JP7595352B2 - Sterilization device and sterilization method - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act Irie Yasuo (Published at Kitakyushu Performing Arts Center Small Theater IoT Maker's Project DemoDay) March 26, 2021 Kadokawa ASCII Research Laboratories, Inc. (Published on the Kadokawa ASCII Research Laboratories, Inc. website) March 30, 2021 Kitakyushu City Industrial and Economic Bureau Startup Promotion Division (Published on YouTube) March 31, 2021 PR TIMES Inc. (Published on the PR TIMES Inc. website) March 31, 2021 Kitakyushu City Industrial and Economic Bureau Startup Promotion Division (Published on the Kitakyushu City website) March 31, 2021 Kadokawa ASCII Research Laboratories, Inc. (Published on the Kadokawa ASCII Research Laboratories, Inc. website) August 6, 2021

The present invention relates to a sterilization device and a sterilization method for sterilizing outside air.

It is known that ozone (O 3 ) and hydroxyl radicals (OH radicals) can be used to sterilize airborne bacteria floating in indoor spaces such as warehouses for storing food and clothing, storage facilities for storing grains, containers and carriers for transporting food and grains, hospitals, government offices, hotels, etc., and bacteria attached to stored objects, walls, etc. _Ozone has a strong sterilizing effect, but it also has the risk of adversely affecting the human body. For this reason, various standards have been established, such as keeping the ozone concentration in spaces where people are present at 0.1 ppm or less, and prohibiting people from entering warehouses when sterilizing the inside of warehouses with high concentrations of ozone of about 10 ppm. Hydroxyl radicals are also characterized by their high reactivity, but their very short life span of about 10 ⁻⁶ seconds.

Patent document 1 discloses a self-propelled functional ingredient generator that uses a drive unit to move a functional ingredient generator that simultaneously generates ozone and hydroxyl radicals by discharging, sterilizing an area. The movement speed of this device is adjusted so that the ozone concentration at a specified point in the area does not exceed a specified value (e.g., 0.05 ppm).

JP 2011-188950 A

However, because the device in Patent Document 1 controls the ozone concentration in the air by the movement speed, it cannot be installed in a fixed location indoors, and it is also difficult to freely change the ozone concentration depending on the application, so there is room for further improvement in order to flexibly sterilize according to the application.

The present invention aims to provide a sterilization device and a sterilization method that can flexibly sterilize outside air.

The sterilization device of the present invention is a sterilization device that sterilizes outside air, and comprises a fan section that takes in outside air, an ozone generating section that generates ozone, a hydroxyl radical generating section that generates hydroxyl radicals from ozone, a control section that controls the ozone generating section and the hydroxyl radical generating section, and a member that guides gas that has passed through the ozone generating section to the hydroxyl radical generating section, and the outside air taken in by the fan section is passed through the ozone generating section and the hydroxyl radical generating section in that order, and released to the outside .

The sterilization method of the present invention is a sterilization method using a sterilization device that sterilizes outside air, the sterilization device comprises an ozone generating unit that generates ozone, a hydroxyl radical generating unit that generates hydroxyl radicals from ozone, and a member that guides gas that has passed through the ozone generating unit to the hydroxyl radical generating unit, and includes an ozone generating step of generating ozone from the outside air taken into the sterilization device in the ozone generating unit, an ozone releasing step of releasing the generated ozone to the outside of the sterilization device, an external sterilization step of sterilizing the external space of the sterilization device with the ozone released to the outside, and an ozone decomposition step of generating hydroxyl radicals from the ozone remaining in the sterilized outside air taken into the sterilization device and decomposing the ozone in the hydroxyl radical generating unit .

Another sterilization method of the present invention is a sterilization method using a sterilization device that sterilizes outside air, the sterilization device comprises an ozone generating unit that generates ozone, a hydroxyl radical generating unit that generates hydroxyl radicals from ozone, and a member that guides gas that has passed through the ozone generating unit to the hydroxyl radical generating unit, and includes an ozone generating step in the ozone generating unit to generate ozone from the outside air taken into the sterilization device, an internal sterilization step in the ozone generating unit to sterilize the outside air with the ozone, and a hydroxyl radical generating step in the hydroxyl radical generating unit to generate hydroxyl radicals from the ozone remaining after sterilization.

The present invention allows for flexible sterilization of outside air.

FIG. 1 is a perspective view of an automatic traveling sterilization device according to an embodiment of the present invention; FIG. 1 is a side view illustrating an outline of an automatic traveling sterilization device according to an embodiment of the present invention. FIG. 1 is an exploded view of a sterilization device according to an embodiment of the present invention. An exploded view of an ozone generating unit of a sterilizer according to one embodiment of the present invention. FIG. 1 is an exploded view of a hydroxyl radical generating unit of a sterilization device according to an embodiment of the present invention. FIG. 1 is a side cross-sectional view of a sterilization device according to an embodiment of the present invention. FIG. 1 is a horizontal cross-sectional view of a hydroxyl radical generating section of a sterilization device according to an embodiment of the present invention; FIG. 1 is a block diagram showing the configuration of a control system of a sterilization apparatus according to an embodiment of the present invention. FIG. 1 is an explanatory diagram of the function of a sterilization device according to an embodiment of the present invention. FIG. 1 is a perspective view of another embodiment of the automatic traveling type sterilization device according to the present invention; (a) An explanatory diagram of an ozone release process and (b) an explanatory diagram of an ozone decomposition process by an automatic traveling sterilization device installed in a warehouse according to one embodiment of the present invention. FIG. 1 is an explanatory diagram of an ozone release process and an ozone decomposition process of a sterilization device installed in a warehouse according to an embodiment of the present invention. FIG. 1 is an explanatory diagram of a sterilization method using a sterilization device installed in a refrigerated storage unit according to an embodiment of the present invention.

One embodiment of the present invention will be described in detail below with reference to the drawings. The configurations, shapes, etc. described below are examples for the purpose of explanation, and can be modified as appropriate depending on the specifications of the sterilization device and the automatic driving unit (automatic transport vehicle). In the following, corresponding elements in all drawings will be given the same reference numerals, and duplicate explanations will be omitted.

First, the configuration of the automatic traveling sterilization device 1 will be described with reference to Figures 1 and 2. The automatic traveling sterilization device 1 includes an automatic traveling unit 2 and a sterilization device 3 installed on the upper part of the automatic traveling unit 2. The automatic traveling unit 2 includes an environment measurement sensor 2a such as a laser range scanner or an infrared distance sensor, an input unit 2b, and a traveling control unit 2c. The automatic traveling unit 2 is an automatic guided vehicle that travels (self-propels) autonomously (self-propels) by the traveling control unit 2c while the environment measurement sensor 2a measures the surrounding environment such as the distance and position to surrounding walls and obstacles. The automatic traveling unit 2 may be an automatic guided vehicle of a SLAM (Simultaneous Localization And Mapping) type equipped with the environment measurement sensor 2a, a line tracing type that travels while reading a tape installed on the floor, or a landmark reading type that recognizes its position by reading a sticker installed on the floor.

Commands and the like are input from the input unit 2b to the automatic driving unit 2 and the sterilization device 3. In FIG. 1, the input unit 2b is shown as having a plurality of buttons, but the input unit 2b may be configured to have other input means such as a touch panel. In addition, the input unit 2b may be configured to input and output various commands and information via wireless communication using infrared rays or radio waves.

In FIG. 2, the sterilizer 3 comprises a main body 4 and an outer cylinder 5 that protrudes upward from the top of the main body 4. A plurality of intake ports 4a are formed on the outer circumferential surface of the main body 4 to take in outside air into the inside of the main body 4. The outer cylinder 5 is a hollow cylinder with openings at the top and bottom, and is made of a metal such as aluminum that has high thermal conductivity. A fan unit 6 is disposed on the top of the main body 4 that communicates with the outer cylinder 5. A control unit 7 is disposed inside the main body 4. The fan unit 6 comprises a fan 6a and a fan motor 6b that rotates the fan 6a (FIG. 6). The fan motor 6b is driven (power is supplied) by a fan drive unit 6c that is controlled by the control unit 7 (FIG. 8).

Inside the outer cylinder 5, an ozone generator 10 that generates ozone and a hydroxyl radical generator 20 that generates hydroxyl radicals from ozone are arranged. At the top of the sterilizer 3, an exhaust port 3a is formed through which the ozone generated by the ozone generator 10 is exhausted (discharged). When the fan 6a rotates, outside air is taken into the inside of the main body 4 through the intake port 4a (arrow a in FIG. 9), and the taken-in outside air is sent to the ozone generator 10 (arrows b to c in FIG. 9). The gas that passes through the ozone generator 10 and the hydroxyl radical generator 20 in order (arrows d to f in FIG. 9) is discharged to the outside from the exhaust port 3a that opens at the top of the sterilizer 3 (arrow g in FIG. 9).

In Figures 2 and 8, an inlet sensor 8, which is an ozone sensor that measures the concentration of ozone contained in the inhaled outside air, is placed near the inlet 4a. An outlet sensor 9, which is an ozone sensor that measures the concentration of ozone contained in the exhausted gas, is placed near the exhaust 3a. The inlet sensor 8 and outlet sensor 9 are connected to the control unit 7, and the measurement results of the inlet sensor 8 and outlet sensor 9 are sent to the control unit 7 (Figure 8). In this way, the sterilization device 3 is equipped with a fan unit 6 that takes in outside air, and ozone sensors (inlet sensor 8, outlet sensor 9) that measure the ozone concentration.

Next, the ozone generating unit 10 and the hydroxyl radical generating unit 20 of the sterilization device 3 will be described in detail with reference to Figures 3 to 7. Figures 3 to 5 are exploded views of the sterilization device 3. Figure 6 is a cross-sectional view taken along line C-C in Figure 7(a) showing the sterilization device 3 from the side. Figure 7(a) is a cross-sectional view taken along line A-A in Figure 6 showing the hydroxyl radical generating unit 20 of the sterilization device 3 from above. Figure 7(b) is a cross-sectional view taken along line B-B in Figure 6 showing the ozone generating unit 10 of the sterilization device 3 from above.

3, 6, and 7, an inner cylinder 30 and multiple heat dissipation members 31 are arranged inside 5a of outer cylinder 5. Inner cylinder 30 is a hollow cylinder with openings at the top and bottom, and is made of a material such as silicon that is resistant to ozone and hydroxyl radicals. A skirt member 30a is arranged at the bottom of inner cylinder 30 to guide outside air blown from fan unit 6 to inside 30b (FIG. 4) of inner cylinder 30. Heat dissipation member 31 is made of metal such as aluminum with high thermal conductivity, and has a shape with high heat dissipation such as fins. Heat dissipation member 31 is attached to the outer surface of inner cylinder 30, and conducts heat generated in inner cylinder 30 to outer cylinder 5, dissipating heat from outer cylinder 5 to the outside.

In Figures 4, 6, and 7(b), the first air guide member 11 and the vacuum ultraviolet ray irradiation section 12 are arranged on the lower side of the inside 30b of the inner tube section 30. The first air guide member 11 is a hollow cylinder with a sealed upper part and an open lower part, and has multiple ventilation holes 11b formed on the side. The first air guide member 11 is made of a material such as plastic. A skirt member 11a is arranged on the lower part of the first air guide member 11, which guides the outside air blown from the fan section 6 into the inside of the first air guide member 11. Hereinafter, the inside of the first air guide member 11 is referred to as the central section 10a of the ozone generating section 10.

The vacuum ultraviolet ray irradiation unit 12 has a function of irradiating vacuum ultraviolet rays (VUV) containing ultraviolet rays with a wavelength of around 185 nm as a main component. The vacuum ultraviolet ray irradiation unit 12 is composed of, for example, a plasma discharge body, a mercury lamp, an excimer lamp, a UV-LED (light-emitting diode), etc. In this embodiment, an example in which the vacuum ultraviolet ray irradiation unit 12 is composed of three plate-shaped plasma discharge bodies will be described. The vacuum ultraviolet ray irradiation unit 12 is supplied with power by a vacuum ultraviolet ray power supply unit 12a controlled by the control unit 7 (Figure 8). When power is supplied from the vacuum ultraviolet ray power supply unit 12a, vacuum ultraviolet rays are irradiated from the vacuum ultraviolet ray irradiation unit 12. The amount of vacuum ultraviolet rays irradiated from the vacuum ultraviolet ray irradiation unit 12 can be changed by controlling the magnitude of the power supplied from the vacuum ultraviolet ray power supply unit 12a.

6 and 7(b), the vacuum ultraviolet ray irradiation unit 12 is arranged around the first air guide member 11 so that the vacuum ultraviolet ray is irradiated toward the first air guide member 11. When the vacuum ultraviolet ray irradiation unit 12 is composed of a flexible plasma discharge body, one plasma discharge body may be arranged so as to cylindrically surround the first air guide member 11. Hereinafter, the space between the first air guide member 11 and the vacuum ultraviolet ray irradiation unit 12 is referred to as the peripheral portion 10b of the ozone generation unit 10.

The outside air sent from the fan unit 6 to the central part 10a of the ozone generating unit 10 (arrow c in FIG. 9) is sent through the ventilation opening 11b to the peripheral part 10b of the ozone generating unit 10 (arrow d in FIG. 9). A part of the oxygen ( _O2 ) contained in the outside air sent to the peripheral part 10b absorbs the vacuum ultraviolet ray irradiated from the vacuum ultraviolet ray irradiation unit 12 and changes to ozone ( _O3 ). In this way, the inner tube unit 30, the first air guide member 11, and the vacuum ultraviolet ray irradiation unit 12 have the vacuum ultraviolet ray irradiation unit 12 that irradiates vacuum ultraviolet ray, and constitute the ozone generating unit 10 that generates ozone.

In Figures 5, 6, and 7(a), the second air guide member 21, the near-ultraviolet ray irradiation section 22, and the light shielding member 32 are arranged on the upper side of the inside 30b of the inner tube section 30. The second air guide member 21 is a hollow cylinder with a sealed upper part and an open lower part, and has multiple ventilation holes 21b formed on the side. The second air guide member 21 is made of a material such as plastic. A skirt member 21a is arranged on the lower part of the second air guide member 21, which guides the ozone-containing gas blown from the ozone generating section 10 into the inside of the second air guide member 21. Hereinafter, the inside of the second air guide member 21 is referred to as the central section 20a of the hydroxyl radical generating section 20.

The near-ultraviolet ray irradiation unit 22 has a function of irradiating near-ultraviolet rays (UVC) whose main component is ultraviolet rays with a wavelength of around 254 nm. The near-ultraviolet ray irradiation unit 22 is composed of, for example, a plasma discharge body, a mercury lamp, an excimer lamp, a UV-LED (light-emitting diode), etc. In this embodiment, an example in which the near-ultraviolet ray irradiation unit 22 is composed of a flexible plate-shaped plasma discharge body will be described. The near-ultraviolet ray irradiation unit 22 is supplied with power by a near-ultraviolet ray power supply unit 22a controlled by the control unit 7 (FIG. 8). When power is supplied from the near-ultraviolet ray power supply unit 22a, near-ultraviolet rays are irradiated from the near-ultraviolet ray irradiation unit 22. The amount of near-ultraviolet rays irradiated from the near-ultraviolet ray irradiation unit 22 can be changed by controlling the magnitude of the power supplied from the near-ultraviolet ray power supply unit 22a.

In Figures 6 and 7(a), the plasma discharge body of the near-ultraviolet ray irradiation section 22 is arranged so as to cylindrically surround the second air guide member 21 so that near-ultraviolet rays are irradiated toward the second air guide member 21. When the near-ultraviolet ray irradiation section 22 is composed of multiple plate-shaped plasma discharge bodies, the multiple plasma discharge bodies are arranged so as to surround the second air guide member 21. Hereinafter, the space between the second air guide member 21 and the near-ultraviolet ray irradiation section 22 is referred to as the peripheral portion 20b of the hydroxyl radical generating section 20.

The gas sent from the ozone generating section 10 to the central section 20a of the hydroxyl radical generating section 20 (arrow e in FIG. 9) is sent through the ventilation opening 21b to the peripheral section 20b of the hydroxyl radical generating section 20 (arrow f in FIG. 9). A part of the ozone (O ₃ ) contained in the gas sent to the peripheral section 20b absorbs the near-ultraviolet rays irradiated from the near-ultraviolet ray irradiation section 22 and combines with the water (H ₂ O) contained in the gas to become hydroxyl radicals (OH radicals). In this way, the inner tube section 30, the second air guide member 21, and the near-ultraviolet ray irradiation section 22 constitute the hydroxyl radical generating section 20 that has the near-ultraviolet ray irradiation section 22 that irradiates near-ultraviolet rays and generates hydroxyl radicals from ozone.

In Figures 5 and 6, the light shielding member 32 is arranged at the upper end of the inner tube portion 30 and has a mortar shape with its center portion projecting into the interior of the inner tube portion 30, and an opening 32a is formed in the center to release gas from the hydroxyl radical generating portion 20 to the outside. The light shielding member 32 has a light shielding function to prevent near-ultraviolet rays irradiated from the near-ultraviolet rays irradiating portion 22 of the hydroxyl radical generating portion 20 from leaking outside the sterilization device 3. In other words, the shapes and arrangements of the light shielding member 32, inner tube portion 30, second air guide member 21, and near-ultraviolet rays irradiated from the near-ultraviolet rays irradiating portion 22 are designed so that the near-ultraviolet rays irradiated from the near-ultraviolet rays irradiating portion 22 do not leak outside the sterilization device 3.

3, 6, and 7, in this embodiment, the ozone generating section 10 and the hydroxyl radical generating section 20 are arranged inside the inner cylinder section 30, a heat dissipation member 31 is attached to the outer periphery of the inner cylinder section 30, and the outer cylinder section 5 surrounds the ozone generating section 10 and the hydroxyl radical generating section 20. This prevents the inner cylinder section 30 from corroding due to ozone and hydroxyl radicals, and realizes a configuration capable of dissipating heat generated from the vacuum ultraviolet ray irradiation section 12 and the near ultraviolet ray irradiation section 22 to the outside. The outer shell section that configures the ozone generating section 10 and the hydroxyl radical generating section 20 inside is not limited to the configuration consisting of the inner cylinder section 30, the heat dissipation member 31, and the outer cylinder section 5. In other words, it is sufficient if it is configured to prevent corrosion due to ozone and hydroxyl radicals while dissipating heat to the outside. For example, cylindrical aluminum with a thin film of aluminum oxide formed on the surface by anodizing, or cylindrical metal with a thin film of chromium or gold formed on the surface by plating may be used as the outer shell section. Additionally, the shape of the outer shell does not have to be cylindrical, but can be a square prism or a flat cubic prism.

Next, the configuration of the control system of the sterilizer 3 and the function of the sterilizer 3 will be described with reference to Figures 8 and 9. Figure 8 is a block diagram showing the configuration of the control system of the sterilizer 3. In the case of the self-driving sterilizer 1, it further includes a driving control unit 2c that controls the self-driving unit 2, and the control unit 7 and the driving control unit 2c work together to execute the sterilization process described below. In addition, while Figure 1 describes a configuration in which the self-driving unit 2 includes the input unit 2b, Figure 8 describes a configuration in which the sterilizer 3 includes the input unit 2b. Figure 9 shows a schematic diagram of the inside of the sterilizer 3, and for convenience, the vacuum ultraviolet ray irradiation unit 12 of the ozone generation unit 10, the near ultraviolet ray irradiation unit 22 of the hydroxyl radical generation unit 20, the control unit 7 arranged in the main body unit 4, the fan drive unit 6c, the vacuum ultraviolet ray power supply unit 12a, the near ultraviolet ray power supply unit 22a, the intake port sensor 8, and the exhaust port sensor 9 are omitted.

In FIG. 8, the control unit 7 of the sterilizer 3 is connected to the input unit 2b, the intake sensor 8, the exhaust sensor 9, the fan drive unit 6c, the vacuum ultraviolet power supply unit 12a, and the near-ultraviolet power supply unit 22a. Based on the command input from the input unit 2b, the control unit 7 controls the fan drive unit 6c, the vacuum ultraviolet power supply unit 12a, and the near-ultraviolet power supply unit 22a according to the ozone concentration near the intake port 4a measured by the intake sensor 8 and the ozone concentration near the exhaust port 3a measured by the exhaust sensor 9, to execute sterilization processing in multiple modes. Specifically, the sterilizer 3 has a high-concentration ozone release mode, an ozone decomposition mode, a low-concentration ozone release mode, and an internal sterilization mode.

8 and 9, the high-concentration ozone release mode is a mode in which gas containing high-concentration ozone of about 10 ppm is released to the outside from the exhaust port 3a to sterilize attached and floating bacteria in the external space. In this mode, the control unit 7 controls the vacuum ultraviolet ray irradiation unit 12 to increase the amount of vacuum ultraviolet ray irradiation, and the near-ultraviolet ray irradiation unit 22 to irradiate no near-ultraviolet ray or to irradiate a small amount of near-ultraviolet ray. The ozone generation unit 10 irradiates the outside air (arrow d) sent to the peripheral portion 10b of the ozone generation unit 10 with strong vacuum ultraviolet ray to generate high-concentration ozone (high-concentration ozone generation process). Then, the hydroxyl radical generation unit 20 releases gas containing high-concentration ozone to the outside from the exhaust port 3a (arrow g) (high-concentration ozone release process) without decomposing ozone. Based on the concentration of ozone measured by the ozone sensors (inlet sensor 8, outlet sensor 9), the control unit 7 controls the rotation speed of the fan unit 6, the amount of vacuum ultraviolet light emitted from the vacuum ultraviolet light irradiation unit 12, and the amount of near-ultraviolet light emitted from the near-ultraviolet light irradiation unit 22 so that the ozone concentration of the gas released to the outside from the outlet 3a becomes a predetermined value.

In the ozone decomposition mode, outside air containing high concentrations of ozone is taken in through the intake port 4a, the ozone is decomposed, and then released to the outside through the exhaust port 3a, thereby lowering the ozone concentration in the outside air. In this mode, the control unit 7 controls the vacuum ultraviolet ray irradiation unit 12 not to irradiate vacuum ultraviolet rays, and the near-ultraviolet ray irradiation unit 22 to irradiate a large amount of near-ultraviolet rays. In the hydroxyl radical generating unit 20, the gas containing ozone sent to the peripheral unit 20b (arrow f) is irradiated with strong near-ultraviolet rays to generate hydroxyl radicals from the remaining ozone (ozone decomposition process). That is, the hydroxyl radical generating unit 20 decomposes the remaining ozone. After that, the gas in which the residual ozone has been decomposed in the hydroxyl radical generating unit 20 is released to the outside through the exhaust port 3a (arrow g).

8 and 9, the low-concentration ozone release mode is a mode in which gas containing low-concentration ozone of about 0.1 ppm is released to the outside from the exhaust port 3a to sterilize attached and floating bacteria in the external space. In this mode, the control unit 7 controls the vacuum ultraviolet ray irradiation unit 12 to reduce the amount of vacuum ultraviolet ray irradiation, and the near-ultraviolet ray irradiation unit 22 to irradiate no near-ultraviolet ray or to irradiate a small amount of near-ultraviolet ray. The ozone generation unit 10 irradiates the outside air (arrow d) sent to the peripheral portion 10b of the ozone generation unit 10 with weak vacuum ultraviolet ray to generate low-concentration ozone (low-concentration ozone generation process). Then, the hydroxyl radical generation unit 20 releases gas containing low-concentration ozone to the outside from the exhaust port 3a (arrow g) (low-concentration ozone release process) without decomposing ozone. Based on the concentration of ozone measured by the ozone sensors (inlet sensor 8, outlet sensor 9), the control unit 7 controls the rotation speed of the fan unit 6, the amount of vacuum ultraviolet light emitted from the vacuum ultraviolet light irradiation unit 12, and the amount of near-ultraviolet light emitted from the near-ultraviolet light irradiation unit 22 so that the ozone concentration of the gas released to the outside from the outlet 3a becomes a predetermined value.

In Figures 8 and 9, the internal sterilization mode is a mode in which airborne bacteria in the external space are taken into the sterilization device 3 and sterilized with high-concentration ozone and hydroxyl radicals. In this mode, the control unit 7 controls the vacuum ultraviolet ray irradiation unit 12 to increase the amount of vacuum ultraviolet ray irradiation, and the near-ultraviolet ray irradiation unit 22 to increase the amount of near-ultraviolet ray irradiation. The ozone generation unit 10 irradiates the outside air (arrow d) sent to the peripheral area 10b of the ozone generation unit 10 with strong vacuum ultraviolet ray to generate high-concentration ozone (high-concentration ozone generation process). The ozone generation unit 10 sterilizes airborne bacteria contained in the outside air with the generated high-concentration ozone (internal sterilization process).

Then, the gas containing high concentration ozone (arrow f) sent to the peripheral portion 20b of the hydroxyl radical generating portion 20 is irradiated with strong near-ultraviolet rays to generate hydroxyl radicals from the ozone remaining after sterilization (hydroxyl radical generating process). As hydroxyl radicals are generated, the concentration of the remaining ozone decreases. In the hydroxyl radical generating portion 20, the generated hydroxyl radicals sterilize the airborne bacteria contained in the gas sent from the ozone generating portion 10. Then, the gas in the hydroxyl radical generating portion 20 is discharged to the outside from the exhaust port 3a (arrow g). By controlling the amount of near-ultraviolet rays irradiated from the near-ultraviolet irradiating portion 22, it is also possible to make the gas discharged from the exhaust port 3a contain (remain) low concentration ozone. That is, in the hydroxyl radical generating process, hydroxyl radicals are generated from ozone and at the same time, a predetermined concentration of ozone is left and discharged to the outside of the sterilization device 3. The hydroxyl radicals discharged from the exhaust port 3a disappear in a very short time, so they do not diffuse far from the sterilization device 3.

In each mode, the control unit 7 controls the amount of gas discharged to the outside by the rotation speed of the fan 6a. The control unit 7 also controls the concentration of ozone generated by the amount of vacuum ultraviolet light and near ultraviolet light irradiated from the vacuum ultraviolet light irradiating unit 12 and near ultraviolet light irradiating unit 22 based on the measurement results of the inlet sensor 8 and the outlet sensor 9. In this way, the sterilization device 3 is equipped with the control unit 7 that controls the ozone generating unit 10 and the hydroxyl radical generating unit 20, and the control unit 7 controls the amount of vacuum ultraviolet light irradiated by the vacuum ultraviolet light irradiating unit 12 and the amount of near ultraviolet light irradiated by the near ultraviolet light irradiating unit 22 according to the concentration of ozone discharged to the outside. Note that the sterilization device 3 does not necessarily need to be equipped with the inlet sensor 8 and the outlet sensor 9. For example, it may be configured to include either the inlet sensor 8 or the outlet sensor 9, or it may be configured to include neither. When the inlet sensor 8 and the outlet sensor 9 are not provided, the control unit 7 controls each unit in a predetermined pattern.

Next, referring to FIG. 10, another embodiment of the self-traveling sterilizer will be described. The self-traveling sterilizer 1A of the other embodiment is equipped with multiple (four in this case) sterilizers 3 on top of the self-traveling section 2. That is, the self-traveling sterilizer 1A (sterilizer) is equipped with multiple ozone generators 10 and multiple hydroxyl radical generators 20. This makes it possible to increase the amount of outside air that can be sterilized per unit time.

Next, referring to FIG. 11, a method of sterilizing a warehouse 40 using an automatic sterilizing device 1 (sterilizing device) will be described. A plurality of shelves 41 are installed in the warehouse 40, and the automatic sterilizing device 1 travels on the floor 42 between the shelves 41. First, a sterilizing method of prohibiting people from entering the warehouse 40 and sterilizing the warehouse space 43 with high concentration ozone will be described. In FIG. 11(a), first, the automatic sterilizing device 1 travels along the shelves 41 on the floor 42 in high concentration ozone emission mode (arrow h). The high concentration ozone released from the automatic sterilizing device 1 sterilizes the attached bacteria on the shelves 41 and the airborne bacteria in the warehouse space 43. In FIG. 11(b), before a person enters the warehouse space 43, the automatic sterilizing device 1 travels thoroughly on the floor 42 while frequently changing direction in ozone decomposition mode (arrow i), reducing the residual ozone concentration in the warehouse space 43 to a predetermined concentration.

In this way, the sterilization method using the self-traveling sterilization device 1 (sterilization device) that sterilizes outside air involves the self-traveling sterilization device 1 moving (arrow h) through the area to be sterilized (floor 42) while generating ozone from the outside air taken in by the self-traveling sterilization device 1 (ozone generation process), releasing the generated ozone to the outside of the self-traveling sterilization device 1 (ozone release process), and sterilizing the external space (warehouse space 43) of the self-traveling sterilization device 1 with the ozone released to the outside (external sterilization process). After that, as the self-traveling sterilization device 1 moves through the area (arrow i), it generates hydroxyl radicals from the ozone remaining in the sterilized outside air taken in by the self-traveling sterilization device 1, and decomposes the ozone (ozone decomposition process).

Next, referring to FIG. 11, a sterilization method for sterilizing the space 43 inside the warehouse 40 with ozone without prohibiting people from entering the warehouse 40 will be described. In this case, the self-traveling sterilization device 1 travels on the floor 42 between the shelves 41 in low-concentration ozone release mode (arrow h or arrow i). That is, the self-traveling sterilization device 1 performs the ozone generation process, the ozone release process, and the external sterilization process while moving through the area (floor 42) to be sterilized. Alternatively, the self-traveling sterilization device 1 travels on the floor 42 between the shelves 41 in internal sterilization mode (arrow h or arrow i). That is, the self-traveling sterilization device 1 performs the ozone generation process, the internal sterilization process of sterilizing the outside air with ozone inside the self-traveling sterilization device 1, and the hydroxyl radical generation process of generating hydroxyl radicals from the ozone remaining after sterilization while moving through the area (floor 42) to be sterilized.

Next, referring to FIG. 12, a method for sterilizing the warehouse 40 using the sterilizing device 3 installed inside the warehouse 40 will be described. The configuration of the warehouse 40 is the same as that in FIG. 11. In FIG. 12, three sterilizing devices 3 are arranged at fixed positions inside the warehouse 40. The sterilizing devices 3 are connected to the controller 44 via a communication network 45.

First, a sterilization method is described in which people are prohibited from entering the warehouse 40 and the warehouse space 43 is sterilized with high concentration ozone. In FIG. 12(a), the controller 44 sets the sterilization device 3 to a high concentration ozone release mode and causes the sterilization device 3 to release high concentration ozone into the warehouse space 43 (arrow j). In FIG. 12(b), before a person enters the warehouse space 43, the controller 44 changes the sterilization device 3 to an ozone decomposition mode and reduces the residual ozone concentration in the warehouse space 43 to a predetermined concentration (arrow k). In this way, the sterilization method using the sterilization device 3 to sterilize the outside air executes an ozone generation process, an ozone release process, and an external sterilization process, and executes an ozone decomposition process after a predetermined time has passed.

Next, a sterilization method for sterilizing the warehouse space 43 with low-concentration ozone without prohibiting people from entering or leaving the warehouse 40 will be described. The controller 44 sets the sterilization device 3 to a low-concentration ozone release mode, and causes the sterilization device 3 to release low-concentration ozone into the warehouse space 43 (arrow j). Alternatively, the controller 44 sets the sterilization device 3 to an internal sterilization mode, and causes the ozone generation process, internal sterilization process, and hydroxyl radical generation process to be performed.

Next, referring to FIG. 13, a method for sterilizing a refrigerated storage facility 50 (refrigerated container) using a sterilizer 3 will be described. A plurality of stored items 51 are stored in the refrigerated storage facility 50, and cold air is blown into the storage facility interior space 52 from an air supply duct 53 and exhausted from an exhaust duct 54. A plurality of sterilizers 3 are disposed inside the air supply duct 53 and the exhaust duct 54, respectively. Hereinafter, the sterilizer 3 disposed in the air supply duct 53 will be referred to as a first sterilizer 3A, and the sterilizer 3 disposed in the exhaust duct 54 will be referred to as a second sterilizer 3B.

The first sterilization device 3A is set to a high-concentration ozone release mode. The second sterilization device 3B is set to an ozone decomposition mode. The cold air (arrow l) supplied through the air supply duct 53 is taken into the first sterilization device 3A, which releases high-concentration ozone (arrow m) toward the storage space 52. The ozone released from the first sterilization device 3A sterilizes bacteria adhering to the walls and floor of the refrigerated storage 50 and airborne bacteria in the storage space 52. The gas (arrow n) exhausted from the storage space 52 to the exhaust duct 54 is taken into the second sterilization device 3B, which decomposes the remaining ozone and releases it (arrow o).

In this way, the sterilization method using the sterilization device 3 performs an ozone generation process, an ozone release process, and an external sterilization process in the first sterilization device 3A, and simultaneously performs an ozone decomposition process in the second sterilization device 3B, which is different from the first sterilization device 3A. This makes it possible to sterilize the inside of the refrigerated storage facility 50 with high-concentration ozone while suppressing the concentration of residual ozone in the gas exhausted from the exhaust duct 54. Note that the first sterilization device 3A does not necessarily have to be equipped with the hydroxyl radical generation unit 20, and the second sterilization device 3B does not necessarily have to be equipped with the ozone generation unit 10.

As described above, the sterilization device 3 that sterilizes outside air includes a fan unit 6 that takes in outside air, an ozone generation unit 10 that generates ozone, a hydroxyl radical generation unit 20 that generates hydroxyl radicals from ozone, and a control unit 7 that controls the ozone generation unit 10 and the hydroxyl radical generation unit 20. This allows the outside air to be sterilized flexibly using multiple modes.

To provide a sterilization device and sterilization method that can flexibly sterilize outside air.

1. 1A Automatic travel type sterilization device (sterilization device)
2 Automatic driving unit 3 Sterilizer 3A First sterilizer 3B Second sterilizer 6 Fan unit 7 Control unit 8 Intake port sensor (ozone sensor)
9. Exhaust outlet sensor (ozone sensor)
10 Ozone generating section 12 Vacuum ultraviolet ray irradiating section 20 Hydroxyl radical generating section 22 Near ultraviolet ray irradiating section

Claims (14)

A sterilization device for sterilizing outside air,
A fan section that takes in outside air,
An ozone generating unit that generates ozone;
a hydroxyl radical generating unit that generates hydroxyl radicals from ozone;
A control unit that controls the ozone generating unit and the hydroxyl radical generating unit;
A member for guiding the gas that has passed through the ozone generating section to the hydroxyl radical generating section;
Equipped with
The outside air taken in by the fan unit passes through the ozone generating unit and the hydroxyl radical generating unit in that order, and is then released to the outside . The sterilization device according to claim 1, wherein the ozone generating unit has a vacuum ultraviolet ray irradiation unit that irradiates vacuum ultraviolet rays. The sterilization device according to claim 1 or 2, wherein the hydroxyl radical generating unit has a near-ultraviolet ray irradiating unit that irradiates near-ultraviolet rays. The sterilization device according to claim 3, wherein the control unit controls the amount of near-ultraviolet light emitted by the near-ultraviolet light irradiation unit according to the concentration of ozone released to the outside. The sterilization device according to any one of claims 1 to 4, further comprising an ozone sensor that measures the ozone concentration. The sterilization device according to any one of claims 1 to 5, further comprising an automatic driving unit that moves on its own while measuring the surrounding environment. The sterilization device according to claim 6, comprising a plurality of the ozone generating units and a plurality of the hydroxyl radical generating units. A sterilization method using a sterilization device that sterilizes outside air,
The sterilization device is
An ozone generating unit that generates ozone;
a hydroxyl radical generating unit that generates hydroxyl radicals from ozone;
A member for guiding the gas that has passed through the ozone generating section to the hydroxyl radical generating section,
an ozone generating step of generating ozone from the outside air taken into the sterilization device in the ozone generating section ;
An ozone releasing step of releasing the generated ozone to the outside of the sterilization apparatus;
An external sterilization step of sterilizing the external space of the sterilization device with the ozone released to the outside;
an ozone decomposition step of generating hydroxyl radicals from the ozone remaining in the sterilized outside air taken in the sterilization device in the hydroxyl radical generating section , and decomposing the ozone. The sterilization device performs the ozone generation process, the ozone release process, and the external sterilization process while moving through the sterilization area,
The sterilization method according to claim 8, wherein the sterilization device then performs the ozonolysis step while moving through the area. The sterilization method according to claim 8, which executes the ozone generation process, the ozone release process, and the external sterilization process, and executes the ozone decomposition process after a predetermined time has elapsed. The ozone generating step, the ozone releasing step, and the external sterilization step are carried out in a first sterilization device;
9. The sterilization method according to claim 8, wherein the ozonolysis step is carried out simultaneously in a second sterilization device different from the first sterilization device. A sterilization method using a sterilization device that sterilizes outside air,
The sterilization device is
An ozone generating unit that generates ozone;
a hydroxyl radical generating unit that generates hydroxyl radicals from ozone;
A member for guiding the gas that has passed through the ozone generating section to the hydroxyl radical generating section,
an ozone generating step of generating ozone from the outside air taken into the sterilization device in the ozone generating section ;
An internal sterilization step of sterilizing the outside air with the ozone in the ozone generating unit ;
a hydroxyl radical generating step of generating hydroxyl radicals from the ozone remaining after sterilization in the hydroxyl radical generating section . The sterilization method according to claim 12, wherein in the hydroxyl radical generating step, the hydroxyl radicals are generated from the ozone and a predetermined concentration of ozone is left behind and released to the outside of the sterilization device. The sterilization method according to claim 12 or 13, in which the ozone generation process, the internal sterilization process, and the hydroxyl radical generation process are performed while the sterilization device moves through the sterilization area.

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