JPH04279284A - Plasma jet torch and plasma jet rocking method - Google Patents

Abstract

PURPOSE:To make the swing angle of plasma arc current large, to make the electric coil small, to make the power consumption little and to make the swing caused on the motion of plasma arc current little. CONSTITUTION:While closing the plasma stream path advancing from the plasma nozzle 6n to the plasma ejecting opening 11n by interposing the insulating tubular body 13 between the inner nozzle member 6 and the outer electrode member 11n, the electric coil 10a-10d are set at the outer side of the insulating body 13. The magnetic flux which crosses the insulating tubular body 13 is generated. Feasibly, two paires of electric polarities are opposed to the insulating tubular body 13 and charged to the four pieces of the electric coil with the sine wave AC by slipping the phase of every 90 degree, the plasma arc current is made to the circle motion with the same velocity.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma jet torch for injecting high-temperature gas turned into plasma by electric arc discharge, and a method for swinging the torch.

0002

2. Description of the Related Art Torches of this type are used for high-temperature treatment or processing of objects, for example for heating and melting metals.

For example, Japanese Unexamined Patent Publication No. 54-24249 discloses a defect removal method in which defects on the surface of a cast metal material or a rolled metal material are removed by melting the surface of the metal material with a transition type plasma jet torch. A method is presented. In order to remove a wide range of defects, an electromagnetic core is placed between the plasma jet torch and the metal material, and this is orthogonal to the arc, or plasma arc current, that transfers from the torch to the metal material. exerts a magnetic field that deflects the plasma arc current. By alternately reversing the current direction of the electromagnet, the plasma arc current moves back and forth and scans the surface of the metal material. This allows defects to be removed over a wide area. JP-A-54-24249 also discloses a mode in which an electric coil is inserted between a transfer type plasma arc current and a metal material, thereby causing the plasma arc current to reciprocate.

By the way, the non-transfer type plasma arc is
Although high-temperature extreme heating was a feature, surface treatment of steel plates on the micron order requires a uniform and wide-ranging heat source. However, until now there has been no plasma jet oscillation device for non-transfer type plasma jet torches.

[0005]

[Problems to be Solved by the Invention] A magnetic flux generator was attached to the outside of the tip of a non-transfer type plasma jet torch, and an alternating magnetic flux was applied to the ionized high-temperature plasma jet frame to cause it to oscillate, but there was a problem. It could not be put into practical use. In other words, since magnetic flux is applied to the flow of charges in the ionized plasma jet flame, the efficiency is very low compared to applying magnetic flux directly to the arc current, and a high-output magnetic flux generator is required. becomes. The plasma flame emitted onto the torch axis has strong directivity (inertial force), and requires a high-output magnetic flux generator to swing it. The magnetic flux generator is
Since it is located further forward of the tip of the chi, it is in a high temperature atmosphere, which poses a problem of heat resistance.

[0006] The present invention aims to improve this type of conventional problem.

[0007]

[Means for solving the problem] According to the first invention of the present application,
A non-transfer type plasma jet torch has an electrode (1) and a plasma nozzle (6n) located opposite the tip of the electrode (1).
) having an inner nozzle member (6), a gas flow path for supplying gas to the space between the inner nozzle member (6) and the electrode (1), and a plasma emitting device at a position facing the plasma nozzle (6n). Outer electrode member (11) having an opening (11n)
In a plasma jet torch having a plasma jet torch, a heat insulator is inserted between the inner nozzle member (6) and the outer electrode member (11) and surrounds the plasma flow path that advances from the plasma nozzle (6n) to the plasma exit opening (11n). It is characterized by comprising a cylinder (13); and an electric coil (10) for generating a magnetic flux across the insulating cylinder (13).

The non-transfer type plasma jet oscillation method according to the second invention of the present application includes an electrode (1) and an inner nozzle member (6n) having a plasma nozzle (6n) at a position opposite to the tip of the electrode (1). 6), a gas flow path for supplying gas to the space between the inner nozzle member (6) and the electrode, an outer electrode member (11) having a plasma exit opening (11n) at a position facing the plasma nozzle, and an inner nozzle. Member (6) and outer electrode member (1
A heat insulating cylinder (13) is inserted between the heat insulating cylinder (13) and surrounds the plasma flow path that advances from the plasma nozzle (6n) to the plasma exit opening (11n), and the tip surface faces the outer surface of the heat insulating cylinder (13). A magnetic core (9) having two or more pairs of pole tips (9a, 9b, 9c, 9d) facing each other with a heat insulating cylinder (13) in between, and wound around the magnetic core (9). and a plurality of electric coils (10a, 10b, 10c, 10d) for generating magnetic flux across the heat insulating cylinder (13) between the opposing magnetic pole tips (9a, 9b), (9c, 9d). The electric coil (10
a, 10b, 10c, 10d), each with a magnetic pole tip (
It is characterized by applying a sinusoidal alternating voltage that generates a rotating magnetic field to the space surrounded by the tips of the magnets 9a, 9b, 9c, and 9d).

Note that symbols in parentheses indicate corresponding elements in the embodiments shown in the drawings and described later.

0010

[Operation] In the non-transfer type plasma jet torch of the first invention, the electric coils (10a, 10b, 10c, 10
d) from the electrode (1) to the inner nozzle (6n) to the outer nozzle (8n)
n) Generates a magnetic flux that crosses the plasma arc current flowing between the heat insulating cylinder (13) and the outer electrode (11n).

When an alternating magnetic flux is caused to flow through the arc current, a force acts perpendicularly to the flow of the magnetic flux according to Fleming's left-hand rule, and the plasma arc current can be bent. Furthermore, when the direction of the magnetic flux flow is reversed, the acting force changes in the opposite direction.

Electric coils (10a, 10b, 10c, 1
If alternating current is used for 0d), the arc can be oscillated at a frequency corresponding to the alternating current period.

The plasma arc current is a heat source that heats the heated gas and turns it into a plasma jet flame.
At the same time, the fluctuation of the current causes fluctuation of the plasma jet flame.

[0014] Also, the position where the magnetic flux is applied is the arc in the torch.
Since the arc current is applied to the constricted portion, a magnetic field sufficient for deflection can effectively act on the plasma arc current with relatively small pole tips (9a, 9b). Therefore, the electric coils (10a, 10b, 10c, 10d) can obtain a relatively large deflection angle with a relatively small size.

Since the plasma arc current is deflected by the action of a magnetic field at the source and directed toward the material to be heat treated, such as a metal material, the amount of deflection of the plasma arc current at the surface of the metal material is large. In this way, a relatively large amount of deflection can be obtained with a relatively small electric coil, and only a small amount of electric power is required to apply the deflection magnetic field.

Furthermore, plasma arc current and electric coil (
10a, 10b, 10c, 10d) is provided with a heat insulating cylinder
13), and along with the fact that there is almost no fluctuation in the plasma arc current at the base, the electric coils (10a, 1
0b, 10c, 10d) will not be hit by the plasma flame, and the electric coil will not be burned out by the plasma flame. Since the heat insulating cylinder (13) is also located at the source of the plasma arc current, it does not come into contact with the plasma arc current even if it has a relatively small diameter.

[0017] In the plasma jet torch swinging method of the second invention, the effects of the above-mentioned first invention are similarly brought about, and the magnetic pole tips (9a, 9b, 9c, 9d
) are 2 or more pairs and electric coils (10a, 10b, 10c
, 10d) and a plurality of electric coils (10d).
a, 10b, 10c, 10d) is applied with a sinusoidal alternating voltage that generates a rotating magnetic field in the space surrounded by the tips of the magnetic pole tips (9a, 9b, 9c, 9d), so that the plasma arc current performs a circular motion along the circumference centered on the straight line connecting the tip of the electrode (1) and the center of the plasma nozzle (6n) (the central axis of the electrode 1), and the plasma arc current ) draw a cone between the metal materials. Since the alternating current applied to the electric coils (10a, 10b, 10c, 10d) is a sine wave, the circular motion is substantially uniform circular motion, so the plasma arc current moves very smoothly and has a good shape. is stable, and there is virtually no frame fluctuation due to deflection movement.

Other objects and features of each invention of the present application will become clear from the following description of embodiments with reference to the drawings.

[0019]

[First Embodiment] FIG. 1 shows a longitudinal section of an embodiment of the first invention of the present application, and FIG. 2 shows the bottom surface of the plasma jet torch shown in FIG. Note that FIG. 1 is a sectional view taken along the line II in FIG. 2. An electrode stand 4 is attached to the upper end of the torch main body 5, and an electrode cap 3 is coupled to this electrode stand 4. The electrode cap 3 tightens the chuck 2 through which the electrode 1 has passed, thereby positioning the electrode 1 at the central axis position of the cylindrical base 5.

An inner nozzle member 6 is attached to the lower end of the base 5, and a centering stone 7 is inserted between the inner nozzle member 6 and the electrode 1.
However, the electrode 1 is positioned at the lower end of the main body 5 so that the center axis of the electrode 1 is aligned with the center axis of the inner nozzle member 6. An inner nozzle (plasma nozzle) 6n is opened at the center of the lower bottom of the inner nozzle member 6. Electrode gas is supplied to the space between the electrode 1 and the inner nozzle member 6.

An outer nozzle member 8 is attached to the lower end of the main body 5, and an outer nozzle member 8 having a slightly larger diameter than the inner nozzle 6n is aligned with the center axis of the electrode 1 and the center axis of the inner nozzle 6n. Nozzle 8n is opened. A ring-shaped insulating collar 14 with a gas port opened in the radial direction is inserted between the outer surface of the lower bottom of the inner nozzle member 6 and the upper surface of the outer nozzle 8. Heated gas is supplied to the space between the inner nozzle member 6 and the outer nozzle member 8. Torch cooling water is supplied to the outer nozzle member 8, and this cooling water exits the outer nozzle member 8, passes through the channel of the trunk 5, enters the channel of the inner nozzle member 6, and exits the inner nozzle member 6. Further, it passes through the trunk 5 and is discharged to the outside of the torch.

The upper end of a ring-shaped heat insulating collar 13 is fixed to the outer surface of the lower bottom of the outer nozzle member 8.
An outer electrode 11 is fixed to the lower end of. In addition, outer electrode 1
1 is also fixed to the outer nozzle member 8 via an insulating material (not shown). The central axis of the circular space of the heat insulating collar 13 is aligned with the central axis of the outer nozzle 8n. The outer electrode nozzle 11n of the outer electrode 11 has a flattened conical shape that connects a circular opening continuous with the heat insulating collar 13 and an oval opening shown in FIG. That is, the shape of the outer electrode nozzle 11 is set so that the plasma arc current does not substantially directly hit the outer electrode 11 even when the plasma arc current is deflected in the left-right direction. Outer electrode cooling water is supplied to the water channel inside the outer electrode nozzle 11, and this cooling water is discharged to the outside of the outer electrode nozzle 11 through a recovery pipe (not shown).

A roughly C-shaped magnetic core 9 made of a laminate of silicon steel plates is disposed on the outer side of the heat insulating collar 13, and a pair of opposing magnetic pole tips 9a, 9b
sandwich the heat insulating collar 13. That is, the magnetic pole tip 9a
, 9b, there is a heat insulating collar 13 between the opposing end faces of the members. An electric coil 10 is wound around the magnetic core 9 . Note that the magnetic core 9 is fixed to the outer nozzle member 8 and the outer electrode 11 via an insulating material (not shown).

Electrode 1 (negative electrode) and inner nozzle member 6 (positive electrode)
An arc voltage is applied between the electrodes 1 and the inner nozzle 6n to generate an arc, and then a positive electrode voltage is applied to the outer nozzle member 8 to generate an arc between the electrode 1 and the inner nozzle 6n. By transferring the arc between electrode 1/outer nozzle 8n between electrode 1/outer nozzle 8n, and then applying a positive electrode voltage to outer electrode 11 to transfer the arc between electrode 1/outer nozzle 8n to between electrode 1/outer electrode nozzle 11n. , a plasma arc current is ejected from the outer electrode nozzle 11n. This plasma arc current flows through the electrode 1 and inner nozzle 6.
It is ejected along the extension line of the central axes of the outer nozzle 8n, the heat insulating collar 13, and the outer electrode nozzle 11n.

When the electric coil 10 is energized in the positive direction,
A magnetic flux flows between the magnetic pole tips 9a and 9b as shown by the dashed line in Figure 2, and the direction in which the plasma arc current flows (perpendicular to the plane of the paper in Figure 2) and the line connecting the magnetic pole tips 9a and 9b (vertical direction in Figure 2) and perpendicular direction (horizontal direction in Figure 2:
For example, the plasma arc current is deflected to the left (Fleming's left-hand rule: FIG. 3). Along with this, the plasma jet frame is also deflected in the same way. electric coil 1
When current is applied in the opposite direction to 0, the plasma arc current flows perpendicularly to the direction in which it flows (perpendicular to the plane of the paper in Figure 2) and to the line connecting the pole tips 9a and 9b (vertical in Figure 2). The plasma arc current is deflected in the direction (rightward in FIG. 2) (Fleming's left-hand rule). Along with this, the plasma jet frame is also deflected in the same way.

FIG. 3 shows how the plasma arc current is deflected when the electric coil 10 is energized. The deflection angle θ of the plasma arc current is determined by the arc current value of the plasma arc current and the magnetic field strength between the magnetic pole tips 9a and 9b, and the magnetic field strength is determined by the current value flowing through the electric coil 10. .

FIG. 4 shows the relationship between the magnetic flux density at the axial center position of the electrode 1 between the magnetic pole tips 9a and 9b and the deflection angle of the plasma arc current (arc deflection angle). As the magnetic flux density increases from about 40 Gauss to about 120 Gauss, the arc deflection angle increases substantially linearly. This large deflection at a relatively low magnetic flux density is due to the plasma arc.
In the case of arc current, the arc current value is high (e.g. 150A)
It is from.

The current value flowing through the electric coil 10 and the magnetic pole tip 9
FIG. 6 shows the relationship between the density of the magnetic flux generated between a and 9b. As shown in FIG. 5, the data in FIG.
The data A in FIG.
indicates the magnetic flux density at the end face position A of the magnetic pole tip 9b, and the data
Data B indicates the magnetic flux density at an intermediate point B on the central axis connecting the magnetic pole tips 9a and 9b, and data C indicates the magnetic flux density at a position 5 mm away from the central axis.

From the data shown in FIG. 4 and the data A shown in FIG. It can be seen that a magnetic flux density of about Gauss is required (FIG. 4), and in order to obtain this magnetic flux density, it is sufficient to flow a current of about 0.6 A through the electric coil 10. This current value is quite small compared to the obtained arc deflection angle.

In the embodiment shown in FIG.
Since there is one pair, the plasma arc current causes reciprocating motion in only one axis direction. As shown in FIG. 7A, by alternately energizing the electric coil 10 in the forward and reverse directions, the plasma arc current alternately moves to the left (FIG. 3) and to the right, from +θ° to -θ. It reciprocates within a range of °. Figure 7
As shown in (A), by repeating energization in the positive direction, energization pause, and reverse energization in this order in a pulsed manner, the plasma arc current changes from the +θ° deflection position, the center position, and the −θ° deflection position. It takes three positions and stops moving at these positions for a certain period of time, but the speed at which it moves between these positions is extremely fast. In other words, the movement of the plasma arc current becomes an inhomogeneous motion, which causes fluctuations in the plasma arc current due to back-and-forth aliasing, and the plasma arc current on the metal surface.
Uniform scanning of current (uniform heating scanning) cannot be obtained. Therefore,
When uniformly scanning a certain range of a continuous surface of the same metal material, as shown in FIG. 7(B), the electric coil 10 is
Apply a sinusoidal AC voltage. As a result, the plasma arc current becomes substantially uniform in motion between the turning points (+θ° deflection position, -θ° deflection position), which reduces fluctuations in the plasma arc current and makes it easier to scan the surface of the metal material. It becomes uniform.

In any case, as shown in FIG. 3, since a deflecting magnetic field is applied to the plasma arc current at the base of the outer nozzle 8n, the relatively low intensity of this deflecting magnetic field causes plasma arc current to flow. - The frame part near the tip of the arc current moves significantly to the left and right, resulting in a large amount of deflection. In other words, a relatively large amount of deflection can be obtained with a relatively small magnetic core 9 and electric coil 10. Since the current value passed through the electric coil 10 may be relatively low, power consumption is low. Insulation color 1
3 is located at the base, the plasma arc current will not directly hit it even if its diameter is relatively small, and the heat insulating collar 13 will prevent the plasma arc current from reaching the pole tips 9a, 9.
Blocks contact with b and high heat. In other words, insulation collar 13
However, the magnetic pole tips 9a and 9b can be arranged compactly.

[0032]

[Second Embodiment] FIG. 8 shows the bottom of another embodiment,
FIG. 9 shows an enlarged cross section taken along the line IX-IX. In this embodiment, the magnetic core 9 has four branches protruding from a ring-shaped common magnetic path toward the ring center at an angle of 90 degrees to each other, and the tips of these branches are connected to the magnetic pole tips. 9a to 9d are substantially in contact with the outer surface of the heat insulating collar 13. Electric coils 10a to 10d are wound around the bases of the four branches, respectively. In this embodiment, the outer electrode nozzle 11n imparts a conical motion to the plasma arc current, so it is formed in the shape of a truncated cone. Other structures are the first
The structure is similar to that of the embodiment.

In this second embodiment, as shown in FIG. 11, electric coils 10a, 10c and electric coils 10b, 10d
For example, (A) in FIG.
, then (B), then (C), then (D), and again (
In the manner returning to A), the magnetic field rotates in the space surrounded by the tip surfaces of the magnetic tips 9a to 9d. That is, the electric coil 10a
By energizing the electric coil 10c in the positive direction to magnetize the pole tip 9a to the N pole, and by energizing the electric coil 10c in the reverse direction to magnetize the pole tip 9c to the S pole, the magnetic A magnetic flux Mf flows from the pole tips 9a to 9c, and the plasma arc current receives a force in the direction F from the pole tips 9b to 9d, as shown in FIG. 10(A), and is deflected in the same direction F. Next, the electric coil 10d is energized in the forward direction to magnetize the magnetic pole tip 9d to the N pole, and the electric coil 10b is energized in the reverse direction to magnetize the magnetic pole tip 9d.
By magnetizing b to the S pole, a magnetic flux Mf flows from the magnetic pole tip 9d to 9b as shown in FIG. 10(B), and the plasma arc current becomes magnetic as shown in FIG. Extreme 9
It receives a force in the direction F from a to 9c and is deflected in the same direction F. Next, the electric coil 10c is energized in the forward direction to magnetize the magnetic pole tip 9c to the north pole, and the electric coil 10a is energized in the reverse direction to magnetize the magnetic pole tip 9a to the south pole.
As shown in (C), magnetic flux Mf flows from the magnetic pole tip 9c to 9a.
flows, and the plasma arc current receives a force in the direction F from the pole tip 9d toward the pole tip 9b, as shown in FIG. 10(C), and is deflected in the same direction F. Next, the electric coil 10b is energized in the positive direction to magnetize the magnetic pole tip 9b to the N pole, and the electric coil 1
By applying electricity in the reverse direction to 0d to magnetize the pole tip 9b to the S pole, a magnetic flux Mf flows from the pole tip 9b to 9d as shown in FIG. 10(D), and the plasma arc current is
As shown in (D), a force is applied in the direction F from the magnetic pole tip 9c toward 9a, and the magnetic pole tip is deflected in the same direction F.

In pulse energization as shown in FIG. 11(A), the plasma arc current is as shown in FIG. 10(A) and (B).
), (C), and (D), and stay at each position for a relatively long time, but the movement between each position is rapid, resulting in an inuniform movement that draws a rectangular shape. The energization stop time of each electric coil is zero or extremely short, and during the forward and reverse energization period of one set of electric coils (for example, 10a and 10c) (
For example, at the midpoint of the energization period), another set of electric coils (
10b, 10c), when the energization cycle and energization phase difference are made small in the mode of starting forward and reverse energization, the plasma arc current becomes as shown in FIG. 12 (A), (AB), (B), (BC
), (C), (CD), (D) and (DA), the movement between each position is rapid and each position stays relatively long, inconstant motion depicting an octagon. becomes. This inconstant motion that draws an octagon is close to circular motion, and the above-mentioned 4
The movement is smoother than the non-uniform movement that draws a rectangular shape, and there is less fluctuation of the tip frame due to deflection movement of the plasma arc current.

In a preferred embodiment of the present invention, in order to make the deflection motion of the plasma arc current a smoother circular motion,
A sinusoidal alternating current is applied to each of the electric coils 10a to 10d, as shown in FIG. 11(B). That is,
An AC voltage of a required level is applied to the electric coil 10a, and an AC voltage whose phase is delayed by 270 degrees is applied to the electric coil 10b, and an AC voltage whose phase is delayed by 180 degrees is applied to the electric coil 10c with respect to the AC voltage applied to the electric coil 10. An AC voltage with a phase delay of 90 degrees is applied to the electric coil 10d. As a result, a substantially perfect uniform circular motion magnetic field is generated in the space surrounded by the tip surfaces of the magnetic pole tips 9a to 9d, and the plasma arc current moves uniformly in a circular motion. Therefore, the motion of the plasma arc current is smooth, and the plasma arc current frame does not fluctuate due to the motion. Furthermore, heating of the surface of the metal material within the scanning width of the plasma arc current becomes more uniform.

[0036]

[Effects] The plasma jet torch of the first invention of the present application is a non-transfer type torch in which an electric coil for generating magnetic flux is installed inside the torch, and an arc current for generating a plasma jet is provided. It is very efficient because magnetic flux is applied directly, and reliable rocking can be obtained with a small amount of magnetic flux. The heat resistance of electric coils has been sufficiently improved.

[0037] In the method for swinging a non-moving plasma jet according to the second invention of the present application, the effects of the above-mentioned first invention are similarly brought about, and the magnetic pole tips (9a, 9b,
9c, 9d) and two or more pairs of electric coils (10a, 10
b, 10c, 10d), and each of the electric coils (10a, 10b, 10c, 10d) has a rotating magnetic field in the space surrounded by the tip of the magnetic pole tip (9a, 9b, 9c, 9d). Since a sinusoidal alternating voltage is applied that produces The plasma arc current draws a cone between the tip of the electrode (1) and the metal material. Electric coil (10a, 10b, 10c, 10d
) is a sine wave, and the circular motion is substantially uniform circular motion, so the movement of the plasma arc current is very smooth and its shape is stable, and no flaking due to deflection motion occurs.
Virtually no wave fluctuation occurs.

[Brief explanation of the drawing]

1 is a longitudinal sectional view of a first embodiment of the first invention of the present application, and is a sectional view taken along line II in FIG. 2;

2 is a plan view showing the lower surface of the plasma jet torch shown in FIG. 1. FIG.

3 is a longitudinal cross-sectional view of a portion of the plasma jet torch shown in FIG. 1, showing deflected plasma arc current; FIG.

4 is a graph showing the relationship between the magnetic flux density between the magnetic pole tips and the arc deflection angle of the plasma arc current of the plasma jet torch shown in FIG. 3. FIG.

5 is a reduced plan view showing magnetic flux density measurement points of the plasma jet torch shown in FIG. 2; FIG.

6 is a graph showing the relationship between the electric coil current value and the magnetic flux density at the magnetic flux density measurement points shown in FIG. 5. FIG.

7 is a time chart showing the waveform of the current flowing through the electric coil 10 of the plasma jet torch shown in FIG. 1. FIG.

FIG. 8 is a plan view showing the bottom surface of the second embodiment of the invention No. 1 of the present application.

9 is an enlarged sectional view taken along the line IX-IX in FIG. 8. FIG.

[FIG. 10] Electric coil 10 of the second embodiment shown in FIG. 8
FIG. 12 is a plan view showing the direction Mf of magnetic flux generated between the magnetic pole tips when the current shown in FIG. 11 (A) is passed between a to 10d.

[FIG. 11] Electric coil 10 of the second embodiment shown in FIG. 8
It is a time chart showing the waveform of the current flowing through the electric coils a to 10d, and (B) in the figure shows the waveform of the current flowing through the electric coil in an embodiment of the second invention of the present application.

[FIG. 12] Electric coil 10 of the second embodiment shown in FIG. 8
FIG. 12A is a plan view showing the direction Mf of magnetic flux generated between the magnetic pole tips when the current shown in FIG. 11B is applied to a to 10d, and FIG. 12(AB) shows the timing ab shown in FIG. 11(B), and FIG. 12(B) shows the timing ab shown in FIG.
12 (BC) shows the timing bc shown in FIG. 11 (B).
12(C) is the timing c shown in FIG. 11(B), FIG. 12(CD) is the timing cd shown in FIG. 11(B), and FIG. 12(D) is the timing cd shown in FIG. (DA) in FIG. 12 is for timing d shown in (B), and (DA) in FIG.
The timing da shown in B) is shown.

[Explanation of symbols]

1: Electrode 2: Chuck 3: Cap 4: Electrode stand 5: Backbone 6: Inner nozzle member 6n: Inner nozzle 7: Centering stone 8: Outer nozzle member 8n: Outer nozzle 9: Magnetic core 9a to 9d: Magnetic Extreme 10, 10a-10d: Electric coil
11: Outer electrode 11n: Outer electrode nozzle 12: Coil lead 12a, 12b: Terminal

Claims (2)

[Claims] 1. An electrode, an inner nozzle member having a plasma nozzle at a position opposite to the tip of the electrode, a gas flow path for supplying gas to a space between the inner nozzle member and the electrode, and a plasma A non-transfer type plasma jet torch having an outer electrode member having a plasma exit opening at a position facing the nozzle, which is inserted between the inner nozzle member and the outer electrode member, and is connected to the plasma exit opening from the plasma nozzle. an insulated cylinder surrounding the advancing plasma flow path; and an electric coil for generating magnetic flux across the insulated cylinder;
A non-transfer type plasma jet torch characterized by comprising: 2. An electrode, an inner nozzle member having a plasma nozzle at a position facing the tip of the electrode, a gas flow path for supplying gas to a space between the inner nozzle member and the electrode, and a gas flow path for supplying gas to the plasma nozzle. an outer electrode member having plasma exit openings at opposing positions; a heat insulating cylindrical body inserted between the inner nozzle member and the outer electrode member and surrounding a plasma flow path that advances from the plasma nozzle to the plasma exit opening; a magnetic core having two or more pairs of magnetic pole tips facing the outer surface of the heat insulating cylinder and facing each other with the heat insulating cylinder placed therebetween, and the magnetic cores being wound around the magnetic core and opposing each other. A plasma jet torch is provided with a plurality of electric coils for generating a magnetic flux that crosses the heat insulating cylinder between them, and each of the electric coils generates a rotating magnetic field in a space surrounded by a tip of the pole tip. A non-transfer type plasma jet oscillation method characterized by applying a sinusoidal alternating voltage.