Control devices, machine tools, control methods, and computer programs

Abstract

The present invention provides a control device that can suppress collisions between tools when transporting tools between multiple tool magazines, without requiring a detection unit in the storage compartment. [Solution] When the control device executes a command to move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, it executes a first process in the first magazine to locate the designated first storage unit at the first replacement position, after the first process is executed, it executes a second process in the tool transport device to transport the gripping unit to the first replacement position, after the second process is executed, it executes a detection process in the detection unit to detect the presence or absence of a tool in the first storage unit located at the first replacement position, and if the detection process detects the absence of a tool, it executes a third process in the tool transport device to transport the gripping unit from the first replacement position to a non-interference position.

Description

Technical Field

[0001] The present technology relates to a control device, a machine tool, a control method, and a computer program.

Background Art

[0002] Machine tools have been proposed that can exchange tools between multiple tool magazines. The machine tool includes a plurality of tool magazines and switches provided in the tool holding parts of the plurality of tool magazines respectively for detecting the presence or absence of tools. The machine tool checks the presence or absence of tools in each tool holding part based on the detection results of the switches. When exchanging tools, if the presence or absence state of the tool in the tool holding part is not normal, warnings or abnormal stops are performed (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] If tool replacement is performed when the presence or absence state of the tool in the tool holding part is not normal, there is a risk of tool collision. However, providing switches in each of the plurality of tool holding parts to detect the presence or absence state of the tool increases the manufacturing cost.

[0005] In view of such circumstances, the present disclosure provides a control device, a machine tool, a control method, and a computer program that can reduce manufacturing costs compared to the case of providing them in each first storage part and each second storage part, can avoid tool collision, and can transfer tools between a plurality of tool magazines.

Means for Solving the Problems

[0006] A control device according to one embodiment of the present disclosure controls a first magazine having a plurality of first storage compartments for storing tools, a second magazine having a plurality of second storage compartments for storing tools, a tool transport device capable of transporting a gripping part for gripping a tool to a first replacement position for removing or storing a tool in the first magazine, a second replacement position for removing or storing a tool in the second magazine, and a non-interference position different from the first and second replacement positions and non-interfering with the first and second magazines, and a detection unit provided in the tool transport device for detecting the presence or absence of a tool based on the gripping state of the gripping part, wherein the first When a command is executed to move a tool from one of the magazine and the second magazine to the other of the first magazine and the second magazine, the first magazine performs a first process to locate the designated first storage unit at the first replacement position, and after the first process, the tool transport device performs a second process to transport the gripping unit to the first replacement position, and after the second process, the detection unit performs a detection process to detect the presence or absence of a tool in the first storage unit located at the first replacement position, and if the detection process detects the absence of a tool, the tool transport device performs a third process to transport the gripping unit from the first replacement position to the non-interference position.

[0007] In this disclosure, a detection unit for detecting the presence or absence of a tool is provided in the tool transport device, and tools are transported between the first magazine and the second magazine. Furthermore, if the absence of a tool is detected in the first storage unit located at the first replacement position, the control device transports the gripping unit to a non-interference position.

[0008] In one embodiment of the present disclosure, the control device includes a tool movement process in which the first to third processes move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, and the tool movement process is repeatedly executed, and in the first tool movement process, a tool absence flag is set in association with the first storage unit where the detection unit has detected the absence of a tool, and when the second tool movement process is executed after the first tool movement process, after the execution of the first process, it is determined whether the tool absence flag is set for the first storage unit located at the first replacement position, and if it is determined that the tool absence flag is set for the first storage unit located at the first replacement position, the second process and the detection process are omitted.

[0009] In this disclosure, if it is determined that the toolless flag is set for the first storage unit that was assigned to the first replacement position in the previous tool movement process, the second process and the detection process are omitted in the current tool movement process.

[0010] In one embodiment of the present disclosure, when the presence of a tool is detected in the detection process, the tool transport device performs a transport operation of the gripping part from the first replacement position to the second replacement position, and then performs a transport operation of the gripping part from the second replacement position to the non-interference position.

[0011] In this disclosure, if a tool is located in the first storage compartment at the first replacement position, the gripping portion is transported from the first replacement position to the second replacement position, and then the gripping portion is transported from the second replacement position to the non-interference position.

[0012] In one embodiment of the present disclosure, the control device includes a tool movement process in which the first to fourth processes move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, and repeatedly executes the tool movement process. In the first tool movement process, a removed flag is set in association with the first storage unit where the presence of a tool has been detected by the detection unit, indicating that the tool has been removed by the transport operation of the gripping unit from the first replacement position to the second replacement position by the tool transport device. When a second tool movement command is executed after the first tool movement process, after the execution of the first process, it is determined whether the removed flag has been set for the first storage unit located at the first replacement position. If it is determined that the removed flag has been set for the first storage unit located at the first replacement position, the second process and the detection process are omitted.

[0013] In this disclosure, if it is determined that the first storage unit, which was assigned to the first replacement position in the previous tool movement process, has a removed flag set, the second process and the detection process are omitted in the current tool movement process.

[0014] A control device according to one embodiment of the present disclosure includes a storage unit that stores information indicating whether a tool is stored or not in each first storage unit, and if the presence or absence of the tool detected in the detection process does not correspond to whether the tool is stored or not as indicated by the information for the first storage unit located at the first replacement position, an abnormality process is executed.

[0015] In this disclosure, if the presence or absence of a tool detected by the detection process does not correspond to whether the tool is stored or not, as indicated by the information stored in the memory unit, an abnormality process is executed for the first storage unit located at the first replacement position.

[0016] In one embodiment of the present disclosure, the control device includes, in the tool movement process, a fifth process and a sixth process which are performed before the execution of the first process or after the execution of the third process, wherein the fifth process is a process in which the second magazine places the designated second storage unit at the second replacement position, and the sixth process is a process in which, after the execution of the fifth process, the tool transport device performs a transport operation of the gripping unit from the second replacement position to the first replacement position, and after the execution of the fifth process and before the execution of the sixth process, the detection unit performs a second detection process to detect the presence or absence of a tool in the second storage unit located at the second replacement position, and if the presence or absence of a tool is detected in the second detection process, after the execution of the sixth process, the setting of the no-tool flag for the first storage unit located at the first replacement position is released.

[0017] In this disclosure, in the fifth process, the designated second storage unit is located at the second replacement position, and in the sixth process, the gripping unit is transported from the second replacement position to the first replacement position. After the execution of the fifth process and before the execution of the sixth process, the presence or absence of a tool in the second storage unit located at the second replacement position is detected, and if the presence or absence of a tool is detected, after the execution of the sixth process, the flag indicating no tool is set for the first storage unit located at the first replacement position is removed.

[0018] A control device according to one embodiment of the present disclosure determines whether or not it is possible to manually attach a tool to the first storage compartment, and if it determines that it is possible to manually attach a tool to the first storage compartment, it releases the "no tool" flag set in the first storage compartment.

[0019] In this disclosure, if it is possible to manually attach a tool to the first storage compartment, the tool-less flag set for the first storage compartment is released.

[0020] A control device according to one embodiment of the present disclosure determines whether or not it is possible to manually attach a tool to the first storage compartment, and if it is determined that it is possible to manually attach a tool to the first storage compartment, it removes the removed flag set on the first storage compartment.

[0021] In this disclosure, if it is possible to manually attach a tool to the first storage compartment, the removed flag set on the first storage compartment is released.

[0022] A machine tool according to one embodiment of the present disclosure includes: a first magazine having a plurality of first storage compartments for storing tools; a second magazine having a plurality of second storage compartments for storing tools; a tool transport device capable of transporting a gripping part for gripping a tool to a first replacement position for removing or storing a tool in the first magazine, a second replacement position for removing or storing a tool in the second magazine, and a non-interference position different from the first and second replacement positions and non-interfering with the first and second magazines; a detection unit provided in the tool transport device for detecting the presence or absence of a tool based on the gripping state of the gripping part; and a control device for controlling the first magazine, the second magazine, the tool transport device, and the detection unit. A machine tool comprising the above, wherein when the control device executes a command to move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, it executes a first process in the first magazine to locate the designated first storage unit at the first replacement position, after the first process is executed, it executes a second process in the tool transport device to transport the gripping unit to the first replacement position, after the second process is executed, it executes a detection process in the detection unit to detect the presence or absence of a tool in the first storage unit located at the first replacement position, and if the detection process detects the absence of a tool, it executes a third process in the tool transport device to transport the gripping unit from the first replacement position to the non-interference position.

[0023] In this disclosure, a detection unit for detecting the presence or absence of a tool is provided in the tool transport device, and tools are transported between the first magazine and the second magazine. Furthermore, if the absence of a tool is detected in the first storage unit located at the first replacement position, the control device transports the gripping unit to a non-interference position.

[0024] The machine tool according to an embodiment of the present disclosure includes a regulation cover that regulates attaching a tool to the second magazine without using the tool transfer device.

[0025] In the present disclosure, an operator cannot attach or detach a tool to / from the second magazine. Transfer of a tool between the first magazine and the second magazine is possible only by a tool transfer device.

[0026] A control method according to an embodiment of the present disclosure is a control method for controlling a tool transfer device capable of transferring a gripping portion that grips a tool to a non-interference position that is different from a first replacement position for removing or storing a tool in a first magazine having a plurality of first storage portions in which tools are stored, a second magazine having a plurality of second storage portions in which tools are stored, a second replacement position for removing or storing a tool in the second magazine, and that does not interfere with the first magazine and the second magazine, and a detection unit provided in the tool transfer device for detecting the presence or absence of a tool based on the gripping state of the gripping portion. When executing a command to move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, a first process of identifying a designated first storage portion to the first replacement position is executed in the first magazine. After execution of the first process, a second process of performing a transfer operation of the gripping portion to the first replacement position is executed by the tool transfer device. After execution of the second process, a detection process of detecting the presence or absence of a tool in the first storage portion disposed at the first replacement position is executed by the detection unit. When the absence of a tool is detected in the detection process, a third process of performing a transfer operation of the gripping portion from the first replacement position to the non-interference position is executed by the tool transfer device.

[0027] In the present disclosure, a detection unit for detecting the presence or absence of a tool is provided in the tool transfer device to transfer the tool between the first magazine and the second magazine. Further, when the absence of a tool is detected in the first storage portion disposed at the first replacement position, the control device transfers the gripping portion to the non-interference position.

[0028] A computer program according to one embodiment of the present disclosure is a computer program executable by a control device that controls a first magazine having a plurality of first storage compartments for storing tools, a second magazine having a plurality of second storage compartments for storing tools, a tool transport device capable of transporting a gripping part for gripping a tool to a first replacement position for removing or storing a tool in the first magazine, a second replacement position for removing or storing a tool in the second magazine, and a non-interference position different from the first and second replacement positions and which does not interfere with the first and second magazines, and a detection unit provided in the tool transport device for detecting the presence or absence of a tool based on the gripping state of the gripping part. In this configuration, when the control device is given a command to move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, the first magazine performs a first process to locate the designated first storage unit at the first replacement position, the tool transport device performs a second process to transport the gripping unit to the first replacement position after the first process has been performed, the detection unit performs a detection process to detect the presence or absence of a tool in the first storage unit located at the first replacement position, and if the detection process detects the absence of a tool, the tool transport device performs a third process to transport the gripping unit from the first replacement position to the non-interference position.

[0029] In this disclosure, a detection unit for detecting the presence or absence of a tool is provided in the tool transport device, and tools are transported between the first magazine and the second magazine. Furthermore, if the absence of a tool is detected in the first storage unit located at the first replacement position, the control device transports the gripping unit to a non-interference position. [Effects of the Invention]

[0030] In a control device, machine tool, control method, and computer program according to one embodiment of this disclosure, manufacturing costs can be reduced by providing the detection unit in the tool transport device, compared to providing it in each of the first and second storage units. Furthermore, tools can be transported between multiple tool magazines while avoiding collisions between tools. [Brief explanation of the drawing]

[0031] [Figure 1] This is a schematic perspective view of a machine tool according to Embodiment 1. [Figure 2] This is a schematic left side view of a machine tool. [Figure 3] This is a schematic plan view of a machine tool. [Figure 4] This is a schematic perspective view of a machine tool. [Figure 5] This is a magnified view showing the structure near the cover. [Figure 6] Figure 3 shows a cross-sectional view with the line VI-VI as the cutting line. [Figure 7] This is a schematic front view of the pod in a non-gripping state. [Figure 8] Figure 7 is a schematic cross-sectional view with line VIII-VIII as the cutting line. [Figure 9] This is a schematic cross-sectional view of pod 9f in a gripping state. [Figure 10] This is a schematic cross-sectional view of pod 9f in an air-sounding state. [Figure 11] This is an explanatory diagram illustrating the relationship between the piston position and the detection ranges of the first and second detection units. [Figure 12] This table shows the relationship between the piston's position range, the detection results from the first and second detection units, and the hand's state. [Figure 13] This is a partially enlarged view showing the tool transport path between the replacement position arm for the first magazine and the replacement position arm for the second magazine. [Figure 14] This is a block diagram showing the control device, motor, first detection unit, second detection unit, solenoid valve, notification unit, and operation unit. [Figure 15]This is a flowchart illustrating the tool transport process performed by the control unit. [Figure 16] This is a flowchart illustrating the tool transport process performed by the control unit. [Figure 17] This is a flowchart illustrating the tool transport process performed by the control unit. [Figure 18] This flowchart explains the monitoring process for determining whether a tool can be attached to the first magazine. [Modes for carrying out the invention]

[0032] The present invention will be described below based on drawings showing machine tools according to embodiments. In the following description, the directions up, down, front, back, left, and right in the figures will be used. Up, down, front, back, left, and right are merely directional notations used for ease of understanding, and the directional notations are not limited to these.

[0033] A machine tool will be described using Figures 1 to 6. The machine tool comprises a base 1, a workpiece holder 2, an XY movement mechanism 3, a vertical column 4, a Z movement mechanism 5, a first magazine 6, two second magazines 7 and 8, a spindle head 10, etc. The base 1 has a rectangular shape in plan view and extends in the front-to-back direction. An XY movement mechanism 3, which can move in the left-to-right direction (X direction) and the front-to-back direction (Y direction), is provided on the upper front side of the base 1. The workpiece holder 2 is provided above the XY movement mechanism 3. The workpiece holder 2 moves in the X and Y directions by the XY movement mechanism 3. The workpiece holder 2 holds the workpiece.

[0034] A vertical column 4 is provided on the upper rear side of the base 1 via a height adjustment section 4a. The vertical column 4 is a rectangular parallelepiped with a front, rear, and left and right sides. A control device 60 is provided on the rear side of the vertical column 4. The control device 60 controls the drive of the machine tool. A Z-axis movement mechanism 5, which is movable in the vertical direction (Z direction), is provided on the front of the vertical column 4. A spindle head 10 is provided on the Z-axis movement mechanism 5. The spindle head 10 has a spindle 10a that extends vertically. A tool is attached to the lower end of the spindle 10a.

[0035] A first magazine 6 for storing multiple tools is provided on the front side of the spindle head 10. The first magazine 6 is connected to the vertical column 4 via two first support parts 20 and 25. One first support part 20 protrudes forward from the front left side of the vertical column 4. The other first support part 25 protrudes forward from the front right side of the vertical column 4. The first magazine 6 is connected to the protruding ends of each first support part 20 and 25. The first magazine 6 comprises a disc 6a, arms 6b, and a cover 6d. A motor 6f (see Figure 5) is connected to the disc 6a, and the disc 6a rotates around its central axis by the drive of the motor 6f. Multiple arms 6b are provided radially on the periphery of the disc 6a. Each arm 6b has a bifurcated shape and holds a tool. That is, each arm 6b stores a tool. The cover 6d covers the outside of each arm 6b. The cover 6d is rotatable and rotates with the arm 6b during tool changes with the spindle, without interfering with tool changes. Each arm 6b is not equipped with a detection unit to detect the presence or absence of a tool. The arm 6b constitutes the first storage section.

[0036] The first magazine 6 is positioned such that the central axis of the disc 6a extends approximately in the front-to-back direction and the disc 6a is tilted forward. The lower end of the first magazine 6 is the tool change position. When a tool is to be mounted on the spindle, the arm 6b gripping the tool is positioned at the tool change position and the Z-movement mechanism 5 is moved downward. Based on the downward movement of the Z-movement mechanism 5, the spindle 10a mounts the tool gripped by the arm 6b. When a tool is to be removed from the spindle 10a, an empty arm 6b is positioned at the tool change position and the Z-movement mechanism 5 is moved upward. Based on the upward movement of the Z-movement mechanism 5, the arm 6b grips the tool on the spindle 10a and the tool is removed from the spindle 10a.

[0037] The tool mounted on the spindle 10a processes the workpiece held in the workpiece holder 2. The XY movement mechanism 3 adjusts the front-to-back, left-to-right position of the workpiece relative to the tool (spindle), and the Z movement mechanism 5 adjusts the vertical position of the tool.

[0038] The second magazine 7 is located to the right of the upright column 4, and the second magazine 8 is located to the left. The second support section 30 connects the rear end of the left first support section 20, i.e., the connection point between the first support section 20 and the upright column 4, to the second magazine 8. The second support section 30 supports the second magazine 8. The second support section 31 connects the rear end of the right first support section 25, i.e., the connection point between the first support section 25 and the upright column 4, to the second magazine 7. The second support section 31 supports the second magazine 7.

[0039] The second magazine 8 comprises a disc-shaped wheel 8a, a plurality of arms 8b, and a motor 8c. The motor 8c is fixed to the second support portion 30. The radial center of the wheel 8a protrudes in the axial direction. With the radial center as the apex, the wheel 8a is generally frustoconical in shape. A plurality of arms 8b are provided on the outer circumference of the wheel 8a. The plurality of arms 8b are arranged in the circumferential direction of the wheel 8a. Each arm 8b has a bifurcated shape and is capable of holding a tool. That is, each arm 8b stores a tool. In two adjacent arms 8b, a portion of each arm 8b overlaps in the circumferential direction of the wheel 8a. Alternatively, a plurality of arms 8b may be provided radially on the outer circumference of the wheel 8a so that two adjacent arms 8b do not overlap. The second magazine 8 stores multiple tools using the plurality of arms 8b. The radial center on the recessed side of the wheel 8a is connected to the motor 8c and a reduction gear (not shown). The rotation of the motor 8c causes the wheel 8a and arm 8b to rotate in the circumferential direction. Arm 8b constitutes the second storage section. No detection unit for detecting the presence or absence of a tool is provided on each arm 8b.

[0040] As shown in Figure 4, the machine tool is equipped with a machining chamber 40. Inside the machining chamber 40 are a workpiece holder 2, an XY movement mechanism 3, a vertical column 4, a Z movement mechanism 5, a first magazine 6, two second magazines 7 and 8, a spindle head 10, etc. The machining chamber 40 is mounted on a base 1 and is equipped with a front wall 41, a right wall 42, a left wall, a ceiling 46, and a rear wall. A rectangular opening is formed in the center of the front wall 41, and an opening / closing door 41a is provided in the opening. An operation panel 41b is provided to the right of the opening / closing door 41a on the front wall 41. The operation panel 41b includes a touch panel, keyboard, switches, mouse, etc., for receiving information input from the operator. An opening / closing detector 41c is provided on the opening / closing door 41a. The opening / closing detector 41c detects the opening and closing of the opening / closing door 41a.

[0041] As shown in Figure 5, the second magazine 8 is covered by a cover 52. The cover 52 has a front, rear, left, and bottom surface. The front, rear, left, and bottom surfaces of the cover 52 cover the front, rear, left, and bottom sides of the second magazine 8. An opening 52a is formed on the front surface of the cover 52. The opening 52a is opened and closed by a shutter (not shown). The shutter is provided with a drive source (not shown), such as an air cylinder and a solenoid valve. The control unit 60a controls the solenoid valve to open and close the shutter. Note that in Figure 5, the left side is omitted so that the second magazine 8 can be seen.

[0042] When a tool is transported between the first magazine 6 and the second magazine 8, the tool passes through the opening 52a. The operator has difficulty approaching the arm 8b due to the cover 52. The operator cannot attach or detach the tool to or from the arm 8b.

[0043] Although the right side of the second magazine 8 is not covered by the cover 52, the presence of the support column 4 makes it difficult for the operator to approach the arm 8b, and therefore impossible to attach or detach tools to the arm 8b. Similarly, although the upper side of the second magazine 8 is not covered by the cover 52, its high position makes it difficult for the operator to approach the arm 8b, and therefore impossible to attach or detach tools to the arm 8b. In other words, the cover 52 restricts the attachment and detachment of tools to the second magazine 8 without using the tool transport device 9. The second magazine 7 is covered by a cover of a similar configuration (not shown).

[0044] As shown in Figure 6, the arm 6b of the first magazine 6 is closest to the arm 8b of the second magazine 8 at the first replacement position P1, and the arm 8b of the second magazine 8 is closest to the arm 6b of the first magazine 6 at the second replacement position P2. That is, the shortest distance between each arm 6b of the first magazine 6 and each arm 8b of the second magazine 8 is between the arm 6b at the first replacement position P1 and the arm 8b at the second replacement position P2. Therefore, the tool 50 is transported between the first replacement position P1 and the second replacement position P2.

[0045] Hereinafter, the arm 6b of the first magazine 6 positioned at the first replacement position P1 will be referred to as the replacement position arm 6c, and the arm 8b of the second magazine 8 positioned at the second replacement position P2 will be referred to as the replacement position arm 8d. The tool transport device 9 performs tool changes between the replacement position arm 6c and the replacement position arm 8d.

[0046] A tool transport device 9 is positioned inside the wheel 8a. The tool transport device 9 transports tools. The tool transport device 9 comprises a motor 9a, a ball screw 9b, a nut 9c, a track 9d, a slider 9e, a pod 9f, and a connecting part 9g. The pod 9f constitutes a holding part. The second support part 30 supports the ball screw 9b and the track 9d. The ball screw 9b is connected to the rotating shaft of the motor 9a. The nut 9c is connected to the ball screw 9b.

[0047] As shown in Figure 6, the track 9d is positioned next to the ball screw 9b. The track 9d is fixed in a position away from the central axis 81a of the wheel 8a. The track 9d extends along the long side of the replacement position arm 8d. One end of the track 9d faces the replacement position arm 8d. The slider 9e is slidably mounted on the track 9d. The pod 9f is attached to the slider 9e. The connecting part 9g connects the slider 9e and the nut 9c. The motor 9a drives the ball screw 9b, causing the nut 9c to move along the ball screw 9b, and the slider 9e, connecting part 9g, and pod 9f to move along the track 9d. The pod 9f constitutes the gripping part.

[0048] Pod 9f grips the tool. Pod 9f moves between a first gripping position K1 and a second gripping position K2. The first gripping position K1 is the position where Pod 9f grasps the tool 50 gripped by the replacement position arm 6c, and corresponds to the first replacement position P1. The second gripping position K2 is the position where Pod 9f grasps the tool 50 gripped by the replacement position arm 8d, and corresponds to the second replacement position P2.

[0049] The tool transfer device 9 transfers tools between the arm 6b of the first magazine 6 and the arm 8b of the second magazine 8. In other words, the second magazine 8 is configured to allow tool exchange with the first magazine 6. By providing the second magazine 8, the number and types of usable tools can be increased compared to the case where only the first magazine 6 is provided.

[0050] The second magazine 7 is positioned symmetrically with the second magazine 8, and its configuration is the same as that of the second magazine 8, so a detailed explanation will be omitted. A tool transport device (not shown) is also provided inside the second magazine 7, and the tool transport device transfers tools between the arm 6b of the first magazine 6 and the arm 8b of the second magazine 7.

[0051] Figure 7 is a schematic front view of the pod 9f in a non-gripping state, and Figure 8 is a schematic cross-sectional view taken along the line VIII-VIII in Figure 7. As shown in Figure 7, the pod 9f comprises a cylinder 90, a piston 91, a rod 92, a support plate 93, two pivots 94, two arms 95, two hands 96, and a connecting shaft 97.

[0052] The cylinder 90 comprises a cylindrical portion extending in the front-rear direction, a front portion provided at the front end of the cylindrical portion, and a rear portion provided at the rear end of the cylindrical portion. A support plate 93 is provided on the front portion of the cylinder 90. A chamber 90c is provided inside the cylinder 90. A piston 91 is housed in the chamber 90c. The piston 91 is movable in the axial direction of the cylinder 90. A rod 92 protrudes forward from the piston 91, passes through the front portion of the cylinder 90 and the support plate 93, and protrudes from the support plate. The rod 92 moves back and forth with the back-and-forth movement of the piston 91. The piston 91 corresponds to the movable part.

[0053] Two protrusions 93a project forward from the support plate 93. The two protrusions 93a are separated vertically, and in the vertical direction, the rod 92 is located between the two protrusions 93a. The protrusions 93a extend horizontally. A pivot 94 extending vertically is provided between the left end of the upper protrusion 93a and the left end of the lower protrusion 93a. A pivot 94 extending vertically is provided between the right end of the upper protrusion 93a and the right end of the lower protrusion 93a.

[0054] Arms 95 are connected to the left and right pivots 94. As shown in Figure 8, the arm 95 has an L-shape in plan view, with the first side 95a and the second side 95b connected at approximately a right angle. The corners 95c of the arm 95 are connected to the pivots 94.

[0055] The first side 95a of the left arm 95 protrudes to the right from the corner 95c of the arm 95, and the second side 95b of the left arm 95 protrudes forward from the corner 95c of the arm 95. The first side 95a of the right arm 95 protrudes to the left from the corner 95c of the arm 95, and the second side 95b of the right arm 95 protrudes forward from the corner 95c of the arm 95.

[0056] The first side portion 95a of the left arm 95 and the first side portion 95a of the right arm 95 are connected to the rod 92 by a connecting shaft 97. The first side portion 95a of the left arm 95 and the first side portion 95a of the right arm 95 are rotatable around the axis of the connecting shaft 97.

[0057] A hand 96 is provided on the right side of the second side 95b of the left arm 95. A hand 96 is provided on the left side of the second side 95b of the right arm 95. The hand 96 corresponds to the gripping part.

[0058] The hand 96 is columnar in shape, extending vertically. A curved surface is formed on the right side of the left hand 96, projecting to the left in a plan view. A curved surface is formed on the left side of the right hand 96, projecting to the right in a plan view. The curvature of the curved surfaces corresponds to the curvature of the circumferential surface of the tool 50.

[0059] When the solenoid valve 63 (see Figure 14) is switched to the second position, compressed air is supplied from the second port 90b to the rear side of the chamber 90c, and the air from the front side of the chamber 90c is discharged from the first port 90a. As shown in Figure 8, the piston 91 is positioned at the front end of the chamber 90c, and the rod 92 moves forward. The two second sides 95b are inclined with respect to the rod 92 such that the distance between the two second sides 95b in the left-right direction increases as it moves towards the front. That is, the two hands 96 are positioned far apart from each other and are in a non-gripping state, not gripping the tool 50.

[0060] Figure 9 is a schematic cross-sectional view of the pod 9f in the gripping state. When the solenoid valve 63 (see Figure 14) is switched to the first position, air from the rear of the chamber 90c is discharged from the second port 90b, and compressed air is supplied to the front of the chamber 90c from the first port 90a. As shown in Figure 9, the piston 91 is located in the center of the chamber 90c in the front-rear direction, and the rod 92 moves further rearward than in the state shown in Figure 8. The two second sides 95b become approximately parallel to each other. That is, the two hands 96 are closer to each other than in the state shown in Figure 8, and are in a gripping state that grips the tool 50. Note that the posture and position of the piston 91, rod 92, arm 95 and hand 96 in Figure 9 are the posture and position when the two hands 96 are gripping the tool 50, i.e., when the tool 50 is preventing the hands 96 from approaching each other.

[0061] Figure 10 is a schematic cross-sectional view of the pod 9f in an idle state. The idle state is, for example, the state when the hand 96 performs the action of gripping the tool 50 against empty arms 6b and 8b. As shown in Figure 10, the piston 91 is located at the rear end of the chamber 90c, and the rod 92 moves to the rear. The two second sides 95b are inclined with respect to the rod 92 such that the distance between the two second sides 95b in the left-right direction decreases as it moves towards the front. That is, the two hands 96 are in a position that is excessively close to each other, resulting in an idle state. In the idle state, the tool 50 does not prevent the hands 96 from approaching each other, so the two hands 96 are excessively close to each other.

[0062] As shown in Figure 7, a first detection unit 61 and a second detection unit 62 are mounted on the right side of the cylinder 90. The first detection unit 61 is located at the rear of the cylinder 90, and the second detection unit 62 is located at the front of the cylinder 90. In other words, the first detection unit 61 and the second detection unit 62 are separated front to back.

[0063] The piston 91 is equipped with a magnet. The first detection unit 61 and the second detection unit 62 are equipped with magnetic sensors. The first detection unit 61 detects whether the piston 91 is located in the center of the chamber 90c in the front-rear direction, that is, whether the hand 96 is in a gripping state. The second detection unit 62 detects whether the piston 91 is located at the front end of the chamber 90c, that is, whether the hand 96 is not in a gripping state. Note that the magnetic sensor is an example of a proximity sensor. An optical sensor, ultrasonic sensor, or contact-type sensor may be used instead of the magnetic sensor.

[0064] Figure 11 is an explanatory diagram illustrating the relationship between the position of the piston 91 and the detection ranges of the first detection unit 61 and the second detection unit 62. In Figure 11, Pa indicates the position of the piston 91 where the two hands 96 are at their maximum distance from each other. The state in which the hands 96 are at their maximum distance from each other is included in the non-gripping state. The position of the piston 91 and the orientation of the hands 96 at position Pa are, for example, the positions and orientations shown in Figure 8.

[0065] Pb indicates the gripping reference position of the piston 91 when the hand 96 grips the tool 50 with no chips between the tool 50 and the hand 96. The state in which the hand 96 grips the tool 50 with no chips is included in the gripping state. The position of the piston 91 and the orientation of the hand 96 at position Pb are, for example, the positions and orientations shown in Figure 9.

[0066] Pc indicates the position of the piston 91 where the two hands 96 are closest together. This closest position of the two hands 96 is included in the air-running state. The position of the piston 91 and the orientation of the hands 96 at position Pc are, for example, those shown in Figure 10.

[0067] The distance between position Pa and position Pc is the stroke width of the piston 91 in cylinder 90. Within the stroke width, position Pa is located at the foremost position, and position Pc is located at the rearmost position.

[0068] D1 is the maximum width in the first detection unit 61 that can detect the piston 91. The maximum width D1 comprises a main detection width d1 that is not affected by environmental factors, such as temperature, and a secondary detection width k1 that is affected by environmental factors. The secondary detection width k1 is located at both ends of the maximum width D1. The secondary detection width k1 is a width that changes, for example, due to temperature changes. As the temperature decreases, the secondary detection width k1 becomes longer, and as the temperature increases, the secondary detection width k1 becomes shorter. The maximum width D1 corresponds to the first detection range.

[0069] Pd is the foremost position of the maximum width D1, and lies between position Pa and position Pb. The front end position of the main detection width d1 is located behind position Pd by the sub-detection width k1. The rearmost position of the maximum width D1 is Pe. The rear end position of the main detection width d1 is position Pb. That is, the width between position Pb and position Pe is the sub-detection width k1.

[0070] D2 is the maximum width in the second detection unit 62 that can detect the piston 91. The maximum width D2 comprises a main detection width d2 that is not affected by environmental factors, such as temperature, and two sub-detection widths k2 that are affected by environmental factors. The sub-detection widths k2 are located at both ends of the maximum width D2. The main detection width d1 and the main detection width d2 are approximately the same distance apart. The sub-detection width k2 and the sub-detection width k1 are approximately the same distance apart. The relationship between the sub-detection width k2 and temperature is the same as that of the sub-detection width k1. The maximum width D2 corresponds to the second detection width.

[0071] Pf is the foremost position of the maximum width D2, and is in front of position Pa. Pg is the rearmost position of the maximum width D2, and is between positions Pd and Pb. The distance between positions Pd and Pg is longer than the sub-detection widths k1 and k2. Between positions Pd and Pg, the front end portion of the maximum width D1 and the rear end portion of the maximum width D2 overlap, resulting in a rear sub-detection width k2 and a front sub-detection width k1. Ph is the rear end position of the main detection width d2, and is between positions Pd and Pg.

[0072] Position Pa is located approximately in the center of the maximum width D2. Since the piston 91 does not move in front of position Pa, the portion of the maximum width D2 in front of position Pa is not used for detecting the piston 91.

[0073] If the piston 91 is located between position Pa and position Pg, the second detection unit 62 detects the piston 91. If the piston 91 is located between position Pd and position Pe, the first detection unit 61 detects the piston 91.

[0074] If the piston 91 is located between position Pa and position Pd, i.e., within range R1, the second detection unit 62 detects the piston 91, while the first detection unit 61 does not. When the piston 91 is within range R1, the hand 96 is in a non-gripping state. Range R1 corresponds to the second range.

[0075] If the piston 91 is between position Pe and position Pg, i.e., within range R3, the first detection unit 61 detects the piston 91, while the second detection unit 62 does not detect the piston 91. When the piston 91 is within range R3, the hand 96 is in a gripping state. Range R3 corresponds to the first range.

[0076] As mentioned above, position Pb is the gripping reference position of the piston 91 in which the hand 96 grips the tool 50 when there are no chips. Even if the two hands 96 are slightly closer than the gripping reference position Pb, it is still acceptable to determine that the hand 96 is in a gripping state. Even if chips are caught between the hand 96 and the tool 50, the hand 96 can still grip the tool 50, so it is still acceptable to determine that the hand 96 is in a gripping state. Therefore, if the piston 91 is in the range R3 between position Pe, which is behind the gripping reference position Pb, and position Pg, which is in front of the gripping reference position Pb, it can be determined that the hand 96 is in a gripping state.

[0077] If the piston 91 is located between position Pe and position Pc, i.e., within range R4, the first detection unit 61 and the second detection unit 62 do not detect the piston 91. If the piston 91 is within range R4, the hand 96 is in an idle state.

[0078] When the piston 91 is between position Pd and position Pg, i.e., within range R2, the first detection unit 61 and the second detection unit 62 detect the piston 91. When the piston 91 is within range R2, the hand 96 is in a state that is neither gripping, non-gripping, nor free-swinging, i.e., a transient state.

[0079] Figure 12 is a table showing the relationship between the range in which the piston 91 is located, the detection results of the first detection unit 61 and the second detection unit 62, and the state of the hand 96. In Figure 12, "On" is displayed when the first detection unit 61 and the second detection unit 62 detect the piston 91, and "Off" is displayed when the first detection unit 61 and the second detection unit 62 do not detect the piston 91.

[0080] As shown in Figure 12, when the first detection unit 61 is off and the second detection unit 62 is on, it can be determined that the hand 96 is not gripping. When the first detection unit 61 is on and the second detection unit 62 is off, it can be determined that the hand 96 is gripping. When both the first detection unit 61 and the second detection unit 62 are off, it can be determined that the hand 96 is not vibrating.

[0081] In other words, taking into account the stroke distance of the piston 91 and the detection width of the first detection unit 61 and the second detection unit 62, the first detection unit 61 and the second detection unit 62 are positioned in the cylinder 90 such that when the hand 96 is not gripping, the first detection unit 61 is turned off and the second detection unit 62 is turned on; when the hand 96 is gripping, the first detection unit 61 is turned on and the second detection unit 62 is turned off; and when the hand 96 is free, both the first detection unit 61 and the second detection unit 62 are turned off.

[0082] Furthermore, when the first detection unit 61 and the second detection unit 62 are ON, it can be determined that the hand 96 is in a transient state, changing from a gripping state to a non-gripping state or from a non-gripping state to a gripping state. The time the hand 96 is in a transient state is short, and it usually immediately returns to either a gripping state or a non-gripping state.

[0083] Figure 13 is a partially enlarged view showing the tool transport path 51 between the replacement position arm 6c of the first magazine 6 and the replacement position arm 8d of the second magazine 8. As shown in Figure 13, the tool transport device 9 transports the tool 50 so that the center of the tool 50 moves along the tool transport path 51. The tool transport path 51 is a line segment. One end of the tool transport path 51 is located inside the replacement position arm 6c, and the other end is located inside the replacement position arm 8d. The position of one end of the tool transport path 51 is the first replacement position P1. The first replacement position P1 is the center position of the tool 50 held by the replacement position arm 6c. The position of the other end of the tool transport path 51 is the second replacement position P2. The second replacement position P2 is the center position of the tool 50 held by the replacement position arm 8d. P3 in Figure 13 is a non-interference position.

[0084] The non-interference position P3 is located away from the second swap position P2 and on the opposite side of the first swap position P1, and overlaps with the second magazine 8. When pod 9f is in the non-interference position P3, the first magazine 6 and the second magazine 8 can rotate without interfering with pod 9f.

[0085] As described above, the first gripping position K1 is the position where the pod 9f grasps the tool 50 gripped by the replacement position arm 6c. The first replacement position P1 is the position where the replacement position arm 6c grips the tool 50. The first gripping position K1 and the first replacement position P1 are different positions in the axial direction of the tool 50 gripped by the replacement position arm 6c, but are the same position in the radial direction of the tool 50 gripped by the replacement position arm 6c. That is, the first gripping position K1 and the first replacement position P1 are overlapping positions when viewed from the axial direction of the tool 50 gripped by the replacement position arm 6c.

[0086] As described above, the second gripping position K2 is the position where the pod 9f grasps the tool 50 gripped by the replacement position arm 8d. The second replacement position P2 is the position where the replacement position arm 8d grips the tool 50. The second gripping position K2 and the second replacement position P2 are different positions in the axial direction of the tool 50 gripped by the replacement position arm 8d, but are the same position in the radial direction of the tool 50 gripped by the replacement position arm 8d. That is, the second gripping position K2 and the second replacement position P2 are overlapping positions when viewed from the axial direction of the tool 50 gripped by the replacement position arm 8d. In this embodiment, the tool transport device 9 transports the tool linearly, but the transport of the tool is not limited to linear transport. For example, a tool transport device equipped with an arm capable of linear and rotational motion may be used. In this case, the first replacement position, the second replacement position and the non-interference position are not necessarily located on the same straight line.

[0087] Figure 14 is a block diagram showing a control device 60, motors 6f, 9a, 8c, a first detection unit 61, a second detection unit 62, a solenoid valve 63, a notification unit 64, and an operation unit 66. The machine tool is equipped with a control device 60. The control device 60 includes a control unit 60a, a main memory unit 60b, an auxiliary memory unit 60c, and an input / output interface (input / output I / F) 60d. The control unit 60a includes, for example, a processor or logic circuit. The processor includes, for example, a CPU, MPU, or GPU. The logic circuit includes, for example, an FPGA or ASIC. The main memory unit 60b includes, for example, RAM. The auxiliary memory unit 60c includes a rewritable storage device, such as an EEPROM, flash ROM, or hard disk. The input / output I / F 60d is an interface connected to the motors 6f, 9a, 8c, the first detection unit 61, the second detection unit 62, the solenoid valve 63, the notification unit 64, and the operation panel 41b, etc.

[0088] The notification unit 64 is, for example, a display screen, a lamp, a buzzer, etc., and when an abnormality is detected, it notifies the abnormality by displaying information indicating the abnormality, lighting or flashing a light, or making a sound.

[0089] The auxiliary storage unit 60c stores the control program, i.e., the program product. The control unit 60a reads the control program from the auxiliary storage unit 60c into the main storage unit 60b and executes it. The control program includes workpiece machining commands, transport commands for transporting tools between the first magazine 6 and the second magazines 7 and 8, etc. The control unit 60a stores the data generated by the execution of the control program in the auxiliary storage unit 60c. The control unit 60a transmits drive signals to the motors 6f, 9a, 8c, solenoid valve 63 and notification unit 64 via the input / output interface 60d as needed. The control unit 60a receives detection results from the first detection unit 61 and the second detection unit 62, etc., via the input / output interface 60d.

[0090] The auxiliary storage unit 60c stores arm identification numbers that identify each arm in the first magazine 6 and the second magazines 7 and 8, and tool identification numbers that identify the tools. The arm identification numbers and tool identification numbers correspond to each other. When a tool is transported between the first magazine 6 and the second magazines 7 and 8, the control unit 60a updates the arm identification numbers and tool identification numbers to reflect the correspondence after the transport. Note that tool identification numbers are not stored for empty arms. The tool identification number is an example of information used to identify a tool, and tools may also be identified by characters. The arm identification number is an example of information used to identify an arm, and arms may also be identified by characters.

[0091] When an operator attaches tool 50 to arm 6b of the first magazine 6, the operator operates the control unit 66 to input the tool identification number of the attached tool 50 and the arm identification number of arm 6b to which the tool 50 is attached, linking them together. The auxiliary storage unit 60c stores the input arm identification number and tool identification number. When an operator removes tool 50 from arm 6b of the first magazine 6, the operator operates the control unit 66 to delete the tool identification number linked to the arm identification number of arm 6b from which the tool 50 was removed.

[0092] As mentioned above, the cover 52 prevents the operator from attaching or detaching tools to the arms of the second magazines 7 and 8. The attachment and detachment of tools to and from the second magazines 7 and 8 is performed between the first magazine 6 and the second magazines 7 and 8 by the tool transport device 9.

[0093] The control program is stored in a storage medium 65, such as an optical disc, flash memory, or hard disk, and may be downloaded from the storage medium 65 to the auxiliary storage unit 60c. Alternatively, it may be downloaded from an external server to the auxiliary storage unit 60c via a network (not shown). Processing by the control program, such as the tool transport process described later, may be implemented by a server or terminal connected to the control device 60 via a network, or by distributed processing by a server and other devices, such as a terminal or a second server.

[0094] The control unit 60a outputs a command to the pod 9f to enter a gripping state at the first replacement position P1. If the first detection unit 61 and the second detection unit 62 determine that the pod 9f is in an empty state, the control unit 60a sets an empty flag to indicate that the arm 6b located at the first replacement position P1 is empty. That is, the control unit 60a stores the empty flag in the auxiliary storage unit 60c, linked to the arm identification number of the arm 6b located at the first replacement position P1. The empty flag constitutes a toolless flag.

[0095] When the tool 50 is removed from the arm 6b located at the first replacement position P1, the control unit 60a sets an empty flag. That is, the control unit 60a stores the empty flag in the auxiliary storage unit 60c, linked to the arm identification number of the arm 6b located at the first replacement position P1. The empty flag constitutes the removed flag. In this embodiment, the auxiliary storage unit 60c stores a common empty flag as both the tool-less flag and the removed flag, but the tool-less flag and the removed flag may be stored separately.

[0096] When the tool 50 is transported to arm 6b, which has an empty flag set at the first swap position P1, the control unit 60a removes the empty flag. That is, the control unit 60a deletes the empty flag associated with the arm identification number of arm 6b located at the first swap position P1 from the auxiliary storage unit 60c.

[0097] The control unit 60a outputs a command to the pod 9f to enter a gripping state at the second replacement position P2. If the first detection unit 61 and the second detection unit 62 determine that the pod 9f is in an empty state, the control unit 60a sets an empty flag to indicate that the arm 8b located at the second replacement position P2 is empty. That is, the control unit 60a stores the empty flag in the auxiliary storage unit 60c, linked to the arm identification number of the arm 8b located at the second replacement position P2. The empty flag constitutes a toolless flag.

[0098] When the tool 50 is removed from the arm 8b located at the second swap position P2, the control unit 60a sets an empty flag. That is, the control unit 60a stores the empty flag in the auxiliary storage unit 60c, linked to the arm identification number of the arm 8b located at the second swap position P2. The empty flag constitutes a removed flag.

[0099] When the tool 50 is transported to arm 8b, which has an empty flag set at the second swap position P2, the control unit 60a removes the empty flag. That is, the control unit 60a deletes the empty flag associated with the arm identification number of arm 8b located at the second swap position P2 from the auxiliary storage unit 60c.

[0100] When the control unit 60a detects that the opening / closing door 41a is open by the opening / closing detector 41c, it executes a process to remove the empty flag for the arm 6b that is in a position where a tool can be attached to the first magazine 6, for example, the position where a tool can be attached to the spindle 10a of the first magazine 6 or a position where a tool can be attached to a notch. That is, the empty flag associated with the arm identification number of the arm 6b that is in a position where a tool can be attached to the spindle 10a is deleted from the auxiliary storage unit 60c. If the opening / closing door 41a is open, there is a risk that an operator may manually attach a tool 50 to an empty arm 6b in a position where a tool can be attached. Also, if the system is in maintenance mode, there is a risk that an operator may open the opening / closing door 41a.

[0101] Figures 15 to 17 are flowcharts illustrating the tool transport process performed by the control unit 60a. When the control unit 60a receives a transport command, it executes the tool transport process. The tool transport process constitutes the tool movement process. In the initial state, the pod 9f is located at the non-interference position P3. The control unit 60a positions the spindle 10a at the origin (S1), drives the motor 6f to position the arm 6b of the first magazine 6, as specified in the transport command, at the first replacement position P1 (S2). The process performed by the control unit 60a in step S2 constitutes the first process. The control unit 60a opens the shutter of the opening 52a (S3), switches the solenoid valve 63 to the second position, i.e., switches the pod 9f to the non-gripping state (S4). The control unit 60a determines whether or not it is unnecessary to transport the tool from the first magazine 6 to the second magazine 8 (S5).

[0102] For example, the control unit 60a determines that it is unnecessary to transport the tool from the first magazine 6 to the second magazine 8 if an empty flag is set in association with the arm identification number of arm 6b at the first replacement position P1, or if no tool identification number is stored in association with the arm identification number of arm 6b at the first replacement position P1.

[0103] If it is determined that the transfer of the tool from the first magazine 6 to the second magazine 8 is not unnecessary (S5: NO), the control unit 60a moves the pod 9f to the first exchange position P1 (S6). The processing in step S6 by the control unit 60a constitutes the second process. The control unit 60a switches the solenoid valve 63 to the first position, that is, switches the pod 9f to the gripping state (S7). In step S7, the control unit 60a detects the presence or absence of a tool in the arm 6b positioned at the first exchange position P1 based on the detection results of the first detection unit 61 and the second detection unit 62. The control unit 60a determines whether the detection results of the first detection unit 61 and the second detection unit 62 correspond to the presence or absence of a tool identification number (S8). The presence of a tool identification number corresponds to information indicating that the tool is stored, and the absence of a tool identification number corresponds to information indicating that the tool is not stored.

[0104] The control unit 60a determines that the detection result corresponds to the presence or absence of a tool identification number if the detection results of the first detection unit 61 and the second detection unit 62 indicate a gripping state and a tool identification number is stored in association with the arm identification number of the arm 6b at the first replacement position P1. The control unit 60a determines that the detection result corresponds to the presence or absence of a tool identification number if the detection results of the first detection unit 61 and the second detection unit 62 indicate an idle state and a tool identification number is not stored in association with the arm identification number of the arm 6b at the first replacement position P1.

[0105] The control unit 60a determines that if the detection results of the first detection unit 61 and the second detection unit 62 indicate a gripping state, and the tool identification number is not stored in association with the arm identification number of the arm 6b at the first replacement position P1, then the detection result and the presence or absence of the tool identification number do not correspond. In this case, there is a possibility that an abnormality has occurred in the first detection unit 61 and the second detection unit 62. The control unit 60a determines that if the detection results of the first detection unit 61 and the second detection unit 62 indicate an empty state, and the tool identification number is stored in association with the arm identification number of the arm 6b at the first replacement position P1, then the detection result and the presence or absence of the tool identification number do not correspond. In this case, there is a possibility that the tool has fallen out of the pod 9f.

[0106] If the detection results of the first detection unit 61 and the second detection unit 62 do not correspond to the presence or absence of a tool identification number (S8: NO), the control unit 60a performs abnormality processing (S12) and terminates the process. The abnormality processing includes, for example, the notification unit 64 displaying information such as that the transport process cannot be performed, that the machine tool has stopped, that there is a possibility of an abnormality in the detection unit, or that the tool has fallen out of the pod 9f, as well as lighting or flashing a light, or making a sound.

[0107] If the first detection unit 61 and the second detection unit 62 determine that there is a correspondence between the presence or absence of a tool identification number (S8: YES), the control unit 60a determines whether the arm 6b at the first replacement position P1 is empty or not (S9). The control unit 60a determines that the arm 6b at the first replacement position P1 is empty if the tool identification number is not stored in association with the arm identification number of the arm 6b at the first replacement position P1. If the tool identification number is stored in association with the arm identification number of the arm 6b at the first replacement position P1, the control unit 60a determines that the arm 6b at the first replacement position P1 is not empty. The processing by the control unit 60a in steps S7 to S9 constitutes the detection process.

[0108] If it is determined that the arm 6b at the first exchange position P1 is not empty (S9: NO), the control unit 60a moves the pod 9f to the second exchange position P2 (S10) and switches the solenoid valve 63 to the second position, i.e., switches the pod 9f to the non-gripping state (S11). The control unit 60a then removes the empty flag set for the arm 8b at the second exchange position P2 (S14) and moves the pod 9f to the non-interference position P3 (S15). The processing in step S15 by the control unit 60a constitutes the fourth process.

[0109] The control unit 60a sets an empty flag for the arm 6b at the first swap position P1 (S16). If it is determined in step S9 that the arm 6b at the first swap position P1 is empty (S9: YES), the pod 9f is moved to the non-interference position P3 (S13). The processing by the control unit 60a in step S13 constitutes the third process. An empty flag is set for the arm 6b at the first swap position P1 (S16).

[0110] After the processing in step S16, the control unit 60a drives the motor 8c to position the arm 8b of the second magazine 8, as specified in the transport command, at the second swap position P2 (S17). If it is determined in step S5 that it is unnecessary to transport the tool from the first magazine 6 to the second magazine 8 (S5: YES), the control unit 60a drives the motor 8c to position the arm 8b of the second magazine 8, as specified in the transport command, at the second swap position P2 (S17). The processing in step S17 by the control unit 60a constitutes the fifth process. As will be described later, if it is determined to be YES in step S18 and YES in step S29, the processing in step S17 is performed before the processing in step S2, that is, before the first process is performed.

[0111] After processing in step S17, the control unit 60a determines whether or not it is unnecessary to transport the tool from the second magazine 8 to the first magazine 6 (S18). For example, if an empty flag is set in association with the arm identification number of arm 8b at the second swapping position P2, or if no tool identification number is stored in association with the arm identification number of arm 8b at the second swapping position P2, the control unit 60a determines that it is unnecessary to transport the tool from the second magazine 8 to the first magazine 6.

[0112] If it is determined that the transfer of the tool from the second magazine 8 to the first magazine 6 is not unnecessary (S18: NO), the control unit 60a moves the pod 9f to the second exchange position P2 (S19) and switches the solenoid valve 63 to the first position, that is, switches the pod 9f to the gripping state (S20). The control unit 60a determines whether the detection results of the first detection unit 61 and the second detection unit 62 correspond to the presence or absence of a tool identification number (S21).

[0113] The control unit 60a determines that the detection result corresponds to the presence or absence of a tool identification number if the detection results of the first detection unit 61 and the second detection unit 62 indicate a gripping state and a tool identification number is stored in association with the arm identification number of the arm 8b at the second replacement position P2. The control unit 60a determines that the detection result corresponds to the presence or absence of a tool identification number if the detection results of the first detection unit 61 and the second detection unit 62 indicate an idle state and a tool identification number is not stored in association with the arm identification number of the arm 8b at the second replacement position P2.

[0114] The control unit 60a determines that if the detection results of the first detection unit 61 and the second detection unit 62 indicate a gripping state, and the tool identification number is not stored in association with the arm identification number of the arm 8b at the second replacement position P2, then the detection result and the presence or absence of the tool identification number do not correspond. In this case, there is a possibility that an abnormality has occurred in the first detection unit 61 and the second detection unit 62. The control unit 60a determines that if the detection results of the first detection unit 61 and the second detection unit 62 indicate an empty state, and the tool identification number is stored in association with the arm identification number of the arm 8b at the second replacement position P2, then the detection result and the presence or absence of the tool identification number do not correspond. In this case, there is a possibility that the tool has fallen out of the pod 9f.

[0115] If the detection results of the first detection unit 61 and the second detection unit 62 do not correspond to the presence or absence of a tool identification number (S21: NO), the control unit 60a performs abnormality processing (S25) and terminates the process. The abnormality processing includes, for example, the notification unit 64 displaying information such as that the transport process cannot be performed, that the machine tool has stopped, that there is a possibility of an abnormality in the detection unit, or that the tool has fallen out of the pod 9f, as well as lighting or flashing a light, or making a sound.

[0116] If the first detection unit 61 and the second detection unit 62 determine that the presence or absence of a tool identification number corresponds to the detection results (S21: YES), the control unit 60a determines whether the arm 8b at the second replacement position P2 is empty or not (S22). The control unit 60a determines that the arm 8b at the second replacement position P2 is empty if the tool identification number is not stored in association with the arm identification number of the arm 8b at the second replacement position P2. If the tool identification number is stored in association with the arm identification number of the arm 8b at the second replacement position P2, the control unit 60a determines that the arm 8b at the second replacement position P2 is not empty. The processing by the control unit 60a in steps S20 to S22 constitutes the second detection process.

[0117] If it is determined that the arm 8b at the second exchange position P2 is not empty (S22: NO), the control unit 60a moves the pod 9f to the first exchange position P1 (S23). The processing in step S23 by the control unit 60a constitutes the sixth process. As will be described later, if it is determined to be YES in step S29, the processing in step S23 is performed before the processing in step S2, that is, before the first process is performed. The control unit 60a switches the solenoid valve 63 to the second position, that is, switches the pod 9f to the non-gripping state (S24). The control unit 60a removes the empty flag set for the arm 6b at the first exchange position P1 (S27) and moves the pod 9f to the non-interference position P3 (S28). The control unit 60a determines whether or not there is a next transport command (S29).

[0118] If, in step S18, it is determined that it is not necessary to transport the tool from the second magazine 8 to the first magazine 6 (S18: YES), the control unit 60a determines whether or not there is a next transport command (S29).

[0119] In step S22, if it is determined that the arm 8b at the second swap position P2 is empty (S22: YES), the control unit 60a moves the pod 9f to the non-interference position P3 (S26) and determines whether or not there is a next transport command (S29).

[0120] In step S29, if it is determined that there is a next transport command (S29: YES), the control unit 60a returns to step S2. That is, the control unit 60a repeatedly executes the tool transport process, i.e., the tool movement process. If it is determined that there is no next transport command (S29: NO), the control unit 60a closes the shutter (S30) and determines whether a tool to be mounted on the spindle 10a is specified in the transport command (S31). If it is determined that a tool to be mounted on the spindle 10a is not specified (S31: NO), the control unit 60a terminates the process. If it is determined that a tool to be mounted on the spindle 10a is specified (S31: YES), the control unit 60a positions the arm 6b containing the tool to be mounted on the spindle 10a to the position to be mounted on the spindle 10a, i.e., the lowest position of the first magazine 6 (S32), lowers the spindle 10a (S33), and terminates the process.

[0121] Figure 18 is a flowchart illustrating the monitoring process for checking whether a tool can be attached to the first magazine 6. The monitoring process is a subroutine and is executed in parallel with the tool transport process. The control unit 60a determines whether or not it is possible for the operator to attach a tool to the first magazine 6 (S41). If the control unit 60a receives a detection result from the open / close detector 41c indicating that the open / close door 41a is open, or if it is in maintenance mode, it determines that it is possible for the operator to attach a tool to the first magazine 6. If it determines that it is not possible for the operator to attach a tool to the first magazine 6 (S41: NO), the control unit 60a terminates the process.

[0122] If the control unit 60a determines that the operator can attach a tool to the first magazine 6 (S41: YES), it selects an arm 6b to which the tool can be attached (S42), removes the empty flag set for the selected arm 6b (S43), and terminates the process.

[0123] Furthermore, if the control unit 60a determines that the operator can attach a tool to the first magazine 6, it may also execute a process to remove the empty flag for arms 6b that are not in positions where a tool can be attached. This is because the operator can manually rotate the first magazine 6 to move each empty arm 6b to a position where a tool can be attached and then attach the tool 50 to each empty arm 6b.

[0124] Tool transport is also performed between the first magazine 6 and the second magazine 7. Tool transport between the first magazine 6 and the second magazine 7 is carried out in the same manner as tool transport between the first magazine 6 and the second magazine 8.

[0125] In the machine tool according to this embodiment, a first detection unit 61 and a second detection unit 62 are provided in the tool transport device 9 to detect the presence or absence of a tool, and the tool is transported between the first magazine 6 and the second magazine 8. Furthermore, if the absence of a tool is detected in the arm 6b located at the first exchange position P1, the control device 60 transports the pod 9f to a non-interference position. By providing the first detection unit 61 and the second detection unit 62 in the tool transport device 9, manufacturing costs can be reduced compared to providing them in each arm 6b and each arm 8b. In addition, tools can be transported between the first magazine 6 and the second magazine 8 while avoiding collisions between tools. Furthermore, if there is no tool at the first exchange position P1, the process of transporting the pod 9f from the first exchange position P1 to the second exchange position P2 is not performed, thereby improving transport efficiency.

[0126] Furthermore, if it is determined that the arm 6b, which was assigned to the first exchange position P1 in the previous transport process, has an empty flag, i.e., a toolless flag, set, then in the current transport process, the transport process of the pod 9f to the first exchange position P1 and the process of detecting the presence or absence of a tool on the arm 6b positioned at the first exchange position P1 can be omitted, thereby improving transport efficiency.

[0127] Furthermore, only when arm 6b has a tool, pod 9f can be transported from the first exchange position P1 to the second exchange position P2, and then transported to the non-interference position P3, allowing the second magazine 8 to determine the second exchange position P2 of arm 8b, thereby improving transport efficiency.

[0128] Furthermore, if it is determined that the arm 6b, which was assigned to the first replacement position P1 in the previous transport process, has an empty flag, i.e., a removed flag, then in the current transport process, the transport process of the pod 9f to the first replacement position P1 and the process of detecting the presence or absence of a tool on the arm 6b positioned at the first replacement position P1 can be omitted, thereby improving transport efficiency.

[0129] Furthermore, if the presence or absence of a tool detected by the detection process for arm 6b positioned at the first replacement position P1 does not correspond to the presence or absence of a tool indicated by the tool identification number stored in the auxiliary storage unit 60c, an abnormality process is executed, thereby notifying the operator of the abnormality.

[0130] Furthermore, the system identifies the designated arm 8b to the second swap position P2, detects the presence or absence of a tool on arm 8b positioned at the second swap position P2, and if the presence of a tool is detected, it performs the transport operation of pod 9f from the second swap position P2 to the first swap position P1, and removes the empty flag, i.e., the no-tool flag, for arm 6b positioned at the first swap position P1. Thus, the presence or absence of a tool can be matched with the setting and removal of the empty flag.

[0131] Furthermore, if it is possible to manually attach tools to arm 6b, the empty flag, i.e., the no-tool flag, set on arm 6b is cleared. This ensures that even if a tool is attached to arm 6b with the empty flag set and the operator forgets to set a tool identification number on arm 6b, the tools will not interfere with each other when subsequent tool transport commands are issued.

[0132] Furthermore, if it is possible to manually attach tools to arm 6b, the empty flag, i.e., the removed flag, set on arm 6b is released. This ensures that even if a tool is attached to arm 6b with the empty flag set and the operator forgets to set the tool identification number on arm 6b, the tools will not interfere with each other when subsequent tool transport commands are issued.

[0133] Furthermore, the cover 52 prevents the operator from attaching or detaching tools to the arms of the second magazines 7 and 8. Tool transport between the first magazine 6 and the second magazines 7 and 8 is only possible by the tool transport device 9. Therefore, it is possible to prevent tools without a tool identification number from being attached to the second magazines 7 and 8.

[0134] The embodiments disclosed herein should be considered illustrative and not restrictive in all respects. The scope of the present invention is intended to include all modifications within the claims and equivalents thereof. The matters described in each embodiment can be combined with one another. Furthermore, the independent and dependent claims described in the claims can be combined with one another in any combination, regardless of the form of reference. In addition, the claims use a multi-claim format in which claims refer to two or more other claims (multi-claim format), but are not limited thereto. They may also be described using a multi-claim format in which at least one multi-claim refers to another multi-claim (multi-multi-claim format). [Explanation of symbols]

[0135] 6 First Magazine 6b Arm (First storage section) 8 Second Magazine 8b Arm (Second storage compartment) 9. Tool conveying device 9f Pod (Grip part) 9a motor 9b Ball screw 9c nut 9d orbit 9e Slider 9g connection part 52 Cover (Regulatory Cover) 60 Control device 61 First detection unit 62 Second detection unit

Claims

1. A tool transport device capable of transporting a gripping part for gripping a tool to a first magazine having a plurality of first storage compartments for storing tools, a second magazine having a plurality of second storage compartments for storing tools, a first replacement position for removing or storing tools in the first magazine, a second replacement position for removing or storing tools in the second magazine, and a non-interference position different from the first and second replacement positions and which does not interfere with the first and second magazines, and a control device provided in the tool transport device for controlling a detection unit for detecting the presence or absence of a tool based on the gripping state of the gripping part, When executing a command to move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, In the first magazine, a first process is performed to locate the designated first storage unit at the first replacement position. After the execution of the first process, the tool transport device performs a second process in which it transports the gripping portion to the first replacement position. After the execution of the second process, the detection unit performs a detection process to detect the presence or absence of a tool in the first storage unit located at the first replacement position. If the detection process detects the absence of a tool, the tool transport device performs a third process, which involves transporting the gripping portion from the first replacement position to the non-interference position. Control device.

2. The first to third processes include a tool transfer process in which a tool is moved from one of the first magazine and the second magazine to the other of the first magazine and the second magazine. The tool movement process described above is repeatedly executed, In the first tool movement process, a tool absence flag is set in association with the first storage unit in which the detection unit has detected the absence of a tool. When the second tool movement process is performed after the first tool movement process, after the first process is performed, it is determined whether the toolless flag is set for the first storage unit that has been assigned to the first replacement position. If it is determined that the tool-less flag is set for the first storage unit located at the first replacement position, the second process and the detection process are omitted. The control device according to claim 1.

3. If the presence of a tool is detected in the detection process, the tool transport device performs a fourth process in which it transports the gripping part from the first replacement position to the second replacement position, and then transports the gripping part from the second replacement position to the non-interference position. The control device according to claim 1.

4. The first to fourth processes include a tool transfer process in which a tool is moved from one of the first magazine and the second magazine to the other of the first magazine and the second magazine. The tool movement process described above is repeatedly executed, In the first tool movement process, a removed flag is set in association with the first storage unit in which the presence of a tool has been detected by the detection unit, indicating that the tool has been removed by the tool transport device's transport operation of the gripping unit from the first replacement position to the second replacement position. When the second tool movement process is performed after the first tool movement process, after the first process is performed, it is determined whether the removed flag is set for the first storage unit that has been assigned to the first replacement position. If it is determined that the removed flag is set for the first storage unit located at the first replacement position, the second process and the detection process are omitted. The control device according to claim 3.

5. Each first storage compartment is equipped with a storage unit that stores information indicating whether a tool is stored or not. If the presence or absence of the tool detected in the detection process for the first storage unit located at the first replacement position does not correspond to whether the tool is stored or not as indicated by the information, then an error process is executed. The control device according to any one of claims 1 to 4.

6. The tool movement process includes a fifth process and a sixth process that are performed before the execution of the first process or after the execution of the third process. The fifth process is the process of locating the designated second storage unit in the second magazine to the second replacement position. The sixth process is a process in which, after the execution of the fifth process, the tool transport device performs a transport operation of the gripping portion from the second replacement position to the first replacement position. After the execution of the fifth process and before the execution of the sixth process, the detection unit performs a second detection process to detect the presence or absence of a tool in the second storage unit located at the second replacement position. If the presence of a tool is detected in the second detection process, the setting of the "no tool" flag for the first storage unit located at the first replacement position is removed after the execution of the sixth process. The control device according to claim 2.

7. Determine whether or not it is possible to manually attach the tool to the first storage compartment. If it is determined that a tool can be manually attached to the first storage compartment, the tool-less flag set for the first storage compartment is released. The control device according to claim 2.

8. Determine whether or not it is possible to manually attach the tool to the first storage compartment. If it is determined that a tool can be manually attached to the first storage compartment, the removed flag set on the first storage compartment is released. The control device according to claim 4.

9. A machine tool comprising: a first magazine having a plurality of first storage compartments for storing tools; a second magazine having a plurality of second storage compartments for storing tools; a tool transport device capable of transporting a gripping part for gripping a tool to a first replacement position for removing or storing tools in the first magazine; a second replacement position for removing or storing tools in the second magazine; and a non-interference position different from the first and second replacement positions and which does not interfere with the first and second magazines; a detection unit provided in the tool transport device for detecting the presence or absence of a tool based on the gripping state of the gripping part; and a control device for controlling the first magazine, the second magazine, the tool transport device, and the detection unit. The control device is When executing a command to move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, In the first magazine, a first process is performed to locate the designated first storage unit at the first replacement position. After the execution of the first process, the tool transport device performs a second process in which it transports the gripping portion to the first replacement position. After the execution of the second process, the detection unit performs a detection process to detect the presence or absence of a tool in the first storage unit located at the first replacement position. If the detection process detects the absence of a tool, the tool transport device performs a third process, which involves transporting the gripping portion from the first replacement position to the non-interference position. Machine tools.

10. The system includes a restricting cover that prevents tools from being attached to the second magazine without using the tool transport device. The machine tool according to claim 9.

11. A control method comprising: a first magazine having a plurality of first storage compartments for storing tools; a second magazine having a plurality of second storage compartments for storing tools; a tool transport device capable of transporting a gripping part for gripping a tool to a first replacement position for removing or storing tools in the first magazine; a second replacement position for removing or storing tools in the second magazine; and a non-interference position different from the first and second replacement positions and which does not interfere with the first and second magazines; and a detection unit provided in the tool transport device for detecting the presence or absence of a tool based on the gripping state of the gripping part, When executing a command to move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, In the first magazine, a first process is performed to locate the designated first storage unit at the first replacement position. After the execution of the first process, the tool transport device performs a second process in which it transports the gripping portion to the first replacement position. After the execution of the second process, the detection unit performs a detection process to detect the presence or absence of a tool in the first storage unit located at the first replacement position. If the detection process detects the absence of a tool, the tool transport device performs a third process, which involves transporting the gripping portion from the first replacement position to the non-interference position. Control method.

12. A computer program executable by a control device that controls a first magazine having a plurality of first storage compartments for storing tools, a second magazine having a plurality of second storage compartments for storing tools, a tool transport device capable of transporting a gripping part for gripping a tool to a first replacement position for removing or storing tools in the first magazine, a second replacement position for removing or storing tools in the second magazine, and a non-interference position different from the first and second replacement positions and that does not interfere with the first and second magazines, and a detection unit provided in the tool transport device for detecting the presence or absence of a tool based on the gripping state of the gripping part, The control device, When executing a command to move a tool from one of the first magazine and the second magazine to the other of the first magazine and the second magazine, In the first magazine, a first process is performed to locate the designated first storage unit at the first replacement position. After the execution of the first process, the tool transport device performs a second process in which it transports the gripping portion to the first replacement position. After the execution of the second process, the detection unit performs a detection process to detect the presence or absence of a tool in the first storage unit located at the first replacement position. If the detection process detects the absence of a tool, the tool transport device performs a third process, which involves transporting the gripping portion from the first replacement position to the non-interference position. A computer program that executes a process.

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