JP2002203521A - Ultraviolet ray generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultraviolet ray generator having a high luminous efficiency while using a lower amount of electric power consumption. SOLUTION: This ultraviolet ray generator is equipped with a dielectric body container 1 which is hollow inside and composed of dielectric bodies transpermeating ultraviolet rays, plural electrodes 2 arranged outer side of this container 1, an alternating current electric power supply 3 applying an alternating current voltage to the respective electrodes 2, and an electric wire 4 connecting the alternating current power supply 3 and the electrodes 2. Electricity is discharged in the dielectric body container 1 by an application of the alternating voltage to the electrodes 2 via the electric wire 4, and ultraviolet light is generated. This ultraviolet light is irradiated outside through a space of the electrodes 2 mutually adjacent. Because the electrodes 2 with not less than 70% of an opening rate are arranged outside of the dielectric body container 1 and a high-frequency voltage is applied to these electrodes 2, the ultraviolet light can be efficiently emitted from the space between the electrodes 2, and a sterilization of a sewage or the like can be carried out at a low cost and in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sterilizing apparatus using a gas discharge device such as an ultraviolet lamp which generates ultraviolet light by electrodeless discharge using a discharge gas containing a rare gas as a main component and a halogen gas or mercury added thereto. In particular, it targets sterilization, disinfection, and decolorization of water and sewage, deodorization and decolorization of industrial water, bleaching of pulp, and sterilization of medical equipment.

[0002]

2. Description of the Related Art Ultraviolet light has been conventionally used for the purpose of sterilizing, disinfecting, and decolorizing water and sewage. As a light source that generates ultraviolet light, there are a mercury lamp, an excimer lamp, and the like. Low-pressure mercury lamps have wavelengths of 254 nm or 185 nm
Of ultraviolet light. Excimer lamps using xenon, krypton, and argon as excitation media generate ultraviolet light having wavelengths of 172 nm, 146 nm, and 126 nm, respectively.

[0003]

A conventional sterilizer for generating ultraviolet light is a low-pressure mercury lamp (having a mercury wavelength of 25%).
4 nm). The reason is that it is suitable for cutting bacterial DNA.

[0004] Conventional mercury lamps include an electroded lamp in which an electrode is in contact with a discharge gas and an electrodeless lamp in which an electrode is not in contact with a discharge gas. Electrode lamps have a problem in that the life of the lamp is shortened due to deterioration of the discharge gas, wear of the electrodes, or adhesion of worn electrode parts to the inner wall of the lamp. The life of the lamp is about 10,000 hours. This is the upper limit.

[0005] On the other hand, the electrodeless lamp has a problem that the utilization efficiency of ultraviolet light is poor because the external electrode does not transmit ultraviolet light. Further, when an AC voltage (high frequency of 100 kHz or more) is applied to the external electrode to turn on the lamp, if the installation accuracy of the external electrode is low, the lamp may not be turned on properly due to a different discharge impedance.

[0006] Further, in the electrodeless lamp, since the electrodes are provided outside, there is a possibility that an inrush current flows due to a wiring error or water leakage and the like, and an inrush current flows, thereby destroying the power supply.

Further, when an electroded lamp or an electrodeless lamp is turned on using an AC power supply having a frequency of 100 kHz or more,
If the wire connecting the power supply and the lamp exceeds a certain length, the lamp may not be lit normally due to impedance mismatch. In particular, if there is a large difference between the AC frequency of the power supply and the resonance frequency of the discharge unit, power cannot be used effectively due to the relationship between the output impedance and the discharge impedance of the power supply.

In the case of an ultraviolet lamp which is turned on by passing an alternating current, the voltage applied to the electric wire increases as the amount of power supply increases, so that the withstand voltage is increased.
The wires must be thick. For this reason, it is difficult to route the electric wires, and there is a possibility that the lamp cannot be moved freely.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ultraviolet ray generator having low power consumption and high luminous efficiency.

[0010]

In order to solve the above-mentioned problems, the invention according to claim 1 comprises a plurality of electrodes disposed outside a dielectric container which can transmit ultraviolet rays, and an AC voltage or an AC voltage applied to the electrodes. A power supply for applying a pulse voltage, and applying an AC voltage or a pulse voltage to the electrodes, thereby causing a discharge inside the dielectric container to emit ultraviolet light, and The container is a hollow cylindrical container filled with a discharge gas, and emits ultraviolet light from between the adjacent electrodes.

Since a plurality of electrodes are arranged outside the dielectric container and ultraviolet light is emitted from the dielectric container, the ball does not break.

It is desirable that the plurality of electrodes be arranged so as to have an aperture ratio of 70% or more.

If at least a part of the surface of the electrode facing the dielectric container is formed of a material that reflects ultraviolet light or is processed into a shape capable of reflecting ultraviolet light, the luminous efficiency of ultraviolet light can be increased.

[0014] By baking a metal on the surface of the dielectric container to form an electrode, or by printing the electrode on the surface of the dielectric container, it is possible to improve the accuracy of the installation position of the electrode, and the variation in discharge impedance due to manufacturing. Can be suppressed.

A coil electrode is wound around the outer peripheral surface of the dielectric container, and a capacitor is provided between one end of the coil electrode and a ground terminal.
Since the coil and the power supply are connected in series, even if the coil electrode is short-circuited due to a wiring error, water leakage, or the like, a rush current can be prevented by the capacitor.

One of the electric wires is connected to the power supply at one end of the cylindrical container, and the other electric wire is connected to the ground terminal at the other end of the cylindrical container. Variation in light brightness can be suppressed.

The AC frequency f _OSC of the power supply is adjusted so that the AC frequency f _{OSC of the} power supply and the resonance frequency f _Z of the discharge part of the dielectric container satisfy the relationship of 1.1 f _OSC > f _Z > 0.9f _OSC. Accordingly, signal reflection is less likely to occur, and the luminous efficiency of ultraviolet light can be improved.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ultraviolet ray generator according to the present invention will be specifically described with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a first embodiment of an electrodeless discharge lamp which is an ultraviolet ray generator according to the present invention. The electrodeless discharge lamp 10 shown in FIG. 1 includes a dielectric container 1 made of a dielectric material having a hollow inside and transmitting ultraviolet light, a plurality of electrodes 2 disposed outside the container 1, and an AC voltage applied to each electrode 2. AC power supply 3 to be applied, AC power supply 3 and electrode 2
And an electric wire 4 for connecting

When an AC voltage is applied to the electrode 2 through the electric wire 4, a discharge occurs inside the dielectric container 1,
Ultraviolet light is generated. This ultraviolet light is applied to the adjacent electrode 2
Radiated to the outside through the space.

The size of the electrode 2 is set so that the aperture ratio is 70% or more in order to increase the efficiency of using ultraviolet light. At least a part of the surface of the electrode 2 on the side opposed to the dielectric container 1 is mirror-finished with a material that reflects ultraviolet light. By such mirror finishing, the luminous efficiency of ultraviolet light can be further increased.

In FIG. 1, the dielectric container 1 and the electrode 2 are separate members, but the electrode 2 may be formed by printing or printing a metal on the surface of the dielectric container 1. Thereby, the mounting accuracy of the electrode 2 is improved, and variation in the brightness of the ultraviolet light due to manufacturing can be suppressed.

The effective length of the electric wire 4 is set so as to be 1/8 wavelength or less of the power supply frequency. Number of electric wires 4 N
Is set to satisfy the condition (1), where P is the supplied power and Z is the characteristic impedance of the electric wire 4.

[Equation 1] 300> √ (PZ / N) (1) The reason why the condition of the expression (1) is obtained will be described below. FIG.
Are the frequency (MHz) and attenuation (dB / k) of the high-frequency coaxial cable.
FIG. 3 is a diagram showing a relationship between m) and power capacity (W). The electrodeless discharge lamp 10 used for sewage treatment requires a withstand voltage of about 1000 V.
When a high-frequency coaxial cable that can be used at a power supply frequency of 15 MHz with a power capacity of 00 W is searched from FIG. 2, it is found that a high-frequency coaxial cable called 8D-2V is applicable.

The electric wire 4 having a higher withstand voltage than 8D-2V may be used. However, since the diameter of the electric wire 4 is large, it is difficult to route the electric wire 4, and the lamp shown in FIG. become unable. That is, the workability is deteriorated, which is not preferable.

FIG. 3 shows the characteristics of the high-frequency coaxial cable called 8D-2V described above. As can be seen from this figure, 8D-2V has a withstand voltage of 1000V. Actually, a voltage of about 1/3 of the withstand voltage is applied to the cable, so that a voltage of about 300 V is approximately applied to the cable.

The right side of the equation (1) indicates the voltage actually applied to the electric wire 4. Therefore, the right side is 300
If it is smaller than V, it will operate stably for a long period of time. Therefore, in the present embodiment, the number N of the electric wires 4 is determined so as to satisfy the condition of the above equation (1).

The length of the electric wire 4 in FIG.
In the case of 1/8 wavelength or more, a matching device that matches the output impedance of the power supply 3, the discharge impedance of the lamp 10, and the characteristic impedance of the cable is required. Without a matcher, signal reflection would occur and power loss would increase. Therefore, in the present embodiment, the effective length of the electric wire 4 is set to be equal to or less than 1/8 wavelength of the power supply frequency so that a matching device is not required.

FIG. 4 is a sectional view of a processing unit 11 incorporating the electrodeless discharge lamp 10 of FIG. As shown,
The dielectric container 1 and the electrode 2 of FIG. 1 are housed in a protective container 12 and are sealed by a metal flange 13. Accordingly, it is possible to prevent an accident that a worker receives an electric shock to the electrode 2, prevent the electrode 2 from getting wet with water, and prevent an electric leakage or the like.

The protection container 12 is further incorporated in the processing unit 11. Between the outer wall of the processing unit 11 and the outer wall of the protective container 12, a path 14 through which a fluid to be sterilized or the like flows is provided. This fluid flows into the processing unit 11 from the inlet 15 of the processing unit 11 and is discharged to the outside of the processing unit 11 from the outlet 16 through the periphery of the lamp in FIG. While the fluid passes around the lamp of FIG. 1, ultraviolet light emitted from the lamp impinges on the fluid and is sterilized or the like.

The processing unit 11 shown in FIG. 4 is for sterilizing, disinfecting, and decolorizing water and sewage, deodorizing and decolorizing industrial water, bleaching pulp, or sterilizing medical equipment. Further, the fluid flowing into the processing unit 11 from the inlet 15 may include not only liquid but also gas and solid.

The processing unit 11 shown in FIG. 2 is provided with only one electrodeless discharge lamp 10 shown in FIG. 1, but as shown in FIG.
Batch processing may be performed.

As described above, in the first embodiment, since the electrode 2 having an aperture ratio of 70% or more is arranged outside the dielectric container 1 and a high-frequency voltage is applied to the electrode 2, the efficiency between the electrodes 2 is reduced. It can emit ultraviolet light well, and can sterilize a sewer at low cost and in a short time.

Further, since the number N of the electric wires 4 is set so as to satisfy the condition of the above equation (1), the thickness of the electric wires 4 does not need to be too large, and the handling of the processing unit 11 becomes easy. Workability is improved.

Further, the effective length of the wire 4 is
Since the wavelength is set to 1/8 wavelength or less, signal reflection does not occur without providing a matching unit for impedance matching, and the entire device can be reduced in size and cost.

(Second Embodiment) The second embodiment is characterized in that a coil-shaped electrode 2 is provided.

FIG. 6 is a diagram showing a schematic configuration of a second embodiment of the electrodeless discharge lamp 10, which is an ultraviolet generator according to the present invention. The electrodeless discharge lamp 10 of FIG. 6 includes a dielectric container 1 made of a dielectric having a hollow inside and transmitting ultraviolet light,
A coil-shaped electrode 2 wound around the outer peripheral surface of the container
(Hereinafter, a coil electrode). A capacitor C1 and a coil L are provided between one end of the coil electrode 2 and the ground terminal.
1, an electric wire 4 and a power supply 3 are connected in series, and a coil electrode 2
Is grounded.

The high frequency voltage from the power source 3 causes the coil L1
A high-frequency current flows through the device, and a magnetic field is generated by the principle of an electromagnet.
This magnetic field causes an eddy electric field inside the dielectric container 1 to generate a donut-shaped discharge ring, and ultraviolet rays effective for sterilization are emitted.

The capacitor C1 is for preventing an inrush current from flowing when the coil electrode 2 is short-circuited, and is not always an essential component.

Although the electrodeless discharge lamp 10 shown in FIG. 6 is omitted in the drawing, the entire lamp is sealed and sterilization and the like are performed so that the coil electrode 2 does not come into contact with the fluid.

In the second embodiment, the AC frequency f
_OSC and the resonance frequency f _Z of the discharge portion of the dielectric container 1 is to be substantially equal. Specifically, 1.1f _OSC > f _Z >
The relationship of 0.9f _OSC is satisfied. This makes it difficult for power loss due to signal reflection to occur,
It can emit high energy ultraviolet light with low power consumption.

To adjust so as to satisfy the above conditions,
For example, it is conceivable to variably control the AC frequency f _OSC of the power supply 3. Alternatively, the resonance frequency f _Z by changing the inductance of the capacitor and the coil L1 of the capacitor C1 in FIG. 6
May be variably controlled.

As described above, in the second embodiment, since the coil electrode 2 is provided on the outer peripheral surface of the dielectric container 1 to emit ultraviolet light, the aperture ratio can be set wider than in the first embodiment. Also, the AC frequency f _OSC of the power supply 3 and the dielectric container 1
To adjust the resonance frequency f _Z of the discharge portion such that substantially equal, power consumption can be reduced.

Incidentally, the coil electrode 2 does not necessarily need to be spirally wound around the dielectric container 1. For example,
FIG. 7 is a diagram illustrating an example in which a plurality of annular coil electrodes 2 are integrally formed on two electric wires 4a and 4b extending in parallel in the axial direction of the dielectric container 1. A power supply is connected to one of the wires 4 and the other wire 4 is grounded.

Although the structure of the lamp 10 shown in FIG. 7 is simple, the intensity of the ultraviolet light is higher on the side closer to the power supply 3 and the brightness becomes uneven.

FIG. 8 shows an example in which one electric wire 4a is connected to a power supply at one end of the dielectric container 1, and the other electric wire 4b is connected to a ground terminal at the other end of the dielectric container 1. FIG. In the case of FIG. 8, substantially uniform ultraviolet light can be emitted over the entire dielectric container 1.

FIG. 9 is a diagram showing an example in which one of the two electric wires 4 extending in the axial direction of the dielectric container 1 is arranged in a U-shape with the dielectric container 1 interposed therebetween. . In addition, electric wire 4
Is connected to a coaxial cable 15.
The use of the coaxial cable 15 can suppress unnecessary radiation of radio waves. Further, since one of the electric wires 4 surrounds the dielectric container 1, unevenness in the brightness of the ultraviolet light hardly occurs.

In FIG. 9, a plurality of coaxial cables 15 may be connected. In this case, as shown in FIG. 10, the plurality of coaxial cables 15 are connected in parallel,
The core wire 5 is connected to one electric wire 4 and the ground wire is connected to the other electric wire 4. By providing the plurality of coaxial cables 15, more high-frequency current can flow through the dielectric container 1, and strong ultraviolet light can be emitted.

FIG. 10 shows a plurality of coaxial cables 15.
The power supply 3 is provided for each of them, but a plurality of coaxial cables 15 may be connected to one power supply 3 as shown in FIG.

Also in the electrodeless discharge lamp 10 shown in FIGS. 6 to 11, it is desirable to set the number N of the electric wires 4 so as to satisfy the relationship of the above equation (2).

[0051]

As described above in detail, according to the present invention, ultraviolet light is emitted from between the electrodes disposed outside the cylindrical container which is a dielectric container, so that the so-called ball break does not occur. , Longer life. The aperture ratio is 70%
Since the electrodes are arranged as described above, strong ultraviolet light can be emitted, which can be widely used for sterilization of sewerage and the like.

Further, in order to provide two electric wires extending in the axial direction of the cylindrical container and a plurality of coil electrodes surrounding the cylindrical container and connected to the two electric wires at both ends at the both ends, the cylindrical container is provided. High-energy ultraviolet light can be emitted without spirally winding the coil electrode.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a first embodiment of an electrodeless discharge lamp which is an ultraviolet ray generating device according to the present invention.

Fig. 2 Frequency (MHz) and attenuation (dB) of high-frequency coaxial cable
/ km) and power capacity (W).

FIG. 3 is a diagram showing characteristics of a high-frequency coaxial cable called 8D-2V.

FIG. 4 is a sectional view of a processing unit including the electrodeless discharge lamp of FIG. 1;

FIG. 5 is a diagram showing an example in which a plurality of electrodeless discharge lamps are provided.

FIG. 6 is a diagram showing a schematic configuration of a second embodiment of an electrodeless discharge lamp which is an ultraviolet ray generator according to the present invention.

FIG. 7 is a diagram showing an example in which a plurality of annular coil electrodes are integrally formed on two electric wires extending in parallel in the axial direction of a dielectric container.

FIG. 8 is a diagram showing an example in which one electric wire is connected to a power supply at one end of a dielectric container, and the other electric wire is connected to a ground terminal at the other end of the dielectric container.

FIG. 9 is a diagram showing an example in which one of two electric wires extending in the axial direction of the dielectric container is arranged in a U-shape with the dielectric container interposed therebetween.

FIG. 10 is a diagram showing an example in which a plurality of coaxial cables are connected in parallel, and a core wire of each coaxial cable is connected to one electric wire, and a ground wire is connected to the other electric wire.

FIG. 11 is a diagram showing a modification of FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dielectric container 2 Electrode 3 Power supply 4 Electric wire 10 Electrodeless discharge lamp 11 Processing unit 12 Protective container 13 Metal flange 15 Inlet 16 Outlet

Claims (9)

[Claims] 1. An electrode comprising: a plurality of electrodes disposed outside a dielectric container capable of transmitting ultraviolet light; and a power supply for applying an AC voltage or a pulse voltage to the electrodes. An AC voltage or a pulse voltage is applied to the electrodes. In the ultraviolet ray generating device which emits ultraviolet light by causing a discharge inside the dielectric container by applying the voltage, the dielectric container is a hollow cylindrical container filled with a discharge gas therein. An ultraviolet light generator that emits ultraviolet light between the electrodes. 2. The ultraviolet generator according to claim 1, wherein the plurality of electrodes are arranged so as to have an aperture ratio of 70% or more. 3. The apparatus according to claim 1, wherein at least a part of the surface of the electrode facing the dielectric container is formed of a material that reflects ultraviolet light, or is processed into a shape capable of reflecting ultraviolet light. Item 3. The ultraviolet generator according to Item 1 or 2. 4. The ultraviolet light according to claim 1, wherein the electrode is formed by baking a metal on the surface of the dielectric container, or is printed on the surface of the dielectric container. Generator. 5. An electrode disposed around a dielectric container capable of transmitting ultraviolet light, and a power supply for applying an AC voltage or a pulse voltage to the electrode, and applying an AC voltage or a pulse voltage to the electrode. Thereby, in the ultraviolet ray generating device that emits ultraviolet light by causing a discharge inside the dielectric container, the dielectric container is a hollow cylindrical container filled with a discharge gas therein, and the electrode is And a coil electrode wound around the outer peripheral surface of the cylindrical container, comprising: a capacitor, a coil, and a power supply connected in series between one end of the coil electrode and a ground terminal. 6. An electrode disposed around a dielectric container capable of transmitting ultraviolet light, and a power supply for applying an AC voltage or a pulse voltage to the electrode, and applying an AC voltage or a pulse voltage to the electrode. Thereby, in the ultraviolet ray generating device that causes a discharge inside the dielectric container to emit ultraviolet light, the dielectric container is a hollow cylindrical container filled with a discharge gas therein, An ultraviolet ray generator, comprising: two electric wires extending in the axial direction of the container; and a plurality of electrodes surrounding the cylindrical container and connected to the two electric wires at both ends. 7. An electrode disposed around a dielectric container capable of transmitting ultraviolet light, and a power supply for applying an AC voltage or a pulse voltage to the electrode, wherein an AC voltage or a pulse voltage is applied to the electrode. Thereby, in the ultraviolet ray generating device that causes a discharge inside the dielectric container to emit ultraviolet light, the dielectric container is a hollow cylindrical container filled with a discharge gas therein, Two electric wires extending in the axial direction of the container, and a plurality of electrodes that surround the cylindrical container and are connected to the two electric wires at both ends at the both ends. The ultraviolet ray generator, wherein one end of the container is connected to the power source, and the other electric wire is connected to a ground terminal at the other end of the cylindrical container. 8. An electrode disposed around a dielectric container capable of transmitting ultraviolet light, and a power supply for applying an AC voltage or a pulse voltage to the electrode, wherein an AC voltage or a pulse voltage is applied to the electrode. Thereby, in the ultraviolet ray generating device that emits ultraviolet light by causing a discharge inside the dielectric, the dielectric container is a hollow cylindrical container filled with a discharge gas, and the cylindrical container Two electric wires extending in the axial direction of the cylindrical container, and a plurality of electrodes surrounding the cylindrical container and connected to the two electric wires at both ends, and one of the electric wires is the dielectric container. An ultraviolet ray generator, wherein the ultraviolet ray generator is arranged in a U-shape with the photovoltaic device therebetween. 9. A capacitor connected between the electrode and the power supply, wherein the capacitor cuts off a current path so that an inrush current does not flow even if different electrodes are short-circuited. 9. The ultraviolet ray generator according to any one of 8.