Fluid sterilizer

Abstract

To provide a fluid sterilizer that can take out sterilized fluid as desired.SOLUTION: A fluid sterilizer 1 comprises: a sterilization chamber body 10 which has a sterilization chamber 60 of fluid whose wall surface is formed in a recessed spherical surface shape, and on which an opening 14 for a light source, a chamber flow inlet 12 and a chamber flow outlet 13 are formed; and a light source part 20 which blocks the opening 14 for light source, where the chamber flow inlet 12 and the chamber flow outlet 13 are arranged such that the opening of the chamber flow inlet 12 opposes a face on the sterilization chamber 60 side out of a plane surface P including the opening 14 for a light source, and in the case where integrated radiation of ultraviolet light to fluid in the sterilization chamber 60 is divided into 7, fluid corresponding to the maximum integrated radiation out of the 7 divisions is defined as the maximum sterilization fluid, and the maximum sterilization fluid is constituted to be present only in a region where a distance Rout from an outflow center point Oout of the chamber flow outlet 13 in the sterilization chamber 60 becomes one fourth or less the diameter D of the sterilization chamber 60.SELECTED DRAWING: Figure 13

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a fluid sterilization device that uses a light-emitting element that emits ultraviolet light. This fluid sterilization device has a sterilization chamber (storage section) with a substantially concave spherical surface for containing a fluid, a chamber inlet (supply port) for introducing the fluid into the sterilization chamber, a chamber outlet (extraction port) for removing the fluid from the sterilization chamber, and a light source section for irradiating ultraviolet light.

[0003] The sterilization chamber includes a first sterilization chamber of approximately semi-concave spherical shape located upstream in the direction of fluid flow at the chamber inlet, and a second sterilization chamber of approximately semi-concave spherical shape located downstream. The chamber inlet is formed on the side of the first sterilization chamber, and the chamber outlet is formed on the side of the second sterilization chamber. The light source unit is located on the side of the second sterilization chamber. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-6710 Summary of the Invention [Problem to be solved by the invention]

[0005] In conventional fluid sterilization devices, the fluid flowing into the sterilization chamber from the chamber inlet forms a spiral flow. The central axis of this spiral flow is constant from the chamber inlet opening to the chamber outlet opening. In such a configuration, there is a risk that the fluid flowing in from the chamber inlet may reach the chamber outlet without being sufficiently irradiated with ultraviolet light. As a result, there is a possibility that some fluid may flow out of the sterilization chamber without being sufficiently sterilized.

[0006] The present invention has been made in view of such a background, and aims to provide a fluid sterilization device capable of taking out a fluid sterilized as desired.

Means for Solving the Problems

[0007] One aspect of the present invention has a sterilization chamber for a fluid in which the wall surface is formed in a concave spherical shape, and a sterilization chamber main body formed such that a light source opening, a chamber inlet for flowing the fluid into the sterilization chamber, and a chamber outlet for flowing the fluid out of the sterilization chamber open to the sterilization chamber, a light source unit configured to close the light source opening and emit ultraviolet light from the light source opening into the sterilization chamber, and the chamber inlet is arranged such that the opening of the chamber inlet faces the surface on the sterilization chamber side among the planes including the light source opening, the chamber outlet is arranged such that the opening of the chamber outlet faces the surface on the sterilization chamber side among the planes including the light source opening, When the integrated exposure dose of the ultraviolet light with respect to the fluid in the sterilization chamber is divided into seven parts, the fluid corresponding to the maximum integrated exposure dose among the seven parts is defined as the maximum sterilized fluid, In the fluid sterilization device, the maximum sterilized fluid is configured to exist only in a region where the distance from the outflow center point of the chamber outlet in the sterilization chamber is ¼ or less of the diameter of the sterilization chamber.

Effects of the Invention

[0008] According to the above aspect, the opening of the chamber inlet faces the surface on the sterilization chamber side among the planes including the light source opening, and the opening of the chamber outlet faces the surface on the sterilization chamber side among the planes including the light source opening. Therefore, the straight line connecting the opening of the chamber inlet and the opening of the chamber outlet does not pass through the center point of the sterilization chamber. Therefore, it is possible to suppress the fluid flowing into the sterilization chamber from the chamber inlet from directly heading toward the chamber outlet. Therefore, the fluid flowing in from the chamber inlet will flow through the sterilization chamber as a spiral flow.

[0009] And the maximum sterilizing fluid is configured to exist only in a region where the distance from the outflow center point of the chamber outlet in the sterilizing chamber is ¼ or less of the diameter of the sterilizing chamber. This means that the maximum sterilizing fluid among the seven divisions exists only in the vicinity of the chamber outlet. In other words, it means that there is almost no fluid with a small integrated exposure dose near the chamber outlet. Therefore, the fluid flowing out from the chamber outlet becomes the fluid sterilized as desired.

[0010] From the above, it is possible to provide a fluid sterilizing device capable of taking out the fluid sterilized as desired.

Brief Description of the Drawings

[0011]

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Embodiments for Carrying Out the Invention

[0012] The fluid sterilization device includes a sterilization chamber for the fluid whose wall surface is formed in a concave spherical shape, and a sterilization chamber main body formed such that a light source opening, a chamber inlet for flowing the fluid into the sterilization chamber, and a chamber outlet for flowing the fluid out of the sterilization chamber open to the sterilization chamber, and a light source unit configured to close the light source opening and emit ultraviolet light from the light source opening into the sterilization chamber. The chamber inlet is arranged such that the opening of the chamber inlet faces the surface on the sterilization chamber side among the planes including the light source opening. The chamber outlet is arranged such that the opening of the chamber outlet faces the surface on the sterilization chamber side among the planes including the light source opening.

[0013] When the integrated exposure dose of the ultraviolet light to the fluid in the sterilization chamber is divided into seven parts, the fluid corresponding to the maximum integrated exposure dose among the seven parts is defined as the maximum sterilized fluid. And the maximum sterilized fluid is configured to exist only in a region where the distance from the outflow center point of the chamber outlet in the sterilization chamber is ¼ or less of the diameter of the sterilization chamber.

[0014] Also, in the region where the distance from the outflow center point of the chamber outlet in the sterilization chamber is ¼ or less of the diameter of the sterilization chamber, the ratio occupied by the maximum sterilized fluid is preferably 80% or more. With this configuration, the fluid flowing out from the chamber outlet can more surely become the fluid sterilized as desired.

[0015] Also, the fluid in the sterilization chamber may be configured to form a spiral flow, and the central axis direction of the spiral flow may be configured to change from the chamber inlet to the chamber outlet. With this configuration, in the sterilization chamber, stagnant portions of the fluid can be eliminated and the flow can be improved.

[0016] Also, the central axis direction of the spiral flow may be configured to change so as to approach the central axis direction of the chamber outlet. With this configuration, the flow of the fluid near the chamber outlet can be improved.

[0017] Also, the edge line of the light source opening may be formed in a circular shape, and the ratio D / d of the diameter D of the sterilization chamber to the diameter d of the light source opening may be set in the range of 1.8 to 2.2. With this configuration, the fluid flowing in from the chamber inlet surely hits the concave spherical wall surface, and a spiral flow can be effectively generated.

[0018] Also, when viewed from the central axis direction of the light source opening, at least a part of the opening of the chamber inlet may be arranged so as not to overlap with the light source opening, and at least a part of the opening of the chamber outlet may be arranged so as not to overlap with the light source opening. With this configuration, a spiral flow can be effectively generated in the vicinity of the chamber inlet, and the generated spiral flow can be maintained until it reaches the vicinity of the chamber outlet. Furthermore, the maximum sterilizing fluid can be made to exist only in a region where the distance from the outflow center point of the chamber outlet in the sterilization chamber is ¼ or less of the diameter of the sterilization chamber.

[0019] The light source unit includes a light emitting element that emits the ultraviolet light, and the light emitting element may be configured to have two maximum illuminance axes that are symmetric with respect to the optical axis in a cross section passing through the optical axis located in the central direction within the spread of the light distribution characteristics. With this configuration, the maximum sterilizing fluid can be made to exist only in a region where the distance from the outflow center point of the chamber outlet in the sterilization chamber is ¼ or less of the diameter of the sterilization chamber.

[0020] The opening of the chamber inlet may be formed smaller than the chamber outlet. By making the opening of the chamber inlet smaller, the flow velocity of the fluid flowing into the sterilization chamber can be increased, and a spiral flow can be effectively generated. Furthermore, by making the opening of the chamber outlet larger, the fluid flowing out can be made to flow out while maintaining the spiral flow.

[0021] (Embodiment 1) 1. Basic Configuration of Fluid Sterilizer 1 The basic configuration of the fluid sterilizer 1 will be described with reference to FIG. 1. As shown in FIG. 1, the fluid sterilizer 1 mainly includes a sterilization chamber main body 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 chamber main body 10 and the light source unit 20.

[0022] A space is formed between the sterilization chamber main body 10 and the housing 30. Since this space is located outside the sterilization chamber main body 10, this space will be referred to as the outer region 70. Furthermore, the fluid sterilizer 1 includes a first seal member 40 and a second seal member 50. However, the first seal member 40 and the second seal member 50 will be described later.

[0023] The fluid sterilizer 1 is a device that allows fluid to flow from the outside into the sterilization chamber 60 via the outer region 70 and irradiates the fluid in the sterilization chamber 60 with ultraviolet light from the light source unit 20 to sterilize the fluid. 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 powdered solid, etc., as long as it has fluidity. In the case of a liquid, for example, water, oil, alcohol, a solution using these as solvents, etc.

[0024] The sterilization chamber main body 10 has the sterilization chamber 60 inside. The sterilization chamber 60 is a space that irradiates the flowing fluid with ultraviolet light emitted from the light source unit 20. The wall surface of the sterilization chamber 60 is formed in a concave spherical shape. By making the sterilization chamber 60 in a concave spherical shape, the ultraviolet light can be efficiently reflected by the concave spherical surface, and the illuminance of the ultraviolet light in the sterilization chamber 60 can be increased, so the sterilization efficiency of the fluid can be improved.

[0025] The main body 10 of the sterilization chamber is made of a material with a high reflectivity of ultraviolet light. For example, the entire main body 10 of the sterilization chamber is formed of PTFE (polytetrafluoroethylene). By using PTFE, the reflectivity of ultraviolet light can be increased, and the sterilization efficiency can be improved. As long as the material has a high reflectivity to the ultraviolet light from the light source unit 20, a material other than PTFE may be used. In particular, the material of the main body 10 of the sterilization chamber is preferably a material having a reflectivity of 80% or more, preferably 90% or more, and more preferably 95% or more with respect to the ultraviolet light from the light source unit 20. Further, only the surface layer constituting the concave spherical surface of the main body 10 of the sterilization chamber may be formed of a material having a reflectivity of 80% or more with respect to ultraviolet light, such as PTFE or aluminum.

[0026] A light source opening 14 is formed in the main body 10 of the sterilization chamber so as to open into the sterilization chamber 60. The light source opening 14 is an opening for allowing the ultraviolet light emitted from the light source unit 20 to enter the sterilization chamber 60.

[0027] A chamber inlet 12 is further formed in the main body 10 of the sterilization chamber so as to open into the sterilization chamber 60. The chamber inlet 12 connects the sterilization chamber 60 and the outer region 70. The chamber inlet 12 is an inlet for allowing fluid to flow from the outer region 70 into the sterilization chamber 60.

[0028] A chamber outlet 13 is further formed in the main body 10 of the sterilization chamber so as to open into the sterilization chamber 60. The chamber outlet 13 connects the sterilization chamber 60 and the outside. The chamber outlet 13 is an outlet for allowing fluid to flow out of the sterilization chamber 60 to the outside.

[0029] 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 that is exposed at the light source opening 14, that is, the emission surface 20A of the light source unit 20 from which the ultraviolet light is emitted, forms a 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 20A of the light source unit 20. Accordingly, the light source unit 20 is cooled by the fluid in the sterilization chamber 60. As a result, the luminous efficiency of the light source unit 20 can be increased.

[0030] The housing 30 is provided so as to enclose the sterilization chamber main body 10 and the light source unit 20. That is, the housing 30 is arranged to cover the sterilization chamber main body 10 and the light source unit 20. Specifically, the inner surface of the housing 30 faces the outer surface of the sterilization chamber main body 10. Also, the inner surface of the housing 30 faces the outer surface of the light source unit 20. That is, the inner surface of the housing 30 faces the outer back surface 20B and the outer peripheral surface 20C that constitute the outer surface of the light source unit 20.

[0031] Then, an outer region 70 is formed by the gap between the inner surface of the housing 30 and the outer surface of the sterilization chamber main body 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 region 70 is a region that faces the inner surface of the housing 30 and also faces the outer surface of the sterilization chamber main body 10. Another part of the outer region 70 is a region that faces the inner surface of the housing 30 and also faces the outer surface of the light source unit 20.

[0032] A housing supply port 31A through which fluid is supplied is formed in the housing 30. The housing supply port 31A communicates with the outer region 70. That is, the fluid supplied from the housing supply port 31A passes through the outer region 70 and flows into the sterilization chamber 60 from the chamber inlet 12.

[0033] Furthermore, a housing discharge port 32A for discharging fluid is formed in the housing 30. The housing discharge port 32A communicates with the chamber outlet 13 of the sterilization chamber main body 10. Therefore, the fluid sterilized in the sterilization chamber 60 is discharged to the outside from the housing discharge port 32A through the chamber outlet 13.

[0034] 2. Flow path of the fluid in the fluid sterilization device 1 The flow path of the fluid in the fluid sterilization device 1 will be described with reference to Fig. 2. As shown in Fig. 2, the fluid is supplied from the housing supply port 31A to the outer region 70.

[0035] First, the fluid supplied from the housing supply port 31A flows into the gap between the inner surface of the housing 30 and the outer back surface 20B of the light source unit 20 in the outer region 70. At this time, the fluid contacts the outer back surface 20B of the light source unit 20 and cools the light source unit 20. Subsequently, the fluid flows into the gap between the inner surface of the housing 30 and the outer peripheral surface 20C of the light source unit 20 in the outer region 70. At this time, the fluid contacts the outer peripheral surface 20C of the light source unit 20 and cools the light source unit 20. Subsequently, the fluid flows into the gap between the inner surface of the housing 30 and the outer surface of the sterilization chamber main body 10 in the outer region 70.

[0036] In this way, the fluid supplied from the housing supply port 31A first contacts the outer back surface 20B and the outer peripheral surface 20C, 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 31A. As a result, the luminous efficiency of the light source unit 20 can be increased.

[0037] Subsequently, the fluid in the outer region 70 flows into the sterilization chamber 60 from the chamber inlet 12 of the sterilization chamber main body 10. The fluid that has flowed into the sterilization chamber 60 proceeds toward the chamber outlet 13 while maintaining a spiral flow. The fluid flows from the chamber outlet 13 to the housing discharge port 32A and is discharged to the outside.

[0038] Here, since the sterilization chamber 60 has a concave spherical wall surface, the fluid in the sterilization chamber 60 forms a spiral flow. Further, the chamber inlet 12 and the chamber outlet 13 are configured such that the direction of the central axis of the spiral flow changes as the spiral flow generated along the concave spherical wall surface in the sterilization chamber 60 by the fluid flowing in from the chamber inlet 12 proceeds from near the chamber inlet 12 to the chamber outlet 13.

[0039] As shown in FIG. 2, the central axis direction of the spiral flow in the sterilization chamber 60 is configured to change from the chamber inlet 12 toward the chamber outlet 13. Due to the positional relationship between the chamber inlet 12 and the chamber outlet 13, the central axis direction of the spiral flow of the fluid flowing into the sterilization chamber 60 is configured to change so as to approach the direction of the central axis L3 of the chamber outlet 13.

[0040] In this embodiment, since the central axis direction of the spiral flow generated immediately after flowing in from the chamber inlet 12 has an angle with respect to the direction of the central axis L3 of the chamber outlet 13, the central axis direction of the spiral flow changes. In particular, since the angle formed by the central axis direction of the spiral flow and the direction of the central axis L3 of the chamber outlet 13 is a large angle (an angle close to 90°), the angle by which the central axis direction of the spiral flow changes becomes large. By being configured in this way, in the sterilization chamber 60, the stagnant portion of the fluid can be eliminated and the flow can be made good. In particular, the flow of the fluid in the vicinity of the chamber outlet 13 can be made good.

[0041] In this way, in the sterilization chamber 60, it is possible to suppress the fluid flowing in from the chamber inlet 12 from immediately heading toward the chamber outlet 13, and it is possible to effectively generate a spiral flow. Since the spiral flow can be maintained throughout the sterilization chamber 60, the flow path of the fluid in the sterilization chamber 60 can be lengthened. As a result, a desired integrated exposure dose by the ultraviolet light from the light source unit 20 can be ensured, and a desired sterilization performance can be ensured. Furthermore, the pressure loss can be reduced, and the sterilization efficiency can be increased.

[0042] Also, since the spiral flow can be maintained in the sterilization chamber 60, the pressure loss of the fluid in the sterilization chamber 60 can be reduced. From this also, the sterilization efficiency can be increased.

[0043] 3. Components of the Sterilization Chamber Body 10 The components of the sterilization chamber body 10 will be described with reference to FIG. 3. The sterilization chamber body 10 includes a plurality of main body components divided into at least two. A case where the sterilization chamber body 10 is composed of two main body components will be taken as an example.

[0044] As shown in Fig. 3, the sterilization chamber main body 10 is divided into two parts: a first main body component 10A and a second main body component 10B.

[0045] The first main body component 10A and the second main body component 10B are configured such that the sterilization chamber 60 is divided into two hemispherical shapes. That is, the first main body component 10A constitutes one of the plurality of main body components that make up the sterilization chamber main body 10, and its wall surface is formed in a semi-concave spherical shape. The second main body component 10B constitutes one of the plurality of main body components that make up the sterilization chamber main body 10, and its wall surface is formed in a semi-concave spherical shape. The second main body component 10B is arranged opposite to the first main body component 10A.

[0046] In the first main body component 10A and the second main body component 10B, ring-shaped boundary surfaces 10Aa and 10Ba appear as dividing surfaces, respectively. By combining the ring-shaped boundary surface 10Aa of the first main body component 10A and the ring-shaped boundary surface 10Ba of the second main body component 10B, the sterilization chamber 60 appears inside.

[0047] The diameter of the concave spherical surface of the sterilization chamber main body 10 is D. The diameter of the opening of the sterilization chamber 60 at the dividing surface between the first main body component 10A and the second main body component 10B coincides with D. By dividing the sterilization chamber main body 10 in this way, the production of the sterilization chamber main body 10 can be facilitated.

[0048] A light source opening 14 is formed in the first main body component 10A. The plane P including the light source opening 14 is configured to be a plane parallel to the boundary surfaces 10Aa and 10Ba. That is, the central axis L1 of the light source opening 14 is perpendicular to the boundary surfaces 10Aa and 10Ba. Therefore, the light source opening 14 is formed at the position farthest from the boundary surfaces 10Aa and 10Ba in the first main body component 10A. The edge line of the light source opening 14 is, for example, a circle. Therefore, the light source opening 14 is located in the same plane. The diameter of the edge line of the light source opening 14 is d.

[0049] The ratio D / d of the diameter D of the sterilization chamber 60 to the diameter d of the light source opening 14 is set, for example, in the range of 1.8 to 2.2. In this case, when centered on the center point O1 of the sterilization chamber 60, the opening angle θ1 of the light source opening 14 formed in the first main body component 10A is approximately 60°. As a similar standard, the sum of the angles θ2 and θ3 of the portion forming the concave spherical shape of the first main body component 10A is the remaining 120° (60° each). With this configuration, the fluid flowing in from the chamber inlet 12 surely hits the concave spherical wall surface, and a spiral flow can be effectively generated. As a result, the pressure loss can be reduced, and the sterilization efficiency can be increased.

[0050] The second main body component 10B is formed with a chamber inlet 12 and a chamber outlet 13. The central axis L2 of the chamber inlet 12 is offset from the center point O1 of the sterilization chamber 60. The central axis L2 of the chamber inlet 12 is formed parallel to the central axis L1 of the light source opening 14. However, if the central axis L2 of the chamber inlet 12 is offset from the center point O1, the central axis L2 of the chamber inlet 12 and the central axis L1 of the light source opening 14 may have an intersecting positional relationship or a twisted positional relationship.

[0051] The chamber inlet 12 has, for example, a cylindrical inner peripheral surface. The inner diameter of the chamber inlet 12 is di. Since the central axis L2 of the chamber inlet 12 is offset from the center point O1 of the sterilization chamber 60, the edge line of the opening on the sterilization chamber 60 side in the chamber inlet 12 has a shape approximated to an oval.

[0052] The chamber inlet 12 is arranged such that the opening on the sterilization chamber 60 side in the chamber inlet 12 faces the surface on the sterilization chamber 60 side of the plane P including the light source opening 14. In Fig. 3(b), the opening on the sterilization chamber 60 side in the chamber inlet 12 faces downward, and the surface on the sterilization chamber 60 side of the plane P including the light source opening 14 faces upward.

[0053] The central axis L3 of the chamber outlet 13 is offset from the center point O1 of the sterilization chamber 60. The central axis L3 of the chamber outlet 13 is formed parallel to the central axis L2 of the chamber inlet 12. Therefore, the central axis L3 of the chamber outlet 13 is also formed parallel to the central axis L1 of the light source opening 14. However, if the central axis L3 of the chamber outlet 13 is offset from the center point O1, the central axis L3 of the chamber outlet 13 and the central axis L2 of the chamber inlet 12 may have an intersecting positional relationship or a torsional positional relationship. Also, the central axis L3 of the chamber outlet 13 and the central axis L1 of the light source opening 14 may have an intersecting positional relationship or a torsional positional relationship.

[0054] The chamber outlet 13 has, for example, a cylindrical inner peripheral surface. The inner diameter of the chamber outlet 13 is do. Since the central axis L3 of the chamber outlet 13 is offset from the center point O1 of the sterilization chamber 60, the edge line of the opening on the sterilization chamber 60 side in the chamber outlet 13 has a shape approximated to an oval.

[0055] The chamber outlet 13 is arranged such that the opening on the sterilization chamber 60 side in the chamber outlet 13 faces the surface on the sterilization chamber 60 side of the plane P including the light source opening 14. In FIG. 3(b), the opening on the sterilization chamber 60 side in the chamber outlet 13 faces downward, and the surface on the sterilization chamber 60 side of the plane P including the light source opening 14 faces upward.

[0056] As described above, the central axis L1 of the light source opening 14 is orthogonal to the boundary surfaces 10Aa, 10Ba. In this case, the entire surfaces of the boundary surfaces 10Aa, 10Ba become the surfaces having the maximum angle with respect to the central axis L1 of the light source opening 14. Therefore, the amount of ultraviolet light entering the boundary surfaces 10Aa, 10Ba can be reduced, and thus the leakage of ultraviolet light through the boundary surfaces 10Aa, 10Ba can be reduced.

[0057] 4. Positional Relationship of Each Opening 12, 13, 14 of the Sterilization Chamber Body 10 The positional relationship of each opening 12, 13, 14 of the sterilization chamber body 10 will be described with reference to FIG. 4. Specifically, the positional relationship of the chamber inlet 12, the chamber outlet 13, and the light source opening 14 will be described.

[0058] As described above, the central axis L1 of the light source opening 14, the central axis L2 of the chamber inlet 12, and the central axis L3 of the chamber outlet 13 are, for example, parallel. And the edge line of the light source opening 14, the cross-sectional shape of the inner peripheral surface of the chamber inlet 12, and the cross-sectional shape of the inner peripheral surface of the chamber outlet 13 are each circular.

[0059] The chamber inlet 12 is arranged such that the opening of the chamber inlet 12 faces the surface on the sterilization chamber 60 side in the plane P including the light source opening 14. When viewed from the direction of the central axis L1 of the light source opening 14, at least a part of the opening of the chamber inlet 12 is arranged so as not to overlap the light source opening 14. In the present embodiment, when viewed from the direction of the central axis L1 of the light source opening 14, another part of the opening of the chamber inlet 12 is arranged so as to overlap the light source opening 14. That is, the chamber inlet 12 is positioned such that only at least a part of it is outside the light source opening 14 when viewed from the direction shown in FIG. 4.

[0060] As described above, when viewed from the direction of the central axis L1 of the light source opening 14, at least a part of the opening of the chamber inlet 12 is arranged so as not to overlap the light source opening 14. The central axis L1 of the light source opening 14 and the central axis L2 of the chamber inlet 12 are parallel. That is, when viewed from the direction of the central axis L2 of the chamber inlet 12, at least a part of the opening of the chamber inlet 12 is also arranged so as not to overlap the light source opening 14.

[0061] Therefore, all of the fluid flowing in from the chamber inlet 12 does not all proceed toward the light source opening, and at least a part of the flowing-in fluid hits the concave spherical wall surface of the sterilization chamber 60. In this way, by at least a part of the flowing-in fluid hitting the concave spherical wall surface, a spiral flow can be generated in the sterilization chamber. And by generating a spiral flow immediately after flowing into the sterilization chamber 60, the spiral flow can be maintained in all regions of the concave spherical sterilization chamber 60. Therefore, a desired integrated exposure dose can be ensured, and a desired sterilization performance can be ensured.

[0062] In addition to the above configuration, when viewed from the direction of the central axis L1 of the light source opening 14, all of the openings of the chamber inlet 12 may be arranged so as not to overlap the light source opening 14. That is, when viewed from the direction of the central axis L2 of the chamber inlet 12, all of the openings of the chamber inlet 12 may be arranged so as not to overlap the light source opening 14. In this case, a spiral flow can be effectively generated in the sterilization chamber 60. By generating a stronger spiral flow immediately after flowing into the sterilization chamber 60, the spiral flow can be maintained in all regions of the concave spherical sterilization chamber 60.

[0063] The chamber outlet 13 is arranged such that the opening of the chamber outlet 13 faces the surface on the sterilization chamber 60 side of the plane P including the light source opening 14. When viewed from the direction of the central axis L1 of the light source opening 14, at least a part of the opening of the chamber outlet 13 is arranged so as not to overlap the light source opening 14. In the present embodiment, when viewed from the direction of the central axis L1 of the light source opening 14, another part of the opening of the chamber outlet 13 is arranged so as to overlap the light source opening 14. That is, also in the chamber outlet 13, when viewed from the direction shown in FIG. 4, its position is set such that only at least a part of it is outside the light source opening 14.

[0064] As described above, when viewed from the direction of the central axis L1 of the light source opening 14, at least a part of the opening of the chamber outlet 13 is arranged so as not to overlap the light source opening 14. The central axis L1 of the light source opening 14 and the central axis L3 of the chamber outlet 13 are parallel. That is, when viewed from the direction of the central axis L3 of the chamber outlet 13, at least a part of the opening of the chamber outlet 13 is also arranged so as not to overlap the light source opening 14.

[0065] Therefore, at least a part of the fluid flowing toward the chamber outlet 13 flows toward the chamber outlet 13 while hitting the concave spherical wall surface in the sterilization chamber 60. The fluid flowing toward the chamber outlet 13 can be in a state of maintaining a spiral flow. As a result, the fluid flowing from the chamber inlet 12 to the chamber outlet 13 can maintain a spiral flow throughout. Since a spiral flow can be maintained in the sterilization chamber 60, the pressure loss of the fluid in the sterilization chamber 60 can be reduced, and the sterilization efficiency can be increased. Therefore, a desired integrated exposure dose can be ensured, and a desired sterilization performance can be ensured.

[0066] In addition to the above configuration, when viewed from the direction of the central axis L1 of the light source opening 14, all of the openings of the chamber outlet 13 may be arranged so as not to overlap the light source opening 14. That is, when viewed from the direction of the central axis L3 of the chamber outlet 13, all of the openings of the chamber outlet 13 may be arranged so as not to overlap the light source opening 14. In this case, a strong spiral flow can be maintained in the fluid flowing toward the chamber outlet 13.

[0067] Also, the inner diameter of the chamber outlet 13 is formed larger than the inner diameter of the chamber inlet 12. By reducing the inner diameter of the chamber inlet 12, the flow velocity flowing into the sterilization chamber 60 can be increased, and a spiral flow can be effectively generated. Further, by increasing the inner diameter of the chamber outlet 13, the fluid flowing out can be made to flow out while maintaining a spiral flow. Therefore, the pressure loss in the vicinity of the chamber outlet 13 can be reduced, and the sterilization efficiency can be increased.

[0068] When viewed from the direction shown in FIG. 4, the ratio of the area outside the light source opening 14 in the area of the chamber inlet 12 and the chamber outlet 13 is preferably 50% or more, and more preferably the larger the better. This makes it easier to form a spiral flow. Note that this area ratio needs to be set according to the diameter D of the sterilization chamber 60, the inner diameter di of the chamber inlet 12, and the inner diameter do of the chamber outlet 13.

[0069] 5. Configuration of the boundary surfaces 10Aa, 10Ba and the first seal member 40 The boundary surface 10Aa of the first main body component 10A, the boundary surface 10Ba of the second main body component, and the first seal member 40 will be described with reference to FIG. 3.

[0070] The boundary surface 10Aa of the first main body component 10A is formed in a ring shape. A ring-shaped concave groove 15 is formed in the boundary surface 10Aa. This concave groove 15 is provided to fit the ring-shaped first seal member 40 and fix the position of the first seal member 40 on the boundary surface 10Aa. The cross-sectional shape of the concave groove 15 can be arbitrary as long as it can fit the first seal member 40, such as a rectangle, a V shape, or a circle.

[0071] The first seal member 40 is formed of fluororubber or fluoroelastomer. Both materials are elastic materials that are resistant to deterioration by ultraviolet light and have a high reflectivity of ultraviolet light. The first seal member 40 is exemplified by a ring shape with a circular cross-section, but can have an arbitrary cross-sectional shape.

[0072] The first seal member 40 is fitted into the concave groove 15. By fitting the first seal member 40 into the concave groove 15, the first seal member 40 on the boundary surface 10Aa of the first main body component 10A can be fixed and stabilized, and positioned. Also, by fitting the first seal member 40 into the concave groove 15, the exposed area of the first seal member 40 can be reduced so that ultraviolet light is not directly irradiated onto the first seal member 40. Therefore, the lifespan of the first seal member 40 can be improved.

[0073] As shown in Fig. 3(b), in the fluid sterilization device 1, the boundary surface 10Aa of the first main body component 10A and the boundary surface 10Ba of the second main body component 10B are arranged to face each other. And the sterilization chamber main body 10 is arranged to be pressed by the housing 30 inside the housing 30 in the vertical direction of Fig. 3(b). By this pressing, the first seal member 40 adheres to the boundary surface 10Aa of the first main body component 10A and the boundary surface 10Ba of the second main body component 10B over the entire circumference in the circumferential direction. In this way, the first seal member 40 partitions the sterilization chamber 60 and the outer region 70.

[0074] In this state, the boundary surface 10Aa of the first main body component 10A and the boundary surface 10Ba of the second main body component 10B are in a state of being in close contact or having a slight gap. In this way, the sterilization chamber 60 is constituted by the semi-concave spherical surface of the first main body component 10A and the semi-concave spherical surface of the second main body component 10B, and the sterilization chamber main body 10 is constituted.

[0075] With the above configuration, even if fluid infiltrates from the sterilization chamber 60 into the boundary surfaces 10Aa and 10Ba of the first main body component 10A and the second main body component 10B, the fluid does not flow outside this by the first seal member 40. That is, the boundary surfaces 10Aa and 10Ba of the first main body component 10A and the second main body component 10B are sealed by the first seal member 40, and leakage of fluid between the sterilization chamber 60 and the outer region 70 can be prevented.

[0076] Depending on the dimensional accuracy and surface roughness of the boundary surfaces 10Aa and 10Ba, there may be a case where they are in contact in a part in the circumferential direction and separated in the remaining parts in the circumferential direction. Even in these cases, the first seal member 40 adheres to the boundary surface 10Ba of the second main body component 10B over the entire circumference. Therefore, the same effect as above is exhibited.

[0077] In addition, since the first sealing member 40 is made of fluororubber or fluoroelastomer, even if ultraviolet light from the light source unit 20 enters the interface surfaces 10Aa and 10Ba between the first main body component 10A and the second main body component 10B, the ultraviolet light can be reflected by the first sealing member 40. Therefore, it is possible to prevent ultraviolet light from leaking to the outside of the sterilization chamber main body 10 from the interface surfaces 10Aa and 10Ba between the first main body component 10A and the second main body component 10B.

[0078] In addition, since the first sealing member 40 is fitted into the concave groove 15, the ultraviolet light from the light source opening 14 is not directly irradiated. Therefore, the service life of the first sealing member 40 can be improved.

[0079] In this embodiment, the sterilization chamber main body 10 is composed of two members, the first main body component 10A and the second main body component 10B, but it may be composed of three or more main body components. Also in that case, by arranging the first sealing member 40 at the interface with each main body component, it is possible to prevent leakage of fluid between the sterilization chamber 60 and the outer region 70, and to prevent leakage of ultraviolet light to the outside of the sterilization chamber main body 10.

[0080] In this embodiment, the concave groove 15 is provided in the first main body component 10A, but it may be provided in the second main body component 10B, or may be provided in both.

[0081] 6. Configuration of the light source unit 20 The configuration of the light source unit 20 will be described with reference to FIG. 5. FIG. 5 is a cross-sectional view showing the configuration of the light source unit 20. The light source unit 20 is arranged so as to close the light source opening 14 of the sterilization chamber main body 10. Also, the ultraviolet light emitting side of the light source unit 20 is arranged to face the sterilization chamber 60 side. The ultraviolet light emitted from the light source unit 20 enters the sterilization chamber 60 through the light source opening 14.

[0082] The light source unit 20 includes a mounting substrate 21, a light emitting element 22, a window member 23, a light source housing 24, and a gasket 25. The shape of the entire light source unit 20 is, for example, a disk shape. However, the shape of the light source unit 20 can be an arbitrary shape.

[0083] The mounting substrate 21 is a substrate having a mounting surface. A wiring pattern is formed on the mounting substrate 21. A wiring 80 for supplying power is connected to the back surface of the mounting substrate 21.

[0084] 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 the emission wavelength is 200 to 280 nm. Since the emission wavelength is in the UVC region, the fluid can be efficiently sterilized. The light emitting element 22 may be directly mounted on the mounting surface of the mounting substrate 21, or a packaged LED package may be mounted on the mounting surface of the mounting substrate 21. The LED package is a unit in which the light emitting element 22 is disposed in a housing and sealed with a glass plate or a lens. Also, various elements (for example, a Zener diode) necessary for driving and protecting the light emitting element 22 are mounted on the mounting surface of the mounting substrate 21.

[0085] The window member 23 is a circular glass plate and is disposed on the gasket 25. The window member 23 is made of quartz. Other materials than quartz may be used as long as they are materials that transmit ultraviolet light. For example, sapphire or the like may be used. Also, the window member 23 is not limited to a plate shape and may be a lens shape, for example, a TIR lens, a fly-eye lens, a Fresnel lens, or the like.

[0086] The light source housing 24 is provided so as to cover other parts so as 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 the side surface of the mounting substrate 21 and the side surface of the window member 23. The light source housing 24 may be constituted by one member or may be constituted by a plurality of members.

[0087] The light source housing 24 is formed of a material with high heat dissipation. For example, the light source housing 24 is formed of a metal such as SUS or Al, or a resin material with high heat dissipation. Since the light source housing 24 of the light source unit 20 is in contact with the fluid, the light source unit 20 can be efficiently cooled.

[0088] The gasket 25 is formed in a ring shape and is arranged on the mounting substrate 21 along the vicinity of the end portion. The light emitting element 22 and various elements are located inside the gasket 25. The height of the gasket 25 is set higher than that of the light emitting element 22 and various elements. The gasket 25 is made of an elastic material resistant to ultraviolet light. It may be made of the same material as the first sealing member 40.

[0089] The gasket 25 is elastically deformed and is in close contact with the mounting substrate 21, the window member 23, and the light source housing 24. Thereby, the internal space surrounded by the light source housing 24, the window member 23, and the gasket 25 is sealed so that the fluid does not leak into the internal space. Therefore, the fluid can be prevented from entering the region where the light emitting element 22 and various elements are arranged. Note that the gasket 25 may be in close contact with only the mounting substrate 21 and the window member 23, or may be in close contact with only the window member 23 and the light source housing 24.

[0090] Here, the outer surface of the light source unit 20 has an emission surface 20A that emits ultraviolet light, an outer back surface 20B located on the back surface of the emission surface, and an outer peripheral surface 20C. The emission surface 20A is located corresponding to the light source opening 14 and is constituted by a portion of the window member 23 that is not covered by the light source housing 24. That is, the emission surface 20A is constituted by the surface of the window member 23. The outer back surface 20B is constituted by a portion on the back surface side of the light source housing 24. The outer peripheral surface 20C is constituted by a portion of the outer peripheral surface of the light source housing 24.

[0091] 7. Configuration of the housing 30 and the second sealing member 50 The configuration of the housing 30 and the second seal member 50 will be described with reference to FIGS. 1, 6, and 7. As described above, the housing 30 is provided so as to enclose the sterilization chamber main body 10 and the light source unit 20. The housing 30 includes a first housing member 31 and a second housing member 32. The splitting position between the first housing member 31 and the second housing member 32 can be set arbitrarily. Also, the housing 30 may be constituted by one member, or may be constituted by three or more members. Note that the joint portion between the first housing member 31 and the second housing member 32 has a seal structure (not shown).

[0092] The first housing member 31 is configured to cover a part of the outer surface of the sterilization chamber main body 10 and the outer surface of the light source unit 20. Accordingly, a part of the outer region 70 is formed between the inner surface of the first housing member 31 and the outer surfaces of the sterilization chamber main body 10 and the light source unit 20.

[0093] A housing supply port 31A is formed in the first housing member 31. The housing supply port 31A is formed in a cylindrical shape, for example, a cylindrical shape or a polygonal cylindrical shape. As shown in FIGS. 1 and 6, the housing supply port 31A is arranged so as to face the outer back surface 20B of the light source unit 20. When viewed from the central axis direction of the housing supply port 31A, at least a part of the opening of the housing supply port 31A is set to face the outer back surface of the light source unit 20. Thereby, the fluid flowing into the outer region 70 from the housing supply port 31A can directly hit the light source unit 20, and the cooling efficiency of the light source unit 20 can be improved.

[0094] In particular, when viewed from the central axis direction of the housing supply port 31A, it is preferable that the entire opening of the housing supply port 31A is set to face the outer back surface 20B of the light source unit 20. The cooling efficiency of the light source unit 20 can be further improved.

[0095] Furthermore, the first housing member 31 is provided with an opening 31B for passing a wiring 80 that connects the light source unit 20 and the outside. The opening 31B is, for example, cylindrical, and one end of the cylinder is in contact with the outer back surface 20B of the light source unit 20. By passing the wiring 80 through the inside of the cylinder of the opening 31B, the connection part between the light source unit 20 and the wiring 80 and the wiring 80 are prevented from coming into contact with the fluid.

[0096] The second housing member 32 is configured to cover the remaining part of the outer surface of the sterilization chamber main body 10. A part of the outer region 70 is formed between the inner surface of the second housing member 32 and the outer surface of the sterilization chamber main body 10.

[0097] A housing discharge port 32A is formed in the second housing member 32. The housing discharge port 32A is connected to the chamber outlet 13 of the sterilization chamber main body 10. The connection structure between the chamber outlet 13 of the sterilization chamber main body 10 and the housing discharge port 32A of the housing 30 will be described with reference to FIG. 7.

[0098] As shown in FIG. 7, the housing discharge port 32A has a cylindrical portion 32Aa that protrudes toward the chamber outlet 13, and is connected to the chamber outlet 13 by fitting the cylindrical portion 32Aa into the chamber outlet 13. Further, in the chamber outlet 13, the region on the housing discharge port 32A side has a larger inner diameter than the other regions, and the inner diameter approximately matches the outer diameter of the cylindrical portion 32Aa.

[0099] Due to this difference in inner diameter, a stepped portion 13A is formed in the chamber outlet 13. A ring-shaped second seal member 50 is disposed on the stepped portion 13A. The second seal member 50 is formed of the same material as the first seal member 40. That is, the second seal member 50 is formed of fluororubber or fluoroelastomer.

[0100] The second seal member 50 is formed in a ring shape. The second seal member 50 is disposed between the boundary surfaces of the chamber outlet 13 and the housing outlet 32A. The second seal member 50 is elastically deformed by the pressing force from the housing 30, and is in close contact with both the stepped portion 13A of the chamber outlet 13 and the tip of the cylindrical portion 32Aa of the housing outlet 32A. With such a structure, the second seal member 50 seals the boundary surface between the chamber outlet 13 and the housing outlet 32A. Therefore, the second seal member 50 prevents the leakage of fluid between the chamber outlet 13 and the outer region 70 through the boundary surface between the chamber outlet 13 and the housing outlet 32A.

[0101] 8. Angle θ4 formed by the tangent line at the light source opening 14 in the sterilization chamber 60 The angle θ4 formed by the tangent line at the light source opening 14 in the sterilization chamber 60 will be described with reference to FIG. 8.

[0102] In FIG. 8, L4 and L5 are tangent lines at the light source opening 14 in the sterilization chamber 60 in the cross-section of the sterilization chamber body 10 passing through the central axis L1 of the light source opening 14. The angle formed by the tangent lines L4 and L5 is θ4.

[0103] As described above, the ratio D / d of the diameter D of the sterilization chamber 60 to the diameter d of the light source opening 14 is set in the range of 1.8 to 2.2. When the ratio D / d is 2.0, the angle θ4 formed by the tangent lines L4 and L5 is 120°. When the ratio D / d is 1.8, the formed angle θ4 is approximately 113°. When the ratio D / d is 2.2, the formed angle θ4 is approximately 126°.

[0104] When the ratio D / d is in the range of 1.8 to 2.0, the formed angle θ4 is in the range of 113° to 120°. The reason will be described later, but it is better if the ratio D / d is set in the range of 1.8 to 2.0.

[0105] 9. Light distribution characteristics of the light emitting element 22 The light distribution characteristics of the light-emitting element 22 will be described with reference to FIG. 9. As shown in FIG. 9, the light distribution characteristics of the light-emitting element 22 form a heart shape. Specifically, the light-emitting element 22 is configured to have two maximum illuminance axes that are symmetric with respect to the optical axis (the position of 0° in FIG. 9) located in the central direction within the spread of the light distribution characteristics, in a cross-section passing through the optical axis. The maximum illuminance axes are at two locations near +30° and -30°.

[0106] In the light distribution characteristics shown in FIG. 9, the axes where the illuminance is 50% of the maximum value are located near +60° and -60°. Therefore, in the light distribution characteristics shown in FIG. 9, the half-value angle, which is the angle between the axes where the illuminance is 50% of the maximum value, is 120°. Although the reason will be described later, it is preferable that the half-value angle be set in the range of 110° to 130°.

[0107] 10. Relationship between the aperture 14 for the light source and the half-value angle θ5 of the light-emitting element 22 The relationship between the aperture 14 for the light source in the sterilization chamber 60 and the half-value angle θ5 of the light-emitting element 22 will be described with reference to FIGS. 8 to 10.

[0108] The sterilization chamber main body 10 and the light source unit 20 are arranged such that the central axis L1 of the aperture 14 for the light source shown in FIG. 8 coincides with the optical axis L6 of the light-emitting element 22 shown in FIG. 10.

[0109] As shown in FIGS. 9 and 10, the half-value angle θ5 of the light-emitting element 22 is the angle formed by the axes L7 and L10 where the illuminance is 50% of the maximum value. The half-value angle θ5 is set, for example, near 120°. For example, the half-value angle θ5 is set in the range of -10° to +10° centered on 120°. That is, the half-value angle θ5 is set in the range of 110° to 130°.

[0110] As shown in FIG. 10, on the emission surface 20A of the light source unit 20, the diameter of the region included in the range of the half-value angle θ5 of the light-emitting element 22 is d1. That is, on the emission surface 20A of the light source unit 2, the distance between the intersections with the axes L7 and L10 corresponding to the half-value angle θ5 of the light-emitting element 22 is d1.

[0111] Also, on the emission surface 20A of the light source unit 20, the diameter of the region included in the range of -10° of the half-value angle θ5 of the light-emitting element 22 is d2. That is, on the emission surface 20A of the light source unit 20, the distance between the intersections of the axes L8 and L11 corresponding to -10° of the half-value angle θ5 of the light-emitting element 22 is d2. The axes L8 and L11 corresponding to -10° of the half-value angle θ5 of the light-emitting element 22 are the axis at -5° from the axis L7 and the axis at +5° from the axis L10. Here, in FIG. 10, the positive angle is the clockwise angle.

[0112] Also, on the emission surface 20A of the light source unit 20, the diameter of the region included in the range of +10° of the half-value angle θ5 of the light-emitting element 22 is d3. That is, on the emission surface 20A of the light source unit 20, the distance between the intersections of the axes L9 and L12 corresponding to +10° of the half-value angle θ5 of the light-emitting element 22 is d3. The axes L9 and L12 corresponding to +10° of the half-value angle θ5 of the light-emitting element 22 are the axis at -5° from the axis L7 and the axis at +5° from the axis L10.

[0113] And the light source aperture 14 is formed such that the edge line of the light source aperture 14 is included in the region constituting -10° to +10° of the half-value angle θ5 of the light-emitting element 22. Therefore, in FIG. 10, one of the edge lines of the light source aperture 14 is located between the axes L8 and L9, and the other of the edge lines of the light source aperture 14 is located between the axes L11 and L12. That is, the diameter d of the light source aperture 14 is included in the diameters d2 to d3 of the region included in the range of -10° to +10° of the half-value angle θ5 of the light-emitting element 22.

[0114] As described above, the edge line of the light source opening 14 is positioned so as to be included in the region that constitutes -10° to +10° of the half-value angle θ5 of the light-emitting element 22. And, -10° to +10° of the half-value angle θ5 of the light-emitting element 22 is the angle at which the illuminance is near 50% of the maximum value. Therefore, the region that constitutes -10° to +10° of the half-value angle θ5 of the light-emitting element 22 is a region having an illuminance of 50% or more of the maximum value. That is, the illuminance of the ultraviolet light emitted from the light source opening 14 has an illuminance of 50% or more of the maximum value. Inside the sterilization chamber 60, ultraviolet light having an illuminance of 50% or more of the maximum value is irradiated, and the fluid flowing through the sterilization chamber 60 can be efficiently sterilized.

[0115] In particular, the half-value angle θ5 is set to 110° to 130°. For example, when the half-value angle θ5 is 110°, it is as follows. In the spread of the light distribution characteristics of the light-emitting element 22, in the range from +55° to -55° with respect to the optical axis L6 located in the central direction as the central axis, the illuminance is 50% or more. And, the region that constitutes -10° to +10° of the half-value angle θ5 is in the range of the light distribution angle of 100° to 120° when the optical axis L6 is the central axis. In this case, it is formed so that the edge line of the light source opening 14 is included in the range of the light distribution angle of 100° to 120°.

[0116] When the half-value angle θ5 is 120°, it is formed so that the edge line of the light source opening 14 is included in the range of the light distribution angle of 110° to 130° when the optical axis L6 is the central axis. When the half-value angle θ5 is 130°, it is formed so that the edge line of the light source opening 14 is included in the range of the light distribution angle of 120° to 140° when the optical axis L6 is the central axis.

[0117] By setting the half-value angle θ5 to 110° to 130° in this way, ultraviolet light with high illuminance can be emitted into the concave spherical sterilization chamber 60. Therefore, the sterilization efficiency can be enhanced.

[0118] Further, the light-emitting element 22 is configured to have two maximum illuminance axes that are symmetric with respect to the optical axis L6 in a cross section passing through the optical axis L6 located in the central direction within the spread of the light distribution characteristics. That is, the light distribution characteristics of the light-emitting element 22 are heart-shaped. By using the light-emitting element 22 having such light distribution characteristics, ultraviolet light can be evenly irradiated into the sterilization chamber 60. As a result, the sterilization efficiency can be increased.

[0119] Furthermore, the edge line of the light source opening 14 is formed in a circular shape. Thereby, ultraviolet light having a desired illuminance can be appropriately emitted into the sterilization chamber 60. As a result, the sterilization efficiency can be increased.

[0120] Also, the ratio D / d of the diameter D of the sterilization chamber 60 to the diameter d of the light source opening 14 is set in the range of 1.8 to 2.2. By setting the ratio D / d in the range of 1.8 to 2.2, ultraviolet light having a desired illuminance can be irradiated within the concave spherical sterilization chamber 60.

[0121] In particular, when the half-value angle θ5 is 120°, when the ratio D / d is 2.0, the boundary surface of the half-value angle θ5 coincides with the tangents L4 and L5 at the light source opening 14 in the sterilization chamber 60. Therefore, when the half-value angle θ5 is 120° and the ratio D / d is 2.0, ultraviolet light can be irradiated most appropriately. Therefore, it is preferable that the half-value angle θ5 is 110° to 130° and the ratio D / d is set in the range of 1.8 to 2.2. By configuring in this way, the illuminance of the ultraviolet light emitted from the light source opening 14 can be made more than half-value, and the sterilization efficiency can be increased.

[0122] And the light-emitting element 22 is arranged such that the optical axis L6 located in the central direction within the spread of the light distribution characteristics coincides with the central axis L1 of the circle that is the edge line of the light source opening 14. Thereby, ultraviolet light having a desired illuminance can be irradiated into the sterilization chamber 60.

[0123] 11. Water Flow Simulation The sterilization chamber 60 in this embodiment was modeled and a water flow simulation was performed. As shown in Fig. 11, the water flow simulation results show that a spiral flow is formed in the sterilization chamber 60.

[0124] Also, when the flow rate of water flowing through the sterilization chamber 60 per unit time is 8 L / sec, the time from when the water flows in from the chamber inlet 12 until it flows out from the chamber outlet 13, that is, the residence time in the sterilization chamber 60, was 0.14 sec. The sterilization performance of the outflowing water was very high, and it was confirmed that the sterilization or inactivation of the target bacteria and viruses was 90% or more.

[0125] From the above, it is preferable that the sterilization chamber main body 10 be configured such that when the flow rate of the fluid flowing through the sterilization chamber 60 per unit time is 0.5 to 50 L / sec, the residence time of the fluid in the sterilization chamber 60 is 0.02 to 2 sec. Thereby, a desired integrated irradiation dose can be ensured, and a desired sterilization performance can be ensured.

[0126] 12. Integrated Irradiation Dose in Sterilization Chamber 60 The integrated irradiation dose of ultraviolet light on the fluid in the sterilization chamber 60 will be described with reference to Fig. 12. As described above (see Fig. 11), as can be seen from the water flow simulation results, a spiral flow is formed in the sterilization chamber 60.

[0127] In the water flow simulation, the relationship between the position of the sterilization chamber 60 and the integrated irradiation dose will be analyzed in more detail. The integrated irradiation dose of ultraviolet light on the fluid in the sterilization chamber 60 is divided into seven parts. As shown in Fig. 12, the regions where the fluid corresponding to each integrated irradiation dose exists are designated as A1, A2, A3, A4, A5, A6, and A7 in ascending order of the integrated irradiation dose. In actuality, since the sterilization chamber 60 is formed in a substantially concave spherical shape, it is a three-dimensional region, but in Fig. 12, it is shown schematically in cross-section.

[0128] The painted portion in Fig. 12 is the region A7 where the fluid corresponding to the maximum integrated exposure amount among the seven divisions exists. Here, for the sake of explanation, the fluid corresponding to the maximum integrated exposure amount is defined as the maximum sterilization fluid. That is, the region A7 is the region where the maximum sterilization fluid exists.

[0129] 13. Positional relationship between the region A7 where the maximum sterilization fluid exists and the chamber outlet 13 The positional relationship between the region A7 where the maximum sterilization fluid exists and the chamber outlet 13 will be described with reference to Fig. 13. In Fig. 13, the boundary line "A6 / A7" between the region A7 where the maximum sterilization fluid exists and the region A6 where the fluid corresponding to the second largest integrated exposure amount exists is shown by a dashed line.

[0130] Fig. 13 shows the outflow center point Oout of the chamber outlet 13 in the sterilization chamber 60. The outflow center point Oout is the center point at the boundary opening between the concave spherical surface constituting the sterilization chamber 60 and the chamber outlet. Further, Fig. 13 shows a partial spherical region Aout with a radius of the distance Rout from the outflow center point Oout. The distance Rout is one-fourth of the diameter D of the sterilization chamber 60. Further, Fig. 13 shows the contour Bout of the partial spherical region Aout by a two-dot chain line.

[0131] Therefore, as shown in Fig. 13, the maximum sterilization fluid is configured to exist only in the partial spherical region Aout where the distance Rout from the outflow center point Oout is one-fourth or less of the diameter D of the sterilization chamber 60. More specifically, in the partial spherical region Aout, the ratio occupied by the maximum sterilization fluid is 80% or more.

[0132] According to the above-described fluid sterilization device 1, the opening of the chamber inlet 12 faces the surface on the sterilization chamber 60 side of the plane P including the light source opening 14, and the opening of the chamber outlet 13 faces the surface on the sterilization chamber 60 side of the plane P including the light source opening 14. Therefore, the straight line connecting the opening of the chamber inlet 12 and the opening of the chamber outlet 13 does not pass through the center point O1 of the sterilization chamber 60. Therefore, it is possible to suppress the fluid flowing into the sterilization chamber 60 from the chamber inlet 12 from directly heading toward the chamber outlet 13. Therefore, the fluid flowing in from the chamber inlet 12 will flow through the sterilization chamber 60 as a spiral flow.

[0133] In particular, the central axis direction of the spiral flow is configured to change from the chamber inlet 12 toward the chamber outlet 13. With this configuration, in the sterilization chamber 60, stagnant portions of the fluid can be eliminated and the flow can be made good. That is, a smooth spiral flow is formed in the sterilization chamber 60. Furthermore, by changing the central axis direction of the spiral flow so as to approach the central axis direction of the chamber outlet 13, the flow of the fluid in the vicinity of the chamber outlet 13 can be made good.

[0134] By forming such a spiral flow, the maximum sterilization fluid is configured to exist only in a region where the distance Rout from the outflow center point Oout of the chamber outlet 13 in the sterilization chamber 60 is ¼ or less of the diameter D of the sterilization chamber 60. This means that the maximum sterilization fluid among the seven divisions exists only in the vicinity of the chamber outlet 13. In other words, it means that there is almost no fluid with a small integrated exposure dose in the vicinity of the chamber outlet 13. Therefore, the fluid flowing out from the chamber outlet 13 becomes a fluid sterilized as desired.

[0135] Furthermore, when viewed from the direction of the central axis L1 of the light source opening 14, at least a part of the opening of the chamber inlet 12 is arranged so as not to overlap the light source opening 14, and at least a part of the opening of the chamber outlet 13 is arranged so as not to overlap the light source opening 14. With this configuration, a spiral flow can be effectively generated in the vicinity of the chamber inlet 12, and the generated spiral flow can be maintained until it reaches the vicinity of the chamber outlet 13. These also contribute to the fact that the maximum sterilization fluid exists only in a region where the distance Rout from the outflow center point Oout of the chamber outlet 13 in the sterilization chamber 60 is ¼ or less of the diameter D of the sterilization chamber 60.

[0136] Also, configuring the light distribution characteristics of the light emitting element 22 as described above also contributes to the fact that the maximum sterilization fluid exists only in a region where the distance Rout from the outflow center point Oout of the chamber outlet 13 in the sterilization chamber 60 is ¼ or less of the diameter D of the sterilization chamber 60.

Explanation of Signs

[0137] 1: Fluid sterilization device 10: Sterilization chamber body 12: Chamber inlet 13: Chamber outlet 14: Opening for light source 15: Concave groove 20: Light source unit 22: Light-emitting element 30: Housing 31A: Housing supply port 32A: Housing discharge port 60: Sterilization chamber θ5: Half-value angle of the light-emitting element L1: Central axis of the opening for light source L6: Optical axis of the light-emitting element Oout: Outflow center point of the chamber outlet Rout: Distance (radius) from the outflow center point Aout: Partial spherical region D: Diameter of the sterilization chamber

Claims

1. A sterilization chamber body having a fluid sterilization chamber with a concave spherical wall surface, and a light source opening, a chamber inlet for flowing the fluid into the sterilization chamber, and a chamber outlet for flowing the fluid out of the sterilization chamber are formed to open into the sterilization chamber, a light source unit configured to block the light source opening and emit ultraviolet light from the light source opening into the sterilization chamber, the chamber inlet is arranged such that the opening of the chamber inlet faces the surface on the sterilization chamber side of the plane including the light source opening, the chamber outlet is arranged such that the opening of the chamber outlet faces the surface on the sterilization chamber side of the plane including the light source opening, when the integrated irradiation dose of the ultraviolet light on the fluid in the sterilization chamber is divided into seven parts, the fluid corresponding to the maximum integrated irradiation dose among the seven parts is defined as the maximum sterilized fluid, the maximum sterilized fluid is configured to exist only in a region where the distance from the outflow center point of the chamber outlet in the sterilization chamber is ¼ or less of the diameter of the sterilization chamber, a fluid sterilization device.

2. The fluid sterilization device according to claim 1, wherein in a region where the distance from the outflow center point of the chamber outlet in the sterilization chamber is ¼ or less of the diameter of the sterilization chamber, the ratio occupied by the maximum sterilized fluid is 80% or more.

3. The fluid in the sterilization chamber forms a spiral flow, The fluid sterilization device according to claim 1 or 2, wherein the central axis direction of the spiral flow is configured to change from the chamber inlet toward the chamber outlet.

4. The fluid sterilization device according to claim 3, wherein the central axis direction of the spiral flow is configured to change so as to approach the central axis direction of the chamber outlet.

5. The edge line of the light source opening is formed in a circular shape, The fluid sterilization device according to claim 3, wherein the ratio D / d of the diameter D of the sterilization chamber to the diameter d of the light source opening is set in the range of 1.8 to 2.

2.

6. The fluid sterilization device according to claim 1 or 2, wherein when viewed from the central axis direction of the light source opening, at least a part of the opening of the chamber inlet is arranged so as not to overlap the light source opening, and at least a part of the opening of the chamber outlet is arranged so as not to overlap the light source opening.

7. The light source unit includes a light emitting element that emits the ultraviolet light, The light-emitting element is configured to have two maximum illuminance axes that are symmetric with respect to the optical axis in a cross-section passing through the optical axis that is located in the central direction within the spread of the light distribution characteristics, for the fluid sterilization device according to claim 1 or 2.

8. The opening of the chamber inlet is formed smaller than the chamber outlet, for the fluid sterilization device according to claim 1 or 2.

Images