JP2004105972A - Laser cutting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser cutting system which can cut a desired heavy plate with a superior cutting result. <P>SOLUTION: The laser cutting system includes three laser oscillators 1 to 3 for a YAG laser beam, three optical fibers 6 to 8 to transmit each laser beam output from respective laser oscillators 1 to 3, a laser cutting machine 9 with a cutting head connected with each optical fiber 6 to 8 to cut a workpiece by irradiating the laser beam to the work transmitted through respective optical fibers 6 to 8, a control block diagram 11 to adjust the power of laser beam to be supplied to the laser cutting machine 9 by controlling the start and stop of respective laser oscillators 1 to 3. In the system, the numbers of laser oscillators to generate the necessary power is selected according to the thickness of the work. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser cutting processing system, and particularly to a case of cutting an extremely thick plate work (including a structure) by a laser cutting processing machine capable of remotely transmitting an output laser beam through an optical fiber, such as a YAG laser. It is useful.
[0002]
[Prior art]
Since the laser beam has very good directivity and large energy, it is widely used for processing such as cutting of a steel sheet as a high-energy laser beam focused on a small point. One type of such laser processing machine is a YAG laser oscillator which is a solid-state laser oscillator. This YAG laser oscillator uses a YAG (yttrium, aluminum, garnet) crystal doped with Nd as a laser single crystal. Laser light in the infrared region having a wavelength of 1.064 μm is converted into pulse laser light or continuous wave laser light. Output as. Since laser light from a YAG laser oscillator can be transmitted through an optical fiber, a welding apparatus or cutting apparatus using a YAG laser oscillator can route the laser light through an optical fiber, and the degree of freedom in selecting a work location. And, it has a feature that the degree of freedom of work mode is large.
[0003]
[Problems to be solved by the invention]
However, since the maximum value of the output of the YAG laser oscillator according to the prior art is relatively small, the thickness is limited when it is used for cutting a steel sheet.
[0004]
On the other hand, steel plates, which are workpieces that are to be cut with a laser cutting machine, have recently been in the trend of thickening. For example, considering the case where a laser cutting machine is applied to the dismantling of a nuclear reactor, a cutting ability of a thick plate of 80 mm to 100 mm is required.
[0005]
Incidentally, the following Patent Document 1 can be cited as a conventional technique for outputting various types of laser light from a single laser processing apparatus and obtaining appropriate laser light according to the processing. This is configured so that the output laser beams of a plurality of laser oscillators are combined and output by a light combining optical system formed by a reflecting mirror system and an optical fiber incident optical system. By performing oscillation / stop control, it is possible to obtain an optimum laser beam corresponding to the processing.
[0006]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-97939
An object of the present invention is to provide a laser cutting processing system capable of satisfactorily cutting a desired thick plate in view of the above-described prior art.
[0008]
[Means for Solving the Problems]
The configuration of the present invention that achieves the above object is characterized by the following points.
[0009]
1) In a laser cutting system that cuts a workpiece by transmitting laser light oscillated by a laser oscillator remotely using an optical fiber,
A plurality of laser oscillators such as a YAG laser oscillator capable of extracting output laser light with an optical fiber;
A plurality of optical fibers that transmit the output laser light of each laser oscillator;
A cutting head connected to each optical fiber and cutting the workpiece by irradiating the laser beam transmitted by each optical fiber toward the workpiece; and
And control means for adjusting the output of the laser beam supplied to the cutting head by controlling the oscillation and stopping of each laser oscillator.
[0010]
2) In a laser cutting system that cuts a workpiece by remotely transmitting laser light oscillated by a laser oscillator through an optical fiber,
A plurality of laser oscillators such as a YAG laser oscillator capable of extracting output laser light with an optical fiber;
A plurality of optical fibers that transmit the output laser light of each laser oscillator;
A cutting head connected to each optical fiber and cutting the workpiece by irradiating the laser beam transmitted by each optical fiber toward the workpiece; and
A plate thickness detection means for measuring the plate thickness of the workpiece;
Control means for controlling oscillation / stop of each laser oscillator so that an output laser beam set in advance according to the plate thickness detected by the plate thickness detecting unit is supplied to the cutting head.
[0011]
3) In the laser cutting system described in 1) or 2) above,
The control means controls so that the rise and fall timings of the output laser light of each laser oscillator are synchronized.
[0012]
4) In the laser cutting system described in 1) to 3) above,
The workpiece to be cut is a very thick plate or structure, and the cutting head is mounted on a head moving device built around the cutting object and can be cut.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0014]
FIG. 1 is a block diagram showing a laser processing system according to an embodiment of the present invention. As shown in the figure, this embodiment superimposes three laser oscillators 1, 2, 3 and the output laser beams of the laser oscillators 1 to 3, and an optical fiber 6 for transmitting the laser beams remotely, 7 and 8 and a processing stage 10 having a laser cutting machine (including a cutting head) 9 that performs cutting using laser light.
[0015]
Here, the optical fiber 6 transmits only the output laser light of the laser oscillator 1. The optical fiber 7 is a twin optical fiber and transmits the laser beams output from the laser oscillators 1 and 2 in a superimposed manner. Therefore, an output obtained by adding the outputs of the laser oscillators 1 and 2 can be obtained from the optical fiber 7. The optical fiber 8 is a triple optical fiber that transmits the output laser beams of the laser oscillators 1 to 3 in a superimposed manner. Therefore, an output obtained by adding the outputs of the laser oscillators 1 to 3 can be obtained from the optical fiber 8. Note that the combination of the optical fibers 6 to 8 need not be limited to that of this embodiment. They can be combined appropriately as required for the cutting process. Further, the cutting stage can be provided not only at one place but also at a plurality of places. Of course, it is possible to obtain different types of output laser beams at each cutting stage.
[0016]
The control unit 11 is formed by a programmable logic controller (PLC), controls the oscillation / stop of the laser oscillators 1 to 3 in accordance with a program incorporated in advance, and supplies an optical fiber to the laser cutting machine 9 Select one of 6 to 8 to control its output. That is, according to the thickness of the steel sheet to be cut by the processing stage 10, when only the output of one laser oscillator 1 is used, when the outputs of the two laser oscillators 1 and 2 are used in combination, The operation is performed in three modes in which the outputs of the laser oscillators 1 to 3 are used in a superimposed manner. This is realized by selecting the optical fibers 6 to 8 to be used together with selective oscillation / stop control of the laser oscillators 1 to 3.
[0017]
The cutting process may be programmed in advance, but may be sequentially determined by operating the processing machine side operation command panel 14. At this time, the operator selects one of the laser processing machines 1 to 3 and the optical fibers 6 to 8 to be used according to the thickness of the steel material to be cut.
[0018]
On the other hand, a plate thickness detection sensor 15 is provided in the vicinity of a steel plate that is a workpiece in the cutting process, and the laser processing machines 1 to 3 and the use are automatically made according to the plate thickness detected by the plate thickness detection sensor 15. It is also possible to automatically select one of the optical fibers 6 to 8 to be performed.
[0019]
Further, the control unit 11 in this embodiment controls so that the rising and falling timings of the output laser beams of the laser oscillators 1 to 3 are synchronized. This is realized by making the oscillation of the laser oscillators 1 to 3 and the oscillation stop command signal into analog electric signals. That is, the oscillation and oscillation stop command signals are supplied to the laser oscillators 1 to 3 via the electric wires 12a, 12b, 12c and the I / O port (not shown). The other laser oscillators 1 to 3 are controlled by using conventional BUS communication or the like via the communication line 13.
[0020]
Thus, the control unit 17 controls each laser oscillator 1 so that the energy of the laser beam supplied to the laser cutting machine 9 becomes appropriate according to the plate thickness of the steel sheet that is a workpiece to be cut by the laser cutting machine 9. To 3 and optical fibers 6 to 8 are selectively controlled.
[0021]
According to this embodiment, even a steel plate having a thickness that cannot be cut by the output laser light of one laser oscillator 1 to 3 can be cut well. In addition, as shown in FIG. 2, even when superposed laser beams from the laser oscillators 1 to 3 are obtained via optical fibers 7 and 8, for example, the rising and falling edges can be matched with high accuracy. In the case of cutting, it is not always necessary to match the rise and fall of the laser beam with high accuracy. However, if laser light with a predetermined output is obtained at the timing that matches with high accuracy, a single laser beam is used. Since a hole can be drilled in the steel material by irradiation, a good cutting process can be performed accordingly.
[0022]
Since the laser beam is supplied to the cutting head in the present invention via an optical fiber, the cutting head can be freely handled. Therefore, for example, as shown in FIG. 3, a workpiece to be cut is set as a nuclear reactor vessel 16, and the cutting head 17 moves the traveling rail 18 constructed around the nuclear reactor vessel 16 on the X axis (horizontal). It can also be mounted on a robot 19 that moves in the direction and the Y-axis (vertical) direction to perform cutting for dismantling the reactor vessel 16.
[0023]
Although the reactor vessel 16 is generally formed of a thick steel plate, according to the present invention, it is possible to obtain an output laser beam obtained by adding the outputs of a plurality of laser oscillators. It can be done well.
[0024]
【The invention's effect】
As specifically described with the above embodiments, the invention described in [Claim 1] is an output in a laser cutting processing system that cuts a workpiece by remotely transmitting a laser beam oscillated by a laser oscillator through an optical fiber. A plurality of laser oscillators, such as a YAG laser oscillator that can extract laser light with an optical fiber, a plurality of optical fibers that respectively transmit output laser light of each laser oscillator, and each optical fiber connected to each optical fiber, A cutting head that cuts the workpiece by irradiating the transmitted laser light toward the workpiece, and a control means that adjusts the output of the laser light supplied to the cutting head by controlling oscillation and stopping of each laser oscillator. Because we have
Laser light with an appropriate output according to the plate thickness can be obtained. As a result, even a thick steel plate that cannot be cut with a single laser oscillator can be cut well. At this time, since the laser light is supplied by an optical fiber, the degree of freedom in handling can be maintained as usual.
[0025]
The invention described in [Claim 2] is a YAG laser oscillator capable of taking out output laser light with an optical fiber in a laser cutting processing system for cutting a workpiece by remotely transmitting laser light oscillated with a laser oscillator through an optical fiber. A plurality of laser oscillators, a plurality of optical fibers that respectively transmit laser beams output from the laser oscillators, and a laser beam that is connected to each optical fiber and transmitted by each optical fiber toward the workpiece. The cutting head that cuts the workpiece by means of, the plate thickness detection means that measures the plate thickness of the workpiece, and the output laser beam that is preset according to the plate thickness detected by the plate thickness detection means is supplied to the cutting head Control means for controlling the oscillation and stop of each laser oscillator,
In addition to the operation and effect of the invention described in [Claim 1], there is an effect that a predetermined cutting can be performed by automatically irradiating laser light with an optimum output according to the thickness of the workpiece.
[0026]
In the invention described in [Claim 3], in the laser cutting processing system described in [Claim 1] or [Claim 2], the control means is configured to control the rising and falling timings of the output laser light of each laser oscillator. Because it controls to synchronize,
In addition to the operation and effect of the invention described in [Claim 1] or [Claim 2], the necessary laser output can be accurately supplied at a necessary time, and the cutting process can be performed well by that amount.
[0027]
[Claim 4] The invention described in [Claim 4] is the laser cutting system according to [Claim 1] to [Claim 3], wherein the workpiece to be cut is an extremely thick plate or a structure, and the cutting head Is configured to be mounted on a head moving device built around the object to be cut and cut.
Processing can be performed easily and quickly.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a laser cutting processing system according to an embodiment of the present invention.
2 is a waveform diagram showing a state in which output laser beams of the laser oscillators shown in FIG. 1 are superimposed. FIG.
FIG. 3 is an explanatory diagram conceptually showing a relationship between a reactor vessel to be cut and a laser cutting system according to the present invention.
[Explanation of symbols]
1, 2, 3 Laser oscillator 6, 7, 8 Optical fiber 9 Laser cutting machine 11 Controller 15 Plate thickness detection sensor 16 Reactor vessel 17 Cutting head 18 Traveling rail 19 Robot

Claims (4)

In a laser cutting processing system that cuts a workpiece by remotely transmitting laser light oscillated by a laser oscillator through an optical fiber,
A plurality of laser oscillators such as a YAG laser oscillator capable of extracting output laser light with an optical fiber;
A plurality of optical fibers that transmit the output laser light of each laser oscillator;
A cutting head that is connected to each optical fiber and cuts the workpiece by irradiating the laser beam transmitted by each optical fiber toward the workpiece;
And a control means for adjusting the output of the laser beam supplied to the cutting head by controlling the oscillation and stopping of each laser oscillator. In a laser cutting processing system that cuts a workpiece by remotely transmitting laser light oscillated by a laser oscillator through an optical fiber,
A plurality of laser oscillators such as a YAG laser oscillator capable of extracting output laser light with an optical fiber;
A plurality of optical fibers that transmit the output laser light of each laser oscillator;
A cutting head that is connected to each optical fiber and cuts the workpiece by irradiating the laser beam transmitted by each optical fiber toward the workpiece;
A plate thickness detecting means for measuring the plate thickness of the workpiece;
Control means for controlling oscillation and stop of each laser oscillator so that an output laser beam set in advance according to the plate thickness detected by the plate thickness detection unit is supplied to the cutting head Cutting processing system. In the laser cutting processing system according to [Claim 1] or [Claim 2],
The laser cutting processing system characterized in that the control means controls so that the rise and fall timings of the output laser light of each laser oscillator are synchronized. In the laser cutting processing system according to [Claim 1] to [Claim 3],
The workpiece to be cut is a very thick plate or a structure, and the cutting head is mounted on a head moving device constructed around the cutting object and can be cut. Laser cutting system.

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