High-speed nanodroplet generation device

Abstract

This high-speed nanodroplet generation device generates high-speed nanodroplets, namely, a group of droplets that have a particle size of 1-1,000 nm and fly at a speed of 1-1,000 m / s. The high-speed nanodroplet generation device comprises: a spraying part for spraying out the high-speed nanodroplets; a first fluid supply part for supplying a first fluid containing water vapor toward the spraying part; and a second fluid supply part for supplying a second fluid toward the spraying part at a supply pressure exceeding one atmosphere. The spraying part includes a first opening for spraying out the first fluid and a second opening for spraying out the second fluid.

Description

High-speed nanodroplet generator

[0001] The present invention relates to a high-speed nanodroplet generator for generating high-speed nanodroplets, which are a group of droplets flying at high speed. This application claims priority to Japanese Patent Application No. 2024-145813, filed on August 27, 2024, the contents of which are incorporated herein by reference.

[0002] Cleaning technologies using a mixed jet of steam and water have been developed. For example, Non-Patent Document 1 discloses a technology that can clean particles, photoresist, and the like on a wafer surface without using chemicals by mixing water with constant-pressure steam and spraying it from a nozzle.

[0003] Furthermore, Non-Patent Document 2 discloses a technique for removing dental plaque using minute droplets, in which minute droplets are sprayed at high speed at a pressure of 0.15 MPa from a handpiece equipped with an air nozzle and a water nozzle.

[0004] As an example of an apparatus for generating and spraying high-speed nano droplets, Patent Document 1 discloses a high-speed nano mist generating apparatus that uses water as the high-speed nano mist (high-speed nano droplets) and generates high-speed nano mist by spraying water vapor from the water contained in a sealed container and pressurized gas supplied to the sealed container from a spray nozzle provided in the sealed container.

[0005] Furthermore, as nozzles for injecting fluid, for example, Patent Documents 2 to 4 each disclose a double nozzle having a central opening and an annular opening surrounding the central opening.

[0006] International Publication No. 2022 / 092069 Japanese Patent Publication No. 2004-202316 U.S. Patent No. 6,267,301 Chinese Patent Publication No. 115155832

[0007] Toshiyuki Sanada et al., "Development of Cleaning Technology Using a Mixed Jet of Steam and Water," Jet Engineering Vol. 24, No. 3 (2007) 4-10. Satoshi Uehara et al. Removal Mechanism of Artificial Dental Plaque by Impact of Micro-Droplets, ECS Journal of Solid State Science and Technology, 8(2) N20-N24 (2019).

[0008] The inventors conducted extensive research into mixed jets of steam and non-condensable gas and discovered that spraying nano-sized droplets at high speed onto an object or an object in a target space (high-speed nano-droplets) makes it possible to perform cleaning, sterilization, and surface treatment with unprecedented functions.

[0009] However, the high-speed nano-mist generator disclosed in Patent Document 1 has problems such as a short spray distance that the high-speed nano-droplets can reach and a tendency for condensation (wetting) of the target object due to the spray of high-speed nano-droplets. Furthermore, there is a demand for further temperature reduction of high-speed nano-droplets within the spray range where specific effects such as cleaning and sterilization can be achieved.

[0010] Furthermore, the two-fluid cleaning nozzle disclosed in Patent Document 2 is a liquid cleaning nozzle that sprays cleaning liquid from a central opening and pressurized gas from peripheral openings, and does not describe a flow path for gas containing water vapor that is involved in the formation of high-speed nanodroplets.

[0011] Furthermore, the spray nozzle disclosed in Patent Document 3 is a nozzle for generating a flat spray pattern, and has an orifice in the center that ejects liquid, and air passages around it that eject pressurized air, but there is no description of a flow path for gas containing water vapor that is involved in the formation of high-speed nanodroplets.

[0012] Furthermore, the spray head disclosed in Patent Document 4 is configured such that liquid is supplied to a central tube from a liquid supply mechanism and sprayed from the liquid spray section together with gas supplied from a gas supply mechanism, and there is no description of a flow path for gas containing water vapor involved in the formation of high-speed nanodroplets.

[0013] The present invention has been proposed in consideration of the above-mentioned problems, and aims to provide a high-speed nano-droplet generating device that can further extend the spray distance of high-speed nano-droplets, prevent condensation (wetting) of the sprayed object due to the spraying of high-speed nano-droplets, and further reduce the temperature of the high-speed nano-droplets.

[0014] The inventors have discovered that by separating the water vapor supply and the gas supply, making it possible to control the temperature and pressure of each separately, and by spraying the water vapor and gas from separate openings, it is possible to further extend the spray distance of high-speed nanodroplets, prevent condensation (wetting) of the sprayed object due to the spraying of high-speed nanodroplets, and further reduce the temperature of the high-speed nanodroplets.

[0015] In order to solve the above problems, a high-speed nano-droplet generating device according to one embodiment of the present invention proposes the following measures: (1) A high-speed nano-droplet generating device according to a first aspect of the present invention is a high-speed nano-droplet generating device that generates high-speed nano-droplets, which are groups of droplets having a particle diameter of 1 nm to 1000 nm and flying at a speed of 1 m / s to 1000 m / s, comprising: an ejection unit that ejects high-speed nano-droplets containing a first fluid and a second fluid; a first fluid supply unit that supplies the first fluid containing water vapor toward the ejection unit; and a second fluid supply unit that supplies the second fluid toward the ejection unit at a supply pressure exceeding 1 atmosphere, wherein the ejection unit has a first opening through which the first fluid is ejected and a second opening through which the second fluid is ejected.

[0016] (2) Aspect 2 of the present invention is directed to the high-speed nano-droplet generating device of aspect 1, wherein the second opening is annularly opened so as to surround the first opening when viewed in a plan view from the direction of ejection of the high-speed nano-droplets.

[0017] (3) Aspect 3 of the present invention is directed to the high-speed nano-droplet generating device of aspect 2, wherein the opening end of the second opening is formed downstream of the opening end of the first opening along the ejection direction of the high-speed nano-droplets.

[0018] (4) Aspect 4 of the present invention is a high-speed nanodroplet generating device according to any one of aspects 1 to 3, wherein the second fluid includes at least one of a gas, a liquid other than water, or a particulate solid.

[0019] (5) Aspect 5 of the present invention is the high-speed nano-droplet generating device of aspect 4, wherein the second fluid supply unit further includes a powder supply unit that supplies powder that is the fine particle solid.

[0020] (6) Aspect 6 of the present invention is a high-speed nanodroplet generating device according to any one of aspects 1 to 5, wherein the first fluid supply unit has a water tank for storing water, and a water heating means for heating the water in the water tank to generate water vapor.

[0021] (7) Aspect 7 of the present invention is a high-speed nanodroplet generating device according to any one of aspects 1 to 5, wherein the first fluid supply unit has a water tank for storing water, and an ultrasonic vibrator for applying ultrasonic waves to the water in the water tank to generate minute droplets of water that serve as a source of water vapor.

[0022] (8) Aspect 8 of the present invention is a high-speed nanodroplet generating device according to aspect 6 or 7, wherein the second fluid supply unit has a gas heating means for heating gas, and the water heating means and the gas heating means can be individually and independently controlled in temperature.

[0023] (9) Aspect 9 of the present invention is the high-speed nanodroplet generating device of any one of aspects 1 to 8, wherein the temperature of the second fluid at the second opening is higher than the temperature of the first fluid at the first opening.

[0024] According to the present invention, it is possible to provide a high-speed nano-droplet generating device that can further extend the spray distance of high-speed nano-droplets, prevent condensation (wetting) of the spray target due to the spraying of high-speed nano-droplets, and further reduce the temperature of the high-speed nano-droplets.

[0025] FIG. 1 is a schematic configuration diagram showing a high-speed nano-droplet generation device according to a first embodiment of the present invention. FIG. 1 is an enlarged cross-sectional view of a main part showing an opening portion of a jetting portion. FIG. 2 is a plan view showing the shape of the opening portion when the jetting portion is viewed in plan from the jetting direction of high-speed nano-droplets. FIG. 2 is an explanatory diagram showing the operation of the jetting portion. FIG. 3 is a schematic cross-sectional view showing an example of the shape of the peripheral portion of the first opening inside the second opening. FIG. 4 is a schematic cross-sectional view showing an example of the shape of the peripheral portion of the first opening inside the second opening. FIG. 5 is a schematic view showing another example of forming the first opening and the second opening of the jetting portion. FIG. 6 is a schematic view showing another example of forming the first opening and the second opening of the jetting portion. FIG. 7 is a schematic configuration diagram showing a first fluid supply unit in a high-speed nano-droplet generation device according to a third embodiment of the present invention. FIG. 8 is a schematic configuration diagram showing a modified example of a high-speed nano-droplet generation device according to a fourth embodiment of the present invention.

[0026] Hereinafter, a high-speed nanodroplet generating device according to one embodiment of the present invention will be described with reference to the drawings. Note that the embodiment shown below is specifically described to provide a better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified. Furthermore, the drawings used in the following description may show essential parts enlarged for convenience in order to make the features of the present invention easier to understand, and the dimensional ratios of each component may not necessarily be the same as in reality.

[0027] In the following embodiments, high-speed nanodroplets are droplets with a particle size of 1 nm to 1000 nm, and are a group of droplets flying at a speed of 1 m / s to 1000 m / s.

[0028] [First Embodiment] Fig. 1 is a schematic diagram showing a high-speed nano-droplet generating device according to a first embodiment of the present invention. Fig. 2 is an enlarged cross-sectional view of a main portion showing an opening of an ejection unit. Fig. 3 is a plan view showing the shape of the opening when the ejection unit is viewed from the ejection direction of the high-speed nano-droplets. A high-speed nano-droplet generating device 10 according to this embodiment includes an ejection unit 13 that ejects high-speed nano-droplets M, a first fluid supply unit 11 that supplies a first fluid R1 containing water vapor toward the ejection unit 13, a second fluid supply unit 12 that supplies a second fluid R2 toward the ejection unit 13, and a control unit 14. The high-speed nano-droplets M contain the first fluid R1 and the second fluid R2.

[0029] (First Fluid Supply Unit) The first fluid supply unit 11 is a supply mechanism that supplies a fluid containing water vapor that constitutes the first fluid R1, water vapor in this embodiment, and includes a water tank 21 that stores water W, a heater 22 that is water heating means that heats the water W in the water tank 21 to generate water vapor, and a water vapor supply pipe 23. The first fluid supply unit 11 also includes a preheating gas supply device 25 that supplies heated pressurized gas toward the water tank 21.

[0030] The water tank 21 may be any heat-resistant container that can be heated by the heater 22 and may be provided with a thermometer 24 that measures the temperature of the stored water W. The water tank 21 may also be connected to a water source (not shown) that continuously supplies water from an external source.

[0031] The heater 22 may be provided inside or outside the water tank 21. The heater 22 boils the water in the water tank 21 to generate a pressurized gas R1 containing water vapor at a temperature of, for example, 130° C. or higher and 160° C. or lower (first fluid: hereinafter referred to as a water vapor-containing gas) and supply it to the injection unit 13 described below. Here, the supply pressure of the pressurized gas may be approximately 0.2 MPa or higher and 1.1 MPa or lower (absolute pressure).

[0032] The preheating gas supply device 25 sends air heated to, for example, about 100°C toward the water tank 21, and generates a water vapor-containing gas mixed with the water vapor generated by boiling the water W in the water tank 21. The preheating gas supply device 25 may be composed of, for example, a cylinder that supplies pressurized air, a heater that heats the air, etc.

[0033] (Second fluid supply section) The second fluid supply section 12 is a supply mechanism that supplies the gas that constitutes the second fluid R2, which in this embodiment is air, and is composed of a gas source 26, a pressure adjustment valve 27, and a gas heating device 28 connected by a gas supply pipe 29.

[0034] The gas source 26 may be, for example, a high-pressure gas cylinder. Such a high-pressure gas cylinder can supply air, which is the second fluid R2, at a supply pressure exceeding 1 atmosphere (0.1 MPa). The upper limit of the supply pressure of the high-pressure gas is not particularly limited, but may be 1.1 MPa (absolute pressure).

[0035] In addition, when the gas constituting the second fluid R2 is air, as in this embodiment, the gas source can be constituted by a pump that can take in air from the atmosphere and deliver it at a pressure exceeding 1 atmosphere, instead of a high-pressure gas cylinder.

[0036] In this embodiment, air is used as the second fluid R2, but other gases such as oxygen, nitrogen, and carbon dioxide can also be used, which impart a specific chemical action to the generated high-velocity nanodroplets M. In this case, a high-pressure gas cylinder containing a specific gas at high pressure can be used as the gas source 26.

[0037] The second fluid R2 may include any type of gas, mixed gas, or mixture of any solid (powder) or any particulate liquid, such as a supply gas such as air alone, a gas obtained by mixing a substance other than the supply gas with the supply gas, a gas obtained by mixing a supply gas with a particulate solid (powder) or particulate liquid, or a gas obtained by mixing a substance other than the supply gas with the supply gas and further mixing the same with a particulate solid (powder) or particulate liquid.

[0038] In addition, for the second fluid R2, substances other than the supply gas can be added by various supply methods, such as supplying the substance as a gas in the initial state, or generating a gas by evaporating a liquid or sublimating a solid, and then supplying the gas.

[0039] The pressure regulating valve 27 precisely adjusts the supply pressure of the second fluid R2 supplied from the gas source 26, and may be composed of, for example, a gas valve, a gas flow meter, etc. Note that such a pressure regulating valve 27 does not necessarily have to be provided as long as the supply pressure of the second fluid R2 can be precisely adjusted in the gas source 26.

[0040] The gas heating device 28 heats the second fluid R2 supplied from the gas source 26 via the pressure regulating valve 27 to a temperature above room temperature, and may be composed of a pressure vessel 28a for temporarily storing the second fluid R2, a heater 28b for heating the pressure vessel 28a, a thermometer 28c, etc.

[0041] Such a gas heating device 28 uses a heater (gas heating means) 28b to heat the temperature of the second fluid R2 in the pressure vessel 28a to above room temperature, for example, to a temperature of about 30°C to 180°C, and supplies the heated air (second fluid: hereinafter referred to as jet gas) R2 to the injection section 13 described later.

[0042] (Ejection unit) The ejection unit 13 ejects high-speed nano-droplets M containing a first fluid R1 and a second fluid R2, which are supplied respectively from a first fluid supply unit 11 and a second fluid supply unit 12 that are independent of each other, toward the ejection target surface S.

[0043] The injection unit 13 is composed of a first flow path 33 having one end connected to the steam supply pipe 23 of the first fluid supply unit 11 and the other end forming a first opening 31, a second flow path 34 having one end connected to the gas supply pipe 29 of the second fluid supply unit 12 and the other end forming a second opening 32, and a housing 35 that forms the first flow path 33 and the second flow path 34 inside.

[0044] It is also preferable to further provide an on-off valve, a flow rate control valve, or the like, in the water vapor supply pipe 23 of the first fluid supply unit 11. By providing such an on-off valve or a flow rate control valve in the water vapor supply pipe 23, it is possible to freely control the start and stop of the spraying of the water vapor-containing gas (first fluid) R1 to be sprayed from the first opening 31 of the spray unit 13, or the amount of spraying.

[0045] It is also preferable to further provide an on-off valve, a flow rate control valve, or the like in the gas supply pipe 29 of the second fluid supply unit 12. By providing such an on-off valve or a flow rate control valve in the gas supply pipe 29, it is possible to freely control the start and stop of the jet gas (second fluid) R2 to be sprayed from the second opening 32 of the spray unit 13, or the amount of spray.

[0046] In the ejection unit 13 of this embodiment, in a horizontal plane perpendicular to the ejection direction L of the high-speed nano-droplets M, a first flow path 33 is arranged at the center, and a second flow path 34 is formed to surround the first flow path 33.

[0047] The first opening 31 of the injection part 13 of this embodiment is disposed at the center of one end of the housing 35 and is formed so that the opening surface is circular. The second opening 32 is formed so that the opening surface is annular (ring-shaped) and surrounds the first opening 31.

[0048] The diameter of the first opening 31 is, for example, about 0.2 mm to 1.0 mm, and in this embodiment, it is 0.4 mm. The radial width of the second opening 32 is, for example, about 0.2 mm to 0.6 mm, and the distance between the outer periphery of the first opening 31 and the inner periphery of the second opening 32 may be about 0.4 mm to 1.0 mm, and may be about 0.6 mm to 1.0 mm.

[0049] When the diameter of the first opening 31 is 0.4 mm or more, the supply pressure of the first fluid R1 from the first opening 31 can be set to about 0.2 MPa or more and 1.1 MPa or less (absolute pressure), which is preferable.

[0050] The diameter of the first opening 31 may be, for example, about 0.5 mm to 1.0 mm, and in this case, the radial width of the second opening 32 may be, for example, about 0.2 mm to 0.6 mm, and the distance between the outer periphery of the first opening 31 and the inner periphery of the second opening 32 may be, for example, about 0.35 mm to 1.0 mm.

[0051] When the diameter of the first opening 31 is 0.5 mm or more, the supply pressure of the first fluid R1 from the first opening 31 can be set to approximately 0.2 MPa or more and 1.1 MPa or less (absolute pressure), which is preferable. In this embodiment, when the diameter of the first opening 31 is 0.5 mm or more, the supply pressure of the first fluid R1 can be increased, thereby improving the cleaning power of the high-speed nano-droplets M. In particular, when the supply pressure of the first fluid R1 can be set to approximately 1.1 MPa (absolute pressure), the spray distance of the high-speed nano-droplets can be further extended and their speed can be accelerated, resulting in preferable cleaning power.

[0052] From the viewpoint of durability, the injection part 13 is preferably made of stainless steel, and for example, SUS303, SUS316, or the like can be used.

[0053] In the injection part 13 of this embodiment, the opening end of the second opening 32 is formed downstream (forward) of the opening end of the first opening 31 along the injection direction L of the high-speed nano-droplets M. For example, in this embodiment, the opening end of the first opening 31 is formed inside a recess 36 that is formed by recessing the inside of the opening end of the annular second opening 32 in the opposite direction to the injection direction L, so that the opening end of the second opening 32 protrudes further in the injection direction L than the opening end of the first opening 31.

[0054] Furthermore, the first flow path 33 of the ejection part 13 of this embodiment is formed to have a tapered shape such that the cross-sectional area thereof becomes smaller toward the first opening 31 in the ejection direction L inside the housing 35. The second flow path 34 is also formed to have a tapered shape such that the cross-sectional area thereof becomes smaller toward the second opening 32 in the ejection direction L inside the housing 35. The cross-sectional area is the area of ​​a cross section of the ejection part 13 taken along the ejection direction L.

[0055] The housing 35 may have a double-pipe structure including a second cylindrical pipe and a first cylindrical pipe disposed inside the second cylindrical pipe. When the first flow path 33 has a tapered shape such that the cross-sectional area decreases toward the first opening 31 in the spray direction L, the tip of the first cylindrical pipe may have a conical shape (tapered shape), or the diameter of the first cylindrical pipe constituting the first flow path 33 may be gradually reduced. The second flow path 34 may be a flow path disposed between the inner circumferential surface of the second cylindrical pipe disposed inside the housing 35 and the outer circumferential surface of the first cylindrical pipe disposed inside the second cylindrical pipe. When the second flow path 34 has a tapered shape such that the cross-sectional area decreases toward the second opening 32 in the spray direction L, the inner circumferential surface of the second cylindrical pipe at the tip may have a conical shape (tapered shape), or the diameter of the second cylindrical pipe may be gradually reduced.

[0056] The first flow path 33 may be filled with a fibrous filler. Even if there is a temperature difference between the first flow path 33 and the second flow path 34 and condensation occurs on the inner wall of the first flow path 33, if the first flow path 33 is filled with a fibrous filler, the water condensing on the wall of the first flow path 33 is drawn back into the first flow path 33 due to the capillary effect of the fibrous filler and vaporized by the heat inside, thereby preventing water from accumulating in the first flow path 33. The filler is not particularly limited as long as it can achieve a capillary effect, but it is preferable that it is made of a material that does not react with water vapor and has a diameter that can achieve the capillary effect. Specifically, the filler is preferably a filler having a structure that can achieve a capillary effect, such as a fibrous filler, a granular filler, a honeycomb-shaped filler, or a porous material. Furthermore, the filler material can be one or more selected from the group consisting of quartz glass, stainless steel, artificial minerals, ceramics, and glass. The filling rate of the fibrous filler in the first flow path 33 is not particularly limited, but is preferably set to a level that does not cause pressure loss and does not hinder the ejection of steam from the first opening 31.

[0057] (Control unit) The control unit 14 performs temperature settings and flow rate settings for the preheating gas supply device 25 and heater 22 of the first fluid supply unit 11, and the pressure adjustment valve 27 and gas heating device 28 of the second fluid supply unit 12, and independently controls the flow rate, temperature, etc. of the water vapor-containing gas (first fluid) R1 sprayed from the first opening 31 of the injection unit 13 and the jet gas (second fluid) R2 sprayed from the second opening 32.

[0058] The control unit 14 may be configured, for example, as a PID (Proportional-Integral-Differential) temperature control device, etc. Alternatively, the control unit 14 may be configured as a microcomputer equipped with a CPU, memory, etc., and an interface for connecting with each device.

[0059] Next, the operation and function of the high-speed nanodroplet generating device 10 of this embodiment configured as described above will be described. When using the high-speed nanodroplet generating device 10 of this embodiment to generate and spray high-speed nanodroplets, which are groups of droplets with a diameter of 1 nm to 1000 nm and flying at a speed of 1 m / s to 1000 m / s, the control unit 14 is first operated to set the flow rate of the preheating gas supplied from the preheating gas supply device 25 of the first fluid supply unit 11, the set temperature (temperature of the water in the water tank 21) of the heater 22 of the first fluid supply unit 11, the temperature of the jet gas R2 supplied by the gas heating device 28 of the second fluid supply unit 12, and the flow rate of the jet gas R2 supplied by the pressure adjustment valve 27. This sets the temperature and flow rate of the water vapor-containing gas (first fluid) R1 and the temperature and flow rate of the jet gas (second fluid) R2.

[0060] Then, when spraying is started from the high-speed nanodroplet generating device 10, a water vapor-containing gas (first fluid) R1 is sprayed from the first opening 31 of the spray section 13, and a jet gas (second fluid) R2 is sprayed from the second opening 32 independently of each other toward the spray target surface (spray target) S in the spray direction L.

[0061] When the water vapor-containing gas R1 and the jet gas R2 are sprayed from the spray section 13, the first flow path 33 of the spray section 13 has a tapered shape in which the cross-sectional area becomes smaller as it approaches the first opening 31 in the spray direction L inside the housing 35, so that the water vapor-containing gas R1 does not expand inside the spray section 13 and the temperature does not drop.

[0062] Similarly, the second flow path 34 has a tapered shape in which the cross-sectional area becomes smaller as it approaches the second opening 32 in the injection direction L inside the housing 35, so that the expansion of the jet gas R2 does not occur inside the injection section 13 and the temperature does not decrease.

[0063] Therefore, the water vapor-containing gas R1 and the jet gas R2 are cooled after being ejected to the outside from the first opening 31 and the second opening 32. Therefore, the set ejection temperatures of the water vapor-containing gas R1 and the jet gas R2 hardly change until the water vapor-containing gas R1 and the jet gas R2 reach the first opening 31 and the second opening 32, respectively.

[0064] In addition, as in this embodiment, by forming the opening end of the second opening 32 to protrude further in the injection direction L than the opening end of the first opening 31, the generation area of ​​the circulating flow formed outside the first opening 31 is narrowed, as shown in Figures 4, 5A, and 5B. Since the second opening 32 that ejects the jet gas R2 protrudes further in the injection direction L than the first opening 31, the temperature of the second flow path 34 is high, and this heat can heat the tip side of the injection part 13.

[0065] Furthermore, a circulating flow is formed at the tip end of the heated injection part 13 by the injection of the water vapor-containing gas R1 from the first opening 31, so that the high-temperature jet gas R2 can always flow from the tip end of the injection part 13. This makes it possible to prevent condensation on the tip end of the injection part 13 where the first opening 31 and the second opening 32 are formed.

[0066] Furthermore, by setting the temperature of the jet gas R2 at the second opening 32 higher than that of the water vapor-containing gas R1 at the first opening 31, for example, by 5°C or more, it is possible to prevent condensation from occurring near the first opening 31, where it is difficult to install a heater. This prevents liquefied water droplets (water droplets) from mixing with the water vapor-containing gas R1, and the water vapor-containing gas R1 jetted from the first opening 31 is entirely composed of vaporized water (water vapor) and air.

[0067] In this way, the water vapor-containing gas R1 from the first opening 31 of the injection section 13 is sprayed by the jet gas R2 from the second opening 32, and the distance over which the gas flies in the injection direction L while maintaining a specific functionality, such as a cleaning effect, i.e., the injection distance F, is significantly extended compared to when the water vapor-containing gas R1 is sprayed alone.

[0068] For example, when the water vapor-containing gas R1 is sprayed alone under the same spray conditions, the spray distance is less than 5 mm, whereas by spraying the jet gas R2 independently in the vicinity of the water vapor-containing gas R1, the spray distance of the high-speed nanodroplets M while maintaining the cleaning effect can be extended to several tens of mm, for example, about 40 mm.

[0069] Furthermore, at the target surface S, which is the surface reached by the high-speed nanodroplets M that maintain this cleaning effect, the cleaning effect is maintained even if the supply amount of water vapor-containing gas R1 is reduced, so the target surface S is prevented from wetting with liquefied water and the target surface S is kept dry.

[0070] As described above, according to the high-speed nano-droplet generating device 10 of this embodiment, by spraying a water vapor-containing gas (first fluid) R1 from the first opening 31 and spraying a jet gas (second fluid) R2 from the second opening 32, it is possible to extend the spray distance of high-speed nano-droplets M having specific functionality, such as a cleaning effect or a sterilization effect, prevent condensation (wetting) on ​​the target surface S due to the spraying of the high-speed nano-droplets M, and further enable the high-speed nano-droplets M to be cooled.

[0071] The first fluid of the high-speed nanodroplet generating device 10 of this embodiment is composed of water vapor and air, but the first fluid may be any gas that contains at least water vapor, for example, water vapor alone, water vapor and nitrogen gas, water vapor and oxygen gas, etc.

[0072] The second fluid may also contain at least one of a gas, a liquid other than water, or a particulate solid. For example, the second fluid may preferably contain air and a disinfectant powder as a particulate solid.

[0073] Furthermore, such liquids other than water or particulate solids that can be contained in the second fluid may be substances that react with the water vapor that constitutes the first fluid to produce compounds having specific functions, etc. Furthermore, a substance that reacts with liquids other than water or particulate solids that can be contained in the second fluid may also be added to the first fluid.

[0074] As a configuration in which such a second fluid contains powder, for example, a powder supply unit 81 is connected to the middle of the gas supply pipe 29 of the second fluid supply unit 12 shown in FIG. 1 , and powder is sucked from the powder supply unit 81 by a jet gas (second fluid) R2 flowing through the gas supply pipe 29 and mixed, and the powder-containing jet gas (second fluid) R2 can be sprayed from the second opening 32.

[0075] In this way, by spraying the powder-containing jet gas (second fluid) R2, a portion of the powder comes into contact with droplets of the water vapor-containing gas (first fluid) R1 sprayed from the first opening 31, and the droplets adhere to the powder surface while colliding with the spray target surface S. Then, at the time of this collision, the powder and the droplets react with each other to produce a compound having a specific function, for example, a cleaning effect or a disinfecting effect.

[0076] Therefore, by adding powder to the jet gas (second fluid) R2, the impact pressure caused by the powder colliding at high speed creates a high-temperature, high-pressure environment, which can have effects such as causing unique chemical reactions or causing droplets covering the surface of the powder to form a dissolved liquid phase on the powder surface.

[0077] As shown in Figures 5A and 5B, the shape of the peripheral portion of the first opening 31 inside the second opening 32 is not limited, and can be formed into various shapes, such as having an inclined portion.

[0078] Specifically, in Fig. 5A, the surface extending from the opening end of the first opening 31 toward the opening end of the second opening 32 is formed to be composed of an inclined surface extending from the first opening 31 and a cylindrical portion connected to the inclined surface. In Fig. 5B, the surface extending from the opening end of the first opening 31 toward the opening end of the second opening 32 is formed to be composed only of an inclined surface.

[0079] Furthermore, as shown in FIG. 3, in the above-described embodiment, the injection unit 13 has a configuration in which the first opening 31 is disposed at the center of the housing 35 and the second opening 32 is annular (ring-shaped) and surrounds the first opening 31, but the arrangement of the first opening and the second opening of the injection unit is not limited to this configuration.

[0080] 6A, the ejection unit 41 may have a circular first opening 42 for ejecting the first fluid containing water vapor and a second opening 43 for ejecting the second fluid, which are formed adjacent to each other. In this configuration, the structure of the ejection unit 41 can be simplified, and the high-speed nano-droplet generating device can be constructed at low cost.

[0081] Furthermore, for example, as shown in FIG. 6B , the injection unit 44 may be configured to have a circular first opening 45 that ejects a first fluid containing water vapor, and a plurality of circular second openings 46 that eject a second fluid, surrounding the first opening 45.

[0082] Furthermore, for example, as shown in FIG. 6C , the injection unit 47 may be configured such that two circular first openings 48 for ejecting the first fluid containing water vapor are arranged in the vertical direction in the figure, and two circular second openings 49 for ejecting the second fluid are arranged in the horizontal direction in the figure so as to intersect with the two first openings 48.

[0083] In order to obtain the ejection units 41, 44, and 47 shown in Figures 6A to 6C, the inside of the housing 35 may be made into a double-pipe structure, and the shape of the first opening at the tip of the first flow path 33 that supplies the first fluid may be deformed to become the first opening 42, 45, or 48, and the shape of the second opening at the tip of the second flow path 34 that supplies the second fluid may be deformed to become the second opening 43, 46, or 49.

[0084] In the first fluid supply section 11 constituting the high-speed nanodroplet generating device 10 of the first embodiment described above, water vapor is generated by heating the water W in the water tank 21 using the heater 22, but the means for generating water vapor is not limited to a configuration that heats water.

[0085] Second Embodiment FIG. 7 is a schematic diagram showing the configuration of a first fluid supply unit in a high-speed nano-droplet generating device according to a second embodiment of the present invention.

[0086] The first fluid supply unit 51 constituting the high-speed nanodroplet generating device of this embodiment includes a water tank 52, an ultrasonic vibrator 53 arranged at the bottom of the water tank 52, a pressurized gas supply device 54 that supplies pressurized gas toward the water tank 52, a steam supply pipe 56 having a venturi 55, and a high-temperature gas supply device 57 that supplies high-temperature gas to the steam supply pipe 56.

[0087] The water W in the water tank 52 is kept at room temperature, and ultrasonic vibrations are applied by the operation of the ultrasonic vibrator 53, generating microdroplets Ws of water. These microdroplets Ws serve as a water vapor source that mixes with the high-temperature gas HG to become water vapor. The microdroplets Ws are mixed with pressurized gas, such as air, supplied from a pressurized gas supply device 54. The pressurized gas supply device 54 can supply any gas at any pressure and flow rate, and may be equipped with a valve or the like to stop the flow.

[0088] Meanwhile, the high-temperature gas HG supplied from the high-temperature gas supply device 57 to the steam supply pipe 56 has its flow velocity increased by the venturi 55, which is a narrowed portion formed in the steam supply pipe 56, and this high flow velocity causes the microdroplets Ws mixed with the pressurized gas in the water tank 52 to be sucked out. As a result, the microdroplets Ws mix with the high-temperature gas HG and vaporize to become steam. Then, a steam-containing gas R11, which is a first fluid containing steam, is formed.

[0089] In this embodiment, all of the sucked-up microdroplets Ws can be converted into water vapor by controlling the pipe diameter, pipe length, and pipe temperature from the venturi 55 to the end of the water vapor supply pipe 56. Furthermore, if the microdroplets Ws are not supplied sufficiently from the venturi 55, a sufficient amount of water vapor can be generated by adjusting the gas pressure of the pressurized gas supplied to the water tank 52 and the output of the ultrasonic vibrator 53. Furthermore, by adjusting the operating conditions of the ultrasonic vibrator 53, the particle size of the microdroplets Ws can be made smaller.

[0090] [Modification of Second Embodiment] In the first fluid supply unit 51 of the second embodiment described above, the piping connecting the water tank 52 and the venturi 55 of the steam supply pipe 56 may be made of a heat-resistant pipe, and a heating device or the like may be disposed around the heat-resistant pipe to heat it. Note that the material of the heat-resistant pipe is not particularly limited, and may be, for example, a quartz pipe, a metal pipe, or a resin pipe made of a heat-resistant resin (such as Teflon (registered trademark)).

[0091] In this configuration, the water microdroplets Ws are vaporized into steam by the heated heat-resistant tube and then supplied to the venturi 55. In this configuration, the high-temperature gas HG supplied to the steam supply pipe 56 does not need to vaporize the water microdroplets Ws, so the temperature of the high-temperature gas HG can be further lowered.

[0092] It is also preferable to form an ejector in the steam supply pipe 56 instead of the venturi 55, which is a narrowed portion formed in the steam supply pipe 56. Such an ejector generates a low-pressure space by, for example, ejecting high-pressure gas, which serves as a driving source, at high speed. The generated low-pressure space then makes it possible to draw water microdroplets Ws and steam into the steam supply pipe 56.

[0093] 8 is a schematic diagram showing the configuration of a first fluid supply unit in a high-speed nano-droplet generation device according to a third embodiment of the present invention. The first fluid supply unit 61 constituting the high-speed nano-droplet generation device of this embodiment includes a droplet tank 62, a pressurized water supply device 63 that supplies pressurized water to the droplet tank 62, a gas supply device 69 that supplies gas to the droplet tank 62, an atomizer (spray device) 64 formed at one end of a pipe connecting the pressurized water supply device 63 and the droplet tank 62, a steam supply pipe 65, a high-temperature gas supply device 66 that supplies high-temperature gas to the steam supply pipe 65, a heat-resistant pipe 67 that connects the droplet tank 62 and the steam supply pipe 65, and a heating device 68 that heats the heat-resistant pipe 67 from the outside.

[0094] In this embodiment, the first fluid supply unit 61 mixes pressurized water supplied from the pressurized water supply device 63 with gas supplied from the gas supply device 69. The water is then converted into water droplets Ws by the atomizer (spray device) 64 and supplied to the droplet tank 62. The water droplets Ws are then sucked from the droplet tank 62 toward the water vapor supply pipe 65. The water droplets Ws are vaporized as they pass through a heat-resistant tube 67 heated by a heating device 68, becoming water vapor WG. The water vapor is then mixed with the high-temperature gas HG supplied to the water vapor supply pipe 65 to form a water vapor-containing gas R11, which is a first fluid containing water vapor. The pressure of the gas supplied from the gas supply device 69 may be atmospheric pressure or a pressure higher than atmospheric pressure. The gas supply device 69 can set any gas to be supplied at any pressure and flow rate, and may include a valve or the like for stopping the flow.

[0095] In such an embodiment, the water may be poured along the inner wall of the heat-resistant tube and evaporated before reaching the end of the heat-resistant tube to generate steam, or a heated inner tube may be placed inside the heat-resistant tube to evaporate water or tiny water droplets to generate steam.

[0096] 9 is a schematic diagram showing the configuration of a high-speed nano-droplet generating device according to a fourth embodiment of the present invention. The high-speed nano-droplet generating device 100 of this embodiment includes an ejection unit 13 that ejects high-speed nano-droplets M, a fluid supply unit 70 that supplies a first fluid R1 and a second fluid R2 containing water vapor toward the ejection unit 13, and a control unit 14. The high-speed nano-droplets M contain the first fluid R1 and the second fluid R2. In the fourth embodiment, the same components as those in the first embodiment are designated by the same reference numerals, and their description will be omitted.

[0097] (Fluid supply unit) The fluid supply unit 70 includes a first supply mechanism that supplies a fluid containing water vapor that constitutes the first fluid R1, which in this embodiment is water vapor, a second supply mechanism that supplies a gas that constitutes the second fluid R2, which in this embodiment is air, and a gas source 26 that distributes and supplies unheated pressurized gas to the first supply mechanism and the second supply mechanism.

[0098] (Gas Source) In this embodiment, an unheated gas, such as air, oxygen, nitrogen, or carbon dioxide, is supplied from the gas source 26 to the nozzle 74, and the unheated gas R3 is then distributed into a gas R4 used as the first fluid R1 and a second fluid R2. The unheated gas R3 may be distributed by using the nozzle 74 as an annular nozzle to distribute the unheated gas R3 into gas R4 and the second fluid R2, or by providing a distribution pipe (not shown) downstream of the nozzle 74 to distribute the unheated gas R3 into gas R4 and the second fluid R2. Furthermore, a pressure adjustment valve (not shown) may be provided downstream of the nozzle 74 to adjust the supply pressures of the gas R4 and the second fluid R2.

[0099] The gas source 26 may be, for example, a high-pressure gas cylinder, etc. Such a high-pressure gas cylinder can supply air, which is the unheated gas R3, at a supply pressure exceeding 1 atmosphere.

[0100] When the gas constituting the non-heated gas R3 is air, the gas source can be constituted by a pump capable of taking in air from the atmosphere and delivering it at a pressure exceeding 1 atmosphere (0.1 MPa) instead of a high-pressure gas cylinder. The upper limit of the supply pressure of the high-pressure gas is not particularly limited, but may be 1.1 MPa (absolute pressure).

[0101] In this embodiment, air is used as the non-heated gas R3, but other gases such as oxygen, nitrogen, and carbon dioxide can also be used that impart a specific chemical action to the generated high-velocity nanodroplets M. In this case, a high-pressure gas cylinder containing a specific gas at high pressure can be used as the gas source 26.

[0102] (First Supply Mechanism) The first supply mechanism for supplying the water vapor-containing fluid constituting the first fluid R1 (water vapor in this embodiment) includes a water tank 21 for storing water W, a heater 22 serving as water heating means for heating the water W in the water tank 21 to generate water vapor, and a water vapor supply pipe 23. The first fluid supply unit 11 also includes a gas supply device 25A for supplying pressurized gas R4 toward the water tank 21. In this embodiment, the gas R4 supplied from a gas source 26 via a nozzle 74 is supplied to the gas supply device 25A, where it is pressurized, and the pressurized gas R4 is supplied toward the water tank. The pressurized gas R4 supplied from the gas supply device 25A may be heated by a heater 72 provided in a gas supply pipe 71 and then supplied toward the water tank 21.

[0103] The water in the water tank 21 is boiled by the heater 22, and a pressurized gas (first fluid: hereinafter referred to as the water vapor-containing gas) R1 containing water vapor at, for example, 130°C or higher and 160°C or lower is generated and supplied to the injection section 13 described later.

[0104] The pressurized gas R4 supplied from the gas supply device 25A is heated by the heater 72, and the pressurized gas R4 heated to, for example, about 100°C is sent toward the water tank 21, where it is mixed with the water vapor generated by boiling the water W in the water tank 21 to produce a water vapor-containing gas. Such a gas supply device 25A may be composed of, for example, a cylinder for supplying pressurized air and a heater for heating the air. Furthermore, the pressurized gas R1 (also referred to as the first fluid or water vapor-containing gas) supplied from the water tank 21 may be heated by the heater 23A provided in the water vapor supply pipe 23 when it is supplied to the first flow path 33 of the injection unit 13 via the water vapor supply pipe 23.

[0105] (Second supply mechanism) The second supply mechanism supplies the gas that constitutes the second fluid R2, which in this embodiment is air, and has a gas supply pipe that supplies the second fluid R2, which is supplied from the gas source 26 via the nozzle 74, to the injection section 13.

[0106] The second fluid R2 may include any type of gas, mixed gas, or mixture of any solid (powder) or any particulate liquid, such as a supply gas such as air alone, a gas obtained by mixing a substance other than the supply gas with the supply gas, a gas obtained by mixing a supply gas with a particulate solid (powder) or particulate liquid, or a gas obtained by mixing a substance other than the supply gas with the supply gas and further mixing the same with a particulate solid (powder) or particulate liquid.

[0107] In the second supply mechanism, a pressure adjustment valve (not shown) may be provided in the gas supply pipe that supplies the second fluid R2 to the ejection unit 13, and it is preferable to precisely adjust the supply pressure of the second fluid R2 supplied from the gas source 26. The pressure adjustment valve may be composed of, for example, a gas valve or a gas flow meter. Note that such a pressure adjustment valve does not necessarily have to be provided in the distribution pipe as long as the supply pressure of the second fluid R2 can be precisely adjusted.

[0108] In the second supply mechanism, a heater (not shown) may be provided in a part of the gas supply pipe that supplies the second fluid R2 to the injection part 13. The heater heats the second fluid R2 supplied from the gas source 26 through the nozzle 74 to a temperature equal to or higher than room temperature. The gas heating device 28 shown in FIG. 1 may be used as the heater.

[0109] Such a heater heats the temperature of the second fluid R2 to above room temperature, for example, to a temperature of about 30°C to 180°C, and supplies the heated air (second fluid: hereinafter referred to as jet gas) R2 to the injection section 13 described later.

[0110] (Ejection Unit) As in the first embodiment, the ejection unit 13 ejects high-speed nano-droplets M containing the first fluid R1 and the second fluid R2, which are supplied from the first fluid supply unit 11 and the second fluid supply unit 12, respectively, toward the ejection target surface S. In this embodiment, it is preferable to use the same ejection unit 13 as in the first embodiment to eject high-speed nano-droplets M containing the first fluid R1 and the second fluid R2 toward the ejection target surface S.

[0111] (Control Unit) The control unit 14 performs temperature settings and flow rate settings for the nozzle 74 connected to the gas source 26, the gas supply device 25A and heater 22 of the first supply mechanism, and the pressure adjustment valve (not shown) and heater (not shown) of the second supply mechanism, and independently controls the flow rate, temperature, etc. of the water vapor-containing gas (first fluid) R1 sprayed from the first opening 31 of the spray unit 13 and the jet gas (second fluid) R2 sprayed from the second opening 32. The control unit 14 may also control the distribution amount of a distribution pipe (not shown) provided downstream of the nozzle 27.

[0112] The control unit 14 may be configured with a PID (Proportional-Integral-Differential) temperature control device, etc., as in the first embodiment. The control unit 14 may also be configured with a microcomputer equipped with a CPU, memory, etc., and an interface for connecting with each device.

[0113] Next, the operation and function of the high-speed nano-droplet generating device 100 of this embodiment configured as described above will be described. When using the high-speed nano-droplet generating device 100 of this embodiment to generate and spray high-speed nano-droplets, which are groups of droplets with a particle size of 1 nm to 1000 nm and flying at a speed of 1 m / s to 1000 m / s, the control unit 14 is first operated to set the flow rate and pressure of the unheated gas R3 supplied from the nozzle 74, the flow rates and respective supply pressures of the gas R4 and second fluid R2 distributed from the unheated gas R3, the flow rate of the gas R4 supplied from the gas supply device 25A of the first supply mechanism, the set temperature of the heater 72 provided in the gas supply pipe 71, the set temperature of the heater 22 of the first fluid supply unit (the temperature of the water in the water tank 21), and the set temperature of the heater provided in a part of the gas supply pipe that supplies the second fluid R2 of the second supply mechanism to the spray unit 13. This sets the temperature and flow rate of the water vapor-containing gas (first fluid) R1 and the temperature and flow rate of the jet gas (second fluid) R2.

[0114] Then, when spraying is started from the high-speed nanodroplet generating device 100, a water vapor-containing gas (first fluid) R1 is sprayed from the first opening 31 of the spray section 13, and a jet gas (second fluid) R2 is sprayed from the second opening 32 independently of each other toward the spray target surface (spray target) S in the spray direction L.

[0115] When the water vapor-containing gas R1 and the jet gas R2 are sprayed from the spray section 13, the first flow path 33 of the spray section 13 has a tapered shape in which the cross-sectional area becomes smaller as it approaches the first opening 31 in the spray direction L inside the housing 35, so that the water vapor-containing gas R1 does not expand inside the spray section 13 and the temperature does not drop.

[0116] Similarly, the second flow path 34 has a tapered shape in which the cross-sectional area becomes smaller as it approaches the second opening 32 in the injection direction L inside the housing 35, so that the expansion of the jet gas R2 does not occur inside the injection section 13 and the temperature does not decrease.

[0117] Therefore, the water vapor-containing gas R1 and the jet gas R2 are cooled after being ejected to the outside from the first opening 31 and the second opening 32. Therefore, the set ejection temperatures of the water vapor-containing gas R1 and the jet gas R2 hardly change until the water vapor-containing gas R1 and the jet gas R2 reach the first opening 31 and the second opening 32, respectively.

[0118] As in the first embodiment, the opening end of the second opening 32 is shaped to protrude further in the injection direction L than the opening end of the first opening 31, thereby narrowing the region where a circulating flow is generated outside the first opening 31, as shown in Figures 4, 5A, and 5B. Since the second opening 32 that ejects the jet gas R2 protrudes further in the injection direction L than the first opening 31, the temperature of the second flow path 34 is high, and this heat can heat the tip side of the injection part 13.

[0119] Furthermore, a circulating flow is formed at the tip end of the heated injection part 13 by the injection of the water vapor-containing gas R1 from the first opening 31, so that the high-temperature jet gas R2 can always flow from the tip end of the injection part 13. This makes it possible to prevent condensation on the tip end of the injection part 13 where the first opening 31 and the second opening 32 are formed.

[0120] Furthermore, by setting the temperature of the jet gas R2 at the second opening 32 higher than that of the water vapor-containing gas R1 at the first opening 31, for example, by 5°C or more, it is possible to prevent condensation from occurring near the first opening 31, where it is difficult to install a heater. This prevents liquefied water droplets (water droplets) from mixing with the water vapor-containing gas R1, and the water vapor-containing gas R1 jetted from the first opening 31 is entirely composed of vaporized water (water vapor) and air.

[0121] In this way, the water vapor-containing gas R1 from the first opening 31 of the injection section 13 is sprayed by the jet gas R2 from the second opening 32, and the distance over which the gas flies in the injection direction L while maintaining a specific functionality, such as a cleaning effect, i.e., the injection distance F, is significantly extended compared to when the water vapor-containing gas R1 is sprayed alone.

[0122] For example, when the water vapor-containing gas R1 is sprayed alone under the same spray conditions, the spray distance is less than 5 mm, whereas by spraying the jet gas R2 independently in the vicinity of the water vapor-containing gas R1, the spray distance of the high-speed nanodroplets M while maintaining the cleaning effect can be extended to several tens of mm, for example, about 40 mm.

[0123] Furthermore, at the target surface S, which is the surface reached by the high-speed nanodroplets M that maintain this cleaning effect, the cleaning effect is maintained even if the supply amount of water vapor-containing gas R1 is reduced, so the target surface S is prevented from wetting with liquefied water and the target surface S is kept dry.

[0124] As described above, according to the high-speed nano-droplet generating device 100 of this embodiment, by spraying a water vapor-containing gas (first fluid) R1 from the first opening 31 and spraying a jet gas (second fluid) R2 from the second opening 32, it is possible to extend the spray distance of high-speed nano-droplets M having specific functionality, such as a cleaning effect or a sterilization effect, prevent condensation (wetting) on ​​the target surface S due to the spraying of the high-speed nano-droplets M, and further enable the temperature of the high-speed nano-droplets M to be lowered.

[0125] The first fluid of the high-speed nanodroplet generating device 100 of this embodiment is composed of water vapor and air, but the first fluid may be any gas that contains at least water vapor, for example, water vapor alone, water vapor and nitrogen gas, water vapor and oxygen gas, etc.

[0126] As in the first embodiment, the second fluid may contain at least one of a gas, a liquid other than water, and a particulate solid. For example, the second fluid may preferably contain air and a disinfectant powder as a particulate solid.

[0127] [Fifth Embodiment] In the first embodiment, high-speed nano-droplet M is sprayed using the high-speed nano-droplet generating device 10 shown in Fig. 1, but an embodiment in which the second fluid R is an unheated fluid can also be considered in the high-speed nano-droplet generating device 10. In this embodiment, an embodiment in which the second fluid R is an unheated fluid will be described.

[0128] First, in the high-speed nano-droplet generating device 10 shown in FIG. 1, the second fluid R2 supplied from the gas source 26 via the pressure adjusting valve 27 may be supplied directly to the injection section 13 without using the gas heating device 28.

[0129] In this embodiment, except that the second fluid R is supplied to the injection section 13 as an unheated fluid, high-speed nano-droplets M containing the first fluid R1 and the second fluid R2 supplied from the first fluid supply section 11 and the second fluid supply section 12, which are independent of each other, of the injection section 13, can be injected toward the injection target surface S using the same device and method as in the first embodiment.

[0130] In this embodiment, the diameter of the first opening 31 of the injection portion 13 is preferably, for example, about 0.5 mm to 1.0 mm. In this case, the radial width of the second opening 32 may be, for example, about 0.2 mm to 0.6 mm, and the distance between the outer periphery of the first opening 31 and the inner periphery of the second opening 32 may be, for example, about 0.35 mm to 1.0 mm.

[0131] According to this embodiment, the supply pressure of the first fluid R1 can be increased to improve the cleaning power of the high-speed nano-droplets M. In particular, if the supply pressure of the first fluid R1 can be set to about 1.1 MPa (absolute pressure), the injection distance of the high-speed nano-droplets can be further extended and their speed can be accelerated, thereby achieving favorable cleaning power.

[0132] 9 is used to spray high-speed nano-droplets M, but an embodiment in which the second fluid R is an unheated fluid can also be considered in the high-speed nano-droplet generating device 100. In this embodiment, an embodiment in which the second fluid R is an unheated fluid will be described.

[0133] First, in the high-speed nano-droplet generating device 100 shown in FIG. 9, the second fluid R2 supplied from the gas source 26 through the nozzle 74 may be supplied directly to the injection unit 13 without using a heater (not shown).

[0134] In this embodiment, except that the second fluid R is supplied to the injection section 13 as an unheated fluid, high-speed nano-droplets M containing the first fluid R1 and the second fluid R2 supplied respectively from the first fluid supply section 11 and the second fluid supply section 12 of the injection section 13, can be injected toward the injection target surface S using the same device and method as in the fourth embodiment.

[0135] In this embodiment, the diameter of the first opening 31 of the injection portion 13 is preferably, for example, about 0.5 mm to 1.0 mm. In this case, the radial width of the second opening 32 may be, for example, about 0.2 mm to 0.6 mm, and the distance between the outer periphery of the first opening 31 and the inner periphery of the second opening 32 may be, for example, about 0.35 mm to 1.0 mm.

[0136] According to this embodiment, the supply pressure of the first fluid R1 can be increased to improve the cleaning power of the high-speed nano-droplets M. In particular, if the supply pressure of the first fluid R1 can be set to about 1.1 MPa (absolute pressure), the injection distance of the high-speed nano-droplets can be further extended and their speed can be accelerated, thereby achieving favorable cleaning power.

[0137] Although one embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. This embodiment can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as the inventions described in the claims and their equivalents.

[0138] 1, water in a water tank 21 forming a water vapor-containing gas (first fluid) R1 was heated to a temperature of 170°C in the first flow path 33, and air was used as the jet gas (second fluid) R2, with the temperature of the second flow path 34 set to 145°C and the supply pressure (absolute pressure) set to 0.5 MPa. High-speed nanodroplets M consisting of the first fluid and the second fluid were sprayed onto a target surface located 35 mm away from the tip of the spray part 13. As a result, a cleaning indicator previously provided on the target surface was cleaned, and the target surface was dry without getting wet at the end of spraying.

[0139] (Comparative Example) The second fluid supply section 12 was removed from the high-speed nanodroplet generating device 10 as shown in Figure 1, and only the water vapor-containing gas (first fluid) R1 was sprayed to clean the cleaning indicator that had been previously installed on the spray target surface, but the cleaning indicator was not cleaned.

[0140] In addition, the target surface was moved to a position 5 mm away from the tip of the spray portion 13, and only the water vapor-containing gas (first fluid) R1 was sprayed in the same manner, but even in this case the cleaning indicator was not cleaned, and the target surface was wet with condensed water from the water vapor.

[0141] From the above results, it has been confirmed that, as in this embodiment, by providing a first fluid supply unit that supplies a first fluid containing water vapor toward the injection unit and a second fluid supply unit that supplies a second fluid at a supply pressure exceeding 1 atmosphere toward the injection unit, and by ejecting the first fluid from the first opening of the injection unit and the second fluid from the second opening, it is possible to realize a high-speed nano-droplet generating device that can extend the injection distance while maintaining the functionality of the high-speed nano-droplets and prevent condensation (wetting) of the injection target due to the injection of high-speed nano-droplets.

[0142] The high-speed nanodroplet generating device of the present invention can spray high-speed nanodroplets having specific functionality, such as cleaning or sterilizing effects, at a practical spray distance while preventing the sprayed object from getting wet and achieving low temperatures, thereby realizing a safe cleaning device or sterilization device without using chemicals, etc. Therefore, it has industrial applicability.

[0143] REFERENCE SIGNS LIST 10... High-speed nano-droplet generating device 11... First fluid supply section 12... Second fluid supply section 13... Injection section 31... First opening 32... Second opening 33... First flow path 34... Second flow path M... High-speed nano-droplet R1... First fluid R2... Second fluid

Claims

1. A high-speed nanodroplet generating device that generates high-speed nanodroplets, which are groups of droplets with a particle size of 1 to 1000 nm and flying at a speed of 1 to 1000 m / s, comprising: an ejection unit that ejects high-speed nanodroplets containing a first fluid and a second fluid; a first fluid supply unit that supplies the first fluid containing water vapor toward the ejection unit; and a second fluid supply unit that supplies the second fluid toward the ejection unit at a supply pressure exceeding 1 atmosphere, wherein the ejection unit has a first opening for ejecting the first fluid and a second opening for ejecting the second fluid.

2. A high-speed nanodroplet generating device as described in claim 1, wherein the second opening is annularly opened so as to surround the first opening when viewed in a plan view from the direction of ejection of the high-speed nanodroplets.

3. A high-speed nano-droplet generating device as described in claim 2, wherein the opening end of the second opening is formed downstream of the opening end of the first opening along the injection direction of the high-speed nano-droplets.

4. A high-speed nano-droplet generating device according to any one of claims 1 to 3, wherein the second fluid includes at least one of a gas, a liquid other than water, and a particulate solid.

5. The high-speed nano-droplet generating device according to claim 4, wherein the second fluid supply section further comprises a powder supply section that supplies powder, which is the fine particle solid.

6. A high-speed nanodroplet generating device as described in any one of claims 1 to 3, wherein the first fluid supply unit has a water tank for storing water and a water heating means for heating the water in the water tank to generate water vapor.

7. A high-speed nanodroplet generating device as described in any one of claims 1 to 3, wherein the first fluid supply unit comprises a water tank for storing water, and an ultrasonic vibrator for applying ultrasonic waves to the water in the water tank to generate minute droplets of water that serve as a source of water vapor.

8. A high-speed nanodroplet generating device as described in claim 6, wherein the second fluid supply unit has a gas heating means for heating gas, and the water heating means and the gas heating means can be individually and independently controlled in temperature.

9. A high-speed nanodroplet generating device according to any one of claims 1 to 3, wherein the temperature of the second fluid at the second opening is higher than the temperature of the first fluid at the first opening.

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