JPH0724578A - Method and device for plasma cutting - Google Patents

Abstract

PURPOSE:To finish both of the cut surface to one end to constitute a product by cutting both cut surface at right angles to the surface of material to be cut by cutting at a time by utilizing a cutting characteristic of the plasma gas turning flow where an inclined angle of the cut surface being right angle to the surface of the material to be cut is obtained. CONSTITUTION:The plasma cutting device is provided with a torch 1 which injects plasma gas 1a by turning clockwise for the thickness direction of the material W to be cut, a torch 2 which injects plasma gas 2a by turning anticlockwise for the thickness direction of the material W to be cut, a fitting member 3 which arranges the torch 1 and the torch 2 on the right side and the left side, respectively at a specified interval for the cutting direction and a moving means which moves the fitting member 3 in the specified direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma cutting method and a plasma cutting apparatus, and particularly to one end where both sides of a cutting groove constitute a product by cutting a material to be cut using a plurality of plasma torches in one cutting. The present invention relates to a plasma cutting method and a plasma cutting apparatus that can be finished as a sheet.

[0002]

2. Description of the Related Art It is well known that the angle of inclination of a cutting surface in plasma cutting is large, and it is not preferable when the cutting surface constitutes a part of a product. Therefore, in order to correct the inclination angle of the cutting surface, the cutting surface is finished after cutting, or the torch itself is cut with an appropriate inclination.

[0003]

However, when the torch itself is preliminarily provided with an inclination angle and the cutting surface is cut at a right angle to the surface of the material to be cut, the cutting surface depends on various conditions during cutting. There is a problem that the inclined angle of is not constant and a distorted cut surface is formed. Further, the inclination angle of one end of the cut surface can be controlled by using the technology for swirling the plasma gas developed by the present inventors (for example, the plasma gas swirling method and swirling device disclosed in Japanese Patent Application No. 5-59289). It has been found that it is possible to cut at right angles to the surface of the material to be cut, but even if this technology is used to cut the plasma gas by swirling with one torch, the surface of one cutting groove is Even if you can cut at a right angle to the surface of
The surface of the other cutting groove forms a larger inclination angle than that when the plasma gas is not swirled, and both surfaces of the cutting groove cannot be treated as products.

It is an object of the present invention to utilize the cutting characteristics of a plasma gas swirling flow, which can obtain a cutting surface whose inclination angle is perpendicular to the surface of a material to be cut, and makes use of the cutting characteristics of both cutting surfaces of a cutting groove in one cutting. By cutting at a right angle to the surface of the material to be cut, it is possible to finish both sides of the cutting groove as one end constituting the product.

[0005]

A plasma cutting method according to the present invention supplies a plasma gas around electrodes and
In a plasma cutting method in which a plasma arc is jetted from a nozzle to cut a material to be cut, a plasma torch configured to swirl the plasma gas to the right and a plasma torch configured to swirl to the left are configured Using the plasma torch, the traveling direction vector of the plasma torch and the tangential vector component of the swirling flow of the plasma gas cancel each other depending on the traveling direction of the plasma torch and the product arrangement in the material to be cut. It is a plasma cutting method characterized by cutting by combining plasma torches in parallel.

Further, the plasma cutting apparatus according to the present invention is a plasma cutting apparatus for cutting a material to be cut by using a plasma torch for supplying a plasma gas around the electrode and jetting a plasma arc from a nozzle. A first plasma torch which injects plasma gas by swirling the plasma gas to the right with respect to the thickness direction of the material to be cut, and a second plasma torch which swirls plasma gas to the left in the thickness direction of the material to be cut and injects A torch, a mounting member for mounting the first plasma torch and the second plasma torch in parallel, and a moving means for moving the mounting member in a predetermined direction. It is a plasma cutting device.

[0007]

The present inventors have the following view on the relationship between the swirling flow of the plasma gas and the inclination angle of the cut surface. Therefore, the explanation will be given with reference to FIGS. The plasma torch 1 in which the plasma gas is swirled right at a speed Vf with respect to the thickness direction of the material W to be cut is used as the material W to be cut.
When the scanning is performed in the direction of the vector Vt at a speed Vt at a right angle to the surface of the cut surface 3, the cut surface 3 is formed.

In FIG. 4, the flow velocity vector Vfr in the tangential direction of the swirling flow 1a at the point r of the swirling flow 1a of the plasma gas is formed in the direction opposite to the traveling direction Vt of the torch 1. Further, the flow velocity vector Vf in the tangential direction of the swirl flow 1a at the point b of the swirl flow 1a of the plasma gas.
The b is formed in a direction at the right angle to the traveling direction Vt of the torch 1. In addition, the flow velocity vector Vfl in the tangential direction of the swirl flow 1a at the point 1 of the swirl flow 1a of the plasma gas.
Are formed in the same direction as the traveling direction Vt of the torch 1. The tangential flow velocity vector Vff of the swirling flow 1a at the point f of the swirling flow 1a of the plasma gas is formed in the right-right direction with respect to the traveling direction Vt of the torch 1.

Therefore, the combined flow velocity vector of the velocity vector Vt of the plasma torch 1 and the flow velocity vector Vf of the swirling flow 1a is the advancing direction Vt of the torch 1 at the point r.
Is represented by a combined flow velocity vector having a scalar amount of | Vt | − | Vfr |. Further, the combined flow velocity vector at the point l is | Vt | with respect to the traveling direction Vt of the torch 1.
It is represented by the combined flow velocity vector with a scalar quantity of + | Vfl |.

Therefore, since the combined flow velocity vector Vcl for the cut surface 3l on the left side of the torch 1 traveling direction has a scalar quantity of | Vt | + | Vfl | at the point l, the traveling speed Vt of the torch 1 and the swirling flow are obtained. A scalar amount added with the flow velocity Vf of 1a is generated in the traveling direction of the torch 1. Further, the combined flow velocity vector Vcr for the cut surface 3r on the right side with respect to the traveling direction of the torch 1 is |
Since it has a scalar quantity of Vt |-| Vfl |, the traveling speed Vt of the torch 1 and the flow velocity Vf of the swirl flow 1a cancel each other out, so that a scalar amount is generated in the traveling direction. When the traveling speed Vt is exceeded, the scalar quantity is generated in the anti-traveling direction of the torch 1 as shown in FIG. Although not shown, when the flow velocity Vf of the swirling flow 1a is lower than the advancing velocity Vt of the torch 1, the scalar amount is generated in the advancing direction of the torch 1.

When the material W to be cut is cut at a right angle to the surface of the material W to be cut by the plasma torch 1 (not shown) using the swirling flow 1a described above, FIG. It is a cutting surface on the left side with respect to the traveling direction, and is formed with an inclination angle of θl from a surface perpendicular to the surface of the material W to be cut. 3r is a cutting surface on the right side with respect to the torch traveling direction, and is formed at a right angle to the surface of the material W to be cut. Alternatively, depending on the cutting conditions, it is formed with an inclination angle of θr from a plane perpendicular to the surface of the material W to be cut. At this time, there is a relation of θl> θr and θr is extremely small. Therefore, the left cutting surface 3l has a large inclination angle and is not preferable for one end constituting the product, but the right cutting surface 3r has an extremely small inclination angle and can cut the product W at substantially right angles to the surface thereof. It can be a preferable cut surface at one end of the structure.

From the principle for explaining the action of the swirling flow and the result of the inclination angle of the cut surface, when the plasma gas is swirled, the advancing direction of the torch and the swirling flow are relative to the advancing direction of the torch. The angle of inclination of the cut surface is large when the tangential component of the torch is equal, and the advancing direction of the torch and the tangential component of the swirl flow are opposite to the advancing direction of the torch. Can be concluded that the angle of inclination of the cut surface is extremely small.

Therefore, a technique to which the above principle is applied will be described with reference to FIGS. 2 and 3. A plasma torch 1 in which the plasma gas 1a is swirled to the right in the thickness direction of the material W to be cut.
Is arranged on the right side with respect to the cutting direction p, and the plasma torch 2 in which the plasma gas 2a is swirled counterclockwise with respect to the thickness direction of the material W to be cut is arranged on the left side with respect to the cutting direction p.

First, the torch 1 precedes to cut the material W to be cut to form the cut surface 3. Reference numeral 3r, which constitutes a part of the cutting surface 3, is a cutting surface on the right side with respect to the traveling direction p of the torch 1 and the torch 2, and the cutting surface is inclined as described above by appropriately setting the cutting conditions. The angle can be cut at a right angle to the surface of the material W to be cut. Further, 3l which constitutes a part of the cut surface 3 includes a torch 1 and a torch 2.
Is a cross section on the left side with respect to the traveling direction p of
The inclination angle of the cut surface is formed to be large.

Next, when the torch 2 cuts the material W to be cut after the torch 1, a cutting surface 4 is formed adjacent to the cutting surface 3. 4l which constitutes a part of the cut surface 4 is a left cut surface with respect to the traveling direction p of the torch 1 and the torch 2, and as described above, the inclination angle of the cut surface is relative to the surface of the material W to be cut. Can be cut at a right angle. In addition, a part of the cut surface 3 is formed to have a large inclination angle 3
1 is cut by the torch 2. Or torch 1
The cutting surface 3l is formed by arranging the cutting groove formed by the torch 2 and the cutting groove formed by the torch 2 with a predetermined gap.
Is formed in the scrap portion and cut off.

As described above, the right-side cutting surface 3r and the left-side cutting surface 4l with respect to the cutting direction p of the material W to be cut are cut at right angles to the surface of the material W to be cut, and thus both are cut. Can be finished as a cut surface forming a part of the product.

Therefore, in the plasma cutting method according to the present invention, as described above, the first torch for rotating and injecting the plasma gas rightward with respect to the thickness direction of the material to be cut is provided on the right side with respect to the cutting direction. The second torch, which disposes the plasma gas in the thickness direction of the material to be cut and swirls to the left in the thickness direction of the material to be cut, is arranged on the left side with respect to the cutting direction and combined in parallel, and simultaneously scans for cutting. By doing so, the torch on the right side with respect to the cutting direction cuts the right side cut surface at a right angle to the surface of the material to be cut, and at the same time, the torch on the left side with respect to the cutting direction cuts the left side cut surface with the cut surface. Since it cuts at a right angle to the surface of the material, both cutting surfaces can be cut at a right angle to the surface of the material to be cut at a time, and both cutting surfaces can be finished with the cutting surface that constitutes one end of the product. I can.

Further, the plasma cutting apparatus according to the present invention is
As described above, the mounting member for mounting the first torch and the second torch in parallel fixes the first torch and the second torch at predetermined positions, respectively, and the first torch. The second torch and the second torch can be mounted at positions where they do not interfere with each other, and can be configured with a desired cutting width.

Since the moving means for moving the mounting member in a predetermined direction is provided, the moving means moves the first torch and the second torch in desired directions and positions. In addition to the desired cut, both sides of the cut surface are cut at right angles to the surface of the material to be cut, so that both cut can be treated as a product.

[0020]

1 is a perspective view of a cutting apparatus according to the present invention, and FIG. 2 is a plasma gas swirl with respect to a material to be cut. FIG. 3 is an explanatory plan view showing the arrangement of the flow, and FIG. 3 is an explanatory sectional view showing the arrangement of the torch with respect to the material to be cut and the inclination angle of the cut surface.

In the figure, a plasma torch 1 is constructed so that a plasma gas 1a is swirled rightward around an electrode in the thickness direction of a material W to be cut and jetted and a plasma arc 1b is jetted. , A plasma torch 2 configured to inject a plasma gas 2a by rotating the plasma gas 2a to the left around the electrode in the thickness direction of the material to be cut W and a plasma arc 2b in parallel at predetermined positions. The mounting member 5 arranged and mounted on the carriage 6 is mounted on the traverse carriage 6 forming a part of the moving means A.

The mounting member 5 prevents the swirling flows of the plasma gas 1a and the plasma gas 2a from interfering with each other, and melts blown off by the torch 1 and the torch 2 during cutting are mutually separated. It is possible to hold the torch 1 and the torch 2 at a predetermined interval so as not to adversely affect the torch. still,
The method and apparatus for swirling the plasma gas can be easily realized by the configuration as shown in Japanese Patent Application No. 5-59289 as described in the above description of the problems, and therefore will not be described here.

The moving means A is mounted on a pair of rails 10 laid in parallel, and a traveling saddle 8a to which a traveling motor 9 for moving the rails 10 in a predetermined direction is attached; And a cross girder 8b provided in a direction orthogonal to the cross girder 8b and a cross girder 8b.
The traverse carriage 6 provided so as to be traversable along b
And a traverse motor 7 and the like attached to the traverse carriage 6 and driving the carriage 6.

Further, the moving means A is equipped with a numerical control device consisting of a control device 11 on the dolly 8.
The numerically controlled cutting device 11 controls the movement of the carriage 8, the traverse carriage 6, and the operations of the plasma torch 1 and the plasma torch 2.

The control device provides predetermined information for cutting the material W to be cut by using the plasma cutting device configured as described above.
When input to 11, the control device 11 operates the moving means A, the plasma torch 1 and the plasma torch 2. First, the torch 1 precedes and cuts the workpiece W to form the cut surface 3. A part 3r of the cut surface 3 is a right cut surface with respect to the traveling direction p of the torch 1 and the torch 2, and the inclination angle of the cut surface is cut at a right angle to the surface of the material W to be cut. it can. Further, 3l forming a part of the cut surface 3 is a cut surface on the left side with respect to the traveling direction p of the torch 1 and the torch 2, and the cut surface has a large inclination angle.

Next, when the torch 2 cuts the material W to be cut subsequent to the torch 1, a cut surface 4 is formed adjacent to the cut surface 3. 4l which constitutes a part of the cutting surface 4 is a cutting surface on the left side with respect to the traveling direction p of the torch 1 and the torch 2, and the inclination angle of the cutting surface is cut perpendicularly to the surface of the material W to be cut. it can. Further, 3 l, which constitutes a part of the cut surface 3 and has a large inclination angle, is a torch 2.
Is cut by. At this time, the torch 1 and the torch 2 are mounted with a sufficient space therebetween so that the torch 2 does not affect the cut surface 3r.

As described above, the right side cutting surface 3r and the left side cutting surface 4l with respect to the cutting direction p of the material W to be cut are cut at right angles to the surface of the material W to be cut, so that both of them are cut. Can be finished as a cut surface forming a part of the product.

In the present embodiment, the cutting groove formed by the torch 1 and the cutting groove formed by the torch 2 are overlapped with each other, but if necessary, separate cutting grooves may be formed for cutting. You can also Further, the plasma torch 1 in which the plasma gas 1a is swirled to the right with respect to the thickness direction of the material to be cut W is arranged on the right side with respect to the cutting direction p, and the material to be cut W
The plasma torch 2 in which the plasma gas 2a is swirled to the left with respect to the thickness direction of
Although the plasma torch 1 is preceded by the plasma torch 2, the plasma torch 2 is preceded by the plasma torch 2 under the above configuration.
May be followed. Alternatively, the plasma torch 1 and the plasma torch 2 may be arranged in parallel with each other while maintaining a predetermined interval at which they do not interfere with each other.

Further, in this embodiment, the plasma gas was swirled by the primary air stream, but when the plasma gas is composed of the primary air stream and the secondary air stream, it is possible to swirl one or both of them. Also in the case of the multiple air flow, it is possible to swirl any plasma gas.

[0030]

Since the plasma cutting method and the plasma cutting apparatus according to the present invention have the above-described structure and operation, both surfaces of the cutting groove obtained by cutting the material to be cut are used as one end of the product. It can be finished at right angles to the surface of the material to be cut. Therefore, the finishing work for correcting the inclined portion of the cut surface for finishing is not required.

Further, the cutting groove formed by the first plasma torch for rotating and jetting the plasma gas rightward in the thickness direction of the material to be cut, and the plasma gas in the thickness direction of the material to be cut. By cutting the cutting groove formed by the second plasma torch that is swirled leftward and jetted on top of each other, the scrap area at the time of cutting can be reduced, so that efficient cutting can be performed.

[Brief description of drawings]

FIG. 1 is a perspective view of a cutting device of the present invention.

FIG. 2 is an explanatory plan view showing an arrangement configuration of a plasma gas swirl flow with respect to a material to be cut.

FIG. 3 is a cross-sectional explanatory view showing a torch arrangement and a cut surface inclination angle with respect to a material to be cut.

FIG. 4 is a plan view for explaining the action of a plasma gas swirl flow on a cut surface.

FIG. 5 is a cross-sectional explanatory view of a cut surface for explaining the action of the plasma gas swirl flow on the cut surface.

[Explanation of symbols]

1, 2 ... Plasma torch 1a, 2a ...
Plasma gas 1b, 2b ... Plasma arc 3, 4 ... Cutting surface 5 ... Mounting member 6 ... Traverse carriage 7 ... Traverse motor 8 ... Cart 8a ... Travel saddle 8b ... Cross girder 9 ... Travel motor 10 ... Rail 11 ... Controller W ... Material to be cut A ... Moving means

Claims (2)

[Claims] 1. A plasma cutting method of supplying a plasma gas to the periphery of an electrode and jetting a plasma arc from a nozzle to cut a material to be cut, wherein the plasma gas is swirled rightward and jetted. The plasma torch and the plasma torch configured to inject the plasma gas by rotating the plasma to the left are used, and according to the traveling direction of the plasma torch and the product arrangement in the material to be cut, the traveling direction vector of the plasma torch and the plasma A plasma cutting method, comprising cutting the plasma torches in combination so that the tangential vector components of the swirling flow of gas cancel each other out. 2. A plasma cutting apparatus for cutting a material to be cut by using a plasma torch for supplying a plasma gas around an electrode and jetting a plasma arc from a nozzle, in a thickness direction of the material to be cut. Plasma torch for injecting the plasma gas by swirling the plasma gas to the right, a second plasma torch for injecting the plasma gas by swirling the plasma gas to the left in the thickness direction of the material to be cut, and the first plasma A plasma cutting apparatus, comprising: a mounting member for mounting the torch and the second plasma torch in parallel, and a moving means for moving the mounting member in a predetermined direction.