Fluid sterilization device

Abstract

Provided is a fluid sterilization device capable of forming a spiral flow. This fluid sterilization device is provided with: a flow path pipe (100) in which an inflow port (101) is formed on the side wall of a first end side and an outflow port (102) is formed on the second end side; and a light source unit (110) that radiates ultraviolet light toward the second end side. The light source unit has: a light-emitting element that radiates ultraviolet light; a column section (120) provided so as to protrude from the end surface of the first end of the flow path pipe toward the second end side; and a housing section (130) provided at the tip of the column section and housing the light-emitting element, the housing section being formed so as to expand from the tip of the column section to the outside in the radial direction of the column section over the entire circumference of the tip of the column section, the flow path central axis of the flow inlet (101) being parallel to a line intersecting the central axis O of the flow path tube and coincident with the direction not intersecting the central axis O of the flow path tube, and the flow path central axis of the flow inlet (101) being parallel to the line intersecting the central axis O of the flow path tube. The position, shape, and size of the inflow port are configured such that the fluid flowing in from the inflow port (101) surrounds the column portion from the periphery.

Description

Technical Field

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

[0002] There is a known sterilization device that sterilizes and inactivates bacteria and viruses in flowing water by irradiating ultraviolet light. A mercury lamp is widely used as a light source. Since a mercury lamp uses mercury, it is highly toxic and has a problem of a large environmental burden. In addition, when using a mercury lamp, there is also a problem that the size of the sterilization device is large. Therefore, the replacement of mercury lamps with ultraviolet LEDs is being promoted.

[0003] As fluid sterilization devices using ultraviolet LEDs, Patent Documents 1 and 2 exist. Patent Documents 1 and 2 show a structure in which a columnar light source portion protruding from one end of a flow path tube toward the other end side is provided.

[0004] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2022-173327

[0005] Patent Document 2: Japanese Unexamined Patent Application Publication No. 2019-18198

[0006] In order to efficiently sterilize a fluid and reduce pressure loss, it is effective to form a spiral flow in a flow path tube. However, it is difficult to generate a spiral flow in existing fluid sterilization devices. Summary of the Invention

[0007] The present invention has been completed in view of such a background, and an object thereof is to provide a fluid sterilization device capable of forming a spiral flow.

[0008] One aspect of the present invention is a fluid sterilization device including: a flow path tube that forms a flow path space through which a fluid flows, and has a flow inlet formed in a side wall on a first end side and a flow outlet formed on a second end side; and a light source portion that is disposed at a position in the flow path space close to the flow inlet and irradiates ultraviolet light toward the second end side. In the fluid sterilization device, the light source portion includes: a light emitting element that irradiates ultraviolet light; a column portion that is provided to protrude from an end surface of the first end of the flow path tube toward the second end side; and a housing portion that is provided at an end of the column portion and houses the light emitting element. The housing portion is formed to expand radially outward from the end of the column portion over the entire circumference of the end of the column portion. A central axis of a flow path of the flow inlet is parallel to a line that intersects a central axis of the flow path tube and is in a direction that does not intersect the central axis of the flow path tube. A position, shape, and size of the flow inlet are configured such that the fluid flowing in from the flow inlet surrounds the column portion from all around.

[0009] In the fluid sterilization device of the above-described manner, the fluid flowing in from the inlet flows in a manner that surrounds the column portion from all around. Thereafter, the fluid passes through the annular region between the housing portion and the inner wall of the flow path tube. Therefore, a spiral flow can be efficiently formed in the flow path tube. Description of the Drawings

[0010] Figure 1 It is a perspective view showing the structure of the fluid sterilization device of Embodiment 1.

[0011] Figure 2 It is a view showing the structure of the fluid sterilization device of Embodiment 1, and is Figure 1 a cross-sectional view taken along line II-II.

[0012] Figure 3 It is a view showing the structure of the fluid sterilization device of Embodiment 1, and is Figure 1 a cross-sectional view taken along line III-III.

[0013] Figure 4 It is a view showing the structure of the fluid sterilization device of Embodiment 1, and Figure 4 (a) of which is Figure 1 a cross-sectional view taken along line IVa-IVa, Figure 4 (b) of which is a cross-sectional view taken along line IVb-IVb.

[0014] Figure 5 It is a view schematically showing the flow of the fluid near the inlet, and Figure 5 (a) of which is a view showing the side of the first end portion 100a, Figure 5 (b) of which is a view showing the side of the second end portion 100b.

[0015] Figure 6 It is a view schematically showing the structure of the light source portion of the fluid sterilization device of Embodiment 2.

[0016] Figure 7 It is a view schematically showing the structure of the light source portion of the fluid sterilization device of Embodiment 3.

[0017] Figure 8 It is a view schematically showing the structure of the light source portion of the fluid sterilization device of Embodiment 4.

[0018] Figure 9 It is a view schematically showing the structure of the fluid sterilization device of Modified Example 1 of Embodiment 1.

[0019] Figure 10 It is a view schematically showing the structure of the fluid sterilization device of Modified Example 2 of Embodiment 1.

[0020] Description of Reference Numerals

[0021] 100...Flow path tube; 101...Flow inlet; 102...Flow outlet; 110, 110a, 110b, 210, 310, 410, 510...Light source unit; 111...Hole; 120...Column part; 130...Storage part; 132...Glass plate; 133...Base part; 134...Recessed part; 135...Substrate; 136...Peripheral wall; 140...LED package. Detailed implementation mode

[0022] The fluid sterilization device has: a flow path tube that forms a flow path space for fluid to flow, and has a flow inlet formed on the side wall of the first end side and a flow outlet formed on the second end side; and a light source unit that is disposed at a position in the flow path space near the flow inlet and irradiates ultraviolet light toward the second end side. The light source unit has: a light emitting element that irradiates ultraviolet light; a column part that is provided to protrude toward the second end side from the end surface of the first end of the flow path tube; and a storage part that is provided at the end of the column part and houses the light emitting element. The storage part is formed to expand radially outward from the end of the column part over the entire circumference of the end of the column part. The flow path center axis of the flow inlet is parallel to the line intersecting the center axis of the flow path tube and is in the same direction as the direction not intersecting the center axis of the flow path tube. The position, shape, and size of the flow inlet are configured such that the fluid flowing in from the flow inlet surrounds the column part from all around.

[0023] Alternatively, in the above fluid sterilization device, it is configured such that the cross-sectional area S1 perpendicular to the flow path center axis direction of the flow path region of the flow inlet is 0.8 times or more and 1.2 times or less of the cross-sectional area S2 perpendicular to the center axis of the flow path tube of the annular region formed between the storage part and the inner wall surface of the flow path tube. If S1 and S2 are set like this, the flow rate of the fluid flowing at the flow inlet per unit time is approximately equal to the flow rate of the fluid flowing in the above annular region per unit time, and the pressure loss can be reduced.

[0024] Alternatively, in the above fluid sterilization device, the extension line of the flow path center axis of the flow inlet is provided at a position that does not interfere with the light source unit. In addition, it can also be configured such that when viewed from the direction of the flow path center axis of the flow inlet, the ratio of the region where the flow path region of the flow inlet interferes with the light source unit to the flow path region of the flow inlet is 90% or more and 100% or less, and it can also be configured such that when viewed from the axial direction of the flow inlet, the flow path region of the flow inlet does not interfere with the column part. By doing so, the fluid flowing into the flow path tube smoothly flows into the region on the side surface of the column part, and it is easy to form a flow path that rotates around the column part. Therefore, the pressure loss can be reduced. In addition, a spiral flow can be easily formed.

[0025] Alternatively, in the above-described fluid sterilization device, it is configured such that, for a single-sided cross-sectional area S3 in a cross-section including the central axis of the flow path tube in a region surrounded by the side surface of the column portion, the back surface of the housing portion, the extended surface of the back surface of the housing portion, the inner wall surface of the flow path tube, and the end surface of the first end, the cross-sectional area S3 is 0.8 times or more and 1.2 times or less of the cross-sectional area S1 perpendicular to the axial direction of the inlet port with respect to the flow path region of the inlet port. By setting S1 and S3 in this way, the flow rate of the fluid flowing into the flow path tube from the inlet port per unit time is almost equal to the flow rate of the fluid surrounding the column portion per unit time. Therefore, the pressure loss can be reduced.

[0026] Alternatively, in the above-described fluid sterilization device, there is also a second light source unit. The second light source unit is disposed at a position near the outlet port in the flow path space and irradiates ultraviolet light toward the first end side. The outlet port is formed on the side wall on the second end side. The second light source unit includes: a second light emitting element that irradiates ultraviolet light; a second column portion that is provided to protrude toward the first end side from the end surface of the second end of the flow path tube; and a second housing portion that is disposed at the end of the second column portion and houses the second light emitting element. The second housing portion is formed to expand radially outward from the end of the second column portion over the entire circumference of the end of the second column portion. The central axis of the flow path of the outlet port is parallel to the line that intersects the central axis of the flow path tube and is in the same direction as the direction that does not intersect the central axis of the flow path tube. The position, shape, and size of the outlet port are configured such that the fluid flowing out from the outlet port surrounds the second column portion.

[0027] Alternatively, in the above-described fluid sterilization device, it is configured such that the cross-sectional area S4 perpendicular to the flow path central axis direction of the flow path region of the outlet port is 0.8 times or more and 1.2 times or less of the cross-sectional area S5 perpendicular to the central axis of the flow path tube in the annular region formed between the second housing portion and the inner wall surface of the flow path tube.

[0028] Alternatively, in the above-described fluid sterilization device, it is configured such that when viewed from the flow path central axis direction of the outlet port, the ratio of the region where the flow path region of the outlet port interferes with the second light source unit to the flow path region of the outlet port is 90% or more and 100% or less.

[0029] It can also be configured such that, for a single-sided cross-sectional area S6 in a cross-section including the central axis of the flow path tube in a region surrounded by the side surface of the second column portion, the back surface of the second housing portion, the extended surface of the back surface of the second housing portion, the inner wall surface of the flow path tube, and the end surface of the second end, the cross-sectional area S6 is 0.8 times or more and 1.2 times or less of the cross-sectional area S4 perpendicular to the flow path central axis direction of the flow path region of the outlet port.

[0030] (Embodiment 1)

[0031] 1. Outline of the Structure of the Fluid Sterilizing Device 1

[0032] Figure 1 It is a perspective view showing the structure of the fluid sterilizing device 1 of Embodiment 1. As Figure 1 shown, the fluid sterilizing device of Embodiment 1 has a flow path tube 100 and has two light source parts 110 inside it. Figure 1 Among them, the X-axis is taken in the direction of the central axis O of the flow path tube 100, the Y-axis is taken in the direction orthogonal to the X-axis and parallel to the central axis L1 of the inlet, and the Z-axis is taken in the direction perpendicular to the X-axis and the Y-axis.

[0033] Figure 2 It is a cross-sectional view showing the structure of the fluid sterilizing device of Embodiment 1 and is the cross-section (ZX plane) of II-II of Figure 1 it. As Figure 2 shown, inside the flow path tube 100, the light source parts 110 are respectively arranged at both ends of the flow path tube 100. In addition, Figure 3 It is a cross-sectional view showing the structure of the fluid sterilizing device of Embodiment 1 and is a view showing a part (the side of the first end part 100a) of the cross-section (XY plane) of III-III of Figure 1 it. In addition, Figure 4 It is a cross-sectional view showing the structure of the fluid sterilizing device of Embodiment 1, Figure 4 (a) of Figure 1 is the cross-section (YZ plane) at IVa-IVa of Figure 4 (b) of Figure 1 is the cross-section (YZ plane) at IVb-IVb of

[0034] The fluid sterilizing device 1 of Embodiment 1 is a device that allows fluid to flow into the flow path space inside the flow path tube 100 from the inlet 101 of the flow path tube 100, irradiates the fluid with ultraviolet light from the light source part 110 to sterilize the fluid, and discharges the sterilized fluid from the outlet 102. The fluid to be sterilized can be either a gas or a liquid, and as long as it is within the range of having fluidity, it can also be a mixture of gas and liquid, a mixture of gas and powdery solid, etc. In the case of a liquid, for example, it is water, oil, alcohol, a solution dissolved in them as a solvent, etc.

[0035] 2. Details of Each Structure of the Fluid Sterilizing Device 1

[0036] Next, each structure of the fluid sterilizing device 1 of Embodiment 1 will be described in detail.

[0037] 2-1. Structure of the Flow Path Tube 100

[0038] The flow path tube 100 is cylindrical and has a cylindrical space inside. This space is a flow path space for the fluid to be sterilized to flow. Light source parts 110 are provided at both ends respectively. Here, one end of the flow path tube 100 is taken as the first end 100a, the other end is taken as the second end 100b, the light source part 110 provided on the side of the first end 100a among the two light source parts 110 is taken as the light source part 110a, and the light source part 110 provided on the side of the second end 100b is taken as the light source part 110b. In addition, a fluid inlet 101 is provided on the side wall of the flow path tube 100 near the first end 100a, and a fluid outlet 102 is provided on the side wall near the second end 100b. The fluid inlet 101 and the fluid outlet 102 are cylindrical and have a flow path area for the fluid to flow.

[0039] The material of the flow path tube 100 is SUS, titanium, PTFE (polytetrafluoroethylene), etc. It is also possible to cover the inner wall surface of a resin material that is resistant to ultraviolet light with a material having a high ultraviolet light reflectivity. The resin material resistant to ultraviolet light is, for example, vinyl chloride. In addition, the material with a high ultraviolet light reflectivity is aluminum, PTFE, etc. In addition, it is also possible to cover the outer wall surface of a material that transmits ultraviolet light with a material having a high ultraviolet light reflectivity. The material that transmits ultraviolet light is, for example, sapphire, ultraviolet-transmitting glass, fluororesin, acrylic resin, etc.

[0040] The arithmetic mean roughness (arithmetic mean deviation) Ra of the inner wall surface of the flow path tube 100 is preferably 0.2 nm to 10 μm. The resistance of the inner wall surface is reduced, and it becomes easier to maintain the flow. More preferably, it is 0.2 nm to 3 μm, and further preferably, it is 0.2 nm to 1 μm.

[0041] As Figure 4 shown in (a) of Figure 4 , the fluid inlet 101 is arranged such that the inflow direction of the fluid flowing in from the fluid inlet 101 is offset with respect to the central axis O of the flow path tube 100. In other words, the central axis of the flow path area of the fluid inlet 101, that is, the flow path central axis (hereinafter only referred to as the central axis of the fluid inlet 101) L1, is parallel to the line intersecting the central axis O of the flow path tube 100 and is in the same direction as not intersecting the central axis O of the flow path tube 100. When observed in a sectional view as shown in (a) of Figure 2 , the central axis L1 of the fluid inlet 101 is offset by Y1 in the Y direction with respect to the central axis O so as not to pass through the central axis O of the flow path tube 100. In this way, by offsetting the position of the fluid inlet 101, a spiral flow can be formed in the flow path space in the flow path tube 100, and the tangential direction of the spiral flow becomes the direction of the central axis L1 of the fluid inlet 101. In addition, as Figure 2 shows, the angle formed by the central axis L1 of the fluid inlet 101 and the central axis O is 90 degrees. Although it is not necessarily 90 degrees, it is preferably 80 degrees to 100 degrees.

[0042] As shown in Figure 4 (b) of FIG. Figure 4 , the outlet 102 is also arranged with its outflow direction offset relative to the central axis O of the flow path tube 100. In other words, the central axis of the flow path region of the outlet 102, that is, the flow path central axis (hereinafter only referred to as the central axis of the outlet 102) L2, is parallel to the line intersecting the central axis O of the flow path tube 100 and is in the same direction as not intersecting the central axis O of the flow path tube 100. When observing in a sectional view as in

[0043] (b) of FIG.

[0044] 2-2. Structure of the light source unit 110

[0045] The light source unit 110 includes an LED package 140, a column part 120, and a housing part 130. Hereinafter, the light source unit 110a provided on the first end part 100a side will be described, but the light source unit 110b provided on the second end part 100b side has the same structure.

[0046] As shown in Figure 1 FIG.

[0047] , the column part 120 protrudes from the first end of the flow path tube 100 toward the second end side and has a frustum cone-shaped part. The central axis of the column part 120 coincides with the central axis of the flow path tube 100. The inclination angle of the side surface of the frustum cone (angle relative to the bottom surface) is, for example, 30° to 70°. One end of the column part 120 with a thicker diameter is connected to the first end of the flow path tube 100, and one end with a thinner diameter is connected to the housing part 130. Figure 1 In addition, the shape of the column part 120 is not limited to the frustum cone shape. As long as it is a shape that becomes thinner as it approaches the second end side, the column part 120 can be any shape. It can also be a shape that becomes thinner in stages, but a continuously thinning shape is preferred. For example, it can also be a frustum pyramid shape. However, a frustum cone shape is preferred for forming a spiral flow. In addition, the whole of the column part 120 may not be a frustum cone, or a part of the column part 120 may be a frustum cone and other parts may be a cylinder. For example, as shown in

[0048] The storage part 130 is connected to the end of the column part 120. The storage part 130 stores the LED package 140. The storage part 130 has a glass plate 132, a pedestal part 133, and a substrate 135.

[0049] The pedestal part 133 is a cylindrical box-shaped body with an open upper surface, and its outer bottom surface is connected to the end of the column part 120. The substrate 135 is disposed on the bottom surface inside the box, and the LED package 140 is mounted on the substrate 135. The glass plate 132 is provided on the upper surface of the box to seal the inside of the box. The glass plate 132 is a material that allows ultraviolet light from the LED package 140 to pass through, such as quartz or sapphire. Alternatively, a photocatalyst film that allows ultraviolet light to pass through may be provided on the surface of the glass plate 132 to inhibit the growth of miscellaneous bacteria at the glass plate 132 or prevent organic contamination. The glass plate 132 is not limited to a flat plate and may also be lens-shaped. For example, it may be a TIR lens, a compound eye lens, a Fresnel lens, etc.

[0050] As Figure 1 shown, the pedestal part 133 is formed to expand radially outward from the end of the column part 120 over the entire circumference of the end of the column part 120. Therefore, except for the area connected to the column part 120, the back surface of the pedestal part 133 is in contact with the flow path space.

[0051] The pedestal part 133 has a peripheral wall 136 protruding toward the first end side in the outer peripheral area of its back surface, and has a recess 134 surrounded by the back surface of the pedestal part 133 and the peripheral wall 136. In addition, in Embodiment 1, it is necessary to provide the peripheral wall 136 over the entire circumference, and it is preferably provided locally. If it is provided over the entire circumference, air cavities are formed in the recess 134, deteriorating the cooling efficiency. In addition, preferably, when viewed from the central axis direction of the flow path tube 100, the peripheral wall 136 is provided outside the LED package 140. In other words, it is preferred that the LED package 140 is located within the area of the recess 134. The pedestal part 133 can be cooled more efficiently.

[0052] In addition, in Embodiment 1, the pedestal part 133 is a cylindrical box-shaped body, but it may be any shape as long as it is box-shaped. For example, it may also be a regular quadrangular prism-shaped box (hopper-shaped). However, from the aspect of generating a spiral flow, it is preferably a cylindrical box-shaped body as in Embodiment 1.

[0053] The materials of the column part 120 and the pedestal part 133 are preferably high-dissipation resins mixed with metal materials with high thermal conductivity such as SUS and aluminum and thermal conductive fillers. In addition, it may also be that titanium is used and the surface is oxidized to form a photocatalyst film. This can inhibit the growth of miscellaneous bacteria on the column part 120 and the pedestal part 133.

[0054] The LED package 140 is mounted on the substrate 135. Multiple LED packages 140 can also be mounted. Figure 1 Two are mounted. The LED package 140 has an LED, a substrate on which the LED is mounted, and a lens that seals the LED.

[0055] The LED is a light-emitting element that emits ultraviolet light. Preferably, the wavelength of the ultraviolet light is a wavelength with high sterilization efficiency, that is, 250 nm to 285 nm. It is also possible that multiple LEDs are provided in one LED package 140.

[0056] Preferably, when viewed from the central axis direction of the flow path tube 100, the LED package 140 is mounted in a region outside the column portion 120. Since the fluid can contact the region directly below the LED package 140 on the back surface of the pedestal portion 133, the storage portion 130 can be efficiently cooled.

[0057] In addition, in Embodiment 1, the encapsulated LED package 140 is mounted on the substrate 135, but the LED can also be directly mounted on the substrate 135.

[0058] A series of through holes 111 are provided in the center of the column portion 120 and the storage portion 130. The holes 111 are holes through which wiring cables for supplying power to the LED package 140 and circuit components on the mounting substrate pass. The wiring cables are introduced into the mounting substrate through the holes 111.

[0059] 3. Positions, shapes, and sizes of the inlet 101 and the outlet 102

[0060] The position, shape, and size of the inlet 101 are configured such that the fluid flowing in from the inlet 101 surrounds the column portion 120 from all sides. Thus, it becomes easier to form a spiral flow of the fluid. Specifically, it is preferable to set the position, shape, and size of the inlet 101 in a manner that satisfies the following.

[0061] As Figure 3 shown, the cross-sectional area of the flow path region of the inlet 101 in the cross-section perpendicular to the central axis L1 of the inlet 101 is set as S1. In addition, as Figure 4 (a) of shows, the cross-sectional area in the direction perpendicular to the central axis O of the flow path tube 100 of the annular region between the storage portion 130 for the light source portion 110a and the inner wall surface of the flow path tube 100 is set as S2.

[0062] At this time, it is preferably configured such that S1 is 0.8 times or more and 1.2 times or less of S2. More preferably, S1 is 0.9 times or more and 1.1 times or less of S2.

[0063] By configuring S1 and S2 in this way, the flow rate of the fluid flowing into the flow path tube 100 from the inlet 101 per unit time is almost equal to the flow rate of the fluid passing through the annular region per unit time. Therefore, the pressure loss can be reduced.

[0064] In addition, as Figure 3 shown, it is preferable that the extension line of the central axis L1 of the inlet 101 is set at a position where it does not interfere with the light source unit 110a. In addition, when viewed from the direction of the central axis L1 of the inlet 101, the ratio of the region where the flow path region of the inlet 101 interferes with the light source unit 110a to the flow path region of the inlet 101 is preferably 90% or more. More preferably, it is 95% or more.

[0065] By setting in this way, the fluid flowing into the flow path tube 100 smoothly flows into the region on the side surface of the column part 120, and it is easy to form a flow path that rotates around the column part 120. Therefore, the pressure loss can be reduced. In addition, a spiral flow can be easily formed.

[0066] As Figure 3 shown, the cross-sectional area of one side cross-section in the plane including the central axis O of the flow path tube 100 of the region surrounded by the side surface of the column part 120, the back surface of the storage part 130, the extended surface of the back surface of the storage part 130, the inner wall surface of the flow path tube 100, and the end surface of the flow path tube 100 on the side of the first end part 100a is set as S3. At this time, it is preferably configured such that S3 is 0.8 times or more and 1.2 times or less of S1. More preferably, S3 is 0.9 times or more and 1.1 times or less of S1.

[0067] By configuring S1 and S3 in this way, the flow rate of the fluid flowing into the flow path tube 100 from the inlet 101 per unit time is almost equal to the flow rate of the fluid surrounding the column part 120 per unit time. Therefore, the pressure loss can be reduced.

[0068] In addition, although the setting of the position, shape, and size of the inlet 101 has been described above, it is preferable to set the position, shape, and size of the outlet 102 in the same way. In other words, the position, shape, and size of the outlet 102 can also be configured such that the fluid flowing out from the outlet 102 surrounds the column part 120 from all around. In addition, it is also possible that the shapes and sizes are different at the inlet 101 and the outlet 102.

[0069] In addition, as long as it is within the range satisfying the above content, the cross-sectional shape of the flow path regions of the inlet 101 and the outlet 102 may not be circular, but in order to further reduce the pressure loss, it is preferably circular.

[0070] 4. Regarding the flow path of the fluid

[0071] Refer to Figure 5The flow path of the fluid flowing in the flow path tube 100 will be described. Figure 5 Fig. (a) schematically shows the flow path on the first end 100a side (fluid inlet 101 side) of the flow path tube 100. Figure 5 Fig. (b) schematically shows the flow path on the second end 100b side (fluid outlet 102 side) of the flow path tube 100.

[0072] As Figure 5 shown in Fig. (a), the fluid that enters the flow path space in the flow path tube 100 from the fluid inlet 101 flows in a manner that surrounds the column portion 120 of the light source portion 110a from all around. This is because the fluid inlet 101 is offset with respect to the central axis O of the flow path tube 100, and the position, shape, and size of the fluid inlet 101 are set to surround the column portion 120 from all around. When observed in the direction from the first end 100a toward the second end 100b along the central axis O of the flow path tube 100, the fluid flows in a counterclockwise rotation manner.

[0073] The fluid that surrounds the column portion 120 from all around impinges on the side surface of the frustum-shaped portion of the column portion 120. Therefore, the fluid is reflected axially due to the inclination of the side surface, and a flow path toward the storage portion 130 is formed. Therefore, the fluid can efficiently contact the storage portion 130, and an improvement in cooling efficiency can be achieved.

[0074] In addition, the pedestal portion 133 is formed to expand radially outward from the end of the column portion 120 over the entire circumference of the end of the column portion 120. Therefore, the fluid can contact the back surface of the pedestal portion 133. In particular, the fluid contacts the region of the back surface of the pedestal portion 133 that corresponds to directly below the LED package 140. Therefore, the pedestal portion 133 can be efficiently cooled.

[0075] In addition, a peripheral wall 136 is provided on the back surface of the pedestal portion 133, and there is a recessed portion 134 surrounded by the peripheral wall 136. Therefore, the fluid easily stays on the back surface of the pedestal portion 133. Therefore, heat can be efficiently conducted from the back surface of the pedestal portion 133 to the fluid, and an improvement in cooling efficiency can be achieved.

[0076] Thereafter, in the annular region between the storage portion 130 and the inner wall surface of the flow path tube 100, the fluid flows in the central axis direction while rotating around the central axis O. As a result, a spiral flow F1 is formed. By forming the spiral flow F1, the residence time of the fluid in the flow path space becomes longer, and the irradiation time of ultraviolet light to the fluid becomes longer. Therefore, an improvement in sterilization efficiency can be achieved.

[0077] On the other hand, on the second end 100b side, as Figure 5As shown in (b) thereof, the spiral flow F2 is maintained. This is because a regular spiral flow F1 is formed on the first end 100a side. Therefore, even at a distance, the disruption of the spiral flow F1 is small. As a result, on the second end 100b side, the irradiation time of ultraviolet light is also longer, and an improvement in sterilization efficiency can be achieved.

[0078] In addition, on the second end 100b side, in the annular region between the housing portion 130 of the light source portion 110b and the inner wall surface of the flow path tube 100, the fluid also passes in the direction of the central axis O while rotating around the central axis O. Moreover, the fluid flows out from the outlet 102 while surrounding the column portion 120 of the light source portion 110b from all around. Similar to the inlet 101, the outlet 102 is also offset with respect to the central axis O of the flow path tube 100, and the position, shape, and size of the outlet 102 are set to surround the column portion 120 from all around. Therefore, the fluid can flow out smoothly from the outlet 102, and the pressure loss can be reduced.

[0079] In addition, a part of the fluid surrounding the column portion 120 of the light source portion 110b from all around is reflected by the side surface of the column portion 120 to form a flow path F0 toward the housing portion 130 of the light source portion 110b. Therefore, the housing portion 130 of the light source portion 110b can be efficiently cooled.

[0080] 5. Summary

[0081] As described above, in the fluid sterilization device of Embodiment 1, the flow path direction of the inlet 101 is made to be the same as the direction toward a position offset with respect to the central axis O of the flow path tube 100. Further, the position, shape, and size of the inlet 101 are configured such that the fluid flowing in from the inlet 101 surrounds the column portion 120 from all around. In addition, the housing portion 130 is formed to expand radially outward from the end of the column portion 120 over the entire circumference of the end of the column portion 120. Therefore, an annular region is formed between the housing portion 130 of the light source portion 110 and the inner wall surface of the flow path tube 100. The fluid passes through this annular region while rotating around the axis. As a result, a regular spiral flow can be easily formed.

[0082] (Embodiment 2)

[0083] Figure 6 is a diagram schematically showing the structure of the light source portion 210 of the fluid sterilization device of Embodiment 2. As Figure 6As shown in (a), the light source unit 210 includes a column portion 220 and a housing portion 230. The column portion 220 has the same structure as the column portion 120 in Embodiment 1. The housing portion 230 has a structure in which the pedestal portion 133 of the housing portion 130 in Embodiment 1 is replaced with a pedestal portion 233, and the other structures are the same as those of the housing portion 130. The pedestal portion 233 has a structure in which the peripheral wall 136 is removed from the pedestal portion 133, and the outer peripheral region of the back surface of the pedestal portion 233 is flat.

[0084] In Embodiment 2, although the effect of retaining the fluid on the back surface of the housing portion 230 by the peripheral wall 136 cannot be obtained, other effects are obtained in the same manner as in Embodiment 1.

[0085] Alternatively, in Embodiment 2, in the light source unit 210 on the side of the inflow port 101, a groove 237 may be provided on the back surface of the housing portion 230 (the back surface of the pedestal portion 233) to guide the fluid from the center side to the outer peripheral side of the back surface of the housing portion. Or, instead of the groove 237, a wall-like protrusion may be provided.

[0086] Figure 6 (b) and (c) show Figure 6 A cross-sectional view taken along line VI-VI of (a). Figure 6 In (b), a spiral groove 237 is provided on the back surface of the pedestal portion 233. The center of the spiral is the center of the column portion 220. By providing such a spiral groove 237, the contact time of the fluid with the housing portion 230 becomes longer, and thus cooling can be performed efficiently. In addition, a flow path can be formed such that the fluid swirls toward the outer periphery of the back surface of the housing portion 230, and the fluid passing between the inner wall of the flow path tube 100 and the housing portion 230 easily forms a spiral flow.

[0087] Figure 6 In (c), a radial groove 237 is provided on the back surface of the pedestal portion 233. By providing such a groove 237, the fluid can be guided to the outer periphery.

[0088] Alternatively, in the light source unit 210 on the side of the outflow port 102, the groove 237 may also be provided as in Figure 6 (b) and (c). The housing portion 230 can be cooled efficiently. In addition, the fluid that has passed between the inner wall of the flow path tube 100 and the housing portion 230 can be guided toward the column portion 220 side, and thereafter, a smooth flow path can be formed toward the outflow port 102 side due to the reflection by the column portion 220.

[0089] (Embodiment 3)

[0090] Figure 7This is a diagram schematically showing the structure of the light source unit 410 of the fluid sterilization device according to Embodiment 3. The light source unit 410 has a column portion 420 and a storage portion 130. As Figure 7 shown, the column portion 420 is cylindrical. The structure other than this is the same as that of the column portion 120 in Embodiment 1. The storage portion 130 is the same as that in Embodiment 1.

[0091] In Embodiment 3, since the column portion 420 is cylindrical, it does not have the effect of causing the fluid to flow toward the storage portion 430 side, but the other effects are obtained in the same manner as in Embodiment 1.

[0092] (Embodiment 4)

[0093] Figure 8 This is a diagram schematically showing the structure of the light source unit 510 of the fluid sterilization device according to Embodiment 4. The light source unit 510 has a column portion 420 and a storage portion 230. The column portion 420 is the same as the column portion 420 in Embodiment 3 and is cylindrical. The storage portion 230 has the same structure as the storage portion 230 in Embodiment 2 and has a structure in which there is no peripheral wall 136 in the outer peripheral region on the back surface of the pedestal portion 233.

[0094] In Embodiment 4, it does not have the effect of causing the fluid to flow toward the storage portion 230 side or the effect of causing the fluid to stay on the back surface of the storage portion 230, but the other effects are obtained in the same manner as in Embodiment 1.

[0095] In addition, in Embodiment 4, it may be the same as (b) and (c) in Figure 6 of Embodiment 2, and a groove is provided on the back surface of the storage portion 230 to guide the fluid from the center side to the outer peripheral side on the back surface of the storage portion.

[0096] (Modification 1 of Embodiment 1)

[0097] Figure 9 This is a diagram schematically showing the structure of the fluid sterilization device according to Modification 1 of Embodiment 1. As Figure 9 shown, the fluid sterilization device according to Modification 1 has a light intensity sensor 600 at the central portion of the flow path tube 100. The structure other than this is the same as that of the fluid sterilization device in Embodiment 1.

[0098] The light intensity sensor 600 is a sensor that detects the intensity of ultraviolet light at the central portion inside the flow path tube 100. For example, the outputs of the two light source units 110 are controlled so that the intensity of ultraviolet light at the central portion becomes a predetermined value or more.

[0099] In addition, the light intensity sensor 600 also serves as a rectifying plate. The light intensity sensor 600 is a wall-like protrusion provided on the inner wall of the flow path tube 100 and protruding toward the central axis side of the flow path tube 100. The light intensity sensor 600 is in the shape of a wall along the direction of the spiral flow. Thus, the spiral flow is maintained at the central portion of the flow path tube 100.

[0100] (Modification 2 of Embodiment 1)

[0101] Figure 10 FIG. schematically shows the structure of the fluid sterilization device according to Modification 2 of Embodiment 1. As Figure 10 shown, the fluid sterilization device according to Modification 2 has a structure in which a spiral groove 700 is provided on the inner wall of the flow path tube 100, and the other structures are the same as those of the fluid sterilization device according to Embodiment 1. By providing the spiral groove 700 in the flow path tube 100, it becomes easier to maintain the spiral flow in the flow path space, and an improvement in sterilization efficiency can be achieved.

[0102] (Other Modifications)

[0103] The fluid sterilization devices of Embodiments 1 to 5 are each provided with a light source unit 110 on the inlet side 101 and the outlet side 102 of the flow path, but it is also possible to provide the light source unit 110 only on the inlet side 101, for example, when the flow path tube 100 is short. In this case, a reflection member that reflects ultraviolet light is disposed on the end face on the second end side, and the sterilization efficiency can be improved by irradiating the fluid with the reflected light of the ultraviolet light generated by the reflection member. In addition, it is also possible to provide the light source unit 110 only on the outlet side 102 of the flow path. In this case as well, the sterilization efficiency can be improved by providing a reflection member on the end face on the first end side. As the reflection member, PTFE, SUS, Ti, etc. can be used. In addition, resins such as vinyl chloride coated with fluorine can also be used.

Claims

1. A fluid sterilizing device, comprising: a flow path tube, which forms a flow path space for fluid flow, and has an inlet formed on a side wall of a first end side and an outlet formed on a second end side; and a light source portion, which is arranged in the flow path space at a position close to the inlet and radiates ultraviolet light toward the second end side, The fluid sterilization device is characterized in that: The light source unit comprises: a light emitting element that radiates ultraviolet light; a column portion provided to protrude from an end surface of the first end of the flow tube toward the second end; and a storage portion, which is disposed at the end of the column portion and accommodates the light emitting element, The housing portion is formed to expand from the distal end of the column portion toward the radially outer side of the column portion over the entire circumference of the distal end of the column portion. The central axis of the flow path of the inlet is parallel to a line intersecting the central axis of the flow path pipe and is aligned with a direction not intersecting the central axis of the flow path pipe. The position, shape, and size of the inlet are configured so that the fluid flowing in from the inlet surrounds the column portion from all sides.

2. The fluid sterilization device according to claim 1, characterized in that: The fluid sterilization device is constructed so that a cross-sectional area S1 of the flow path region of the inlet, which is perpendicular to the central axis of the flow path of the inlet, is greater than 0.8 times and less than 1.2 times a cross-sectional area S2 of the annular region formed between the storage portion and the inner wall surface of the flow path tube, which is perpendicular to the central axis of the flow path tube.

3. The fluid sterilization device according to claim 1, characterized in that: An extension line of a central axis line of a flow path of the inlet is disposed at a position that does not interfere with the light source.

4. The fluid sterilization device according to claim 1, characterized in that: The fluid sterilizing device is configured such that, when viewed from the central axis direction of the flow path of the inlet, the area where the flow path of the inlet interferes with the light source accounts for 90% or more and 100% or less of the flow path of the inlet.

5. The fluid sterilization device according to claim 4, characterized in that: The fluid sterilizing device is configured so that, when viewed from the center axis direction of the flow path of the inlet, the flow path region of the inlet does not interfere with the column portion.

6. The fluid sterilization device according to claim 1, characterized in that: The fluid sterilization device is constructed so that a cross-sectional area S3 of a single-side cross-section in a cross-section including a central axis of the flow tube in an area enclosed by the side surface of the column, the back surface of the storage portion, an extended surface of the back surface of the storage portion, the inner wall surface of the flow tube, and the end surface of the first end is greater than 0.8 times and less than 1.2 times a cross-sectional area S1 of the flow path area of ​​the inlet that is perpendicular to the central axis of the flow path of the inlet.

7. The fluid sterilization device according to claim 1, characterized in that: further comprising a second light source portion, the second light source portion being disposed in the flow path space at a position close to the outflow port and radiating ultraviolet light toward the first end side, The outflow port is formed on the side wall of the second end. The second light source unit has: a second light emitting element radiating ultraviolet light; a second column portion, which is provided to protrude from the end surface of the second end of the flow tube toward the first end side; as well as a second housing portion, which is disposed at the end of the second column portion and accommodates the second light emitting element; The second housing portion is formed to expand from the distal end of the second column portion to the radially outer side of the second column portion over the entire circumference of the distal end of the second column portion. The flow path center axis of the outflow port is parallel to a line intersecting the center axis of the flow path tube and is aligned with a direction that does not intersect the center axis of the flow path tube. The position, shape and size of the outflow port are configured so that the fluid flowing out of the outflow port surrounds the column portion from all sides.

8. The fluid sterilization device according to claim 7, characterized in that: The fluid sterilization device is configured so that a cross-sectional area S4 of the flow path region of the outflow outlet, which is perpendicular to the central axis of the flow path of the outflow outlet, is greater than 0.8 times and less than 1.2 times a cross-sectional area S5 of an annular region formed between the second housing portion and the inner wall surface of the flow path tube, which is perpendicular to the central axis of the flow path tube.

9. The fluid sterilization device according to claim 7, characterized in that: The fluid sterilizing device is configured such that, when viewed from the flow path center axis direction of the outflow port, the area where the flow path region of the outflow port interferes with the second light source accounts for 90% or more and 100% or less of the flow path region of the outflow port.

10. The fluid sterilization device according to claim 7, characterized in that: The fluid sterilization device is constructed so that the cross-sectional area S6 of a single-side cross-section in a cross-section including the central axis of the flow tube in an area enclosed by the side surface of the second column portion, the back surface of the second housing portion, the extended surface of the back surface of the second housing portion, the inner wall surface of the flow tube, and the end surface of the second end is greater than 0.8 times and less than 1.2 times the cross-sectional area S4 of the flow path area of ​​the outflow outlet and perpendicular to the direction of the central axis of the flow path of the outflow outlet.

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