Plasma treatment apparatus for cleaning equipment

Abstract

To provide a plasma treatment apparatus for cleaning equipment by which it is possible to efficiently sterilize a cleaning object.SOLUTION: A plasma treatment apparatus for cleaning equipment includes: a plasma generation part 10 that generates plasma and includes at least a dielectric layer and a pair of electrode layers disposed on both sides of the dielectric layer; a power supply part that applies an AC voltage to the pair of electrode layers; and a gas flow part 20 that supplies gas to the plasma generation part 10 in order to treat gas with plasma, and supplies the gas treated with plasma to a cleaning facility 200 where a liquid is stored.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a plasma processing apparatus for a cleaning facility. [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, in facilities requiring sanitation management, such as livestock farms, pig farms, poultry farms, and food factories, visitors' feet, shoe soles, vehicle tires, and equipment legs may need to be washed at the entrance. While placing a water tank at the entrance and washing visitors' feet is conceivable, it may be possible to remove surface dirt, but it is not possible to sterilize any bacteria that may be present. Alternatively, adding sterilizing chemicals to the water in the tank is conceivable, but this poses problems such as the complicated process of adding the chemicals and the increased cost of the chemicals. Therefore, it is desirable to apply the cleaning capabilities of plasma.

[0006] In view of the above background, an object of the present invention is to provide a plasma treatment apparatus for a cleaning facility that can efficiently sterilize objects to be cleaned. [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 the plasma to a cleaning facility in which a liquid is stored.

[0008] According to the present invention, gas treated with plasma (also called plasma gas) can be supplied to the liquid in the cleaning equipment and contained in the liquid (this liquid is also called plasma liquid), thereby enabling efficient sterilization of the object to be cleaned.

[0009] It is also preferable to have a water level sensor that detects the water level of the cleaning equipment, a control unit that receives the detection result of the water level sensor, and a reserve tank that supplies liquid to the cleaning equipment based on the detection result of the water level sensor.

[0010] According to the present invention, it is possible to prevent the washing equipment from running out of liquid.

[0011] The present invention is also 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 plasma liquid generation unit that receives gas that has been treated with plasma in the plasma generation unit and generates a liquid that has been treated with plasma, and the liquid that has been treated with plasma in the plasma liquid generation unit is supplied to cleaning equipment in which liquid is stored.

[0012] According to the present invention, gas treated with plasma (also called plasma gas) is supplied to the liquid in the cleaning equipment and is contained in the liquid (this liquid is also called plasma liquid). This allows for efficient sterilization of objects to be cleaned. Furthermore, the inclusion of a plasma liquid generator increases the flexibility of equipment design depending on the distance between each piece of equipment and the equipment area.

[0013] The plasma generating unit is also covered with a housing that is divided into a plurality of spaces by the dielectric layer, and the housing is provided with an inlet portion through which gas flows into each space and an outlet portion through which gas flows out, for each space, and is configured so that gases of different pressures flow into each space.

[0014] According to the present invention, a plurality of plasma gases with different pressures can be supplied from one plasma generating unit, that is, plasma gases with different pressures can be supplied according to the load of the supply destination. [Effects of the Invention]

[0015] The plasma treatment device for cleaning equipment of the present invention can efficiently sterilize objects to be cleaned. It can also reduce or eliminate the use of chemicals involved in cleaning, thereby lowering disinfection costs. Furthermore, because sterilization can be performed using only electricity, it is also effective in situations where chemicals are difficult to obtain after a large-scale disaster or other incident. [Brief explanation of the drawings]

[0016] [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 cross-sectional view illustrating a plasma generating unit according to a third modified example. [Figure 7] FIG. 10 is a cross-sectional view illustrating a plasma generating unit according to a fourth modified example. [Figure 8] 1 is a schematic side view showing a plasma processing apparatus for a cleaning facility according to a first embodiment of the present invention; [Figure 9] 1 is a block diagram showing a plasma processing apparatus for a cleaning facility according to a first embodiment; [Figure 10] 1 is an enlarged side view showing a plasma processing apparatus according to a first embodiment. [Figure 11] FIG. 4 is a schematic side view showing a plasma processing apparatus for a cleaning facility according to a second embodiment of the present invention. [Figure 12] FIG. 10 is a schematic side view showing a plasma processing apparatus for a cleaning facility according to a third embodiment of the present invention. [Figure 13] FIG. 10 is a schematic side view showing a plasma processing apparatus for a cleaning facility according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] 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.

[0018] The plasma processing apparatus for cleaning equipment 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.

[0019] <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.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] The shape, number, and direction of the through holes 16, 17 relative to the gas flow can be selected appropriately depending on the purpose of the plasma processing, the effect of the plasma processing, etc. The shapes of the through holes may be different between the front and back sides of the plasma generating unit 10. Alternatively, the through holes may be provided on the front side of the plasma generating unit 10 and not on the back side.

[0032] <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.

[0033] <Second Modification of Plasma Generation Unit> 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 have an upper mask layer 14 and a lower mask layer 15. As in the plasma generating unit according to the second modified example, the upper mask layer 14 and the lower mask layer 15 may be omitted. In other words, 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.

[0034] Furthermore, as in the first and second modified examples, by omitting both or one of the upper mask layer 14 and the lower mask layer 15, the upper electrode 12 and the lower electrode 13 can be brought into direct contact with the gas, and the plasma and gas can be brought into contact at the ends of the electrodes, making it possible to easily extract the plasma gas.

[0035] <Third Modification of Plasma Generation Unit> FIG. 6 is a cross-sectional view illustrating a plasma generating unit according to a third modified example. The plasma generating unit 10C according to the third modified example differs from the basic structure in that an air layer 18 is provided below the dielectric layer 11Ca and that the upper mask layer 14 and the lower mask layer 15 are not provided. The plasma generating unit 10C also includes a dielectric layer 11Cb below the lower electrode 13. The plasma generating unit 10C includes dielectric layers 11Ca and 11Cb, the upper electrode 12, the lower electrode 13, and the air layer 18. However, since air is also considered a type of dielectric, the dielectric layers 11Ca and 11Cb and the air layer 18 can be considered as a single dielectric layer, which is the same as the basic structure shown in FIG. 2. The dielectric layer 11Cb provided below the lower electrode 13 is used to support the lower electrode 13. As in the third modified example, the upper mask layer and the lower mask layer may be omitted while providing the air layer 18 between the dielectric layer 11Ca and the lower electrode 13. Even in this configuration, it is possible to achieve substantially the same effects as the basic structure and to reduce the number of parts.

[0036] 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 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. Furthermore, the dielectric layer 11Cb plays little role in plasma generation. However, by adopting such a structure, the same structure having the upper layer electrode 12 and the lower layer electrode 13 can also be used. This reduces manufacturing costs.

[0037] In the third modified example, plasma can also be generated in the air layer 18. Note that, as in the basic structure, an upper mask layer 14 and a lower mask layer 15 may be provided on the upper surfaces of the upper electrode 12 and the lower electrode 13, respectively. Furthermore, in the third modified example, supports with pillars, grooves, protrusions, etc. that structurally support the dielectric layers 11Ca and 11Cb are not shown. The structures supporting the electrode structure may be either conductive or insulating as long as they are placed a sufficient distance from the electrodes, but insulating materials are preferred. Furthermore, structures may be placed in the air layer 18 to divide, control, or change the flow rate of the fluid passing through them. Furthermore, if these structures are made of a dielectric, the electric field can be controlled to suppress electric field concentration in specific areas, or conversely, the electric field can be intentionally concentrated.

[0038] <Fourth Modification of Plasma Generation Unit> 7 is a cross-sectional view illustrating a plasma generating unit according to a fourth modified example. The plasma generating unit 10D according to the fourth 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. That is, the plasma generating unit 10D according to the third modified example is configured by stacking two plasma generating units 10C according to the third modified example in the height direction. The ends of the dielectric layers 11Ca and 11Cb are supported by a box-shaped housing 21D.

[0039] Inside the housing 21D, 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 different polarities 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.

[0040] According to this modification, the plasma generating section 10D can be easily formed by simply stacking basic units each consisting of a dielectric layer and an electrode layer (upper layer electrode 12 or lower layer 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 it can be easily multi-staged and the plasma processing capacity can be easily changed, it is possible to reduce manufacturing costs and shorten development time.

[0041] 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.

[0042] 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.

[0043] First Embodiment Next, a plasma processing apparatus for a cleaning facility according to a first embodiment of the present invention will be described. As shown in Figures 8 and 9, the plasma processing apparatus for a cleaning facility 100 according to this embodiment is installed in a cleaning facility 200. The cleaning facility 200 includes a water tank 201 and a heater unit 202. The heater unit 202 may be omitted. Although not described here, the cleaning facility 200 may also include various other equipment, such as a water tank, a water supply pipe, and a water stop valve that stops the water supply when the tank is full.

[0044] Water tank 201 is open at the top and stores water inside. Water tank 201 is placed, for example, on the floor of the entrance to the facility or the floor of each gate. The water in water tank 201 is used as cleaning water for cleaning the feet, shoe soles, vehicle tires, legs of equipment, and other objects (to be cleaned) of people entering the facility or an area of ​​the facility. The objects to be cleaned are merely examples, and may be other objects or other parts of a person. Heater unit 202 is a device for adjusting the temperature of the water stored inside water tank 201. Note that heater unit 202 may be omitted. Also, although not shown, the water tank may have a filter to filter out mud and the like. Furthermore, a small sprayer capable of spraying this sterilizing water may be installed nearby. Furthermore, a pump or motor may be installed to agitate the water in the water tank.

[0045] As shown in Figures 8 and 9, the plasma processing apparatus 100 for cleaning equipment includes a plasma generating unit 10, a gas flow unit 20, a power supply unit 30, a water level sensor 40, a wireless interface 50, a control unit 60, and a temperature sensor 70. The plasma generating unit 10 of this embodiment has the same basic structure as the plasma generating unit described above, but the first and second modified examples of the plasma generating unit may also be used. One or more plasma generating units 10 may be installed.

[0046] The gas flow unit 20 is a part that flows gas into the plasma generating unit 10 to treat the gas with plasma, and supplies the gas treated by plasma to the cleaning equipment 200. As also shown in Fig. 10 , 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.

[0047] The inlet tube 22 is a flexible cylindrical body that connects the blower 24 and the housing 21. The outlet tube 23 is a flexible cylindrical body that connects the housing 21 and the water tank 201 of the cleaning equipment 200. The tip of the outlet tube 23 is located inside the water stored in the water tank 201 of the cleaning equipment 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 the gas that has been treated by plasma in the plasma generating unit 10.

[0048] The blower 24 supplies air to the plasma generating unit 10 and also supplies plasma-treated air to the cleaning equipment 200. Any known device can be appropriately selected and used. The driving device for moving the gas may be 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. The blower 24 operates, 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 an inlet tube 22 connected to the outlet of a pressurized air hose, for example, to deliver gas. In this case, the blower 24 is unnecessary. Furthermore, filters for capturing dust and other foreign matter may be provided at the inlet or outlet of the blower, as needed.

[0049] 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 also preferably 0.1 to 50 kV, and more preferably 0.2 to 10 kV. For compactness, it is better to increase the operating frequency.

[0050] Water level sensor 40 is a sensor that measures the water level in water tank 201. The measurement results of water level sensor 40 are sent to control unit 60. Water level sensor 40 is installed inside water tank 201. If there is a device that automatically supplies water up to a certain level by directing the outlet of the water tank toward the water surface, water level sensor 40 may be removed.

[0051] 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 generated (plasma density), plasma strength, voltage, current, or power consumption, operating time, the temperature of the power supply unit or controller, the temperature of the plasma generation unit, humidity, information related to the fan or 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.

[0052] The control unit 60 is a part that controls each part of the plasma processing apparatus 100 for cleaning equipment 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 part 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 air blower 24 in accordance with the application of the AC voltage to circulate air through the plasma generation unit 10.

[0053] The control unit 60 may also be equipped with a timer unit (not shown) that measures the date and time. The control unit 60 is also configured to receive detection results from a human presence sensor (not shown) provided in the water tank 201. 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 equipped with a timer unit that measures time, and plasma may be generated at a desired time period, or may be operated by a predetermined operation, or may be operated continuously.

[0054] The temperature sensor 70 (water temperature sensor) is a sensor that measures the water temperature in the water tank 201. The measurement results are sent to the control unit 60. Because the temperature sensor 70 can measure the water temperature in the water tank 201, it is possible to control the heater unit 202 based on the detection results and adjust the temperature to the desired level. If there is no heater unit 202, the temperature sensor 70 may be omitted. Although not explained here, temperature sensors are provided as needed to understand the status of the equipment or to detect abnormal situations. These are used to detect the operating status of the equipment, and one or more sensors may be provided as needed.

[0055] 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 treated by the plasma generated in the plasma generation unit 10, and the plasma gas is supplied into the water in the water tank 201. As a result, the water in the water tank 201 is treated by the plasma, and plasma water (plasma liquid) is produced.

[0056] For example, by immersing a user's feet (shoes) in the plasma water in the water tank 201, dirt adhering to the feet (shoes) can be removed and cleaned, and the plasma can sterilize bacteria. Furthermore, this embodiment attaches to organic matter and reduces the activity of viruses and bacteria, thereby sterilizing even chemical-resistant bacteria. Furthermore, the plasma water eliminates the need to add sterilizing chemicals, thereby reducing labor and chemical costs. Furthermore, this embodiment allows the plasma processing device 100 for cleaning equipment to operate using only electricity, so it can provide sterilization even when the chemical supply is cut off, for example, during a large-scale disaster. The control unit 60 recognizes that the cleaning equipment 200 has been used based on a detection signal from the human presence sensor, and stores this information in the memory unit along with the date and time. This also allows the frequency of use of the plasma processing device 100 for cleaning equipment to be determined.

[0057] Furthermore, in this embodiment, when feet are immersed in the plasma water in the water tank 201, the liquid, which has a lower viscosity than medicine, incorporates and penetrates a sterilizing component, allowing it to penetrate into gaps and cracks in the skin that are difficult to penetrate with a liquid with a higher viscosity, thereby achieving a sterilizing (disinfecting) effect. Furthermore, when used for 5 to 10 minutes or more, the skin is softened and softened, allowing even bacteria lurking deep within the skin to be sterilized. Furthermore, by appropriately enlarging the size of the water tank 201, even large objects to be cleaned (such as vehicle tires and the legs of various machines) can be sterilized (disinfected). Furthermore, it is expected to be effective against viruses that are difficult to disinfect with alcohol alone or chlorine alone.

[0058] Furthermore, the temperature sensor 70 detects the water temperature, and the measurement result is sent to the control unit 60. By operating the heater unit 202 in accordance with this measurement result, the water temperature can be adjusted, so that the water can be used in winter or in cold regions without freezing. Note that if heating is not required, the heater unit 202 may be omitted.

[0059] Furthermore, if the measurement results of the water level sensor 40 show that the water level is continuously decreasing, the water level remains low, or abnormal fluctuations in the water level are detected, it will detect that there is some kind of malfunction and send an error signal to stop the plasma processing device 100 for cleaning equipment, or it can send error information to the user's mobile terminal device, etc. via the wireless interface 50.

[0060] The plasma generating unit 10 is covered with a housing 21 and is attached, for example, to the outside of the water tank 201. This does not interfere with the use of the cleaning equipment 200 and allows the plasma generating unit 10 to be separated from the water. This makes it possible to prevent equipment failure caused by water. Furthermore, the plasma processing apparatus 100 for cleaning equipment of this embodiment can be easily installed not only in a new cleaning equipment 200 but also in an existing cleaning equipment 200. If necessary, a filter for removing dust and the like may be provided at the input portion of the inflow tube 22.

[0061] Second Embodiment Next, a plasma processing apparatus 100A for a cleaning facility according to a second embodiment of the present invention will be described, as shown in Fig. 11. The plasma processing apparatus 100A for a cleaning facility differs from the first embodiment in that it includes a reserve tank 28. In this embodiment, the differences from the first embodiment will be mainly described.

[0062] The plasma processing device 100A for cleaning equipment is installed in the cleaning equipment 200A and includes a plasma generation unit 10, a gas flow unit 20, a power supply unit 30, a water level sensor 40, a wireless interface 50, a control unit 60, a temperature sensor 70, and a reserve tank 28.

[0063] Reserve tank 28 is a facility capable of storing water (liquid). Pipe 29 is a pipe that connects water tank 201 and reserve tank 28. One end of pipe 29 is connected to reserve tank 28 and serves as an outlet for water. The other end of pipe 29 is located inside water tank 201. Pipe 29 is provided with a valve (for example, an electromagnetic valve, not shown) that can be opened and closed based on a control signal from control unit 60.

[0064] In this embodiment, when the measurement value transmitted from the water level sensor 40 falls below a predetermined threshold, the control unit 60 transmits a control signal to open the valve for a predetermined period of time. This causes a predetermined amount of water to flow from the reserve tank 28 to the water tank 201, replenishing the water. This embodiment makes it possible to prevent the water tank 201 from running out of water (lack of liquid). Note that, although the reserve tank 28 is provided in this embodiment, other configurations may be used as long as they can replenish the water so that a predetermined amount of water is stored in the water tank 201.

[0065] Third Embodiment Next, a plasma processing apparatus 100B for a cleaning facility according to a third embodiment of the present invention will be described, as shown in Fig. 12. The plasma processing apparatus 100B for a cleaning facility differs from the first embodiment in that it includes a plasma water generating unit (plasma liquid generating unit) 25. In this embodiment, the differences from the first embodiment will be mainly described.

[0066] The plasma processing device 100B for cleaning equipment is installed in the cleaning equipment 200B and includes a plasma generation unit 10, a gas flow unit 20B, a power supply unit 30, a water level sensor 40, a wireless interface 50, a control unit 60, a temperature sensor 70, and a plasma water generation unit 25.

[0067] The plasma water generation unit 25 includes a container in which water is stored. The plasma water generation unit 25 receives the plasma gas generated by the plasma generation unit 10 and processes the stored water with plasma to generate plasma water. The inlet pipe 26 and outlet pipe 27 are pipes that connect the plasma water generation unit 25 to the water tank 201. In this embodiment, the plasma water generated by the plasma water generation unit 25 is supplied into the water tank 201 via the outlet pipe 27. The water in the water tank 201 returns to the plasma water generation unit 25 via the inlet pipe 26. In other words, water circulates between the plasma water generation unit 25 and the water tank 201.

[0068] The plasma generating unit 10, which is covered by the housing 21, may not be able to be installed outside or near the water tank 201 due to factors such as limited installation space. According to this embodiment, the plasma water generated by the plasma water generating unit 25 can be supplied to the water tank 201 via the outlet pipe 27. Therefore, the plasma processing apparatus for cleaning equipment can be applied even in places with limited installation space. Furthermore, by providing the plasma water generating unit 25, the degree of freedom in equipment design can be increased depending on the distance between each piece of equipment and the equipment area.

[0069] <Fourth embodiment> Next, a plasma processing apparatus 100C for a cleaning facility according to a fourth embodiment of the present invention will be described, as shown in Figure 13. The plasma processing apparatus 100C for a cleaning facility differs from the first embodiment in that multiple spaces are provided within the housing 21C, allowing gases of different pressures to be extracted. In this embodiment, the differences from the first embodiment will be mainly described.

[0070] Gas flow section 20C includes housing 21C, 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).

[0071] The housing 21C includes a dielectric layer 11Aa and a dielectric layer 11Ab, which divide the housing 21C 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 11Aa, and a lower electrode 13 is provided on the lower surface of the dielectric layer 11Ab. 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 11Aa, the dielectric layer 11Ab, 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 treated with 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.

[0072] 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.

[0073] The plasma gas extracted from each space has a different pressure (air pressure), so the supply destination of the plasma gas can be selected depending on the air pressure. For example, a large water tank 201 used to wash vehicle tires, etc., requires a high pressure, so plasma gas with a high pressure is supplied to water tank 201. On the other hand, a small water tank 201 used to wash shoe soles requires a low pressure, so plasma gas with the lowest pressure is supplied to water tank 201.

[0074] According to this embodiment, the gas flow unit 20C can extract plasma gas at a plurality of different pressures (atmospheric pressures) from one plasma generation unit. This allows the plasma gas to be supplied efficiently even when there are a plurality of sizes of water tank 201 and the pressure loads of the supply destinations are different. Although three spaces are provided in this embodiment, two, four or more may be provided.

[0075] The gas load varies depending on the supply destination. For example, sending gas into a large water tank requires a higher pressure than sending gas into a small water tank. In such cases, installing a plasma generator for each air pressure increases costs and requires more installation space.

[0076] In this regard, according to this embodiment, each space is provided with an inlet tube (inlet portion) and an outlet tube (outlet portion), and the three spaces are independent of each other, so that 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. Also, for example, since plasma gas can be supplied to the atmosphere near the entrance in addition to the large and small water tanks, the area to be sterilized can be increased.

[0077] 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.

[0078] Although the embodiment of the present invention has been described above, appropriate design changes are possible within the scope of the present invention. In this embodiment, the washing equipment 200 including the water tank 201 has been illustrated, but any shape is acceptable as long as it is capable of storing water and allowing feet and other objects to be immersed. For example, it may be a shape in which a depression is provided on a flat surface to store water.

[0079] In addition, in this embodiment, plasma water is generated by supplying gas treated with plasma to water, but it may also be a liquid other than water, or a mixture of water and other liquid.

[0080] The control unit 60 may also 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. Information related to plasma generation, the amount of electricity, the amount of water, etc. may also be displayed on the display unit. In the fourth 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 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]

[0081] 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) 25 Plasma water generation unit (plasma liquid generation unit) 30 Power supply section 40 Water level sensor 60 Control Unit 70 Temperature Sensor 100 Plasma treatment device for cleaning equipment 200 Cleaning Equipment

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 plasma processing apparatus for cleaning equipment, comprising: a gas flow unit that flows a gas through the plasma generating unit to process the gas with plasma, and supplies the gas processed by the plasma to cleaning equipment in which a liquid is stored.

2. a water level sensor that detects the water level of the cleaning equipment; a control unit that receives the detection result of the water level sensor; 2. The plasma processing apparatus for a cleaning facility according to claim 1, further comprising: a reserve tank for supplying liquid to the cleaning facility based on a detection result of the water level sensor.

3. 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 plasma liquid generating unit that receives the gas treated with plasma in the plasma generating unit and generates a liquid treated with plasma, A plasma treatment apparatus for cleaning equipment, characterized in that the liquid treated with plasma in the plasma liquid generating section is supplied to a cleaning equipment in which a liquid is stored.

4. a housing that covers the plasma generating unit and is divided into a plurality of spaces by the dielectric layer; The plasma processing apparatus for cleaning equipment described in any one of claims 1 to 3, characterized in that the housing has an inlet portion through which gas flows into each space and an outlet portion through which gas flows out, and is configured so that gases of different pressures flow into each space.

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