Method for laser processing

Patent metadata

Field	Value
Publication number	US-11052489-B2
Application number	US-201816651550-A
Country	US
Kind code	B2
Filing date	Oct 5, 2018
Priority date	Oct 6, 2017
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

In a laser processing method, laser lights of fiber lasers or direct diode lasers is irradiated onto an iron-based plate material from a nozzle, a nozzle with a nozzle opening whose opening diameter is preliminarily set according to a thickness of the plate material is selected from plural nozzles whose nozzle openings have different opening diameters from each other, and the plate material is cut while irradiating the laser lights onto the plate material and injecting assist gas from the nozzle opening toward the plate material.

First claim

The invention claimed is:

1. A laser processing method comprising:
irradiating an iron-based plate material with laser lights of fiber lasers or direct diode lasers from one of a plurality of nozzles whose nozzle openings have different opening diameters from each other;
selecting one of the plurality of nozzles to be used for irradiating the iron-based plate material with the laser lights that has a nozzle opening with an opening diameter preliminarily set according to a thickness of the plate material; and
cutting the iron-based plate material by injecting assist gas with a gas pressure of 0.4 to 1.0 MPa from the nozzle opening of the selected nozzle while irradiating the iron-based plate material with the laser lights, wherein
a nozzle selection table is made preliminarily and specifies opening diameters of the plurality of nozzles that produce good cutting of iron-based plate materials of different thicknesses with the gas pressure of 0.4 to 1.0 MPa with respect to each output power of the laser lights,
the nozzle selection table specifies more than one of the plurality of nozzles of different opening diameters produce good cutting of the iron-based plate material of a same thickness with the gas pressure of 0.4 to 1.0 MPa, the more than one of the plurality of nozzles are denoted as plural nozzles that produce good cutting of the iron-based plate material of the same thickness with the gas pressure of 0.4 to 1.0 MPa,
the selected one of the plurality of nozzles is selected from the plural nozzles,
the plural nozzles of different opening diameters each cut the iron-based plate material of the same thickness at a cutting speed with the gas pressure of 0.4 to 1.0 MPa, and one of the plural nozzles of different opening diameters achieves a maximum cutting speed for cutting the iron-based plate material of the same thickness with the gas pressure of 0.4 to 1.0 MPa compared to the cutting speed of the other plural nozzles for cutting the iron-based plate material of the same thickness with the gas pressure of 0.4 to 1.0 MPa, and
the selecting operation selects the one of the plural nozzles that achieves the maximum cutting speed for cutting the iron-based plate material of the same thickness with the gas pressure of 0.4 to 1.0 MPa according to the nozzle selection table that specifies the plural nozzles of different opening diameters that produce good cutting of the iron-based plate material of the same thickness with the gas pressure of 0.4 to 1.0 MPa.

2. The laser processing method according to claim 1 , wherein,
the iron-based plate material includes a first iron-based plate material and a second iron-based plate material,
the cutting includes a first cutting for cutting the first iron-based plate material and a second cutting for cutting the second iron-based plate material,
the second cutting for cutting the second iron-based plate material is to be done after the first cutting for cutting the first iron-based plate material and a first thickness of the first iron-based plate material is different from a second thickness of the second iron-based plate material, and
the second cutting is done by changing at least one of the opening diameter of the nozzle used in the first cutting and an output power of the laser lights based on comparison of the second thickness with the first thickness.

3. The laser processing method according to claim 1 , wherein,
the iron-based plate material includes a first iron-based plate material and a second iron-based plate material,
the cutting includes a first cutting for cutting the first iron-based plate material and a second cutting for cutting the second iron-based plate material,
the second cutting for cutting the second iron-based plate material is to be done after the first cutting for cutting the first iron-based plate material and a first thickness of the first iron-based plate material is equal to a second thickness of the second iron-based plate material, and
the second cutting is done by making one of the opening diameter of the nozzle and an output power of the laser lights used in the first cutting larger in the second cutting and making the other of opening diameter of the nozzle and the output power of the laser lights used in the first cutting smaller in the second cutting.

4. The laser processing method according to claim 1 , wherein
one of the plurality of nozzles is a double nozzle having an outer nozzle and an inner nozzle, and
the nozzle opening of the one of the plurality of nozzles being a double nozzle is an opening of the outer nozzle and an opening of the inner nozzle and is positioned on a deep-set side from the opening of the outer nozzle along an axial line of the nozzle.

5. The laser processing method according to claim 1 , wherein the iron-based plate material is made of stainless steel, and the assist gas is injected with a gas pressure of 0.4 to 0.8 MPa.

6. The laser processing method according to claim 1 , wherein the maximum thickness of the iron-based plate material subjectable to good cutting depends on the opening diameter of the one of the plurality of nozzles.

7. The laser processing method according to claim 1 ,
wherein a cutting tolerant thickness saturates when the nozzle opening diameter is 10 mm or larger so nozzles having an opening diameter greater than 10 mm produce good cutting only of iron-based plate materials whose thickness is no larger than the thickness of iron-based plate materials on which good cutting is achieved by a nozzle having an opening diameter of 10 mm, and
wherein the nozzle selection table identifies nozzles having an opening diameter greater than 10 mm as producing good cutting only of iron-based plate materials whose thickness is no larger than the thickness of iron-based plate materials on which good cutting is achieved by a nozzle having an opening diameter of 10 mm.

8. The laser processing method according to claim 1 , wherein the nozzle selection table specifies each of the plurality of nozzles with different opening diameters ranging from 2 mm to 12 mm as producing good cutting of the iron-based plate material for the iron-based plate material having a thickness of 10 mm, thereby rendering each of the plurality of nozzles as selectable for the iron-based plate material having a thickness of 10 mm.

9. The laser processing method according to claim 1 , wherein the nozzle selection table specifies two of the plurality of nozzles having different opening diameters ranging from 7 mm to 12 mm as producing good cutting of the iron-based plate material for the iron-based plate material having a thickness of 20 mm, thereby rendering the two of the plurality of nozzles as selectable for the iron-based plate material having a thickness of 20 mm.

Assignees

• Amada Holdings Co Ltd

Inventors

• Mizoguchi Yuya
• Ishiguro Hiroaki
• Ito Ryohei
• Kobayashi Ryo
• Masuda Kenji

Classifications

• B23K26/1482

  Detachable nozzles, e.g. exchangeable or provided with breakaway lines · CPC title

• B23K26/1462

  Nozzles; Features related to nozzles · CPC title

• B23K26/38 Primary

  by boring or cutting · CPC title

• B23K26/142

  for the removal of by-products · CPC title

• B23K26/40 Primary

  taking account of the properties of the material involved · CPC title