Sterilization device for fluid

Abstract

To provide a sterilization device for fluid which is improved in sterilization efficiency of fluid.SOLUTION: A sterilization device for fluid 1 includes: a sterilization portion 10 which is formed of a member having transmissivity of ultraviolet light, and in which a chamber inflow port 12 which has a sterilization chamber 60 through which fluid sterilized by ultraviolet light flows, and flows the fluid into the sterilization chamber 60, and a chamber outflow port 13 through which the fluid flows from the sterilization chamber 60 are opened; and a light source portion 20 for irradiating the fluid of the sterilization chamber 60 with ultraviolet light, from one end side of the sterilization chamber 60, wherein the chamber inflow port 12 and the chamber outflow port 13 are opened in such a way as to face the light source portion 20 on the other end side of the sterilization chamber 60, and the opening area of the chamber inflow port 12 is smaller than the opening area of the chamber outflow port 13.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a fluid sterilization device. [Background technology]

[0002] Patent Document 1 discloses a conventional flowing water sterilization device that sterilizes a fluid by irradiating it with ultraviolet light. This conventional sterilization device includes an irradiation chamber and a UV radiation source. The irradiation chamber has an internal space through which the fluid to be sterilized flows. The irradiation chamber is provided with an inlet port for allowing the flowing water to flow into the internal space and an outlet port for allowing the flowing water to flow out of the internal space. The UV radiation source irradiates ultraviolet light toward the internal space. The flowing water flowing through the internal space is sterilized by the ultraviolet light irradiated from the UV radiation source. The inlet port and outlet port are arranged adjacent to each other in the irradiation chamber. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2020-530384 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-described conventional technology, the inlet port and the outlet port are arranged adjacent to each other in the irradiation chamber, so that the fluid that flows into the internal space of the irradiation chamber from the inlet port is likely to flow out from the adjacent outlet port, which shortens the time that the fluid stays in the internal space of the irradiation chamber, making it difficult to improve the sterilization efficiency.

[0005] The present invention has been made in view of the above background, and aims to provide a fluid sterilizing device that improves the efficiency of sterilizing fluids. [Means for solving the problem]

[0006] One aspect of the present invention is A fluid sterilization device that sterilizes a fluid by irradiating the fluid with ultraviolet light, a sterilization unit that forms a sterilization chamber through which the fluid to be sterilized by the ultraviolet light flows, has a chamber inlet for allowing the fluid to flow into the sterilization chamber and a chamber outlet for allowing the fluid to flow out of the sterilization chamber, and is made of a material that is transparent to the ultraviolet light; a light source unit that irradiates the fluid in the sterilization chamber with the ultraviolet light from one end side of the sterilization chamber, the chamber inlet and the chamber outlet open at the other end of the sterilization chamber so as to face the light source unit, In the fluid sterilization device, the chamber inlet has an opening area that is smaller than the opening area of ​​the chamber outlet. [Effects of the Invention]

[0007] In the above aspect, the opening area of ​​the chamber inlet is smaller than the opening area of ​​the chamber outlet, which allows the flow rate and dynamic pressure of the fluid flowing into the sterilization chamber from the chamber inlet to be higher than when the opening area of ​​the chamber inlet is equal to or larger than the opening area of ​​the chamber outlet. Because the chamber inlet opens facing the light source, the flow rate and dynamic pressure of the fluid flowing into the sterilization chamber from the chamber inlet are higher, which makes it easier for the fluid flowing into the sterilization chamber from the chamber inlet to reach the vicinity of the light source. This increases the amount of time the fluid stays in the sterilization chamber, thereby improving the sterilization efficiency of the fluid. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing the configuration of a fluid sterilization device according to an embodiment. [Figure 2] 1 is a perspective view showing the appearance of a fluid sterilization device according to an embodiment. [Figure 3] 1 is a perspective view showing the appearance of a fluid sterilization device according to an embodiment. [Figure 4] 1 is a perspective view showing the appearance of a fluid sterilization device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] The fluid sterilization device is a fluid sterilization device that irradiates a fluid with ultraviolet light to sterilize the fluid, and comprises: a sterilization chamber formed so that the fluid to be sterilized by the ultraviolet light flows; a sterilization section formed of a material that is transparent to ultraviolet light, which has a chamber inlet for allowing the fluid to flow into the sterilization chamber and a chamber outlet for allowing the fluid to flow out of the sterilization chamber; and a light source section that irradiates the fluid in the sterilization chamber with ultraviolet light from one end side of the sterilization chamber, the chamber inlet and the chamber outlet opening at the other end side of the sterilization chamber so as to face the light source section, and the opening area of ​​the chamber inlet is smaller than the opening area of ​​the chamber outlet.

[0010] In the fluid sterilization device, a plurality of chamber inlets may be provided in the sterilization chamber, and the opening area of ​​each of the chamber inlets may be smaller than the opening area of ​​the chamber outlet. This allows the flow velocity and dynamic pressure of the fluid to be increased at all of the plurality of chamber inlets.

[0011] The difference in the opening areas of the plurality of chamber inlets may be 10% or less. This allows the fluid to flow into the sterilization chamber as evenly as possible from the plurality of chamber inlets. This makes it easier for the fluid that has flowed into the sterilization chamber from the plurality of chamber inlets to reach the vicinity of the light source.

[0012] The sterilization unit may have an auxiliary inlet, which allows the fluid to flow into the sterilization chamber, opening in a direction different from that of the inlet, at a location closer to the light source than the inlet. This allows a fluid flow in a direction different from that of the fluid flowing in from the inlet near the light source, thereby preventing fluid from accumulating in areas near the light source that are blind spots for ultraviolet light. This allows the fluid to be effectively irradiated with ultraviolet light, further improving sterilization efficiency.

[0013] The sum of the opening areas of the chamber inlet and the auxiliary inlet may be larger than the opening area of ​​the chamber outlet, so that even if turbulence occurs in the sterilization chamber due to fluid flowing in not only through the chamber inlet but also through the auxiliary inlet, an increase in fluid pressure loss in the sterilization chamber can be suppressed.

[0014] The chamber inlet may have a plurality of openings into the sterilization chamber, the auxiliary inlet may have a plurality of openings into the sterilization chamber, and the total opening area of ​​the plurality of auxiliary inlets may be smaller than the total opening area of ​​the plurality of chamber inlets. This can prevent the flow rate of the fluid flowing in from the auxiliary inlets from becoming excessive and the flow rate of the fluid flowing in from the chamber inlet from becoming insufficient.

[0015] For example, the total opening area of ​​the plurality of auxiliary inlets may be 50% or less of the total opening area of ​​the plurality of chamber inlets.

[0016] The opening area of ​​each of the auxiliary inlets may be smaller than the opening area of ​​each of the chamber inlets, thereby effectively preventing an excessive flow rate of the fluid flowing in through the auxiliary inlets and an insufficient flow rate of the fluid flowing in through the chamber inlets.

[0017] For example, the opening area of ​​each of the auxiliary inlets may be 25% or less of the opening area of ​​each of the chamber inlets.

[0018] The sterilization chamber may further include a housing that houses the sterilization unit and the light source unit and has a housing supply port formed therein through which the fluid is supplied, the housing being configured so that the fluid flows from the housing supply port to the chamber inlet, and the difference in opening area between the housing supply port, the chamber inlet, and the chamber outlet may be 10% or less. Even if the opening area of ​​the chamber inlet is made smaller than the opening area of ​​the chamber outlet so that the fluid that has flowed into the sterilization chamber from the chamber inlet can easily reach the vicinity of the light source unit, an increase in pressure loss of the fluid in the sterilization unit can be suppressed.

[0019] The sterilization unit may be formed in a cylindrical shape with a bottom, the light source unit may be arranged to irradiate the ultraviolet light from an opening side of the sterilization unit toward the interior of the sterilization unit, the chamber inlet and the chamber outlet may be formed on a bottom surface of the sterilization unit, and the auxiliary inlet may be formed on a portion of the cylindrical surface of the sterilization unit closer to the light source unit. By appropriately arranging the chamber inlet and the auxiliary inlet, the above-mentioned effects can be effectively achieved.

[0020] In the fluid sterilization device, the inner surface of the sterilization unit that forms the sterilization chamber may be made of a material with a reflectance of 50% or less to ultraviolet light. In this case, since the reflectance to ultraviolet light is 50% or less, the illuminance of ultraviolet light in areas of the sterilization chamber far from the light source is low. However, the chamber inlet and auxiliary inlet make it easier for the fluid to reach areas close to the light source (i.e., areas with high illuminance of ultraviolet light). Therefore, high sterilization efficiency can be ensured.

[0021] (Embodiment 1) 1. Basic configuration of fluid sterilization device 1 The basic configuration of the fluid sterilization device 1 will be described with reference to Figures 1, 2, 3 and 4. As shown in Figures 1 and 2, the fluid sterilization device 1 mainly comprises a sterilization unit 10 having a sterilization chamber 60, a light source unit 20 that emits ultraviolet light into the sterilization chamber 60, and a housing 30 that houses the sterilization unit 10 and the light source unit 20.

[0022] An outer space 70 is formed between the sterilization unit 10 and the housing 30. The outer space 70 is a space located outside the sterilization unit 10.

[0023] The fluid sterilization device 1 is a device that sterilizes a fluid by flowing the fluid from the outside into the sterilization chamber 60 through the outer space 70 and irradiating the fluid in the sterilization chamber 60 with ultraviolet light from the light source unit 20. The fluid to be sterilized may be a gas or a liquid, and may be a mixture of gas and liquid, a mixture of gas and powdery solid, or the like, as long as it has fluidity. In the case of a liquid, examples include water, oil, alcohol, and solutions using these as solvents.

[0024] The sterilization unit 10 has a sterilization chamber 60 inside. The sterilization chamber 60 is a space where ultraviolet light emitted from the light source unit 20 is irradiated onto the flowing fluid. The wall surface of the sterilization chamber 60 is formed into a concave cylindrical surface. By making the sterilization chamber 60 into a concave cylindrical surface, the ultraviolet light can be efficiently reflected by the concave cylinder, and the illuminance of the ultraviolet light inside the sterilization chamber 60 can be increased, thereby improving the sterilization efficiency of the fluid.

[0025] The sterilization unit 10 is made of a material that reflects ultraviolet light. It is preferable that the sterilization unit 10 is made of a material that has excellent corrosion resistance against the fluid to be sterilized. The sterilization unit 10 is made entirely of, for example, stainless steel. SUS is a material that has a reflectance of about 20 to 30% for the ultraviolet light from the light source unit 20. If the sterilization unit 10 is made of a material that has a high reflectance for the ultraviolet light from the light source unit 20, the reflectance of the ultraviolet light can be increased, and sterilization efficiency can be improved. Examples of materials that have a high reflectance for the ultraviolet light from the light source unit 20 include PTFE (polytetrafluoroethylene) and aluminum. PTFE is a material that has a reflectance of 90% or more for ultraviolet light. Aluminum is a material that has a reflectance of about 70 to 80% for ultraviolet light. When SUS is used as the material for the sterilization unit 10, the sterilization unit 10 can be formed at a lower cost than when PTFE is used as the material for the sterilization unit 10. SUS is a material that absorbs ultraviolet light (in other words, a material with low transmittance of ultraviolet light). If a material that absorbs ultraviolet light (in other words, a material with low transmittance of ultraviolet light) is used as the material for the sterilization unit 10, it is possible to prevent deterioration of the housing 30 due to the influence of ultraviolet light that passes through the sterilization unit 10. The transmittance of ultraviolet light through the material for the sterilization unit 10 is preferably 5% or less. The material that absorbs ultraviolet light (in other words, a material with low transmittance of ultraviolet light) may be a resin containing carbon or rubber containing carbon.

[0026] 1 and 3, the sterilization unit 10 is formed with a light source opening 14 that opens into the sterilization chamber 60. The light source opening 14 is an opening that allows ultraviolet light emitted from the light source unit 20 to enter the sterilization chamber 60.

[0027] As shown in Figures 1 and 4, the sterilization unit 10 is further formed with a chamber inlet 12 that opens into the sterilization chamber 60. The chamber inlet 12 connects the sterilization chamber 60 with the outer space 70. The chamber inlet 12 is an inlet for allowing fluid to flow from the outer space 70 into the sterilization chamber 60. The chamber inlet 12 is formed on the bottom surface of the sterilization unit 10. As shown in Figure 4, the chamber inlet 12 is formed at a position offset from the center on the bottom surface of the sterilization unit 10.

[0028] The sterilization unit 10 is further formed with a chamber outlet 13 that opens into the sterilization chamber 60. The chamber outlet 13 connects the sterilization chamber 60 to the outside. The chamber outlet 13 is an outlet for allowing fluid to flow from the sterilization chamber 60 to the outside. The chamber outlet 13 is formed on the bottom surface of the sterilization unit 10. As shown in Figure 4, the chamber outlet 13 is formed at a position offset from the center on the bottom surface of the sterilization unit 10.

[0029] The sterilization unit 10 is further formed with an auxiliary inlet 15 that opens into the sterilization chamber 60. The auxiliary inlet 15 connects the sterilization chamber 60 with the outer space 70. The auxiliary inlet 15 is an inlet for auxiliary flow of fluid from the outer space 70 into the sterilization chamber 60. The auxiliary inlet 15 is formed in a part of the cylindrical surface of the sterilization unit 10 closer to the light source unit 20.

[0030] As shown in FIG. 1, the light source unit 20 is arranged to close the light source opening 14. The light source unit 20 is configured to emit ultraviolet light from the light source opening 14 into the sterilization chamber 60. The portion of the light source unit 20 exposed to the light source opening 14, i.e., the emission surface 201 of the light source unit 20 that emits ultraviolet light, forms part of the wall surface of the sterilization chamber 60. Therefore, the fluid in the sterilization chamber 60 comes into contact with the emission surface 201 of the light source unit 20. Therefore, the light source unit 20 is cooled by the fluid in the sterilization chamber 60. As a result, the light-emitting efficiency of the light source unit 20 can be improved.

[0031] The housing 30 is provided to enclose the sterilization unit 10 and the light source unit 20. In other words, the housing 30 is arranged to cover the sterilization unit 10 and the light source unit 20. Specifically, the inner surface of the housing 30 faces the outer surface of the sterilization unit 10. The inner surface of the housing 30 also faces the outer surface of the light source unit 20. In other words, the inner surface of the housing 30 faces the outer back surface 202 and outer peripheral surface 203 that form the outer surface of the light source unit 20.

[0032] An outer space 70 is formed by the gap between the inner surface of the housing 30 and the outer surface of the sterilization unit 10, and the gap between the inner surface of the housing 30 and the outer surface of the light source unit 20. A part of the outer space 70 faces the inner surface of the housing 30 and the outer surface of the sterilization unit 10. Another part of the outer space 70 faces the inner surface of the housing 30 and the outer surface of the light source unit 20.

[0033] The housing 30 is formed with a housing supply port 321 through which a fluid is supplied. The housing supply port 321 is in communication with the outer space 70. That is, the fluid supplied from the housing supply port 321 passes through the outer space 70 and flows into the sterilization chamber 60 from the chamber inlet 12.

[0034] The housing 30 is further formed with a housing outlet 311 for discharging the fluid. The housing outlet 311 communicates with the chamber outlet 13 of the sterilization unit 10 via the outer space 70. Therefore, the fluid sterilized in the sterilization chamber 60 is discharged from the housing outlet 311 via the chamber outlet 13 to the outside.

[0035] 2. Fluid flow path in the fluid sterilization device 1 The fluid flow path in the fluid sterilization device 1 will be described with reference to Fig. 1. As shown in Fig. 1, the fluid is supplied from the housing supply port 321 to the outer space 70.

[0036] The fluid supplied from the housing supply port 321 to the outer space 70 first flows into the gap between the inner surface of the housing 30 and the outer back surface 202 of the light source unit 20 in the outer space 70. At this time, the fluid comes into contact with the outer back surface 202 of the light source unit 20 and cools the light source unit 20. Next, the fluid flows into the gap between the inner surface of the housing 30 and the outer peripheral surface 203 of the light source unit 20 in the outer space 70. At this time, the fluid comes into contact with the outer peripheral surface 203 of the light source unit 20 and cools the light source unit 20. Next, the fluid flows into the gap between the inner surface of the housing 30 and the outer surface of the sterilization unit 10 in the outer space 70.

[0037] In this way, the fluid supplied from the housing supply port 321 first comes into contact with the outer rear surface 202 and the outer peripheral surface 203, which are the outer surfaces of the light source unit 20. Therefore, the light source unit 20 is efficiently cooled by the fluid supplied from the housing supply port 321. As a result, the light emission efficiency of the light source unit 20 can be improved.

[0038] Next, the fluid in the outer space 70 flows into the sterilization chamber 60 from the chamber inlet 12 of the sterilization unit 10. Because the chamber inlet 12 opens on the bottom surface of the sterilization unit 10 facing the light source unit 20, the fluid that flows into the sterilization chamber 60 from the chamber inlet 12 flows towards the light source unit 20.

[0039] The fluid in the outer space 70 also flows into the sterilization chamber 60 from the auxiliary inlet 15 of the sterilization unit 10. The auxiliary inlet 15 is formed in a part of the cylindrical surface of the sterilization unit 10 closer to the light source unit 20, so the fluid flowing into the sterilization chamber 60 from the auxiliary inlet 15 creates a fluid flow from the radial outside toward the radial center (the front side of the light source opening 14).

[0040] The fluid that flows into the sterilization chamber 60 from the chamber inlet 12 and the auxiliary inlet 15 changes direction near the light source 20 and proceeds toward the chamber outlet 13. The fluid then flows from the chamber outlet 13 to the housing outlet 311 and is discharged to the outside.

[0041] 3. Components of the Sterilization Unit 10 The components of the sterilization unit 10 will be described with reference to Figures 1, 3 and 4. The sterilization unit 10 is divided into three parts: a first main body component 101, a second main body component 102 and a third main body component 103. The first main body component 101 is cylindrical. The second main body component 102 is disc-shaped and is arranged to close the bottom of the first main body component 101. The third main body component 103 is annular disc-shaped and is arranged to close the top of the first main body component 101.

[0042] The bottom and top of the first body component 101 are sealed with the second body component 102 and the third body component 103, thereby forming a sterilization section 10 having an internal sterilization chamber 60. In this example, the first body component 101, the second body component 102 and the third body component 103 are made of SUS, so the first body component 101 and the second body component 102, and the first body component 101 and the third body component 103 are joined by welding.

[0043] The second main body component 102 is formed with chamber inlets 12 for allowing fluid to flow into the sterilization chamber 60. The chamber inlets 12 are formed at positions offset from the center of the disc-shaped second main body component 102. In this example, a plurality of chamber inlets 12 are formed and are arranged in an arc shape along the outer edge of the disc-shaped second main body component 102. In the example of Figure 3, four chamber inlets 12 are formed, but the number of chamber inlets 12 is not limited to four and may be more or less than four.

[0044] The second body component 102 is formed with a chamber outlet 13 for allowing fluid to flow out of the sterilization chamber 60. The chamber outlet 13 is formed at a position offset from the center of the disk-shaped second body component 102. In this example, one chamber outlet 13 is formed. It is preferable that the chamber inlet 12 is positioned as far away from the chamber outlet 13 as possible on the second body component 102. In the example of Figure 3, the chamber inlet 12 is positioned in the right half region of the second body component 102, and the chamber outlet 13 is positioned in the left half region of the second body component 102.

[0045] The first main body component 101 is formed with auxiliary inlets 15 that allow fluid to auxiliary flow into the sterilization chamber 60. The auxiliary inlets 15 are formed in a portion of the cylindrical first main body component 101 closer to the third main body component 103. In this example, a plurality of auxiliary inlets 15 are formed and are arranged at equal intervals around the circumference of the cylindrical first main body component 101.

[0046] The radiation angle θ shown in Fig. 1 is the radiation angle of the ultraviolet light emitted by the light source unit 20. The radiation angle θ is set depending on the radiation angle of the light emitting element 22 itself of the light source unit 20, the shape of a reflector arranged inside the light source unit 20, etc. The radiation angle θ is the angular range in which the light intensity is more than half of the peak in the angular distribution of the light intensity of the ultraviolet light emitted by the light source unit 20. For example, the radiation angle θ is 90 to 150 degrees.

[0047] Within the sterilization chamber 60, areas outside the radiation angle θ are so-called blind spots, where the ultraviolet light emitted from the light source unit 20 is unlikely to reach. As shown in Figure 1, the auxiliary inlet 15 opens to face the blind spot area for the ultraviolet light.

[0048] The second main body component 102 is fitted into the bottom of the housing 30. A gasket 34 is sandwiched between the bottom of the housing 30 and the second main body component 102. The gasket 34 is disposed on the bottom of the housing 30 and is a sealing member that seals the connection between the chamber outlet 13 of the second main body component 102 and the housing outlet 311 of the housing 30.

[0049] A hole formed in the center of the annular disk-shaped third main body component 103 constitutes the light source opening 14. As shown in Figures 3 and 4, a screw hole 103a is formed near the outer edge of the third main body component 103. The third main body component 103 is fastened and fixed to the housing 30 using the screw hole 103a and a screw (not shown).

[0050] The opening areas of the chamber inlet 12, chamber outlet 13 and auxiliary inlet 15 in the sterilization chamber 60 are as follows: The opening area of ​​each of the multiple chamber inlets 12 is smaller than the opening area of ​​the chamber outlet 13. This allows the flow velocity and dynamic pressure of the fluid at the chamber inlet 12 to be increased.

[0051] The opening area of ​​each chamber inlet 12 is smaller than the opening area of ​​the chamber outlet 13. The difference between the opening areas of the chamber inlets 12 is 10% or less. This allows the fluid to flow into the sterilization chamber 60 from the multiple chamber inlets 12 as evenly as possible.

[0052] The total opening area of ​​the chamber inlet 12 and the auxiliary inlet 15 is larger than the opening area of ​​the chamber outlet 13. This prevents an increase in pressure loss of the fluid in the sterilization chamber 60, even if turbulence occurs in the sterilization chamber 60 due to the fluid flowing in from the chamber inlet 12 and the auxiliary inlet 15.

[0053] The total opening area of ​​the multiple auxiliary inlets 15 is smaller than the total opening area of ​​the multiple chamber inlets 12. Specifically, the total opening area of ​​the multiple auxiliary inlets 15 is 50% or less of the total opening area of ​​the multiple chamber inlets 12. This makes it possible to prevent the flow rate of the fluid flowing in from the auxiliary inlets 15 from becoming excessive and the flow rate of the fluid flowing in from the chamber inlets 12 from becoming insufficient.

[0054] The opening area of ​​each auxiliary inlet 15 is smaller than the opening area of ​​each chamber inlet 12. Specifically, the opening area of ​​each auxiliary inlet 15 is 25% or less of the opening area of ​​each chamber inlet 12. This makes it possible to prevent the flow rate of the fluid flowing in from the auxiliary inlet 15 from becoming excessive and the flow rate of the fluid flowing in from the chamber inlet 12 from becoming insufficient.

[0055] The difference between the opening areas of the housing supply port 321, the chamber inlet 12, and the chamber outlet 13 is 10% or less. This makes it possible to prevent an increase in fluid pressure loss in the sterilization unit 10 even if the opening area of ​​the chamber inlet 12 is smaller than the opening area of ​​the chamber outlet 13.

[0056] 6. Configuration of the light source unit 20 The configuration of the light source unit 20 will be described with reference to Figure 1. The light source unit 20 is positioned so as to cover the light source opening 14 of the sterilization unit 10. The light source unit 20 is also positioned so that the ultraviolet light emission side faces the sterilization chamber 60. The ultraviolet light emitted from the light source unit 20 enters the sterilization chamber 60 through the light source opening 14.

[0057] The light source unit 20 has a substrate 21, a light emitting element 22, a window member 23, and a light source housing 24. The overall shape of the light source unit 20 is, for example, a disk shape. However, the shape of the light source unit 20 may be any shape.

[0058] The substrate 21 is a mounting substrate having a mounting surface. A wiring pattern is formed on the substrate 21. A wiring 80 for supplying power is connected to the rear surface of the substrate 21.

[0059] The light-emitting element 22 is an element that emits ultraviolet light. For example, the light-emitting element 22 uses a group III nitride semiconductor and has an emission wavelength of 200 to 280 nm. Because the emission wavelength is in the UVC region, fluids can be efficiently sterilized. The light-emitting element 22 may be directly mounted on the mounting surface of the substrate 21, or a packaged LED package may be mounted on the mounting surface of the substrate 21. The LED package is a unit in which the light-emitting element 22 is placed in a housing and sealed with a glass plate or a lens. In addition, various elements (for example, Zener diodes) necessary for driving and protecting the light-emitting element 22 are mounted on the mounting surface of the substrate 21.

[0060] The window member 23 is a member that transmits ultraviolet light and is formed in a disk shape. The window member 23 is a glass plate made of quartz. Materials other than quartz may be used as the material of the window member 23 as long as they transmit ultraviolet light. For example, sapphire may be used as the material of the window member 23. Furthermore, the window member 23 is not limited to being plate-shaped, and may be lenticular, such as a TIR lens, a fly's eye lens, or a Fresnel lens.

[0061] The light source housing 24 is provided so as to cover other portions but not to cover at least the vicinity of the center of the window member 23. The light source housing 24 is provided so as to continuously cover, for example, the back surface and side surfaces of the substrate 21 and the side surfaces of the window member 23.

[0062] The outer surface of the light source unit 20 has an emission surface 201 that emits ultraviolet light, an outer back surface 202 located on the back side of the emission surface, and an outer peripheral surface 203. The emission surface 201 is located corresponding to the light source opening 14, and is formed by a portion of the window member 23 that is not covered by the light source housing 24. In other words, the emission surface 201 is formed by the surface of the window member 23. The outer back surface 202 is formed by a portion on the back side of the light source housing 24. The outer peripheral surface 203 is formed by a portion of the outer peripheral surface of the light source housing 24.

[0063] The light source housing 24 has a heat dissipation member 241 that forms the outer rear surface 202 and outer peripheral surface 203 of the light source unit 20. The heat dissipation member 241 is made of a material with high heat dissipation properties. For example, the heat dissipation member 241 is made of a metal such as SUS or Al, or a resin material with high heat dissipation properties. Because the heat dissipation member 241 of the light source unit 20 comes into contact with a fluid, the light source unit 20 can be cooled efficiently.

[0064] The lower end of the heat dissipation member 241 is in thermally conductive contact with the third main body constituent member 103 of the sterilization unit 10. Since the heat of the light source unit 20 can be dissipated to the fluid not only via the heat dissipation member 241 but also via the sterilization unit 10, the light source unit 20 can be cooled even more efficiently.

[0065] 7. Configuration of the housing 30 The configuration of the housing 30 will be described with reference to Figures 1 and 2. As described above, the housing 30 is provided to house the sterilization unit 10 and the light source unit 20. The housing 30 comprises a first housing member 31 and a second housing member 32. A seal structure using a first O-ring 33 is formed at the joint between the first housing member 31 and the second housing member 32.

[0066] The first housing member 31 is configured to cover the outer surface of the sterilization unit 10. A part of the outer space 70 is formed between the inner surface of the first housing member 31 and the outer surface of the sterilization unit 10.

[0067] A housing outlet 311 is formed in the first housing member 31. The housing outlet 311 is connected to the chamber outlet 13 of the sterilization unit 10. A sealing structure using a ring-shaped gasket 34 is formed at the connection between the housing outlet 311 and the chamber outlet 13. The gasket 34 is made of, for example, fluororubber or fluoroelastomer.

[0068] The second housing member 32 is configured to cover the outer surface of the light source unit 20. Therefore, the remaining part of the outer space 70 is formed between the inner surface of the second housing member 32 and the outer surface of the light source unit 20.

[0069] A housing supply port 321 is formed in the second housing member 32. The housing supply port 321 is arranged to face the outer back surface 202 of the light source unit 20. When viewed from the central axis direction of the housing supply port 321, at least a part of the opening of the housing supply port 321 is set to face the outer back surface of the light source unit 20. This allows the fluid that has flowed into the outer space 70 from the housing supply port 321 to directly hit the light source unit 20, thereby improving the cooling efficiency of the light source unit 20.

[0070] In particular, when viewed from the central axis direction of the housing supply port 321, it is preferable that the entire opening of the housing supply port 321 is set to face the outer rear surface 202 of the light source unit 20. This can further improve the cooling efficiency of the light source unit 20.

[0071] 1, the second housing member 32 is provided with a wiring opening 322 for passing wiring 80 connecting the light source unit 20 to the outside. The wiring opening 322 is, for example, cylindrical, and one end of the cylinder is inserted into a back surface opening 204 provided on the outer back surface 202 of the light source unit 20. A gap between the cylindrical wiring opening 322 of the second housing member 32 and the back surface opening 204 provided on the outer back surface 202 of the light source unit 20 is sealed by a second O-ring 81. By passing the wiring 80 through the cylindrical interior of the wiring opening 322, the connection portion between the light source unit 20 and the wiring 80 and the wiring 80 are prevented from coming into contact with the fluid.

[0072] The first housing member 31 and the second housing member 32 are fixed together by a fastening member 36. The fastening member 36 is a ring-shaped member that fits onto the outside of the first housing member 31 and the second housing member 32, and a female thread 361 is formed on the inner peripheral surface of the fastening member 36. A male thread 312 that corresponds to the female thread 361 of the fastening member 36 is formed on the outer peripheral surface of the first housing member 31. A flange 362 that protrudes annularly radially inward is formed on the upper end of the fastening member 36. The flange 362 is an engaging portion that engages with the second housing member 32 in the axial direction.

[0073] When the fastening member 36 is fitted onto the outside of the first housing member 31 and the second housing member 32 and the female thread 361 of the fastening member 36 is fastened to the male thread 312 of the first housing member 31, the flange 362 of the fastening member 36 engages with the second housing member 32 and presses the second housing member 32 against the first housing member 31. This fixes the first housing member 31 and the second housing member 32 together.

[0074] 8. Fluid flow in the sterilization chamber 60 The flow of fluid in the sterilization chamber 60 will be described with reference to Figure 1. As shown in Figure 1, the chamber inlet 12, which allows fluid to flow into the sterilization chamber 60, opens at the bottom surface of the sterilization unit 10, facing the light source unit 20. Therefore, the fluid that flows into the sterilization chamber 60 from the chamber inlet 12 flows towards the light source unit 20.

[0075] Because the opening area of ​​each chamber inlet 12 is smaller than the opening area of ​​each chamber outlet 13, the flow rate and dynamic pressure of the fluid flowing from the chamber inlet 12 into the sterilization chamber 60 can be increased compared to when the opening area of ​​each chamber inlet 12 is equal to the opening area of ​​the chamber outlet 13. This makes it easier for the fluid flowing from the chamber inlet 12 into the sterilization chamber 60 to reach the vicinity of the light source unit 20. Therefore, the fluid can be irradiated with ultraviolet light as close to the light source unit 20 as possible, thereby improving sterilization efficiency.

[0076] The auxiliary inlet 15, which auxiliary introduces fluid into the sterilization chamber 60, is formed in a portion of the cylindrical surface of the sterilization unit 10 closer to the light source unit 20. Therefore, in the region of the sterilization chamber 60 closer to the light source unit 20, a fluid flow is created from the radially outer side toward the radially center side (the front side of the light source opening 14). This creates a fluid flow from the region that is a blind spot for ultraviolet light toward the region in front of the light source opening 14. Therefore, fluid retention in the region that is a blind spot for ultraviolet light is suppressed, and ultraviolet light can be irradiated onto the fluid as close to the front of the light source opening 14 as possible, i.e., within the range of the radiation angle θ of the ultraviolet light, thereby improving sterilization efficiency.

[0077] The fluid that flows into the sterilization chamber 60 from the chamber inlet 12 and the auxiliary inlet 15 changes direction near the light source 20 and proceeds toward the chamber outlet 13. The fluid then flows from the chamber outlet 13 to the housing outlet 311 and is discharged to the outside.

[0078] 9. Summary of Effects of the Fluid Sterilization Device in the Embodiment In the above embodiment, the chamber inlet 12 and the chamber outlet 13 open opposite the light source unit 20 on the side of the sterilization chamber 60 opposite the light source unit 20, and the opening area of ​​the chamber inlet 12 is smaller than the opening area of ​​the chamber outlet 13.

[0079] This makes it possible to increase the flow velocity and dynamic pressure of the fluid that flows into the sterilization chamber 60 from the chamber inlet 12, compared to when the opening area of ​​the chamber inlet 12 is equal to or larger than the opening area of ​​the chamber outlet 13. This makes it easier for the fluid that flows into the sterilization chamber 60 from the chamber inlet 12 to reach the vicinity of the light source unit 20, thereby lengthening the time the fluid stays in the sterilization chamber 60 and ultimately improving the sterilization efficiency of the fluid.

[0080] In the above embodiment, the opening area of ​​each of the plurality of chamber inlets 12 is smaller than the opening area of ​​the chamber outlet 13. This allows the flow velocity and dynamic pressure of the fluid to be increased at all of the plurality of chamber inlets 12.

[0081] In the above embodiment, the difference in opening area between the multiple chamber inlets 12 is 10% or less. This allows the fluid to flow into the sterilization chamber 60 from the multiple chamber inlets 12 as evenly as possible, making it easier for the fluid that has flowed into the sterilization chamber from the multiple chamber inlets 12 to reach close to the light source unit 20.

[0082] In the above embodiment, the auxiliary inlet 15 opens in a direction different from that of the room inlet 12, at a location in the sterilization unit 10 closer to the light source unit 20 than the room inlet 12. This makes it possible to generate a fluid flow in a direction different from that of the fluid flowing in from the room inlet 12 near the light source unit 20, thereby preventing fluid from accumulating in areas that are blind spots for ultraviolet light near the light source unit 20. This allows the fluid to be effectively irradiated with ultraviolet light, further improving sterilization efficiency.

[0083] In the above embodiment, the total opening area of ​​the chamber inlet 12 and the auxiliary inlet 15 is larger than the opening area of ​​the chamber outlet 13. This prevents an increase in pressure loss of the fluid in the sterilization chamber, even if turbulence occurs in the sterilization chamber due to fluid flowing in not only through the chamber inlet 12 but also through the auxiliary inlet 15.

[0084] In the above embodiment, the total opening area of ​​the multiple auxiliary inlets 15 is smaller than the total opening area of ​​the multiple chamber inlets 12. Specifically, the total opening area of ​​the multiple auxiliary inlets 15 is 50% or less of the total opening area of ​​the multiple chamber inlets 12. This makes it possible to prevent the flow rate of the fluid flowing in from the auxiliary inlets 15 from becoming excessive and the flow rate of the fluid flowing in from the chamber inlets from becoming insufficient.

[0085] In the above embodiment, the opening area of ​​each auxiliary inlet 15 is smaller than the opening area of ​​each chamber inlet 12. Specifically, the opening area of ​​each auxiliary inlet 15 is 25% or less of the opening area of ​​each chamber inlet 12. This effectively prevents the flow rate of the fluid flowing in from the auxiliary inlet 15 from becoming excessive and the flow rate of the fluid flowing in from the chamber inlet 12 from becoming insufficient.

[0086] In the above embodiment, the difference between the opening areas of the housing supply port 321, the chamber inlet 12, and the chamber outlet 13 is 10% or less. This prevents an increase in pressure loss of the fluid in the sterilization unit 10, even if the opening area of ​​the chamber inlet 12 is made smaller than the opening area of ​​the chamber outlet 13 to make it easier for the fluid that has flowed into the sterilization chamber 60 from the chamber inlet 12 to reach close to the light source unit 20.

[0087] In the above embodiment, the sterilization unit 10 is formed in a cylindrical shape with a bottom, the light source unit 20 is positioned so as to irradiate ultraviolet light from the opening side of the sterilization unit 10 towards the inside of the sterilization unit 10, the chamber inlet 12 and chamber outlet 13 are formed on the bottom surface of the sterilization unit 10, and the auxiliary inlet 15 is formed in a part of the cylindrical surface of the sterilization unit 10 closer to the light source unit 20. Accordingly, by appropriately positioning the chamber inlet 12 and auxiliary inlet 15, the above-mentioned effects can be effectively achieved.

[0088] When SUS is used as the material for the sterilization unit 10, as in the above embodiment, the above-mentioned effects of the chamber inlet 12 and auxiliary inlet 15 can be significantly exhibited. That is, because the reflectance of ultraviolet light on the inner surface of the sterilization chamber 60 is relatively low, the illuminance of ultraviolet light in areas of the sterilization chamber 60 far from the light source unit 20 becomes low, but the chamber inlet 12 and auxiliary inlet 15 make it easier for the fluid to reach areas close to the light source unit 20 (i.e., areas where the illuminance of ultraviolet light is high), thereby ensuring high sterilization performance.

[0089] (Modifications of the embodiment) In the above embodiment, the housing supply port 321 is formed on the side of the housing 30 opposite the chamber inlet 12, and the housing outlet 311 is formed near the chamber outlet 13, but conversely, the housing supply port 321 may be formed near the chamber inlet 12, and the housing outlet 311 may be formed on the side of the housing 30 opposite the chamber outlet 13. In this case, as in the above embodiment, the flow rate and dynamic pressure of the fluid flowing into the sterilization chamber 60 from the chamber inlet 12 can be increased, making it easier for the fluid flowing into the sterilization chamber 60 from the chamber inlet 12 to reach the vicinity of the light source unit 20, thereby improving the sterilization efficiency of the fluid.

[0090] In the above embodiment, both the chamber inlet 12 and the chamber outlet 13 are disposed at positions offset from the center of the second main body component 102 of the sterilization section 10, but the positions of the chamber inlet 12 and the chamber outlet 13 are not limited to this. For example, the chamber outlet 13 may be disposed at the center of the second main body component 102, and multiple chamber inlets 12 may be arranged circumferentially around the chamber outlet 13. In this case, the same effects as those of the above embodiment can be achieved. [Explanation of symbols]

[0091] 1 Fluid sterilizer 10 Sterilization section 12 chamber inlet 13 Chamber outlet 15 Auxiliary inlet 20 Light source section 60 Sterilization room

Claims

1. A fluid sterilization device that sterilizes a fluid by irradiating the fluid with ultraviolet light, a sterilization unit that forms a sterilization chamber through which the fluid to be sterilized by the ultraviolet light flows, has a chamber inlet for allowing the fluid to flow into the sterilization chamber and a chamber outlet for allowing the fluid to flow out of the sterilization chamber, and is made of a material that is transparent to the ultraviolet light; a light source unit that irradiates the fluid in the sterilization chamber with the ultraviolet light from one end side of the sterilization chamber, the chamber inlet and the chamber outlet open at the other end of the sterilization chamber so as to face the light source unit, A fluid sterilizing device, wherein the chamber inlet has an opening area smaller than the opening area of ​​the chamber outlet.

2. The chamber inlet has a plurality of openings in the sterilization chamber, 2. The fluid sterilizing device of claim 1, wherein the chamber inlets each have an opening area smaller than the opening area of ​​the chamber outlet.

3. 3. The fluid sterilizing device according to claim 2, wherein the difference between the opening areas of the plurality of chamber inlets is 10% or less.

4. 2. The fluid sterilization device according to claim 1, wherein an auxiliary inlet for allowing the fluid to flow into the sterilization chamber opens in a direction different from that of the chamber inlet at a portion of the sterilization unit closer to the light source unit than the chamber inlet.

5. 5. The fluid sterilizing device according to claim 4, wherein the sum of the opening areas of the chamber inlet and the auxiliary inlet is greater than the opening area of ​​the chamber outlet.

6. The chamber inlet has a plurality of openings in the sterilization chamber, The auxiliary inlet has a plurality of openings in the sterilization chamber, 5. The fluid sterilizing device according to claim 4, wherein the total opening area of ​​the plurality of auxiliary inlets is smaller than the total opening area of ​​the plurality of chamber inlets.

7. 7. The fluid sterilizing device of claim 6, wherein the total opening area of ​​the plurality of auxiliary inlets is 50% or less of the total opening area of ​​the plurality of chamber inlets.

8. 7. A fluid sterilizing device according to claim 6, wherein the respective opening areas of the auxiliary inlets are smaller than the respective opening areas of the chamber inlets.

9. 9. A fluid sterilizing device according to claim 8, wherein the individual opening areas of the auxiliary inlets are no more than 25% of the individual opening areas of the chamber inlets.

10. a housing that accommodates the sterilization unit and the light source unit and has a housing supply port through which the fluid is supplied; the housing is configured to allow the fluid to flow from the housing inlet to the chamber inlet; 10. The fluid sterilizing device according to claim 1, wherein the difference between the opening areas of the housing supply port, the chamber inlet, and the chamber outlet is 10% or less.

11. The sterilization unit is formed in a cylindrical shape with a bottom, The light source unit is arranged to irradiate the ultraviolet light from the opening side of the sterilization unit toward the inside of the sterilization unit, The chamber inlet and the chamber outlet are formed on a bottom surface of the sterilization unit, The fluid sterilizer according to claim 4 , wherein the auxiliary inlet is formed in a portion of the cylindrical surface of the sterilizer unit that is closer to the light source unit.

12. 10. The fluid sterilization device according to claim 1, wherein an inner surface of the sterilization unit that forms the sterilization chamber is made of a material that has a reflectance of 50% or less with respect to the ultraviolet light.

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