6 wait until machining using the tool T1 mounted on the tool spindle 4 is complete (step S36). Once machining using the tool T1 is complete (YES in step S36), the tool change control unit 72 moves the tool spindle 4, with the tip of the tool T1 pointed in the +Z3 direction, by +Z3 to bring it closer to the tool change arm 64, and then moves the tool spindle 4 by +Y3 to the tool change position. As a result, the second tool gripping unit 643 grips the tool T1 (step S37). Figure 20(a) is a plan view showing the state after step S37 is completed, and Figure 20(b) is a right side view of Figure 20(a). As shown in Figures 20(a) and 20(b), as the tool spindle 4 moves +Y3, the part of the mounting tool T1 to be gripped enters between the pair of gripping claws, and the mounting tool T1 is gripped by the second tool gripping part 643.

[0071] Once the second tool gripping unit 643 has finished gripping the mounting tool T1, the replacement operation control unit 72 unclams the mounting tool T1 and moves the tool spindle 4 -Z3 (step S38). In this way, the mounting tool T1 is removed from the tool spindle 4. Then, a gap is formed in the Z-axis direction between the tip of the tool spindle 4 and the removed used tool.

[0072] Once the -Z3 movement of the tool spindle 4 is complete, the exchange operation control unit 72 rotates the arm pivot axis 641 to change its position to the first position (step S39). Figure 21(a) is a plan view showing the state after step S39 is completed, and Figure 21(b) is a right side view of Figure 21(a). As shown in Figures 21(a) and 21(b), the tool exchange arm 64 is in a first position where the first tool gripping part 642, which grips the next tool to be installed T2, protrudes in the -Y direction, and the second tool gripping part 643, which grips the used tool removed from the tool spindle 4, protrudes downward. In this second operation pattern, where the next tool to be installed T2 is a normal tool TS, even if the tool exchange arm 64 is rotated with the next tool to be installed T2 gripped by the first tool gripping part 642, the next tool to be installed T2 and the arm support part 63 will not interfere with each other.

[0073] Next, the exchange operation control unit 72 moves the tool spindle 4 by +Z3 (step S40). As a result, the shank of the next tool to be installed T2, which is held by the first tool gripping unit 642, is inserted into the tool spindle 4 towards the tip.

[0074] Once step S40 is complete, the replacement operation control unit 72 clamps the next tool to be mounted T2 to the tool spindle 4 and then moves the tool spindle 4 -Y3 (step S41). As a result, the next tool to be mounted T2 is mounted to the tool spindle 4 and the grip of the next tool to be mounted T2 by the first tool gripping unit 642 is released.

[0075] Subsequently, the tool exchange operation control unit 72 initiates machining using the newly mounted tool on the tool spindle 4. Meanwhile, the tool exchange operation control unit 72 rotates the arm pivot axis 641 to change its posture to the second position while moving the tool exchange arm 64 in the +Z direction (step S42). Figure 22(a) is a plan view showing the state after step S42 is completed, and Figure 22(b) is a right side view of Figure 22(a). As shown in Figures 22(a) and 22(b), the tool exchange arm 64 is in a position where the first tool gripping portion 642, which does not grip a tool, protrudes upward, and the used tool removed from the tool spindle 4 is gripped by the second tool gripping portion 643, which protrudes in the -Y direction, and is positioned slightly closer to the +Z direction than the tool pot 521 of the tool magazine 52.

[0076] Next, the exchange operation control unit 72 moves the tool exchange arm 64 -Y (step S43). As a result, the used tool held by the second tool gripping unit 643 is positioned with a small gap in the Z-axis direction between it and the tool pot 521 located furthest to the +Y side of the tool magazine 52, with the shank of the used tool facing the tool pot 521.

[0077] After step S43, the tool exchange operation control unit 72 moves the tool exchange arm 64 -Z (step S44). Figure 23(a) is a plan view showing the state after step S44 is completed, and Figure 23(b) is a right side view of Figure 23(a). As shown in Figures 23(a) and 23(b), as the tool exchange arm 64 moves -Z, the used tool held by the second tool gripping unit 643 is inserted into the tool pot 521 located furthest to the +Y side of the tool magazine 52 and stored in the tool magazine 52.

[0078] Subsequently, the tool exchange operation control unit 72 moves the tool exchange arm 64 in the +Y direction (step S45). Figure 24(a) is a plan view showing the state after step S45 is completed, and Figure 24(b) is a right side view of the same figure (a). As shown in Figures 24(a) and 24(b), the +Y movement of the tool exchange arm 64 releases the grip of the used tool by the second tool gripping unit 643, and the tool exchange arm 64 moves away from the tool magazine 52. Once step S45 is completed, the tool exchange operation according to the second operation pattern is finished.

[0079] In step S12, if it is determined that the next tool to be installed T2 is not a long tool TL (NO in step S12), the tool change operation control unit 72 determines the operation pattern of the tool change device 6 to the operation pattern of steps S51 to S65 described below. Hereinafter, this operation pattern of steps S51 to S65 may be referred to as the third operation pattern.

[0080] In the third operation pattern, the exchange operation control unit 72 rotates the arm pivot axis 641 to the second position while moving the tool exchange arm 64 +Z (step S51). Simultaneously or before this, the exchange operation control unit 72 positions the next tool to be installed T2 at the position furthest to +Y in the tool magazine 52. This next tool to be installed T2 is the tool that was determined to be a long tool TL in step S11, and is therefore a long tool TL. Figure 25(a) is a plan view showing the state after step S31 is completed, and Figure 25(b) is a right side view of Figure 25(a). As shown in Figures 25(a) and 25(b), in step S51, the second tool gripping part 643 is in a position protruding in the -Y direction and positioned opposite the gripped part of the next tool to be installed T2. The first tool gripping part 642 is in a position protruding upward.

[0081] Subsequently, the tool exchange operation control unit 72 moves the tool exchange arm 64 -Y to allow the second tool gripping unit 643 to grip the next tool to be installed T2 (step S52). Figure 26(a) is a plan view showing the state after step S32 has been completed, and Figure 26(b) is a right side view of the same figure (a). As shown in Figures 26(a) and 26(b), the second tool gripping unit 643 grips the next tool to be installed T2 as the tool exchange arm 64 moves -Y.

[0082] Once the second tool gripping unit 643 grips the next tool to be installed T2, the replacement operation control unit 72 moves the tool replacement arm 64 +Z (step S53). As the tool replacement arm 64 moves +Z, the next tool to be installed T2, which was gripped by the second tool gripping unit 643, is removed from the tool pot 521 of the tool magazine 52.

[0083] After step S53, the tool exchange operation control unit 72 moves the tool exchange arm 64 in the +Y direction (step S54). Subsequently, the tool exchange operation control unit 72 rotates the arm pivot axis 641 to change its posture to the first posture and moves the tool exchange arm 64 in the -Z direction to the tool exchange position (step S55). Figure 27(a) is a plan view showing the state after step S55 is completed, and Figure 27(b) is a right side view of Figure 27(a). As shown in Figures 27(a) and 27(b), the tool exchange arm 64 is in a posture where the first tool gripping portion 642, which is not gripping a tool, is protruding in the -Y direction, and the second tool gripping portion 643, which is gripping the next tool to be installed T2, is protruding downwards.

[0084] Once step S55 is complete, the tool change control unit 72 makes the tool change device 6 wait until machining using the tool T1 mounted on the tool spindle 4 is complete (step S56). Once machining using the tool T1 is complete (YES in step S56), the tool change control unit 72 moves the tool spindle 4, with the tip of the tool T1 pointed in the +Z3 direction, by +Z3 to bring it closer to the tool change arm 64, and then moves the tool spindle 4 by +Y3 to the tool change position. As a result, the first tool gripping unit 642 grips the tool T1 (step S57). Figure 28(a) is a plan view showing the state after step S57 is complete, and Figure 28(b) is a right side view of Figure 28(a). As shown in Figures 28(a) and 28(b), as the tool spindle 4 moves +Y3, the part of the mounting tool T1 to be gripped enters between the pair of gripping claws, and the mounting tool T1 is gripped by the first tool gripping part 642.

[0085] Once the first tool gripping unit 642 has finished gripping the mounting tool T1, the replacement operation control unit 72 unclams the mounting tool T1 and moves the tool spindle 4 -Z3 (step S58). In this way, the mounting tool T1 is removed from the tool spindle 4. Then, a gap is formed in the Z-axis direction between the tip of the tool spindle 4 and the removed used tool.

[0086] Once the -Z3 movement of the tool spindle 4 is complete, the exchange operation control unit 72 rotates the arm pivot axis 641 to change its position to the second position (step S59). Figure 29(a) is a plan view showing the state after step S59 is completed, and Figure 29(b) is a right side view of Figure 29(a). As shown in Figures 29(a) and 29(b), the tool exchange arm 64 is in a first position where the first tool gripping part 642, which grips the used tool removed from the tool spindle 4, is protruding upward, and the second tool gripping part 643, which grips the next tool to be installed T2, is protruding in the -Y direction. In this third operation pattern, the used tool T1, which is the normal tool TS, is gripped by the first tool gripping part 642, and the next tool to be installed T2, which is the long tool TL, is gripped by the second tool gripping part 643. Therefore, even if the tool change arm 64 is rotated, the long tool TL and the arm support part 63 will not interfere with each other.

[0087] Next, the exchange operation control unit 72 moves the tool spindle 4 by +Z3 (step S60). As a result, the shank of the next tool to be installed T2, which is held by the second tool gripping unit 643, is inserted into the tool spindle 4 towards the tip.

[0088] Once step S60 is complete, the replacement operation control unit 72 clamps the next tool to be mounted T2 to the tool spindle 4 and then moves the tool spindle 4 -Y3 (step S61). As a result, the next tool to be mounted T2 is mounted to the tool spindle 4 and the grip of the next tool to be mounted T2 by the second tool gripping unit 643 is released.

[0089] Subsequently, the tool exchange operation control unit 72 initiates machining using the newly mounted tool on the tool spindle 4. Meanwhile, the tool exchange operation control unit 72 rotates the arm pivot axis 641 to change its position to the first position while moving the tool exchange arm 64 in the +Z direction (step S62). Figure 30(a) is a plan view showing the state after step S62 is completed, and Figure 30(b) is a right side view of Figure 30(a). As shown in Figures 30(a) and 30(b), the tool exchange arm 64 is in a position where the second tool gripping portion 643, which does not grip a tool, protrudes downward, and the used tool removed from the tool spindle 4 is gripped by the first tool gripping portion 642, which protrudes in the -Y direction, and is positioned slightly closer to the +Z direction than the tool pot 521 of the tool magazine 52.

[0090] Next, the exchange operation control unit 72 moves the tool exchange arm 64 -Y (step S63). As a result, the used tool held by the second tool gripping unit 643 is positioned so that there is a small gap in the Z-axis direction between it and the tool pot 521 located on the +Y side of the tool magazine 52, with the shank of the used tool facing the tool pot 521.

[0091] After step S63, the tool exchange operation control unit 72 moves the tool exchange arm 64 -Z (step S64). Figure 31(a) is a plan view showing the state after step S64 is completed, and Figure 31(b) is a right side view of Figure 31(a). As shown in Figures 31(a) and 31(b), as the tool exchange arm 64 moves -Z, the used tool held by the first tool gripping unit 642 is stored in the tool magazine 52 with its shank inserted into the tool pot 521 located furthest to the +Y side of the tool magazine 52.

[0092] Subsequently, the tool exchange operation control unit 72 moves the tool exchange arm 64 +Y (step S65). Figure 32(a) is a plan view showing the state after step S45 is completed, and Figure 32(b) is a right side view of the same figure (a). As shown in Figures 32(a) and 32(b), when the tool exchange arm 64 moves +Y, the grip of the used tool by the first tool gripping unit 642 is released, and the tool exchange arm 64 moves away from the tool magazine 52. Once step S65 is completed, the tool exchange operation according to the third operation pattern is finished. Steps S13 to S27, steps S31 to S45, and steps S51 to S65 described above correspond to an example of the tool exchange operation execution process.

[0093] According to the machine tool 1 of this embodiment described above, the tool exchange operation control unit 72 determines an operation pattern based on whether the currently installed tool T1 and the next tool to be installed T2 are long tools TL or standard tools TS, and by executing the tool exchange operation according to the determined operation pattern, the tool exchange operation can be performed without interference using a tool storage device 5 that can accommodate both long tools TL and standard tools TS. As a result, the machine tool 1 can be constructed at a low cost and made smaller.

[0094] Furthermore, since a second tool gripping section 643 is provided that moves within a range where the gripped tool does not interfere with the arm support section 63 even when the arm pivot axis 641 rotates repeatedly, regardless of whether it is a standard tool TS or a long tool TL, an operation pattern that avoids interference can be easily set. And, when one of the installed tool T1 and the next installed tool T2 is a long tool TL and the other of the installed tool T1 and the next installed tool T2 is a standard tool TS, the operation pattern is selected to grip the long tool TL with the second tool gripping section 643, which does not pose a risk of interference even when gripping and rotating the long tool TL, thus reliably avoiding interference between the long tool TL and the tool changer 6.

[0095] Next, a modified example of this embodiment will be described. In the following description, components with the same names as those described so far will be given the same reference numerals as those used so far, and redundant explanations may be omitted.

[0096] Figure 33 is a perspective view showing the tool storage device 5 of the first modified example. In Figure 33, the support column 51 and the magazine motor 53 are omitted from the illustration. Figure 34 is a perspective view showing the removal of the tool pot 521 from the tool magazine 52 shown in Figure 33.

[0097] As shown in Figure 34, the first modified tool storage device 5 differs from the tool magazine 52 of the previous embodiment in that multiple U-shaped notches are formed on the periphery of the annular portion of the magazine body 520 of the tool magazine 52, recessed from the outer edge toward the center. The tool pot 521 is placed in this notched portion and fixed to the magazine body 520 by screws. Therefore, by removing the screws, the tool pot 521 can be removed from the magazine body 520, exposing the notches. As shown in Figure 33, in this first modified tool storage device 5, by removing the tool pot 521 from the magazine body 520 in the second stage tool magazine 52, long tools TL can be stored in the first stage tool magazine 52. Note that the first stage tool magazine 52 may be the same tool magazine 52 as in the previous embodiment, which does not have notches.

[0098] Figure 35 is a cross-sectional view showing how a long tool TL is stored in the first-stage tool magazine 52 in a machine tool 1 equipped with the tool storage device 5 shown in Figure 33. In Figure 35, the first-stage tool magazine 52 is shown on the left side of the figure, and the second-stage tool magazine 52 is shown on the right side of the figure.

[0099] When storing the long tool TL in the tool storage device 5, the long tool TL is moved in the order shown in Figures 35(a), 35(b), and 35(c) and then stored in the tool storage device 5. Figure 35(a) shows that the long tool TL, held by the tool changing arm 64 (see Figure 2), is positioned slightly closer to the tool pot 521 in the first stage tool magazine 52 and separated in the +Y direction.

[0100] From this position, the tool changing arm 64 (see Figure 2) gripping the long tool TL moves -Y, so that, as shown in Figure 35(b), the long tool TL is positioned with a small gap in the Z-axis direction between it and the tool pot 521 located on the +Y side of the tool magazine 52, with the shank of the long tool TL facing the tool pot 521. At this time, the middle or tip (+Z direction) portion of the long tool TL fits into the U-shaped notch of the second stage magazine body 520, so the ring portion of the magazine body 520 and the long tool TL do not interfere with each other.

[0101] As the tool change arm 64 (see Figure 2) moves -Z from the position shown in Figure 35(b), the long tool TL is inserted into the tool pot 521 located on the +Y side of the tool magazine 52, as shown in Figure 35(c), and stored in the tool magazine 52. When removing the long tool TL from the first stage of the tool magazine 52, the long tool TL is moved in the order shown in Figures 35(c), 35(b), and 35(a).

[0102] In the machine tool 1 using the tool storage device 5 of the previous embodiment, even if the tool pot 521 of the second-stage tool magazine 52 is removed, the annular portion of the magazine body 520 of the second-stage tool magazine 52 interferes with the long tool TL, making it impossible to store the long tool TL in the first-stage tool magazine 52. In contrast, the machine tool 1 using the tool storage device 5 of this first modified example has the advantage of being able to further miniaturize the machine tool 1 by reducing the space required for the tool storage device 5 in the +Z direction by storing the long tool TL in the first-stage tool magazine 52, in addition to the advantages of the previous embodiment.

[0103] Figure 36 is a perspective view showing a second modified tool storage device 5. In Figure 36, the support column 51 and the magazine motor 53 are omitted from the illustration. Figure 37 is a right side view of the tool storage device 5 shown in Figure 36.

[0104] As shown in Figures 36 and 37, the tool magazine 52 of the second modified example differs from the tool magazine 52 of the previous embodiment in that it is provided with multiple grips 522 instead of multiple tool pots 521. That is, while the tool magazine 52 of the previous embodiment was a drum type provided with tool pots 521, the tool magazine 52 of the second modified example is a grip type provided with grips 522. Each grip 522 has a pair of radially projecting clamping pieces 5221 and a clamping spring 5222. The pair of clamping pieces 5221 are attached to the magazine body 520 so that their projecting ends are displaceable in directions that move toward and away from each other. The pair of clamping pieces 5221 are biased by the clamping spring 5222 in a direction that moves their projecting ends toward each other, and when no external force is applied, the projecting ends of the pair of clamping pieces 5221 are maintained at a predetermined distance apart. The grips 522 are arranged side by side with a circumferential (rotational) gap between adjacent grips 522.

[0105] Furthermore, the first-stage tool magazine 52 and the second-stage tool magazine 52 are connected at positions offset in the circumferential direction. As shown in Figure 37, this position is such that, when viewed from the second-stage tool magazine 52 to the first-stage tool magazine 52 (viewed in the Z-axis direction perpendicular to the plane of the paper in Figure 37), the grips 522 of the first-stage and the grips 522 of the second-stage tool magazine are arranged alternately in the circumferential direction. In other words, when viewed in the Z-axis direction, the tools held by the grips 522 of the first-stage tool magazine 52 are positioned between the grips 522 of the second-stage tool magazine 52 in an angular relationship, and the first-stage tool magazine 52 and the second-stage tool magazine 52 are connected in this manner.

[0106] Figure 38 is a cross-sectional view showing how a long tool is stored in the first-stage tool magazine in a machine tool 1 equipped with the tool storage device 5 shown in Figure 36. In Figure 38, the first-stage tool magazine 52 is shown on the left side of the figure, and the second-stage tool magazine 52 is shown on the right side of the figure.

[0107] When storing the long tool TL in the tool storage device 5, the long tool TL is moved in the order shown in Figure 38(a) and Figure 38(b) and then stored in the tool storage device 5. Figure 38(a) shows that the gripped portion of the long tool TL, which is held by the tool changing arm 64 (see Figure 2), is positioned opposite the grip 522 of the first stage tool magazine 52, separated in the Y-axis direction.

[0108] From this position, the tool changing arm 64 (see Figure 2) gripping the long tool TL moves -Y, causing the gripped portion of the long tool TL to contact the protruding end of the grip 522, pushing the protruding ends of the pair of gripping pieces 5221 apart against the biasing force of the gripping spring 5222, and the gripped portion of the long tool TL to enter between the pair of gripping pieces 5221. Then, as shown in Figure 38(b), the gripped portion of the long tool TL is gripped by the grip 522, and the long tool TL is stored in the tool storage device 5. At this time, the middle or tip portion of the long tool TL fits between the grips 522 of the second-stage tool magazine 52, so the second-stage tool magazine 52 and the long tool TL do not interfere with each other. When removing the long tool TL from the first-stage tool magazine 52, the long tool TL is moved in the order shown in Figures 38(b) and 38(a). Alternatively, the first-stage tool magazine 52 and the second-stage tool magazine 52 may be connected at the same angle without circumferential displacement. In that case, the spacing between the protruding ends of the pair of clamping pieces 5221 must be set so that the middle or tip portion of the long tool TL stored in the first-stage tool magazine 52 can enter between the pair of clamping pieces 5221 in the second-stage tool magazine 52.

[0109] In the machine tool 1 equipped with this second modified tool storage device 5, in addition to the effects of the first modified tool storage device 5, the machine tool 1 can be made even more compact because the space required for the tool storage device 5 in the +Z direction can be reduced.

[0110] The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the claims. For example, in this embodiment, an NC lathe equipped with a tool storage device 5 and a tool changing device 6 was described as an example of a machine tool 1, but the present invention may also be applied to other machine tools equipped with a tool storage device 5 and a tool changing device 6, such as a machining center. Furthermore, the machine tool 1 may be equipped with a guide bush that guides the tip portion of the workpiece W held by the spindle 2 so as to be slidable in the Z1 axis direction. In addition, a tool post to which a tool T such as a cutting tool is mounted may be provided separately from the tool spindle 4. Note that the opposing spindle 3 may be omitted. Moreover, in this embodiment, the Y axis direction, Y2 axis direction, Y3 axis direction, and Z axis direction, Z1 axis direction, Z2 axis direction, and Z3 axis direction were described as coinciding, but these may be in different directions.

[0111] Furthermore, even if a constituent element is included only in the description of each of the modified examples described above, that constituent element may be applied to other modified examples. [Explanation of Symbols]

[0112] 1 Machine tools 4 Tool spindle 5. Tool storage device 6 Tool changer 72 Exchange Operation Control Unit 642 1st tool grip part 643 2nd tool grip part T1 Installation Tool T2 Next installation tool TL long tool TS normal tool

Claims

1. A tool spindle on which a long tool of a predetermined length or longer and a standard tool shorter than the predetermined length are interchangeably mounted, A tool storage device capable of storing both the long tool and the standard tool, A tool changing device having a first tool gripping section and a second tool gripping section, for exchanging the long tool or the standard tool stored in the tool storage device with the mounted tool attached to the tool spindle, A machine tool comprising a tool change operation control unit that determines an operation pattern in a tool change operation using the tool change device, based on whether the mounting tool is the long tool or the standard tool, and whether the next tool to be mounted on the tool spindle is the long tool or the standard tool.

2. The tool changing device has an arm pivot axis that rotates repeatedly within a predetermined angular range, The first tool gripping portion is formed to protrude radially from the arm pivot axis, and while gripping a standard tool and the arm pivot axis rotates repeatedly, the gripped standard tool does not interfere with the tool changing device. However, while gripping a long tool and the arm pivot axis rotates repeatedly, the gripped long tool moves within a range that causes it to interfere with the tool changing device. The machine tool according to claim 1, characterized in that the second tool gripping portion is formed to protrude radially from the arm pivot axis at a circumferential distance from the first tool gripping portion, and moves within a range in which the gripped standard tool and the long tool do not interfere with the tool changing device even when the arm pivot axis rotates repeatedly while gripping either the standard tool or the long tool.

3. The machine tool according to claim 2, characterized in that the replacement operation control unit controls the gripping of the ordinary tool with the first tool gripping unit and the long tool with the second tool gripping unit when one of the mounting tool and the next mounting tool is the long tool and the other of the mounting tool and the next mounting tool is the ordinary tool.

4. The machine tool according to any one of claims 1 to 3, characterized in that, when both the next tool to be mounted and the mounted tool are the long tool, the second tool gripping unit grips the mounted tool and removes it from the tool spindle, and before storing the removed mounted tool in the tool storage device, the first tool gripping unit grips the next tool to be mounted and removes it from the tool storage device and mounts the next tool to be mounted on the tool spindle.

5. A control method for a machine tool comprising: a tool spindle on which a long tool of a predetermined length or longer and a standard tool shorter than the predetermined length are interchangeably mounted; a tool storage device capable of accommodating both the long tool and the standard tool; and a tool changing device for exchanging the long tool or standard tool stored in the tool storage device with a mounted tool attached to the tool spindle, An information acquisition step to acquire information on whether the mounting tool is the long tool or the standard tool, and information on whether the next mounting tool to be mounted on the tool spindle is the long tool or the standard tool, A method for controlling a machine tool, characterized by comprising: a replacement operation determination step, which determines an operation pattern for a tool replacement operation using the tool replacement device based on the information acquired in the information acquisition step.

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