WO2019176292A1

WO2019176292A1 - Laser processing machine and laser processing method

Info

Publication number: WO2019176292A1
Application number: PCT/JP2019/001944
Authority: WO
Inventors: 山梨　貴昭; 厚司舟木
Original assignee: 株式会社アマダホールディングス
Priority date: 2018-03-12
Filing date: 2019-01-23
Publication date: 2019-09-19
Also published as: JP6538910B1; JP2019155401A

Abstract

A beam displacement mechanism causes the position of a laser beam, emitted via an opening (36a) of a nozzle (36), to be displaced in the opening (36a). An assist gas supply device (80) supplies an assist gas to a processing head (35) during processing of a metal sheet (W). A control device (NC device 50), when implementing a piercing process outside a product, controls the beam displacement mechanism so that the position of the laser beam in the opening (36a) is displaced from the center of the opening (36a) to a position in a direction away from the product. The control device, when cutting the outline of the product, controls the beam displacement mechanism so that the position of the laser beam in the opening (36a) is displaced from the center of the opening (36a) toward the front in a cutting proceeding direction.

Description

Laser processing machine and laser processing method

The present disclosure relates to a laser processing machine and a laser processing method for processing a sheet metal with a laser beam.

Laser processing machines that manufacture a product having a predetermined shape by cutting a sheet metal with a laser beam emitted from a laser oscillator have become widespread. When a laser beam is emitted from a nozzle to cut a sheet metal, the laser processing machine is configured to spray an assist gas from the nozzle to the sheet metal to discharge molten metal within the kerf width (see Patent Document 1). ).

International Publication No. 2015/156119

When a laser processing machine cuts a sheet metal with a laser beam to produce a product having a predetermined shape, the laser processing machine opens a hole called a piercing with a laser beam at a position outside the sheet metal product. The laser beam machine cuts the sheet metal along the outer shape of the product after performing an approach process of cutting to a predetermined position of the outer shape of the product following the piercing process of piercing the sheet metal with the laser beam.

The laser processing machine performs piercing processing or cuts the sheet metal by irradiating the sheet metal with a laser beam while spraying an assist gas according to the material of the sheet metal on the sheet metal. In the approach processing or cutting along the outer shape of the product, the molten metal melted by the heat of the laser beam is blown off by the assist gas from the already cut groove to the back side of the sheet metal. However, since no groove or hole is formed during the piercing process, the molten metal is blown off to the surface of the sheet metal by the assist gas and adheres around the piercing.

The molten metal that scatters during the piercing process should not adhere to the product side around the piercing. It is desired to reduce the amount of molten metal adhering to the product side around the piercing when performing piercing processing in which the piercing is opened in the sheet metal while spraying the assist gas onto the sheet metal.

The more the consumption of assist gas, the higher the production cost of the product. Therefore, it is desired to reduce the production cost of the product by reducing the consumption amount of the assist gas when the laser processing machine cuts the sheet metal to produce the product.

One or more embodiments can reduce the amount of molten metal that adheres to the product side around the piercing during piercing and reduces the consumption of assist gas when cutting the sheet metal to produce the product. An object of the present invention is to provide a laser processing machine and a laser processing method capable of reducing the manufacturing cost of a product.

According to the first aspect of the one or more embodiments, the processing head having a nozzle that emits a laser beam from an opening attached to the tip thereof, and the surface of the sheet metal that is cut by being irradiated with the laser beam. A moving mechanism for moving the relative position of the processing head, a beam displacement mechanism for displacing the position of the laser beam emitted from the opening in the opening, and spraying the sheet metal from the opening during the processing of the sheet metal An assist gas supply device for supplying an assist gas to the processing head, and a laser emitted from the opening when performing piercing processing for opening a piercing outside a product to be cut from the sheet metal by a laser beam as the processing of the sheet metal The position of the beam in the opening is displaced from the center of the opening to a position away from the product. When cutting the outer shape of the product with a laser beam as processing the sheet metal, the position of the laser beam emitted from the opening is displaced to the front side in the cutting progress direction from the center of the opening. A laser processing machine comprising a control device for controlling the beam displacement mechanism is provided.

According to a second aspect of the one or more embodiments, a nozzle attached to the tip of the processing head when performing piercing to open a piercing outside the product in order to cut the product from the sheet metal with a laser beam The position in the opening of the laser beam emitted from the opening is displaced to a position away from the product from the center of the opening, and assist gas is blown from the opening to the sheet metal during the piercing process. When the molten metal of the sheet metal melted by the heat of the laser beam is blown away in a direction away from the product around the piercing, and the outer shape of the product is cut by the laser beam, the laser beam emitted from the opening The position in the opening is displaced forward from the center of the opening in the cutting progress direction, A laser processing method is provided in which an assist gas is blown to the sheet metal from the opening and the molten metal of the sheet metal melted by heat from a laser beam is discharged from a groove formed around the outer shape of the product when cutting the outer shape of the product. Is done.

According to the laser processing machine and the laser processing method of one or more embodiments, the amount of molten metal adhering to the product side around the piercing can be reduced. Further, when the product is manufactured by cutting the sheet metal, the consumption of the assist gas can be reduced and the manufacturing cost of the product can be reduced.

FIG. 1 is a diagram showing an overall configuration example of a laser processing machine according to one or more embodiments. FIG. 2 is a perspective view illustrating a detailed configuration example of a collimator unit and a processing head in a laser processing machine according to one or more embodiments. FIG. 3 is a diagram for explaining the displacement of the irradiation position of the laser beam on the sheet metal by the beam displacement mechanism. FIG. 4 is a partial plan view showing a state in which a plurality of rectangular products are cut off on a sheet metal. FIG. 5A is a partial plan view showing a relationship between a piercing position and a nozzle position in a normal piercing process. FIG. 5B is a partial plan view showing a relationship between a piercing position and a nozzle position in the piercing process employing the first displacement method. FIG. 5C is a partial plan view showing the relationship between the piercing position and the nozzle position in the piercing process employing the second displacement method. FIG. 6 is a side view showing how the molten metal is scattered when the irradiation position of the laser beam on the metal plate is displaced by the beam displacement mechanism. FIG. 7 is a plan view showing how the molten metal is scattered when the irradiation position of the laser beam on the metal plate is displaced by the beam displacement mechanism. FIG. 8 is a partial plan view showing an example of an adhesion state of spatter when piercing is performed by the laser processing machine and the laser processing method of one or more embodiments. FIG. 9 is a partially broken side view conceptually showing the flow of assist gas when the irradiation position of the laser beam on the metal plate is displaced forward in the cutting progress direction by the beam displacement mechanism. FIG. 10 is a plan view conceptually showing the flow of assist gas when the irradiation position of the laser beam on the metal plate is displaced forward in the cutting progress direction by the beam displacement mechanism. FIG. 11 is a diagram showing a parallel vibration pattern of a laser beam. FIG. 12 is a diagram showing an orthogonal vibration pattern of a laser beam.

Hereinafter, laser processing machines and laser processing methods according to one or more embodiments will be described with reference to the accompanying drawings. In FIG. 1, a laser processing machine 100 includes a laser oscillator 10 that generates and emits a laser beam, a laser processing unit 20, and a process fiber 12 that transmits the laser beam emitted from the laser oscillator 10 to the laser processing unit 20. With.

Further, the laser processing machine 100 includes an operation unit 40, an NC device 50, a processing program database 60, a processing condition database 70, and an assist gas supply device 80. The NC device 50 is an example of a control device that controls each part of the laser processing machine 100.

The laser oscillator 10 is preferably a laser oscillator that amplifies excitation light emitted from a laser diode and emits a laser beam having a predetermined wavelength, or a laser oscillator that directly uses a laser beam emitted from a laser diode. The laser oscillator 10 is, for example, a solid laser oscillator, a fiber laser oscillator, a disk laser oscillator, or a direct diode laser oscillator (DDL oscillator).

The laser oscillator 10 emits a 1 μm band laser beam having 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 having a wavelength of 1060 nm to 1080 nm, and the DDL oscillator emits a laser beam having a wavelength of 910 nm to 950 nm.

The laser processing unit 20 includes a processing table 21 on which a sheet metal W to be processed is placed, a portal X-axis carriage 22, a Y-axis carriage 23, a collimator unit 30 fixed to the Y-axis carriage 23, and a processing head 35. Have The sheet metal W may be stainless steel or mild steel, and the material is not limited.

The X-axis carriage 22 is configured to be movable on the processing table 21 in the X-axis direction. The Y-axis carriage 23 is configured to be movable in the Y-axis direction perpendicular to the X-axis on the X-axis carriage 22. The X-axis carriage 22 and the Y-axis carriage 23 serve as a moving mechanism that moves the machining head 35 along the surface of the sheet metal W in the X-axis direction, the Y-axis direction, or any combination direction of the X-axis and the Y-axis. Function.

Instead of moving the machining head 35 along the surface of the sheet metal W, the position of the machining head 35 may be fixed and the sheet metal W may be moved. The laser processing machine 100 only needs to include a moving mechanism that moves the processing head 35 relative to the surface of the sheet metal W.

The processing head 35 is provided with a nozzle 36 having a circular opening 36a at the tip and emitting a laser beam from the opening 36a. The laser beam emitted from the opening 36 a of the nozzle 36 is applied to the sheet metal W. The assist gas supply device 80 supplies nitrogen to the processing head 35 as the assist gas when the sheet metal W is stainless steel and when the sheet metal W is mild steel. At the time of processing the sheet metal W, the assist gas is blown onto the sheet metal W through the opening 36a. In any steel type, a mixed gas containing nitrogen and oxygen as components can be used as an assist gas depending on the processing intention.

In the piercing process, the assist gas blows away the molten metal in which the sheet metal W is melted, and in the approach process or the cutting of the outer shape of the product, the assist gas discharges the molten metal within the kerf width. The cutting of the outer shape of the product includes a case where the outer periphery of the product is cut and a case where the inner periphery of the product is cut to form an opening inside the product. Hereinafter, the case where the product outer shape is the outer periphery of the product is taken as an example.

As shown in FIG. 2, the collimator unit 30 includes a collimation lens 31 that converts a diverging laser beam emitted from the process fiber 12 into parallel light (collimated light). The collimator unit 30 includes a galvano scanner unit 32 and a bend mirror 33 that reflects the laser beam emitted from the galvano scanner unit 32 downward in the Z-axis direction perpendicular to the X-axis and the Y-axis. The processing head 35 includes a focusing lens 34 that focuses the laser beam reflected by the bend mirror 33 and irradiates the sheet metal W.

The focusing lens 34 can be adjusted in position in the optical axis direction. The focusing lens 34 functions as a focusing point adjustment mechanism that adjusts the focusing point of the laser beam irradiated onto the sheet metal W.

The laser beam machine 100 is centered so that the laser beam emitted from the opening 36a of the nozzle 36 is positioned at the center of the opening 36a. In the reference state, the laser beam is emitted from the center of the opening 36a. The galvano scanner unit 32 functions as a beam displacement mechanism that moves through the processing head 35 and displaces the position of the laser beam emitted from the opening 36a in the opening 36a. As a result, the galvano scanner unit 32 displaces the position at which the laser beam is applied to the sheet metal W to a position separated by a predetermined distance from a position directly below the center of the opening 36a.

The galvano scanner unit 32 includes a scan mirror 321 that reflects the laser beam emitted from the collimation lens 31 and a drive unit 322 that rotates the scan mirror 321 at a predetermined angle. The galvano scanner unit 32 includes a scan mirror 323 that reflects the laser beam emitted from the scan mirror 321 and a drive unit 324 that rotates the scan mirror 323 at a predetermined angle.

The driving

units

322 and 324 can reciprocate the scan mirrors 321 and 323 in a predetermined angle range based on the control by the NC device 50, respectively. The galvano scanner unit 32 can vibrate the laser beam applied to the sheet metal W by reciprocally vibrating one or both of the scan mirror 321 and the scan mirror 323. In other words, the NC apparatus 50 can also cause the galvano scanner unit 32 to function as a beam vibration mechanism that vibrates the laser beam emitted from the opening 36a while traveling in the machining head 35.

The galvano scanner unit 32 is an example of a beam displacement mechanism and a beam vibration mechanism, and the beam displacement mechanism and the beam vibration mechanism are not limited to the galvano scanner unit 32.

FIG. 3 shows a state in which one or both of the scan mirror 321 and the scan mirror 323 is tilted and the position of the laser beam applied to the sheet metal W is displaced. In FIG. 3, a thin solid line bent by the bend mirror 33 and passing through the focusing lens 34 indicates the optical axis of the laser beam when the laser processing machine 100 is in the reference state.

More specifically, the angle of the optical axis of the laser beam incident on the bend mirror 33 is changed by the operation of the galvano scanner unit 32 located in front of the bend mirror 33, and the optical axis is changed from the center of the bend mirror 33. Come off. In FIG. 3, for the sake of simplicity, the incident position of the laser beam on the bend mirror 33 is the same before and after the operation of the galvano scanner unit 32.

Suppose that the optical axis of the laser beam is displaced from the position indicated by the thin solid line to the position indicated by the thick solid line by the action of the galvano scanner unit 32. If the laser beam reflected by the bend mirror 33 is tilted at an angle θ, the irradiation position of the laser beam on the sheet metal W is displaced by a distance Δs. When the focal length of the focusing lens 34 is EFL (EffectiveEFocal Length), the distance Δs is calculated as EFL × sin θ.

When the galvano scanner unit 32 tilts the laser beam by an angle θ in the direction opposite to the direction shown in FIG. 3, the irradiation position of the laser beam on the sheet metal W is displaced by a distance Δs in the direction opposite to the direction shown in FIG. be able to. The distance Δs is a distance less than the radius of the opening 36a, and is preferably a distance equal to or less than the maximum distance with a distance obtained by subtracting a predetermined margin from the radius of the opening 36a as a maximum distance.

The NC device 50 can displace the position at which the sheet metal W is irradiated with the laser beam by controlling the

drive units

322 and 324 of the galvano scanner unit 32. The NC device 50 can also vibrate the laser beam in a predetermined direction within the surface of the sheet metal W. By oscillating the laser beam, the beam spot formed on the surface of the sheet metal W can be oscillated.

As shown in FIG. 4, a case is considered in which a plurality of rectangular products 200 are cut off on a sheet metal W and the laser processing machine 100 cuts each product 200. The piercing process is performed at the position shown in FIG. 4 to open the piercing 201. When the piercing 201 is opened, the approach 202 is cut, and the sheet metal W is cut from the end of the approach 202 on the product 200 side along the outer periphery of the product 200. Suppose a program has been created. The machining program is stored in the machining program database 60.

The NC device 50 reads the machining program from the machining program database 60 and selects one of a plurality of machining conditions stored in the machining condition database 70. The NC device 50 controls the laser processing machine 100 so as to process the sheet metal W based on the read processing program and the selected processing conditions.

As shown in FIG. 5A, the position at which the piercing 201 is opened by piercing by the machining program is set to the coordinates (X1, Y1) on the sheet metal W. If the laser beam is emitted from the center of the opening 36a, the NC device 50 may position the machining head 35 so that the center of the opening 36a is located at the coordinates (X1, Y1). If the center of the opening 36a is located at the coordinates (X1, Y1), the center of the opening 36a is located immediately above the position where the piercing 201 is opened.

If the thickness of the sheet metal W is thick, the time until the piercing 201 is formed becomes long, and a phenomenon may occur in which the melted portion just below the center of the opening 36a moves slightly in the surface direction. Then, the amount of molten metal is not uniform in the circumferential direction and is biased in a predetermined direction.

As shown in FIG. 5A, when the center of the opening 36a is positioned immediately above the position where the piercing 201 is opened and the assist gas is blown onto the sheet metal W, more molten metal is scattered in the direction in which the amount of molten metal is biased. . Both the molten metal that scatters and the deposited metal mass that adheres to the sheet metal W and solidifies may be referred to as sputtering, but in one or more embodiments, the deposited metal mass is referred to as sputtering. Since the direction in which the amount of molten metal is biased is random, the direction in which a large amount of molten metal is scattered and a large amount of spatter adheres is random.

In one or more embodiments, the first displacement method shown in FIG. 5B or the second displacement method shown in FIG. 5C is used to control the direction in which the molten metal Wmelt scatters and spatter adheres. By adopting, the position of the laser beam in the opening 36 a is displaced to a position away from the product 200 from the center of the opening 36 a.

In the first displacement method, as shown in FIG. 5B, the NC device 50 is located immediately above the position where the center of the opening 36a is displaced to the product 200 side on the approach 202 from the coordinates (X1, Y1). As described above, the machining head 35 is displaced toward the product 200 along the approach 202. In addition to this, the NC apparatus 50 changes the angle of the

scan mirror

321 or 323 in the galvano scanner unit 32 so that the position where the laser beam is irradiated onto the sheet metal W becomes the coordinates (X1, Y1). As a result, the position at which the laser beam is applied to the sheet metal W is not directly under the center of the opening 36 a but is displaced to the side away from the product 200.

In the second displacement method, as shown in FIG. 5C, the NC device 50 positions the machining head 35 so that the center of the opening 36a is located at the coordinates (X1, Y1). In addition, the NC apparatus 50 is configured so that the position where the laser beam is irradiated onto the sheet metal W is positioned on the extension line of the approach 202 on the side farther from the product 200 than the coordinates (X1, Y1). The angle of the

scan mirror

321 or 323 in the unit 32 is changed. As a result, the position at which the laser beam is applied to the sheet metal W is not directly under the center of the opening 36 a but is displaced to the side away from the product 200.

When the second displacement method shown in FIG. 5C is adopted, it is necessary for the NC device 50 to modify the machining program to change the position where the piercing 201 is opened and to extend the approach 202. In some cases, interference between the peripheral cutting line of adjacent products and the piercing position must be taken into account, which may complicate the processing. Therefore, the first displacement method is preferable to the second displacement method.

FIG. 6 conceptually shows the operation of opening the piercing on the sheet metal W by the laser beam displaced outward from the center 36 ctr of the opening 36 a when viewed from the side surface direction of the machining head 35, and FIG. The state which looked at the sheet metal W from FIG. When piercing the sheet metal W, the NC device 50 raises the machining head 35 so that the nozzle 36 is separated from the sheet metal W. Therefore, as shown in FIG. 6, the beam waist of the laser beam indicated by the alternate long and short dash line is located above the sheet metal W.

As shown in FIG. 6 and FIG. 7, although the assist gas AG is sprayed uniformly on the sheet metal W in the circumferential direction, the laser beam irradiated to the sheet metal W is displaced, so the molten metal Wmelt is displaced by the laser beam. Splash in the direction you did. Even if the amount of the molten metal Wmelt is biased toward the product 200, the distance Δs for displacing the laser beam on the metal plate W is much larger than the distance at which the amount of the molten metal Wmelt is biased. Spatters in the displaced direction.

If the position where the laser beam is irradiated onto the sheet metal W is displaced from a position directly under the center 36 ctr of the opening 36 a to a position away from the product 200, the molten metal Wmelt is scattered in the direction in which the laser beam is displaced. Wmelt scatters away from the product 200.

Therefore, according to the laser processing machine 100 of one or more embodiments and the laser processing method executed by the laser processing machine 100, as shown in FIG. It is possible to control so that the spatter Sp is attached to the opposite side and hardly sputtered Sp is attached to the product 200 side. Therefore, since the piercing 201 can be opened near the product 200, the interval D between the adjacent products 200 shown in FIG. 4 can be reduced. As a result, according to the laser processing machine 100 and the laser processing method of one or more embodiments, the yield can be improved.

In addition, according to the laser processing machine 100 and the laser processing method of one or more embodiments, since the spatter Sp hardly adheres to the approach 202, the approach processing is stabilized, and the possibility of causing processing defects can be reduced. it can.

5B and 5C, the direction in which the position of the laser beam applied to the sheet metal W is displaced is the direction away from the product 200 along the approach 202, but is not limited to the direction along the approach 202. If the direction is away from the product 200, the direction may not be along the approach 202.

Next, a method for reducing the production cost of the product by reducing the consumption amount of the assist gas in the laser processing machine 100 will be described. When the laser processing machine 100 performs the piercing process as described above and opens the piercing 201, the laser processing machine 100 cuts the approach 202 as follows, and from the end of the approach 202 on the product 200 side to the outer periphery of the product 200. The sheet metal W is cut along.

As shown in FIG. 9 or FIG. 10, at the time of approach processing or cutting of the outer periphery of the product, the NC device 50 cuts the laser beam (beam spot Bs shown in FIG. 10) from the center 36ctr of the opening 36a by the galvano scanner unit 32. Displace forward in the direction of travel. The NC device 50 cuts the sheet metal W by moving the relative position of the machining head 35 by the moving mechanism while the laser beam is displaced forward in the cutting direction.

FIG. 9 shows a state in which the sheet metal W is cut in a defocused state in which the position of the beam waist is positioned below the surface of the sheet metal W. In FIG. 9, the beam waist (the focal point of the laser beam) is located at the center of the sheet metal W in the thickness direction or in the vicinity thereof. The NC device 50 has a converging lens so that the beam waist is positioned at or near the center in the plate thickness direction of the sheet metal W, or below the surface of the sheet metal W and above the center in the plate thickness direction. It is preferable to adjust the position of 34 in the optical axis direction. The position of the beam waist may be adjusted by a method other than the method of adjusting the position of the focusing lens 34 in the optical axis direction.

When processing the sheet metal W using oxygen as an assist gas, the position of the focusing lens 34 in the optical axis direction may be adjusted so that the beam waist is positioned above or above the surface of the sheet metal W.

Further, as shown in FIG. 9, the NC device 50 positions the machining head 35 so that the center 36 ctr of the opening 36 a is located below the center in the sheet thickness direction of the sheet metal W in the cutting front CF. Is good.

9 and 10, the assist gas AG supplied to the machining head 35 by the assist gas supply device 80 is sprayed onto the sheet metal W through the opening 36a. When the laser beam is displaced to the front side in the cutting progress direction, the amount of assist gas AG acting on the molten metal Wmelt generated on the rear side in the cutting progress direction can be increased.

The machining condition database 70 stores an offset distance for displacing the laser beam forward in the cutting progress direction as one of the machining conditions at the time of approach machining or cutting of the outer periphery of the product. The NC device 50 uses the galvano scanner unit 32 to displace the laser beam forward in the cutting progress direction by an offset distance.

The amount of assist gas ejected from the nozzle 36 per unit time is proportional to the area of the opening 36a. Therefore, in order to reduce the consumption amount of the assist gas, it is conceivable to reduce the diameter (nozzle diameter) of the opening 36a. However, if the nozzle diameter is reduced, the flow rate of the assist gas is reduced, so that the dischargeability of the molten metal Wmelt is deteriorated, resulting in processing defects.

According to the laser processing machine 100 and the laser processing method of one or more embodiments, the amount of assist gas that acts on the molten metal Wmelt can be increased, so that it acts on the molten metal Wmelt even if the nozzle diameter is reduced. The substantial assist gas flow rate is not so small. Therefore, according to the laser processing machine 100 and the laser processing method of one or more embodiments, since the discharge of the molten metal Wmelt is hardly deteriorated to cause a processing defect, a nozzle having a smaller nozzle diameter than the conventional one. 36 can be used.

As an example, if the consumption amount of the assist gas when the nozzle 36 having a nozzle diameter of 4 mm is used is 100%, the consumption amount of the assist gas when the nozzle 36 having a nozzle diameter of 3 mm is used is 75%. According to the laser processing machine 100 and the laser processing method of one or more embodiments, the consumption amount of the assist gas can be 56% using the nozzle 36 having a nozzle diameter of 3 mm.

According to the laser processing machine 100 and the laser processing method of one or more embodiments, the consumption amount of the assist gas can be reduced by 44% in the above example, so that the manufacturing cost of the product can be reduced. .

The NC device 50 may vibrate with a predetermined vibration pattern in a state where the laser beam is displaced forward in the cutting direction by the galvano scanner unit 32 at the time of approach processing or cutting of the outer periphery of the product.

11 and 12 show examples of vibration patterns for vibrating the laser beam. The cutting progress direction of the sheet metal W is the x direction, and the direction orthogonal to the x direction in the plane of the sheet metal W is the y direction. 11 and 12 show vibration patterns in a state where the machining head 35 is not moved in the x direction so that the vibration patterns can be easily understood.

As shown in FIG. 11, the galvano scanner unit 32, based on the control by the NC device 50, converts the beam spot Bs into the groove Wk formed by the progression of the beam spot Bs as the first example of the vibration pattern in the x direction. Vibrate. This vibration pattern is referred to as a parallel vibration pattern.

The groove Wk formed in the sheet metal W without vibrating the laser beam has a kerf width K1. When the laser beam is vibrated in a parallel vibration pattern, the beam spot Bs vibrates in the groove Wk, so that the kerf width K1 does not change.

As shown in FIG. 12, the galvano scanner unit 32 vibrates the beam spot Bs in the y direction as a second example of the vibration pattern based on the control by the NC device 50. This vibration pattern is referred to as an orthogonal vibration pattern. When the orthogonal vibration pattern is used, the groove Wk has a kerf width K2 wider than the kerf width K1.

11 and FIG. 12, in fact, the laser beam vibrates while the machining head 35 moves in the cutting progress direction. The vibration pattern is obtained by adding a displacement in the cutting progress direction (x direction) to the vibration pattern.

The present invention is not limited to the one or more embodiments described above, and various modifications can be made without departing from the scope of the present invention.

The disclosure of the present application is related to the subject matter described in Japanese Patent Application No. 2018-044098 filed on Mar. 12, 2018, the entire disclosure content of which is incorporated herein by reference.

Claims

A machining head having a nozzle attached to the tip for emitting a laser beam from the opening;
A moving mechanism for moving the processing head relative to the surface of the sheet metal;
A beam displacement mechanism for displacing the position of the laser beam emitted from the opening in the opening;
An assist gas supply device for supplying an assist gas for spraying the sheet metal from the opening to the processing head during the processing of the sheet metal;
When performing piercing processing for opening a piercing to the outside of a product cut from the sheet metal by a laser beam as the processing of the sheet metal, the position of the laser beam emitted from the opening is changed from the center of the opening to the product. When the outer shape of the product is cut by a laser beam as the metal plate is moved to a position in the direction of separation, the position in the opening of the laser beam emitted from the opening is cut from the center of the opening. A control device for controlling the beam displacement mechanism so as to be displaced to the front side of
A laser processing machine.
A focusing point adjusting mechanism for adjusting a focusing point of a laser beam irradiated on the sheet metal;
The control device, when cutting the outer shape of the product, the laser beam focusing point is positioned below the surface of the sheet metal and above the center or the center of the sheet thickness of the sheet metal, The laser beam machine according to claim 1, wherein the laser beam machine controls a focusing point adjusting mechanism.
The beam displacement mechanism also functions as a beam vibration mechanism for vibrating the laser beam,
The laser processing machine according to claim 1, wherein the control device controls the beam vibration mechanism so as to vibrate a laser beam with a predetermined vibration pattern when cutting an outer shape of the product.
When performing a piercing process to open a piercing outside the product in order to cut the product from the sheet metal by the laser beam, the position in the opening of the laser beam emitted from the nozzle opening attached to the tip of the processing head, Displace from the center of the opening to a position away from the product,
During the piercing process, an assist gas is blown to the sheet metal from the opening, and the molten metal of the sheet metal melted by the heat of the laser beam is blown away in a direction away from the product around the piercing.
When cutting the outer shape of the product with a laser beam, the position of the laser beam emitted from the opening is displaced from the center of the opening to the front side in the cutting progress direction,
At the time of cutting the outer shape of the product, an assist gas is blown to the sheet metal from the opening, and the molten metal of the sheet metal melted by the heat of the laser beam is discharged from a groove formed around the outer shape of the product. .
The laser processing according to claim 4, wherein when cutting the outer shape of the product, a laser beam focusing point is positioned below the surface of the sheet metal and above the center of the sheet thickness of the sheet metal or above the center. Method.
6. The laser processing method according to claim 4, wherein the laser beam is vibrated in a predetermined vibration pattern when cutting the outer shape of the product.