JP7343746B2 - UV irradiation device - Google Patents

Description

The present invention relates to an ultraviolet irradiation device, and in particular, by installing an ultraviolet light emitting LED module at one end of a tube made of a material that transmits ultraviolet light such as quartz, and arranging a reflecting plate at the other end, ultraviolet light is emitted from the entire surface of the tube. This invention relates to an ultraviolet irradiation device that enables homogeneous irradiation.

BACKGROUND OF THE INVENTION Conventionally, blacklight fluorescent lamps using discharge lamps such as mercury lamps have been used for sterilizing and disinfecting water, air, and medical instruments, for decoration, for appraising banknotes and antiques, and for curing resin and ink.

On the other hand, in recent years, lighting devices that use LED light sources, which are excellent in power saving, have become popular, and linear light sources that use LEDs as an alternative to conventional ultraviolet lamps and blacklight fluorescent lamps have functions similar to those of fluorescent lamps. Further, an ultraviolet irradiation device using an LED has been proposed.

However, since the ultraviolet light emitted from an LED module has stronger brightness directionality than that of a blacklight fluorescent lamp, for example, when a long tube is used as an ultraviolet irradiation device, the illuminance, brightness, and spread of light directly below it may be biased. There was a problem in that it was not possible to uniformly irradiate the outside with ultraviolet rays from the entire surface and circumference of the tube.

For this reason, for example, as described in Japanese Patent Application Laid-open No. 2016-167589 (Patent Document 1), in order to solve the problem of light directivity due to the above-mentioned LED modules, a plurality of LED modules are installed in the longitudinal direction of the tube. An ultraviolet irradiation device has been developed that irradiates ultraviolet rays to the outside over the entire length of the tube.

However, the ultraviolet irradiation device as described in Patent Document 1 can irradiate the ultraviolet rays emitted from the LED module over the longitudinal direction of the tube, but the There was a problem in that ultraviolet rays could not be irradiated in all directions (360°) of the radiation direction. In addition, the ultraviolet irradiation device as described in Patent Document 1 requires a plurality of LED modules to be arranged in the longitudinal direction of the tube, which consumes more power than an ultraviolet irradiation device with one LED module. A heat sink must be provided as a measure against the heat generated by the plurality of LED modules, which poses a problem in that the weight of the ultraviolet irradiation device itself increases significantly.

In addition, although the ultraviolet rays themselves are not irradiated to the outside, for example, Japanese Patent Laid-Open No. 2006-040850 (Patent Document 2) and Japanese Patent Laid-Open No. 2016-126915 (Patent Document 3) disclose that the LED module directs the light. In order to solve this problem, an LED element is placed at the end of a long glass tube whose inner surface is coated with a fluorescent substance that glows under ultraviolet light, so that its optical axis is not parallel to the central axis of the long glass tube. , a fluorescent LED lamp (visible light irradiation device) has been disclosed that irradiates a fluorescent substance with ultraviolet light emitted from an LED element to cause the entire circumference and entire surface of a long glass tube to emit light and irradiates visible light to the outside. .

However, since the fluorescent LED lamps described in Patent Documents 2 and 3 irradiate ultraviolet light emitted from the LED element onto a fluorescent substance and convert it into visible light, it is difficult to efficiently irradiate the ultraviolet light itself to the outside. There was a problem in that it could not be used as an ultraviolet irradiation lamp for sterilizing water, air, medical instruments, etc., appraising banknotes, and curing resins.

In addition, the fluorescent LED lamps described in Patent Documents 2 and 3 make it possible for the first time to uniformly irradiate visible light from the entire circumference and entire surface of the glass tube by emitting light from a fluorescent substance. There is no technical idea to uniformly irradiate the ultraviolet rays emitted from the LED elements to the outside from all around the glass tube. For this reason, for the fluorescent LED lamps described in Patent Documents 2 and 3, we also considered materials suitable for efficiently and uniformly transmitting the ultraviolet rays irradiated from the LED element to the outside, taking into consideration transmittance etc. There was also the issue that this was not done.

Japanese Patent Application Publication No. 2016-167589 Japanese Patent Application Publication No. 2006-040850 Japanese Patent Application Publication No. 2016-126915

Therefore, the present invention provides an ultraviolet irradiation device that has a simpler structure and saves energy compared to conventional ultraviolet irradiation devices, and that also reduces or eliminates bias in the brightness and spread of the ultraviolet light emitted from the LED module. An object of the present invention is to provide an ultraviolet irradiation device capable of uniformly irradiating ultraviolet rays to the outside from substantially the entire surface and the entire circumference of a tube made of a material that transmits ultraviolet rays, such as quartz.

The present inventors have conducted intensive studies on the arrangement of LED modules that emit ultraviolet rays, the material of the tubes that transmit ultraviolet rays, the surface properties, etc. of tubes such as straight tubes and bent tubes. As a result, by providing a reflector that scatters ultraviolet rays at a position facing the LED module, the ultraviolet rays emitted from the LED module are scattered within the tube made of a material that transmits ultraviolet rays, such as quartz, and the ultraviolet rays are also emitted in the tube. It was discovered that ultraviolet rays could be uniformly irradiated to the outside from substantially the entire surface and the entire circumference of the tube by applying a fine scattering process, and the present invention was completed.

That is, according to the present invention, there is provided a tube made of a material that transmits ultraviolet light and has fine irregularities that scatter ultraviolet light on its inner and/or outer surface, and an ultraviolet light-emitting LED provided at one end of the tube. There is provided an ultraviolet irradiation device comprising a module and a reflector provided at the other end of the tube.

In the ultraviolet irradiation device of the present invention, an ultraviolet light-emitting LED module is arranged at one end of the tube that transmits ultraviolet light, and a reflector is provided at the other end, so that the minimum number of ultraviolet light-emitting LED modules is required. Thus, the ultraviolet rays emitted from the LED module can be scattered into the tube by the reflector. The ultraviolet rays irradiated by the ultraviolet irradiation device of the present invention are used for sterilizing water, air, medical instruments, etc., appraising banknotes, curing resins, etc. Since it must be able to pass through the resin, the wavelength is preferably 200 to 450 nm, more preferably 250 to 410 nm.

Therefore, in the ultraviolet light emitting LED module used in the present invention, the irradiation light (ultraviolet light) includes an optical axis parallel to the central axis in the longitudinal direction of the tube and has a spread angle of 15 degrees or less. It is preferable. In this case, the diffused reflection of the ultraviolet rays emitted from the LED module at a wide angle by the reflector is further amplified, and the ultraviolet rays can be more uniformly scattered within the tube. As described above, an example of an ultraviolet light-emitting LED module in which irradiated light has a predetermined spread angle is a type of LED module in which an LED element is integrated with a TIR lens, a convex lens, or a reflective mirror. Note that the "optical axis" indicates the central direction of the irradiation direction of ultraviolet rays emitted from the LED element, and usually indicates a direction perpendicular to the light emitting surface of the LED element.

Furthermore, in the present invention, it is preferable that the ultraviolet light emitting LED module is provided with a second reflecting plate on the back surface thereof. By providing a second reflector on the back of the LED module, it is possible to further diffuse the ultraviolet rays emitted from the LED module itself and the ultraviolet rays reflected from the reflector placed opposite the LED module into the tube. Therefore, the scattering state of ultraviolet rays can be made more homogeneous.

In this way, the reflector placed at the other end of the tube and the second reflector placed on the back of the UV-emitting LED module diffuse the ultraviolet light emitted from the LED module into the tube. Therefore, it is preferable that the surface has a curved shape that causes the incident irradiation light (ultraviolet light) to be diffusely reflected on the surface.

The ultraviolet irradiation device of the present invention uses a tube made of a material that transmits ultraviolet light and has fine irregularities formed on the inner and/or outer surface to scatter ultraviolet light. Therefore, as described above, the ultraviolet light scattered within the tube is When passing through the tube, the light is scattered even more uniformly by the fine irregularities, and can be emitted uniformly from substantially the entire surface and circumference of the tube.

In addition, the ultraviolet irradiation device of the present invention directly emits the ultraviolet rays emitted from the LED module to the outside without converting or cutting them through a fluorescent material, etc., so it has extremely high energy efficiency and uses only the minimum amount of energy necessary. This ultraviolet light emitting LED module has the excellent effect of emitting high-intensity ultraviolet light from the tube.

Materials that transmit ultraviolet rays include glass materials and resin materials such as acrylic, and any of these materials can be used in the present invention, but generally resin materials have lower ultraviolet transmittance than glass materials, and It is preferable to use a glass material since it tends to deteriorate due to ultraviolet rays. Additionally, some common glass materials do not have good UV transmittance, so the glass tube used in the present invention should be made of quartz, which has extremely high UV transmittance. More preferably, it may be made of either synthetic quartz or fused quartz.

Note that the term "pipe" refers to an elongated cylindrical body with a hollow interior, and this concept also includes straight pipes and bent pipes. Further, the longitudinal section of the "pipe" does not necessarily have to be circular, but may be oval or polygonal. However, in the present invention, from the viewpoint of uniformly emitting the ultraviolet rays emitted from the LED module installed at the end of the tube from substantially the entire surface of the tube, it is preferable to use a tube whose vertical cross section is circular. is preferred. Note that the term "longitudinal cross section" of the tube means a cross section of the tube cut along a plane that is non-parallel to the tube axis extending in the longitudinal direction of the tube and intersects perpendicularly to the tube axis.

In the present invention, the fine irregularities provided on the inner and/or outer surface of the tube in order to scatter ultraviolet rays can also be achieved by, for example, pasting a plastic film on which fine irregularities have been formed on the surface of the tube. . However, if the tube is made of glass material, for example, plastic films generally have lower ultraviolet transmittance than glass materials, and also tend to deteriorate due to ultraviolet light, so sandblasting etc. It is preferable that the surface of the tube itself be processed with fine irregularities.

According to the present invention, an ultraviolet irradiation device is provided at one end of a tube made of a material such as quartz that transmits ultraviolet rays and whose inner and/or outer surfaces are formed with fine irregularities that scatter ultraviolet rays. By configuring the LED module to emit ultraviolet light and a reflector provided at the other end of the tube, unevenness in the brightness and spread of the ultraviolet light emitted from the LED module is alleviated or eliminated. It has the excellent effect of being able to uniformly irradiate the outside with ultraviolet rays from substantially the entire surface and the entire circumference of the tube.

In addition, the ultraviolet irradiation device of the present invention can directly emit ultraviolet rays emitted from the LED module to the outside without converting or cutting them through a fluorescent substance, etc., so energy efficiency is extremely high, and the ultraviolet rays emitted from the LED module can be emitted directly to the outside. High-intensity ultraviolet light can be emitted from the tube in the ultraviolet light emitting LED module.

1 is a cross-sectional view schematically showing a cross section of the ultraviolet irradiation device of Example 1 according to the present invention. FIG. 2 is a cross-sectional view schematically showing a vertical cross section of the ultraviolet irradiation device of Example 1 shown in FIG. 1. FIG. 1 is a partially enlarged cross-sectional view of a cross section of the ultraviolet light emitting LED module of Example 1. FIG. 3 is a photograph showing the state of ultraviolet radiation when the ultraviolet irradiation device of Example 1 emits light. FIG. 2 is a cross-sectional view schematically showing a cross section of an ultraviolet irradiation device of Example 2, in which two ultraviolet irradiation devices according to an embodiment of the present invention are connected in series. 3 is a photograph showing the state of ultraviolet radiation when the ultraviolet irradiation device of Example 2 emits light.

Hereinafter, an ultraviolet irradiation device according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments shown below, and various changes can be made without departing from the technical idea of the present invention.

[Example 1]
FIG. 1 schematically shows a cross section of the ultraviolet irradiation device 1 of Example 1 according to the embodiment of the present invention, and FIG. 2 shows a longitudinal section of the ultraviolet irradiation device 1 shown in FIG. 1. Shown schematically.

As understood with reference to FIGS. 1 and 2, the ultraviolet irradiation device 1 of the first embodiment mainly includes a cylindrical glass tube 2 and an ultraviolet light emitting LED module attached to one end 21 of the glass tube 2. 3, and a reflecting plate 4 attached to the other end 22 of the glass tube 2 facing the LED module 3.

The glass tube 2 used in Example 1 is made of quartz that has extremely high transmittance to ultraviolet rays 5, and may be made of synthetic quartz, fused quartz, or a bonding material thereof. Although not shown, in this embodiment, in addition to glass materials such as quartz, a resin material such as acrylic, or a bonding material between the resin material and the glass material may be used as the ultraviolet transmitting material.

However, quartz materials such as synthetic quartz and fused silica have an extremely higher UV transmittance than resin materials such as acrylic and general glass materials that transmit UV 5, and unlike resin materials, they do not transmit UV 5. Since it does not deteriorate, when quartz is used as the material for the glass tube 2, the ultraviolet rays 5 emitted from the LED module 3 can be emitted directly to the outside with extremely high energy efficiency without being reduced. Therefore, the ultraviolet light emitting LED module 3 to be described later can also emit high-intensity ultraviolet light 5 from the glass tube 2 using the minimum necessary number.

Further, in this embodiment, the glass tube 2 is a straight tube with a circular longitudinal section, but there is no particular limitation on the shape of the glass tube 2. For example, the shape of the longitudinal section may be an ellipse or a polygon. The outer shape in the longitudinal direction may also be curved, such as a bent tube, or the shape and thickness of the longitudinal section may vary along the longitudinal direction.

However, if a straight glass tube 2 with a circular longitudinal section is used as in Example 1, it is easy to manufacture and inexpensive, and the ultraviolet rays emitted from the LED module 3 provided at the end of the glass tube 2 are 5 is advantageous in that it becomes easier to uniformly irradiate substantially the entire surface of the glass tube 2, from the entire circumference.

In Example 1, in order to scatter the ultraviolet rays 5, fine irregularities 20 are formed on the inner and/or outer surface of the glass tube 2 by sandblasting. In Example 1, since the surface of the glass tube 2 itself is processed with fine irregularities, the final transmission of ultraviolet rays 5 is lower than when a plastic film with fine irregularities is attached to the surface of the glass tube 2. without reducing the rate.

In this way, the ultraviolet ray irradiation device 1 of Example 1 uses the glass tube 2 that transmits ultraviolet rays 5 and has fine irregularities 20 formed on the inner and/or outer surfaces that scatter ultraviolet rays 5, so that ultraviolet rays can be emitted. The ultraviolet rays 5 irradiated from the LED 3 are scattered within the glass tube 2, and when passing through the glass tube 2, the scattering is further facilitated by the fine irregularities 20, and the ultraviolet rays 5 are emitted uniformly from almost the entire surface and the entire circumference of the glass tube 2. be done.

In the first embodiment, an ultraviolet light emitting LED module 3 is disposed at one end 21 of a glass tube 2 that transmits ultraviolet rays 5, and a reflection plate 4 is provided at the other end 22. Therefore, in combination with the scattering effect by the glass tube 2 described above, the ultraviolet light 5 emitted from the LED module 3 is scattered by the reflection plate 4 into the glass tube 2 using the minimum necessary number of ultraviolet light emitting LED modules 3. can be done.

FIG. 3 shows a partially enlarged cross section of the ultraviolet light emitting LED module 3 of Example 1.

As shown in FIG. 3, the ultraviolet light emitting LED module 3 used in Example 1 includes an LED main body 30 that emits ultraviolet light 5, and a LED main body 30 that supports the LED main body 30 and is sealed to one end 21 of a glass tube 2. It includes an LED cap 31 that is attached so as to stop the LED cap. The LED main body 30 also includes an LED element 32 that mainly emits ultraviolet rays 5, a circuit section 33 that supplies current to the LED element 32, and a lens section that is formed to cover the LED element 32 and the circuit section 33. It is composed of 34.

In the LED module 3 of Example 1, the lens portion 34 allows the ultraviolet rays 5 to include an optical axis 35 parallel to the central axis 23 (FIG. 1) in the longitudinal direction of the glass tube 2, and to have a spread angle of 15° or less. have. Diffusion of ultraviolet rays 5 within the glass tube 2 is affected by the length and thickness of the glass tube 2, as well as the shape of the reflector 4, but if the spread angle is greater than 15°, the ultraviolet rays 5 will be emitted from the LED module 3. There is a tendency that the reflected ultraviolet rays 5 do not sufficiently reach the reflecting plate 4, making it difficult to efficiently and uniformly scatter the reflected ultraviolet rays 5.

For this reason, in the LED module 3 of Example 1, in order to emit the ultraviolet rays 5 from the LED module 3 with a predetermined spread angle, the lens portion 34 is integrated with a reflecting mirror commonly called a TIR lens. are used. Although not shown, the lens portion 34 may include a bullet-shaped, convex, or concave lens.

Further, in the first embodiment, the ultraviolet light emitting LED module 3 may be provided with a second reflection plate (not shown) on the back surface thereof. When a second reflector is provided on the back side of the LED module 3, the ultraviolet rays 5 emitted from the LED module 3 itself and the ultraviolet rays 5 reflected from the reflector 4 placed opposite the LED module 3 are further absorbed by the glass. Since the ultraviolet rays can be diffused into the tube 2, the scattering state of the ultraviolet rays 5 can be made even more homogeneous.

In the first embodiment, a reflection plate 4 is arranged at the other end 22 of the glass tube 2. As the reflective material used for the reflective plate 4, any material having a high reflectance for ultraviolet rays 5 can be used without particular limitation. Suitable reflective materials include, for example, mirror-finished metals selected from the group consisting of iron, aluminum, titanium, and stainless steel, or alloys containing these metals, or materials made by vapor deposition or plating of these metals. Good too. Further, the reflective plate 4 used in Example 1 includes a reflective cap 40 that supports the reflective plate 4 and is attached to the other end 22 of the glass tube 2 in a sealed manner.

In Example 1, the reflector 4 attached to the other end 22 of the glass tube 2 and the second reflector disposed on the back of the ultraviolet light emitting LED module 3 described above are configured to reflect light emitted from the LED module 3. In order to diffuse the ultraviolet rays 5 into the glass tube 2, it may have a convex curved shape (not shown) that diffusely reflects the incident ultraviolet rays 5 on the surface.

The photograph in FIG. 4 shows the ultraviolet irradiation state when the ultraviolet irradiation device 1 of Example 1 emits light. As shown in FIG. 4, in the ultraviolet irradiation device 1 of Example 1, the bias in the brightness and spread of the ultraviolet light 5 emitted from the ultraviolet light emitting LED module 3 is alleviated or eliminated, and the It was found that ultraviolet rays 5 can be uniformly radiated to the outside from almost the entire surface and all around.

Further, in the ultraviolet irradiation device 1 of Example 1, in order to confirm the effect of the presence or absence of a reflector, a second reflector was not provided on the back surface of the ultraviolet light emitting LED module 3. As a result, in the vicinity of the other end 22 of the glass tube 2, the ultraviolet rays 5 diffused due to the presence of the reflection plate 4 are uniformly scattered and transmitted from the vicinity of the other end 22 of the glass tube 2. On the other hand, in the vicinity of one end 21 of the glass tube 2, the ultraviolet rays 5 emitted from the LED module 3 are emitted with a predetermined spread angle, so compared to the vicinity of the other end 22. It was found that the scattering of ultraviolet rays 5 was not uniform.

For this reason, if a second reflector is provided on the back of the LED module 3, as well as the reflector 4 attached to the other end 22, the ultraviolet rays 5 emitted from the LED module 3 itself and the LED module 3 Since the ultraviolet rays 5 reflected from the reflecting plates 4 disposed at opposing positions can be further diffused into the glass tube 2, it is presumed that the scattering state of the ultraviolet rays 5 can be made even more homogeneous.

[Example 2]
FIG. 5 schematically shows a cross section of an ultraviolet irradiation device 1a of Example 2 according to another embodiment of the present invention.

The ultraviolet irradiation device 1a of Example 2 is obtained by connecting two ultraviolet irradiation devices 1 of Example 1 described above in series. Therefore, the ultraviolet irradiation device 1a of the second embodiment has the same configuration as the ultraviolet ray irradiation device 1 of the first embodiment, except that two reflectors 4 are arranged on the front and back surfaces of the reflective cap 40. Therefore, the same reference numerals as those of the ultraviolet irradiation device 1 of Example 1 are used here, and detailed explanation of the ultraviolet irradiation device 1a of Example 2 is omitted.

In the ultraviolet irradiation device 1a of the second embodiment, an ultraviolet light emitting LED module 3 is attached to each of its both ends (one end 21) via an LED cap 31. In addition, the connecting portions (other ends 22) of the respective ultraviolet irradiation devices 1 constituting the ultraviolet irradiation device 1a of Example 2 are connected in a straight line through reflective caps 40 with reflective plates 4 attached to the front and back surfaces. has been done.

The photograph in FIG. 6 shows the ultraviolet irradiation state when the ultraviolet irradiation device 1a of Example 2 is activated to emit light. As shown in FIG. 6, the ultraviolet ray irradiation device 1a of the second embodiment, like the ultraviolet irradiation device 1 of the second embodiment, has biases such as brightness and spread of the ultraviolet rays 5 emitted from the ultraviolet light emitting LED module 3. It was found that the ultraviolet rays 5 can be uniformly radiated to the outside from substantially the entire surface and the entire circumference of the glass tube 2.

In particular, in the ultraviolet irradiation device 1a of Example 2, since the connecting portion of the two ultraviolet irradiating devices 1 is located on the other end 22 side where the reflection plate 4 is arranged, the connecting portion of the glass tube 2 (the other end 22), the presence of the reflection plate 4 causes the diffused ultraviolet rays 5 to be uniformly scattered and transmitted from the vicinity of the connecting portion of the glass tube 2, so that the presence of the connecting portion of the glass tube 2 is almost unrecognizable. It was found that the particles were scattered over almost the entire surface and all around the area.

For this reason, if a second reflecting plate is provided on the back surface of the LED module 3 in the ultraviolet irradiation device 1 of Example 1 and the second reflecting plate is connected in a straight line, the existence of the connecting part will hardly be recognized, and the ultraviolet emitting LED It has been found that an ultraviolet ray irradiation device having a desired length that can uniformly radiate the ultraviolet rays 5 emitted from the module 3 to the outside from substantially the entire surface and the entire circumference of the glass tube 2 can be obtained.

1, 1a...Ultraviolet irradiation device 2...Glass tube 20...Minute unevenness 21...One end 22...Other end 23...Central axis 3 ...UV light emitting LED module 30...LED body 31...LED cap 32...LED element 33...Circuit section 34...Lens section 35...Light Shaft 4... Reflector plate 40... Reflective cap 5... Ultraviolet rays

Claims (9)

A hollow tube made of a material that transmits ultraviolet rays and has minute irregularities formed on its inner and/or outer surface to scatter ultraviolet rays;
An ultraviolet irradiation device comprising: an ultraviolet light emitting LED module provided at one end of the tube; and a reflection plate provided at the other end of the tube. The ultraviolet irradiation device according to claim 1, wherein the tube is a glass tube. The ultraviolet irradiation device according to claim 2, wherein the glass tube is a quartz tube. The ultraviolet irradiation device according to any one of claims 1 to 3, wherein the fine irregularities are formed by sandblasting. The ultraviolet irradiation device according to any one of claims 1 to 4, wherein the tube has a circular longitudinal section. The ultraviolet irradiation device according to any one of claims 1 to 5, wherein the ultraviolet light emitting LED module is provided with a second reflecting plate on its back surface and/or side surface. 7. The ultraviolet irradiation device according to claim 6, wherein the second reflection plate has a curved shape that diffusely reflects incident irradiation light on the surface. 2. The ultraviolet light emitting LED module according to claim 1, wherein the irradiated light includes an optical axis parallel to the central axis in the longitudinal direction of the tube and has a spread angle of 15 degrees or less. 7. The ultraviolet irradiation device according to any one of 7. The ultraviolet irradiation device according to any one of claims 1 to 8, wherein the reflection plate has a curved shape that diffusely reflects incident irradiation light on the surface.

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