JPH11786A - Underwater laser water jet composite cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable even a thick plate to be cut at high speed underwater by providing a water jet head underwater in the rearside in the cutting direction of a laser head, jetting high pressure water to the fusion part and removing it. SOLUTION: The laser head 2 is set vertically to an object 1 to be cut. A laser beam emitted through an optical fiber 10 by a laser generator 4 is converged with a lens on a cutting position to be fused. With the object 1 irradiated vertically by the laser beam, the fusion efficiency is maximized, increasing the cutting capacity. The water jet head 3 is disposed, in a position inclined backward against the object 1 in the cutting direction, in the rear side of that cutting/advancing direction of the laser head 2. As a result, the fusion zone can be efficiently blown off and cut. The high pressure water is supplied to the water jet head 3 through piping 11 by a high pressure water supply part 5. Further, in the case of a thick plate, abrasives are supplied through piping 12 by an abrasive feeding part 6 and mixed in the high pressure water while cutting is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underwater laser-waterjet combined cutting apparatus for melting an object to be cut in water with a laser and removing the melted portion with high-pressure water for cutting.

[0002]

2. Description of the Related Art Metal materials, ceramics such as stones, FRs
Laser cutting and water jet cutting are used for cutting a wide range of materials such as P (fiber reinforced plastic) materials. In the laser cutting, a laser beam is used to heat and melt an irradiated portion, and the melted portion is blown off with a gas jet (for example, oxygen, nitrogen, air, or the like) to perform separation cutting. Laser cutting is performed in a gas such as air, in a vacuum, and in water. Waterjet cutting, on the other hand,
It blows off and cuts off the part injected by the kinetic energy of the water ejected at high pressure.In some cases, only water is injected, and in other cases abrasives are mixed into water.
The polishing action is added to the kinetic energy to increase the cutting ability. Waterjet cutting has not conventionally been used for cutting in water.

[0003]

The cutting speed of laser cutting is high, but the maximum cutting thickness is limited by the laser output of the laser generator. In the case of water jet cutting using only water, the cut plate thickness is limited to a thin one. When an abrasive is mixed, it is possible to cut even a thick plate, but there is a case where the use is restricted because the abrasive is scattered and pollutes the environment. There is also a restriction on the cutting start position. For example, in the case of a flat plate, cutting can be performed from the periphery to the center side, but cutting cannot be started from a place without an end such as the center. in this case,
A hole or the like is opened in advance at the cutting start position, and cutting is started from here. Further, the price of a nozzle for jetting a water jet is extremely expensive (for example, several million yen), and when an abrasive is used, it may be extremely worn and may not be economically usable.

[0004] The present invention has been made in view of the above problems, and has as its object to provide a cutting apparatus capable of cutting a thick plate at high speed in water.

[0005]

To achieve the above object, according to the first aspect of the present invention, there is provided a laser head provided in water for irradiating an object to be cut in water with laser light and melting the object.
A water jet head which is provided in the water behind the laser head in the cutting direction and injects high-pressure water to the melting portion to remove the melting portion.

[0006] The cutting portion is irradiated with a laser beam to be melted, and the cut portion is cut by blowing off the melted portion with a water jet. As the laser light, a laser light that is not absorbed by water, for example, a YAG laser or the like is used. Further, since the high-pressure water is much higher than the water pressure at the cutting position, there is no problem in removing the molten portion.
Since the kinetic energy of the high-pressure water is higher and the high-pressure water itself has a cutting ability as compared with the conventional method of blowing off the molten portion with the gas, the cutting ability is increased, and a thicker plate can be cut. In addition, cutting can be performed at a high speed in the same manner as conventional laser cutting in air.

In the invention according to claim 2, the water jet head is arranged to be inclined rearward in the cutting direction.

[0008] By injecting high-pressure water obliquely from the rear in the cutting direction of the melted portion generated by the laser beam, the melted portion can be efficiently removed.

According to the third aspect of the present invention, the high-pressure water contains an abrasive for abrading an object to be cut.

[0010] The use of abrasives increases the cutting ability with high-pressure water, so that the ability to blow off the melted portion of laser light increases. As a result, the cutting ability of the cutting method using laser light and water jet increases. It is possible to cut even thick plates. If it is underwater, there is little scattering of abrasives,
It is easy to collect this.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
This will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the underwater laser / waterjet combined cutting device of the present embodiment. The processing device 8 is a device for setting the object 1 to be cut in water, and moving the laser head 2 and the water jet head 3 that are integrally connected to each other in water to cut into a desired shape. In FIG. 1, the processing device 8 is disposed in the air and remotely controls the laser head 2 and the water jet head 3. However, the processing device 8 may be a device that is submerged near the object 1 to be cut. The laser generator 4 is a device that generates a laser beam with an output corresponding to the thickness of the object 1 to be cut and sends it to the laser head 2. The high-pressure water supply unit 5 is a device that supplies high-pressure water to the water jet head 3. The abrasive supply unit 6 is an apparatus for supplying an abrasive, and the abrasive is mixed into high-pressure water by the water jet head 3. The seal gas supply unit 7 supplies a dry gas to the front part of the laser head 2 to dry the inside to suppress the generation of water droplets and prevent the laser light from being distorted. The operation panel 9 controls the laser generator 4, the high-pressure water supply unit 5, the abrasive supply unit 6, the seal gas supply unit 7, and the processing device 8 to cut the object 1 to be cut.

FIG. 2 is a diagram showing a laser head and a water jet head. The laser head 2 is set perpendicular to the cutting target 1. Optical fiber 1 from laser generator 4
The laser beam sent through the lens 0 is focused on the cutting position by a lens and melted. When the object to be cut 1 is vertically irradiated with laser light, the melting efficiency is maximized and the cutting ability is increased. The focusing area is, for example, about 1 mm in diameter. The laser light used has a property that is not absorbed by water, and for example, a YAG laser light is used. The cutting target 1 is a metal material, a ceramic material such as stone, an FRP material, or a composite thereof, for example, reinforced concrete.

The water jet head 3 is set at a position rearward of the laser head 2 in the cutting traveling direction and inclined rearward with respect to the cutting object 1 in the cutting traveling direction. Thereby, the molten portion can be efficiently blown off and cut. The high-pressure water is sprayed from the nozzle 3a at the tip, and the spray area is, for example, about 0.3 mm in diameter. High-pressure water is supplied to the waterhead 3 from a high-pressure water supply unit 5 through a pipe 11. Normally, cutting is performed using only high-pressure water. However, in the case of a thick plate, an abrasive is further supplied from the abrasive supply unit 6 via a pipe 12, mixed with high-pressure water, and cut. The abrasive is used when there is no problem even if the abrasive scatters at the cutting work place. In the case of underwater cutting, the abrasive material is less scattered and easy to collect, so that the usable environment is increased. Dry gas is supplied from the seal gas supply unit 7 to the front part of the laser head 2 via the pipe 13 to suppress the generation of water droplets inside and prevent laser light distortion.

FIG. 3 is a diagram showing an example of the configuration of the laser head. The laser head 2 includes a body 15, a front portion 16, and a rear portion 17, and the body 15 and the rear portion 17 have a watertight structure. The inside of the body 15 has a cylindrical shape and is provided with a condenser lens 19, and a partition plate 20 for transmitting laser light is provided on the front surface. The trunk portion 15 and the rear portion 17 are connected in a watertight manner. A fiber connector 18 is fitted to the rear end of the rear portion 17, and the fiber connector 18 is connected to the optical fiber 10 in a watertight manner.

The front portion 16 has a tip opening 21 at the tip,
A gas supply port 22 is provided on the rear end side, and the inside is cylindrical and narrowed at the front end. A dry gas (for example, air, nitrogen gas, or the like) is supplied from the gas supply port 22 and flows along the surface of the partition plate 20 to prevent moisture from adhering to the partition plate 20 and causing distortion of the laser beam. . This gas fills the inside of the front part 16 and flows out of the tip opening 21 to prevent water from entering the inside. Connector outlet 1
The laser light emitted from 8a becomes parallel light by the first lens 19, is condensed by the next lens 19, and is radiated to the cutting target 1 from the tip opening 21.

[0016]

As described above, according to the present invention, the following effects can be obtained by blowing off high-pressure water to cut off a melted portion melted by laser light in water. The cutting ability is increased as compared with a conventional apparatus that combines laser light and gas. The cutting speed is as high as the conventional laser cutting. By injecting high-pressure water while inclining the water jet head backward in the cutting direction, the molten portion can be efficiently removed. In water jet cutting, cutting only with high-pressure water can cut only a thin steel plate, but in the present invention, it can cut even a thick steel plate. In waterjet cutting, it is necessary to start cutting from a position where an end portion or a start hole is opened, but in the present invention, there is no such restriction and cutting can be started from anywhere. The cutting ability is further increased by mixing the abrasive with the high-pressure water. When an abrasive is not used, the tip nozzle of the water jet head can be used for a long time, and economical cutting can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of a laser head and a water jet head according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating an example of a configuration of a laser head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutting object 2 Laser head 3 Water jet head 3a Nozzle 4 Laser generator 5 High-pressure water supply part 6 Abrasive supply part 7 Seal gas supply part 8 Processing equipment 9 Operation panel 10 Optical fiber 11, 12, 13 Pipe 15 Body 16 Front 17 Rear 18 Fiber connector 18a Connector outlet 19 Lens 20 Partition plate 21 Tip opening 22 Gas supply port

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroto Yamaoka 1st Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Ishikawashima-Harima Heavy Industries, Ltd. 1 Haramachi Ishi Kawashima Harima Heavy Industries, Ltd.

Claims (3)

[Claims] 1. A laser head provided in water for irradiating a laser beam to an object to be cut in water and melting the same, and high-pressure water provided in the water behind the laser head in a cutting direction is injected to a melting portion to melt the same. An underwater laser-waterjet combined cutting device, comprising: a waterjet head for removing a part. 2. The underwater laser / water jet combined cutting apparatus according to claim 1, wherein the water jet head is arranged to be inclined backward in the cutting direction. 3. The high-pressure water contains an abrasive for abrading an object to be cut.
A combined underwater laser / water jet cutting apparatus as described in the above.