Plasma treatment device for storage box

Abstract

To provide a plasma treatment device for a storage box enabling reduction of bacteria within the storage box.SOLUTION: A plasma treatment device for a storage box comprises: a plasma generation section 10 including at least a dielectric layer and a pair of electrode layers disposed on both sides of the dielectric layer to generate plasma; a power supply section 30 for applying an alternating voltage to the pair of electrode layers; and a gas flow section 20 configured to flow gas into the plasma generation section 10 to treat the gas with plasma and to supply the plasma-treated gas into a storage box 200.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a plasma processing apparatus for a storage box. [Background technology]

[0002] In recent years, a technique called dielectric barrier discharge (DBD) has been developed in plasma processing technology, making it possible to generate low-temperature plasma at atmospheric pressure. As a result, the range of applications of plasma processing has expanded, and it is increasingly being used in a variety of applications. The purposes of plasma processing include sterilization, deodorization, surface modification, and decomposition of chemical substances. Furthermore, the substances that can be subjected to plasma processing can be solid, liquid, or gaseous.

[0003] Various plasma processing apparatuses have been developed to perform continuous plasma processing while flowing air. For example, Patent Document 1 discloses a plasma generating apparatus in which plasma generating units, each having a flat plate-shaped first electrode and a second electrode facing each other across a gap, are stacked in two or more layers. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-190472 Summary of the Invention [Problem to be solved by the invention]

[0005] For example, the inside of storage boxes such as shoe boxes, geta boxes, and lockers for storing items is a closed space where bacteria can easily grow, and therefore it is desirable to reduce the bacteria inside the storage boxes.

[0006] In view of the above background, an object of the present invention is to provide a plasma processing apparatus for a storage box that can reduce bacteria inside the storage box. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention is characterized by comprising a plasma generation unit that generates plasma and that has at least a dielectric layer and a pair of electrode layers provided on both sides of the dielectric layer, a power supply unit that applies an AC voltage to the pair of electrode layers, and a gas flow unit that flows a gas through the plasma generation unit to treat the gas with plasma and supplies the gas treated by plasma into a storage box.

[0008] According to the present invention, a gas treated with plasma (also called a plasma gas) can be generated and supplied into the storage box, thereby reducing bacteria in the storage box.

[0009] It is also preferable to have a sensor that detects plasma in the storage box, and a control unit that receives the detection result of the sensor and sends a signal to apply an AC voltage to the power supply unit based on the detection result.

[0010] According to the present invention, it is possible to estimate the amount of plasma-treated activated species, thereby enabling the device to operate efficiently and stably supply plasma-treated gas.

[0011] It is also preferable that the power supply unit has a control unit that transmits a signal to apply an AC voltage to the power supply unit based on a timer unit that measures time.

[0012] According to the present invention, the timing of generating plasma can be controlled according to the time, thereby making it possible to supply plasma gas efficiently.

[0013] It is also preferable that the plasma generating device has a wireless interface that provides information to a terminal device and a control unit that transmits a signal to apply an AC voltage to the power supply unit, and that the control unit transmits information regarding plasma generation to the outside via the wireless interface.

[0014] According to the present invention, for example, a user can obtain information regarding plasma generation.

[0015] It is also preferable that the plasma generating unit has a housing that covers the plasma generating unit and is divided into multiple spaces by the dielectric layer, and that the housing has an inlet section through which gas flows into each space and an outlet section through which gas flows out, and that the housing is configured so that gases of different pressures flow into each space.

[0016] According to the present invention, gas treated by a plurality of plasmas with different pressures can be supplied from a single plasma generating unit, i.e., gas treated by plasmas with different pressures can be supplied according to the load of the supply destination. [Effects of the Invention]

[0017] The plasma processing device for a storage box of the present invention can reduce bacteria, viruses, and mold inside the storage box. Furthermore, gas treated with the leaked plasma can reduce bacteria, viruses, and mold in the surrounding environment. Furthermore, odorous components leaking from the storage box and chemical substances emitted from the storage box can be absorbed into the plasma generating unit and converted into other substances, making them harmless. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 2 is a perspective view for explaining a plasma generating unit. [Figure 2] FIG. 2 is a perspective view for explaining a plasma generating unit. [Figure 3] FIG. 2 is a cross-sectional view illustrating a plasma generating unit. [Figure 4] FIG. 10 is a perspective view for explaining a plasma generating unit according to a first modified example. [Figure 5] FIG. 10 is a perspective view for explaining a plasma generating unit according to a second modified example. [Figure 6] FIG. 10 is a perspective view for explaining a plasma generating unit according to a third modified example. [Figure 7]FIG. 10 is a cross-sectional view for explaining a plasma generating unit according to a fourth example. [Figure 8] FIG. 10 is a cross-sectional view for explaining a plasma generating unit according to a fifth example. [Figure 9] FIG. 10 is a cross-sectional view for explaining a plasma generating unit according to a sixth example. [Figure 10] 1 is a perspective view showing a plasma processing apparatus for a storage box according to a first embodiment of the present invention; [Figure 11] 1 is a block diagram showing a plasma processing apparatus for a storage box according to a first embodiment; [Figure 12] 1 is an enlarged side view showing a plasma processing apparatus according to a first embodiment. [Figure 13] FIG. 10 is a perspective view showing a plasma processing apparatus for a storage box according to a second embodiment of the present invention. [Figure 14] FIG. 10 is a side view showing a plasma processing apparatus according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, embodiments of the present invention will be described in detail, but the embodiments of the present invention are not limited to the embodiments described below. Each embodiment and modified example can be applied in appropriate combination. Furthermore, directions such as "upper" and "lower" in the description are used for convenience of explanation and do not limit the directions of the present invention.

[0020] The plasma processing apparatus for a storage box of this embodiment has a multilayered plasma generating unit having a dielectric layer, an electrode layer, and a mask layer (optional) for continuous plasma processing of gas, a power supply unit capable of applying an AC voltage between the pair of electrode layers, and a gas flow unit capable of flowing gas through the plasma generating unit. In dielectric barrier discharge, a dielectric layer is provided between two electrode layers, and by applying an AC voltage between the two electrode layers, plasma can be generated within the dielectric layer sandwiched between the two electrode layers. First, the plasma generating unit will be described.

[0021] <Basic structure of the plasma generation unit> As shown in Figures 1 and 2, the plasma generating unit 10 includes a dielectric layer 11, an upper electrode 12, a lower electrode 13, an upper mask layer 14, and a lower mask layer 15. The plasma generating unit 10 is a flexible thin-film member. For convenience, the dielectric layer 11 is expressed as a single dielectric, but it may also be a laminate of one or more dielectrics containing air. The mask layer is provided to protect the electrodes and improve the assembly and performance of the electrodes, and may be omitted. Furthermore, by appropriately selecting the thickness and position of the mask layer, excessive electric field concentration on the electrodes can be prevented, thereby extending the life of the electrodes.

[0022] As shown in Figures 1 to 3, the dielectric layer 11 is a layered member disposed between the upper electrode 12 and the lower electrode 13. The material of the dielectric layer 11 is an insulating material with a large breakdown voltage so as to prevent discharge between the upper electrode 12 and the lower electrode 13. Furthermore, since the material of the dielectric layer 11 is exposed to the generated plasma, it is preferable that the material be durable against the active substances generated in the plasma. The material of the dielectric layer 11 is preferably a material selected from the group consisting of glass, ceramics, and synthetic resins. "Mainly" means that the component composition is 50% by mass or more (the same applies hereinafter). For convenience, the dielectric layer 11 is shown as a single dielectric, but it may also be a layered structure of multiple dielectrics including air.

[0023] Examples of glass include soda-lime glass (soda glass), borosilicate glass, quartz glass, lead glass, and oxide glass. Synthetic resins include thermoplastic resins and thermosetting resins. Examples of thermoplastic resins include general-purpose resins such as polyolefin, polystyrene, polyvinyl acetate, polyurethane, polylactic acid, ABS resin, AS resin, acrylic resin, polyvinyl chloride, and polyvinylidene chloride; engineering plastics such as polyamide, polyacetal, polycarbonate, modified polyphenylene ether, polyester, and cyclic polyolefin; polyphenylene sulfide, polysulfone, polyethersulfone, polyarylate, liquid crystal polymer, polyetheretherketone, polyimide, polyamideimide, polyetherimide, fluorine-based resin, unsaturated polyester resin, and polyurethane resin. Among these synthetic resins, silicone-based resins, polyimide-based resins, and Teflon®-based resins, which have excellent durability, are particularly preferred. The thickness of the dielectric layer 11 is not particularly limited, but is preferably 0.1 mm to 5.0 mm, more preferably 0.1 mm to 3.0 mm, and even more preferably 0.1 mm to 1.0 mm, in order to achieve lightweight and compactness.

[0024] As shown in FIGS. 2 and 3, the upper electrode (electrode layer) 12 and the lower electrode (electrode layer) 13 are layer members disposed on the front and back of the dielectric layer 11. The upper electrode 12 and the lower electrode 13 are each provided with a through-hole 16 penetrating in the thickness direction. In this embodiment, the through-holes 16 are oval in shape, and five through-holes 16 are formed, but the shape and number are not limited. The through-holes 16 may be omitted, but the presence of the through-holes 16 in this embodiment makes it easier to generate plasma and facilitates the creation of a power supply circuit. Furthermore, contact with gas at the through-holes 16 enables plasma processing of the gas.

[0025] The upper electrode (electrode layer) 12 and the lower electrode (electrode layer) 13 are formed of a conductive material, and may be a metal plate (including metal foil), a conductive paint, a conductive polymer, a conductive film, etc. The thickness of the upper electrode 12 and the lower electrode 13 is not particularly limited, but is preferably 5 μm to 1.0 mm, more preferably 5 μm to 0.2 mm, and even more preferably 5 μm to 0.1 mm, respectively, in order to provide a flexible, lightweight, and compact processing device.

[0026] The dielectric layer 11, the upper electrode 12, and the lower electrode 13 may be laminated without using an adhesive, or may be bonded with an adhesive. The adhesive is preferably a material that is durable against active substances generated in plasma. Examples of adhesives include epoxy, acrylic, urethane, phenol, urea, silicone, cyanoacrylate, rubber, and vinyl acetate adhesives. Among these, silicone adhesives and UV-curable epoxy adhesives are preferred from the viewpoint of durability, with polyamide adhesives, polyimide adhesives, and silicone adhesives being more preferred. The thickness of the adhesive is preferably 0.01 to 0.2 mm, and more preferably 0.01 to 0.1 mm.

[0027] As shown in FIG. 3 , the upper mask layer (mask layer) 14 and the lower mask layer (mask layer) 15 are members respectively disposed on the outer sides of the upper electrode 12 and the lower electrode 13. More specifically, the upper mask layer 14 is disposed on the upper surface of the upper electrode 12. The lower mask layer 15 is disposed on the lower surface of the lower electrode 13. The upper mask layer 14 and the lower mask layer 15 are each provided with through holes 17. In this embodiment, the through holes 17 are oval and five of them are formed, but the shape and number are not limited thereto. The through holes 17 may be omitted, but for ease of manufacture, it is preferable that the through holes 17 are the same as the through holes 16, although this is not limited thereto.

[0028] 2 and 3, through-hole 17 has the same shape as through-hole 16 and is connected to each other. Through-holes 16 and 17, dielectric layer 11 is exposed to the outside. In other words, the surface of dielectric layer 11 is exposed to the outside at multiple locations where through-holes 16 and 17 are formed. Hole walls (cross-sectional portions) 16a and 17a of through-holes 16 and 17 are also exposed to the outside.

[0029] The upper mask layer 14 and the lower mask layer 15 are formed of an insulating material. The hardness of the upper mask layer 14 and the lower mask layer 15 is preferably equal to or less than that of the upper electrode 12 and the lower electrode 13. Although the plasma generation unit 10 can be difficult to handle if it is manufactured using a thin material, providing the upper mask layer 14 and the lower mask layer 15 improves ease of handling. Furthermore, the upper mask layer 14 and the lower mask layer 15 protect the thin conductor from mechanical and physical shocks during manufacturing and use, as well as deterioration caused by the surrounding environment. They also provide mechanical protection from scratches that may occur during manufacturing. Considering that the plasma generation unit 10 will be installed on an object to be attached, the upper mask layer 14 and the lower mask layer 15 preferably have a hardness that allows for easy installation along the object and also improves ease of handling. Furthermore, dividing the dielectric layer 11 into two allows the upper and lower structures of the plasma generation unit 10 to be symmetrical. It can be easily manufactured by assembling the upper and lower layers and bonding them together in the center. In this case, the dielectric layer 11 is divided into three layers: the upper layer, the lower layer, and the adhesive layer, but can be considered electrically as a single dielectric. The thicknesses of the upper mask layer 14 and the lower mask layer 15 are not particularly limited, but in order to provide a flexible, lightweight, and compact processing device, they are preferably 5 μm to 1.0 mm, more preferably 5 μm to 0.2 mm, and even more preferably 5 μm to 0.1 mm. The thicknesses of the upper mask layer 14 and the lower mask layer 15 may be set as appropriate, but in this embodiment they are formed to be larger than the thicknesses of the upper-layer electrode 12 and the lower-layer electrode 13.

[0030] The plasma generating unit 10 is very thin and flexible, which can make it difficult to handle during assembly. Furthermore, the upper electrode 12 and the lower electrode 13 are formed of conductive materials, such as conductive metals or conductive dielectrics. Metals, for example, can be corroded by liquids or gases. For example, the upper electrode 12 and the lower electrode 13 are oxidized by highly oxidizing gases and corroded by sulfuric acid or hydrochloric acid. Furthermore, if the upper electrode 12 and the lower electrode 13 are made of a resin-based conductive material, they may be deteriorated by humidity or acid. Furthermore, the plasma generating unit 10 is designed to be installed according to the shape of the object to which it is to be attached. However, if only the upper electrode 12 and the lower electrode 13 are used without the upper mask layer 14 and the lower mask layer 15, problems can arise, such as wrinkles in the metal constituting the electrodes or gaps between the electrodes and the dielectric layer 11, if the electrodes are made of thin metal. If gaps are formed between the upper layer electrode 12 and the lower layer electrode 13 and the dielectric layer 11, this can cause abnormal discharge or partial discharge. In this regard, according to this embodiment, the upper mask layer 14 and the lower mask layer 15 can protect the upper electrode 12 and the lower electrode 13, and the plasma generating unit 10 can be easily handled, improving workability and assembly. Furthermore, the provision of the upper mask layer 14 and the lower mask layer 15 allows installation on an object without forming wrinkles or gaps. Furthermore, when multiple pairs of electrodes are provided to form a multi-stage structure, the upper mask layer 14 and the lower mask layer 15 also serve as part of the dielectric that constitutes the barrier discharge, making it less likely that abnormal discharge will occur even if gaps are formed during installation. Depending on the situation, the same effect can be achieved with either the upper or lower mask layer.

[0031] The outer edges of upper-layer electrode 12 and lower-layer electrode 13 may be sealed with an insulator (not shown) to prevent deterioration over time due to exposure to the outside world and to prevent discharge from occurring via the outer edges other than through-hole 16. When a resin or the like is used as the mask layer, this effect is achieved because the resin thinly spreads over not only upper-layer electrode 12 and lower-layer electrode 13 but also the upper and lower surfaces of dielectric layer 11. Similarly, the outer edges of the upper mask layer 14 and the lower mask layer 15 may be sealed with an insulator (not shown) to prevent their outer edges from being exposed to the outside world and reacting with external substances to deteriorate over time, and to prevent discharge from occurring through the outer edges other than the through holes 17.

[0032] When the longitudinal direction of the through holes 16, 17 is parallel to the gas flow direction, the resistance to the gas flow is small and the gas flows smoothly. On the other hand, when the longitudinal direction of the through holes 16, 17 is perpendicular to the gas flow direction, the resistance to the gas flow is large, the gas flow is disturbed, and the gas is agitated.

[0033] The shape, number, and orientation of the through-holes 16 and 17 relative to the gas flow can be selected appropriately depending on the purpose of the plasma processing, the effect of the plasma processing, and other factors. The through-holes may have different shapes on the front and back sides of the plasma generating unit 10. Alternatively, through-holes may be provided on the front side of the plasma generating unit 10, while no through-holes are provided on the back side. In this example, the through-holes are shown as excessively rounded rectangles, but this shape is not required. Circles, ellipses, squares, triangles, and other shapes are also acceptable. However, shapes with sharp corners tend to concentrate the electric field, so rounded corners are more appropriate. A similar effect can also be achieved with a structure with larger holes, such as a mesh-like shape. While five holes are shown in the figure, there is no limit to the number. Multiple holes may be arranged vertically or horizontally. Furthermore, a company logo or initials may be displayed on the plasma area, allowing it to be used as a display.

[0034] <First Modification of Plasma Generation Unit> 4 is a perspective view for explaining a plasma generating unit according to a first modified example. The plasma generating unit 10A according to the first modified example differs from the basic structure described above in that it does not have an upper mask layer 14. As in the plasma generating unit according to the first modified example, the mask layer may be provided only on one side of the plasma generating unit 10A.

[0035] <Second Modification of Plasma Generation Unit> FIG. 5 is a perspective view illustrating a plasma generating unit according to a second modified example. The plasma generating unit 10B according to the second modified example differs from the basic structure described above in that it does not include the upper mask layer 14 and the lower mask layer 15. The upper mask layer 14 and the lower mask layer 15 may be omitted, as in the plasma generating unit 10B according to the second modified example. That is, by configuring the plasma generating unit 10B with a dielectric layer 11, an upper-layer electrode 12, and a lower-layer electrode 13, it is possible to further reduce the size and the number of parts. Furthermore, when using this electrode in a process for manufacturing printed circuit boards, semiconductors, etc., a process step can be omitted, thereby reducing the cost of the product.

[0036] Furthermore, as in the first and second modified examples, by omitting either or both of the upper mask layer 14 and the lower mask layer 15, the overall thickness can be reduced and flexibility can be increased, which is convenient when creating an ultra-compact plasma generation device.

[0037] <Third Modification of Plasma Generation Unit> FIG. 6 is a perspective view illustrating a plasma generation unit according to a third modified example. The plasma generation unit 10C according to the third modified example differs from the basic structure described above in that an air layer 18C is provided below the dielectric layer 11C. However, if air is considered a dielectric with a relative dielectric constant of 1 and the combined air and dielectric layer 11C are considered a single dielectric, the plasma generation unit 10C can be considered the same as the basic structure shown in FIG. 2. The composite relative dielectric constant (or dielectric constant) can be calculated from the respective relative dielectric constants (or dielectric constants) and thicknesses. The plasma generation unit 10C according to the third modified example includes a dielectric layer 11C, an upper electrode 12, a lower electrode 13, an upper mask layer 14, a lower mask layer 15, and an air layer 18. The air layer 18 is provided between the dielectric layer 11C and the lower electrode 13. In the third modified example, three surfaces can come into contact with gas: the air layer 18 between the upper electrode 12 and the lower electrode 13, the back surface of the lower electrode 13, and the back surface of the upper electrode 12. The back surface here refers to the surface opposite to the air layer 18. This improves the plasma utilization efficiency compared to when only the air layer 18 is used, and allows for plasma processing of a larger amount of gas.

[0038] <Fourth Modification of Plasma Generation Unit> FIG. 7 is a cross-sectional view illustrating a plasma generation unit according to a fourth modification. The plasma generation unit 10D according to the fourth modification differs from the third modification in that it does not include an upper mask layer 14. In this case, too, a dielectric with a relative permittivity of 1 is considered. Furthermore, if the dielectric layer 11C and the dielectric layer 11C are considered as a single dielectric, the composite dielectric portion in this structure can be considered to be the same as the dielectric shown in FIG. 2 for the basic structure. The composite relative permittivity (or dielectric constant) can be calculated from the thickness and dielectric constant of the dielectric layer 11C and the thickness and dielectric constant of the air layer 18 (or the dielectric constant of air if air is permeable). The plasma generation unit 10D includes the dielectric layer 11C, the upper electrode 12, the lower electrode 13, the lower mask layer 15, and the air layer 18. As in the fourth modification, the upper mask layer may be omitted while providing the air layer 18 between the dielectric layer 11C and the lower electrode 13. This configuration can achieve substantially the same effects as the third modification while reducing the number of components. Furthermore, when the electrodes are produced using the processes for printed circuit boards or semiconductor ICs, the process steps can be omitted, thereby reducing costs.

[0039] <Fifth Modification of Plasma Generation Unit> FIG. 8 is a cross-sectional view illustrating a plasma generating unit according to a fifth modification. The plasma generating unit 10E according to the fifth modification differs from the third modification in that it does not include the upper mask layer 14 and the lower mask layer 15. The plasma generating unit 10E also includes a dielectric layer 11Cb on the lower surface of the lower electrode 13. The plasma generating unit 10E includes dielectric layers 11Ca and 11Cb, an upper electrode 12, and a lower electrode 13. The dielectric layer 11Cb on the lower surface of the lower electrode 13 is used to support the lower electrode 13. As in the fifth modification, the upper and lower mask layers may be omitted while providing an air layer 18 between the dielectric layer 11Ca and the lower electrode 13. This configuration achieves substantially the same effects as the third modification while reducing the number of components. This reduces the thickness of the electrode. Furthermore, when fabricating this electrode using a printed circuit board or semiconductor IC process, this eliminates a process step, thereby reducing costs. Furthermore, the reduced material thickness improves flexibility.

[0040] The upper dielectric layer 11Ca and the air layer 18 function as a single dielectric. This dielectric constant can be calculated from the relative permittivity (or dielectric constant) and thickness of the upper dielectric layer 11Ca, and, if air is used as the gas, the relative permittivity (or dielectric constant) of the air and the thickness of the air layer 18. The lower dielectric layer 11Cb plays almost no role in plasma generation. However, this structure allows the same material to be used for the upper electrode 12 and the lower electrode 13. This reduces manufacturing costs.

[0041] <Sixth Modification of Plasma Generation Unit> 9 is a cross-sectional view for explaining a plasma generating unit according to the sixth modified example. The plasma generating unit 10F according to the sixth modified example includes, from top to bottom, an air layer 18, an upper electrode 12, a dielectric layer 11Ca, an air layer 18, a lower electrode 13, a dielectric layer 11Cb, an air layer 18, an upper electrode 12, a dielectric layer 11Ca, an air layer 18, a lower electrode 13, and a dielectric layer 11Cb. In other words, it is configured by stacking two plasma generating units 10E according to the fifth modified example in the height direction. The ends of the dielectric layers 11Ca and 11Cb are supported by a box-shaped housing 21F.

[0042] Inside the housing 21F, basic units in which an upper-layer electrode 12 is laminated only on one side (top surface) of a dielectric layer 11Ca and basic units in which a lower-layer electrode 13 is laminated only on one side (top surface) of a dielectric layer 11Cb are alternately arranged with an air layer (gas inlet layer) 18 between them. As a result, electrodes of opposite polarity are alternately laminated, but if a space in which plasma is not generated is desired, the electrodes do not need to be alternately arranged. By designing a space in which plasma is not generated in this way, it is possible to place a sensor, wiring, or other circuits between them. An air layer 18 is formed between each of the electrode layers adjacent in the vertical direction.

[0043] According to this modification, the plasma generating section 10F can be easily formed simply by stacking basic units each consisting of a dielectric layer and an electrode layer (upper electrode 12 or lower electrode 13) at intervals. Furthermore, since plasma can be generated in multiple air layers 18, plasma can be generated efficiently in a small space. Furthermore, since no separate components such as spacers are required to space the basic units, multi-stage construction is easily possible, reducing manufacturing costs and shortening development time. In this way, the number of stacked electrodes can be freely changed, which has the advantage of allowing the amount of contact between plasma and gas to be controlled and devices with different capacities to be easily constructed.

[0044] The functions achieved by treating gas with plasma include sterilization, virus inactivation, deodorization, surface modification, and decomposition of chemical substances.The mechanism by which these functions are achieved is thought to be that plasma treatment generates active species in the gas, such as singlet oxygen, hydrogen peroxide, OH radicals, peroxide radicals, and ozone, which kill target microorganisms and decompose and modify chemical substances through oxidation reactions.Microorganisms include various bacteria, viruses, and mold.

[0045] The plasma-treated gas is sterilized and deodorized by killing microorganisms present in the gas and decomposing chemical substances due to the activated species generated by the plasma. Furthermore, active species remain in the plasma-treated gas, so that by spraying the plasma-treated gas generated by the plasma treatment apparatus of this embodiment onto an object, microorganisms present in the object are killed and chemical substances are decomposed, thereby sterilizing and deodorizing the object.

[0046] First Embodiment Next, a plasma processing apparatus for a storage box according to a first embodiment of the present invention will be described. As shown in Figs. 10 and 11, the plasma processing apparatus for a storage box 100 according to this embodiment is installed in a storage box 200. The storage box 200 includes a housing 201 and a plurality of shelves 202. In this embodiment, the storage box 200 is exemplified as a shoe box. The storage box 200 may be any box-shaped body for storing items, and includes, for example, a shoe cabinet, a locker, etc. Shoes S are stored inside the storage box 200.

[0047] The housing 201 is a closed or enclosed space, which is a box or a shelf-like body with one or both sides open, allowing air to circulate vertically within the housing 201. The shelf 202 is a plate-like member on which the shoes S are placed.

[0048] As shown in Figures 10 and 11, the storage box plasma processing apparatus 100 includes a plasma generating unit 10, a gas flow unit 20, a power supply unit 30, sensors 40 for ozone, temperature, humidity, etc., a wireless interface 50, and a control unit 60. The plasma generating unit 10 of this embodiment has the same basic structure as the plasma generating unit described above, but various modified examples of the plasma generating unit may also be used. One or more plasma generating units 10 may be installed.

[0049] The gas flow unit 20 is a part that causes gas to flow into the plasma generating unit 10 to treat the gas with plasma, and also supplies the plasma-treated gas into the housing 201. As also shown in Fig. 12, the gas flow unit 20 includes a housing 21, an inlet tube (inlet section) 22, an outlet tube (outlet section) 23, and a blower 24. The housing 21 is a box-shaped body that covers the plasma generating unit 10.

[0050] The housing 21 is detachably attached to the side of the storage box 200. The inlet tube 22 is a flexible cylindrical body that connects the blower 24 and the housing 21. The outlet tubes 23, 23 are flexible cylindrical bodies that connect the housing 21 and the storage box 200. The tips of the outlet tubes 23, 23 are located inside the storage box 200. The inlet tube 22 may have any other form as long as it functions as an inlet part that can supply gas to the plasma generating unit 10. In addition, the outlet tube 23 may have any other form as long as it functions as an outlet part that discharges gas that has been plasma-processed in the plasma generating unit 10.

[0051] The blower 24 supplies air to the plasma generating unit 10 and supplies plasma-converted air to the housing 201 of the storage box 200. Any known device can be appropriately selected and used. As a driving device for moving the gas, a centrifugal blower (such as a sirocco fan, radial fan, or turbo fan), an axial flow blower (such as a propeller fan), a mixed flow blower (such as a line fan), a cross flow blower, a blower, or a compressor can be appropriately used. The blower 24 operates or stops, or controls the airflow or gas discharge pressure, based on a control signal from the control unit 60. Alternatively, the blower 24 may be replaced by, for example, connecting the inlet tube 22 to the outlet of a pressurized air hose to deliver gas. In this case, the blower 24 is unnecessary. Although not shown, a filter for removing dust and dirt may be provided either before or after the blower.

[0052] The power supply unit 30 applies an AC voltage between the upper electrode 12 and the lower electrode 13, which face each other with the dielectric layer 11 sandwiched therebetween. The power supply unit 30 is connected to, for example, a power connector 31. There are no particular limitations on the power supply unit 30 as long as it can apply an AC voltage of a predetermined voltage at a predetermined frequency to each electrode of the plasma generation unit 10, and any known power supply device can be used. The frequency of the AC voltage is preferably 50 Hz to 30 MHz, and more preferably 50 Hz to 100 kHz. The AC voltage is preferably 0.1 to 50 kV, and more preferably 0.2 to 10 kV.

[0053] The sensor 40 is a sensor that monitors the conditions inside the storage box 200 and is a sensor module that includes sensors for temperature, humidity, light, infrared rays, ozone, PM2.5, CO2, etc. The measurement results are sent to the control unit 60. The sensor 40 is installed inside the storage box 200. Through these sensors, the amount of plasma generated, etc. is determined according to pre-programmed requirements, and the plasma output and air volume are controlled.

[0054] The wireless interface 50 is a component that wirelessly provides information to a mobile terminal device, a terminal device, etc. The control unit 60 transmits information related to plasma generation to the wireless interface 50. The information related to plasma generation includes, for example, the number of plasma occurrences, the amount of plasma generation (plasma density), plasma strength, voltage, current, or power consumption, operating time, the temperature of the power supply unit, the controller, the plasma generation unit, humidity, information related to the fan and pump, water temperature, error information, etc. The information transmitted to the mobile terminal device, etc. may also include, for example, the number of visitors to the facility, the amount of water, etc. The wireless interface 50 may use, for example, Bluetooth (registered trademark), Wi-Fi, NFC (Near Field Communication), an induction coil, an optical sensor, etc. The mobile terminal device may use, for example, a smartphone, a mobile phone, etc. The terminal device may use, for example, a personal computer or a tablet.

[0055] The control unit 60 is a unit that controls each part of the storage box plasma processing apparatus 100 by sending control signals to them. The control unit 60 is installed in the housing 21. The control unit 60 includes at least a calculation unit (central processing unit) and a memory unit. The control unit 60 is connected to the power connector 31 via a control unit power supply 61. The control unit power supply 61 is a unit that generates and supplies the power required for the operation of the control unit 60. The control unit 60 sends a control signal to the power supply unit 30 via a high-voltage control unit (not shown) provided within the control unit 60 to apply an AC voltage to each electrode layer (upper electrode 12 and lower electrode 13). In addition, the control unit 60 sends a control signal to the blower 24 in accordance with the application of the AC voltage to circulate air through the plasma generation unit 10.

[0056] The control unit 60 may be provided with a timer unit (not shown) that measures the date and time. The timing at which the control unit 60 applies the AC voltage can be set as appropriate. For example, the control unit 60 may be provided with a timer unit that measures the time, and plasma may be generated during a desired time period, or may be operated by a predetermined operation, or may be operated continuously.

[0057] Next, the effects of this embodiment will be described. The control unit 60 sends a control signal to the power supply unit 30 to apply an AC voltage, and operates the air blower 24 or controls the airflow rate. As a result, gas flows through the inlet tube 22, the housing 21, and the outlet tube 23, and the gas is converted into plasma by the plasma generated in the plasma generating unit 10, and the plasma-treated gas is supplied into the storage box 200. As a result, the inside of the storage box 200 can be efficiently sterilized and deodorized.

[0058] The sensor 40 can also detect the temperature, humidity, ozone concentration, and the like inside the storage box 200. When generating plasma gas as in this embodiment, ozone is generated as a by-product of oxygen treatment with plasma. The amount of activated species processed by plasma can be estimated from the concentration of the by-product ozone, humidity, plasma power, temperature, and the like. Furthermore, the plasma treatment capacity can be controlled, and operation can be started or stopped based on these measurement results. Furthermore, if the measurement results of the sensor 40 show that the calculated active ingredient continues to decrease, the calculated active ingredient remains decreased, or abnormal fluctuations in the calculated active ingredient are detected, it can detect that there is some kind of malfunction and send an error signal, or it can send error information to the user's mobile terminal device, etc. via the wireless interface 50.

[0059] Furthermore, since the system is equipped with a wireless interface 50, information regarding plasma generation can be transmitted to, for example, the user's mobile terminal device. This allows the user to understand the status of plasma generation. Furthermore, the control unit 60 can calculate the electricity charge from the amount of electricity, and this information can also be provided to the user.

[0060] Second Embodiment Next, a second embodiment of the present invention will be described. In this embodiment, a locker will be exemplified as the storage box 200A. In this embodiment, the differences from the first embodiment will be mainly described.

[0061] The storage box 200A is a locker equipped with housings 201A, 201A, and 201A. Clothes (not shown), shoes S, etc. are stored inside each housing 201A. A sensor 40 is installed in each housing 201A.

[0062] 13 (FIG. 11), the plasma processing apparatus 100A for a storage box includes a plasma generating unit 10, a gas flow unit 20, a power supply unit 30, a sensor 40, a wireless interface 50, and a control unit 60. An outflow tube (outflow unit) 23 of the gas flow unit 20 connects each housing 201A and the housing 21 of the gas flow unit 20.

[0063] As in this embodiment, the storage box 200A may be a locker, etc. Even in this case, substantially the same effects as in the first embodiment can be obtained.

[0064] Third Embodiment Next, a plasma processing apparatus 100B for a storage box according to a third embodiment of the present invention will be described, as shown in Figure 14. The plasma processing apparatus 100B for a storage box differs from the first embodiment in that multiple spaces are provided within the housing 21B, allowing gases of different pressures to be extracted. In this embodiment, the differences from the first embodiment will be mainly described.

[0065] Gas flow section 20B includes housing 21B, inlet tubes 22A, 22B, and 22C, outlet tubes 23A, 23B, and 23C, and blowers (not shown) connected to each of inlet tubes 22A, 22B, and 22C. Each blower can send gas at a different wind speed (wind pressure).

[0066] The housing 21B includes a dielectric layer 11Ba and a dielectric layer 11Bb, which divide the housing 21B into three spaces: a first space 71, a second space 72, and a third space 73. An upper electrode 12 is provided on the upper surface of the dielectric layer 11Ba, and a lower electrode 13 is provided on the lower surface of the dielectric layer 11Bb. The upper electrode 12 and the lower electrode 13 are electrically connected to a power supply unit 30. The upper electrode 12, the lower electrode 13, the dielectric layer 11Ba, the dielectric layer 11Bb, and the second space 72 (air layer) constitute a "plasma generation unit." By applying an AC voltage to the upper electrode 12 and the lower electrode 13, gas flowing through the first space 71, the second space 72, and the third space 73 can be converted into plasma. The upper electrode 12 and the lower electrode 13 may have holes or a structure with larger holes (e.g., a mesh-like structure) as needed. Furthermore, a mask layer may be provided on the upper layer electrode 12 and the lower layer electrode 13 to protect the electrodes.

[0067] In the first space 71, gas flows in through inlet tube (inlet portion) 22A, and the plasma gas is taken out through outlet tube (outlet portion) 23A. In the second space 72, gas flows in through inlet tube (inlet portion) 22B, and the plasma gas is taken out through outlet tube (outlet portion) 23B. In the third space 73, gas flows in through inlet tube (inlet portion) 22C, and the plasma gas is taken out through outlet tube (outlet portion) 23C.

[0068] Since the gas treated by plasma extracted from each space has a different pressure (air pressure), the supply destination of the gas treated by plasma can be selected according to each air pressure. For example, since a high pressure is required when sending air to a large storage box 200, the gas treated by the plasma with the highest pressure is supplied to the large storage box 200. Alternatively, the gas treated by the plasma with the next highest pressure may be supplied to a small storage box 200, and the gas treated by the plasma with the lowest pressure may be supplied to the internal space in which the storage box 200 is installed.

[0069] According to this embodiment, the gas flow unit 20B can extract gas treated with plasma at a plurality of different pressures (atmospheric pressures) from one plasma generating unit. This makes it possible to efficiently supply gas treated with plasma even when the supply destinations have different atmospheric pressure loads, such as a large storage box 200, a small storage box 200, and the internal space in which the storage box 200 is installed. Note that although three spaces are provided in this embodiment, two, four, or more may be provided.

[0070] The gas load varies depending on the situation at the supply destination. For example, sending gas to a large storage box or large locker requires a higher pressure than sending gas into the atmosphere. In such cases, installing a plasma generation unit for each atmospheric pressure increases costs and requires more installation space.

[0071] In this regard, according to this embodiment, each space is provided with an inlet tube (inlet section) and an outlet tube (outlet section), and the three spaces are independent of each other. Therefore, even if there is a malfunction in one space, plasma generation can continue in the other spaces, thereby improving the reliability of the entire device.

[0072] In addition, in the plasma generating unit as in this embodiment, a pair of electrode layers may be provided on the upper and lower surfaces of a dielectric layer as in the basic structure described above, or an air layer (space) may be provided between the pair of electrode layers via a dielectric layer as in this embodiment. Even in the latter case, plasma can be generated. Furthermore, the pressure (atmospheric pressure) of the plasma gas sent to each space need only be different from that of the other spaces in at least one location, and does not need to be different everywhere.

[0073] Although the embodiments of the present invention have been described above, appropriate design changes are possible within the scope of the present invention. For example, the control unit 60 may be provided with an input unit (such as a touch panel) and a display unit (monitor). For example, plasma may be generated based on instructions input from the input unit. Furthermore, information related to plasma generation, the amount of electricity, etc. may be displayed on the display unit. In the second embodiment, blowers with different air speeds (air pressures) are provided for the first space 71, the second space 72, and the third space 73, respectively, so that the pressure (air pressure) in each space is different. However, for example, a single blower may be used, and valves may be provided in the air flow paths through which the air passes, and the pressure in each space may be changed by adjusting the valves. Also, a single blower may be used, and the pressure in each section may be changed by adjusting the inner diameter of the flow paths. This reduces the number of blowers installed, thereby lowering equipment costs. [Explanation of symbols]

[0074] 10 Plasma generation unit 11 Dielectric layer 12 Upper layer electrode (electrode layer) 13 Lower electrode (electrode layer) 14 Upper mask layer (mask layer) 15 Lower mask layer (mask layer) 20 Gas flow section 21. Cabinet 22 Inlet tube (inlet section) 23 Outlet tube (outlet section) 30 Power supply section 40 sensors 50 Wireless Interface 60 Control Unit 100 Plasma treatment device for storage box 200 Storage Box

Claims

1. a plasma generating unit that generates plasma and includes at least a dielectric layer and a pair of electrode layers provided on both sides of the dielectric layer; a power supply unit that applies an AC voltage to the pair of electrode layers; a gas flow unit that flows a gas through the plasma generating unit to treat the gas with plasma, and supplies the gas that has been treated with plasma into the storage box.

2. a sensor for detecting plasma in the storage box; 2. The plasma processing apparatus for a storage box according to claim 1, further comprising: a control unit that receives a detection result from the sensor and transmits a signal to apply an AC voltage to the power supply unit based on the detection result.

3. 2. The plasma processing apparatus for a storage box according to claim 1, further comprising a control unit that transmits a signal to apply an AC voltage to the power supply unit based on a timer unit that measures time.

4. a wireless interface for providing information to a terminal device; a control unit that transmits a signal to apply an AC voltage to the power supply unit, 2. The plasma processing apparatus for a storage box according to claim 1, wherein the control unit transmits information about plasma generation to an external device via the wireless interface.

5. a housing that covers the plasma generating unit and is divided into a plurality of spaces by the dielectric layer; 2. The plasma processing apparatus for a storage box according to claim 1, wherein the housing has an inlet portion through which gas flows into each of the spaces and an outlet portion through which gas flows out, and is configured so that gases of different pressures flow into each of the spaces.

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