JP6538910B1 - Laser processing machine and laser processing method - Google Patents

Abstract

An object of the present invention is to reduce the amount of molten metal adhering to the product side around a piercing at the time of piercing processing, reduce the consumption of assist gas when manufacturing a product by cutting a sheet metal, and reduce the manufacturing cost of the product. To provide a laser processing machine capable of reducing the
A beam displacement mechanism displaces the position of a laser beam emitted from an opening a of a nozzle within the opening a. The assist gas supply device 80 supplies an assist gas to the processing head 35 when processing the sheet metal W. The control device (NC device 50) controls the beam displacement mechanism so as to displace the position within the opening 36a of the laser beam from the center of the opening 36a to a position away from the product when performing piercing processing outside the product. Do. The controller controls the beam displacement mechanism so as to displace the position in the opening 36a of the laser beam from the center of the opening 36a to the front side in the cutting advancing direction when cutting the outer shape of the product.
[Selected figure] Figure 1

Description

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

  2. Description of the Related Art A laser processing machine is widely used which cuts a sheet metal with a laser beam emitted from a laser oscillator to produce a product having a predetermined shape. The laser processing machine is configured to spray the assist gas onto the sheet metal from the nozzle and discharge the molten metal within the kerf width when the laser beam is emitted from the nozzle to cut the sheet metal (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 drills a hole called "piercing" by a laser beam at a position outside the product of the sheet metal. The laser beam machine cuts the sheet metal along the product outline, after performing an piercing process to pierce the sheet metal with a laser beam, followed by cutting to a predetermined position of the product outline.

  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 to the sheet metal. During approach processing or cutting along the product profile, the molten metal melted by the heat of the laser beam is blown away by the assist gas from the grooves already cut to the back side of the sheet metal. However, at the time of piercing, since the groove or the hole is not formed, the molten metal is blown off to the surface of the sheet metal by the assist gas and adheres to the periphery of the piercing.

  Molten metal splashed during piercing should not adhere to the product side around the piercing. When performing piercing processing which pierces the sheet metal while spraying the assist gas onto the sheet metal, it is desirable to reduce the amount of molten metal adhering to the product side around the piercing.

  The greater the consumption of assist gas, the higher the manufacturing cost of the product. Therefore, it is desirable to reduce the manufacturing cost of the product by reducing the consumption of assist gas when the laser processing machine cuts the sheet metal to manufacture the product.

  One or more embodiments can reduce the amount of molten metal adhering to the product side around the piercing during piercing, and reduce the consumption of assist gas when cutting a sheet metal to make a product It is an object of the present invention to provide a laser processing machine and a laser processing method that can reduce the manufacturing cost of a product.

According to a first aspect of one or more embodiments, relatively a processing head nozzles for emitting the opening of the laser beam is attached to the distal end, the machining head against the surface of the sheet metal mobile Moving mechanism, a beam displacement mechanism for displacing the position of the laser beam emitted from the opening in the opening, and an assist gas for blowing the opening to the sheet metal from the opening when the sheet metal is processed An assist gas supply device for supplying, and a piercing process for piercing the outside of a product to be cut from the sheet metal by the laser beam as processing for the sheet metal, the position within the opening of the laser beam emitted from the opening is The product is displaced from the center of the opening to a position away from the product, and the product is processed by a laser beam as processing of the sheet metal. A controller for controlling the beam displacement mechanism so as to displace the position within the opening of the laser beam emitted from the opening forward of the center of the opening when cutting the outer shape; There is provided a laser processing machine characterized by

  According to a second aspect of one or more embodiments, the nozzle attached to the tip of the processing head when piercing is performed to pierce the exterior of the product to cut the product from the sheet metal by the laser beam The position in the opening of the laser beam emitted from the opening is displaced from the center of the opening to a position away from the product, and an assist gas is sprayed from the opening to the sheet metal during the piercing process. When the molten metal of the sheet metal melted by heat by the laser beam is blown 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 Displacing the position in the opening to the front side in the cutting advancing direction than the center of the opening; At the time of outer shape cutting, an assist gas is blown from the opening to the sheet metal, and the molten metal of the sheet metal melted by heat from the laser beam is discharged from a groove formed around the outer shape of the product. A processing method is provided.

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

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

  One or more embodiments of a laser processing machine and a laser processing method will be described below with reference to the attached drawings. In FIG. 1, a laser processing machine 100 generates a laser beam and emits a laser oscillator 10, a laser processing unit 20, and a process fiber 12 for transmitting a laser beam emitted from the laser oscillator 10 to the laser processing unit 20. And

  The laser processing machine 100 further 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 of 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-state 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 an example, 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 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 in the X-axis direction on the processing table 21. 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 are moving mechanisms for moving the processing 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 processing head 35 along the surface of the sheet metal W, the position of the processing head 35 may be fixed, and the sheet metal W may be configured to move. Laser processing machine 100 need only comprise a moving mechanism for relatively moving the processing head 35 against the surface of the sheet metal W.

  The processing head 35 has a circular opening 36a at its tip, and a nozzle 36 for emitting a laser beam from the opening 36a is attached. The laser beam emitted from the opening 36 a of the nozzle 36 is irradiated to the sheet metal W. The assist gas supply device 80 supplies, as an assist gas, nitrogen to the processing head 35 if the sheet metal W is stainless steel and oxygen if the sheet metal W is soft steel. At the time of processing the sheet metal W, the assist gas is blown to the sheet metal W from the opening 36 a. In any of the steel types, a mixed gas containing nitrogen and oxygen as components can be used as the assist gas according to the processing intention.

  At the time of piercing processing, the assist gas blows away the molten metal in which the sheet metal W is melted, and at the time of approach processing or cutting of the product outer shape, the assist gas discharges the molten metal within the kerf width. Cutting the product profile includes cutting the outer periphery of the product and cutting the inner periphery of the product to form an opening in the interior of the product. Hereinafter, the case where the product outer shape is the product outer periphery is taken as an example.

  As shown in FIG. 2, the collimator unit 30 includes a collimation lens 31 that converts the divergent laser beam emitted from the process fiber 12 into parallel light (collimated light). The collimator unit 30 further 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 which focuses the laser beam reflected by the bend mirror 33 and irradiates the sheet metal W with the laser beam.

  The focusing lens 34 is adjustable in position in the optical axis direction. The focusing lens 34 functions as a focusing point adjustment mechanism for adjusting the focusing point of the laser beam irradiated to 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 located 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 which travels in 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 where the laser beam is irradiated to the sheet metal W to a position separated from the position directly below the center of the opening 36 a by a predetermined distance.

  The galvano scanner unit 32 has 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 so as to have a predetermined angle. The galvano scanner unit 32 also has 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 so as to have a predetermined angle.

  The drive units 322 and 324 can also oscillate the scan mirrors 321 and 323 in a predetermined angular range based on control by the NC device 50. The galvano scanner unit 32 can vibrate the laser beam irradiated to the sheet metal W by reciprocating vibration of either or both of the scan mirror 321 and the scan mirror 323. That is, the NC apparatus 50 can also function the galvano scanner unit 32 as a beam vibrating mechanism that causes the laser beam traveling through the processing head 35 and emitted from the opening 36a to vibrate in the opening 36a.

  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 are tilted, and the position of the laser beam irradiated 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.

  In detail, the operation of the galvano scanner unit 32 positioned in front of the bend mirror 33 changes the angle of the optical axis of the laser beam incident on the bend mirror 33, and the optical axis is from the center of the bend mirror 33. Get out. In FIG. 3, the incident position of the laser beam to the bend mirror 33 is the same position before and after the operation of the galvano scanner unit 32 for simplification.

  It is assumed that the optical axis of the laser beam is displaced from the position shown by a thin solid line to the position shown by a thick solid line by the action of the galvano scanner unit 32. Assuming that the laser beam reflected by the bend mirror 33 is inclined at an angle θ, the irradiation position of the laser beam to the sheet metal W is displaced by a distance Δs. Assuming that the focal length of the focusing lens 34 is EFL (Effective Focal Length), the distance Δs is calculated by EFL × sin θ.

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

  The NC device 50 can displace the position where the laser beam is irradiated to the sheet metal W by controlling the drive parts 322 and 324 of the galvano scanner unit 32. The NC device 50 can also vibrate the laser beam in a predetermined direction in the plane of the sheet metal W. By vibrating the laser beam, the beam spot formed on the surface of the sheet metal W can be vibrated.

  As shown in FIG. 4, it is assumed that a plurality of rectangular products 200 are cut in a sheet metal W and the laser processing machine 100 cuts each product 200. A piercing process is performed at the position shown in FIG. 4 to open the pierced hole 201, and then the approach 202 is cut, and the sheet metal W is cut along the outer periphery of the product 200 from the end of the approach 202 on the product 200 side. It is assumed that a program has been created. The machining program is stored in the machining program database 60.

  The NC apparatus 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 apparatus 50 controls the laser processing machine 100 to process the sheet metal W based on the read processing program and the selected processing conditions.

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

  If the thickness of the sheet metal W is large, the time until the piercing 201 is formed may be long, and a phenomenon may occur in which the melted portion immediately below the center of the opening 36a slightly moves 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 directly above the opening position of the pierced hole 201 and the assist gas is sprayed on the sheet metal W, more molten metal is scattered in the direction in which the amount of molten metal is biased. . Although both the spattered molten metal and the deposited metal mass attached to and solidified on the sheet metal W may be referred to as sputtering, 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 scatters 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. By adopting, the position in the opening 36a of the laser beam is displaced from the center of the opening 36a to a position in a direction away from the product 200.

  In the first displacement method, as shown in FIG. 5B, the NC device 50 is positioned directly above the position where the center of the opening 36a is displaced toward the product 200 on the approach 202 than the coordinates (X1, Y1). Thus, the processing head 35 is displaced to the product 200 side along the approach 202. In addition to this, the NC device 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 to the sheet metal W becomes coordinates (X1, Y1). As a result, the position where the laser beam is irradiated to the sheet metal W is displaced not to be directly under the center of the opening 36 a but to the side away from the product 200.

  In the second displacement method, as shown in FIG. 5C, the NC device 50 positions the processing head 35 such that the center of the opening 36a is located at the coordinates (X1, Y1). In addition to this, the NC apparatus 50 places the laser beam on the sheet metal W in a galvano scanner so that the position on the extension of the approach 202 is 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 where the laser beam is irradiated to the sheet metal W is displaced not to be directly under the center of the opening 36 a but to the side away from the product 200.

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

  6 conceptually shows an operation of piercing the sheet metal W with the laser beam displaced outward from the center 36 ctr of the opening 36 a when viewed from the side direction of the processing head 35, and FIG. 7 shows the upper side of the sheet metal W It has shown notionally the state which looked at sheet metal W from it. When piercing the sheet metal W, the NC device 50 raises the processing head 35 so as to separate the nozzle 36 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 and away from the sheet metal W.

  As shown in FIG. 6 and FIG. 7, although the assist gas AG is uniformly sprayed to 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 a displacement of the laser beam Splash in the direction you Even if the amount of molten metal Wmelt is biased toward the product 200 side, the distance Δs for displacing the laser beam on the sheet metal W is much larger than the distance over which the amount of molten metal Wmelt is biased. Scatter in the direction of displacement.

  If the position at which the laser beam is irradiated to the sheet metal W is displaced from immediately below the center 36ctr of the opening 36a 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 flies away from the product 200.

  Therefore, according to the laser beam machine 100 and the laser beam machine method executed by the laser beam machine 100 of one or more embodiments, as shown in FIG. Sputter Sp can be deposited on the opposite side, and control can be performed so that spatter Sp hardly adheres to the product 200 side. Therefore, since the piercing 201 can be opened near the product 200, the distance D between the adjacent products 200 shown in FIG. 4 can be narrowed. As a result, according to the laser processing machine 100 and the laser processing method of one or more embodiments, it is possible to improve the yield.

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

  In FIGS. 5B and 5C, the direction of displacing the position of the laser beam irradiated to the sheet metal W is a direction away from the product 200 along the approach 202, but is not limited to the direction along the approach 202. The direction away from the product 200 may not be the direction along the approach 202.

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

  As shown in FIG. 9 or FIG. 10, at the time of approach processing or cutting of the product outer periphery, the NC device 50 cuts the laser beam (beam spot Bs shown in FIG. 10) by the galvano scanner unit 32 than the center 36ctr of the opening 36a. It is displaced forward in the direction of travel. The NC device 50 cuts the sheet metal W by moving the relative position of the processing head 35 by the moving mechanism in a state where the laser beam is displaced forward in the cutting advancing 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 located below the surface of the sheet metal W. In FIG. 9, the beam waist (the focal point of the laser beam) is located at or near the center of the sheet metal W in the thickness direction. The NC apparatus 50 is a focusing lens so that the beam waist is located at or near the center in the thickness direction of the sheet W or below the surface of the sheet W and above the center in the thickness direction. It is preferable to adjust the position of the optical axis direction 34. 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 the sheet metal W is processed using oxygen as the 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 the surface or the surface of the sheet metal W.

  Furthermore, as shown in FIG. 9, the NC device 50 positions the processing head 35 so that the center 36 ctr of the opening 36 a is positioned lower than the center in the thickness direction of the sheet metal W in the cutting front CF. Is good.

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

  The processing condition database 70 stores, as one of processing conditions at the time of approach processing or cutting of the product outer periphery, an offset distance for displacing the laser beam to the front side in the cutting advancing direction. The NC device 50 causes the galvano scanner unit 32 to displace the laser beam to the front side in the cutting traveling direction by the offset distance.

  The amount of assist gas ejected from the nozzle 36 per hour is proportional to the area of the opening 36 a. Therefore, in order to reduce the amount of consumption 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 decreases, so the dischargeability of the molten metal Wmelt deteriorates and processing defects occur.

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

  As an example, assuming that the consumption of assist gas when using a nozzle 36 with a nozzle diameter of 4 mm is 100%, the consumption of assist gas when using a nozzle 36 with a nozzle diameter of 3 mm is 75%. According to the laser processing machine 100 and the laser processing method of one or more embodiments, the consumption amount of assist gas can be 56% using the nozzle 36 with 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 apparatus 50 may vibrate with a predetermined vibration pattern in a state where the laser beam is displaced to the front side in the cutting advancing direction by the galvano scanner unit 32 at the time of approach processing or cutting of the product outer periphery.

  11 and 12 show an example of a vibration pattern for vibrating a laser beam. The cutting advancing 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 a vibration pattern in a state in which the processing head 35 is not moved in the x direction so that the vibration pattern can be easily understood.

  As shown in FIG. 11, the galvano scanner unit 32 is based on the control by the NC device 50, and as a first example of the vibration pattern, the beam spot Bs in the groove Wk formed by the progress of the beam spot Bs 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 in a state in which the laser beam is not vibrated has a kerf width K1. When the laser beam is oscillated in a parallel oscillation pattern, the beam spot Bs oscillates in the groove Wk, so 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 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.

  In either of the parallel vibration pattern shown in FIG. 11 and the orthogonal vibration pattern shown in FIG. 12, since the laser beam vibrates while the processing head 35 moves in the cutting direction, in fact, it is shown in FIG. It becomes the vibration pattern which added the displacement of the cutting advancing 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.

DESCRIPTION OF SYMBOLS 10 laser oscillator 12 process fiber 20 laser processing unit 30 collimator unit 31 collimation lens 32 galvano scanner unit 33 bend mirror 34 focusing lens 35 processing head 36 nozzle 36a opening 40 operation part 50 NC apparatus (control device)
60 machining program database 70 machining condition database 80 assist gas supply apparatus 100 laser beam machine 321, 323 scan mirror 322, 324 drive unit W sheet metal

Claims (6)

A processing head having a nozzle attached at its tip for emitting a laser beam from the opening;
A moving mechanism for relatively moving the machining head against the surface of the sheet metal,
A beam displacement mechanism for displacing the position of the laser beam emitted from the aperture within the aperture;
An assist gas supply device for supplying an assist gas for blowing to the sheet metal from the opening to the processing head at the time of processing the sheet metal;
When a piercing process is performed to pierce the outside of a product to be cut from the sheet metal by a laser beam as processing of the sheet metal, the position within the opening of the laser beam emitted from the opening is from the product from the center of the opening When displacing the position of the away direction and cutting the outer shape of the product with a laser beam as processing of the sheet metal, the position in the opening of the laser beam emitted from the opening is cut from the center of the opening A controller for controlling the beam displacement mechanism to displace the beam forward of the
A laser processing machine comprising: A focusing point adjusting mechanism for adjusting a focusing point of a laser beam irradiated to the sheet metal;
The control device is configured to position the focal point of the laser beam below the surface of the sheet metal and above the center or the center of the thickness of the sheet metal when cutting the outer shape of the product. The laser beam machine according to claim 1, which controls a focusing point adjustment mechanism. The beam displacement mechanism also functions as a beam vibration mechanism for vibrating the laser beam,
The laser beam machine according to claim 1 or 2, wherein the control device controls the beam vibration mechanism to vibrate the laser beam in a predetermined vibration pattern when cutting the outer shape of the product. When a piercing process is performed to pierce the outside of the product in order to cut a product from a sheet metal by a laser beam, the position within the aperture of the laser beam emitted from the aperture of a nozzle attached to the tip of the processing head is Displacing from the center of the opening to a position away from the product,
At the time of the piercing process, an assist gas is sprayed from the opening to the sheet metal to blow away the molten metal of the sheet metal melted by heat by the laser beam in a direction away from the product around the piercing.
When the outline of the product is cut by a laser beam, the position within the opening of the laser beam emitted from the opening is displaced from the center of the opening to the front side in the cutting advancing direction;
At the time of cutting the outer shape of the product, an assist gas is blown from the opening to the sheet metal, and the molten metal of the sheet metal melted by heat by the laser beam is discharged from a groove formed around the outer shape of the product. Laser processing method.   When cutting the outline of the product, the focal point of the laser beam is located below the surface of the sheet metal and above the center or center of the thickness of the sheet metal. The laser processing method as described in.   The laser processing method according to claim 4 or 5, wherein when cutting the outer shape of the product, the laser beam is vibrated in a predetermined vibration pattern.

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