Laser machining apparatus, method for setting machining conditions, and control device for laser machining apparatus

A moving mechanism relatively moves a machining head emitting a laser beam, with respect to a sheet metal along a surface of the sheet metal. A beam vibrating mechanism vibrates the laser beam for irradiation on the sheet metal, while the machining head is relatively moved by the moving mechanism. A machining condition setting section sets pattern selection information to select a vibration pattern of the laser beam by the beam vibrating mechanism, and a parameter to determine a vibrating way in the vibration pattern, in accordance with machining conditions specified for each machining command to machine the sheet metal in a machining program generated to machine the sheet metal, and including a machining velocity of the sheet metal associated with relative movement of the machining head by the moving mechanism.

TECHNICAL FIELD

The present disclosure relates to a laser machining apparatus, a method for setting machining conditions, and a control device for the laser machining apparatus.

BACKGROUND ART

Laser machining apparatuses that cut sheet metals by laser beams emitted from laser oscillators, and produce products having predetermined shapes are widely used. In Non-Patent Literature 1, it is described that a sheet metal is cut while vibrating a laser beam in a predetermined vibration pattern.

CITATION LIST

Patent Literature

Non-Patent Literature 1: January 2017, the FABRICATOR 67, Shaping the Beam for the Best Cut

SUMMARY

When a sheet metal is cut by a laser machining apparatus, it is necessary to appropriately select a vibration pattern of a laser beam in accordance with machining conditions of the sheet metal. An object of one or more embodiments is to provide a laser machining apparatus, a method for setting machining conditions, and a control device for the laser machining apparatus that allow for appropriate selection of a vibration pattern of a laser beam in accordance with machining conditions of a sheet metal, when the laser machining apparatus cuts the sheet metal.

According to a first aspect of one or more embodiments, a laser machining apparatus is provided, the laser machining apparatus including a moving mechanism configured to relatively move a machining head emitting a laser beam, with respect to a sheet metal along a surface of the sheet metal, a beam vibrating mechanism configured to vibrate the laser beam for irradiation on the sheet metal, while the machining head is relatively moved by the moving mechanism, and a machining condition setting section configured to set pattern selection information to select a vibration pattern of the laser beam by the beam vibrating mechanism, and a parameter to determine a way of vibration in the vibration pattern, in accordance with machining conditions specified for each machining command to machine the sheet metal in a machining program generated to machine the sheet metal, and including a machining velocity of the sheet metal associated with relative movement of the machining head by the moving mechanism.

According to a second aspect of one or more embodiments, a method for setting machining conditions is provided, the method for setting the machining conditions including reading a machining condition file from a storage section, machining conditions when machining a sheet metal being set in the machining condition file in correspondence to each machining condition number of a plurality of machining condition numbers, displaying, on a display, at least the plurality of machining condition numbers in the read machining condition file, and setting pattern selection information to select a vibration pattern of a laser beam for irradiation on the sheet metal, and a parameter to determine a way of vibration in the vibration pattern, in correspondence to each machining condition number of the plurality of machining condition numbers displayed on the display.

According to a third aspect of one or more embodiments, a control device for a laser machining apparatus is provided, the control device being configured to control the laser machining apparatus including a moving mechanism configured to relatively move a machining head emitting a laser beam, with respect to a sheet metal along a surface of the sheet metal, and a beam vibrating mechanism configured to vibrate the laser beam for irradiation on the sheet metal, while the machining head is relatively moved by the moving mechanism, the control device being configured to read, from a machining program database, a machining program generated to machine the sheet metal and including a command to select a machining condition file, and read, out of a plurality of machining condition files stored in a machining condition database, a machining condition file selected based on the command to select the machining condition file, the command being included in the read machining program, the machining condition file including a machining condition number specified for each machining command to machine the sheet metal in the machining program, velocity data set in correspondence to each machining condition number, and indicating a machining velocity of the sheet metal associated with relative movement of the machining head by the moving mechanism, pattern selection information set in correspondence to each machining condition number, to select a vibration pattern of the laser beam by the beam vibrating mechanism, and a parameter set in correspondence to each machining condition number, to determine a way of vibration in the vibration pattern, the control device being configured to control the moving mechanism to relatively move the machining head at the machining velocity based on the velocity data, for each machining condition number, and control the beam vibrating mechanism to vibrate the laser beam by the way of vibration based on the parameter, in the vibration pattern based on the pattern selection information, for each machining condition number.

According to a laser machining apparatus, a method for setting machining conditions, and a control device for the laser machining apparatus of one or more embodiments, an appropriate vibration pattern can be set in accordance with machining conditions of a sheet metal.

DESCRIPTION OF EMBODIMENT

Hereinafter, a laser machining apparatus, a method for setting machining conditions and a control device for a laser machining apparatus of one or more embodiments will be described with reference to the accompanying drawings. InFIG.1, a laser machining apparatus100includes a laser oscillator10that generates and emits a laser beam, a laser machining unit20, and a process fiber12that transmits the laser beam emitted by the laser oscillator10to the laser machining unit20.

Further, the laser machining apparatus100includes an operation section40, an NC device50, a machining program database60, a machining condition database70, an assist gas supply device80, and a display90. The NC device50is an example of a control device that controls respective parts of the laser machining apparatus100.

As the laser oscillator10, a laser oscillator that amplifies an excitation beam emitted from a laser diode to emit a laser beam of a predetermined wavelength, or a laser oscillator that directly uses a laser beam emitted from a laser diode is preferable. The laser oscillator10is, for example, a solid laser oscillator, a fiber laser oscillator, a disk laser oscillator, or a direct diode laser oscillator (DDL oscillator).

The laser oscillator10emits a laser beam in a band of 1 μm with a wavelength of 900 nm to 1100 nm. Taking a fiber laser oscillator and a DDL oscillator as examples, the fiber laser oscillator emits a laser beam with a wavelength of 1060 nm to 1080 nm, and the DDL oscillator emits a laser beam with a wavelength of 910 mm to 950 nm.

The laser machining unit20has a machining table21where a sheet metal W to be machined is placed, a gate-type X-axis carriage22, a Y-axis carriage23, a collimator unit30fixed to the Y-axis carriage23, and a machining head35. The X-axis carriage22is configured to be movable in an X-axis direction on the machining table21. The Y-axis carriage23is configured to be movable in a Y-axis direction perpendicular to the X-axis on the X-axis carriage22. The X-axis carriage22and the Y-axis carriage23function as a moving mechanism that moves the machining head35in the X-axis direction, the Y-axis direction, or an arbitrary composition direction of an X-axis and a Y-axis, along a surface of the sheet metal W.

Instead of moving the machining head35along the surface of the sheet metal W, a position of the machining head35may be fixed, and the sheet metal W may be configured to move. The laser machining apparatus100can include the moving mechanism that moves the machining head35relatively to the surface of the sheet metal W.

To the machining head35, a nozzle36that has a circular opening36aat a tip end portion, and emits a laser beam from the opening36ais attached. The sheet metal W is irradiated with the laser beam emitted from the opening36aof the nozzle36. The assist gas supply device80supplies nitrogen, oxygen, mixed gas of nitrogen and oxygen, or air as assist gas to the machining head35. At a time of machining the sheet metal W, the assist gas is blown to the sheet metal W from the opening36a. The assist gas discharges molten metal in a kerf width where the sheet metal W is melted.

As illustrated inFIG.2, the collimator unit30includes a collimation lens31that converts a divergent laser beam emitted from the process fiber12into a parallel laser beam (collimated laser beam). Further, the collimator unit30includes a galvano scanner unit32, and a bend mirror33that reflects a laser beam emitted from the galvano scanner unit32toward a lower part in a Z-axis direction perpendicular to the X-axis and the Y-axis. The machining head35includes a focusing lens34that focuses the laser beam reflected by the bend mirror33, and irradiates the sheet metal W.

To adjust a focus position of the laser beam, the focusing lens34is configured to be movable in a direction close to the sheet metal W and a direction away from the sheet metal W, by an unshown drive section and the moving mechanism.

The laser machining apparatus100is centered so that the laser beam emitted from the opening36aof the nozzle36is located at a center of the opening36a. In a regular state, the laser beam is emitted from the center of the opening36a. The galvano scanner unit32functions as a beam vibrating mechanism that vibrates the laser beam that advances in the machining head35and is emitted from the opening36a, in the opening36a. How the galvano scanner unit32vibrates the laser beam will be described later.

The galvano scanner unit32has a scanning mirror321that reflects the laser beam emitted from the collimation lens31, and a drive section322that rotates the scanning mirror321to a predetermined angle. Further, the galvano scanner unit32has a scanning mirror323that reflects the laser beam emitted from the scanning mirror321, and a drive section324that rotates the scanning mirror323to a predetermined angle.

The drive sections322and324can reciprocally vibrate the scanning mirrors321and323within a predetermined angle range respectively based on control by the NC device50. By reciprocally vibrating either one or both of the scanning mirror321and the scanning mirror323, the galvano scanner unit32vibrates the laser beam with which the sheet metal W is irradiated.

The galvano scanner unit32is one example of the beam vibrating mechanism, and the beam vibrating mechanism is not limited to the galvano scanner unit32having a pair of scanning mirrors.

FIG.3illustrates a state where either one or both of the scanning mirror321and the scanning mirror323is or are tilted, and a position of the laser beam with which the sheet metal W is irradiated is displaced. InFIG.3, a fine solid line that is bent by the bend mirror33and passes through the focusing lens34shows an optical axis of the laser beam in the regular state of the laser machining apparatus100.

Note that, in detail, an angle of the optical axis of the laser beam that is incident on the bend mirror33changes by an operation of the galvano scanner unit32located in front of the bend mirror33, and the optical axis deviates from a center of the bend mirror33. InFIG.3, for simplification, incident positions of the laser beams onto the bend mirror33are assumed to be same positions before and after the operation of the galvano scanner unit32.

The optical axis of the laser beam is assumed to be displaced from the position shown by the fine solid line to a position shown by a thick solid line by the action by the galvano scanner unit32. When the laser beam reflected by the bend mirror33is assumed to incline at an angle θ, an irradiation position of the laser beam on the sheet metal W is displaced by a distance Δs. When a focal length of the focusing lens34is EFL (Effective Focal Length), the distance Δs is calculated by EFL×sineθ.

If the galvano scanner unit32inclines the laser beam at the angle θ in an opposite direction to a direction illustrated inFIG.3, the irradiation position of the laser beam on the sheet metal W can be displaced by the distance Δs in an opposite direction to the direction illustrated inFIG.3. The distance Δs is a distance less than a radius of the opening36a, and is preferably a distance less than or equal to a maximum distance when the maximum distance is a distance obtained by subtracting a predetermined margin from the radius of the opening36a.

The NC device50can vibrate the laser beam in a predetermined direction within a surface of the sheet metal W by controlling the drive sections322and324of the galvano scanner unit32. By vibrating the laser beam, it is possible to vibrate a beam spot formed on the surface of the sheet metal W.

The laser machining apparatus100configured as above cuts the sheet metal W with the laser beam emitted from the laser oscillator10and produces a product having a predetermined shape. The laser machining apparatus100locates a focus of the laser beam at any appropriate position on a top surface of the sheet metal W, or within a thickness of the sheet metal W above the top surface by a predetermined distance or below the top surface by a predetermined distance, and cuts the sheet metal while vibrating the laser beam in a predetermined vibration pattern.

A machining program to cut the sheet metal W is stored in the machining program database60. The NC device50reads the machining program from the machining program database60, and selects any machining condition file from a plurality of machining condition files stored in the machining condition database70. The NC device50controls the laser machining apparatus100to cut the sheet metal W based on the read machining program and machining conditions set in the selected machining condition file.

As described later, the laser machining apparatus100is configured to be able to set the vibration pattern of the laser beam in correspondence to each machining condition set in the machining condition file. The display90displays a set item when setting the vibration pattern of the laser beam in accordance with each machining condition, based on the control by the NC device50.

Examples of the vibration pattern in which the NC device50vibrates the laser beam by the galvano scanner unit32will be described with reference toFIG.4AtoFIG.4E. It is assumed that a cutting advancing direction of the sheet metal W is an x-direction and that a direction orthogonal to the x-direction within the surface of the sheet metal W is a y-direction. The vibration pattern is set to each machining condition of the machining condition file stored in the machining condition database70, and the NC device50controls the galvano scanner unit32to vibrate the laser beam in the vibration pattern set to the machining conditions.

FIG.4AtoFIG.4Eillustrate the vibration patterns in a state where the machining head35is not moved in the x-direction to make it easier to understand the vibration pattern.FIG.4Aillustrates a vibration pattern in which a beam spot Bs is vibrated in the x-direction in a groove Wk formed by advancement of the beam spot Bs. The vibration pattern illustrated inFIG.4Ais referred to as a parallel vibration pattern. At this time, a kerf width K1of the groove Wk is substantially a diameter of the beam spot Bs. When a frequency at which the beam spot Bs is vibrated in a direction parallel to the cutting advancing direction is Fx and a frequency at which the beam spot Bs is vibrated in a direction orthogonal to the cutting advancing direction is Fy, the parallel vibration pattern is a vibration pattern in which Fx:Fy is 1:0.

FIG.4Billustrates a vibration pattern in which the beam spot Bs is vibrated in the y-direction. When the beam spot Bs is vibrated in the y-direction, the groove Wk has a kerf width K2larger than the kerf width K1. A vibration pattern illustrated inFIG.4Bis referred to as an orthogonal vibration pattern. The orthogonal vibration pattern is a vibration pattern in which Fx:Fy is 0:1.

FIG.4Cillustrates a vibration pattern in which the beam spot Bs is vibrated so that the beam spot Bs draws a circle. When the beam spot Bs is vibrated in a circular shape, the groove Wk has a kerf width K3larger than the kerf width K1. The vibration pattern illustrated inFIG.4Cis referred to as a circular vibration pattern. The circular vibration pattern is a vibration pattern in which Fx:Fy is 1:1.

FIG.4Dillustrates a vibration pattern in which the beam spot Bs is vibrated so that the beam spot Bs draws alphabet C. When the beam spot Bs is vibrated in a C-shape, the groove Wk has a kerf width K4larger than the kerf width K1. The vibration pattern illustrated inFIG.4Dis referred to as a C-shaped vibration pattern. The C-shaped vibration pattern is a vibration pattern in which Fx:Fy is 2:1 (=1:1/2). Further, a phase difference between Fy and Fx is 1/2π(=90′).

FIG.4Eillustrates a vibration pattern in which the beam spot Bs is vibrated so that the beam spot Bs draws a figure of 8. When the beam spot Bs is vibrated in an 8-shape, the groove Wk has a kerf width K5larger than the kerf width K1. The vibration pattern illustrated inFIG.4Eis referred to as an 8-shaped vibration pattern. The 8-shaped vibration pattern is a vibration pattern in which Fx:Fy is 2:1.

In reality, while the machining head35moves in the cutting advancing direction, the laser beam vibrates. Therefore, the vibration pattern is a vibration pattern obtained by adding a displacement in the cutting advancing direction (the x-direction) to the vibration patterns illustrated inFIG.4AtoFIG.4E. Taking the orthogonal vibration pattern illustrated inFIG.4Bas an example, the beam spot Bs vibrates in the y-direction while moving in the x-direction, and hence, an actual orthogonal vibration pattern is such a vibration pattern as illustrated inFIG.5.

Next, description will be made as to how an appropriate vibration pattern is set in accordance with the machining conditions of the sheet metal W with reference toFIG.6toFIG.10. As illustrated inFIG.6, the NC device50includes, as a functional configuration, an NC control section501, a pattern program generation section502, a pattern program retention section503, a vibration control section504, a moving mechanism control section505, an oscillator control section506, a machining condition setting section507, and a display control section508.

When the operation section40gives an instruction to read the machining program, the NC control section501reads the machining program beforehand generated to cut the sheet metal W and stored in the machining program database60. As an example, the machining program is constituted of a plurality of commands represented in machine control codes as illustrated inFIG.7.

InFIG.7, M102indicates a command to select the machining condition file, and here, as an example, it is commanded to select the machining condition file named C-SUS3.0. M100indicates a command to execute laser machining. A number with alphabet E (E-number) indicates an after-mentioned machining condition number. A command starting with G01 indicates a machining command of linear interpolation to move the laser beam at a moving velocity F on a line connecting a start point and an end point specified with X and Y.

A command starting with G02 indicates a machining command of circular interpolation to move the laser beam at the moving velocity F on a circular arc connecting a start point and an end point. There are a method of identifying a circular arc by specifying a radius of the circular arc and a method of identifying a circular arc by specifying a center of the circular arc, and the former method is shown here.

In the machining condition database70, the machining condition file named C-SUS3.0 illustrated inFIG.8and a plurality of other machining condition files are stored. The machining condition file illustrated inFIG.8indicates a state where an after-mentioned parameter to determine the vibration pattern is not added. The parameter is an element to determine a specific way of vibration in the vibration pattern. First, outline of the machining condition file in the state where the parameter to determine the vibration pattern is not added is as follows.

As illustrated inFIG.8, the machining condition file includes information on a name of the laser oscillator10, the material and thickness of the sheet metal W, a nozzle type, i.e., a type of the nozzle36, a nozzle diameter, i.e., a diameter of the opening36a, and the focal length of the focusing lens34. These pieces of information indicate conditions to be applied in common even if the machining condition with any machining condition number set in the machining condition file is selected. The machining condition file may include the other pieces of information the illustration of which are omitted fromFIG.8.

In the machining condition file, various conditions when machining the sheet metal W are set in correspondence to a plurality of machining condition numbers. Each machining condition number corresponds to the number with alphabet E (the E-number) of the machining program illustrated inFIG.7. InFIG.8, a velocity indicates a machining velocity of the sheet metal W that is the moving velocity of the machining head35(velocity data). Output, frequency and duty indicate a laser output (laser power), a pulse oscillating frequency, and duty of the laser oscillator10, respectively. A gas pressure and gas type indicate the gas pressure and gas type of assist gas to be supplied by the assist gas supply device80, respectively.

A nozzle gap indicates a distance from a tip end of the nozzle36to the top surface of the sheet metal W. A tool radius compensation amount indicates a distance by which the laser beam is displaced from an end portion at a time of scanning the laser beam along the end portion of the product. The tool radius compensation amount is the distance corresponding to a radius of the beam spot Bs. A focus compensation amount indicates a distance by which the focus of the laser beam is displaced upward or downward from a reference position (0.00). Other conditions that are omitted fromFIG.8may be set in correspondence to each machining condition number.

As illustrated inFIG.9, in the machining condition database70, a first parameter to determine each vibration pattern is stored in correspondence to the vibration pattern number to select each vibration pattern. The vibration pattern number is pattern selection information to select the vibration pattern of the laser beam. The first parameter is a parameter to determine a shape of each vibration pattern. Here, a vibration pattern name is indicated in correspondence to each vibration pattern number to facilitate understanding, but it is not necessary to store the vibration pattern name in the machining condition database70.

In the machining condition database70, a frequency ratio of a frequency at which the laser beam is vibrated in the x-direction to a frequency at which the laser beam is vibrated in the y-direction and a phase difference between the vibration in the x-direction and the vibration in the y-direction are set as the first parameters in correspondence to each vibration pattern number.

When the operation section40performs an operation of setting the parameter to determine the vibration pattern, the machining condition setting section507controls the display control section508to display, on the display90, such a setting list as illustrated inFIG.10. As illustrated inFIG.10, the setting list is a list to set a second parameter for each vibration pattern number, the second parameter being set to select the vibration pattern number in correspondence to each E-number, and determine the vibration pattern of each vibration pattern number. The second parameter is the parameter to determine an amplitude and frequency of each vibration pattern, the pattern having the shape determined in accordance with the first parameter.

InFIG.10, Qx indicates a set value to set the amplitude in the x-direction, and Qy indicates a set value to set the amplitude in the y-direction. For example, in the machining conditions of E-number E2, a circular vibration pattern with an amplitude of 90 (μm) in the x-direction, an amplitude of 90 (μm) in the y-direction and a frequency of 3000 (Hz) is set.

It is not necessary to display, in the setting list, all kinds of information corresponding to the machining condition numbers of the machining condition file illustrated inFIG.8. In the setting list, the E-numbers may only be displayed, and the E-numbers may be associated with the vibration pattern numbers and the second parameters.

By operating the operation section40, a manufacturer setting person or serviceman of the laser machining apparatus100can display the setting list illustrated inFIG.10on the display90, to set the vibration pattern number and the second parameter. It is preferable that a user of the laser machining apparatus100cannot perform an operation of displaying, on the display90, set items surrounded with a thick solid line, and cannot see the set items surrounded with the thick solid line. When the user operates the operation section40to display a list of E-numbers on the display90, a list of machining conditions excluding the set items surrounded with the thick solid line may be set to be displayed.

The machining condition file to which the vibration pattern number and the second parameter to determine the vibration pattern as above are added is written into the machining condition database70. The machining condition database70is an example of a storage section that stores the machining condition file to which the vibration pattern number and the second parameter are added. The machining condition file may be stored in another storage section connected to the NC device50.

When the machining program illustrated inFIG.7is supplied to the NC control section501, information in which the first parameter is associated with each vibration pattern number illustrated inFIG.9and the machining condition file named C-SUS3.0 are read from the machining condition database70. The vibration pattern number and the second parameter are added to the machining condition file. The information and the machining condition file illustrated inFIG.9are supplied from the machining condition setting section507to the NC control section501.

The pattern program generation section502generates a pattern program to vibrate the laser beam in the vibration patterns corresponding to all the E-numbers included in the machining program read by the NC control section501. The pattern program is a control code to operate the galvano scanner unit32, and in the program, order (processing) to a computer is described. The pattern program generation section502can generate the pattern program based on the first and second parameters supplied to the NC control section501. The pattern program generated by the pattern program generation section502is supplied to and retained in the pattern program retention section503.

After being commanded to execute the laser machining by the machining program, the NC control section501supplies the vibration pattern number for each E-number to the vibration control section504. The NC control section501extracts, out of the information included in the machining condition file, information on the focal length of the focusing lens34that is required to determine the vibration pattern, and supplies the information to the vibration control section504. It is preferable that in addition to the information on the focal length, the NC control section501extracts information on the focus compensation amount and supplies the information to the vibration control section504. Although not illustrated inFIG.6, the information on the focus compensation amount is also used to control the drive section of the focusing lens34so that the focus position of the laser beam is adjusted. Further, the NC control section501supplies vector information to move the laser beam to the vibration control section504, based on a machining command starting with G01, G02 or the like and given to move the laser beam.

The vibration control section504reads the pattern program corresponding to the vibration pattern number from the pattern program retention section503. The vibration control section504controls the drive sections322and324of the galvano scanner unit32to vibrate the laser beam in the selected vibration pattern and on the set conditions, based on the pattern program, the vector information, and the focal length and focus compensation amount of the focusing lens34.

An offset value indicating a distance by which the laser beam emitted from the opening36aof the nozzle36is offset from the center of the opening36ain at least one of the x-direction and the y-direction may be set in accordance with the machining program or the machining condition file, or by manual setting through the operation section40. In this case, the NC control section501supplies offset values in the x-direction and the y-direction to the vibration control section504.

The moving mechanism including the X-axis carriage22and the Y-axis carriage23(hereinafter, referred to as the moving mechanisms22and23) has drive sections220and230that drive the moving mechanisms22and23, respectively. The moving mechanism control section505controls the drive sections220and230based on the machining command to move the laser beam, and moves the machining head35. The moving mechanism control section505controls the drive sections220and230to move the machining head35, for example, every millisecond. Therefore, the cutting advancing direction in which the sheet metal W is cut with the laser beam is controlled in a control period of 1 ms (a first control period).

The vibration control section504may control the drive sections322and324in a control period shorter than 1 ms, and control the vibration of the laser beam in a control period shorter than 1 ms.FIG.11conceptually illustrates a state where the moving mechanism control section505circularly moves the machining head35(the laser beam) in the control period of 1 ms, based on the machining command starting with G02 (or G03). The vibration control section504controls the vibration of the laser beam, for example, in a control period of 1 ms divided by 100, i.e., 10 μs (a second control period). Thus, the laser beam can be highly precisely vibrated in a pattern set with each vibration pattern every 10 μs.

Note that periods in the first control period and the second control period can be arbitrarily set in circumstances of the NC device50, and motor amplifiers or motors of the moving mechanisms22and23. Further, another control period can be set to a middle between the first control period and the second control period to further subdivide the first control period.

The present invention is not limited to the one or more embodiments described above, and can be variously changed within the range without departing from the summary of the present invention. In the one or more embodiments, the parameter to determine the way of vibration in the vibration pattern is divided into the first parameter and the second parameter, but the way of setting the parameter is arbitrary as long as the specific way of vibration in each vibration pattern can be determined. The functional configuration in the NC device50illustrated inFIG.6may be acquired by executing a computer program stored in a non-temporary storage medium by a central processing unit of the NC device50.

The disclosure of this application relates to the subject described in Japanese Patent Application No. 2018-198278 filed on Oct. 22, 2018, the entire disclosed contents of which are incorporated herein by reference.