Ultraviolet light sterilization device

Abstract

To provide a sterilization device which has a compact depth dimension and can be easily fitted even in a retrofitted state.SOLUTION: A sterilization device is installed on a notch which is provided on a wall surface forming a ventilation passage. The sterilization device has an ultraviolet radiation unit comprising a plate-shaped light guide member which is arranged along an air movement direction of air flowing in an air passage. The light guide member receives light emitted from a plurality of ultraviolet LEDs which are arranged and face an incident surface provided at a side surface of the light guide member. A surface on the air passage side of the light guide member and a side face opposite to the incident surface serve as an emission surface of the ultraviolet entered the light guide member. By widening an area of the emission surface of the ultraviolet light, sterilization of bacteria and the like floating in the air is executed by the emitted ultraviolet. Since the light guide member is used, resistance to an air flow can be reduced in fitting.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a sterilization device that uses ultraviolet light to kill or eliminate microorganisms such as viruses, Escherichia coli, Staphylococcus aureus, and mold that are attached to surfaces or suspended in air. [Background technology]

[0002] Air purifiers are known that are activated by a light source to cause a photocatalytic reaction, and exert deodorizing, deodorizing, sterilizing, and disinfecting effects to remove bad odors, purify the air, disinfect, and kill bacteria. Conventionally, light sources that generate ultraviolet rays, such as sunlight, mercury lamps, and black lights, have been used as light sources. For example, Patent Document 1 discloses a deodorizing and disinfecting device that applies a high voltage (1 to 15 KV) between electrodes arranged opposite each other to generate a corona discharge between the electrodes, generating corona discharge light, and irradiates a photocatalyst with the corona discharge light using a reflector. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-293070 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the deodorizing and sterilizing device described in Patent Document 1 uses corona discharge light, so the device becomes large. In addition, the electrodes that generate corona discharge light are installed in an air passage through which air passes, facing each other on the upstream side and downstream side of the air passage. Therefore, each electrode protrudes so as to block the air passing through the air passage, and is arranged perpendicular to the passage. This hinders the flow of air and causes the flow rate to slow down. In addition, it is not easy to install in a limited space. As a result, it is difficult to install in a limited, narrow space, such as an interior air conditioner of an automobile. In addition, it is also difficult to install it after the fact.

[0005] The present invention has been made in consideration of the above-mentioned points, and has as its main object to provide a sterilization device that can be easily installed in an air passage. Another object of the present invention is to provide a sterilization apparatus that has a large area of ​​an ultraviolet light emission surface and irradiates ultraviolet light over a wide area within an air passage. [Means for solving the problem]

[0006] In order to achieve the above object, one aspect of the present invention provides a sterilization device using ultraviolet light as described below in [1] to [4].

[0007] [1] An air vent having an inlet for introducing air and an outlet for discharging air. In front of the road An air passage between the inlet and the outlet Attachable sterilization unit A sterilization device comprising: The sterilization unit includes a plate-shaped light guide member arranged along the direction of air flow in the air passage. and a mounting portion for fixing the air passage. The ultraviolet light irradiation unit includes: The ultraviolet light irradiation unit includes a plurality of ultraviolet LEDs arranged to face one end surface of the light guide member, an LED mounting substrate on which the plurality of ultraviolet LEDs are mounted in a row, and a reflecting member covering the surface of the light guide member opposite to the air passage side. and a fixing frame for fixing the light guide member. Has the light guiding member has a first surface located on the side opposite to the air passage, a second surface located on the air passage side, a first end face facing the LED mounting board, and a second end face located on the opposite side to the first end face; the reflecting member is a metal sheet having a reflecting surface in close contact with the first surface and covering the entire first surface; the fixing frame has an opening that covers a corner portion of the second end surface of the light guiding member and exposes a central portion of the second end surface, and is made of a metal material provided along an edge of the second surface, the fixing frame and the reflecting member sandwich the light guiding member, The second surface and The second end surface is an emission surface from which light emitted from the ultraviolet LED and guided through the light-guiding member is emitted, The mounting portion is The exit surface is exposed within the air passage. The air passage is formed so as to be fixed to a rear surface of a duct that forms the air passage, The LED mounting board is located downstream of the air passage, Of the light emitted from the ultraviolet LED, incident on the light-guiding member, and emitted from the emission surface, the ultraviolet light that exits through the second end surface exits toward the upstream side, and the ultraviolet light that exits through the second surface exits in an oblique direction from the downstream side to the upstream side of the air passage. Sterilization device. [2] The sterilization unit includes a photocatalytic material that is excited by light having an emission wavelength of the ultraviolet LED; The air passage includes: The second surface The sterilization device according to the above [1], further comprising a photocatalyst body containing the photocatalyst material disposed opposite the photocatalyst body. [3] The plurality of LEDs include an LED that emits ultraviolet light in the UV-C range. The sterilization device described in [1] or [2] above. [4] The first surface The sterilization device according to any one of the above [1] to [3], wherein a plurality of scattering regions having an uneven shape are provided at the boundary between the reflecting member and the light source. [5] A visible light emitting unit is provided on the opposite side of the LED mounting substrate from the light guide member side, The visible light emitting unit includes a visible LED light source capable of emitting a single color or a plurality of colors, and a visible LED lighting control unit that controls lighting of the visible LED light source, The visible LED lighting control unit controls the visible LED in synchronization with lighting of the ultraviolet LED. light source The sterilization device according to any one of [1] to [4] above, which starts lighting up the lamp. [6] The second surface and the second end face protrude into the air passage from the duct, and the attachment portion is located outside the air passage. Sterilization device. Effect of the Invention

[0008] From the above [1] [6] According to the invention described in the above, an ultraviolet light irradiation unit is provided with a plate-shaped light-guiding member arranged along the direction of air movement through the air passage, so that a configuration can be achieved that is less likely to generate resistance to the air flow, thereby providing a sterilization device that can be easily installed in the air passage.

[0009] In addition, the ultraviolet light irradiation unit is configured so that light from an ultraviolet LED provided on the end face of a plate-shaped light-guiding member is emitted from the surface on the air passage side and the other end face of the light-guiding member.This reduces attenuation of ultraviolet light irradiated from the ultraviolet LED, enables the air passage to be irradiated from a wide area, and can also be irradiated in the direction of air flow along the air passage, so a sterilization device can be provided that can irradiate ultraviolet light over a wide area within the air passage. In addition, according to the invention described in [2] above, a photocatalyst is provided at a position opposite to the emission surface, which promotes the decomposition of organic matter through photolysis, and enhances the deodorizing effect of the photocatalyst action in addition to the sterilizing effect of irradiating airborne substances with ultraviolet light. But Cut. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic overall view illustrating a vehicle air conditioner equipped with a sterilization device according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic perspective view showing a duct tip and an outlet (discharge port) of an air conditioner. [Diagram 3] FIG. 3 is a schematic cross-sectional view for explaining the sterilization unit. [Figure 4] FIG. 4 is a schematic perspective view showing a main part of the ultraviolet light irradiation unit as viewed from the second end face side. [Diagram 5] FIG. 5 is a schematic perspective view illustrating a light guide member used in the ultraviolet light irradiation unit of the modified example. [Figure 6] FIG. 6 is a cross-sectional view illustrating a main part of the ultraviolet light irradiation unit. [Figure 7] FIG. 7 is a schematic cross-sectional view of a main part for explaining the sterilization unit according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sterilization apparatus according to a preferred embodiment of the present invention will now be described with reference to the drawings.

[0012] First Embodiment A sterilization apparatus 1 according to a first embodiment will be described with reference to Figs. 1 to 6. Fig. 1 is a schematic overall view of an air conditioner 100 for a vehicle to which a sterilization apparatus 1 according to an embodiment of the present invention is attached. As shown by hatching in Fig. 1, the air conditioner 100 for a vehicle introduces air from, for example, the interior or exterior of a passenger vehicle (vehicle) and discharges the air from an outlet into the passenger vehicle. The temperature of the air in the vehicle is adjusted by adjusting the temperature of the air inside the air conditioner 100. In the example of Fig. 1, a second air conditioner is provided. The air conditioner 101 in front of the driver's seat has a plurality of outlets, each of which discharges air toward the area near the front seats 110, the windshield, and the rear seats 111. The air conditioner 102 in the rear of the vehicle also has a plurality of outlets, each of which discharges air with the temperature adjusted toward the upper center of the passenger compartment and the rear seats.

[0013] The air conditioner 101 in front of the driver's seat is equipped with an outside air intake 3a provided near the bottom of the windshield at the front of the vehicle to take in outside air, and an inside air intake 3b provided inside the vehicle to take in air, and discharges temperature-adjusted outside air or inside air from an outlet 105a into the vehicle through a duct (air passage) 103 that passes under the front seats 110. The air conditioner 101 is equipped with a temperature adjustment device (evaporator, compressor, etc.) (not shown), a fan that circulates air, and a damper that switches between inside air and outside air. The flow rate and flow speed of the air flowing inside the duct 103 is controlled by a fan that blows air toward the outlet. Like the air conditioner 101 in front of the driver's seat, the air conditioner 102 at the rear of the vehicle is equipped with a temperature control device, a fan, a damper, and an air intake (not shown), and is configured to allow air to flow out from an outlet 105b provided between the front seat 110 and the rear seat 111 through a duct 104 provided along the ceiling.

[0014] (Sterilization unit) Fig. 2 is a schematic perspective view showing the tip portion and air outlet 105a of duct 103 provided under the front seat of front air conditioner 101. Fig. 3 is a schematic cross-sectional view for explaining sterilization unit 10, taken along the extension direction of the duct (air flow direction). Inside each of ducts 103 and 104, sterilization units 10 are provided upstream of air outlets 105a and 105b, i.e., on the air intake side. The sterilization units provided in front air conditioner 101 and rear air conditioner 102 are the same sterilization unit 10. The sterilization unit 10 may be provided near another air outlet.

[0015] In the following description, the sterilization unit provided in the front air conditioner 101 will be described in detail. The sterilization unit 10 is attached to the duct side wall 103a near the air outlet 105a as shown in FIG. 2. An air passage 2 through which air flows is formed inside the duct. The sterilization unit 10 is fixed to a part of the duct side wall 103a that is cut away. The sterilization unit 10 is fixed so as to be disposed along the air passage 2 so that the air passage side is in contact with the air flowing in the air passage as shown in FIG. 2. The sterilization unit 10 is equipped with an ultraviolet light irradiation unit 20. The air flowing in the duct 104 is blown from the intake side to the exhaust side by a fan (not shown). The direction indicated by the arrow in FIG. 3 is the movement direction F of the air flowing from the upstream side (intake side) to the downstream side (exhaust side). When taking the air flowing through the air passage 2 where the sterilization unit is installed as a reference, the outside air intake 3a and the inside air intake 3b correspond to the inlets of the sterilization device 1 in the present invention, and the outlet 105a corresponds to the exhaust outlet 4.

[0016] (Ultraviolet light irradiation unit) The ultraviolet light irradiation unit 20 includes a plate-shaped light guide member 21 arranged along the movement direction F of the air flowing through the duct 104 as shown in FIG. 3. The ultraviolet light irradiation unit 20 is fitted into an opening provided by cutting out a part of the duct side wall 103a, and is fixed so that air does not leak from the duct 104 by fixing the mounting part 27 to the duct side wall 103a using a screw 28. In order to reduce air leakage, it is preferable to fix the ultraviolet light irradiation unit 20 and the duct 103a via a rubber packing or an elastomer member having elasticity. In addition, a part of the duct side wall 103a is formed thick in order to fix the ultraviolet light irradiation unit 20 and the duct 103a using the screw 28. Fixation is not limited to using a screw, and the ultraviolet light irradiation unit 20 may be fixed by adhering the periphery of the ultraviolet light irradiation unit 20 to the opening part cut out of the duct side wall 103a with an adhesive.

[0017] The light guide member 21 is formed in a plate shape using a material that has the property of transmitting ultraviolet light, particularly ultraviolet light in a wavelength range that has a sterilizing effect and is also called germicidal rays. In this embodiment, synthetic quartz glass is used. Synthetic quartz glass is more expensive than soda glass, but has excellent ultraviolet light transmission properties and is therefore suitable as a light guide member. Soda glass, which is widely used for window glass, has a thickness of, for example, 4 mm and a germicidal ray transmittance of approximately 0%, while crystalline quartz has a transmittance of 99% or more at a thickness of 1 mm. Synthetic quartz glass is also transparent to light in the ultraviolet range of 180 nm.

[0018] As an alternative material, resin materials can be used. However, for example, ABS resin changes and hardens due to cross-linking reaction of polybutadiene when exposed to ultraviolet light. It is thought that the molecules in the non-crystalline region of PP are easily cut, and grooves appear when exposed to ultraviolet light. PC turns yellow. Silicone resin, acrylic resin, and silicone modified epoxy resin show high transmittance of 80% or more for light with wavelengths longer than 300 nm, but their transmittance for ultraviolet light with shorter wavelengths in the UV-B and UC-C regions is low. Therefore, an appropriate material should be selected depending on the type of ultraviolet LED used. If quartz glass is used, it can transmit ultraviolet light in the UV-A, UV-B, and UV-C regions at least. For example, the Violamo ultraviolet-transmitting disposable cells UVC series sold by AS ONE Corporation are transparent to light in the ultraviolet range to the visible range (220 to 800 nm) (https: / / axel.as-1.co.jp / asone / g / NCGK066351 / ?q=%E7%B4%AB%E5%A4%96%E7%B7%9A%E9%80%8F%E9%81%8E), so the same material can be used as the light-guiding member 21.

[0019] UV-A is ultraviolet light with a wavelength of 315 to 400 nm, as classified by wavelength by the CIE (International Commission on Illumination). UV-B is ultraviolet light with a wavelength of 280 to 315 nm. UC-C is ultraviolet light with a wavelength of 100 to 280 nm. In the narrow sense, germicidal rays refer to ultraviolet light with a strong germicidal effect at a wavelength of 253.7 nm, but in the description of this application, germicidal rays are defined as ultraviolet light in a wavelength range that shows germicidal effects even at wavelengths other than 253.7 nm. For example, it has been reported that deep ultraviolet LEDs with a wavelength of 275 nm have germicidal and inactivating effects on Escherichia coli, influenza viruses, noroviruses, etc., and inactivation by deep ultraviolet LEDs with a wavelength of 265 nm has also been reported. The following description will assume that ultraviolet light in the UV-C range, which is the wavelength range reported in such reports, is also included in germicidal rays.

[0020] The light guide member 21 is a plate-shaped rectangular parallelepiped arranged so that the surface with the largest rectangular area is located when viewed from the air passage 2 side. As shown in FIG. 3, a plurality of ultraviolet LEDs 23 are arranged so as to face one of the four side surfaces of the rectangular parallelepiped. This one side surface is the first end surface 21a, which is the incident surface into which the light emitted from the ultraviolet LEDs 23 is incident. The end surface opposite the first end surface 21a is the second end surface 21b. FIG. 4 is a schematic perspective view showing the main parts of the ultraviolet light irradiation unit 20 as viewed from the second end surface side. The second end surface 21b is the side surface from which part of the light emitted from the ultraviolet LEDs 23 that is incident from the first end surface 21a exits. can be , which functions as an exit surface.

[0021] The surface of the light guide member 21 opposite to the air passage 2, i.e., the surface located on the upper side of the paper in Fig. 3, is the first surface 21c. A reflecting member 25 is provided above the first surface 21c so as to cover the entire first surface 21c and the ultraviolet LEDs 23. The surface opposite to the first surface 21c, i.e., the surface located on the air passage 2 side, is the second surface 21d. The second surface 21d also functions as an exit surface from which part of the light emitted from the ultraviolet LEDs 23 that entered from the first end surface 21a exits.

[0022] (ultraviolet light source) A plurality of ultraviolet LEDs 23 mounted on an LED mounting substrate 24 are used as the ultraviolet light source. The ultraviolet LEDs 23 include LEDs in a surface-mounted package in which at least an LED (light-emitting diode) element that emits sterilizing radiation is installed inside a frame made of ceramic or metal, and electrodes for joining to a solder land formed on a printed circuit board are provided on the outside. The plurality of ultraviolet LEDs are mounted on one surface of the LED mounting substrate 24 so as to be aligned in a row along the first end surface 21a of the light guide member 21. In order to reduce the size and weight of the ultraviolet light irradiation unit, it is preferable to use a light guide member 21 in which the plurality of ultraviolet LEDs 23 are aligned in a row and the size of the first end surface 21a, which serves as the entrance surface, is thin in accordance with the size of the ultraviolet LEDs 23 aligned in a row. The plurality of ultraviolet LEDs 23 may include LEDs that emit ultraviolet light of different wavelengths. In this embodiment, the plurality of ultraviolet LEDs 23 are aligned in a row and used as the plurality of ultraviolet LEDs 23.

[0023] (LED mounting board) The LED mounting substrate 24 uses a metal base substrate made by bonding aluminum or copper plate with a highly thermally conductive resin. By using a metal base substrate, it is possible to achieve higher heat dissipation than when a rigid substrate is used, and it is possible to improve the dissipation of heat generated from the ultraviolet LEDs 23. The LED mounting substrate 24 is provided with wiring and connectors that connect the ultraviolet LEDs 23, and the lighting state of the ultraviolet LEDs 23 is controlled according to a signal from an ultraviolet LED lighting control unit (not shown). The LED mounting substrate 24 is fixed to the reflecting member 25 together with the light guide member 21. This allows the ultraviolet LEDs 23 to be positioned accurately relative to the incident surface (first end surface 21a).

[0024] (Reflective material) The reflecting member 25 is formed by folding an aluminum metal sheet. As shown in FIG. 3, a flat plate portion 25a that covers the entire surface of the first surface 21c of the light guide member 21 and extends from the edge of the first end surface 21a side of the first surface 21c, and a light shielding portion 25b that is bent perpendicularly from the flat plate portion 25a and is located on the back surface of the LED mounting substrate 24 are integrally formed. The surface of the flat plate portion 25a on the light guide member 21 side is a reflective surface provided with an aluminum layer having a polished surface or a smooth surface with high reflectivity, and is arranged in close contact with the first surface 21c so that the light from the ultraviolet LEDs 23 that enters the inside of the light guide member 21 is reflected and returned to the first surface 21c when it is emitted to the outside from the first surface 21c. Aluminum has a high reflectivity for light of ultraviolet wavelengths and is lightweight, so it is particularly suitable for use in vehicle air conditioners. The light shielding portion 25b has an area larger than the first end surface 21a of the light guide member 21 and is located on the back surface of the LED mounting substrate 24. The light shielding portion 25b also functions as a partition for separating light emitted by a visible LED light source of a visible light emitting unit (to be described later) from light emitted by the ultraviolet LEDs 23, as shown in FIG.

[0025] Furthermore, a protrusion 25c is provided at the end of flat plate portion 25a opposite light-shielding portion 25b, which, together with a region extending from back cover 27a as shown in Figure 3, constitutes mounting portion 27. Mounting portion 27 is fixed to the outer wall portion of duct 104 with screws. Back cover 27a is formed in a roughly box shape that covers the back surface of reflective member 25 and the back surface of printed circuit board 33 of visible light emitting unit 30, which will be described later, and protects sterilization unit 10.

[0026] (Fixed frame) As shown in FIG. 3, the second surface 21 of the light guide member 21 is provided with a fixing frame 29 along the edge of the second surface 21, and the light guide member 21 is sandwiched between the fixing frame 29 and the reflecting member 25. The fixing frame 29 is also made of aluminum metal, which is less likely to deteriorate due to ultraviolet rays generated from the ultraviolet LEDs 23 and has a high reflectance, making it suitable as a material for holding the light guide member 21. A part of the fixing frame 29 is also provided on the second end face 21b side. The fixing frame 29 provided on the second end face 21b side has an opening 29a that covers the corner of the light guide member 21 and exposes the center part of the second end face 21b, as shown in FIG. 4. Since the multiple ultraviolet LEDs 23 are arranged to face the first end face 21a, it is preferable to configure the optical axis of the ultraviolet LEDs 23 to pass through the first end face 21a, the second end face 21b, and the opening 29a. As a result, a part of the light emitted from the ultraviolet LEDs 23 can pass through the opening 29a and irradiate the inside of the air passage 2 toward the upstream side.

[0027] In the case where the inside of the air passage 2 is irradiated with ultraviolet light through the opening 29a, as shown in FIG. 3, the opening 29a is positioned on the upstream side of the air flowing through the air passage 2, and the ultraviolet LEDs 23 are positioned on the downstream side. Conversely, if the opening 29a is positioned on the downstream side, the light from the ultraviolet LEDs 23 installed on the upstream side is irradiated to the downstream side through the opening 29a. If ultraviolet light is irradiated to the downstream side, it is likely to leak into the vehicle from the outlet 105a. Therefore, it is preferable to install the ultraviolet LEDs 23 so that the irradiation light passing through each optical axis of the ultraviolet LEDs 23 is directed from the downstream side to the upstream side, so that the ultraviolet light does not leak into the vehicle.

[0028] Next, a case where the ultraviolet LED 23 is turned on will be described.

[0029] When the ultraviolet LED 23 is an LED that emits light of a sterilizing wavelength, it may be possible to inactivate or kill E. coli, norovirus, and the like by the ultraviolet light of the sterilizing light. Inactivation of coronaviruses has also been reported. It is said that the sterilizing effect of ultraviolet light is achieved by inactivating bacteria and viruses by directly damaging RNA. The ultraviolet LED 23 is controlled in its on state by an ultraviolet LED lighting control unit (not shown), and a drive signal is supplied to the ultraviolet LED 23 via the LED mounting board 24. When the ultraviolet LED 23 is turned on, ultraviolet light is irradiated toward the first end face (incident surface) 21a of the light guide member 21. Of the ultraviolet light introduced into the light guide member 21 from the first end face (incident surface) 21a, a part of the light travels straight through the light guide member 21 toward the second end face 21b, and another part of the light travels toward the second end face 21b while repeatedly reflecting inside the light guide member 21.

[0030] Light that enters the light-guiding member 21 from the first end face (incident surface) 21a and travels straight toward the second end face 21b travels straight and exits from the second end face 21b (exiting side surface). The exiting light UV1 that is emitted from the second end face 21b toward the inside of the air passage 2 is irradiated toward the upstream side as shown by the arrow in FIG. 3. Light that travels straight is less subject to reflection and loss at interfaces. Furthermore, the light emitted from the ultraviolet LED has the highest illuminance on or near the optical axis. Therefore, it is possible to irradiate the air with ultraviolet light of high intensity.

[0031] Also, a part of the light that is repeatedly reflected in the light guide member 21 and travels toward the second end surface 21b is reflected by the first surface 21c and travels toward the second surface (exit surface) 21d, and irradiates the inside of the air passage 2 from the second surface (exit surface) 21d. Therefore, it is possible to irradiate from a wide area so as to cross the air flowing inside the air passage 2. Of the light that is guided inside the light guide member 21 and reaches the second surface 21d, if the light reaches at an angle less than the critical angle, it is internally reflected and is not emitted to the outside. Only the light that reaches at an angle exceeding the critical angle is emitted to the outside. Therefore, the light UV2 that is emitted to the outside of the light guide member 21 is mainly light that is emitted at an angle slightly exceeding the critical angle, that is, light that is obliquely emitted in the direction opposite to the incident surface at an angle of several degrees with respect to the second surface 21d. Therefore, the emitted light UV2 is emitted obliquely from the downstream side to the upstream side of the air flowing in the air passage as shown by the dashed arrow in Fig. 3, and ultraviolet light is not emitted from the upstream side to the downstream side. This makes it possible to prevent ultraviolet light from leaking into the room from the downstream air outlet 105a.

[0032] The amount of ultraviolet light required to kill microorganisms such as bacteria varies depending on the wavelength, with UV-B being more effective than UV-A and requiring a smaller amount of irradiation. Furthermore, UV-C is more effective than UV-B. Therefore, by using the ultraviolet LED 23 in the UV-C wavelength range, it is possible to kill them in a shorter time. In this embodiment, a wide range can be irradiated, so that microorganisms and viruses floating in the air in the air passage 2 can be efficiently killed. The areas of the second surface 21d and the second end surface 21b, which are the emission surfaces, can be adjusted according to the amount of ultraviolet light irradiation and irradiation time of the ultraviolet LED used.

[0033] Next, a description will be given of the visible light emitting unit 30 provided on the back side of the LED mounting board 24 shown in Fig. 3. In this embodiment, the sterilization unit 10 also includes the visible light emitting unit 30.

[0034] (Visible light emitting unit) The visible light emitting unit 30 is a part that has a function of indicating the lighting state of the ultraviolet LEDs 23 and a function of illuminating the sterilization device 1 to enhance the design. The visible light emitting unit 30 includes a visible LED light source 31 installed on one surface side of a printed circuit board 33, and an electronic component 32 for lighting control installed on the other surface side. As shown in FIG. 3, the printed circuit board 33 is fixed to the back surface of the flat plate portion 25a of the reflecting member, and the visible LED light source 31 is arranged so as to irradiate visible light in a direction crossing the air passage 2. The area on the back surface side of the LED mounting board 24 on which the visible LED light source 31 is installed is optically partitioned by the light shielding portion 25b of the reflecting member on the light guide member 21 side, and the opposite side to the light guide member side and the air passage 2 side facing the visible LED light source 31 are partitioned by a storage frame body 34 having a through hole 35. By arranging in this manner, the visible light emitting unit 30 can be provided downstream of the air passage, i.e., near the air outlet 105a, and the visible LED light source 31 cannot be directly seen through the air outlet 105a. Therefore, it can function as indirect lighting for illuminating the interior of the vehicle, improving the lighting quality.

[0035] The storage frame body 34 is integrally formed by bending the reflecting member 25. The storage frame body 34 and the reflecting member 25 may be formed separately and assembled into one body. The through holes 35 are provided to illuminate the visible light irradiated from the visible LED light source 31 as leaking light from multiple locations toward the inside of the duct 104. A plurality of through holes 35 are provided at positions different from the optical axis of the visible LED light source 31. By providing a plurality of through holes at positions away from the optical axis, light with high brightness directly above the optical axis at multiple locations from the storage frame body 34 is reflected by the storage frame body 34 and then emitted from the through holes 34, so that the brightness of the visible light emitted from the through holes 35 can be homogenized, and the homogenized light can be emitted as leaking light. As a result, when the air outlet 105a is observed, the inside of the duct can be widely illuminated, and the design can be improved by improving the performance of illumination by visible light. The number of through holes 35 is not limited to four as shown in the figure, but may be greater than four, and the storage frame 34 may be made of a mesh material.

[0036] The visible LED light source 31 may be an LED that emits a single color, but it is preferable to use a multi-emitting surface-mount type LED that has three types of LED elements, R, G, and B, in one package so that they can emit multiple colors and can be turned on individually. If the light is switched between red (R), green (G), and blue (B) or mixed colors, it will be possible to illuminate the air outlet with various colors, further enhancing the presentation.

[0037] The visible LED lighting control unit 32 controls the turning on and off of the visible LED light source 31. The turning on and off of the ultraviolet LEDs 23 of the ultraviolet light irradiation unit 20 is controlled by an ultraviolet LED lighting control unit (not shown). The visible LED lighting control unit 32 may be a circuit including the ultraviolet LED lighting control unit as a functional block.

[0038] Since ultraviolet light is not visible light, even when the ultraviolet LED 23 is turned on, the lighting state cannot be confirmed visually. In this embodiment, when the ultraviolet LED 23 is turned on, the visible LED lighting control unit 32 is controlled so that the visible LED light source 31 is turned on at the same time. Specifically, a signal synchronized with the ON / OFF signal output from the ultraviolet LED lighting control unit to the ultraviolet LED 23 is input to the visible LED lighting control unit 32, and the ON / OFF of the ultraviolet LED 23 and the ON / OFF of the visible LED light source 31 are completely synchronized. This makes it possible to inform the user that the ultraviolet LED 23 is turned on by the visible LED light source 31 being turned on. In addition, a sensor element that receives ultraviolet light irradiated from the ultraviolet LED 23 may be provided, and based on the output signal from the sensor element, it may be determined whether the ultraviolet LED 23 is turned on / off normally. If it is determined to be normal, the visible LED lighting control unit 32 may turn on the visible LED light source 31 in normal mode, and if it is determined to be abnormal, the visible LED lighting control unit 32 may keep the visible LED 31 off or turn it on in abnormal mode according to the malfunction, for example, by flashing red light to indicate an alarm state, similar to an alarm lamp.

[0039] In this embodiment, the sterilization unit 10 is provided only on one side wall 103a of the duct 104, but the sterilization unit 10 may also be provided on the other side walls. By irradiating the air flowing through the air passage 2 with ultraviolet light from multiple directions at the same time, the amount of ultraviolet light irradiated on suspended matter such as bacteria in the air can be increased, and the sterilization effect can be improved. In addition, the light is emitted from both the second end face (exiting side face) 21b and the second surface 21d as the exit surface through the light guide member 21, but the fixed frame 29 may be configured to have a reflective inner surface without the opening 29a, and the ultraviolet light emitted from the second end face (exiting side face) 21b may be returned to the inside of the light guide member 21, and only the second surface 21d may be used as the exit surface.

[0040] The sterilization device 1 of this embodiment has an ultraviolet light irradiation unit using the light guide member as described above, so that it can be configured to generate little resistance to the air flow. In addition, since a thin and compact ultraviolet light irradiation unit can be obtained, it is possible to provide a sterilization device that can be easily installed and can be attached to the wall surface that constitutes the air passage even after installation.

[0041] In addition, the ultraviolet light irradiation unit is configured to emit light from an ultraviolet LED provided on the end face of a plate-shaped light-guiding member from the surface of the light-guiding member on the air passage side, or from the surface on the air passage side and another end face.This reduces attenuation of ultraviolet light irradiated from the ultraviolet LED and allows the air passage to be irradiated from a wide area, thereby providing a sterilization device that can irradiate ultraviolet light over a wide area within the air passage.

[0042] (Modification) Next, a modified example will be described. In the above embodiment, a plate-shaped synthetic quartz glass was used as the light guide member 21. Although synthetic quartz glass exhibits high transmittance even for ultraviolet light, it is a hard inorganic material, and it is difficult to mold it into any shape using a manufacturing device such as an injection molding device, as with transparent resin materials. Therefore, in this modified example, fine irregularities are formed by etching the surface of the light guide member 21. FIG. 5 is a schematic perspective view illustrating a light guide member used in the ultraviolet light irradiation unit of the modified example, and FIG. 6 is a cross-sectional view illustrating the main part of the ultraviolet light irradiation unit. In FIGS. 5 and 6, the fine irregularities are shown with exaggerated dimensions.

[0043] As shown in FIG. 5 and FIG. 6, the scattering region 26 is formed on the surface of the first surface 21c located on the opposite side of the exit surface. The scattering region 26 is located at a plurality of scattered locations on the boundary between the surface of the first surface 21c facing the reflecting member 25. To create the scattering region 26, a mask is provided on the surface of the first surface 21c to cover the surface other than the portion where the scattering region 26 is provided, and the first surface 21c not covered by the mask is etched to create a minute uneven shape. The etching may be wet etching using a predetermined chemical or dry etching using a predetermined gas. A method of forming unevenness by applying a physical force such as sandblasting is not preferred because there is a risk of damaging the synthetic quartz glass. The size of the uneven shape is not limited as long as it causes scattered reflection.

[0044] By providing the scattering region 26 on the first surface 21c located opposite to the exit surface, the direction of the emitted light UV3 from the second surface 21d can be made to be other than the oblique light mainly emitted toward the upstream side as shown in FIG. 6. That is, the irradiation area by the ultraviolet light can be expanded. Since the amount of ultraviolet light emitted from the ultraviolet LED 23 is the same, expanding the irradiation area reduces the amount of ultraviolet light irradiation per unit area. Therefore, when the amount of ultraviolet light emitted from the ultraviolet LED 23 is small, it is preferable not to provide the scattering region 26. When the flow speed of the air flowing through the duct is slow or the volume of the air passage is small, it is better to provide the scattering region 26 so that more air can be irradiated.

[0045] Second Embodiment Next, a modified example will be described. Fig. 7 is a schematic cross-sectional view of a main part for explaining a sterilization unit in a second embodiment. The same components as those in the first embodiment will be described using the same reference numerals, and the description here will be omitted. The sterilization device 1 of the second embodiment differs from the first embodiment mainly in that a photocatalyst 11 is further provided at a position where the ultraviolet light irradiated from the ultraviolet light irradiation unit 20 reaches the sterilization unit 10.

[0046] (Sterilization unit) As shown in Fig. 2, the sterilization unit 10 is attached to the duct side wall 103a with a portion of the duct side wall that forms the air passage 2 through which the air sent out toward the air outlet 105a flows being cut out. The ultraviolet light irradiation unit 20 is fixed so that the air passage side is in contact with the air flowing in the air passage. At the opposite position in the duct 103, the photocatalyst 11 is provided along the inner wall so as to face the second surface 21d. The direction indicated by the arrow in Fig. 7 is the movement direction F of the air flowing from the upstream side (intake side) to the downstream side (air outlet side). Air flows through the space between the ultraviolet light irradiation unit 20 and the photocatalyst 11.

[0047] (Photocatalyst) The photocatalyst 11 is fixed by four fixing legs 13. The fixing legs 13 are provided at each corner portion of the fixing frame 29 of the ultraviolet light irradiation unit 20, i.e., at the four corners located near the side wall of the duct 104, and extend from the fixing frame 29 toward the inner wall on the opposite side of the duct 104. In FIG. 7, the photocatalyst 11 fixed by the fixing legs 13 is in contact with the inner wall of the duct. The photocatalyst 11 may be made by firing the photocatalyst material 12, or by supporting the photocatalyst material 12 on other materials such as metal or ceramic. The photocatalyst material 12 may be movably accommodated in a mesh case that accommodates crystal grains of the photocatalyst material 12 inside.

[0048] (Photocatalyst material) The photocatalytic material 12 may be, for example, titanium oxide. When light is irradiated onto the photocatalytic material 12 such as titanium oxide, radicals are generated, and these radicals decompose organic matter. Various materials other than titanium oxide may be used as long as they are capable of performing such photodecomposition. It is known that titanium oxide has three types of crystal forms: rutile type, anatase type, and brookite type, but the anatase type is mainly used. For example, anatase type titanium dioxide calcined at 600°C may be movably accommodated and supported in a 60 mesh stainless steel case.

[0049] In the sterilization device 1 of the present embodiment, the photocatalyst is provided at the location where the ultraviolet light is irradiated, so that deodorization can be performed by photocatalysis. That is, decomposition of organic matter by photolysis can be promoted, and the deodorization effect by photocatalysis can be enhanced in addition to the sterilization effect by irradiation of ultraviolet light on suspended matter in the air. In addition, since the ultraviolet light irradiation unit and the photocatalyst can be made thin and compact, it is possible to provide a sterilization device that can be easily installed and can be attached to the wall surface constituting the air passage. In addition, as the multiple ultraviolet LEDs used in the ultraviolet light irradiation unit 20, two types of ultraviolet LEDs 23a and 23b that emit light of different wavelengths are arranged. The first UV-LED 23a is an LED light source that emits a wavelength range of UV-C and is made to be highly efficient mainly in sterilizing bacteria in the air. It is preferable to select the second UV-LED 23b as a wavelength range that has a sterilization effect on bacteria, etc. different from the first UV-LED 23a, or a wavelength suitable for exciting the photocatalyst. For example, an LED light source that emits UV-A wavelengths is used.

[0050] Although the embodiment and the modified examples of the present invention have been described above, the above embodiment and the modified examples are merely examples in every respect. The present invention is not to be interpreted in a limited manner by these descriptions. The present invention can be modified in various other ways without departing from the spirit thereof. For example, in the second embodiment, the photocatalyst 11 is provided so as to face the second surface 21d, but the photocatalyst 11 may be provided so as to face the second end surface 21b, which is the side surface of the light guide member 21. When the photocatalyst 11 is provided so as to face the second end surface 21b, the ultraviolet light irradiation unit 20 and the photocatalyst 11 can be provided as a sterilization unit located in the same plane, so that the sterilization unit 10 can be fixed to ducts of various diameters without considering the thickness of the duct, and the installation can be performed even more easily. The sterilization unit can be easily installed by simply cutting out a size that allows the ultraviolet light irradiation unit 20 and the photocatalyst 11 arranged in the same plane on either side of the duct, so that it can be easily installed even after the fact. In addition, because it is small, it can be applied not only to air conditioners for automobiles, but also to various types of air blowers, such as indoor air conditioners and portable blowers, as long as they have an air passageway.

[0051] In the above-mentioned embodiment and its modified example, the sterilization device is incorporated in the duct of the air conditioner, but the target to be irradiated with ultraviolet light is not limited to air. It can also be applied to sterilization of gases other than air, for example, oxygen gas. In addition, even if the fluid other than gas, for example, liquid, is attached to the wall surface of a duct (fluid passage) through which the fluid flows, it can exhibit a sterilization effect. Since the sterilization device of the present invention is configured to use a light guiding member, it is possible to provide a sterilization device that can be easily installed even after the device is installed, while making the depth dimension of the device compact. [Industrial Applicability]

[0052] In automobile air conditioners, indoor air conditioners, blowers, and other places with various air passages, and in fluid passages where other fluids flow Also suitable Can be used. [Explanation of symbols]

[0053] 1. Sterilization device 2...Air passage 3...Air intake port 4…Discharge port 10…Sterilization unit 11...Photocatalyst 12...Photocatalyst material 13…Fixed leg 20…Ultraviolet light irradiation unit 21...Light guiding member 21b…Second end face (output side) 21d…Second surface (output surface) 23…Ultraviolet LED 24…LED mounting board 25...Reflective material 26...Scattered area 27…Mounting part 29…Fixed frame 30...Visible light emitting unit 31…Visible LED light source 32... Visible LED lighting control unit 33...Printed circuit board 34...Storage frame body 100...Air conditioner 103, 104...Duct (air passage) 103a…Duct side wall 105a, 105b…Air outlet F…Air movement direction UV1…Emitted light UV2…Outgoing light UV3…Emitted light

Claims

1. A sterilization apparatus including a sterilization unit attached to an air passage between an inlet for introducing air and an outlet for discharging air, the air passage having the inlet and the outlet, the sterilization unit has an ultraviolet light irradiation unit including a plate-shaped light guide member arranged along a moving direction of air flowing through the air passage and an attachment part for fixing the ultraviolet light irradiation unit to the air passage, The ultraviolet light irradiation unit includes a plurality of ultraviolet LEDs arranged to face one end face of the light guide member, an LED mounting substrate on which the plurality of ultraviolet LEDs are mounted in a row, a reflecting member that covers a surface of the light guide member opposite to the air passage side, and a fixing frame that fixes the light guide member, the light guide member has a first surface located on the opposite side to the air passage, a second surface located on the air passage side, a first end face facing the LED mounting board, and a second end face located on the opposite side to the first end face; the reflecting member is a metal sheet having a reflecting surface in close contact with the first surface and covering the entire first surface; the fixing frame has an opening that covers a corner portion of the second end surface of the light guiding member and exposes a central portion of the second end surface, and is made of a metal material provided along an edge of the second surface, the fixing frame and the reflecting member sandwich the light guiding member, the second surface and the second end surface are configured as emission surfaces from which light emitted from the ultraviolet LED and guided through the light-guiding member is emitted, the attachment portion is formed so as to be fixable to a rear surface of a duct forming the air passage such that the emission surface is exposed in the air passage, The LED mounting board is located downstream of the air passage, A sterilization device in which light emitted from the ultraviolet LED, entered the light-guiding member, and exited from the exit surface is ultraviolet light that exits through the second end face toward the upstream side, and ultraviolet light that exits through the second surface is exited in an oblique direction from the downstream side to the upstream side of the air passage.

2. The sterilization unit includes a photocatalytic material that is excited by light having an emission wavelength of the ultraviolet LED, The sterilization device according to claim 1 , wherein a photocatalyst containing the photocatalytic substance is provided in the air passage at a position facing the second surface.

3. A sterilization device as described in claim 1 or 2, characterized in that the multiple LEDs include an LED that emits ultraviolet light in the UV-C range.

4. A sterilization device described in any of claims 1 to 3, wherein the first surface has a plurality of scattering regions with uneven shapes at the boundary between the first surface and the reflective member.

5. A visible light emitting unit is provided on the opposite side of the LED mounting substrate to the light guide member, the visible light emitting unit includes a visible LED light source capable of emitting a single color or a plurality of colors, and a visible LED lighting control unit that controls lighting of the visible LED light source; 5. The sterilization apparatus according to claim 1, wherein the visible LED lighting control unit starts lighting the visible LED light source in synchronization with lighting of the ultraviolet LED.

6. A sterilization device described in any of claims 1 to 5, wherein the second surface and the second end face protrude into the air passage from the duct.

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