Fluid sterilization device

Abstract

To provide a fluid sterilizer for sterilizing fluid such as water by irradiated with ultraviolet light, which suppresses manufacturing cost while using a fluororesin as a material of a flow channel pipe where the fluid flows.SOLUTION: There is provided a fluid sterilizer 1 wherein a flow channel part 10 has a first part 11 having an annular cross section in a radial direction, and a second part 12 having an outflow port 103, the first part 11 is formed of a fluororesin for reflecting ultraviolet light emitted from an ultraviolet light irradiation module 14, the ultraviolet light irradiation module 14 is mounted on the second part 12, a reflecting material 17 which reflects ultraviolet light emitted from the ultraviolet light irradiation module 14 and is composed of a fluororesin is provided on the inner surface of the second part 14 as an inner wall of a flow channel 101, and the reflecting material 17 has a hole 171 where the fluid passes.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Conventionally, a fluid sterilization device that sterilizes fluids such as water by irradiating them with ultraviolet light is known (see, for example, Patent Document 1). The fluid sterilization device of Patent Document 1 includes a housing having a flow path through which the fluid to be sterilized flows in the axial direction, an inlet through which the fluid flows, and an outlet through which the fluid flows out, with the inlet provided at one axial end of the housing and a light source module device that emits ultraviolet light attached to the other end of the housing.

[0003] The wavelength of the ultraviolet light emitted by the light source module device is 240 to 380 nm, and stainless steel is listed as a material for the housing whose inner surface is irradiated with the ultraviolet light. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-89462 Summary of the Invention [Problem to be solved by the invention]

[0005] In a fluid sterilizer such as that described in Patent Document 1, the housing, the inner surface of which is irradiated with ultraviolet light, is required to be made of a material such as fluororesin that has excellent resistance and reflectance to ultraviolet light.

[0006] However, fluororesins are expensive materials. In particular, PTFE (polytetrafluoroethylene), a fluororesin with excellent reflectivity for ultraviolet light in the UV-C wavelength range (less than 280 nm), which has a high sterilizing effect, has a very high melt viscosity and cannot be processed by conventional melt processing. To process it into the desired shape, it must be cut from a block produced by compressing and baking PTFE powder, resulting in very high material and processing costs.

[0007] Therefore, in a fluid sterilization device such as that described in Patent Document 1, if the housing material is simply replaced with fluororesin, the sterilization efficiency will increase because the reflectivity of the housing to ultraviolet light will be higher, but the manufacturing cost will be very high.

[0008] An object of the present invention is to provide a fluid sterilization device that sterilizes fluids such as water by irradiating them with ultraviolet light, which uses fluororesin as the material for the flow path pipes through which the fluid flows, yet has low manufacturing costs. [Means for solving the problem]

[0009] In order to achieve the above object, one aspect of the present invention provides the following fluid sterilization device.

[0010] [1] A fluid sterilization device comprising: a flow path for flowing a fluid to be sterilized, a flow path section having an inlet for allowing the fluid to flow into the flow path, and an outlet for allowing the fluid to flow out of the flow path; and an ultraviolet light irradiation module for irradiating ultraviolet light into the flow path, wherein the flow path section has a first section having a circular radial cross section and a second section having the inlet or the outlet, the first section being made of a fluororesin that reflects the ultraviolet light emitted from the ultraviolet light irradiation module, the ultraviolet light irradiation module being attached to the second section, and a reflective material made of a fluororesin that reflects the ultraviolet light emitted from the ultraviolet light irradiation module being provided along the inner surface of the second section, which forms the inner wall of the flow path, and the reflective material having holes through which the fluid passes. [2] A fluid sterilization device comprising: a flow path for flowing a fluid to be sterilized, a flow path section having an inlet for allowing the fluid to flow into the flow path, and an outlet for allowing the fluid to flow out of the flow path; and an ultraviolet light irradiation module for irradiating ultraviolet light into the flow path, wherein the flow path section has a first section having a circular radial cross section and a second section having the inlet or the outlet, the first section being made of a fluororesin that reflects the ultraviolet light emitted from the ultraviolet light irradiation module, the ultraviolet light irradiation module being attached to the second section, and a reflective material made of a fluororesin that reflects the ultraviolet light emitted from the ultraviolet light irradiation module being provided along the inner surface of the second section, which forms the inner wall of the flow path, and the reflective material being installed in a cylindrical region between the ultraviolet light irradiation module and the first section within the second section. [3] A fluid sterilization device as described in [1] above, wherein the area of ​​the hole is larger than the area of ​​the inlet and the outlet. [4] A fluid sterilization device according to any one of [1] to [3] above, wherein the second part has the outlet, and the end of the first part opposite to the end on the second part side is covered with a flat diffusion plate having a hole through which the fluid passes at a position away from the center thereof, which diffuses the fluid flowing in from the inlet, and the diffusion plate is made of a fluororesin that reflects ultraviolet light emitted from the ultraviolet light irradiation module. [Effects of the Invention]

[0011] According to the present invention, a fluid sterilization device that sterilizes fluids such as water by irradiating them with ultraviolet light can be provided, in which a fluororesin is used as the material for the flow path pipe through which the fluid flows, yet the manufacturing cost of the fluid sterilization device can be reduced. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view of a fluid sterilizing device according to an embodiment of the present invention. [Figure 2] 2(a) and 2(b) are side views of the fluid sterilizing device as seen from the longitudinal direction and from the direction perpendicular to the longitudinal direction, respectively. [Figure 3] FIG. 3 is a cross-sectional view of the fluid sterilization device taken along section line AA shown in FIG. 2(a). [Figure 4] FIG. 4(a) is a plan view of a reflecting material made of a rectangular sheet, and FIG. 4(b) is a perspective view of the reflecting material made of a rectangular sheet rolled into a ring shape. [Figure 5] 5(a) and 5(b) are a plan view and a cross-sectional view of an example of a diffusion plate. [Figure 6] 6(a) and 6(b) are a plan view and a cross-sectional view of another example of the diffusion plate. DETAILED DESCRIPTION OF THE INVENTION

[0013] [Embodiment] (Configuration of fluid sterilization device) Figure 1 is a perspective view of a fluid sterilization device 1 according to an embodiment of the present invention. Figures 2(a) and 2(b) are a side view of the fluid sterilization device 1 as seen from the longitudinal direction and from a direction perpendicular to the longitudinal direction, respectively. Figure 3 is a cross-sectional view of the fluid sterilization device 1 taken along the cutting line AA shown in Figure 2(a).

[0014] The fluid sterilization device 1 is a device for sterilizing fluids (mainly liquids such as water) and suppressing bacterial growth, and is equipped with a flow path 101 for flowing the fluid to be sterilized, a flow path pipe 10 having an inlet 102 for allowing the fluid to flow into the flow path 101, and an outlet 103 for allowing the fluid to flow out of the flow path 101, and an ultraviolet light irradiation module 14 for irradiating ultraviolet light into the flow path 101.

[0015] The flow path pipe 10 has a cylindrical first portion 11, a second portion 12 having an outlet 103 connected to one end of the first portion 11, and a third portion 13 having an inlet 102 connected to the other end of the first portion 12. Here, the inner surfaces of the first portion 11, the second portion 12, and the third portion 13, mainly the inner surfaces of the first portion 11 and the second portion 12, form the inner wall of the flow path 101.

[0016] The first portion 11 is made of a fluororesin that reflects the ultraviolet light emitted from the ultraviolet light irradiation module 14. Therefore, the light emitted from the ultraviolet light irradiation module 14 can be efficiently reflected by the inner surface of the first portion 11 that constitutes the inner wall of the flow path 101. Here, the fluororesin used as the material for the first portion 11 is a fluororesin that has high resistance and reflectance to ultraviolet light, such as PTFE, PFA (perfluoroalkoxyalkane), PVF (polyvinyl fluoride), or PVDF (polyvinylidene fluoride), and is usually white in color.

[0017] In particular, by using PTFE, which has excellent reflectivity for ultraviolet light in the UV-C wavelength range (less than 280 nm) (hereinafter referred to as UVC light), as the material for the first part 11, sterilization can be effectively performed using an ultraviolet light irradiation module 14 that emits UVC light.

[0018] The first portion 11 has a simple cylindrical shape, and therefore can be made of a commercially available general-purpose fluororesin pipe or the like without modification. In order to further reduce the number of processing steps for general-purpose products such as pipes, the first portion 11 preferably has a cylindrical shape with no irregularities on its inner or outer surfaces.

[0019] The second section 12 has a mounting portion 121 for mounting the ultraviolet light irradiation module 14, and an outlet 103. In addition, a sheet-like reflecting material 17 made of fluororesin that reflects ultraviolet light emitted from the ultraviolet light irradiation module 14 is provided along the inner surface of the second section 12, which becomes the inner wall of the flow path 101.

[0020] The second part 12 has an opening 123 for connecting to the first part 11, and the first part 11 and the second part 12 are connected by fitting one end of the first part 11 into the inside of the opening 123. Here, to prevent fluid from leaking from the interface between the first part 11 and the second part 12, it is preferable to use a sealing member such as an O-ring 201 at the overlapping part of the first part 11 and the second part 12.

[0021] The ultraviolet light irradiation module 14 is attached to the second section 12, for example, by screwing a heat sink 146 and a cover 147 of the ultraviolet light irradiation module 14 (described later) to an attachment section 121 of the second section 12 using screws 148. Light emitted from the ultraviolet light irradiation module 14 passes through an opening 122 included in the attachment section 121 and is irradiated onto the fluid in the flow path 101. Note that the opening 122 is blocked by the ultraviolet light irradiation module 14, and water does not leak out from the opening 122.

[0022] 1 to 3, the outflow pipe 16 is connected to the opening 124 of the second part 12 on the outlet 103 side. The outflow pipe 16 is fitted into and fixed to the inside of the opening 124, and the opening of the outflow pipe 16 on the opposite side to the opening 124 functions as the outflow port 103. In this case, in order to effectively prevent fluid from leaking from the interface between the second part 12 and the outflow pipe 16, it is preferable to wrap sealing tape or the like around the periphery of the part of the outflow pipe 16 that is fitted into the opening 124.

[0023] The reflector 17 is provided, for example, by placing a sheet made of fluororesin along the inner surface of the second portion 12, or by applying paint made of fluororesin to the inner surface of the second portion 12. To prevent ultraviolet light from leaking from the gap between the reflector 17 and the first portion 11, it is preferable that the reflector 17 be in contact with the end of the first portion 11 without any gaps. The reflector 17 may be in close contact with the inner surface of the second portion 12, or there may be a gap between the reflector 17 and the inner surface of the second portion 12.

[0024] When the reflecting material 17 is a sheet made of fluororesin, it has holes 171 through which the fluid passes. There may be one hole 171 or a collection of multiple holes. In order to prevent a decrease in the flow rate of the fluid in the flow path pipe 10 and an increase in pressure in the flow path pipe 10, it is preferable that the area of ​​the hole 171 (or the total area of ​​the holes if there is a collection of multiple holes) is larger than the areas of the inlet 102 and the outlet 103.

[0025] The fluororesin that is the material of the reflector 17 can be the same as the material of the first portion 11, and can be a fluororesin that reflects the light emitted from the ultraviolet light irradiation module 14. In particular, by using PTFE as the material of the reflector 17, sterilization can be effectively performed using the ultraviolet light irradiation module 14 that emits UVC light.

[0026] Furthermore, because the reflector 17 blocks much of the ultraviolet light directed toward the second portion 12, it is possible to suppress deterioration of the second portion 12 due to exposure to ultraviolet light. This means that the second portion 12 does not need to be resistant to ultraviolet light, which broadens the range of materials that can be selected for the second portion 12. For example, polycarbonate can be used as the material for the second portion 12.

[0027] In order to efficiently irradiate the light emitted from the ultraviolet light irradiation module 14 into the flow path 101, it is preferable that the opening 122 for taking in the light emitted from the ultraviolet light irradiation module 14 in the second section 12 and the opening 123 for connecting to the first section 11 are opposed to each other, and in this case, the area in the second section 12 where the reflector 17 is to be placed will be cylindrical. For this reason, a rectangular sheet made of fluororesin can be rolled into a ring shape and placed along the inner surface of the second section 12, and used as the reflector 17.

[0028] In this case, it is preferable that the reflector 17 and the second portion 12 have a misalignment prevention structure that prevents misalignment of the reflector 17 relative to the second portion 12. For example, it is preferable that the reflector 17 has a notch (cutout) 172 for preventing misalignment. By fitting this notch 172 into a rib (protrusion) 125 provided on the inner surface of the second portion 12, it is possible to prevent misalignment of the reflector 17 relative to the second portion 12. Note that, since the rib 125 of the second portion 12 is not covered by the reflector 17, it is preferable that it be provided on the ultraviolet light irradiation module 14 side where it is less likely to be exposed to ultraviolet light.

[0029] Fig. 4(a) is a plan view of reflecting material 17 made of a rectangular sheet, and Fig. 4(b) is a perspective view of reflecting material 17 made of a rectangular sheet rolled into a ring. In the example shown in Figs. 4(a) and (b), hole 171 consists of a group of four holes.

[0030] Note that the light emitted from the ultraviolet light irradiation module 14 usually contains visible light in addition to ultraviolet light. For this reason, by using a material that transmits visible light, such as transparent polycarbonate, for the material of the second portion 12, the visible light that leaks from the holes 171 of the reflector 17 and transmits through the second portion 12 can be visually recognized, allowing the operation of the ultraviolet light irradiation module 14 to be confirmed.

[0031] The third portion 13 has a shape that covers the end of the first portion 11 on the third portion 13 side, and has an inlet 102 .

[0032] The third part 13 has an opening 131 for connecting to the first part 11, and the first part 11 and the third part 13 are connected by fitting one end of the first part 11 into the inside of the opening 131. Here, in order to prevent fluid from leaking from the interface between the first part 11 and the third part 13, it is preferable to use a sealing member such as an O-ring 202 at the overlapping part of the first part 11 and the third part 13.

[0033] 1 to 3, inflow pipe 15 is connected to opening 132 on the inflow port 102 side of third section 13. Inflow pipe 15 is fitted and fixed inside opening 132, and the opening of inflow pipe 15 on the opposite side to opening 132 functions as inflow port 102. In this case, to effectively prevent fluid from leaking from the interface between third section 13 and inflow pipe 15, it is preferable to wrap sealing tape or the like around the periphery of the portion of inflow pipe 15 that is fitted into opening 132.

[0034] The functions of the inlet 102 and the outlet 103 in the flow path pipe 10 may be reversed. That is, the fluid may flow into the flow path 101 from the outlet 103 of the second portion 12, and the fluid may flow out from the inlet 102 of the third portion 13.

[0035] When a fluid flows into the flow path 101 from the inlet 102 and flows out from the outlet 103, i.e., when the inlet 102 functions as an inlet and the outlet 103 functions as an outlet, it is preferable that the end of the first part 11 on the third part 13 side (the end opposite the end on the second part 12 side), i.e., the fluid inlet of the first part 11, is covered by a flat diffusion plate 18.

[0036] 5(a) and 5(b) are a plan view and a cross-sectional view of an example of the diffusion plate 18. The cross section of the diffusion plate 18 shown in Fig. 5(b) is a cross section taken along the cutting line BB shown in Fig. 5(a).

[0037] The diffusion plate 18 has holes 181 at a position away from the center thereof through which the fluid passes, and diffuses the fluid that has flowed in from the inlet 102. The holes 181 are not provided at the center of the diffusion plate 18, but are provided near the outer periphery of the diffusion plate 18 or at a position that is in contact with the outer periphery. Therefore, the fluid that has passed through the holes 181 flows near the inner wall of the first portion 11.

[0038] Generally, the flow rate of a fluid flowing through a flow path decreases due to frictional resistance closer to the inner wall of the flow path, and the difference with the flow rate at the center of the flow path increases, but by using the diffuser plate 18 to cause the fluid to flow near the inner wall of the first portion 11, the flow rate near the inner wall of the first portion 11 can be relatively increased, thereby reducing the difference in flow rate between near the center and near the inner wall of the first portion 11. This averages out the residence time of the fluid in the flow path 101, thereby reducing the variation in the irradiation time of ultraviolet light due to differences in the fluid flow path, and enabling efficient sterilization.

[0039] In order to make the fluid flow as evenly as possible near the inner wall of the first portion 11, it is preferable that the plurality of holes 181 are arranged at equal intervals along the circumferential direction of the diffusion plate 18. In addition, in order to suppress a decrease in the flow rate of the fluid in the flow path pipe 10 and an increase in pressure in the flow path pipe 10, it is preferable that the area of ​​the hole 181 (the total area of ​​the holes 181 when a plurality of holes 181 is provided) is larger than the areas of the inlet 102 and the outlet 103.

[0040] To improve sterilization efficiency, the diffusion plate 18 is preferably made of a fluororesin that reflects the light emitted from the ultraviolet light irradiation module 14, similar to the material of the first portion 11. In particular, by using PTFE as the material for the diffusion plate 18, sterilization can be effectively performed using the ultraviolet light irradiation module 14 that emits UVC light.

[0041] Furthermore, when the diffuser 18 is used, the diffuser 18 blocks much of the ultraviolet light directed toward the third portion 13, thereby suppressing deterioration of the third portion 13 due to exposure to ultraviolet light. This eliminates the need for the third portion 13 to be resistant to ultraviolet light, which broadens the range of materials that can be selected for the third portion 13. In this case, for example, polycarbonate can be used as the material for the third portion 13.

[0042] There are no particular limitations on the method for fixing the diffusion plate 18 to the fluid sterilization device 1. For example, as shown in Figure 3, the diffusion plate 18 can be fixed by being sandwiched between the first part 11 and the third part 13. Here, the part outside the dotted line in Figure 5(a) is the part sandwiched between the first part 11 and the third part 13.

[0043] 6(a) and 6(b) are a plan view and a cross-sectional view of another example of the diffusion plate 18. The cross section of the diffusion plate 18 shown in Fig. 6(b) is a cross section taken along the cutting line CC shown in Fig. 6(a).

[0044] As shown in FIGS. 6(a) and 6(b), the holes 181 of the diffusion plate 18 may have an inclination such that they widen outward from the third portion 13 side toward the first portion 11 side.

[0045] It is also possible to use a diffusion member having a three-dimensional shape instead of the flat diffusion plate 18, but the flat shape is structurally simpler, and therefore manufacturing costs can be reduced when using expensive fluororesin, especially PTFE, which must be cut from a block.

[0046] Case 19 has a plate-like portion 191 parallel to the length of first portion 11 and a plate-like portion 192 that covers third portion 13, and by fixing case 19 to second portion 12 with plate-like portion 192 pressing third portion 13 toward first portion 11, first portion 11, second portion 12, and third portion 13 can be fixed together. In other words, case 19 can be used to fix the three parts, first portion 11, second portion 12, and third portion 13.

[0047] 1 to 3, case 19 has a plate-like portion 193 along the surface of second portion 12 facing the case 19, and case 19 is fixed to second portion 12 by screwing plate-like portion 193 to second portion 12 using screws 194. Case 19 is made of, for example, stainless steel.

[0048] As described above, the ultraviolet light irradiation module 14 is attached to the second section 12 and irradiates ultraviolet light onto the fluid flowing through the flow path 101. The ultraviolet light emitted by the ultraviolet light irradiation module 14 is, for example, ultraviolet light in a wavelength range called UV-A (400 to 315 nm), ultraviolet light in a wavelength range called UV-B (315 to 280 nm), or the above-mentioned UVC light, and among these, UVC light is preferred as it has the highest sterilizing effect.

[0049] 1 to 3, the ultraviolet light irradiation module 14 includes a light emitting element 141 that emits ultraviolet light, a wiring board 142 on which the light emitting element 141 is mounted, a cable 143 connected to the wiring of the wiring board 142 and used to supply power and the like from the outside to the light emitting element 141, a reflector 144 that surrounds the light emitting element 141, a waterproof sheet 145 placed on the reflector 144 so as to cover the upper part of the light emitting element 141, a heat sink 146 placed on the back side of the wiring board 142, and a cover 147 that covers and fixes these components. The area where the light emitting element 141 is mounted is sealed to ensure waterproofing, and light emitted from the light emitting element 141 is extracted through the waterproof sheet 145.

[0050] The light emitting element 141 includes, for example, an LED chip (Light Emitting Diode) or an LD chip (Laser Diode) that emits ultraviolet light, and a lens for adjusting the light distribution.

[0051] A sealing member such as an O-ring 203 is used between the mounting portion 121 of the second part 12 and the cover 147 of the ultraviolet light irradiation module 14 to prevent fluid from leaking from the interface between the second part 12 and the ultraviolet light irradiation module 14.

[0052] (Effects of the embodiment) According to the fluid sterilization device 1 of the above embodiment, a pipe made of a general-purpose fluororesin can be used for the first section 11 of the flow path pipe 10, and a reflective material 17 made of fluororesin is used for the second section 12, thereby increasing the reflectivity of ultraviolet light on the inner wall of the flow path 101 and ensuring excellent sterilization efficiency while reducing manufacturing costs. In particular, when PTFE is used as the fluororesin, cutting from a PTFE block is not required, which further increases the effect of reducing manufacturing costs.

[0053] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and various modifications can be made without departing from the spirit and scope of the invention. Furthermore, the components of the above-described embodiments can be combined in any manner without departing from the spirit and scope of the invention.

[0054] Furthermore, the above-described embodiments do not limit the scope of the invention as claimed, and it should be noted that not all of the combinations of features described in the embodiments are necessarily essential to the means for solving the problems of the invention. [Explanation of symbols]

[0055] 1 Fluid sterilizer 10 Flow pipe 101 Flow path 102 Inlet 103 Outlet 11 First Part 12 Second Part 121 Mounting part 13 Third Part 14 UV light irradiation module 15 Inflow pipe 16 Outflow pipe 17 Reflective material 171 hole 18 Diffuser 181 hole 19 cases

Claims

1. A flow path pipe having a flow path for flowing a fluid to be sterilized, an inlet for allowing the fluid to flow into the flow path, and an outlet for allowing the fluid to flow out of the flow path; an ultraviolet light irradiation module that irradiates ultraviolet light into the flow path; Equipped with the flow path pipe has a first portion having a circular cross section in a radial direction, and a second portion connected to one end of the first portion and having the outlet, the first portion is made of a fluororesin that reflects ultraviolet light emitted from the ultraviolet light irradiation module, the ultraviolet light irradiation module is attached to the second portion; a reflecting material made of fluororesin that reflects ultraviolet light emitted from the ultraviolet light irradiation module is provided along an inner surface of the second portion that becomes an inner wall of the flow path, a first hole through which the fluid passes, the first hole having an area larger than an area of ​​the outflow port, is formed at a position of the reflecting material corresponding to the outflow port, and a portion of the reflecting material other than the position where the first hole is formed is formed as a reflective surface; an end of the first portion opposite to the end of the second portion side is covered with a flat diffusion plate that diffuses the fluid that has flowed in from the inlet, the flat diffusion plate having a second hole at a position away from the center thereof through which the fluid passes in the flow direction of the flow path; the diffusion plate is made of a fluororesin that reflects the ultraviolet light emitted from the ultraviolet light irradiation module, and is formed as a reflective surface except for positions where the second holes are formed; The sterilization efficiency is improved by using the first portion, the reflecting material, and the diffusion plate to reflect the light. Fluid sterilizer.

2. The first hole of the reflector is a collection of one or more holes. The fluid disinfection device of claim 1 .

3. The second portion is formed of a material that transmits visible light, and whether or not the fluid has been sterilized can be confirmed based on the presence or absence of visible light contained in the ultraviolet light that has leaked through the hole and transmitted through the second portion. The fluid disinfection device of claim 1 .

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