JP2002110102A - Dielectric barrier discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dielectric barrier discharge lamp which can obtain a uniform light distribution in a direction of a central axis by preventing excessive variations of a distance between an internal electrode and an external electrode of an airtight container. SOLUTION: The internal electrode 2 arranged in the airtight container 1 comprises an inner feeder electrode 2a which is arranged nearly on a center axis and extended axially, and a plurality of conductive anchors 2b having a ring shape along with an interior circumference of the container 1 which is axially arranged with nearly equi-spaced and connected to the inner feeder electrode 2a. In this lamp, even if the internal feeder electrode 2a might hang down under its own weight and the like, the conductive anchors 2b could support the inner feeder electrode 2a by contacting on the interior circumference of an airtight container 1, then prevent the inner feeder electrode 2a from an excessive hanging down. As a result, this lamp can prevent the occurrence of excessive variations of a distance between the internal electrode 2 and external electrode 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric barrier discharge lamp that emits ultraviolet light by dielectric barrier discharge.

[0002]

2. Description of the Related Art As an ultraviolet lamp that emits ultraviolet light,
Various dielectric barrier discharge lamps have been proposed, for example, Japanese Patent Application Laid-Open Nos. Hei 6-310104 and Hei 7-272.
No. 692, Japanese Patent Application Laid-Open No. 7-220687 and the like, which have been conventionally known. Such a dielectric barrier discharge lamp encloses a discharge medium (excimer generation gas) for generating excimer in an airtight discharge space, and provides a pair of electrodes inside and outside the discharge space. A high voltage is applied in between to discharge. This discharge causes ultraviolet rays to be emitted from the discharge medium.

FIG. 5 is a front view showing an example of a conventional dielectric barrier discharge lamp. In FIG. 5, 101 is a cylindrical airtight container, 102 is a conductive external electrode,
103 is a conductive internal electrode; 104 is a sealing portion;
05 is a high frequency generation circuit. Xenon or the like as an excimer generating gas is sealed in the airtight container 101.

[0004] The airtight container 101 is a material that transmits ultraviolet light, and is formed of a dielectric material, for example, quartz or the like.

[0005] The external electrode 102 is spirally wound around the outer peripheral surface of the airtight container 101 and mounted. As another form of the external electrode 102, for example, a mesh-like one is used (see FIG. 6).

The internal electrode 103 is a conductive member having, for example, a coil shape, a bar shape, a linear shape, a plate shape, or the like, and is connected to a lead wire 106 fixed to a sealing portion 104.

The high-frequency generation circuit 105 includes an external electrode 102
A voltage is applied between the electrode and the internal electrode 103 to supply electric energy required for dielectric barrier discharge.

[0008] The external electrode 1 is
When a voltage is applied between the external electrode 102 and the internal electrode 103, a dielectric barrier discharge occurs between the external electrode 102 and the internal electrode 103. Due to this discharge, excimer-producing gas such as xenon sealed in the hermetic container 101 is temporarily combined into a molecular state (excimer state). Then, when returning from the molecular state to the atomic base state, ultraviolet rays with little re-absorption are emitted. This is the light emission principle of the dielectric barrier discharge lamp.

[0009]

[Problems to be Solved by the Invention] [Light Distribution from Lamp]
The internal electrode 103 may hang down due to its own weight or due to thermal expansion during lighting. When the internal electrode 103 hangs down, the distance between the internal electrode 103 and the external electrode 102 varies, and discharge is likely to occur where the distance is short, and discharge occurs where the distance is long. It becomes difficult to do. As a result, a portion where the amount of emitted ultraviolet light is large and a portion where the amount of ultraviolet light are small are formed, and the light distribution of the dielectric barrier discharge lamp varies. Due to such variations in light distribution, the degree of uniformity is reduced.

[Starting voltage, sustaining voltage] In the dielectric barrier discharge lamp illustrated in FIGS. 5 and 6, since the distance between the outer electrode 102 and the inner electrode 103 is long,
There is a problem that the starting voltage and the lighting maintenance voltage must be increased.

[Startability] In the dielectric barrier discharge lamp illustrated in FIGS. 5 and 6, the distance between the external electrode 102 and the internal electrode 103 is long, so that the time required for the discharge to start is reduced. Longer, poor startability.

[Dirt of Dielectric Barrier Discharge Lamp] As a use of the dielectric barrier discharge lamp, application to a cleaning / sterilizing lamp has been conventionally performed. This is because the wavelength of xenon, which is a luminescent substance in a dielectric barrier discharge lamp, is 1
Since it is about 72 nm, the generation of ozone is promoted due to the absorption peak of oxygen in this wavelength region, and the generated ozone decomposes organic substances adhered to the surface of the object to be processed, thereby performing cleaning and sterilization. It is.

By the way, during cleaning and sterilization, dirt from the object to be treated may adhere to the outer peripheral surface of the airtight container 101. Since the external electrode 102 is mounted on the outer peripheral surface of the airtight container 101, maintenance such as cleaning is difficult.

An object of the present invention is to prevent the distance between the internal electrode and the external electrode from being largely varied, and to prevent the light distribution in the direction of the center axis of the hermetic container from being caused due to such a variation. That is, the light distribution is made uniform.

Another object of the present invention is to keep the starting voltage and the light emission maintaining voltage low.

Another object of the present invention is to improve startability.

Another object of the present invention is to make light emission efficient,
The aim is to increase the illuminance of ultraviolet rays.

Another object of the present invention is to facilitate maintenance such as cleaning.

Another object of the present invention is to suppress the emitted ultraviolet light from being attenuated by oxygen.

Another object of the present invention is to suppress a rise in temperature due to light emission and maintain high light emission efficiency.

Another object of the present invention is to improve the handleability when used by attaching to a washing and sterilizing apparatus.

[0022]

According to a first aspect of the present invention, there is provided a dielectric barrier discharge lamp, comprising: a tubular airtight container formed of a material which transmits ultraviolet light and is a dielectric; An internal power supply electrode disposed substantially on the central axis of the airtight container and extending in the direction of the central axis thereof; and a ring-shaped electrode formed along the inner peripheral surface of the airtight container and substantially along the central axis direction of the airtight container. An internal electrode having a plurality of conductive anchors arranged at intervals and connected to the internal power supply electrode; an excimer product gas sealed in the hermetic container; and mounted on an outer periphery of the hermetic container. External electrodes;
Is provided.

Therefore, when a voltage is applied between the external electrode and the internal electrode, a dielectric barrier discharge occurs between the two electrodes. As a result, the excimer product gas sealed in the airtight container is temporarily bonded to a molecular state (excimer state), and when returning from such a molecular state to the ground state of atoms, ultraviolet light with little reabsorption is efficiently emitted. Then, the dielectric barrier discharge lamp is turned on. The wavelength range of the emitted ultraviolet light depends on the type of excimer-producing gas sealed in the airtight container. For example, when a large amount of xenon is sealed, ultraviolet light having a wavelength of 172 nm is emitted.

The internal electrode has a feeder electrode and a conductive anchor. Since the ring-shaped conductive anchor is located near the inner peripheral surface of the airtight container, the internal feeder electrode hangs down due to its own weight or the like. In the event of an attempt, the conductive anchor comes into contact with and supports the inner peripheral surface of the airtight container, so that the internal feeder electrode is prevented from drooping greatly. And, by preventing the sag, the distance between the internal electrode and the external electrode can be prevented from being largely varied, and the portion between the internal electrode and the external electrode where the discharge is likely to occur due to the large variation can be generated. It is possible to prevent the light distribution in the central axis direction of the hermetic container from becoming uneven due to the formation of a portion that is difficult to perform, and to achieve uniform light distribution. As a result, the uniformity is increased in the portion where the ultraviolet rays are irradiated.

In addition, since the conductive anchors are uniformly provided, the distance between the conductive anchor, which is a part of the internal electrode, and the inner peripheral surface of the hermetic container, which is a dielectric, is shortened. Since the relationship with the external electrode becomes uniform, creeping discharge easily occurs on the inner peripheral surface of the airtight container,
The startability can be improved, and the starting voltage and the lighting maintenance voltage can be reduced.

According to a second aspect of the present invention, in the dielectric barrier discharge lamp according to the first aspect, the internal power supply electrode is formed in a coil shape.

Therefore, even if the internal power supply electrode expands due to thermal expansion at the time of lighting, the expansion can be absorbed by forming the coil into a coil shape, thereby preventing the internal power supply electrode from sagging due to thermal expansion. it can. For this reason, it is possible to prevent the variation in the distance between the internal electrode and the external electrode caused by the drooping of the internal power supply electrode, and to reduce the variation in the light distribution in the center axis direction of the hermetic container caused by the variation. The light distribution can be uniformed.

According to the third aspect of the present invention, in the dielectric barrier discharge lamp according to the first or second aspect, the inner diameter of the hermetic container is D mm, and the outer diameter of the conductive anchor is dm.
When m, 0.3 <d / D <1.0.

Therefore, by defining the inner diameter of the hermetic container and the outer diameter of the conductive anchor to these values, a portion where discharge is likely to occur due to a variation in the distance between the internal electrode and the external electrode is generated. It is possible to prevent the generation of a portion that is unlikely to be generated, and it is possible to prevent variations in light distribution in the direction of the central axis of the airtight container, thereby achieving uniform light distribution.

According to a fourth aspect of the present invention, in the dielectric barrier discharge lamp according to the first or second aspect, the inner diameter of the hermetic container is D mm, and the outer diameter of the conductive anchor is d.
mm and D> 20 mm, 5 mm <d <D.

Therefore, the inner diameter of the airtight container is 20 m.
Even in the case of a thick type dielectric barrier discharge lamp having a diameter of at least m, the variation in the distance between the internal electrode and the external electrode can be achieved by defining the inner diameter of the airtight container and the outer diameter of the conductive anchor to such values. Accordingly, it is possible to prevent a portion in which discharge easily occurs and a portion in which discharge is unlikely to be generated, and to prevent variation in light distribution in the central axis direction of the airtight container, thereby achieving uniform light distribution.

The invention according to claim 5 is the invention according to claims 1 to 4
The dielectric barrier discharge lamp according to any one of the above,
The angle θ of the conductive anchor with respect to the internal feeder electrode is 80 to 90 °.

Accordingly, the distance between the conductive anchor, which is a part of the internal electrode, and the inner peripheral surface of the hermetic container, which is a dielectric, is reduced, and the position of the conductive anchor is regulated. Creepage discharge can be generated stably on the peripheral surface, and the stable creepage discharge prevents variations in light distribution in the central axis direction of the hermetic container, and achieves uniform light distribution. it can.

[0034] The invention according to claim 6 is the invention according to claims 1 to 5.
The dielectric barrier discharge lamp according to any one of the above,
The excimer product gas is sealed in the hermetic container at a pressure of 133 to 1013 Pa.

Therefore, by setting the pressure of the excimer-producing gas to such a high value, the molecular weight of the excimer-producing gas in the hermetic container increases, creeping discharge occurs efficiently, startability is improved, and ultraviolet light is emitted. Is performed efficiently.

The invention according to claim 7 is the invention according to claims 1 to 6
The dielectric barrier discharge lamp according to any one of the above,
And a tubular outer tube formed of a UV-permeable material surrounding the airtight container.

Therefore, since the airtight container is covered with the outer tube, even when the dielectric barrier discharge lamp is used for cleaning and sterilizing, dirt from the object to be treated adheres to the outer peripheral surface of the outer tube. It does not adhere to the external electrode mounted on the outer peripheral surface of the hermetic container. Therefore, maintenance such as cleaning of the dielectric barrier discharge lamp can be easily performed. further,
The metal ions released from the external electrodes can be prevented from adhering to the object.

According to an eighth aspect of the present invention, in the dielectric barrier discharge lamp according to the seventh aspect, a flow serving as a flow path of an inert gas is provided between an outer peripheral surface of the hermetic container and an inner peripheral surface of the outer tube. A road space is formed.

Therefore, by flowing an inert gas, such as nitrogen gas or argon gas, into the flow path space, oxygen (oxygen contained in the atmosphere) is removed from the flow path space, and dielectric barrier discharge is performed. The lamp can be cooled.

By removing oxygen, it is possible to prevent ultraviolet rays transmitted through the airtight container from being attenuated by oxygen when traveling in the flow path space.

Further, by the cooling action of the inert gas, a decrease in the luminous efficiency of ultraviolet rays due to a rise in temperature can be prevented, and a high luminous efficiency can be maintained.

According to a ninth aspect of the present invention, in the dielectric barrier discharge lamp of the seventh or eighth aspect, sockets are provided at both ends of the outer tube, and one of the sockets is connected to a lead wire of the external electrode. ing.

Therefore, when the dielectric barrier discharge lamp is used by attaching it to a washing and disinfecting device, it can be grounded, for example, by contacting the socket, to which the external electrodes are conducted, with a conductive member such as the washing and disinfecting device. In addition, the wiring structure of the external electrodes is simplified, and the handleability when the dielectric barrier discharge lamp is attached to and detached from the cleaning / sterilizing apparatus is improved.

Here, in the present invention, definitions and technical meanings of terms are as follows unless otherwise specified.

[Airtight Container] An airtight container formed of a material that transmits ultraviolet light and is a dielectric material can be generally manufactured using quartz glass. However, in the present invention, another material can be used as long as it is a material that transmits ultraviolet light and is a dielectric.

The airtight container is not limited to a straight tube as long as it is tubular, and may be curved.

[Internal Electrode] The internal electrode is made of a heat-resistant metal such as nickel, tungsten, molybdenum, or the like.
It is made of a metal such as stainless steel or titanium, and has an internal feeder electrode and a conductive anchor. The internal power supply electrode is disposed on a substantially central axis in the hermetic container and extends in the central axis direction. Each conductive anchor is formed in a ring shape along the inner peripheral surface of the hermetic container, is arranged at substantially equal intervals along the central axis direction of the hermetic container, and is connected to the internal power supply electrode.

The shape of the internal power supply electrode may be rod-like, linear, plate-like or the like, but may be coil-like as in the second aspect of the present invention. In the case of the coil shape, even if it is thermally expanded at the time of lighting, the elongation can be absorbed, and it is possible to prevent the internal power supply electrode from sagging due to the thermal expansion.

[Excimer-producing gas] As the excimer-producing gas, a rare gas such as xenon, krypton or argon, or a mixed gas of a rare gas and a halogen such as fluorine, chlorine, bromine or iodine can be used. The sealing pressure of the excimer generated gas affects the ultraviolet output and the startability. For example, a pressure of 133 to 1013 Pa is appropriate as the sealing pressure of the excimer generation gas.

[External Electrode] The external electrode acts to generate a dielectric barrier discharge between itself and the internal electrode, and ultraviolet rays are emitted from excimers generated by the dielectric barrier discharge. As the structure of the external electrode, a spiral structure, a mesh structure, a printed structure using a conductive paste, or the like can be used.

[Outer tube] The outer tube is made of a material having ultraviolet transmittance, for example, quartz glass. The outer tube is formed to have a size surrounding the airtight container, and in the invention according to claim 8, is formed to have a size in which a flow path space is formed between the outer tube and the outer peripheral surface of the airtight container.

[0052]

FIG. 1 shows a first embodiment of the present invention.
A description will be given based on FIG. FIG. 1 is a front view showing a dielectric barrier discharge lamp, FIG. 2 is a longitudinal side view thereof, and FIG. 3 is a front view showing a part thereof.

1 to 3, reference numeral 1 denotes an airtight container,
2 is an internal electrode, 3 is a lead wire connected to the internal electrode 2,
4 is an external electrode.

The airtight container 1 is made of quartz glass, and has an elongated cylindrical hollow portion 1a having an outer diameter of 11.5 mm and an inner diameter "d" of 9.5 mm, and is formed at both ends of the hollow portion 1a. And a sealing portion 1b. The sealing portion 1b has a pinch seal structure in which a molybdenum foil 5 is embedded.

Xenon is sealed in the hollow part 1a of the hermetic container 1 as an excimer generation gas. This excimer product gas is sealed at a pressure of 133 to 1013 Pa.

The internal electrode 2 is composed of one internal feeder electrode 2a.
And a large number of conductive anchors 2b. The internal feeder electrode 2a is made of nickel, tungsten,
The airtight container 1 is formed by winding a wire having a diameter of 0.1 mm made of a heat-resistant metal such as molybdenum or a metal such as stainless steel or titanium at a pitch of 100% in a coil shape having an outer diameter of 1.2 mm. Are arranged substantially on the central axis and extend in the direction of the central axis, both ends of which are connected to the molybdenum foil 5 and sealed and fixed by the sealing portion 1b.

The conductive anchor 2 b is
a is formed by rolling a wire of the same material as that of a with a diameter of 0.31 mm into a ring shape having an outer diameter "D" of 9.0 mm, and each conductive anchor 2b is connected to an internal power supply electrode by a connecting wire portion 2c. 2a. Each of the conductive anchors 2b is arranged along the central axis direction of the hermetic container 1 by one.
They are arranged at intervals of 5 mm.

The conductive anchor 2b is
It is arranged in such a direction that the inclination angle “θ” with respect to “a” is 80 to 90 °.

The external electrode 4 is provided by winding a metal such as stainless steel having a wire diameter of 0.1 mm in a spiral around the outer periphery of the airtight container 1 at a pitch of 2 mm.

Thus, the dielectric barrier discharge lamp 6 is formed.
Is connected. The high-frequency generation circuit 7 is mainly composed of a high-frequency inverter using a DC power supply as an input power, and its high-frequency output is applied between the internal electrode 2 and the external electrode 4 of the dielectric barrier discharge lamp 6. Therefore, one end of the high-frequency output terminal of the high-frequency generation circuit 7 is connected to the internal electrode 2,
The other end is grounded.

In such a configuration, when a voltage is applied between the internal electrode 2 and the external electrode 4, a dielectric barrier discharge occurs between the electrodes 2 and 4. Thereby, the airtight container 1
The excimer product gas sealed in the hollow portion 1a temporarily combines into a molecular state (excimer state), and when returning from such a molecular state to the ground state of atoms, efficiently emits ultraviolet light with little reabsorption. , The dielectric barrier discharge lamp 6 is turned on. The wavelength range of the emitted ultraviolet light depends on the type of excimer generation gas sealed in the airtight container 1. For example, when a large amount of xenon is sealed, ultraviolet light having a wavelength of 172 nm is emitted.

Here, the internal electrode 2 is an internal feeder electrode 2a.
And the conductive anchor 2b, the conductive anchor 2b comes into contact with the inner peripheral surface of the airtight container 1 when the internal feeder electrode 2a is going to hang down due to its own weight or thermal expansion during lighting. The internal feeder electrode 2a is prevented from drooping greatly. Furthermore, since the internal power supply electrode 2a is formed in a coil shape, the expansion due to thermal expansion can be absorbed by the internal power supply electrode 2a itself, and the internal power supply electrode 2a due to thermal expansion can be absorbed.
Can be further prevented from sagging.

Since the distance between the conductive anchor 2b, which is a part of the internal electrode 2, and the external electrode 4 can be prevented from being large, the distance between the internal electrode 2 and the external electrode 4 may be large. The airtight container 1 has a portion where discharge is likely to occur and a portion where discharge is unlikely to occur.
Of the light distribution in the direction of the central axis can be prevented, and the light distribution can be made uniform. As a result, the uniformity is increased in the portion where the ultraviolet rays are irradiated. In particular,
By defining the outer diameter “d” of the conductive anchor 2b and the inner diameter “D” of the hermetic container 1 so as to satisfy 0.3 <d / D <1.0, the inner electrode 2 and the outer electrode It is possible to prevent a portion where discharge easily occurs and a portion where discharge does not easily occur due to a variation in the distance from the airtight container 4, thereby preventing variations in light distribution in the center axis direction of the airtight container 1 and achieving uniform light distribution. be able to.

Further, since the conductive anchor 2b is uniformly provided, the conductive anchor 2b which is a part of the internal electrode 2 is formed.
b and the inner peripheral surface of the hermetic container 1 which is a dielectric material, and the relationship between the conductive anchor 2b and the external electrode 4 becomes uniform. Discharge is likely to occur, the starting performance is improved, and the starting voltage and the lighting maintenance voltage can be reduced.

Further, since the angle “θ” of the conductive anchor 2 b with respect to the internal power supply electrode 2 a is 80 to 90 °, it is possible to stably generate a creeping discharge on the inner peripheral surface of the hermetic container 1. In addition, since the creeping discharge is stably generated, it is possible to prevent a variation in light distribution in the central axis direction of the airtight container 1 and to achieve a uniform light distribution.

Further, since the excimer generation gas sealed in the hollow portion 1a of the airtight container 1 is sealed at a pressure of 133 to 1013 Pa, the pressure of the sealed excimer generation gas is set to such a high value. The airtight container 1
The molecular weight of the excimer product gas in the inside increases, creeping discharge occurs efficiently, startability is improved, and ultraviolet light emission is performed efficiently.

In this embodiment, the outer diameter “d” of the conductive anchor 2 b and the inner diameter “D” of the hermetic container 1 are set so that 0.3 <d / D <1.0. Although the case where it has been specified is described as an example, in the case of a thick dielectric barrier discharge lamp in which the inner diameter “D” of the hermetic container 1 is 20 mm or more,
The outer diameter “d” of the conductive anchor 2b and the inner diameter “D” of the hermetic container 1 may be set to 5 mm <d <D. Also in this case, it is possible to prevent a portion in which discharge is likely to occur and a portion in which discharge is unlikely to occur due to variation in the distance between the internal electrode 2 and the external electrode 4, thereby preventing variation in light distribution in the center axis direction of the hermetic container 1. Light distribution can be made uniform.

Next, a second embodiment of the present invention will be described with reference to FIG.
It will be described based on. 1 to 3 are denoted by the same reference numerals, and description thereof will be omitted. FIG. 4 is a front view showing a dielectric barrier discharge lamp.

[0069] Dielectric barrier discharge lamp 6 of the present embodiment
a has a double tube structure in which the hermetic container 1 of the dielectric barrier discharge lamp 6 described in the first embodiment is covered with an outer tube 8.

The outer tube 8 is a member made of quartz glass in the form of a straight pipe, and has a size that allows a predetermined gap to be formed between the outer tube 8 and the outer peripheral surface of the airtight container 1. This gap serves as a flow passage space 9 through which an inert gas such as a nitrogen gas or an argon gas described later flows. At both ends of the outer tube 8, a dielectric barrier discharge lamp 6
A pair of plugs 10a and 10b for hermetically sealing are welded. An inlet 11 for introducing nitrogen gas into the channel space 9 is formed in one plug 10a, and an outlet 12 for discharging nitrogen gas from the channel space 9 is formed in the other plug 10b. Is formed. In addition, a nitrogen gas circulation mechanism (not shown) for circulating nitrogen gas at a predetermined flow rate is connected between the inflow port 11 and the discharge port 12. The nitrogen gas circulation flow rate “N (liter / minute)” by the nitrogen gas circulation mechanism is 0 <N ≦ 40, preferably 0 <N ≦ 5.
It has been.

The plugs 10a and 10b are provided with sockets 13a and 13b, respectively. The lead wire 3 of the internal electrode 2 is provided through one socket 13a,
The lead wire 14 of the external electrode 4 is conducted to the other socket 13b. Thus, the dielectric barrier discharge lamp 6a having the double tube structure is formed.

In such a configuration, a voltage is applied between the internal electrode 2 and the external electrode 4 in this embodiment, as in the first embodiment, so that
A dielectric barrier discharge occurs between the four. As a result, the excimer product gas sealed in the hollow portion 1a of the airtight container 1 is temporarily combined with a molecular state (excimer state), and when returning from such a molecular state to the atomic ground state, little reabsorption occurs. Ultraviolet light is efficiently emitted, and the dielectric barrier discharge lamp 6 is turned on. The wavelength range of the emitted ultraviolet light depends on the type of excimer generation gas sealed in the airtight container 1. For example, when a large amount of xenon is sealed, ultraviolet light having a wavelength of 172 nm is emitted.

Here, the dielectric barrier discharge lamp 6a
Is a double tube structure in which the airtight container 1 is covered with the outer tube 8,
Even when the dielectric barrier discharge lamp 6a is used for cleaning and sterilization using ultraviolet rays, dirt from the object to be processed adheres to the outer peripheral surface of the outer tube 8, and the dirt is removed from the airtight container 1 and the airtight container. It does not adhere to the external electrode 4 mounted on the outer peripheral surface of the container 1. Therefore, maintenance such as cleaning of the dielectric barrier discharge lamp 6a can be easily performed. Further, it is possible to prevent metal ions released from the external electrode 4 from adhering to the object.

In the dielectric barrier discharge lamp 6a, the nitrogen gas is caused to flow into the flow passage space 9 by driving the nitrogen gas circulation mechanism at the time of lighting. Thereby, oxygen (oxygen in the atmosphere) can be removed from the inside of the flow passage space 9, and the dielectric barrier discharge lamp 6a can be cooled.

Since ultraviolet rays are easily attenuated by the influence of oxygen, when ultraviolet rays are used for cleaning and sterilization, the presence of oxygen is reduced from the ultraviolet light source to the object to be cleaned and sterilized. It is desirable to do. In the present embodiment, by removing oxygen from the inside of the flow path space 9, it is possible to prevent the ultraviolet light transmitted through the airtight container 1 from being attenuated by oxygen when traveling in the flow path space 9, and to perform cleaning and sterilization. The effect can be enhanced.

The cooling effect of the nitrogen gas flowing in the flow path space 9 causes the dielectric barrier discharge lamp 6a to emit light.
Can be suppressed, and a decrease in the luminous efficiency of ultraviolet rays due to a rise in the temperature of the dielectric barrier discharge lamp 6a can be prevented, and a high luminous efficiency can be maintained. Cooling is
It is effective to perform the operation so that the temperature of the dielectric barrier discharge lamp 6a is 200 ° C. or less.

By setting the nitrogen gas circulation flow rate “N (liter / minute)” by the nitrogen gas circulation mechanism to 0 <N ≦ 40, preferably 0 <N ≦ 5, good cooling can be performed. If the circulating flow rate “N” of the nitrogen gas exceeds 40 liters / minute, the temperature difference due to cooling between the inlet 11 and the outlet 12 increases, and the difference in the amount of ultraviolet light emitted according to the temperature difference increases. Occurs, and the uniformity of light distribution is impaired.

The dielectric barrier discharge lamp 6 of the present embodiment
3A, sockets 13a and 13b are provided at both ends of the outer tube 8, and one of the sockets 13b has a lead wire 1 of the external electrode 4.
When the dielectric barrier discharge lamp 6a is used by attaching it to a cleaning and disinfecting device or the like, the socket 13b to which the external electrode 4 is conducting is brought into contact with a conductive member of the cleaning and disinfecting device because the 4 is conductive. Can be grounded. Therefore, the lead wire 14 of the external electrode 4
This simplifies the wiring structure, and eliminates the necessity of attaching and detaching the lead wire 14 each time the dielectric barrier discharge lamp 6a is attached to and detached from the cleaning / sterilizing apparatus, thereby improving the handleability of the dielectric barrier discharge lamp 6a.

[0079]

According to the dielectric barrier discharge lamp according to the first aspect of the present invention, the internal electrode disposed in the hermetic container has:
An internal power supply electrode disposed substantially on the central axis in the hermetic container and extending in the central axis direction; and a ring-shaped member formed along the inner peripheral surface of the hermetic container and substantially extending along the central axis direction of the hermetic container. Since it has a plurality of conductive anchors arranged at equal intervals and connected to the internal power supply electrode, if the internal power supply electrode tries to hang down due to its own weight or the like, the conductive anchor is placed inside the airtight container. Since the inner power supply electrode is supported in contact with the peripheral surface, the internal power supply electrode can be prevented from drooping greatly. By preventing the drooping, it is possible to prevent the distance between the internal electrode and the external electrode from largely fluctuating, and to cause a large fluctuation between the internal electrode and the external electrode, which is likely to cause a discharge and a portion where discharge easily occurs. It is possible to prevent the light distribution in the central axis direction of the hermetic container from becoming uneven due to the formation of a portion, to make the light distribution uniform, and to increase the degree of uniformity in the portion irradiated with ultraviolet light. . Furthermore, by having a conductive anchor uniformly, since the distance between the conductive anchor that is a part of the internal electrode and the inner peripheral surface of the hermetic container that is a dielectric is reduced,
And, since the relationship between the conductive anchor and the external electrode is uniform, creeping discharge is likely to occur on the inner peripheral surface of the hermetic container, and the startability is improved. It can be reduced.

According to the second aspect of the present invention, in the dielectric barrier discharge lamp of the first aspect, since the internal power supply electrode is formed in a coil shape, the internal power supply electrode thermally expands during lighting. Even if it expands, the internal power supply electrode itself formed in a coil shape can absorb the expansion and prevent the internal power supply electrode from sagging due to thermal expansion. This prevents a variation in the distance between the internal electrode and the external electrode due to the drooping of the internal power supply electrode, and reduces the variation in the light distribution in the center axis direction of the airtight container caused by the variation. The light distribution can be uniformed.

According to a third aspect of the present invention, in the dielectric barrier discharge lamp according to the first or second aspect, the inner diameter of the hermetic container is D mm, and the outer diameter of the conductive anchor is d.
mm, 0.3 <d / D <1.0 prevents a portion where discharge easily occurs and a portion where discharge is unlikely to occur due to variation in the distance between the internal electrode and the external electrode. Thus, it is possible to prevent variations in light distribution in the center axis direction of the hermetic container, and to achieve uniform light distribution.

According to a fourth aspect of the present invention, in the dielectric barrier discharge lamp according to the first or second aspect, the inner diameter of the hermetic container is D mm, and the outer diameter of the conductive anchor is dm.
m, when D> 20 mm, by setting 5 mm <d <D, even in a thick type dielectric barrier discharge lamp in which the inner diameter of the hermetic container is 20 mm or more, the distance between the internal electrode and the external electrode can be reduced. It is possible to prevent a portion where discharge easily occurs and a portion where discharge does not easily occur due to the variation, to thereby prevent the variation of the light distribution in the central axis direction of the airtight container and to achieve a uniform light distribution.

According to a fifth aspect of the present invention, in the dielectric barrier discharge lamp according to any one of the first to fourth aspects, the angle θ of the conductive anchor with respect to the internal feeder electrode is set.
Is set to 80 to 90 °, it is possible to stably generate a creeping discharge on the inner peripheral surface of the hermetic container, and because the creepage discharge stably occurs, the light distribution in the central axis direction of the hermetic container is varied. Can be prevented, and the light distribution can be made uniform.

According to a sixth aspect of the present invention, in the dielectric barrier discharge lamp according to any one of the first to fifth aspects, the excimer generated gas is sealed in an airtight container at a pressure of 133 to 1013 Pa. Therefore, by setting the pressure of the excimer-producing gas to such a high value, the molecular weight of the excimer-producing gas in the hermetic container increases, so that creeping discharge can be efficiently generated, the startability is improved, and ultraviolet light is emitted. Efficiency can be improved.

According to a seventh aspect of the present invention, there is provided the dielectric barrier discharge lamp according to any one of the first to sixth aspects, further comprising a tubular outer tube formed of an ultraviolet-permeable material surrounding the airtight container. Therefore, even when this dielectric barrier discharge lamp is used for cleaning and sterilization, the dirt from the object adheres to the outer peripheral surface of the outer tube because the hermetic container is covered with the outer tube. Since it does not adhere to the external electrodes mounted on the outer peripheral surface of the device, maintenance such as cleaning of the dielectric barrier discharge lamp can be easily performed. Further, it is possible to prevent metal ions released from the external electrode from adhering to the object.

According to the eighth aspect of the present invention, in the dielectric barrier discharge lamp according to the seventh aspect, a flow serving as a flow path of an inert gas is provided between the outer peripheral surface of the airtight container and the inner peripheral surface of the outer tube. Since a passage space is formed, by flowing an inert gas into the passage space, removal of oxygen (oxygen contained in the atmosphere) from the passage space and cooling of the dielectric barrier discharge lamp are performed. Can be performed. By removing oxygen, it is possible to prevent ultraviolet rays transmitted through the airtight container from being attenuated by oxygen when traveling in the flow path space. In addition, the cooling action of the inert gas can prevent a decrease in the luminous efficiency of ultraviolet rays due to a rise in temperature, and maintain a high luminous efficiency.

According to the ninth aspect of the present invention, in the dielectric barrier discharge lamp according to the seventh or eighth aspect, sockets are provided at both ends of the outer tube, and one of the sockets is connected to a lead wire of an external electrode. Therefore, when the dielectric barrier discharge lamp is used by attaching it to a cleaning and disinfecting device, it can be grounded by, for example, contacting the socket to which the external electrode is conducted with a conductive member such as the cleaning and disinfecting device. The wiring structure of the electrodes can be simplified, and the handleability when the dielectric barrier discharge lamp is attached to and detached from the cleaning / sterilizing apparatus can be improved.

[Brief description of the drawings]

FIG. 1 is a front view showing a dielectric barrier discharge lamp according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional side view thereof.

FIG. 3 is a front view showing a part thereof.

FIG. 4 is a front view showing a dielectric barrier discharge lamp according to a second embodiment of the present invention with a part of which is a multi-sided surface.

FIG. 5 is a front view showing an example of a conventional dielectric barrier discharge lamp.

FIG. 6 is a front view showing another example of a conventional dielectric barrier discharge lamp.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Airtight container 2 Inner electrode 2a Inner feeder electrode 2b Conductive anchor 4 Outer electrode 8 Outer tube 9 Flow path space 13a, 13b Socket 14 Lead wire

Claims (9)

[Claims] 1. A tubular hermetic container made of a material that transmits ultraviolet light and is a dielectric; an interior disposed substantially on a central axis in the hermetic container and extending in the central axis direction. A power supply electrode, and a plurality of power supply electrodes formed in a ring shape along the inner peripheral surface of the hermetic container, arranged at substantially equal intervals along a central axis direction of the airtight container, and connected to the internal power supply electrode. An internal electrode having a conductive anchor of;
A dielectric barrier discharge lamp, comprising: an excimer product gas sealed in the hermetic container; and an external electrode mounted on an outer periphery of the hermetic container. 2. The dielectric barrier discharge lamp according to claim 1, wherein the internal power supply electrode is formed in a coil shape. 3. When the inner diameter of the hermetic container is Dmm and the outer diameter of the conductive anchor is dmm, 0.3 <d / D <1.0.
Or the dielectric barrier discharge lamp according to 2. 4. When the inner diameter of the hermetic container is D mm and the outer diameter of the conductive anchor is d mm, and D> 20 mm, 5 mm <d <D.
A dielectric barrier discharge lamp as described. 5. The dielectric barrier discharge lamp according to claim 1, wherein an angle θ of the conductive anchor with respect to the internal power supply electrode is 80 to 90 °. 6. The excimer product gas may be from 133 to 10
6. The dielectric barrier discharge lamp according to claim 1, wherein the dielectric barrier discharge lamp is sealed in the hermetic container at a pressure of 13 Pa. 7. The dielectric barrier discharge lamp according to claim 1, further comprising a tubular outer tube formed of a material that transmits ultraviolet light and surrounds the airtight container. 8. The dielectric according to claim 7, wherein a flow path space serving as a flow path of an inert gas is formed between an outer peripheral surface of the hermetic container and an inner peripheral surface of the outer tube. Body barrier discharge lamp. 9. A socket is provided at both ends of the outer tube,
9. The dielectric barrier discharge lamp according to claim 7, wherein a lead wire of the external electrode is connected to one of the sockets.