JPH0621553B2 - Fusuko corona generator - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a corona generating device used for cleaning automobile exhaust gas by corona discharge and the like, and particularly, to generate a payer corona discharge stably. The present invention relates to a futon corona generator.

[Conventional technology]

Conventionally, as this type of technology, there is one disclosed in Japanese Patent Laid-Open No. 57-20510. According to the related art, the corrugated cylindrical dust collecting tube is composed of a desired number of discharge wires stretched in the hollow portion of the cylindrical dust collecting cylinder, and a high voltage is applied to the discharge wire. Was applied to remove dust such as tar particles and fine particles of graphite in the exhaust gas. That is, the particles floating in the exhaust gas are attracted and adhered to the inner wall of the dust collecting cylinder by the action of the strong electrostatic field generated between the cylindrical dust collecting cylinder and the discharge line,
It was designed to remove dust.

[Problems to be solved by the invention]

However, according to the above-mentioned conventional technique, there is a risk that the discharge wire is broken when a spark discharge occurs between the dust collecting tube and the discharge wire.

Further, the suction adhesion is weak and insufficient to remove harmful gases such as NO _X and CO _X in the exhaust gas.

As a possible discharge generation mode that activates and dissociates and removes such harmful gas, a corona discharge has been considered recently, but in a general corona discharge phenomenon, the suction force of dust and the like contained in exhaust gas and The desired value for dissociation power could not be secured.

However, in order to put into practical use the technique of dissociating and removing harmful gas by the corona discharge, it is necessary to generate a peculiar corona, that is, a payer corona, and it is necessary to secure an increase in the number of payer coronas.

[Means for solving problems]

An object of the present invention is to solve the above-mentioned problems and to stably generate a large-scaled paying corona discharge over a wide range that is sufficient for cleaning exhaust gas.

In order to achieve the above-mentioned object, the present invention is a brush corona generating device mounted on an exhaust gas pipe of an automobile for cleaning exhaust gas, comprising a conductor having spiral protrusions formed on its surface. A first electrode, a second electrode made of a conductor provided to face the first electrode, an insulating layer deposited on the second electrode surface, the first electrode and the second electrode There is provided a breaker corona generating device comprising: a high voltage alternating power source connected between electrodes.

[Work]

 The present invention having the above-described structure operates as follows.

That is, when a high voltage is applied between the first electrode and the second electrode by the high-voltage alternating power supply, a brush corona is generated between the first electrode and the insulating layer adhered to the inner surface of the second electrode.

This state is shown in FIGS. 5 to 7, which will be described below.

FIG. 5 shows a state where a positive voltage is applied to the first electrode 1 and a negative voltage is applied to the second electrode 2 by the high voltage alternating power source 4.

The arrow indicated by EO in FIG. 5 indicates the direction of the electric field generated by the high voltage applied between the first electrode 1 and the second electrode 2, and the arrow indicated by ES accumulates on the surface of the insulating layer 3. The direction of the reverse electric field generated by the generated electric charge is shown, P shows the positive electric charge accumulated on the surface of the insulating layer 3, C1 shows the positive corona, and here, in particular, the cornice corona in which the positive corona grows most.

In the state shown in FIG. 5, the payoff corona C1 is generated and the positive charge P is accumulated on the surface of the insulating layer 3, and the reverse electric field ES increases according to the amount of the plus charge P to suppress the payoff corona C1. , The brush corona C1 changes and decays into a brush corona or a film corona that occurs only near the first electrode 1.

The change attenuation phenomenon of the payout corona C1 is caused because the accumulated amount of the positive charge P becomes too large.
By taking measures to reduce this excessive positive charge P, the payer corona C1 can be increased and grown.

In the present invention, the generation of the payout corona C1 is ensured by neutralizing and reducing the excessive positive charge P through the steps shown in FIGS. 6 and 7 which will be described later.

FIG. 6 shows a so-called zero state in which the polarity of the output of the high voltage alternating power source 4 is switched. In the state shown in FIG. 6, the generation of corona is temporarily stopped. FIG. 7 shows a state in which a negative voltage is applied to the first electrode 1 and a positive voltage is applied to the second electrode 2 by the high-voltage alternating power supply 4 in a polarity opposite to that shown in FIG. Indicates.

In FIG. 7, e represents an electron and C2 represents a negative corona.

In the state shown in FIG. 7, the negative electrode corona C2 and the electron e are generated from the first electrode 1, and the electron e is combined with the positive charge P accumulated on the surface of the insulating layer 3 and neutralized.

As a result, the excess positive charge P is reduced, and when the state again shown in FIG. 5 is reached, the paying corona C1 can be generated.

As described above, by repeating the state shown in FIGS. 5 to 7, the continuous generation of the brush corona C1 can be maintained and ensured.

〔Example〕

In this embodiment, an embodiment in which the present invention is applied as a dissociation / removal device for harmful gas in automobile exhaust gas will be described.

FIG. 1 shows a vertical cross section of a shoveling corona generating device 5 according to the invention formed in an exhaust gas pipe.

The first electrode 1 is formed by spirally forming a spiral convex portion on the surface thereof, and is processed into, for example, a shape in which a stainless rod is threaded. The processing of the threaded shape may be appropriately selected from a method of using a cutting machine such as a milling machine and a method of using a die processing machine such as sintering. Further, by changing the thread pitch of the thread, a convex portion 11 having a triangular sectional shape on the surface of the first electrode 1 as shown in FIG. 2 or a convex portion having a trapezoidal sectional shape as shown in FIG. 1
1 can be formed.

The first electrode 1 is supported at the center of an insulating layer 3 formed in a cylindrical shape by a support 6 made of an insulating material and made of a material made of, for example, ceramics or organic glass.

A second electrode 2 is formed on the outside of the insulating layer 3 by deposition.

As the forming procedure, for example, first, a metal paste is printed on the surface of an insulating layer 3 such as ceramics and fired to form the second electrode 2, or the second electrode 2 is previously formed with a metal pipe, and then The surface of the second electrode 2 is enameled with organic glass or the like to form the insulating layer 3.
Note that a simple combination of an insulating pipe and a metal pipe may be used.

The first electrode 1 and the second electrode 2 have a high voltage alternating power supply 4
It is electrically connected via. The high voltage alternating power source 4 is
It is a circuit that generates positive and negative high voltage at a certain frequency,
The waveform may be a sine wave, a pulse wave, or the like. The frequency may be constant or may be a frequency synchronized with the engine speed such as the ignition coil output.

As shown in FIG. 4, the shoveling corona generating device 5 configured as described above is interposed in the path of the exhaust gas pipe 9 connecting the engine 7 and the silencer 8.

Further, the payout corona generating device 5 and the silencer 8 may be integrated.

Thus, in the space formed by the first electrode 1 and the insulating layer 3 of the corona generating device 5, a large-scale brush carrier corona C1 can be stably maintained and generated, and when exhaust gas passes through this, NO _X
And toxic gases CO _X, etc. are activated by the action of hossu corona and dust or dissociated changed to other purified gas or water, it can be prevented the emission of noxious gases into the atmosphere.

According to the experiment of the inventor, the high-voltage alternating-current power supply 4 shown in FIG. 1 boosts the alternating current having a frequency of 50 Hz to about 10 to 15 Kv,
When a voltage was applied between the first electrode 1 and the second electrode 2, a large-scale fusing corona discharge phenomenon was induced and observed over a wide range. It was also confirmed that the obtained child-bearing corona could be stably maintained and secured without being attenuated.

In the above-mentioned embodiment, the continuous convex portion 11 is formed on the surface of the first electrode 1 by a threaded shape.
This is for generating the brush corona C1 in a wide range as shown in FIG. 1, and may have another shape, for example, a projection provided on a key portion of the surface of the first electrode 1.

[Effect]

According to the present invention, since the spiral convex portion is formed on the surface of the first electrode in a spiral manner, the payout corona discharge can be continuously generated in a spiral shape, and a large-scale payout corona discharge is generated over a wide range. Can be made.

Therefore, a sufficient value can be secured for the suction force and the dissociation force of dust and the like contained in the exhaust gas, and the harmful gas dissociation removal technique by the payer corona discharge can be put into practical use.

Further, when the spiral convex portion is formed as a screw thread, the shape can be easily formed by using a general processing technique such as cutting or sintering.

Furthermore, by appropriately changing the pitch of the threads,
This is an effect that the cross-sectional shape of the convex portion can be triangular or trapezoidal, and the generation density of corona discharge can be arbitrarily set.

Furthermore, by mounting the brush-corona generating device according to the present invention on the exhaust gas pipe of an automobile, it is possible to purify harmful gas in the exhaust gas and contribute to the prevention of environmental pollution. .

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a preferred embodiment of the present invention. FIG. 2 is a perspective view of a main part in which a convex portion having a triangular cross section is formed on the surface of the first electrode 1 shown in FIG. FIG. 3 is a perspective view of a main portion in which a convex portion having a trapezoidal cross section is formed on the surface of the first electrode shown in FIG. FIG. 4 is an explanatory diagram showing a state in which the brush corona generating device shown in FIG. 1 is interposed in an exhaust gas pipe of an automobile. 5 to 7 are schematic diagrams for explaining the corona generation state of the present invention, FIG. 5 is a diagram showing a positive corona generation state, and FIG. 6 is a diagram showing a zero point state, FIG. 7 is a diagram showing the state of negative corona generation. 1 ... first electrode, 2 ... second electrode, 3 ... insulating layer,
4 ... High-voltage alternating power source, 5 ... Pastry corona generator, 6 ...
… Supporting equipment, 7 …… Engine, 8 …… Silencer, 9 …… Exhaust pipe, 11 …… Convex part.

Claims (2)

[Claims] 1. A brush corona generating device mounted on an exhaust gas pipe of an automobile for cleaning exhaust gas, comprising: a conductor made of a conductor having spiral projections formed on its surface.
Electrode, a second electrode made of a conductor provided so as to face the first electrode, an insulating layer adhered to the second electrode surface, and the first electrode and the second electrode. A breaker corona generating device comprising: a high-voltage alternating power supply connected in between. 2. A brush corona generating device according to claim 1, wherein the spiral convex portion formed on the first electrode comprises a thread formed by thread cutting.