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

Abstract

To provide a control device that can reduce the need for manual recovery operations. [Solution] The control device controls a machine tool that includes a first magazine having a first storage compartment, a second magazine having a second storage compartment, a tool transport device with a movable gripping unit that grips a tool at a first replacement position, a second replacement position, and a non-interference position, and a detection unit that detects the presence or absence of a tool. When executing a command to move a tool from one of the first magazines to the other, the control device executes a movement of the gripping unit to the first replacement position or the second replacement position, detects the presence or absence of a tool in the first storage compartment at the first replacement position or the presence or absence of a tool in the second storage compartment at the second replacement position, determines whether there is an abnormality in the first storage compartment or the second storage compartment based on the detection result, and if it is determined that there is an abnormality, it instructs the tool transport device to execute a movement of the gripping unit from the first replacement position or the second replacement position to a non-interference position.

Description

[Technical Field]

[0001] The present technology relates to a control device that controls machining of a workpiece, a machine tool, a control method, and a computer program. [Background Art]

[0002] A machine tool capable of exchanging tools between a plurality of tool magazines has been proposed. The machine tool includes a plurality of tool magazines, and a switch provided in a tool holder of each of the plurality of tool magazines for detecting the presence or absence of a tool. The machine tool checks the presence or absence state of a tool in each tool holder based on the detection result of the switch. When exchanging tools, if the presence or absence state of a tool in the tool holder is not normal, a warning is issued or an emergency stop is performed (see Patent Document 1). [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent No. 5503908 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] When a machine tool emergency stops, an operator has to manually perform a recovery operation.

[0005] The present disclosure has been made in view of such circumstances, and an object thereof is to provide a control device, a machine tool, a control method, and a computer program capable of reducing manual recovery operations. [Means for Solving the Problem]

[0006] A control device according to one embodiment of the present disclosure is a control device for controlling 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 moving 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; 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 for detecting the presence or absence of a tool based on the gripping state of the gripping part, wherein the gripping part can move from one of the first and second magazines to the first magazine and When a command is executed to move the tool to the other side of the second magazine, the following is performed: a first movement process in which the tool transport device performs a movement of the gripping part to the first replacement position or the second replacement position; a detection process in which, after the execution of the first movement process, the detection unit detects whether or not there is a tool in the first storage unit at the first replacement position, or whether or not there is a tool in the second storage unit at the second replacement position; a determination process in which, based on the detection result of the detection process, the detection unit determines whether or not there is an abnormality in the first storage unit or the second storage unit; and, if the determination process determines that there is an abnormality, a second movement process in which the tool transport device performs a movement of the gripping part from the first replacement position or the second replacement position to the non-interference position.

[0007] In this disclosure, if an abnormality occurs, the gripping portion is automatically moved to a non-interfering position.

[0008] A control device according to one embodiment of the present disclosure includes a storage unit that stores information indicating the presence or absence of tools in a plurality of first storage units and information indicating the presence or absence of tools in a plurality of second storage units, and in the determination process, if the presence or absence of tools in the first storage unit detected in the detection process does not match the presence or absence of tools in the first storage unit stored in the storage unit, or if the presence or absence of tools in the second storage unit detected in the detection process does not match the presence or absence of tools in the second storage unit stored in the storage unit, it is determined that there is an abnormality.

[0009] In this disclosure, if the presence or absence of a tool in the first or second storage compartment detected does not match the presence or absence of a tool in the first or second storage compartment stored in the memory, it is determined that there is an abnormality.

[0010] In one embodiment of the present disclosure, the control device outputs a signal to notify of an abnormality if it determines in the determination process that an abnormality exists.

[0011] In this disclosure, if an abnormality is detected, the abnormality will be reported.

[0012] In one embodiment of the present disclosure, the control device drives the first magazine or the second magazine so that, after the execution of the second movement process, the first storage unit or the second storage unit which was determined to have an abnormality is positioned in a location where a tool can be attached to or detached.

[0013] In this disclosure, by positioning the tool in a location where it can be attached and detached, the operator can check the first storage unit or the second storage unit that has been determined to be abnormal.

[0014] In one embodiment of the present disclosure, if the first movement process, the detection process, and the determination process are executed again on the first storage unit or the second storage unit which has been determined to be free of abnormalities in the determination process, the control device stops the movement operation of the gripping unit if it is determined that there is an abnormality.

[0015] If an abnormality is detected after initially determining that there is no abnormality, it is highly likely that a physical abnormality has occurred in the machine tool. In this disclosure, if there is a high probability that a physical abnormality has occurred in the machine tool, the movement of the gripping part is stopped.

[0016] In one embodiment of the present disclosure, the control device includes a machine tool comprising a cover that covers the first magazine and the second magazine, an opening / closing door attached to the cover, and an opening / closing detection unit that detects the opening and closing of the opening / closing door. If the first storage unit or the second storage unit is determined to be free of abnormalities in the determination process, the first movement process, the detection process, and the determination process are executed again. If it is determined that there is an abnormality, and the opening / closing detection unit has not detected the opening of the opening / closing door during the two determination processes, the movement of the gripping unit is stopped. If the opening / closing detection unit has detected the opening of the opening / closing door during the two determination processes, the second movement process is executed.

[0017] In this disclosure, if there is a high probability that a physical abnormality has occurred in the machine tool, the movement of the gripping part is stopped, and if there is a high probability that the abnormality has occurred due to an error in the operator's information input, the gripping part is moved to a non-interference position.

[0018] A control device according to one embodiment of the present disclosure allows for manual attachment and detachment of a tool to the first magazine, and includes a restricting cover that restricts the attachment and detachment of a tool to the second magazine without using the tool transport device. The first movement process performs a movement operation of the gripping part to the second replacement position relative to the tool transport device. The detection process detects the presence or absence of a tool in the second storage unit at the second replacement position. The determination process determines whether or not there is an abnormality in the second storage unit based on the detection result of the detection process. If an abnormality is determined in the determination process, the gripping part is stopped.

[0019] In this disclosure, if an abnormality occurs in the second magazine, i.e., the magazine that the operator does not normally attach or detach tools to, it is highly likely that a physical abnormality has occurred in the machine tool, and therefore the movement of the gripping part is stopped.

[0020] In one embodiment of the present disclosure, the control device, in the second movement process, releases the gripping operation of the tool by the gripping part, and then performs the movement operation of the gripping part to the non-interference position.

[0021] In this disclosure, the gripping portion is moved to a non-interfering position while the tool is not being gripped.

[0022] A machine tool according to one embodiment of the present disclosure comprises: 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 moving 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; a detection unit for detecting the presence or absence of a tool based on the gripping state of the gripping part; and a control device, wherein the control device moves from one of the first and second magazines to the first and second magazines. When a command is executed to move a tool to the other side of the second magazine, the following are performed: a first movement process in which the tool transport device performs a movement of the gripping part to the first replacement position or the second replacement position; a detection process in which, after the execution of the first movement process, the detection unit detects whether or not there is a tool in the first storage unit at the first replacement position, or whether or not there is a tool in the second storage unit at the second replacement position; a determination process in which, based on the detection result of the detection process, the device determines whether or not there is an abnormality in the first storage unit or the second storage unit; and, if the determination process determines that there is an abnormality, a second movement process in which the tool transport device performs a movement of the gripping part from the first replacement position or the second replacement position to the non-interference position.

[0023] In this disclosure, if an abnormality occurs, the gripping portion is moved to a non-interfering position.

[0024] A control method according to an embodiment of the present disclosure is a control method for controlling a machine tool including: 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 first exchange position for removing or storing tools in the first magazine; a second exchange position for removing or storing tools in the second magazine; a non-interference position that is different from the first exchange position and the second exchange position and does not interfere with the first magazine and the second magazine; a tool transfer device capable of moving a gripping portion that grips a tool to any of the foregoing positions; and a detection portion that detects the presence or absence of a tool based on the gripping state of the gripping portion, wherein 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, the method comprises: causing the tool transfer device to perform an operation of moving the gripping portion to the first exchange position or the second exchange position; causing the detection portion to detect whether there is a tool in the first storage portion at the first exchange position or whether there is a tool in the second storage portion at the second exchange position; determining whether there is an abnormality in the first storage portion or the second storage portion based on the detection result; and when it is determined that there is an abnormality, causing the tool transfer device to perform an operation of moving the gripping portion from the first exchange position or the second exchange position to the non-interference position.

[0025] In the present disclosure, when an abnormality occurs, the gripping portion is moved to the non-interference position.

[0026] A computer program according to an embodiment of the present disclosure is executable by a control device that controls a machine tool including: 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 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; a non-interference position that is different from the first replacement position and the second replacement position and does not interfere with the first magazine and the second magazine; a tool transfer device capable of moving a gripping portion that grips a tool to the foregoing positions; and a detection portion that detects the presence or absence of a tool based on a gripping state of the gripping portion. The computer program causes the control device to execute the following processing: 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, causing the tool transfer device to execute an operation of moving the gripping portion to the first replacement position or the second replacement position; causing the detection portion to detect the presence or absence of a tool in the first storage portion at the first replacement position, or the presence or absence of a tool in the second storage portion at the second replacement position; determining whether there is an abnormality in the first storage portion or the second storage portion based on a detection result; and when it is determined that there is an abnormality, causing the tool transfer device to execute an operation of moving the gripping portion from the first replacement position or the second replacement position to the non-interference position.

[0027] In the present disclosure, when an abnormality occurs, the gripping portion is moved to the non-interference position. [Effects of the Invention]

[0028] In a control device, a machine tool, a control method and a computer program according to an embodiment of the present disclosure, when an abnormality occurs, the gripping portion is moved to the non-interference position. Therefore, manual movement of the gripping portion to the non-interference position, that is, manual recovery operation, can be reduced. [Brief Description of the Drawings]

[0029] [Figure 1] FIG. 1 is a schematic perspective view of the 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 the pod in a gripping state. [Figure 10] This is a schematic cross-sectional view of the pod in an air-powered 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 a control device, motor, first detection unit, second detection unit, solenoid valve, notification unit, and control panel. [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 is a flowchart illustrating the tool transport process performed by the control unit. [Figure 19] This is a flowchart illustrating the tool transport process by the control unit according to Embodiment 2. [Modes for carrying out the invention]

[0030] (Embodiment 1) The present invention will be described below based on the drawings showing a machine tool according to Embodiment 1. In the following description, the directions up, down, front, back, left, and right in the drawings 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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. The 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.

[0038] 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. The opening / closing detector 41c constitutes an opening / closing detection unit.

[0039] As shown in Figure 5, the second magazine 8 is covered by a cover 52. The cover 52 constitutes a regulating cover. 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.

[0040] When a tool is transported between the first magazine 6 and the second magazine 8, the tool passes through the opening 52a. The cover 52 makes it difficult for the operator to approach the arm 8b. The operator cannot attach or detach tools to or from the arm 8b. In other words, the cover 52 restricts the operator from attaching or detaching tools to or from the second magazine 8 without using the tool transport device.

[0041] 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).

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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 of the second magazine 7.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] If the piston 91 is 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.

[0073] 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.

[0074] 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 not a problem 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 not a problem 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.

[0075] 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.

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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, an operation panel 41b, and an open / close detector 41c. 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, an input / output interface (input / output I / F) 60d, and a timer 60e. 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] When an operator attaches tool 50 to arm 6b of the first magazine 6, the operator operates the control panel 41b to input the tool identification number of the attached tool 50 and the arm identification number of the 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 panel 41b to delete the tool identification number linked to the arm identification number of the arm 6b from which the tool 50 was removed.

[0090] 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.

[0091] 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.

[0092] 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.

[0093] 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. When the tool 50 is transported to the arm 6b that has the empty flag set at the first replacement position P1, the control unit 60a releases the empty flag. That is, the control unit 60a deletes the empty flag linked to the arm identification number of the arm 6b located at the first replacement position P1 from the auxiliary storage unit 60c.

[0094] 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.

[0095] When the tool 50 is removed from the arm 8b located at the second replacement 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 replacement position P2. When the tool 50 is transported to the arm 8b that has the empty flag set at the second replacement position P2, the control unit 60a releases the empty flag. That is, the control unit 60a deletes the empty flag linked to the arm identification number of the arm 8b located at the second replacement position P2 from the auxiliary storage unit 60c.

[0096] When the control unit 60a detects that the door 41a is open using the open / close detector 41c, it refers to the timer 60e and stores information indicating that the door has been opened in the main memory unit 60b or the auxiliary memory unit 60c, linked to the time the door was opened.

[0097] Figures 15 to 18 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 performs, for example, the movement of the pod 9f from the replacement position arm 6c to the replacement position arm 8d and the movement of the pod 9f from the replacement position arm 8d to the replacement position arm 6c as a single process. That is, in any case where the tool is moved from the replacement position arm 6c to the replacement position arm 8d and also from the replacement position arm 8d to the replacement position arm 6c, where the tool is moved only from the replacement position arm 6c to the replacement position arm 8d, and where the tool is moved only from the replacement position arm 8d to the replacement position arm 6c, the process of moving the pod 9f from the replacement position arm 6c to the replacement position arm 8d and the process of moving the pod 9f from the replacement position arm 8d to the replacement position arm 6c are executed. When moving a tool only from replacement position arm 6c to replacement position arm 8d, both replacement position arm 8d and replacement position arm 6c are made empty arms during the process of moving pod 9f from replacement position arm 8d to replacement position arm 6c. When moving a tool only from replacement position arm 8d to replacement position arm 6c, both replacement position arm 6c and replacement position arm 8d are made empty arms during the process of moving pod 9f from replacement position arm 6c to replacement position arm 8d. However, when moving a tool only from replacement position arm 6c to replacement position arm 8d, the process of moving pod 9f from replacement position arm 8d to replacement position arm 6c may be omitted, and when moving a tool only from replacement position arm 8d to replacement position arm 6c, the process of moving pod 9f from replacement position arm 6c to replacement position arm 8d may be omitted.

[0098] Initially, the pod 9f is located in the non-interference position P3. The control unit 60a positions the main spindle 10a at the origin (S1) and 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 control unit 60a opens the shutter of the opening 52a (S3) and 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 moves the pod 9f to the first replacement position P1 (S5). The control unit 60a switches the solenoid valve 63 to the first position, i.e., switches the pod 9f to the gripping state and detects the presence or absence of a tool (S6). In step S6, the control unit 60a detects the presence or absence of a tool on the arm 6b located at the first replacement 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 (S7).

[0099] 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.

[0100] 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 does not correspond to the presence or absence of the tool identification number. The control unit 60a determines that if the detection results of the first detection unit 61 and the second detection unit 62 indicate an idle 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 does not correspond to the presence or absence of the tool identification number.

[0101] If the detection results of the first detection unit 61 and the second detection unit 62 are determined to correspond to the presence or absence of a tool identification number (S7: YES), the control unit 60a determines whether the arm 6b at the first replacement position P1 is empty or not (S8). 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.

[0102] If it is determined that the arm 6b at the first swap position P1 is not empty (S8: NO), the control unit 60a moves the pod 9f to the second swap position P2 (S9) and switches the solenoid valve 63 to the second position, i.e., switches the pod 9f to the non-gripping state (S10). The control unit 60a then removes the empty flag set for the arm 8b at the second swap position P2 (S12) and moves the pod 9f to the non-interference position P3 (S13).

[0103] The control unit 60a sets an empty flag for the arm 6b at the first exchange position P1 (S14). If it is determined in step S8 that the arm 6b at the first exchange position P1 is empty (S8: YES), the pod 9f is moved to the non-interference position P3 (S11). The control unit 60a sets an empty flag for the arm 6b at the first exchange position P1 (S14). After processing in step S14, the control unit 60a drives the motor 8c to locate the arm 8b of the second magazine 8 specified in the transport command to the second exchange position P2 (S15). The control unit 60a moves the pod 9f to the second exchange position P2 (S16), switches the solenoid valve 63 to the first position, that is, switches the pod 9f to the gripping state, and detects the presence or absence of a tool (S17). 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 (S18).

[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 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.

[0105] If the detection results of the first detection unit 61 and the second detection unit 62 are determined to correspond to the presence or absence of a tool identification number (S18: YES), the control unit 60a determines whether the arm 8b at the second replacement position P2 is empty or not (S19). 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.

[0106] In step S19, if it is determined that the arm 8b at the second exchange position P2 is not empty (S19: NO), the control unit 60a moves the pod 9f to the first exchange position P1 (S20). The control unit 60a switches the solenoid valve 63 to the second position, i.e., switches the pod 9f to the non-gripping state (S21). The control unit 60a releases the empty flag set for the arm 6b at the first exchange position P1 (S22) and moves the pod 9f to the non-interference position P3 (S23). The control unit 60a determines whether or not there is a next transport command (S24).

[0107] In step S19, if it is determined that the arm 8b at the second swap position P2 is empty (S19: YES), the control unit 60a moves the pod 9f to the non-interference position P3 (S38) and determines whether or not there is a next transport command (S24).

[0108] In step S24, if it is determined that there is a next transport command (S24: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 (S24:NO), the control unit 60a closes the shutter (S25) and determines whether a tool to be mounted on the spindle 10a is specified in the transport command (S26). If it is determined that a tool to be mounted on the spindle 10a is not specified (S26:NO), the control unit 60a terminates the process. If it is determined that a tool to be mounted on the spindle 10a is specified (S26: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 (S27), lowers the spindle 10a (S28), and terminates the process.

[0109] In step S7, if the control unit 60a determines that 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, it stores information in the auxiliary storage unit 60c indicating that the arm 6b at the first replacement position P1 is a normal arm. In step S18, if the control unit 60a determines that 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, it stores information in the auxiliary storage unit 60c indicating that the arm 8b at the second replacement position P2 is a normal arm. The control unit 60a can execute the tool transport process multiple times. When the tool transport process is executed again, the information indicating that the arm is normal, which was stored in the previous tool transport process, is not erased from the auxiliary storage unit 60c.

[0110] In step S7, 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 (S7: NO), the control unit 60a determines whether the arm whose detection result does not correspond to the presence or absence of a tool identification number is an arm of the first magazine 6 (S29). Hereinafter, an arm whose detection result does not correspond to the presence or absence of a tool identification number will be referred to as an abnormal arm. Since a determination was made in step S7 regarding arm 6b of the first magazine 6, the control unit 60a determines that the abnormal arm is arm 6b of the first magazine 6 (S29: YES). As mentioned above, the operator cannot attach or detach tools to the arms of the second magazines 7 and 8. The operator can only attach and detach tools to the first magazine 6. If an abnormality occurs in the arms of the second magazines 7 and 8, there is a high possibility that a physical abnormality has occurred in the machine tool. Physical abnormalities include, for example, a tool falling off, or an arm not opening and the tool not being able to detach. If an abnormality occurs in arm 6b of the first magazine 6, there is a possibility that the abnormality is due to an error in the operator's information input. Operator errors in data entry include, for example, storing a tool identification number associated with an empty arm, or not storing a tool identification number associated with an arm that holds a tool.

[0111] The control unit 60a determines whether or not the arm was determined to be normal in the previous tool transport process (S30). If, in step S30, it is determined that the arm was not determined to be normal in the previous tool transport process (S30: NO), that is, if there is a possibility that an abnormality has occurred due to an error in the operator's information input, the control unit 60a switches the solenoid valve 63 to the second position, that is, switches the pod 9f to the non-gripping state (S31). The control unit 60a moves the pod 9f to the non-interference position P3 (S32), switches the solenoid valve 63 to the first position, that is, switches the pod 9f to the gripping state (S33), closes the shutter (S34), rotates the first magazine 6 to position the abnormal arm where the tool is mounted on the spindle 10a, that is, the spindle mounting position which is the lowest position of the first magazine 6 (S35), outputs a signal to the notification unit 64 to notify of the abnormality (S36), and ends the process.

[0112] The notification unit 64 performs actions such as opening the opening / closing door 41a to prompt the operator to check the abnormal arm, displaying information such as that transport processing is not possible, that the machine tool is stopped, or that a tool may have fallen off the pod 9f, or illuminating or flashing a light, or emitting a sound. The operator can recognize the abnormality through the notification from the notification unit 64. The operator can, for example, operate the control panel 41b to open the opening / closing door 41a. The operator can, for example, remove a tool if one is attached to an abnormal arm that should be empty, or attach a tool to an abnormal arm that should have a tool attached but is empty. In other words, the operator can return the abnormal arm to a normal arm.

[0113] In step S30, if it is determined that the arm was normal in the previous tool transport process (S30: YES), the control unit 60a does not perform the processes in steps S31 to S35, stops the movement of the pod 9f (S37), and proceeds to step S36. If the arm that was previously determined to be normal is now determined to be an abnormal arm, an abnormality has occurred in arm 6b even though the operator has not attached or removed a tool from the first magazine 6. Therefore, the abnormality in arm 6b of the first magazine 6 is highly likely to be due to a physical abnormality in the machine tool. For this reason, the pod 9f is stopped immediately without performing the processes in steps S31 to S35, that is, without performing the process of automatically moving the pod 9f to a non-interference position.

[0114] In step S18, if the control unit 60a determines that 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 (S18: NO), the control unit 60a proceeds to step S29. Since the arms of the second magazines 7 and 8 were determined in step S18, the control unit 60a determines that the abnormal arm is not the arm 6b of the first magazine 6 (S29: NO). That is, it determines that an abnormality has occurred in the arms of the second magazines 7 and 8. The control unit 60a proceeds to step S37. As mentioned above, if an abnormality has occurred in the arms of the second magazines 7 and 8, there is a high possibility that a physical abnormality has occurred in the machine tool. Therefore, the pod 9f is stopped immediately without performing the process of automatically moving the pod 9f to a non-interference position. The processing in steps S5 and S16 by the control unit 60a constitutes the first movement process, the processing in steps S6 and S17 constitutes the detection process, and the processing in steps S7 and S18 constitutes the determination process. The processing in step S32 by the control unit 60a constitutes the second movement process.

[0115] In the machine tool according to Embodiment 1, if there is a possibility that an abnormality has occurred due to an error in the operator's information input, the pod 9f is automatically moved to a non-interfering position, and if there is a high possibility that a physical abnormality has occurred in the machine tool, the movement of the pod 9f is immediately stopped.

[0116] Furthermore, 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, it is determined that there is an abnormality in the arm. If an abnormality is determined to be in the arm, the abnormality is reported. The operator can also check the abnormal arm by placing it in the spindle mounting position where the tool can be attached and detached. Note that the position where the tool can be attached and detached is not limited to the spindle mounting position. The abnormal arm may be placed in a position other than the spindle mounting position where the tool can be attached and detached. Furthermore, if an abnormality occurs in the second magazines 7 and 8, i.e., magazines where the operator does not normally attach or detach tools, it is highly likely that there is a physical abnormality in the machine tool, so the movement of the pod 9f is stopped. Furthermore, if the pod 9f is to be automatically moved to a non-interference position after an abnormality occurs, the pod 9f is moved without gripping a tool.

[0117] (Embodiment 2) The present invention will be described below based on drawings showing a machine tool according to Embodiment 2. Figure 19 is a flowchart illustrating the tool transport process by the control unit 60a. The control unit 60a of the machine tool according to Embodiment 2 executes the processes in steps S1 to S39. The processes in steps S1 to S38 in Embodiment 2 are the same as those in Embodiment 1, so a detailed explanation will be omitted. The process in step S39 will now be described.

[0118] In step S30, if it is determined that the arm was normal in the previous tool transport process (S30: YES), the control unit 60a determines whether the opening / closing door 41a opened between the current tool transport process and the previous tool transport process (S39). If it is determined that the opening / closing door 41a did not open (S39: NO), the process proceeds to step S37, and the pod 9f is stopped. That is, the pod 9f stops without moving to a non-interference position. If it is determined that the opening / closing door 41a is open (S39: YES), the control unit 60a executes the processes in steps S31 to S36. That is, the pod 9f automatically moves to a non-interference position.

[0119] When the opening / closing door 41a is opened, the operator can attach or detach a tool to the arm 6b and update the arm identification number and tool identification number. In other words, there is a risk of information input errors by the operator. Therefore, if the opening / closing door 41a is opened between the current tool transport process and the previous tool transport process, and an abnormality occurs in the arm 6b during the current tool transport process, the control unit 60a automatically moves the pod 9f to a non-interference position. In the machine tool according to Embodiment 2, if there is a high possibility that a physical abnormality has occurred in the machine tool, the movement of the pod 9f is stopped, and if there is a high possibility that the abnormality is due to an information input error by the operator, the pod 9f is moved to a non-interference position.

[0120] Furthermore, the operator may be able to attach and detach tools to the arms of the second magazines 7 and 8. In this case, step S29 may be omitted and the tool transport process in Embodiment 1 or 2 may be executed. That is, if an arm of the second magazines 7 or 8 is an abnormal arm, the processes in steps S30 to S39 may be executed for this abnormal arm.

[0121] Computer programs (program products) can be deployed to run on a single computer, located in one site, or distributed across multiple sites and interconnected by a communication network.

[0122] 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]

[0123] 6 First Magazine 6b Arm 7 Second Magazine 8 Second Magazine 8b Arm 9. Tool conveying device 9f Pod 10. Spindle head 41a Opening and closing door 41b Control panel 41c Open / Close Detector 52 Cover 52a aperture 60 Control device 60a Control Unit 60b Main memory 60c Auxiliary storage unit 60c Auxiliary storage unit 60d Input / Output Interface 60e timer 61 First detection unit 62 Second detection unit 63 Solenoid valve 64 Hochi Department 65 Storage medium

Claims

1. A first magazine having multiple first storage compartments for storing tools, A second magazine having multiple second storage compartments for storing tools, A tool transport device having a tool gripping portion that can move 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, which does not interfere with the first and second magazines. A detection unit that detects the presence or absence of a tool based on the gripping state of the gripping part, A control device for controlling a machine tool, including, 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 movement process is performed on the tool transport device to move the gripping portion to the first replacement position or the second replacement position, After the execution of the first movement process, the detection unit performs a detection process to detect whether a tool is present in the first storage unit at the first replacement position, or whether a tool is present in the second storage unit at the second replacement position. A determination process to determine whether or not there is an abnormality in the first storage unit or the second storage unit based on the detection result of the detection process, If an abnormality is determined in the determination process, a second movement process is performed on the tool transport device to move the gripping part from the first or second replacement position to the non-interference position. A control device that performs this operation.

2. The system includes a storage unit that stores information indicating the presence or absence of tools in the plurality of first storage compartments and information indicating the presence or absence of tools in the plurality of second storage compartments. In the determination process, if the presence or absence of a tool in the first storage unit detected in the detection process does not match the presence or absence of a tool in the first storage unit stored in the storage unit, or if the presence or absence of a tool in the second storage unit detected in the detection process does not match the presence or absence of a tool in the second storage unit stored in the storage unit, it is determined that there is an abnormality. The control device according to claim 1.

3. If the aforementioned determination process determines that an abnormality exists, a signal indicating the abnormality is output. The control device according to claim 1 or 2.

4. After the execution of the second movement process, the first magazine or the second magazine is driven so that the first or second storage unit, which was determined to have an abnormality, is positioned in a location where a tool can be attached to or detached. The control device according to claim 1 or 2.

5. If the first storage unit or the second storage unit is determined to be free of abnormalities in the determination process, the first movement process, the detection process, and the determination process are executed again, and if it is determined that there is an abnormality, the movement operation of the gripping unit is stopped. The control device according to claim 1 or 2.

6. The machine tool includes a cover that covers the first magazine and the second magazine, an opening / closing door attached to the cover, and an opening / closing detection unit that detects the opening and closing of the opening / closing door. If, in the determination process, the first movement process, the detection process, and the determination process are executed again on the first storage unit or the second storage unit which was determined to be free of abnormalities, then, If the opening / closing detection unit does not detect that the door is open during the two determination processes, the movement of the gripping unit is stopped. If the opening / closing detection unit detects that the door is open during the two determination processes, the second movement process is executed. The control device according to claim 1 or 2.

7. The first magazine can be manually attached to and detached from it. The tool transport device is not used and the tool is restricted by a restricting cover that restricts the attachment and removal of the tool to and from the second magazine. In the first movement process, the gripping part is moved to the second replacement position relative to the tool transport device; in the detection process, the presence or absence of a tool in the second storage unit at the second replacement position is detected; in the determination process, based on the detection result of the detection process, it is determined whether or not there is an abnormality in the second storage unit; and if an abnormality is determined in the determination process, the gripping part is stopped. The control device according to claim 1 or 2.

8. In the second movement process, after releasing the gripping operation of the tool by the gripping part, the gripping part is moved to the non-interference position. The control device according to claim 1 or 2.

9. A first magazine having multiple first storage compartments for storing tools, A second magazine having multiple second storage compartments for storing tools, A tool transport device having a tool gripping portion that can move 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, which does not interfere with the first and second magazines. A detection unit that detects the presence or absence of a tool based on the gripping state of the gripping part, Equipped with a control device, 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, A first movement process is performed on the tool transport device to move the gripping portion to the first replacement position or the second replacement position, After the execution of the first movement process, the detection unit performs a detection process to detect whether a tool is present in the first storage unit at the first replacement position, or whether a tool is present in the second storage unit at the second replacement position. A determination process to determine whether or not there is an abnormality in the first storage unit or the second storage unit based on the detection result of the detection process, If an abnormality is determined in the determination process, a second movement process is performed on the tool transport device to move the gripping part from the first or second replacement position to the non-interference position. A machine tool that performs this task.

10. A control method for controlling 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 moving a gripping part that grips 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 that detects 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, The tool transport device is subjected to the movement of the gripping portion to the first replacement position or the second replacement position. The detection unit detects whether a tool is present in the first storage compartment at the first replacement position, or whether a tool is present in the second storage compartment at the second replacement position. Based on the detection results, it is determined whether or not there is an abnormality in the first storage unit or the second storage unit. If an abnormality is detected, the tool transport device will perform a movement of the gripping portion from the first or second replacement position to the non-interference position. Control method.

11. A computer program executable on a control device that controls 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 moving a gripping part that grips 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, which does not interfere with the first and second magazines; and a detection unit that detects 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, The tool transport device is subjected to the movement of the gripping portion to the first replacement position or the second replacement position. The detection unit detects whether a tool is present in the first storage compartment at the first replacement position, or whether a tool is present in the second storage compartment at the second replacement position. Based on the detection results, it is determined whether or not there is an abnormality in the first storage unit or the second storage unit. If an abnormality is detected, the tool transport device will perform a movement of the gripping portion from the first or second replacement position to the non-interference position. A computer program that executes a process.

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