Air sterilization device

Abstract

[Problem] To satisfactorily disinfect air, as well as disinfect and deodorize items and equipment such as a chair, even in a large room. [Solution] When a door 120 of a booth 110 is closed and a switch 224 of an air disinfection unit 220 is switched on, a disinfection control unit 210 causes a UV lamp 130 to illuminate and drives a stirring fan 132 and a blower fan 140. Air is thereby taken into the booth 110 from the exterior and irradiated with UV light outputted from the UV lamp 130. At this time, air is stirred by the stirring fan 132, the UV light is irregularly reflected by the inside reflective surface of the booth 110, and air in the booth is efficiently disinfected. The disinfected air is delivered by a blower fan 140. The booth 110 is large, making it possible to disinfect the surface of equipment by the UV light if the equipment is placed therein.

Description

[Technical Field]

[0001] The present invention relates to an improvement in an air sterilization device that uses ultraviolet light. [Background technology]

[0002] A conventional sterilization device that uses ultraviolet light is, for example, the "ultraviolet sterilization device" described in Patent Document 1. This device is designed to prevent ultraviolet light from being emitted to the outside, and to prevent adverse effects on people and various components inside the room even when placed and used indoors. It is equipped with a sterilization chamber containing an ultraviolet lamp, an introduction section that introduces air into the sterilization chamber, a discharge section that discharges air from the sterilization chamber, and a fan that moves the air, and the ultraviolet light emitted by the ultraviolet lamp is obliquely directed toward the outside by a partition or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6903838 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the background art described above, the air introduced into the sterilization chamber is merely sterilized by the ultraviolet light emitted by the ultraviolet lamp, and even if this is released into the room, it does not effectively purify the air in the entire room. For example, with regard to the relationship between an ultraviolet sterilization device for air sterilization and wind speed, it is known that when the wind speed is high, the sterilization effect cannot be obtained even with ultraviolet light irradiation, and calculation results show that compared to a wind speed of 0 m / s (no wind), the sterilization effect is 80% at a wind speed of 2 m / s and 70% at a wind speed of 3.3 m / s (quoted from a paper by Hirofumi Shiraishi, "On Calculation of the Number of Germicidal Lamp Fixtures to be Installed for Air Sanitation Purposes" (Illuminating Engineering Institute of Japan)).

[0005] Additionally, in large facilities such as conference rooms, gymnasiums, and event halls, many chairs, tables, and other equipment are used, which must be disinfected, sterilized, and deodorized. It would be convenient if such equipment could be disinfected, sterilized, and deodorized efficiently.

[0006] The present invention has been made in light of the above points, and its object is to effectively purify the air even in a large room. Another object is to efficiently sterilize furniture such as chairs. [Means for solving the problem]

[0007] The present invention relates to an air sterilization device that sterilizes air by ultraviolet rays, and includes an ultraviolet ray emitting means that is installed in a booth and sterilizes the air in the booth by the ultraviolet rays, and an ultraviolet ray emitting means that ... sending out A blowing means for blowing air outside the booth sending out an ozone filter means for reducing the ozone contained in the air to be treated; Agitation means for agitating the air in the booth It is equipped with Furthermore, the booth is equipped with a space into which tools or equipment can be brought in to sterilize the tools or equipment with ultraviolet light, a door for bringing the tools or equipment into this space, and a control device that stops the emission of ultraviolet light when an open / close detection device provided on the door detects that the door is open. When sterilizing the tools or equipment, the control device controls so that the agitation device is not driven and the air blowing device is not driven or is driven at a low air volume. The above and other objects, features, and advantages of the present invention will become apparent from the following detailed description and accompanying drawings. [Effects of the Invention]

[0008] According to the present invention, the air inside the booth is sterilized and then released to the outside, thereby enabling the indoor space in which the booth is installed to be effectively purified, and in addition, tools can be brought into the booth and sterilized therein. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a diagram showing an embodiment of a booth portion of the air filtering apparatus of the present invention. [Figure 2] FIG. 2 is a diagram illustrating a configuration of a control device according to the embodiment. [Figure 3] FIG. 10 is a diagram showing the state during air sterilization in the embodiment. [Figure 4] FIG. 10 is a diagram showing the state during sterilization of the instrument in the embodiment. [Figure 5] FIG. 10 is a diagram showing another example of a booth. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, the mode for carrying out the present invention will be described in detail based on examples. [Example]

[0011] First, a first embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG. 1(A) shows an overview of an air sterilization apparatus 100 of this embodiment. Outdoor air is taken into a booth 110 through an intake port 112, sterilized using ultraviolet light within the booth 110, and then sent out of the booth 110 through an air outlet 114. The booth 110 is equipped with casters 116, allowing the entire apparatus to be moved. While the apparatus may be installed anywhere, a satisfactory cleaning effect can be achieved even when installed in a large space such as a gymnasium. A portion of the side of the booth 110 is provided with a transparent window 118 that blocks ultraviolet light but transmits visible light, allowing the interior to be seen. Furthermore, the interior of the booth 110 has a reflective or mirrored surface on the floor, walls, and ceiling, reflecting incident ultraviolet light. A stainless steel plate with a mirror-polished surface is used as the reflective surface.

[0012] 1(B) shows an example of the equipment configuration in the booth 110. In the figure, the booth 110 is provided with a door 120, which is provided with a locking mechanism 122 that keeps the door 120 in an open or closed state, and an open / close switch 124 that detects the open or closed state. The locking mechanism 122 is manually operated by an operator, and has the function of fixing the door 120 so that it does not open naturally when it is closed, and conversely, preventing the door 120 from closing naturally (not fixing) when it is open. The suction port 112 of the booth 110 is provided with an intake filter 126 that removes dirt, dust, and the like.

[0013] The booth 110 is equipped with an ultraviolet lamp 130 that emits ultraviolet light for sterilization, an agitation fan 132 that agitates the air inside the booth, and a forced stop switch 134 that forcibly stops operation. Furthermore, the air outlet 114 is equipped with a blower fan 140 that sends sterilized air to the outside, and an ozone filter 142 that removes ozone from the air. Activated carbon, for example, is used as the ozone filter 142. If necessary, the booth 110 can be designed to have a negative pressure to prevent ozone from leaking to the outside. These features help to keep the amount of ozone to around 0.01 to 0.02 ppm, which is not irritating to the human body.

[0014] In addition, parts such as the fan that are exposed inside the booth 110 are given a surface treatment such as painting to prevent deterioration due to ultraviolet rays. Also, light-blocking seals are provided in various places to prevent ultraviolet rays from leaking outside the booth 110. By providing the agitating fan 132, the ozone inside the booth can reach every detail. As will be described later, it is better to provide the agitating fan 132 in cases where a large number of folding chairs or the like are stacked inside the booth, but it may be omitted if unnecessary. Quiet models are used for the agitating fan 132 and the blower fan 140 to reduce noise.

[0015] 2 shows the control device 200 of the air filtering apparatus 100. The control device 200 is mainly composed of a filtering control unit 210, to which an air filtering unit 220 and an instrument filtering unit 230 are connected. The filtering control unit 210 is connected to the open / close switch 124 for the door 120, the ultraviolet lamp 130, the stirring fan 132, and the blower fan 140, and controls the operations of these units. The air filtering unit 220 is equipped with a time timer 222 and a switch 224 for starting its operation. The instrument filtering unit 230 is equipped with a second timer 232 and a switch 234 for starting its operation. The carbon dioxide concentration sensor 250 will be described later.

[0016] In conventional air sterilization devices (air purifiers) that use ultraviolet light, the time that air remains in the space irradiated with ultraviolet light is short, and sterilization is not necessarily effective. In contrast, the booth 110 of this embodiment has a large sterilization space that can accommodate tools or fixtures such as folding chairs. (1) As the ultraviolet lamp 130, a large sterilization lamp with high sterilization illumination can be installed. (2) A large number of ultraviolet lamps 130 can be installed, and the overall sterilization illumination intensity can be increased. (3) Since the air remains in the booth 110 for a longer period of time, the ultraviolet light is irradiated for a longer period of time, improving the sterilization effect. (4) The speed at which air stagnates and flows within the booth 110 is slowed down, so the sterilization effect is not weakened. There are advantages such as:

[0017] Next, the operation of this embodiment will be described with reference to Figures 3 and 4. First, the case where air sterilization is performed will be described. Figure 3 shows this process, in which air taken into the booth 110 is sterilized and then sent out. More specifically, the worker closes the door 120 and locks it with the locking mechanism 122. This causes the open / close switch 124 to turn "closed," which is detected by the sterilization control unit 210. In this state, when the worker turns "ON" the switch 224 of the air sterilization unit 220, the time timer 222 begins counting, and this is transmitted to the sterilization control unit 210. The sterilization control unit 210 turns on the ultraviolet lamp 130 and drives the stirring fan 132 and the blower fan 140.

[0018] As a result, air is taken into the booth 110 from outside, and ultraviolet light output from the ultraviolet lamp 130 is irradiated onto the air. At this time, the air is agitated by the agitation fan 132, and the ultraviolet light is diffused by the inner reflective surface of the booth 110. This allows the air inside the booth to be efficiently sterilized. In addition, a deodorizing effect can be expected from the ozone generated in the air. The sterilized air is sent out by the blower fan 140, and the ozone generated by the ultraviolet light irradiation is removed by the ozone filter 142.

[0019] Time timer 222 is set for, for example, 6 to 12 hours, so that sterilized air is blown out of the booth for a long period of time. If necessary, the amount of air blown out is adjusted by blower fan 140. In this way, sufficient air purification can be achieved even in large spaces such as school classrooms or gymnasiums.

[0020] Next, the case of instrument sterilization will be described. Figure 4 shows this situation, with instruments to be sterilized being carried into booth 110. Figure (A) shows the state as seen from the front, and Figure (B) shows the state as seen from above. In the example shown, folding chairs 300 are stacked and carried into booth 110. When the worker has finished carrying in the folding chairs 300, he closes door 120 and locks it with locking mechanism 122. This causes open / close switch 124 to turn "closed," which is detected by sterilization control unit 210.

[0021] In this state, when the operator turns on the switch 234 of the instrument sterilization section 230, the second timer 232 starts counting, and this is notified to the sterilization control section 210. The sterilization control section 210 turns on the ultraviolet lamp 130. The stirring fan 132 is not driven, and the blower fan 140 is not driven or is driven at a low airflow rate. As a result, the air flow within the booth 110 is at the level of natural ventilation or is very low.

[0022] The ultraviolet rays output from the ultraviolet lamps 130 are irradiated not only onto the air inside the booth, but also onto the surface of the folding chair 300. The ultraviolet rays are also diffused by the inner reflective surface of the booth 110, and reach the surface of the folding chair 300 that is not facing the ultraviolet lamps 130. This ensures that the surface of the folding chair 300 is effectively disinfected. Since ultraviolet rays are also irradiated onto the air inside the booth, ozone is generated, and the ozone can be expected to have disinfecting and deodorizing effects. As with the above embodiment, the ozone is removed by the ozone filter 142 when the air is released to the outside.

[0023] The second timer 232 is set to, for example, about 10 to 180 seconds. According to this example, the booth 110 is installed in, for example, a school classroom or gymnasium, and the surfaces of equipment or fixtures such as folding chairs 300 used in the classroom can be efficiently disinfected. For example, chairs and the like are sometimes disinfected with alcohol after a meeting, but according to this example, they can be easily disinfected by simply bringing them into the booth 110 and irradiating them with ultraviolet light.

[0024] 3 or 4, if a worker is left behind in the booth, he or she can operate the forced stop switch 134, which will cause the sterilization control unit 210 to stop the ultraviolet lamp 130 from emitting light. This prevents people from being trapped inside the booth and being harmed by ultraviolet rays and ozone. The door 120 may be designed to be able to be opened from the inside.

[0025] As described above, according to this embodiment, ultraviolet light is irradiated into a large-volume booth, and the air flow rate in the sterilization space is slowed down, allowing for sufficient sterilization time, and large-volume air sterilization, surface sterilization of tools and fixtures, and deodorization using ozone can be performed all in one device. Furthermore, air purification can be performed in large rooms such as gymnasiums, conference rooms, various public facilities, and event halls.

[0026] <Prototype Example> Next, a prototype device related to the present invention will be described. (1) In this prototype, the ultraviolet lamp uses a wavelength of 253.7 nm, which has a high sterilizing power. The sterilizing effect of ultraviolet light is measured by the sterilizing dose (J / m 2 ) and the sterilization dose (J / m 2 )=sterilization radiation intensity (W / m 2 ) × irradiation time (sec). That is, the sterilization ray irradiance (W / m 2 The sterilization effect can be increased by increasing the UV intensity or the irradiation time (sec). Existing air purifiers are small, so the irradiation (sterilization) time is short, and the air is discharged without achieving sufficient sterilization effect. However, this device has a large irradiation (sterilization) booth, which increases the amount of ultraviolet light and the irradiation time, thereby increasing the sterilization dose and making it possible to sterilize large volumes of air.

[0027] The dimensions of this prototype compared with a conventional model are shown in Figures 1(A) and 1(C). As shown in Figure 1(A), the size of the path in this prototype, through which air is drawn into booth 110 from air inlet 112 and then blown out through air outlet 114, is 1200 mm wide and 1500 mm long. In contrast, commercially available air purifiers have a very narrow path of 300 mm wide and 600 mm long, as shown in Figure 1(C). In this way, by enlarging sterilization booth 110, where ultraviolet rays are irradiated, the air retention time is increased, and the internal cross section is approximately 10 times larger, which reduces the air velocity to approximately 1 / 10, thereby minimizing the reduction in sterilization effectiveness due to high air velocity.

[0028] In classrooms, event halls, and other locations, air sterilization is used to purify the air while people are inside. However, by placing large items such as used folding chairs, transparent partitions for infection prevention, and desk furniture in the prototype sterilization booth after people leave the room, bacteria and viruses adhering to these surfaces can be quickly sterilized with ultraviolet light, and further disinfected and deodorized with ozone, eliminating the need for manual labor such as cleaning furniture with alcohol. Ozone also improves the inactivation of bacteria. The ozone filter 142 significantly reduces the amount of harmful ozone that leaks outside, ensuring safety.

[0029] Next, we will show an example calculation comparing the sterilization capabilities of this prototype machine with commercially available machines. Because it is not possible to derive practical figures from data on commercially available ultraviolet air sterilization devices, we performed a simple calculation using the "temporal change in airborne bacterial concentration (bacterial concentration CT after T hours)" formula from Panasonic Corporation, the manufacturer of ultraviolet sterilization lamps, which calculates the practical number of units to install when sterilizing air, by changing only the ultraviolet intensity and irradiation time, which are key to sterilization power, while keeping all other conditions the same. a, Indoor volume to be cleaned: 1,536 m 3 (W24m x L16m x H4m) (approximately 233 tatami mats) b. For comparison, Iwasaki Electric Co., Ltd.'s "Airia Power" (for 200 tatami mats) was used. c) Measure the time it takes to reach a 10% sterilization concentration (90% reduction rate)

[0030] As a result, the results shown in Table 1 below were obtained. [Table 1]

[0031] For the comparison machine, the values ​​are extracted from the catalog data or estimated values ​​are included. For the test data published in the catalog of the prototype machine, 3 There is only graph data from the test chamber, and no practical data for 200 tatami mats or 400 tatami mats is listed. The estimated number of units to be installed is 1,680 m. 3 (approximately 400 tatami mats) for 120 minutes, but one circulation (1,680 m 3 ÷14m 3 / min = 120 minutes), and there is no indication of the basis for the sterilization time (sterilization effect). 3 Strong wind (14m 3 / min), which is a 90% reduction rate, for 10 minutes, resulting in 5.6 cycles, or 1,680 m 3 In this case, the time required is 120 minutes x 5.6 times = 672 minutes = 11.2 hours (h), but since this is an estimated value in a test chamber with good conditions, it is expected that in practice the efficiency will be even worse.

[0032] The results of this calculation are for reference only, but the ultraviolet intensity of the ultraviolet lamp of this prototype is 2.3 times higher, the irradiation time is 12.2 times higher, and the sterilization dose (J / m) is 1.2 times higher than that of the comparison machine. 2 ) is approximately 28 times stronger, so it can disinfect in 1 / 28 of the time.

[0033] A reference calculation formula is provided based on Panasonic Corporation's calculation data for the number of sterilization lamps to be installed. The change in airborne bacterial concentration over time (bacterial concentration CT after T hours) can be calculated using the following formula. CT=C0e (-aT / R) a=εnV e: base of natural logarithm (e≒2.72) CT: Bacterial concentration after T hours (m -3 ) C0: Initial bacterial concentration (m -3 ) T: Time (h) R: Room volume (k) ε: Sterilization rate of sterilized air = 82.0% n: number of units V: Circulating air volume of the sterilization device (k / h) = 25m 3 / h The above formula is based on ideal conditions, where there is no bacterial growth or natural death, and no air inflow or outflow.

[0034] Other Embodiments The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit and scope of the present invention. For example, the following modifications are also included.

[0035] (1) The shapes, dimensions, and materials shown in the above embodiments are merely examples and may be modified as needed. For example, as shown in the front and plan views of FIG. 5(A), booth 110A may be life-size and used to store clothes 310 and other items for sterilization. Alternatively, as shown in the front and plan views of FIG. 5(B), a shelf 320 may be provided within booth 110B to store various tools 322. The shelf 320 may have a reflective surface that reflects ultraviolet light, allowing for efficient sterilization.

[0036] (2) A plurality of the above-mentioned doors 120, suction ports 112, air outlets 114, ultraviolet lamps 130, stirring fans 132, etc. may be provided as needed. When a plurality of suction ports 112 are provided, each of them should also be provided with an intake filter 126, and when a plurality of air outlets 114 are provided, each of them should also be provided with an air blower fan 140 and an ozone filter 142.

[0037] (3) The size of the booth 110 is preferably large enough for a worker to enter or tall enough to facilitate the loading and unloading of tools, but may be of any appropriate size.

[0038] (4) During the air sterilization operation shown in Fig. 3, if chairs or other equipment are placed inside the booth 110, the equipment can also be sterilized at the same time. In other words, cleaning of the indoor space and sterilization of the equipment can be performed simultaneously.

[0039] (5) The sterilization of the air in the booth by the ultraviolet lamp 130 may be performed in a state where the air remains stagnant in the booth by, for example, stopping the air blown by the blower fan 140 using the sterilization control unit 210. For example, a. The airflow is stopped for a certain period of time (for example, a few minutes), or the amount of airflow is reduced to perform sterilization, and then the airflow is restarted for a certain period of time, and this operation is repeated (intermittent operation). b) While the airflow is stopped or reduced, the stirring fan 132 stirs the air. In this way, even if the booth 110 has a large capacity, the air can be sufficiently sterilized.

[0040] (6) In addition to the above-described embodiments, a carbon dioxide concentration sensor 250 may be provided as shown in Figures 1 and 2. For example, the carbon dioxide concentration in a room such as a conference room in which the air filtering apparatus 100 of this embodiment is installed is measured by the carbon dioxide concentration sensor 250. If the carbon dioxide concentration reaches a certain level or higher, it can be assumed that the conference room is crowded with people and is not sufficiently ventilated. Therefore, the sterilization control unit 210 operates the air filtering apparatus 100 of this embodiment to sterilize the air in the conference room.

[0041] (7) In the above embodiment, the air outside the booth is sterilized and then released outside the booth, but it is also possible to take in outdoor air, sterilize it, and release it into a conference room, etc. In this case, the amount of outdoor air and indoor air taken in can be adjusted, and for example, when the carbon dioxide concentration exceeds a certain level, the amount of outdoor air taken in can be increased. (8) In the present invention, "sterilization" also includes "disinfection" and "sterilization." [Industrial Applicability]

[0042] According to the present invention, the air inside the booth is sterilized and then released to the outside, thereby enabling the indoor space in which the booth is installed to be effectively purified. In addition, instruments can be brought into the booth and sterilized therein, making the present invention suitable for cleaning indoor spaces used by many people and sterilizing instruments. [Explanation of symbols]

[0043] 100: Air sterilization device 110, 110A, 110B: Booth 112: Suction port 114: Ventilation vent 116: Caster 118: Transparent window 120: Door 122: Locking mechanism 124: Open / close switch 126: Intake filter 130: Ultraviolet lamp 132: Stirring fan 134: Forced stop switch 140: Blower fan 142: Ozone filter 200: Control device 210: Sterilization control unit 220: Air sterilization unit 222: Time timer 224: Switch 230: Instrument sterilization section 232: Second timer 234: Switch 250: Carbon dioxide concentration sensor 300: Chair 310:Clothing 320: Shelf 322: Equipment

Claims

1. An air sterilization device that sterilizes air using ultraviolet rays, an ultraviolet light emitting means installed in the booth for sterilizing the air in the booth with the ultraviolet light; a blowing means for blowing the air in the booth to the outside of the booth; an ozone filter means for reducing the ozone contained in the air discharged outside the booth; agitation means for agitating the air in the booth; It is equipped with Furthermore, in order to sterilize equipment and fixtures using ultraviolet light, A space in which tools or equipment can be brought into the booth, A door for bringing equipment or fixtures into this space, a control device that stops the emission of ultraviolet light when the door is detected to be open by an open / close detection means provided on the door; It is equipped with When sterilizing the tools or fixtures, the control device controls the agitation means not to be driven and the air blowing means not to be driven or to be driven at a low air volume.

2. 2. The air filtering apparatus according to claim 1, wherein a reflective surface that reflects the ultraviolet light is provided on at least a part of the inside of the booth.

3. 2. The air filtering apparatus according to claim 1, wherein the booth has a space for a worker to carry in the tools or equipment.

4. an air sterilization unit that counts the time when sterilizing the air in the booth using a time timer; An instrument sterilization unit that counts the time when sterilizing instruments or fixtures in the booth using a second timer; 4. The air filtering device according to claim 1, further comprising:

5. 5. The air filtering device according to claim 1, further comprising a control means for causing air to remain in the booth and filtering the air using the ultraviolet light emitting means.

6. An air sterilization device as described in Claim 5, characterized in that the air path from the air suction port in the booth to the blowing means is enlarged, thereby lengthening the air retention time and slowing down the wind speed.

7. The air filtering device according to any one of claims 1 to 6, further comprising a control means for providing a carbon dioxide concentration sensor outside the booth, and filtering the air and releasing it outside the booth when the carbon dioxide concentration sensor detects that the carbon dioxide concentration outside the booth is equal to or greater than a set value.

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