WO2024241765A1 - Machine tool, and method for controlling machine tool - Google Patents

Abstract

An NC device (11) or a control unit (21) identifies a worker who operates an operation unit such as an operation button (25). The NC device (11) or the control unit (21) confirms a safety education attendance history (32) indicating whether the identified worker is attending safety education that should be attended in advance in order to safely operate a machine tool body (12). The NC device (11) or the control unit (21) determines, in accordance with at least the confirmed safety education attendance history (32) of the worker, whether to permit or disable a machining operation that is executed due to the operator operating the operation unit and is performed on a workpiece by the machine tool body (12).

Description

Machine tool and machine tool control method

This disclosure relates to a machine tool and a method for controlling the machine tool.

Patent Document 1 describes a system that determines the safety level of an operator who operates industrial machinery (machine tools) based on biological information such as the body temperature of the operator and environmental information such as the temperature or humidity of the working environment, and then restricts or releases the restrictions on the operation of the industrial machinery.

JP 2021-64257 A JP 2017-102687 A

　Safety education for workers is important to operate machine tools safely. Traditionally, whether or not a worker has received safety education is managed by personnel. Ideally, machine tools should be operated by workers who have received safety education, but whether or not operation of machine tools should be limited to workers who have received safety education is left to the discretion of the workplace. It is desirable to develop machine tools and machine tool control methods that can make the machine tool operate differently depending on whether the machine tool is operated by a worker who has not received safety education or a worker who has received safety education.

A first aspect of one or more embodiments provides a machine tool having a machine tool main body for machining a workpiece, an NC device for controlling the machine tool main body, and an operation unit operated by an operator to machine the workpiece with the machine tool main body, and an operation panel in which the NC device or a control unit connected to the NC device accepts operation of the operation unit by the operator, the NC device or the control unit identifying the operator who operates the operation unit, checking a safety education attendance history indicating whether the identified operator has taken safety education that should be taken in advance to safely operate the machine tool main body, and determining whether to permit or not permit machining of the workpiece by the machine tool main body executed by the operator operating the operation unit, depending on at least the confirmed safety education attendance history of the operator.

According to a first aspect of one or more embodiments, the operation of the machine tool is switched based on the objective fact of whether or not the operator has received safety training.

A second aspect of one or more embodiments provides a method of controlling a machine tool, in which a control device provided in a machine tool identifies an operator who operates an operating unit operated to cause the machine tool to machine a workpiece, checks a safety education attendance history indicating whether the identified operator has taken the safety education that should be taken in advance to safely operate the machine tool, and determines whether to permit or not permit the operator to operate the operating unit to machine the workpiece by the machine tool, depending on at least the confirmed safety education attendance history of the operator.

According to a second aspect of one or more embodiments, the operation of the machine tool is switched based on the objective fact of whether or not the operator has received safety training.

　According to one or more embodiments of the machine tool and the machine tool control method, the operation of the machine tool can be made different depending on whether the machine tool is operated by an operator who has not received safety training or an operator who has received safety training.

FIG. 1 is a block diagram illustrating a machine tool according to one or more embodiments. FIG. 2 is a diagram illustrating a press brake, an example of a machine tool, according to one or more embodiments. FIG. 3 is a diagram conceptually illustrating a worker information file stored by a machine tool according to one or more embodiments. FIG. 4 is a diagram conceptually illustrating a safety training video file and a safety check work instruction video file to be played by a machine tool according to one or more embodiments. FIG. 5 is a diagram conceptually illustrating a safety training history managed by a machine tool according to one or more embodiments. FIG. 6 is a flow chart illustrating a process for managing the safety training history of each operator by a machine tool according to one or more embodiments. FIG. 7A is a partial flow chart illustrating processing performed by the controller when the machine tool is a press brake in accordance with one or more embodiments. FIG. 7B is a partial flowchart following FIG. 7A illustrating processing performed by the control device when the machine tool is a press brake according to one or more embodiments. FIG. 8 is a flowchart showing a specific process of step S108 shown in FIG. 7A. FIG. 9 is a perspective view showing a test piece used in a press brake safety check operation. FIG. 10 is a diagram showing a press brake safety check operation that an operator should perform using the test piece shown in FIG. FIG. 11 is a diagram showing an example of a message displayed on the display unit in step S110 shown in FIG. 7A. FIG. 12 is a diagram showing an example of a message displayed on the display unit in step S117 shown in FIG. 7B. FIG. 13 is a diagram showing an example of a message displayed on the display unit in step S120 shown in FIG. 7B. FIG. 14 is a flow chart illustrating the process performed by the controller when the machine tool is a laser processing machine according to one or more embodiments. FIG. 15 is a diagram showing an example of a message displayed on the display unit in step S211 shown in FIG. FIG. 16 is a diagram showing an example of a message displayed on the display unit in step S214 shown in FIG. FIG. 17 is a diagram showing an example of a safety training history list image based on the safety training history of each worker.

A machine tool according to one or more embodiments includes a machine tool main body that processes a workpiece, an NC device that controls the machine tool main body, and an operation panel that has an operation unit operated by an operator to process the workpiece with the machine tool main body, and in which the NC device or a control unit connected to the NC device accepts operation of the operation unit by the operator. The NC device or the control unit identifies the operator who operates the operation unit, checks a safety education attendance history that indicates whether the identified operator has taken safety education that should be taken in advance to safely operate the machine tool main body, and determines whether to permit or not permit the machining operation of the workpiece by the machine tool main body, which is executed by the operator operating the operation unit, depending on at least the confirmed safety education attendance history of the operator.

In one or more embodiments of the machine tool control method, a control device provided in the machine tool identifies an operator who operates an operating unit that is operated to allow the machine tool to machine a workpiece, checks a safety education attendance history indicating whether the identified operator has taken the safety education that should be taken in advance to safely operate the machine tool, and determines whether to permit or not permit the operator to operate the operating unit to machine the workpiece by the machine tool, depending on at least the confirmed safety education attendance history of the operator.

Below, a machine tool and a machine tool control method according to one or more embodiments will be specifically described with reference to the accompanying drawings. In FIG. 1, the machine tool 100 includes an NC (Numerical Control) device 11, a machine tool main body 12, and an operation panel 20. A server 30, a processing program creation device 40, and a processing program database 50 are connected to the machine tool 100, for example, via a network. The machine tool 100 is a press brake for bending sheet metal, a laser processing machine for cutting sheet metal, a turret punch press for punching sheet metal, or any other processing machine.

The NC unit 11 controls the machine tool body 12 based on a machining program created by a machining program creation device 40. The machining program creation device 40 can be configured by a computer device that executes a CAM (Computer Aided Manufacturing) program. The machining program database 50 stores the machining program created by the machining program creation device 40. The NC unit 11 may be supplied with a machining program directly from the machining program creation device 40, or may be supplied with a machining program that is read out from the machining program database 50.

The operation panel 20 includes a control unit 21, a display unit 22, a camera 23, a line-of-sight detection unit 24, operation buttons 25, a storage unit 26, and a non-volatile memory 27. The control unit 21 is connected to the NC device 11. The control unit 21 is connected to the display unit 22, the camera 23, the line-of-sight detection unit 24, the operation buttons 25, a storage unit 26, and a non-volatile memory 27. The control unit 21 is composed of, for example, a microprocessor. The display unit 22 can be composed of a liquid crystal panel, or may be a touch panel with a touch pad 221 attached to its surface. The operation buttons 25 and the touch pad 221 are the operation unit. The storage unit 26 is composed of a temporary storage memory. The non-volatile memory 27 stores a worker information file 270, which will be described later.

The server 30 stores a video file 31 and a safety training attendance history 32, which will be described later. The safety training attendance history 32 may be stored in either a non-volatile memory unit provided in the NC device 11 or the machine tool 100.

In the configuration example shown in FIG. 1, the operation panel 20 includes a control unit 21, and the NC device 11 and control unit 21 are configured to work together to control the machine tool 100. The NC device 11 may execute the control executed by the control unit 21. The control unit 21 may accept operation of the operation unit (operation buttons 25 or touch pad 221) by an operator, or the NC device 11 may accept the operation. The NC device 11 and control unit 21 are control devices that control the operation of the machine tool 100. It is sufficient that the control device of the machine tool 100 accepts operation of the operation unit by an operator.

Here, the configuration of the press brake 100PB will be described using as an example the case where the machine tool 100 is the press brake 100PB shown in Figure 2. As shown in Figure 2, the press brake 100PB includes an NC device 11 and a press brake main body 12PB. The press brake main body 12PB includes left and right side frames 120, an upper table 121, and a lower table 122. A punch holder 123 is attached to the upper table 121, and a die holder 124 is attached to the lower table 122. A punch Tp is attached to the punch holder 123, and a die Td is attached to the die holder 124.

The upper table 121 is configured to move up and down by hydraulic cylinders 125L and 125R provided on the left and right. The upper table 121 may also be configured to move up and down by a motor.

A backgauge 126 is provided behind the upper table 121 and the lower table 122. The backgauge 126 has butts 127L and 127R that move left and right along the stretch 128. The butts 127L and 127R are also configured to move in the height direction and the front and rear directions. Before the worker places the metal sheet W on the die Td and bends the metal sheet W, the butts 127L and 127R move to positions corresponding to the die Td. The worker places the back end of the metal sheet W on the die Td so that it butts against the butts 127L and 127R.

A foot pedal 129 is connected to the NC device 11. The foot pedal 129 has a close foot pedal 1291 that lowers the upper table 121 and an open foot pedal 1292 that raises the upper table 121. The foot pedal 129 is also an operating unit.

The operation panel 20 is attached to an L-shaped arm 201 provided on the left side of the press brake main body 12PB. As an example, the operation buttons 25 are arranged below the display unit 22, and the camera 23 is attached to the top of the display unit 22. The gaze detection unit 24 is arranged below the operation buttons 25. The positions of the camera 23 and the gaze detection unit 24 are just an example, and the camera 23 and the gaze detection unit 24 may be arranged near the display unit 22.

The gaze detection unit 24 can be configured with a pair of light-emitting diodes 241 and 242 that irradiate near-infrared light with a wavelength of 850 nm toward the left and right eyes of the worker, and a pair of cameras 243 and 244 that capture images of the left and right eyes. In more detail, the configuration described in Patent Document 2 can be used as the gaze detection unit 24.

The gaze detection unit 24 is provided so that the control unit 21 can determine whether or not the worker is looking at the display unit 22 based on the direction of the worker's gaze. Instead of providing the gaze detection unit 24, the control unit 21 may determine whether or not the worker is looking at the display unit 22 by detecting the worker's face based on the captured image generated by the camera 23. If it is determined whether or not the worker is looking at the display unit 22 based on the detection of the worker's face from the captured image generated by the camera 23 instead of gaze detection by the gaze detection unit 24, the configuration of the operation panel 20 can be simplified.

In the press brake main body 12PB configured as described above, the worker places the metal sheet W to be processed on the die Td. When the worker presses the close foot pedal 1291 to lower the upper table 121, the metal sheet W is sandwiched between the punch Tp and the die Td and bent. However, as will be described later, the press brake 100PB is configured so that the worker cannot bend the metal sheet W unless he or she has received the required safety training beforehand.

Figure 3 conceptually shows the worker information file 270 stored in the non-volatile memory 27. The worker information file 270 stores worker IDs, worker names, facial images (face photographs), and management authority as worker information. It is not essential that the worker information includes worker names and management authority. The worker information file 270 only needs to store one or more facial images of workers in association with each worker ID. The control unit 21 of the operation panel 20 can register the names of each worker entered using the operation buttons 25 and the facial images of each worker captured by the camera 23 in the worker information file 270.

A management authority value of 0 indicates that the user does not have the authority to manage the machine tool 100, and a management authority value of 1 indicates that the user has the authority to manage the machine tool 100. In other words, a worker with a worker ID of 0006 and a management authority value of 1 is the manager of the machine tool 100.

As shown in FIG. 4, video files 31 stored in server 30 include, for example, five safety training video files 311-315 consisting of safety training video files #1-#5, and one safety check work instruction video file 316. Safety training video files #1-#5 have increasingly more advanced content, from safety training video file #1 to safety training video file #5. The number of safety training video files in video file 31 may vary depending on the type of machine tool 100, and video file 31 includes one or more safety training video files.

The number of safety check work instruction video files in video file 31 may also differ depending on the type of machine tool 100. Depending on the type of machine tool 100, video file 31 may not include a safety check work instruction video file. Video file 31 does not include a safety check work instruction video file, or includes one or more safety check work instruction video files. Safety check work instruction video file 316 is assumed to be a safety check work instruction video file for press brake 100PB.

FIG. 5 conceptually shows the safety training attendance history 32 stored in the server 30. In the safety training attendance history 32, a value of 0 indicates that the safety training video file has not been attended, and a value of 1 indicates that the safety training video file has been attended. The control unit 21 and NC device 11 manage and update the safety training attendance history 32 as follows.

A worker who wishes to watch a safety training video, which is a video for safety training, stands in front of the operation panel 20. Then, as shown in FIG. 6, processing is started, and in step S1, the control unit 21 compares the face of the worker captured by the camera 23 with the face image stored in the worker information file 270 to recognize the worker standing in front of the operation panel 20. In other words, the worker's face is authenticated. In step S2, the worker operates the operation button 25 to select the safety training video file that he or she wishes to view. The NC device 11 reads out the selected safety training video file from the server 30 and supplies it to the control unit 21. The control unit 21 stores the read safety training video file in the memory unit 26. The downloaded safety training video file is temporarily stored in the memory unit 26.

In step S3, upon receiving the playback instruction, the control unit 21 plays the safety training video file and displays the safety training video on the display unit 22. In step S4, the control unit 21 acquires gaze information indicating the line of sight of the worker detected by the gaze detection unit 24. If the gaze detection unit 24 is not provided, in step S4, the control unit 21 detects the face of the worker based on the captured image generated by the camera 23. In step S5, the control unit 21 determines whether or not playback of the safety training video file has been completed. If playback has not been completed (NO), the control unit 21 repeats the processes of steps S3 to S5.

If playback of the safety training video file is completed in step S5 (YES), the control unit 21 determines in step S6 whether the worker has viewed the safety training video. The control unit 21 determines that the safety training video has been viewed if the proportion of the time that the worker's gaze is directed toward the display unit 22 relative to the total playback time of the safety training video file is equal to or greater than a predetermined proportion. If the gaze detection unit 24 is not provided, the control unit 21 determines that the safety training video has been viewed if the proportion of the time that the worker's face is detected relative to the total playback time of the safety training video file is equal to or greater than a predetermined proportion.

If the control unit 21 determines in step S6 that the worker has viewed the safety training video (YES), it notifies the NC unit 11 of the worker ID and information indicating the viewed safety training video file, and instructs it to update the safety training attendance history 32. In step S7, the NC unit 11 rewrites the value 0 of the selected safety training video file of the recognized worker in the safety training attendance history 32 to a value 1, thereby recording that the safety training has been completed, and ends the process.

On the other hand, if the control unit 21 determines in step S6 that the worker has only played back the safety training video but has not actually watched it (NO), it instructs the NC unit 11 not to update the safety training attendance history 32. In step S8, the NC unit 11 ends the process without updating the safety training attendance history 32.

In FIG. 6, the control unit 21 determines that the safety training video has been viewed based on the direction of the worker's gaze, but it may also be determined whether or not the safety training video has been viewed as follows. If the safety training video includes content that instructs the operator to operate an operation unit such as the operation button 25, the control unit 21 determines whether or not the operation unit has actually been operated. If the ratio of the number of times the operator actually operated the operation unit to all instructions that instruct the operator to operate the operation unit within the entire playback time of the safety training video file is equal to or greater than a predetermined ratio, the control unit 21 determines that the safety training video has been viewed. The control unit 21 may also determine whether or not the safety training video has been viewed based on both the direction of the worker's gaze or the detection result of the worker's face, and the number of times the operation unit has been operated.

The control unit 21 may use artificial intelligence (AI) to analyze the behavior of the worker and determine whether or not the safety training video has been viewed. There are no limitations on the conditions under which the control unit 21 determines that the safety training video has been viewed.

The flowcharts shown in Figures 7A and 7B will be used to explain the processing executed by the NC device 11 or the control unit 21 when the press brake 100PB bends the metal sheet W. In Figure 7A, when the power to the press brake 100PB is turned on and processing begins, the NC device 11 returns the press brake main body 12PB to the origin in step S101. In step S102, the NC device 11 reads a machining program newly created by the machining program creation device 40 or an existing machining program stored in the machining program database 50.

In step S103, the worker performs die setup to attach punch Tp and die Td to punch holder 123 and die holder 124 at the positions specified by the machining program, respectively, to prepare the workpiece, which is the sheet metal W to be machined. In step S104, the worker presses the start button on the operation buttons 25. In step S105, the control unit 21 recognizes the worker based on the image of the worker captured by camera 23. In step S106, the control unit 21 queries the NC device 11 about the safety training attendance history. The NC device 11 supplies the safety training attendance history of the recognized worker to the control unit 21 from the safety training attendance history 32 stored in the server 30.

In step S107, the control unit 21 determines whether the worker has taken safety training. Using the safety training attendance history 32 shown in FIG. 5 as an example, the control unit 21 may determine that the worker has taken safety training if at least safety training video files #1 to #3 of the five safety training video files consisting of safety training video files #1 to #5 have been taken. The control unit 21 may determine that the worker has taken safety training if all safety training video files #1 to #5 have been taken. It is arbitrary how many of the five safety training video files must be taken to determine that the worker has taken safety training. The number of safety training video files that need to be taken may be varied depending on the type (difficulty) of workpiece machining by the press brake 100PB (machine tool 100).

If the worker has received safety training in step S107 (YES), the control unit 21 instructs the worker to perform a safety check in step S108. When bending the metal sheet W with the press brake 100PB, it is required to perform a safety check using a test piece, which will be described later, to check whether there are any abnormalities in the press brake main body 12PB. Figure 8 shows the detailed processing of step S108.

In FIG. 8, the control unit 21 instructs the NC unit 11 to read the safety check work instruction video file 316. The NC unit 11 reads the safety check work instruction video file 316 from the server 30 and supplies it to the control unit 21. The control unit 21 stores the safety check work instruction video file 316 in the memory unit 26. The downloaded safety check work instruction video file 316 is temporarily stored in the memory unit 26. In step S81, the control unit 21 plays the safety check work instruction video file 316 and displays the safety check work instruction video on the display unit 22.

While the safety check work instruction video is being displayed on the display unit 22, the control unit 21 acquires gaze information indicating the line of sight of the worker detected by the gaze detection unit 24. If the gaze detection unit 24 is not provided, the control unit 21 detects the face of the worker based on the captured image generated by the camera 23.

The press brake 100PB is equipped with a safety device including an emitter that emits a laser beam and is provided at one of the left-right ends of the upper table 121 and the lower table 122, and a receiver that is provided at the other end. The emitter emits a laser beam between the upper table 121 and the lower table 122. If, for example, a hand enters between the upper table 121 and the lower table 122, the laser beam is blocked and the receiver does not receive the laser beam. The NC device 11 is configured to stop the descent of the upper table 121 when the receiver changes from a state in which it receives the laser beam to a state in which it does not receive the laser beam.

The safety confirmation work for the press brake 100PB is a work to confirm that the safety device is operating correctly using the test piece 12TP shown in FIG. 9. The safety confirmation work instruction video in the safety confirmation work instruction video file 316 is a video that instructs the worker to perform the following safety confirmation work.

As shown in Figure 10, the safety device has upper, middle, and lower light-emitting elements 13a to 13f on the rear and front sides. With the upper table 121 positioned upward, the operator grasps the plate-shaped portion with a plate thickness of 10 mm of the test piece 12TP and brings the tip of the cylindrical portion with a diameter of 14 mm into contact with the punch Tp. At this time, the laser beams emitted from the upper and middle light-emitting elements 13a, 13b, 13d, and 13e are blocked by the cylindrical portion. The operator presses down on the close foot pedal 1291 to make sure that the upper table 121 does not descend.

Returning to FIG. 8, the control unit 21 determines whether or not the worker has performed the safety confirmation work shown in FIG. 10 after step S82. In step S82, the control unit 21 determines whether or not the safety confirmation work has been started by pressing the safety work start button. If the safety confirmation work has not been started (NO), the control unit 21 shifts the process to step S88. If the safety confirmation work has been started (YES), the control unit 21 determines in step S83 whether or not the start button has been pressed. If the start button has not been pressed (NO), the control unit 21 shifts the process to step S88.

If the start button is pressed in step S83 (YES), the control unit 21 determines in step S84 whether or not only the designated light-emitting unit of the safety device is blocked. If the control unit 21 obtains information that the designated light-receiving unit of the safety device is not receiving the laser beam, it can determine that only the designated light-emitting unit is blocked. If only the designated light-emitting unit of the safety device is not blocked (NO), the control unit 21 transitions the process to step S88.

If only the light-emitting unit specified in step S84 is blocked (YES), the control unit 21 determines in step S85 whether the close foot pedal 1291 has been pressed. The control unit 21 can determine whether the close foot pedal 1291 has been pressed by obtaining information from the NC device 11 as to whether the close foot pedal 1291 has been pressed. If the close foot pedal 1291 has not been pressed (NO), the control unit 21 transitions the process to step S88.

If the close foot pedal 1291 is pressed in step S85 (YES), the control unit 21 determines in step S86 whether the descent speed of the upper table 121 is 0 or not. If the descent speed of the upper table 121 is 0, this means that the upper table 121 is not descending. The control unit 21 can determine whether the descent speed of the upper table 121 is 0 or not by acquiring the descent speed of the upper table 121 from the NC device 11. If the descent speed of the upper table 121 is not 0 (NO), the control unit 21 transitions the process to step S88.

If the lowering speed of the upper table 121 is 0 in step S86 (YES), the control unit 21 determines in step S87 that the safety confirmation work is complete, and transitions the process to step S109 in FIG. 7A.

In step S88, the control unit 21 determines whether or not an operation to end the safety confirmation work has been performed by pressing the end button. If an operation to end the safety confirmation work has not been performed (NO), the control unit 21 returns the process to step S82 and repeats the processes from step S82 onwards. If an operation to end the safety confirmation work has been performed (YES), the control unit 21 determines in step S89 that the safety confirmation work is incomplete and transitions the process to step S109 in FIG. 7A. In step S109, the control unit 21 records the work status of the safety confirmation work completed or incomplete in the control unit 21, for example, and transitions the process to step S112 in FIG. 7B.

On the other hand, in FIG. 7A, if the operator has not received safety training in step S107 (NO), the control unit 21 displays a message M110 as shown in FIG. 11 on the display unit 22 in step S110, and determines in step S111 whether an operation to continue work has been performed. As an example, the message M110 includes the text "End machine operation or change operator. Have you changed operator?" and a selection button B110 operated by the touch pad 221 to select "Yes" or "No."

If the worker is changed and the new worker touches "Yes" on the selection button B110, the control unit 21 determines in step S111 that an operation to continue the work has been performed (YES), and returns the process to step S105. If the first worker touches "No" on the selection button B110 without changing the worker, the control unit 21 determines in step S111 that an operation to continue the work has not been performed (NO), and ends the process.

In FIG. 7B, the control unit 21 determines in step S112 whether the safety check work has been performed reliably. At least the state in which the work status of the safety check work completion is recorded in the control unit 21 is the state in which the safety check work has been performed reliably. The control unit 21 may add to the conditions for determining whether the safety check work has been performed reliably whether it has determined that the safety check work instruction video has been viewed based on gaze information indicating the worker's gaze or the detection result of the worker's face detected by the gaze detection unit 24 while the safety check work instruction video is being displayed on the display unit 22.

The control unit 21 determines that the safety check work instruction video has been viewed if the proportion of the time during which the worker's gaze is directed toward the display unit 22 relative to the total playback time of the safety check work instruction video file 316 is equal to or greater than a predetermined proportion. Alternatively, the control unit 21 determines that the safety check work instruction video has been viewed if the proportion of the time during which the worker's face is detected relative to the total playback time of the safety check work instruction video file 316 is equal to or greater than a predetermined proportion.

If the safety check work has been reliably performed in step S112 (YES), the NC device 11 permits the machining operation of the press brake main body 12PB in step S113 according to instructions from the control unit 21. In step S114, the NC device 11 determines whether the close foot pedal 1291 has been pressed. If the close foot pedal 1291 has not been pressed (NO), the NC device 11 repeats the process of step S114. If the close foot pedal 1291 has been pressed (YES), the NC device 11 performs actual machining of the workpiece in step S115 and transitions to the process of step S116.

In step S116, the NC unit 11 determines whether or not to continue machining. If machining is to be continued (YES), then in step S122, the NC unit 11 determines whether or not to replace the dies (punch Tp and die Td) and machine another product. If another product is not to be machined (NO), the NC unit 11 repeats the processing from step S113 onwards. If another product is to be machined (YES), the NC unit 11 repeats the processing from step S102 onwards. If machining is not to be continued (NO), the NC unit 11 ends the processing.

On the other hand, if the safety confirmation work has not been performed reliably in step S112 (NO), the control unit 21 displays a message M117 as shown in FIG. 12 on the display unit 22 in step S117, and determines in step S118 whether an operation to perform the safety confirmation work again has been performed. As an example, the message M117 includes the text "Performance of the safety confirmation work cannot be confirmed. Do you want to perform the safety confirmation work again?" and a selection button B117 operated by the touch pad 221 to select "Yes" or "No."

If the control unit 21 has recorded a work status in which the safety confirmation work is not completed, the control unit 21 determines in step S112 that the safety confirmation work has not been performed reliably. Even if the control unit 21 has recorded a work status in which the safety confirmation work is completed, the control unit 21 may determine in step S112 that the safety confirmation work has not been performed reliably if it determines that the safety confirmation work instruction video has not actually been viewed based on the gaze information indicating the worker's gaze detected by the gaze detection unit 24 or the detection result of the worker's face.

If the worker touches "Yes" on the selection button B117 of the message M117, the control unit 21 determines that an operation to perform the safety check work again has been performed in step S118 (YES), and returns the process to step S108. If the worker touches "No" on the selection button B117 of the message M117, the control unit 21 determines that an operation to perform the safety check work again has not been performed in step S118 (NO), and moves the process to step S119. In step S119, the NC device 11, following instructions from the control unit 21, does not permit the machining operation of the press brake main body 12PB.

Then, in step S120, the control unit 21 displays a message M120 as shown in FIG. 13 on the display unit 22, and in step S121, determines whether an operation to continue the work has been performed. As an example, the message M120 includes the text "End machine operation or change the operator. Have you changed the operator?" and a selection button B120 operated by the touch pad 221 to select "Yes" or "No."

If the worker is changed and the new worker touches "Yes" on the selection button B120, the control unit 21 determines in step S121 that an operation to continue the work has been performed (YES), and returns the process to step S105. If the first worker touches "No" on the selection button B120 without changing the worker, the control unit 21 determines in step S121 that an operation to continue the work has not been performed (NO), and ends the process.

Using the flowchart shown in FIG. 14, the processing executed by the NC device 11 or the control unit 21 when the laser processing machine cuts a workpiece will be described, taking as an example the case where the machine tool 100 is a laser processing machine. In the case of the laser processing machine, it is assumed that the video file does not include a safety check operation instruction video file, and that no safety check operation is set that the operator should perform before operating the laser processing machine.

In FIG. 14, when the power supply of the laser processing machine is turned on and processing is started, the NC device 11 returns the processing machine body of the laser processing machine, which corresponds to the machine tool body 12, to the origin in step S201. In step S202, the NC device 11 reads a processing program newly created by the processing program creation device 40 or an existing processing program stored in the processing program database 50.

In step S203, the worker prepares the workpiece, which is the sheet metal W to be processed. In step S204, the worker presses down the clamp foot pedal provided on the processing machine body to fix the workpiece placed on the table so that it does not move. In step S205, the control unit 21 recognizes the worker based on the image of the worker captured by the camera 23. In step S206, the control unit 21 queries the NC device 11 about the safety training attendance history. The NC device 11 supplies the safety training attendance history of the recognized worker to the control unit 21 from the safety training attendance history 32 stored in the server 30.

In step S207, the control unit 21 determines whether the worker has received safety training. There are, for example, three video files as safety training video files that the worker should receive in advance in order to safely operate the laser processing machine. The first video file is a video file that explains warnings or precautions regarding the overall safety of the laser processing machine. The second video file is a video file that explains the need to clean the dust box of the dust collection device and how to clean it. The third video file is a video file that explains the need to clean the scrap box and how to clean it. The control unit 21 may determine that the worker has received safety training if the worker has viewed all three video files.

If the worker has received safety training in step S207 (YES), the NC device 11 permits the laser processing machine (machine body) to perform processing operations in step S208 in accordance with instructions from the control unit 21. The NC device 11 opens the laser shutter provided between the laser oscillator and the processing head in step S209, and performs actual processing of the workpiece in step S210 to end the process.

On the other hand, if it is determined in step S207 that the worker has not received safety training (NO), the control unit 21 in step S211 displays a message M211 as shown in FIG. 15 on the display unit 22, and in step S212 determines whether an operation to continue work has been performed. As an example, the message M212 includes the text "End machine operation or change the worker. Have you changed the worker?" and a selection button B211 operated by the touch pad 221 to select "Yes" or "No."

If the operator is changed and the new operator touches "Yes" on the selection button B211, the control unit 21 determines in step S212 that an operation to continue the work has been performed (YES) and returns the process to step S205. If the first operator touches "No" on the selection button B211 without changing operators, the control unit 21 determines in step S212 that an operation to continue the work has not been performed (NO) and moves the process to step S213. In step S213, the NC device 11, following instructions from the control unit 21, does not permit the laser processing machine (machine body) to perform processing operations.

Then, in step S214, the control unit 21 displays a message M214 as shown in FIG. 16 on the display unit 22, and ends the process. As an example, the message M214 includes the text "Attendance of safety training could not be confirmed. Machine operation will be terminated."

As described above, the machine tool 100 and its control method are configured as follows. The NC device 11 or the control unit 21, or the NC device 11 and the control unit 21, are control devices that control the machine tool 100.

The control device identifies the worker who operates the operation unit such as the operation button 25. The control device checks the safety education attendance history 32, which indicates whether the identified worker has taken the safety education that should be taken in advance in order to safely operate the machine tool main body 12. The control device determines whether to permit or not permit the machining operation of the workpiece by the machine tool main body 12, which is executed by the worker operating the operation unit, according to at least the safety education attendance history 32 of the confirmed worker.

The machine tool 100 and its control method can make the operation of the machine tool 100 different depending on whether an operator who has not received safety training operates the machine tool 100 or an operator who has received safety training operates the machine tool 100. Specifically, even if an operator who has not received safety training operates the machine tool 100 to machine a workpiece, the machine tool 100 will not be able to machine the workpiece or the machining of the workpiece will be limited. If an operator who has received safety training operates the machine tool 100 to machine a workpiece, the machine tool 100 can machine the workpiece. Therefore, safety when using the machine tool 100 can be improved.

If the control device identifies the worker by comparing the worker's face captured by the camera 23 with each facial image in the worker information file 270, the worker operating the operation unit can be identified almost reliably. In order to prevent a worker who has received safety training from being replaced by a worker who has not received safety training while the machine tool 100 is being operated, it is preferable for the control device to identify the worker by face recognition at all times or at specified intervals.

The control device may manage whether or not a worker has received safety training as follows: The control device displays a safety training video on the display unit 22. The control device determines whether or not the worker has viewed the safety training video displayed on the display unit 22. If the control device determines that the worker has viewed the safety training video, it records in the safety training attendance history 32 that the worker has received safety training. Whether or not the worker has viewed the safety training video displayed on the display unit 22 may be based on the worker's line of sight detected by the line of sight detection unit 24, or may be based on detection of the worker's face from the captured image generated by the camera 23.

If the machine tool 100 is a press brake 100PB, the safety check work instruction video of the safety check work instruction video file 316 is displayed on the display unit 22, and the worker is requested to perform the safety check work to check for any abnormalities in the press brake main body 12PB. In such a case, the control device permits the machine tool main body 12 to perform machining operations on the workpiece if the worker has received safety training and performs the safety check work. The control device does not permit the machine tool main body 12 to perform machining operations on the workpiece, even if the worker has received safety training, if the worker does not perform the safety check work.

In this way, any malfunctions or abnormalities in the machine tool 100 can be detected in advance, further improving safety when using the machine tool 100.

Even if the worker has performed a safety check operation, if the control device determines that the worker has not viewed the safety check work instruction video displayed on the display unit 22, the control device may not permit the machining operation of the workpiece. In this way, the worker's awareness of safety can be improved, and safety when using the machine tool 100 can be further improved. In this case, too, whether or not the worker has viewed the safety check work instruction video displayed on the display unit 22 may be based on the worker's line of sight detected by the line of sight detection unit 24, or may be based on detection of the worker's face from the captured image generated by the camera 23.

A worker (administrator) with a worker ID of 0006 and a value of 1 set in the management authority shown in FIG. 3 can operate the operation button 25 to display a safety training attendance history list image 33, for example, as shown in FIG. 17, on the display unit 22. The control unit 21 generates the safety training attendance history list image 33 based on the safety training attendance history 32 read by the NC device 11 from the server 30 and the worker information file 270 stored in the non-volatile memory 27.

In the safety training attendance history list image 33 shown in FIG. 17, the worker name 331 and face image 332 of each worker are associated with a bar graph 333 indicating the safety training video files #1 to #5 that the worker has attended. The worker name 331 and face image 332 of each worker are obtained from the worker information file 270 shown in FIG. 3. The bar graph 333 is created based on the safety training attendance history 32 shown in FIG. 5.

The administrator can check the safety training attendance history list image 33 displayed on the display unit 22 and select an operator to use the machine tool 100 to machine a workpiece. For example, when machining a workpiece that is relatively easy to machine, the operator is permitted to operate the machine tool 100 if the operator has already completed safety training video files #1 to #3. In addition, when machining a workpiece that is relatively difficult to machine, the operator is not permitted to operate the machine tool 100 unless the operator has completed all safety training video files #1 to #5. In such a case, the administrator can check the safety training attendance history list image 33 and select an operator according to the difficulty of machining the workpiece.

The NC device 11 can determine the difficulty of machining the workpiece using the machining program. When the control unit 21 determines in step S107 or S207 whether the worker has received safety training, it can receive the result of the determination of the difficulty of the machining from the NC device 11 and vary the number of safety training video files for which machining operations are permitted.

The present invention is not limited to one or more of the embodiments described above, and various modifications are possible without departing from the gist of the present invention. The NC device 11 or the control unit 21 may generate an alarm when an operator who has not received safety training attempts to operate the operation panel 20 to machine a workpiece. The NC device 11 or the control unit 21 may allow only specific operators to deactivate the alarm. The specific operator may be an operator who has received safety training, or may be a manager.

This application claims priority to Patent Application No. 2023-082812, filed with the Japan Patent Office on May 19, 2023, the entire disclosure of which is incorporated herein by reference.

Claims (10)

A machine tool body for machining a workpiece;
An NC device that controls the machine tool body;
an operation panel having an operation unit operated by an operator to machine the workpiece by the machine tool body, the operation of the operation unit by the operator being received by the NC device or a control unit connected to the NC device;
Equipped with
The NC device or the control unit is
Identifying the worker who operates the operation unit;
confirming a safety training attendance history indicating whether or not the specified operator has attended a safety training course that should be attended in advance in order to safely operate the machine tool body;
A machine tool that determines whether to permit or not permit the machining operation of the workpiece by the machine tool main body, which is executed by the operator operating the operation unit, based on at least the confirmed safety education attendance history of the operator. The operation panel further includes a camera for photographing the worker,
The machine tool according to claim 1, wherein the NC device or the control unit identifies the worker by comparing the face of the worker photographed by the camera with each facial image in a worker information file in which facial images of one or more workers are stored. The operation panel further includes a display unit,
The NC device or the control unit is
A safety training video, which is a video for the safety training, is displayed on the display unit;
determining whether the worker has viewed the safety training video displayed on the display unit;
The machine tool according to claim 1 or 2, wherein if it is determined that the worker has viewed the safety training video, it is recorded in the safety training attendance history that the worker has attended the safety training. The operation panel further includes a display unit,
The NC device or the control unit is
displaying on the display unit a safety confirmation work instruction video instructing the operator to perform a safety confirmation work that should be performed before the operator operates the machine tool body;
If it is determined based on the operator's safety training attendance history that the operator has attended the safety training and has performed the safety confirmation work, permitting the machine tool body to perform a machining operation on the workpiece;
The machine tool according to claim 1 or 2, wherein even if the operator has taken the safety education based on the operator's safety education attendance history, if the operator does not perform the safety confirmation work, the machining operation of the workpiece by the machine tool body is not permitted. The NC device or the control unit is
determining whether the worker has viewed the safety confirmation work instruction video displayed on the display unit;
The machine tool according to claim 4, wherein if it is determined that the operator has viewed the safety check work instruction video, the machining operation of the workpiece by the machine tool body is permitted, and if it is not determined that the operator has viewed the safety check work instruction video, the machining operation of the workpiece by the machine tool body is not permitted. A control device provided in a machine tool,
Identifying an operator who operates an operation unit that is operated to process a workpiece by the machine tool;
checking a safety training attendance history indicating whether the identified operator has attended a safety training course that should be attended in advance in order to safely operate the machine tool;
A machine tool control method which determines whether to permit or not permit the machining operation of the workpiece by the machine tool, which is executed by the operator operating the operation unit, based on at least the confirmed safety education attendance history of the operator. The method for controlling a machine tool according to claim 6, wherein the control device identifies the worker by comparing the face of the worker captured by the camera with each facial image in a worker information file in which one or more facial images of the workers are stored. The control device includes:
A safety training video is displayed on a display unit, the safety training video being a video for the safety training;
determining whether the worker has viewed the safety training video displayed on the display unit;
8. The method for controlling a machine tool according to claim 6, further comprising the step of: recording, in the safety training attendance history, that the worker has attended the safety training, if it is determined that the worker has watched the safety training video. The control device includes:
when a machining operation of the workpiece by the machine tool is permitted as a result of checking the safety education attendance history of the worker, a safety confirmation work instruction video is displayed on a display unit to instruct the worker to perform a safety confirmation work that should be performed before operating the machine tool;
If the operator has taken the safety training based on the operator's safety training attendance history and has performed the safety confirmation work, permitting the machine tool to perform a machining operation on the workpiece;
The method for controlling a machine tool according to claim 6 or 7, further comprising the step of: disallowing the machining operation of the workpiece by the machine tool if the operator does not perform the safety confirmation work, even if the operator has taken the safety education based on the operator's safety education attendance history. The control device includes:
determining whether the worker has viewed the safety confirmation work instruction video displayed on the display unit;
The machine tool control method of claim 9, further comprising the steps of: permitting the machine tool to perform machining of the workpiece if it is determined that the operator has viewed the safety check work instruction video; and not permitting the machine tool to perform machining of the workpiece if it is not determined that the operator has viewed the safety check work instruction video.

Images