Control device

Abstract

To provide a control device that enables a user to easily grasp the fact that machining time of a machining tool has increased by executing retry processing.SOLUTION: A control device performs attachment operation using a tool changer. After performing the attachment operation, the control device determines whether an attachment state is a foreign matter adhesion state. When determining that the attachment state is the foreign matter adhesion state, the control device executes retry processing. The control device executes storing processing for storing retry information in a storing device and display processing for displaying, on a display device 38, an alarm history image, a cycle-time history image and a used-tool history image 330.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present invention relates to a control device. [Background technology]

[0002] Numerical control devices that determine the mounting state when a tool is mounted on the spindle of a machine tool are known. The numerical control device described in Patent Document 1 mounts a tool on the spindle by moving an attachment mechanism in the Z-axis direction. At this time, the numerical control device acquires the torque of the Z-axis motor that moves the attachment mechanism in a time series. The numerical control device derives a differential value of the torque and stores the differential value in association with the position of the attachment mechanism in the Z-axis direction. The numerical control device determines and stores the peak position from the fluctuation of the differential value. The numerical control device determines the mounting state based on statistical values ​​obtained by statistically processing the peak positions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-56673 Summary of the Invention [Problem to be solved by the invention]

[0004] The mounting state includes a foreign matter adhesion state in which the tool is mounted on the spindle with foreign matter adhering between the spindle and the tool. If the mounting state is determined to be a foreign matter adhesion state, the numerical control device may execute a retry operation to detach and reattach the tool to resolve the foreign matter adhesion state. In this case, the machining time of the machine tool increases by the time required for the retry operation. In this case, the user may not be aware that the retry operation has increased the machining time of the machine tool.

[0005] An object of the present invention is to provide a control device that allows a user to easily understand that the machining time of a machine tool has increased due to the execution of a retry process. [Means for solving the problem]

[0006] A control device according to the present invention is a control device for controlling a machine tool including a spindle on which a tool is attached, and a tool changer that loads the tool and changes the tool attached to the spindle, and is characterized by executing: a mounting process in which the tool changer executes an operation to mount the tool on the spindle; a determination process in which, during the mounting operation by the mounting process, a foreign matter adhered state is determined in which the tool is mounted on the spindle with foreign matter adhering between the spindle and the tool; a retry process in which, if the determination process determines that the foreign matter adheres, the tool changer executes an operation to detach and mount the tool, and then determines whether the foreign matter adheres; and post-processing including at least one of a storage process in which, if the retry process has been executed, retry information indicating that the retry process has been executed, or a notification process in which the retry information is notified.

[0007] According to this, when a retry process is executed, the control device executes at least one of a storage process or a notification process. By checking the retry information stored by the storage process or the retry information notified by the notification process, the user can understand that the retry process has been executed. Therefore, the control device allows the user to easily understand that the execution of the retry process by the machine tool has increased the machining time.

[0008] The control device of the present invention may, when the retry process is executed, execute at least the notification process in the post-processing, and the notification process may notify the retry information by a notification device. In this way, the user can know that the retry process has been executed by checking the retry information notified by the notification device. Therefore, the user can easily know that the processing time has increased due to the execution of the retry process by the control device.

[0009] In the present invention, the notification device may include a display device that displays an image, and the notification process may include displaying a retry image indicating the retry information on the display device. This allows the user to understand that the retry process has been executed by checking the retry image displayed by the display device. Therefore, even when the control device notifies using an image, the user can easily understand that the processing time has increased due to the execution of the retry process.

[0010] In the present invention, the notification process may display the time when the retry process was performed as the retry information. In this way, the user can know the time when the retry process was performed by checking the retry image displayed on the display device. Therefore, by the control device displaying the time when the retry process was performed, the user can easily know the time when the processing time increased.

[0011] In the present invention, the notification process may display, as the retry information, tool information of the tool that has been the target of the detachment operation and the attachment operation in the retry process, whereby a user can easily recognize the tool that has been the target of the detachment operation and the attachment operation from the tool information by checking the retry image displayed on the display device.

[0012] In the present invention, the notification process may display, as the tool information, a tool number assigned to identify the tool that was the target of the detachment operation and the attachment operation in the retry process. This allows the user to easily identify the tool that was the target of the detachment operation and the attachment operation by checking the tool number on the retry image. Therefore, the control device allows the user to easily identify the tool number of the tool that was the target of the retry process.

[0013] In the present invention, the notification process may display, as the tool information, the number of times the retry process has been executed for each tool during execution of a machining program for machining a workpiece by the machine tool. In this way, by checking the number of times the retry process has been executed for each tool in the retry image, it is possible to easily grasp the frequency at which the retry process is executed for each tool.

[0014] In the present invention, the notification process may display, as the retry information, the total number of retry processes executed during execution of the machining program for machining the workpiece by the machine tool. By checking the total number of retry processes in the retry image, the user can easily understand the frequency with which retry processes in the machining program are executed.

[0015] The control device of the present invention may execute the storage process and the notification process in the post-processing when the retry process is executed, the storage process may store the retry information in a storage device, and the notification process may display the retry image indicating a history of the retry information stored in the storage device on the display device. In this way, by checking the retry process history of the retry image, a user can easily grasp the tendency of retry processes to be executed in the machining program.

[0016] In the present invention, the notification device may include an output device that outputs a signal for communication, and the notification process may include outputting a retry signal indicating the retry information from the output device. In this way, a user can know that the retry process has been executed by checking the retry signal output from the output device on an external device that has received the retry signal.

[0017] The control device of the present invention may further execute a cleaning process to clean at least one of the tool and the spindle using a cleaning device between the detachment operation and the attachment operation in the retry process. In this way, the control device eliminates the foreign matter adhesion state through the cleaning process. Therefore, the control device can suppress an increase in machining time due to repeated execution of the retry process. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a perspective view of a machine tool 1. [Figure 2] FIG. 2 is a right side view of the spindle head 7 and its surroundings. [Figure 3] FIG. 2 is a vertical cross-sectional view of the spindle head 7 and its surroundings. [Figure 4] FIG. 2 is a vertical cross-sectional view of the main shaft 9. [Figure 5] FIG. [Figure 6] FIG. 10 is an enlarged view of the spindle head 7 and its surroundings when cleaning an object. [Figure 7] FIG. 10 is a right side view of the spindle head 7 and its surroundings when cleaning an object. [Figure 8] FIG. 1 is a circuit diagram showing a cleaning device 100. [Figure 9] 2 is a block diagram showing the electrical configuration of the machine tool 1 and the control device 30. FIG. [Figure 10] 10 is a graph showing a disturbance force F and a differential value f that vary depending on the Z-axis position. [Figure 11] FIG. 3 is a diagram showing an alarm history image 310. [Figure 12] FIG. 3 is a diagram showing a cycle time history image 320. [Figure 13] FIG. 10 is a diagram showing a tool usage history image 330. [Figure 14] 10 is a flowchart of a main process. [Figure 15] 15 is a flowchart showing a continuation of FIG. 14. [Figure 16] 16 is a flowchart continuing from FIG. 15. DETAILED DESCRIPTION OF THE INVENTION

[0019] An embodiment of the present invention will be described with reference to the drawings. In the following description, left / right, front / rear, and up / down directions will be used as indicated by arrows in the drawings. The left / right, front / rear, and up / down directions of the machine tool 1 correspond to the X-axis, Y-axis, and Z-axis directions of the machine tool 1, respectively. The rightward, forward, and upward directions are positive directions, and the leftward, backward, and downward directions are negative directions. The machine tool 1 shown in FIG. 1 is a machine that performs cutting on a workpiece (not shown) using a tool T. A control device 30 is a machine that controls the operation of the machine tool 1. In this embodiment, "ATC" is an abbreviation for "Automatic Tool Changer." Furthermore, in this embodiment, "NC" is an abbreviation for "Numerical Control."

[0020] <Structure of machine tool 1> As shown in Figures 1 and 2, the machine tool 1 has a base 2, a column 5, a control box 6, a table device 10, a spindle head 7, a spindle 9, a tool changer 20, and a cleaning device 100. The base 2 is a metal base having a substantially rectangular parallelepiped shape. The column 5 is fixed to the rear portion of the upper surface of the base 2. The column 5 is a vertically extending pillar. The control box 6 is fixed to the back surface of the column 5. The control box 6 houses the control device 30. Support plates 78a and 78b are provided on the upper part of the column 5. The support plate 78a is a plate extending forward from the right front end of the upper part of the column 5. The support plate 78b is a plate extending forward from the left front end of the upper part of the column 5. The support plates 78a and 78b support the tool changer 20 and the cleaning device 100, which will be described later.

[0021] The table device 10 has a Y-axis movement mechanism (not shown), a Y-axis table 12, a table 13, and an X-axis movement mechanism (not shown). The Y-axis movement mechanism is provided on the upper surface of the base 2 and in front of the column 5, and has a Y-axis motor 54 (see FIG. 9). The Y-axis movement mechanism moves the Y-axis table 12 in the Y-axis direction in response to driving of the Y-axis motor 54. The X-axis movement mechanism is provided above the Y-axis table 12, and has an X-axis motor 53 (see FIG. 9). The X-axis movement mechanism moves the table 13 in the X-axis direction in response to driving of the X-axis motor 53. Therefore, the table 13 can be moved in the X-axis and Y-axis directions above the base 2 by the X-axis movement mechanism and the Y-axis movement mechanism.

[0022] <Structure of the Z-axis movement mechanism 8> As shown in Fig. 3, a Z-axis movement mechanism 8 is provided at the front part of the column 5. The Z-axis movement mechanism 8 includes a ball screw 41, bearing parts 42 and 43, a cam follower 49, and a Z-axis motor 51 (see Fig. 9). The ball screw 41 is provided at the front part of the column 5 and extends in the Z-axis direction. The bearing parts 42 and 43 are inserted through the ball screw 41 and support the ball screw 41 rotatably. The bearing part 42 is provided above the bearing part 43. The cam follower 49 is provided at the front end of the bearing part 42. The cam follower 49 slides on the cam surface of the plate cam 47 of the spindle head 7 described later.

[0023] The Z-axis motor 51 is fixed above the bearing part 42. The ball screw 41 is connected to the output shaft of the Z-axis motor 51 via a coupling (not shown). The ball screw 41 is rotated forward and backward around an axis extending in the vertical direction by the drive of the Z-axis motor 51. A nut 44 is screwed between the bearing parts 42 and 43 on the ball screw 41. The nut 44 is fixed to the rear end part of the spindle head 7. When the Z-axis motor 51 rotates in the forward direction, the ball screw 41 rotates, and the nut 44 and the spindle head 7 rise integrally. When the Z-axis motor 51 rotates in the reverse direction, the ball screw 41 rotates in the reverse direction, and the nut 44 and the spindle head 7 descend integrally.

[0024] <Internal structure of the spindle head 7> As shown in Figs. 2 and 3, the spindle head 7 is provided at the front part of the column 5. The spindle head 7 has a box shape. When the spindle head 7 moves up and down by the drive of the Z-axis motor 51, it passes between the support plate 7a and the support plate 7b in the left-right direction. The spindle head 7 includes a spindle motor 52, a crank lever 45, a support shaft 46, and a coil spring 48. The spindle motor 52 is fixed to the front part of the upper surface of the spindle head 7. A communication hole 56 (see Fig. 8) is formed in the spindle motor 52. The communication hole 56 opens in the vertical direction through the spindle motor 52.

[0025] <当 The spindle 46 is fixed to the inside of the rear part of the spindle head 7. The spindle 46 is rod-shaped and extends in the left-right direction. The crank lever 45 is provided on the top of the spindle head 7. The crank lever 45 has levers 45a and 45b. The lever 45a extends substantially in the front-rear direction. The lever 45b extends substantially upward from the rear end of the lever 45a. The spindle 46, which extends in the left-right direction, is inserted into the connection between the levers 45a and 45b. The crank lever 45 can swing around the spindle 46. A plate cam 47 is provided at the rear end of the lever 45b. A cam surface is formed on the back surface of the plate cam 47. The cam surface of the plate cam 47 can come into contact with and separate from the cam follower 49. The coil spring 48 is provided on the inside of the rear part of the spindle head 7. The coil spring 48 extends in the front-rear direction. One end of the coil spring 48 is fixed to the back surface of the spindle head 7. The rear end of the coil spring 48 is fixed to the rear end of the crank lever 45 below the plate cam 47. The coil spring 48 constantly biases the crank lever 45 clockwise when viewed from the right side.

[0026] <Internal structure of spindle 9> As shown in Figures 3 and 4, the spindle 9 is provided inside the lower front part of the spindle head 7 and has a cylindrical shape extending in the vertical direction. The spindle 9 is rotatably supported by the spindle head 7. The spindle 9 is connected to the output shaft of a spindle motor 52. Driven by the spindle motor 52, the spindle 9 is rotated forward and backward around the axis extending in the vertical direction.

[0027] The main shaft 9 has a shaft hole 91, a mounting hole 92, a space 93, a slide hole 94, a clamp shaft 81, and a spring 82. The shaft hole 91 is formed from the upper end to the lower end of the main shaft 9 and passes through the center of the main shaft 9. The shaft hole 91 is connected to the communication hole 56 of the main shaft motor 52.

[0028] The mounting hole 92 opens to the bottom surface (hereinafter referred to as the lower surface 96) below the spindle 9. The mounting hole 92 passes through the center of the spindle 9. A tool T, which will be described later, is mounted on an inner surface 92a of the mounting hole 92. A space 93 is formed above the mounting hole 92. The space 93 is connected to the mounting hole 92. The sliding hole 94 is formed between the axial hole 91 and the space 93 in the vertical direction. The sliding hole 94 connects the axial hole 91 and the space 93. In other words, the mounting hole 92 communicates with the communicating hole 56 (see FIG. 8) via the space 93, the sliding hole 94, and the axial hole 91.

[0029] The clamp shaft 81 is provided inside the shaft hole 91 and is movable up and down relative to the shaft hole 91. The clamp shaft 81 has a support portion 83, a shaft portion 84, and a grip portion 85. The support portion 83 is provided at the upper end of the clamp shaft 81 and is columnar. The support portion 83 supports a pin 95. The pin 95 is provided to protrude from the clamp shaft 81. The pin 95 protrudes outside the main shaft 9 through a through hole (not shown) that penetrates the main shaft 9 in the front-to-rear direction. The pin 95 is located below the lever 45a. When the crank lever 45 swings, the front end of the lever 45a moves toward and away from the pin 95.

[0030] The shaft portion 84 is columnar and extends downward from the support portion 83. The grip portion 85 is provided at the lower end of the shaft portion 84 and has a plurality of steel balls (not shown). The spring 82 is inserted into the shaft hole 91. The upper end of the spring 82 engages with the support portion 83. The spring 82 constantly urges the clamp shaft 81 upward.

[0031] <Structure of Tool T> The structure of tool T will be explained using arrows in Figure 5 indicating left and right, front and rear, and up and down. Tool T has a holder 14 and a cutting tool 4. The cutting tool 4 is, for example, a drill, a tap, an end mill, a milling cutter, etc. The holder 14 has a flange 15, a shank 16, and a pull stud 17.

[0032] The flange 15 is cylindrical with an axis extending in the vertical direction. The lower end of the flange 15 holds the cutting tool 4. The flange 15 is detachably held by a grip arm 23 (described later). The shank 16 extends upward from the upper bottom surface of the flange 15. The shank 16 is conical, with a diameter that decreases upward. In a plan view, the diameter of the lower end of the shank 16 is smaller than the diameter of the upper bottom surface of the flange 15. Hereinafter, the surface of the upper bottom surface of the flange 15 to which the shank 16 is not connected will be referred to as the upper surface 15a. The upper surface 15a corresponds to the lower surface 96 of the spindle 9.

[0033] The shank 16 has a tapered surface 16a that corresponds to the inner surface 92a of the mounting hole 92. The pull stud 17 protrudes upward from the upper end of the shank 16. The pull stud 17 is T-shaped in side view. The pull stud 17 is gripped by multiple steel balls of the gripping portion 85 of the spindle 9. At this time, the lower surface 96 and the upper surface 15a come into surface contact, and the inner surface 92a and the upper surface 15a come into surface contact. When the pull stud 17 is gripped by the gripping portion 85 and the lower surface 96 and the upper surface 15a come into surface contact, and the inner surface 92a and the upper surface 15a come into surface contact, this is referred to as the tool T being mounted on the spindle 9 (see FIG. 4). Therefore, the spindle 9 has a two-face constraint configuration in which the inner surface 92a and the lower surface 96 restrict the position of the tool T.

[0034] <Structure of tool changer 20> 1 to 3, the tool changer 20 is provided at the front ends of the support plates 78a, 78b. The tool changer 20 is located in front of the spindle head 7 in the front-rear direction. The tool changer 20 is, for example, a turret-type tool changer that can carry a plurality of tools T.

[0035] The tool changer 20 has a tool magazine 21 and a magazine motor 55. The tool magazine 21 has a magazine body 22, a support shaft 25, and multiple grip arms 23. The magazine body 22 is approximately disk-shaped. The support shaft 25 is rod-shaped and extends downward and forward. The support shaft 25 is rotatable around its axis and supports the magazine body 22. The grip arms 23 are provided at predetermined intervals on the outer periphery of the magazine body 22. The grip arms 23 are provided so as to be swingable in the front-to-rear direction of the magazine body 22. The tip of the grip arm 23 detachably grips the flange 15 of the tool T. The output shaft of the magazine motor 55 is connected to the support shaft 25. The tool magazine 21 is rotated forward and backward around the axis of the support shaft 25 by the drive of the magazine motor 55.

[0036] <Attaching, detaching, and replacing tool T> 3 and 4, with tool T attached to spindle 9, Z-axis motor 51 rotates in the forward direction based on a control command from control device 30. Ball screw 41 rotates around its axis, and spindle head 7 and spindle 9 rise from the machining origin of table 13. The machining origin is the machine origin and is the highest position at which a workpiece can be machined.

[0037] When the spindle head 7 and spindle 9 rise, the cam follower 49 comes into contact with the plate cam 47 of the crank lever 45 and slides on the cam surface of the plate cam 47. The crank lever 45 rotates counterclockwise around the support shaft 46 as viewed from the right side, resisting the elastic force of the coil spring 48. The front end of the lever 45a engages with the pin 95 from above and presses the clamp shaft 81 downward. The clamp shaft 81 urges the gripping portion 85 downward against the elastic force of the spring 82. The gripping portion 85 releases its grip on the pull stud 17.

[0038] The spindle 9 further rises to the ATC origin. The ATC origin is the position of the spindle 9 and is located above the machining origin. When the spindle 9 is located at the ATC origin, the tool magazine 21 is rotatable.

[0039] When the spindle 9 rises, the lower surface 96 moves away from the upper surface 15a of the tool T. The inner surface 92a moves away from the tapered surface 16a of the tool T. The tool T is detached from the spindle 9. The tool T detached from the spindle 9 is referred to as the first tool. Of the multiple grip arms 23 in the tool changer 20, one grip arm 23 (hereinafter referred to as the first grip arm) at the tool change position grips the flange 15 of the first tool detached from the spindle 9. The tool change position is the lowest position of the tool magazine 21 and is a position that faces the spindle 9 in close proximity. Note that in FIG. 3, the tool T gripped by the grip arm 23 at the tool change position is omitted.

[0040] When the spindle head 7 reaches the ATC origin, the tool changer 20 rotates the tool magazine 21 by driving the magazine motor 55 based on a control command from the control device 30. The tool changer 20 indexes the tool T (hereinafter referred to as the second tool) specified by the control command to the tool change position. At this time, the tool magazine 21 rotates from a state in which the first tool is at the tool change position to a state in which the second tool is at the tool change position. The tool magazine 21 rotates with the first tool held by the first grip arm and the second tool held by another grip arm 23 (hereinafter referred to as the second grip arm). The second tool indexed to the tool change position is located below the spindle head 7 which has moved to the ATC origin.

[0041] Next, based on a control command from the control device 30, the Z-axis motor 51 rotates in the reverse direction. The ball screw 41 rotates in the reverse direction around its axis, and the spindle 9 descends from the ATC origin. The shank 16 of the second tool enters the mounting hole 92, and the pull stud 17 enters the space 93.

[0042] With the shank 16 inserted into the mounting hole 92, the spindle 9 and spindle head 7 continue to descend. The cam follower 49 slides along the cam surface of the plate cam 47 and then separates from the plate cam 47. The crank lever 45 rotates clockwise around the support shaft 46 as viewed from the right side due to the elastic force of the coil spring 48. The front end of the lever 45a moves upward away from the pin 95, releasing the downward pressure on the clamp shaft 81. The clamp shaft 81 releases the downward bias of the gripping portion 85.

[0043] The gripping portion 85 moves from the space 93 to the sliding hole 94. The gripping portion 85 grips the pull stud 17 of the second tool with multiple steel balls and pulls it up. The second grip arm releases its grip on the flange 15 of the second tool. The lower surface 96 comes into surface contact with the upper surface 15a of the tool T. The inner surface 92a comes into surface contact with the tapered surface 16a of the tool T. The spindle 9 completes the attachment of the second tool. The operation of the clamp shaft 81 and the crank lever 45 when the tool T is attached to the spindle 9 is referred to as the attachment operation. The operation of the clamp shaft 81 and the crank lever 45 when the tool T is detached from the spindle 9 is referred to as the detachment operation.

[0044] <Cleaning device 100> As shown in Figures 1, 2, and 6 to 8, the cleaning device 100 is provided on the column 5, support plates 78a and 78b, and spindle head 7. The cleaning device 100 cleans foreign matter adhering to the tool T and spindle 9 (hereinafter referred to as the target object) with a cleaning liquid. In this embodiment, the cleaning liquid is a coolant liquid. The cleaning device 100 has a first cleaning mechanism 110, a second cleaning mechanism 120, and a third cleaning mechanism 130.

[0045] The first cleaning mechanism 110 includes an air supply source 150 , flow paths 151 , 152 , 153 , and 154 , an electromagnetic valve 171 , a valve 111 , a pump 191 , and a tank 181 .

[0046] Air supply source 150 is capable of supplying air. Air supply source 150 is, for example, a compressor. Flow path 151 connects air supply source 150 and electromagnetic valve 171. Electromagnetic valve 171 is provided at one end of flow path 152. Electromagnetic valve 171 opens flow path 152 when in an excited state, and closes flow path 152 when in a non-excited state.

[0047] A valve 111 is provided at the other end of the flow path 152. The valve 111 is provided at one end of the flow path 153. The valve 111 is a mechanical valve that can open the flow path 153. When the electromagnetic valve 171 is in an excited state and air is supplied from the air supply source 150 to the flow path 152, the valve 111 opens the flow path 153. When the electromagnetic valve 171 is in a non-excited state and air is not supplied from the air supply source 150 to the flow path 152, the valve 111 closes the flow path 153.

[0048] The other end of flow path 153 is connected to the upper end of communication hole 56. One end of flow path 154 is connected to valve 111. The other end of flow path 154 is connected to pump 191. Pump 191 is housed in tank 181. Tank 181 is provided above column 5 and stores the cleaning liquid. When valve 111 opens flow path 153, pump 191 supplies the cleaning liquid stored in tank 181 to communication hole 56.

[0049] The cleaning liquid supplied to the communication hole 56 is sprayed as a jet of water a (see FIGS. 6 and 8) toward the inner surface 92a of the mounting hole 92 through the shaft hole 91, the sliding hole 94, and the space 93. The jet of water a cleans the inner surface 92a.

[0050] The second cleaning mechanism 120 includes an air supply source 160 , flow paths 212 , 222 , 105 , 106 , and 101 , an electromagnetic valve 172 , a valve 103 , branch paths 102 and 104 , nozzles 131 and 132 , a pump 191 , and a tank 181 .

[0051] The air supply source 160 is capable of supplying air. The air supply source 160 is, for example, a compressor. The flow path 212 connects the air supply source 160 and an electromagnetic valve 172. The electromagnetic valve 172 is provided at one end of a flow path 222. The electromagnetic valve 172 opens the flow path 222 when in an excited state, and closes the flow path 222 when in a non-excited state.

[0052] A valve 103 is provided at the other end of the flow path 222. The valve 103 is connected to a branch path 104. The valve 103 is a mechanical valve that can open the branch path 104. When the electromagnetic valve 172 is in an excited state and air is supplied from the air supply source 160 to the flow path 222, the valve 103 opens the branch path 104. When the electromagnetic valve 172 is in a non-excited state and air is not supplied from the air supply source 160 to the flow path 222, the valve 103 closes the branch path 104.

[0053] One of the paths branched by branch path 104 is connected to one end of flow path 105. The other end of flow path 105 is connected to nozzle 131 (see FIG. 2). Nozzle 131 is provided on support plate 78a, and a nozzle hole (not shown) is formed that opens obliquely downward toward the tool change position. The other of the paths branched by branch path 104 is connected to one end of flow path 106. The other end of flow path 106 is connected to nozzle 132 (see FIG. 1). Nozzle 132 is provided on support plate 78b, and a nozzle hole (not shown) is formed that opens obliquely downward toward the tool change position.

[0054] One end of the flow path 101 is connected to a pump 192. The pump 192 is housed in a tank 182. The tank 182 is provided above the column 5 and stores the cleaning liquid. The other end of the flow path 101 is connected to a branch path 102. One of the paths branched by the branch path 102 is connected to a valve 103. The other path branched by the branch path 102 is connected to a flow path 107, which will be described later. When the valve 103 opens the branch path 104, the pump 192 supplies the cleaning liquid stored in the tank 181 to the nozzles 131 and 132.

[0055] The nozzles 131, 132 supplied with the cleaning liquid spray a jet stream b (see FIGS. 7 and 8) obliquely downward from the nozzle holes. The jet stream b cleans the upper surface 15a and tapered surface 16a of the tool T positioned at the tool replacement position. Note that the jet stream b sprayed from the nozzle 132 is not shown in FIG.

[0056] The third cleaning mechanism 130 has an air supply source 160, flow paths 213, 223, 109, 107, and 101, an electromagnetic valve 173, a valve 108, a nozzle 140, a branch path 102, a pump 191, and a tank 181. The air supply source 160, the flow path 101, the branch path 102, the pump 191, and the tank 181 have the same configuration as the second cleaning mechanism 120, and therefore a description thereof will be omitted.

[0057] The flow path 213 connects the air supply source 160 and the electromagnetic valve 173. The electromagnetic valve 173 is provided at one end of the flow path 223. The electromagnetic valve 173 opens the flow path 223 when it is in an excited state, and closes the flow path 223 when it is in a non-excited state.

[0058] A valve 108 is provided at the other end of the flow path 223. The valve 108 is connected to one end of the flow path 109. The valve 108 is a mechanical valve that can open the flow path 109. When the electromagnetic valve 173 is in an excited state and air is supplied to the flow path 223 from the air supply source 160, the valve 108 opens the flow path 109. When the electromagnetic valve 173 is in a non-excited state and air is not supplied to the flow path 223 from the air supply source 160, the valve 103 closes the flow path 109.

[0059] The other end of flow path 109 is connected to nozzle 140. Nozzle 140 is provided at the lower end of spindle head 7 and is cylindrical and opens in the vertical direction. The inner surface of nozzle 140 covers the lower end of spindle 9 (see FIG. 6). A ring-shaped nozzle hole (not shown) that opens inward in a substantially horizontal direction is formed at the lower end of nozzle 140.

[0060] One end of the flow path 107 is connected to a valve 108. The other end of the flow path 107 is connected to the branch path 102. A pump 192 supplies the cleaning liquid stored in a tank 181 to the nozzle 140. The nozzle 140 to which the cleaning liquid has been supplied ejects a jet flow c (see FIGS. 6 and 8) in a substantially horizontal direction from the nozzle hole. The jet flow c cleans the lower surface 96 of the main shaft 9.

[0061] <Electrical configuration of the control device 30 and the machine tool 1> 9, the control device 30 has a CPU 31, a ROM 32, a RAM 33, a storage device 34, an input / output interface 35, drive circuits 61 to 72, an input device 37, a display device 38, and an output device 39. The CPU 31 controls the control device 30. The ROM 32 stores a control program for executing main processing and the like, which will be described later. The RAM 33 stores various data during processing.

[0062] The storage device 34 is a non-volatile memory and stores the machining program and retry information described below. The machining program is a program for machining a workpiece, and in this embodiment is an NC program. The machining program may be a program written in C language or the like. The NC program is made up of multiple blocks. Each block includes at least one command, such as a tool change command, a cutting command, a positioning command, or an end command. The tool change command is a control command for changing tools using the tool changer 20. The cutting command is a control command for rotating the spindle 9 while moving the spindle 9 and the table 13 relative to each other, thereby cutting the workpiece. The positioning command is a control command for positioning the table 13 and the spindle 9. The end command is a control command for terminating execution of the NC program.

[0063] The input / output interface 35 is electrically connected to the CPU 31, ROM 32, RAM 33, storage device 34, drive circuits 61 to 72, and input device 37, and performs input and output of various signals. The input device 37 and display device 38 are provided on an operation panel 36. The operation panel 36 is provided on the outer wall of a cover (not shown) that covers the machine tool 1. The input device 37 receives input of various information, operation instructions, etc., and inputs them to the CPU 31.

[0064] The drive circuit 61 is electrically connected to the Z-axis motor 51 and encoder 51a. The drive circuit 62 is electrically connected to the spindle motor 52 and encoder 52a. The drive circuit 63 is electrically connected to the X-axis motor 53 and encoder 53a. The drive circuit 64 is electrically connected to the Y-axis motor 54 and encoder 54a. The drive circuit 65 is electrically connected to the magazine motor 55 and encoder 55a.

[0065] Based on commands input from CPU 31, drive circuits 61, 62, 63, 64, and 65 output drive currents to Z-axis motor 51, spindle motor 52, X-axis motor 53, Y-axis motor 54, and magazine motor 55. Z-axis motor 51, spindle motor 52, X-axis motor 53, Y-axis motor 54, and magazine motor 55 are servo motors that rotate in response to the input drive currents. Drive circuits 61, 62, 63, 64, and 65 output drive currents as return values ​​to input / output interface 35.

[0066] Encoder 51a is electrically connected to drive circuit 61 and Z-axis motor 51. Encoder 52a is electrically connected to drive circuit 62 and spindle motor 52. Encoder 53a is electrically connected to drive circuit 63 and X-axis motor 53. Encoder 54a is electrically connected to drive circuit 64 and Y-axis motor 54. Encoder 55a is electrically connected to drive circuit 65 and magazine motor 55. Encoders 51a, 52a, 53a, 54a, and 55a are all absolute value encoders, and output feedback signals indicating the rotation angles of Z-axis motor 51, spindle motor 52, X-axis motor 53, Y-axis motor 54, and magazine motor 55 to drive circuits 61, 62, 63, 64, and 65.

[0067] Based on the rotation angle of Z-axis motor 51 output from encoder 51a, CPU 31 estimates the rotation angle of ball screw 41 connected to Z-axis motor 51, and estimates the position in the Z-axis direction (hereinafter referred to as Z-axis position) of spindle 9 that moves due to the rotation of ball screw 41. The Z-axis position is a relative position in the Z-axis direction with respect to the machining origin.

[0068] Drive circuit 66 is electrically connected to pump 191. Drive circuit 67 is electrically connected to pump 192. Drive circuits 66 and 67 control pumps 191 and 192 based on commands input from CPU 31. Drive circuit 68 is electrically connected to solenoid valve 171. Drive circuit 69 is electrically connected to solenoid valve 172. Drive circuit 70 is electrically connected to solenoid valve 173. Drive circuits 68, 69 and 70 place solenoid valves 171, 172 and 173 in an excited state or a non-excited state based on commands input from CPU 31.

[0069] The drive circuit 71 is electrically connected to the display device 38. The display device has a general-purpose liquid crystal display and displays various screens. Based on commands input from the CPU 31, the drive circuit 71 causes the display device 38 to display images including various information, abnormality information, etc.

[0070] The drive circuit 72 is electrically connected to the output device 39. The output device 39 outputs a signal for communicating with another device. The other device may be, for example, a general-purpose PC (personal computer) that controls multiple machine tools 1, a PLC (programmable logic controller), or the like. The output device 39 communicates with the other device via serial communication, but may also communicate via parallel communication. Examples of signals output by the output device 39 are bit signals and macros. The drive circuit 72 causes the output device 39 to output a signal to the other device based on a command input from the CPU 31.

[0071] <Variations in disturbance force and its derivative during wearing> Fig. 10(A) is a graph showing the relationship between the Z-axis position (horizontal axis) and the disturbance force (vertical axis) applied to Z-axis motor 51 during the mounting operation. In Fig. 10(A), processing has been performed using a low-pass filter that removes the natural vibration of machine tool 1 in order to eliminate the influence of vibrations, etc. of machine tool 1. During the mounting operation, the rotation angle of Z-axis motor 51 changes in the negative direction.

[0072] The disturbance force applied to the Z-axis motor 51 is a force acting on the Z-axis motor 51 as a reaction force due to the driving of the Z-axis motor 51. The disturbance force is included in the torque of the Z-axis motor 51 and satisfies the relationship of the following equation 1.

number

[0073] The CPU 31 obtains the drive current of the Z-axis motor 51 from the drive circuit 61 and obtains the rotation angle θ of the Z-axis motor 51 from the encoder 51 a, thereby calculating the torque T m Then, the CPU 31 acquires the torque T m , and obtain the disturbance force F based on the rotation angle θ.

[0074] FIG. 10(B) is a graph showing the relationship between the Z-axis position (horizontal axis) of Z-axis motor 51 and the time differential value of disturbance force F (hereinafter referred to as differential value f) (vertical axis) during the mounting operation. In FIG. 10(B), the Z-axis position when differential value f is minimum during the mounting operation is stored in RAM 33. Hereinafter, the Z-axis position when differential value f is minimum will be referred to as the detection position. When main shaft 9 is located at the detection position during the mounting operation, plate cam 47 moves away from cam follower 49.

[0075] <Tool T mounted on spindle 9> A state in which the tool T is attached to the spindle 9 in such a manner that the workpiece can be machined by the tool T and cutting accuracy is not affected is called a "completely attached state." In contrast, there are cases in which the tool T is incompletely attached to the spindle 9, resulting in a foreign matter adhesion state. The foreign matter adhesion state is a state in which the tool T is attached to the spindle 9 with foreign matter adhering to at least one of the space between the inner surface 92a of the spindle 9 and the tapered surface 16a of the tool T, or the space between the lower surface 96 of the spindle 9 and the upper surface 15a of the tool T. The foreign matter is, for example, chips generated from the workpiece during cutting.

[0076] In the foreign matter attached state, the position at which the gripping portion 85 grips the pull stud 17 is lower than the position in the fully attached state due to the attached foreign matter. Therefore, if the workpiece is machined with the foreign matter attached, the position of the tip of the tool T will be different from that in the fully attached state, which could result in a decrease in the machining accuracy of the workpiece. Hereinafter, the fully attached state and the foreign matter attached state will be collectively referred to as the attached state.

[0077] <Determining wearing status> To determine the mounting state, the CPU 31 of the control device 30 acquires the Z-axis position of the spindle 9 during the mounting operation and the disturbance force F applied to the Z-axis motor 51 at a predetermined period (e.g., 0.5 ms). The CPU 31 acquires the Z-axis position of the spindle 9 by acquiring the rotation angle θ from the encoder 51a.

[0078] The CPU 31 applies a low-pass filter to the acquired disturbance force F, and then performs time differentiation to calculate a differential value f. The CPU 31 associates the calculated differential value f with the Z-axis position of the spindle 9 and stores them in the RAM 33. The CPU 31 determines the detection position from the fluctuation of the differential value f stored in the RAM 33 (see FIG. 10(B)).

[0079] When a foreign object is attached, the position of the pull stud 17 relative to the spindle 9 is lower than when the pull stud 17 is fully attached. Therefore, when the pull stud 17 is attached, the timing at which the plate cam 47 separates from the cam follower 49 during the attachment operation is earlier than when the pull stud 17 is fully attached. Therefore, when the pull stud 17 is attached, the disturbance force F (dashed line in FIG. 10(A)) and the differential value f (dashed line in FIG. 10(B)), which vary depending on the Z-axis position, are shifted in the positive direction along the Z axis compared to when the pull stud 17 is fully attached (solid lines in FIGS. 10(A) and 10(B)). Therefore, the CPU 31 can determine whether the attachment state is a foreign object attached state based on the detection position determined by the attachment operation.

[0080] <Cleaning by the cleaning device 100> When the CPU 31 determines that the attachment state is a foreign matter adhesion state, it executes a detachment operation to detach the tool T from the spindle 9. The CPU 31 performs cleaning of the spindle 9 and the tool T by the cleaning device 100 in order to remove foreign matter adhering to the tool T and the spindle 9. The cleaning device 100 cleans the inner surface 92a of the spindle 9 by the first cleaning mechanism 110 and the bottom surface 96 of the spindle 9 by the third cleaning mechanism 130. The cleaning device 100 cleans the tapered surface 16a and the top surface 15a of the tool T by the second cleaning mechanism 120. Hereinafter, the operation of the cleaning device 100 to perform cleaning will be referred to as a cleaning operation.

[0081] After performing the cleaning operation, the CPU 31 performs the mounting operation again to mount the tool T on the spindle 9. The CPU 31 determines the mounting state in the re-mounting operation. The detachment operation, cleaning operation, and mounting operation that are performed again when it is determined that a foreign substance is attached, and the process of determining the mounting state in the mounting operation are collectively referred to as retry processing. The detachment operation, cleaning operation, mounting operation, and mounting operation performed in the retry processing are referred to as retry operations. If the CPU 31 determines that the mounting state is a foreign substance attached state in the retry processing, it performs the retry processing again. The CPU 31 counts the number of retries the retry processing has been performed for each tool T and stores the count in the memory device 34.

[0082] Referring to FIG. 8, the states of each valve when a cleaning operation is not being performed and when a cleaning operation is being performed on the tool T and spindle 9 will be described. When a cleaning operation is not being performed, the CPU 31 de-energizes all of the electromagnetic valves 171, 172, and 173. Because the electromagnetic valve 171 is de-energized, the flow path 152 is closed, and the valve 111 closes the flow path 153. Cleaning liquid is not supplied from the pump 191 to the communication hole 56, and the jet stream a is not sprayed into the mounting hole 92. Because the electromagnetic valve 172 is de-energized, the flow path 222 is closed, and the valve 103 closes the branch path 104. Cleaning liquid is not supplied from the pump 192 to the nozzles 131 and 132, and the jet stream b is not sprayed from the nozzles 131 and 132. Because the electromagnetic valve 173 is de-energized, the flow path 223 is closed, and the valve 108 closes the flow path 109. The cleaning liquid is not supplied from the pump 192 to the nozzle 140, and the jet c is not ejected from the nozzle 140.

[0083] When a cleaning operation is performed on the tool T and the spindle 9, the CPU 31 energizes the electromagnetic valves 171, 172, and 173. Because the electromagnetic valve 171 is energized, the flow path 152 is opened, and the valve 111 opens the flow path 153. Cleaning liquid is supplied from the pump 191 to the communication hole 56, and a jet stream a is sprayed into the mounting hole 92. Because the electromagnetic valve 172 is energized, the flow path 222 is opened, and the valve 103 opens the branch path 104. Cleaning liquid is supplied from the pump 192 to the nozzles 131 and 132, and a jet stream b is sprayed from the nozzles 131 and 132. Because the electromagnetic valve 173 is energized, the flow path 223 is opened, and the valve 108 opens the flow path 109. Cleaning liquid is supplied from the pump 192 to the nozzle 140, and a jet stream c is sprayed from the nozzle 140. The cleaning device 100 performs a cleaning operation on the spindle 9 with the jets a and c, and performs a cleaning operation on the tool T with the jet b.

[0084] <Notification process and storage process by retry process> When the attachment state is determined to be a foreign matter attachment state and the retry process is executed, the CPU 31 executes a storage process, a display process, and an output process. The storage process is a process for storing retry information, which will be described later, in the storage device 34.

[0085] The display processing executed by the CPU 31 will be described with reference to Figures 11 to 13. The display processing displays retry information indicating that the retry processing has been executed on the display device 38 (see Figure 9). The retry information includes, for example, the time when the retry processing was executed, the tool number of the tool T that was the target of the retry processing, the number of retries for each tool T, and the total number of retries in the machining program. The tool number is a number assigned to identify the tool T. Information related to the tool T, such as the tool number and the number of retries for each tool T, is called tool information.

[0086] The display device 38 displays a retry image showing retry information. The retry image includes an alarm history image 310 (see FIG. 11), a cycle time history image 320 (see FIG. 12), and a tool usage history image 330 (see FIG. 13). The following description will be given of a case in which, when a tool change was performed in an NC program with a program name "O0001.NC" that was started at 9:00 on March 1, 2024, a retry process was executed once for each of the tools T with tool numbers 001, 002, 003, and 004. In FIGS. 11 to 13, the left, right, top, and bottom of the paper correspond to the left, right, top, and bottom of the retry image, respectively.

[0087] 11, the alarm history image 310 has an alarm history table 311 and a cycle time history switching area 313. The alarm history table 311 is located at the top of the alarm history image 310. In the alarm history table 311, alarm content, time, and date are displayed in association with each other.

[0088] The alarm contents in the alarm history table 311 display the contents of various abnormalities, including the foreign matter adhesion state. Abnormalities other than the foreign matter adhesion state include, for example, abnormalities of the tool T, such as wear, and program abnormalities, such as an emergency stop. When a retry process is executed, the alarm contents display a message that the retry process has been executed, and the tool number of the tool T that was the target of the retry process. In this embodiment, the tool number is indicated by a number in parentheses in the alarm contents. The time and date in the alarm history table 311 display the time when the retry process was executed.

[0089] The alarm history table 311 displays the latest alarm details from the top. Therefore, the alarm history table 311 displays, from the top, that retry processing was performed when changing tools T with tool numbers 004, 003, 002, and 001. By checking the alarm history image 310, the user can understand when and for which tool T the retry processing was performed.

[0090] The cycle time history switching area 313 is located below the alarm history table 311. The cycle time history switching area 313 is an area that accepts an input for switching the image displayed by the display device 38 from the alarm history image 310 to a cycle time history image 320 (see FIG. 12).

[0091] 12, the cycle time history image 320 has a cycle time history table 321, an alarm history switching area 322, and a tool use history switching area 324. The cycle time history table 321 is located at the top of the cycle time history image 320. In the cycle time history table 321, the program name, program language, and operation start time are displayed in association with each other.

[0092] The program name in the cycle time history table 321 displays the program name of the machining program executed by the CPU 31. The program language displays the program language of the machining program executed by the CPU 31. The operation start time displays the time when the CPU 31 started executing the machining program.

[0093] The cycle time history table 321 displays the most recent machining programs from the top down. The cycle time history table 321 displays both machining programs for which retry processing was performed and machining programs for which retry processing was not performed. The cycle time history table 321 highlights the program name, programming language, and operation start time of the machining program for which retry processing was performed in italics. Therefore, the cycle time history table 321 highlights the NC program with the program name "O0001.NC" that started at 9:00 AM on March 1, 2024. The highlighting style may be changed as needed. For example, the program name, programming language, and operation start time of the machining program for which retry processing was performed may be changed by appropriately combining the text color, text format, text size, and frame color. By checking the cycle time history image 320, the user can determine when and for which program retry processing was performed.

[0094] The alarm history switching area 322 and the tool usage history switching area 324 are located below the cycle time history table 321. The alarm history switching area 322 is located to the left of the tool usage history switching area 324. The alarm history switching area 322 is an area that receives an input for switching the image displayed by the display device 38 from the cycle time history image 320 to the alarm history image 310 (see FIG. 11). The tool usage history switching area 324 is an area that receives an input for switching the image displayed by the display device 38 from the cycle time history image 320 to the tool usage history image 330 (see FIG. 13). In this embodiment, when one machining program is selected from the cycle time history table 321, the cycle time history image 320 is switched to the tool usage history image 330. Hereinafter, one machining program selected from the cycle time history table 321 will be referred to as a selected program. In other words, the selected program is identified by the machining program and the execution start time of the machining program.

[0095] 13, the tool use history image 330 is displayed after being switched from the cycle time history image 320. The tool use history image 330 has a tool use history table 331 and a cycle time history switching area 333. The tool use history table 331 is located at the top of the tool use history image 330. The tool use history table 331 includes a program history table 338 and a tool history table 339.

[0096] The program history table 338 is the upper part of the tool usage history table 331. In the program history table 338, the program name, total number of retries, cycle time, cutting time, non-cutting time, and cutting time rate are displayed in association with each other. The program name in the program history table 338 displays the name of the selected program. The total number of retries displays the total number of retries executed in the selected program.

[0097] The cycle time indicates the time from the start to the completion of the selected program. The cutting time indicates the time spent machining the workpiece within the cycle time of the selected program. More specifically, the cutting time is the time spent rotating the spindle 9 to machine the workpiece in accordance with the cutting commands of the machining program. The non-cutting time indicates the time spent in the cycle time of the selected program other than cutting. That is, in this embodiment, the cycle time of the selected program is the sum of the cutting time and non-cutting time in the program history table 338. The non-cutting time includes, for example, the time it takes for the spindle 9 to be positioned to the specified position in accordance with a positioning command, the execution time of the removal operation executed in accordance with a tool change command, the execution time of the rotation of the tool magazine 21, the execution time of the mounting operation, and the execution time of the retry operation when a retry process is executed. When a retry process is executed, the retry operation is performed, and the non-cutting time increases. The cutting time rate indicates the proportion of the cycle time that cutting time accounts for, expressed as a percentage.

[0098] By checking the program history table 338, the user can understand how many retry processes have been executed in the selected program and how much the cycle time has increased due to the retry processes.

[0099] The tool history table 339 is the lower part of the tool usage history table 331. In the tool history table 339, the machining number, tool number, measurement time, cutting time, non-cutting time, and number of retries are displayed in association with each other for the selected program displayed in the program history table 338.

[0100] The machining number in the tool history table 339 indicates the number of the machining of the workpiece performed in the selected program. The machining number "6" indicates that the machining of the workpiece was performed the sixth time in the selected program. The tool number in the tool history table 339 is the tool number of the tool T that was attached to the spindle 9 in the machining indicated by the machining number. The measured time in the tool history table 339 indicates the total time that the tool T indicated by the tool number was attached to the spindle 9. The cutting time in the tool history table 339 indicates the cutting time of the machining indicated by the machining number. The non-cutting time in the tool history table 339 indicates the non-cutting time of the machining indicated by the machining number. In other words, in this embodiment, the sum of the cutting time and non-cutting time in the tool history table 339 is the measured time for the machining number. The number of retries in the tool history table 339 indicates the number of retries performed when the tool T indicated by the tool number was changed.

[0101] In the tool history table 339, the machining numbers are displayed in ascending order. In the tool history table 339, the machining number, tool number, measurement time, cutting time, non-cutting time, and number of retries for the tool T for which the retry process was executed are highlighted in italics. In the tool history table 339, the machining numbers "2" to "5" are highlighted. Note that the highlighting manner may be changed as appropriate, and for example, the program name, program language, and operation start time of the machining program for which the retry process was executed may be changed by appropriately combining the color of the text, the format of the text, the size of the text, the color of the box, etc.

[0102] By checking the tool history table 339, the user can understand which tool changes in the selected program were retried, how many retry changes were made for each tool change, and how much the measurement time increased for each tool change.

[0103] The cycle time history switching area 333 is located below the tool usage history table 331. The cycle time history switching area 333 is an area for receiving an input for switching the image displayed by the display device 38 from the tool usage history image 330 to the cycle time history image 320 (see FIG. 12).

[0104] The user can ascertain the time when the retry process was executed by checking the alarm history image 310. The user can ascertain the machining program for which the retry process was executed by checking the cycle time history image 320 and referring to the time when the retry process was executed as understood in the alarm history image 310. The user can ascertain how much the cycle time increased due to the retry process and how many retries were executed for which tool changes by checking the tool usage history image 330 and referring to the machining program for which the retry process was executed as understood in the cycle time history image 320.

[0105] The output processing executed by CPU 31 will now be described. In the output processing, a retry signal indicating retry information is output by output device 39 (see FIG. 9). In this embodiment, the retry signal is a signal including a command to start executing a program for notifying the execution of the retry processing. In the output processing, the retry signal is output from output device 39 to, for example, a general-purpose PC that controls multiple machine tools 1 in an integrated manner. The user can know that the retry processing has been executed by checking the general-purpose PC. In this way, the output of a signal by the output processing is also one way of notifying the execution of the retry processing.

[0106] <Main processing> 14 to 16, the main processing executed by CPU 31 will be described. Using input device 37, the user selects one NC program from the plurality of NC programs stored in storage device 34 and inputs a cutting processing start instruction to CPU 31. Upon receiving the start instruction, CPU 31 starts the main processing by executing a control program called from ROM 32.

[0107] 14, the CPU 31 sets the value of the number of retries for each tool T used in the selected NC program and the value of the total number of retries for the selected NC program to 0 (S1). The CPU 31 reads the selected NC program (S2). The CPU 31 interprets one line of control commands from the read NC program (S3).

[0108] The CPU 31 determines whether the interpreted control command includes an end command (S4). If the CPU 31 determines that the interpreted control command does not include an end command (S4: NO), it determines whether the interpreted control command includes a tool change command (S5). If the CPU 31 determines that the interpreted control command does not include a tool change command (S5: NO), it executes various processes based on the interpreted control command (S6). The various processes include, for example, positioning the spindle 9 based on a positioning command. The CPU 31 returns the process to S2. If the CPU 31 determines that the interpreted control command includes a tool change command (S5: YES), it proceeds to S11.

[0109] 15, the CPU 31 acquires tool information of the tool T to be attached to the spindle 9 by tool change (S11). The CPU 31 performs a detachment operation (S12). In the detachment operation, the CPU 31 rotates the Z-axis motor 51 in the forward direction to raise the spindle 9 to the ATC origin. The tool T attached to the spindle 9 is detached from the spindle 9 by the detachment operation and loaded onto the tool changer 20. The CPU 31 drives the magazine motor 55 to rotate the tool magazine 21, and indexes the grip arm 23, which grips the tool T to be attached to the spindle 9, to the tool change position based on the tool information acquired in S11 (S13).

[0110] The CPU 31 starts acquiring the rotation angle θ of the Z-axis motor 51 and the disturbance force F (S14). The CPU 31 performs the mounting operation (S15). In the mounting operation, the CPU 31 rotates the Z-axis motor 51 in the reverse direction and lowers the spindle 9 from the ATC origin to the processing origin. The CPU 31 stops acquiring the rotation angle θ of the Z-axis motor 51 and the disturbance force F, which was started in the processing of S14 (S16).

[0111] The CPU 31 generates a waveform of the differential value f (see FIG. 10(B)) (S17). In the process of S17, the CPU 31 applies a low-pass filter to the disturbance force F acquired during the processes of S14 to S16, and then performs time differentiation to calculate the differential value f. The CPU 31 estimates the Z-axis position of the spindle 9 based on the rotation angle θ of the Z-axis motor 51. The CPU 31 generates a waveform of the differential value f by associating the calculated differential value f with the estimated Z-axis position of the spindle 9, and stores the waveform in the RAM 33. The CPU 31 determines the detection position from the generated waveform of the differential value f (S18).

[0112] Based on the determined detection position, the CPU 31 determines whether the attachment state is a foreign matter attachment state (S19). In the determination of S19, the CPU 31 determines whether the detection position is on the positive side of the Z axis direction from a predetermined upper limit position. If the detection position is on the negative side of the Z axis direction from the upper limit position, the CPU 31 determines that the attachment state is not a foreign matter attachment state (S19: NO) and returns the process to S4 (see FIG. 14). If the detection position is on the positive side of the Z axis direction from the upper limit position, the CPU 31 determines that the attachment state is a foreign matter attachment state (S19: YES) and proceeds to S21 (see FIG. 16).

[0113] 16, the CPU 31 adds 1 to the value of the number of retries for the tool T whose tool information was acquired in S11 and the value of the total number of retries in the machining program (S21). The CPU 31 determines whether the value of the total number of retries has reached a predetermined threshold value (S23). If the CPU 31 determines that the value of the total number of retries has not reached the threshold value (S23: NO), the CPU 31 shifts the process to S32 to execute the retry process.

[0114] The CPU 31 performs the detachment operation as a retry process (S32). S32 is the same process as S12. The CPU 31 executes the cleaning process (S33). In the cleaning process, the CPU 31 energizes the electromagnetic valves 171, 172, and 173, and performs the cleaning operation on the spindle 9 and the tool T using the cleaning device 100.

[0115] The CPU 31 starts acquiring the rotation angle θ of the Z-axis motor 51 and the disturbance force F (S34). The CPU 31 performs the mounting operation (S35). The CPU 31 stops acquiring the rotation angle θ of the Z-axis motor 51 and the disturbance force F that was started in the processing of S14 (S36). The CPU 31 generates a waveform of the differential value f (S37). The CPU 31 determines the detection position from the waveform of the generated differential value f (S38). S34 to S38 are the same processing as S14 to S18.

[0116] The CPU 31 executes a storage process (S39). As part of the storage process, the CPU 31 stores retry information in the storage device 34. The retry information stored includes the time when the retry process was executed, the tool number of the tool T that was the target of the retry process, the number of retries for each tool T, and the total number of retries in the machining program. The time when the retry process was executed is the time when the detachment operation in S32 was started.

[0117] The CPU 31 determines whether the attachment state is a foreign matter attached state (S41). S41 is the same process as S19. If the CPU 31 determines that the attachment state is a foreign matter attached state (S41: YES), the process returns to S21. The CPU 31 repeatedly executes the processes of S32 to S41 until the total number of retries reaches the threshold value. The retry process in this embodiment is the processes of S32 to S38 and S41.

[0118] When the CPU 31 determines that the mounting state is not a foreign matter adhesion state (S41: NO), it executes a display process (S42) and returns the process to S4 (see FIG. 14). As the display process, the CPU 31 displays a retry image on the display device 38. More specifically, the CPU 31 switchably displays an alarm history image 310 (see FIG. 11), a cycle time history image 320 (see FIG. 12), and a tool usage history image 330 (see FIG. 13) on the display device 38. The alarm history image 310 displays the history of retry information stored in the storage process (S39).

[0119] When the CPU 31 determines that the total number of retries has reached the threshold value (S23: YES), it executes output processing (S24) and ends the main processing. As the output processing, the CPU 31 outputs a retry signal to a general-purpose PC that controls multiple machine tools 1 in an integrated manner.

[0120] As shown in FIG. 14, when the CPU 31 determines that the interpreted control command includes an end command (S4: YES), it ends the machining of the workpiece based on the NC program (S9) and ends the main processing.

[0121] <Actions and Effects of This Embodiment> As described above, the CPU 31 of the control device 30 performs the mounting operation using the tool changer 20 (S15). The CPU 31 determines whether the mounting state of the spindle 9 after the mounting operation is a foreign matter attached state (S19). If the CPU 31 determines that the mounting state is a foreign matter attached state, it executes a retry process (S32 to S38, S41). The CPU 31 executes a storage process (S39) for storing retry information and a display process (S42) for displaying a retry image. This allows the user to know that the retry process has been executed by checking the retry information stored by the storage process or the retry image displayed by the display process. Therefore, the control device 30 allows the user to easily know that the cycle time has increased due to the execution of the retry process.

[0122] When a retry process is executed, the CPU 31 notifies the user by displaying retry information on the display device 38. This allows the user to know that the retry process has been executed by checking the retry image displayed on the display device 38. Therefore, the control device 30 allows the user to easily know that the cycle time has increased due to the execution of the retry process.

[0123] When the retry process is executed, the CPU 31 switchably displays the alarm history image 310, the cycle time history image 320, and the tool usage history image 330 on the display device 38. This allows the user to know that the retry process has been executed by checking the alarm history image 310, the cycle time history image 320, and the tool usage history image 330 displayed on the display device 38. Therefore, even when the control device 30 notifies using images, the user can easily know that the cycle time has increased due to the execution of the retry process.

[0124] The CPU 31 displays the time when the retry process was executed in the alarm history image 310. This allows the user to know the time when the retry process was executed by checking the alarm history image 310 displayed on the display device 38. Therefore, by the control device 30 displaying the time when the retry process was executed, the user can easily know the time when the cycle time increased.

[0125] The CPU 31 displays the tool information of the tool T that was the target of the detachment operation and the attachment operation of the retry process in the tool use history image 330. This allows the user to easily understand the tool T that was the target of the detachment operation and the attachment operation from the tool information by checking the tool use history image 330 displayed on the display device 38.

[0126] The CPU 31 displays, as tool information, the tool number of the tool T that was the target of the detachment operation and the attachment operation of the retry process in the tool use history image 330. This allows the user to easily understand the tool T that was the target of the detachment operation and the attachment operation by checking the tool number in the tool use history image 330. Therefore, the control device 30 allows the user to easily understand the tool number of the tool T that was the target of the retry process.

[0127] The CPU 31 displays the number of retries for each tool T in the machining program as tool information in the tool usage history image 330. This allows the user to easily understand the frequency with which retry processing is executed for each tool T by checking the number of retries for each tool T in the tool usage history image 330.

[0128] The CPU 31 displays the total number of retries in the machining program in the tool usage history image 330. By checking the total number of retries in the tool usage history image 330, the user can easily understand how often retry processing is executed in the machining program.

[0129] The CPU 31 executes a storage process (S39) and a display process (S42). In the display process, the CPU 31 displays the history of retry information stored in the storage process on the alarm history image 310. This allows the user to easily understand the tendency for retry processing to be executed in the machining program by checking the history of retry information on the alarm history image 310.

[0130] When the retry process is executed, the CPU 31 notifies the user by outputting a retry signal from the output device 39. This allows the user to know that the retry process has been executed by checking an external device such as a general-purpose PC that has received the retry signal output from the output device 39.

[0131] Between the detachment operation (S32) and the attachment operation (S35) by the retry process, the CPU 31 executes a cleaning process (S33) in which the cleaning device 100 performs a cleaning operation on the spindle 9 and the tool T. According to this, the control device 30 removes foreign matter adhering to the tool T and the spindle 9 by the cleaning process, and eliminates the foreign matter adhering state. Therefore, the control device 30 can suppress an increase in cycle time due to repeatedly executing the retry process.

[0132] <Modification> The present invention can be modified in various ways from the above-described embodiment. The various modifications described below can be combined with each other as long as no contradictions arise. The tool changer 20 is not limited to a turret type, and may be, for example, an arm type.

[0133] In the above embodiment, whether the mounting state is in a foreign matter adhesion state is determined based on whether the detection position is located on the positive side of the Z-axis direction from a predetermined upper limit position, but the method of determining whether the foreign matter adhesion state is present is not limited to this. For example, the transition of the detection position may be stored, and a statistical value obtained by statistically processing the stored transition of the detection position may be used as a threshold value for the foreign matter adhesion state to determine whether the foreign matter adhesion state is present. A reference value may be calculated from the average value of the past N (N≧1) detection positions, and the current detection position may be subtracted from the reference value to calculate a detection value. If the detection value is equal to or less than the threshold value, it may be determined that the foreign matter adhesion state is present.

[0134] In the above embodiment, the Z-axis position where the varying differential value f is minimum is used as the detection position, but for example, the Z-axis position where the differential value f is maximum may also be used as the detection position. In the above embodiment, whether or not a foreign substance is attached is determined based on the estimated Z-axis position (mm) of the spindle 9, but for example, whether or not a foreign substance is attached may also be determined based on the rotation angle θ (rad) of the Z-axis motor 51. In the above embodiment, whether or not a foreign substance is attached is determined based on fluctuations in the differential value f, but for example, whether or not a foreign substance is attached may also be determined based on the disturbance force F or torque T m It may be possible to determine whether or not a foreign substance is attached based on the fluctuation of the value.

[0135] The retry process may be modified as appropriate as long as it includes the detachment operation, the attachment operation, and the determination of whether foreign matter is attached. For example, the cleaning process may not be performed in the retry process. In this case, step S33 may be omitted from the main process.

[0136] In the above embodiment, when a retry process is executed, a storage process, a display process, and an output process are executed, but at least one of the storage process, display process, and output process may be executed. For example, only the storage process may be executed when a retry process is executed. Only the display process may be executed when a retry process is executed. Only the output process may be executed when a retry process is executed. Only the storage process and the display process may be executed when a retry process is executed. Only the storage process and the output process may be executed when a retry process is executed. Only the display process and the output process may be executed when a retry process is executed.

[0137] Display device 38 and output device 39, which are components for notifying retry information, are not limited to being included in control device 30. Display device 38 and output device 39 may be included in machine tool 1, or may be included in a component different from control device 30 and machine tool 1 (for example, a general-purpose PC). Memory device 34, which is a component for storing retry information, is not limited to being included in control device 30. Memory device 34 may be included in machine tool 1, or may be included in a component different from control device 30 and machine tool 1 (for example, a general-purpose PC).

[0138] In the above embodiment, the execution of the retry process is notified by displaying a retry image by the display device 38 in the display process and outputting a retry signal by the output device 39 in the output process, but the manner of notifying the execution of the retry process may be changed as appropriate. For example, the execution of the retry process may be notified by emitting a sound from a buzzer, or by emitting light from a lamp.

[0139] The manner in which the retry image is displayed by the display device 38 may be changed as appropriate. The retry image may display only the alarm history image 310. The retry image may display only the cycle time history image 320. The retry image may display only the tool usage history image 330. The retry image may display only the alarm history image 310 and the cycle time history image 320 in a switchable manner. The retry image may display only the alarm history image 310 and the tool usage history image 330 in a switchable manner. The retry image may display only the cycle time history image 320 and the tool usage history image 330 in a switchable manner. The retry image may display an image different from the alarm history image 310, the cycle time history image 320, and the tool usage history image 330. The retry image may display, for example, a number indicating the block or line in the machining program where the retry process was executed.

[0140] The display device 38 does not have to display the time when the retry process was executed. The display device 38 may only display the date when the retry process was executed. The display device 38 may only display the time when the retry process was executed. The display device 38 does not have to display the total number of retries in the machining program.

[0141] The display device 38 does not have to display tool information of the tool T that was the target of the detachment operation and attachment operation of the retry process. The display device 38 does not have to display the tool number of the tool T that was the target of the detachment operation and attachment operation of the retry process. The display device 38 does not have to display the number of retries for each tool T in the machining program. The display device 38 may display tool information other than the tool number and the number of retries as tool information of the tool T that was the target of the detachment operation and attachment operation of the retry process. The display device 38 may, for example, display the number of times the tool T has been used as tool information of the tool T that was the target of the detachment operation and attachment operation of the retry process.

[0142] The CPU 31 may not notify the history of retry information stored in the storage process by the display device 38 in the display process. The CPU 31 may output the history of retry information stored in the storage process by the output device 39 in the output process. The CPU 31 may notify the history of retry information stored in the storage process by a configuration different from the display device 38 and the output device 39 (for example, a buzzer or a lamp).

[0143] In the above embodiment, the cleaning device 100 cleans both the tool T and the spindle 9 during the cleaning process. In contrast, the cleaning device 100 may clean only the tool T or only the spindle 9 during the cleaning process. The cleaning device 100 may also clean the table 13. The configuration of the cleaning device 100 may be changed as appropriate. The cleaning device 100 performs cleaning using a cleaning liquid, but may also perform cleaning by spraying air, for example. The cleaning device 100 may also perform cleaning by wiping the tool T and the spindle 9 using a solid object such as a brush, sponge, or rubber.

[0144] Other modifications will now be described. The configuration of the Z-axis movement mechanism 8 may be modified as appropriate. The Z-axis movement mechanism 8 may have a configuration in which the spindle 9 is moved by the rotation of a Z-axis motor 51, instead of the ball screw 41. The Z-axis movement mechanism 8 may have, instead of the ball screw 41, for example, a slide screw extending in the Z-axis direction or a spline shaft with teeth formed in the Z-axis direction. In this case as well, the CPU 31 can determine the foreign matter adhesion state in the same way as in the above embodiment.

[0145] The control device 30 does not necessarily have to be provided in the machine tool 1, but may be provided separately from the machine tool 1. For example, the control device 30 may be a device (such as a PC or dedicated machine) connected to the machine tool 1. Instead of the CPU 31, for example, a microcomputer, an ASIC (Application Specific Integrated Circuits), an FPGA (Field Programmable Gate Array), or the like may be used as a processor. The mode setting process, tool replacement process, and object cleaning process may each be distributed and processed by multiple processors.

[0146] Non-transitory storage media such as ROM 32 and storage device 34 may be any storage media capable of retaining information regardless of the period for which the information is stored. Non-transitory storage media do not have to include temporary storage media (e.g., transmitted signals). The control program may be downloaded (i.e., transmitted as a transmission signal) from a server connected to a network (not shown) and stored in ROM 32 or storage device 34. In this case, the control program may be stored in a non-transitory storage medium such as an HDD provided in the server.

[0147] The CPU 31 may execute the cleaning operation at a timing other than the timing at which it is determined that foreign matter is attached. For example, the CPU 31 may execute the cleaning operation between the detachment operation and the attachment operation during tool replacement.

[0148] The CPU 31 may appropriately modify the method of acquiring the disturbance force F. For example, the CPU 31 may acquire the torque T m and the inertia force (the second term on the right side of Equation 1) may be acquired as the disturbance force F. The CPU 31 does not need to process the rotation angle θ and the disturbance force F using a low-pass filter. In this case, the processes of S25 and S75 may be omitted. The CPU 31 may process the rotation angle θ and the disturbance force F using a high-pass filter, a band-pass filter, a band-stop filter, or the like.

[0149] <Other> The process of S15 is an example of the "mounting process" of the present invention. The process of S19 is an example of the "determination process" of the present invention. The processes of S32 to S38 and S41 are an example of the "retry process" of the present invention. The process of S39 is an example of the "storage process" of the present invention. The processes of S24 and S42 are an example of the "notification process" of the present invention. The processes of S24, S39 and S42 are an example of the "post-processing" of the present invention. The display device 38 and the output device 39 are an example of the "notification mounting" of the present invention. The alarm history image 310, the cycle time history image 320, and the tool usage history image 330 are an example of the "retry image" of the present invention. The process of S33 is an example of the "cleaning process" of the present invention. [Explanation of symbols]

[0150] 1 Machine tools 3 tools 9 Main shaft 20 Tool changer 30 Control device 31 CPU 34 Storage device 38 Display device 39 Output Devices 51 Z-axis motor 81 Alarm history images 82 Cycle time history image 83 Tool usage history image 100 Cleaning mechanism

Claims

1. A spindle on which tools are attached; a tool changer that carries the tool and changes the tool attached to the spindle; A control device for controlling a machine tool comprising: a mounting process in which the tool exchange device performs a mounting operation of the tool on the spindle; a determination process for determining whether or not the tool is attached to the spindle with foreign matter adhering between the spindle and the tool during the attachment operation by the attachment process; a retry process in which, when it is determined by the determination process that the foreign matter is attached, the tool replacement device performs the detachment operation and the attachment operation of the tool, and then determines whether the foreign matter is attached; a post-processing including at least one of a storage process for storing retry information indicating that the retry process has been executed and a notification process for notifying the user of the retry information when the retry process has been executed; A control device characterized by executing the above.

2. When the retry process is executed, at least the notification process is executed in the post-processing; The notification process includes notifying the retry information by a notification device. The control device according to claim 1 ,

3. the notification device includes a display device that displays an image, The notification process includes displaying a retry image indicating the retry information on the display device. The control device according to claim 2 ,

4. The notification process includes:

4. The control device according to claim 3, wherein the retry information displays the time when the retry process was executed.

5. The notification process includes:

4. The control device according to claim 3, wherein the retry information displays tool information of the tool that has been subjected to the detachment operation and the attachment operation in the retry process.

6. The notification process includes:

6. The control device according to claim 5, wherein the tool information displays a tool number assigned to identify the tool that has been subjected to the detachment operation and the attachment operation in the retry process.

7. The notification process includes:

6. The control device according to claim 5, wherein the tool information displays the number of times the retry process is executed for each tool during execution of a machining program for machining a workpiece by the machine tool.

8. The notification process includes:

4. The control device according to claim 3, wherein the retry information displays the total number of times the retry process has been executed during execution of a machining program for machining a workpiece by the machine tool.

9. When the retry process is executed, the storage process and the notification process are executed in the post-processing. The storage process stores the retry information in a storage device, The notification process includes displaying, on the display device, the retry image indicating the history of the retry information stored in the storage device. The control device according to claim 3 ,

10. the notification device includes an output device that outputs a signal for communication; The notification process includes: outputting a retry signal indicating the retry information from the output device; The control device according to claim 2 ,

11. A cleaning process is further performed between the detachment operation and the attachment operation by the retry process, in which at least one of the tool and the spindle is cleaned by a cleaning device. The control device according to claim 1 ,

Images