Flowing water sterilization apparatus and flowing water sterilization method

Abstract

To prevent freezing of water to be treated during non-operation of a flowing water sterilization apparatus.SOLUTION: A flowing water sterilization apparatus 10 includes an inflow port 22, an outflow port 24, a housing 12 that accommodates water to be treated flowing from the inflow port 22 to the outflow port 24, a window member 32 facing the water to be treated, a light emitting element 26 that emits ultraviolet light 20 toward the water to be treated through the window member 32, a temperature sensor 28 that detects a temperature of the light emitting element 26, a heat transfer member 34 that transfers a heat generated when the light emitting element 26 is turned on to the water to be treated, and a control unit 16 which turns on the light emitting element 26 when the detection result of the temperature sensor 28 is a first temperature or below in the operating state where there is a flow of the water to be treated, and turns on the light emitting element 26 when the detection result of the temperature sensor 28 is a second temperature or below which is lower than the first temperature in the non-operating state where there is no flow of the water to be treated.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] There is a known running water sterilization device that sterilizes water to be treated by irradiating it with ultraviolet light. For example, a configuration is known in which ultraviolet light is irradiated to hot water output from a hot water supply device using a heat pump to sterilize it. The heat pump is operated in an anti-freeze mode according to the outside air temperature detected by a temperature detection unit (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0002] [Patent Document 1] JP 2020-151643 A Summary of the Invention [Problem to be solved by the invention]

[0003] In the above-mentioned prior art, the water to be treated needs to be heated or circulated to prevent freezing. Depending on the location of the running water sterilizer, it may be difficult to heat or circulate the water to be treated when the running water sterilizer is not in operation.

[0004] The present invention has been made in view of the above problems, and one of the exemplary objects thereof is to provide a technique for preventing freezing of the water to be treated when a running water sterilizer is not in operation. [Means for solving the problem]

[0005] A flowing water sterilization device according to one embodiment of the present invention comprises a housing having an inlet and an outlet and containing water to be treated flowing from the inlet to the outlet, a window member facing the water to be treated, a light-emitting element that irradiates ultraviolet light toward the water to be treated through the window member, a temperature sensor that detects the temperature of the light-emitting element, a heat transfer member that transfers heat generated when the light-emitting element is turned on to the water to be treated, and a control device that, in an operating state where there is a flow of water to be treated, turns on the light-emitting element when the detection result of the temperature sensor is equal to or lower than a first temperature, and that, in a non-operating state where there is no flow of water to be treated, turns on the light-emitting element when the detection result of the temperature sensor is equal to or lower than a second temperature lower than the first temperature.

[0006] Another aspect of the present invention is a method for sterilizing water by running water, which includes the steps of acquiring a signal indicating whether or not there is a flow of water to be treated from an inlet to an outlet, detecting the temperature of a light-emitting element that irradiates ultraviolet light through a window member toward the water to be treated, and turning on the light-emitting element when the detected temperature is equal to or lower than a first temperature in an operating state in which there is a flow of water to be treated, and turning on the light-emitting element when the detected temperature is equal to or lower than a second temperature that is lower than the first temperature in a non-operating state in which there is no flow of water to be treated. Effect of the Invention

[0007] According to the present invention, freezing of the water to be treated can be prevented when the running water sterilizer is not in operation. [Brief description of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view showing a schematic configuration of a running water sterilization device according to a first embodiment. [Diagram 2] 2 is a flowchart showing a running water sterilization method according to an embodiment. [Diagram 3] FIG. 11 is a cross-sectional view showing a schematic configuration of a running water sterilization device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. In the description, the same elements are given the same reference numerals, and duplicated descriptions will be omitted as appropriate. In order to facilitate understanding of the description, the dimensional ratios of the components in each drawing do not necessarily match the actual dimensional ratios.

[0010] (First embodiment) 1 is a diagram showing a schematic configuration of a running water sterilization device 10 according to a first embodiment. The running water sterilization device 10 includes a housing 12, a light source unit 14, and a control device 16. The running water sterilization device 10 irradiates the water to be treated flowing through a treatment flow path 18 inside the housing 12 with ultraviolet light 20 to perform a sterilization treatment.

[0011] The housing 12 defines a treatment flow path 18 through which the water to be treated flows. The housing 12 includes an inlet 22 and an outlet 24. The treatment flow path 18 is located between the inlet 22 and the outlet 24. The housing 12 is made of a resin material or a metal material. The housing 12 is made of a resin material such as polyethylene, polypropylene, or polytetrafluoroethylene, for example.

[0012] The light source unit 14 is disposed inside the housing 12. The light source unit 14 is disposed, for example, in the processing flow path 18, and disposed closer to the inlet 22 than the outlet 24. The light source unit 14 is disposed, for example, such that it is oriented to irradiate the ultraviolet light 20 toward the outlet 24.

[0013] The light source unit 14 includes a light emitting element 26, a temperature sensor 28, a substrate 30, a window member 32, and a heat transfer member 34.

[0014] The light emitting element 26 is a semiconductor light emitting element using, for example, aluminum gallium nitride (AlGaN), and is, for example, an LED (Light Emitting Diode) that outputs the ultraviolet light 20. The wavelength of the ultraviolet light 20 is, for example, not less than 200 nm and not more than 320 nm, for example, not less than 240 nm and not more than 280 nm. The light emitting element 26 is mounted on a substrate 30. The light source unit 14 can include, for example, a plurality of light emitting elements 26 mounted on the substrate 30.

[0015] The temperature sensor 28 is mounted on the substrate 30 and detects the temperature. The temperature sensor 28 detects the temperature of the substrate 30, and thereby detects the temperature of the light-emitting element 26. The detection result of the temperature sensor 28 is transmitted to the control device 16.

[0016] The substrate 30 supports the light emitting element 26 and the temperature sensor 28. The substrate 30 is attached to a heat transfer member 34, and transfers heat generated when the light emitting element 26 is turned on to the heat transfer member 34. The substrate 30 is preferably made of a substrate material that has high thermal conductivity, for example, and is based on a metal material such as aluminum or copper. A highly thermally conductive material (not shown), such as thermal grease, may be disposed between the substrate 30 and the heat transfer member 34.

[0017] The window member 32 is disposed so as to face the water to be treated flowing through the treatment flow path 18. The window member 32 is made of a material that transmits ultraviolet light 20, such as quartz (SiO2), sapphire (Al2O3), or amorphous fluororesin. The window member 32 is provided, for example, so as to close an opening 36 provided in the heat transfer member 34, and is supported by the heat transfer member 34. The window member 32, together with the heat transfer member 34, defines a light source chamber 38 in a watertight manner. A sealing member (not shown), such as a seal ring, can be provided between the window member 32 and the heat transfer member 34.

[0018] The heat transfer member 34, together with the window member 32, defines a light source chamber 38. The heat transfer member 34 has an opening 36 that allows the ultraviolet light 20 from the light-emitting element 26 to pass through. The light-emitting element 26, the temperature sensor 28, and the substrate 30 are disposed in the light source chamber 38. The heat transfer member 34 transfers heat generated when the light-emitting element 26 is turned on to the water to be treated inside the housing 12. The heat transfer member 34 is made of a metal material such as stainless steel, copper, or aluminum.

[0019] The running water sterilization device 10 may further include a flow sensor 40. The flow sensor 40 detects the presence or absence of a flow of the water to be treated from the inlet 22 toward the outlet 24, and outputs a flow signal indicating whether or not there is a flow. The flow sensor 40 may be provided, for example, at the outlet 24. There is no particular limit to the location where the flow sensor 40 is installed, and it may be provided at the inlet 22 or in the treatment flow path 18.

[0020] The control device 16 controls the lighting of the light-emitting element 26. The control device 16 acquires the detection result of the temperature sensor 28. The control device 16 acquires a flow signal indicating whether or not there is a flow of the water to be treated from the inlet 22 toward the outlet 24. The control device 16 acquires the flow signal from, for example, a flow sensor 40 provided inside the housing 12. The control device 16 may acquire the flow signal from a device (not shown) provided upstream or downstream of the flowing water sterilization device 10.

[0021] The control device 16 is disposed outside the housing 12 and is connected to the board 30 via a cable 42. The control device 16 may be disposed inside the housing 12, for example, in the light source chamber 38.

[0022] The control device 16 includes an integrated circuit such as an MCU (Micro Controller Unit). In terms of hardware, the control device 16 can be realized by elements and mechanical devices such as a computer CPU and memory, and in terms of software, the control device 16 can be realized by a computer program, etc. Those skilled in the art will understand that the control device 16 can be realized in various forms by combining hardware and software.

[0023] When the control device 16 is in an operating state with a flow of water to be treated, it turns on the light-emitting element 26 with a predetermined drive current and sterilizes the water to be treated flowing through the treatment flow path 18 with ultraviolet light 20. When the detection result of the temperature sensor 28 is equal to or lower than a first temperature in the operating state, the control device 16 turns on the light-emitting element 26. When the detection result of the temperature sensor 28 exceeds the first temperature in the operating state, the control device 16 turns off the light-emitting element 26. The first temperature corresponds to the allowable upper limit temperature at which the light-emitting element 26 can operate, and is, for example, 50°C or higher and 100°C or lower. When the first temperature is exceeded, the control device 16 turns off the light-emitting element 26 to prevent an excessive temperature rise in the light-emitting element 26.

[0024] When the control device 16 is in a non-operating state where there is no flow of water to be treated, the control device 16 turns on the light-emitting element 26 to prevent the water to be treated from freezing. When the detection result of the temperature sensor 28 in the non-operating state is equal to or lower than a second temperature lower than the first temperature, the control device 16 turns on the light-emitting element 26. When the detection result of the temperature sensor 28 in the non-operating state exceeds the second temperature, the control device 16 turns off the light-emitting element 26. The second temperature corresponds to a first reference temperature at which it is considered necessary to prevent the water to be treated from freezing, and is, for example, 5°C or higher and 10°C or lower.

[0025] When the control device 16 is in a non-operating state, the control device 16 may start turning on the light-emitting element 26 when the detection result of the temperature sensor 28 becomes equal to or lower than a third temperature lower than the second temperature. The third temperature corresponds to a second reference temperature at which the treated water is likely to freeze, and is, for example, 1°C or higher and 5°C or lower. When the control device 16 is in a non-operating state, the control device 16 may not turn on the light-emitting element 26 when the temperature is decreasing from the second temperature to the third temperature, and may turn on the light-emitting element 26 when the temperature is increasing from the third temperature to the second temperature. The control device 16 may, for example, intermittently turn on the light-emitting element 26 so that the detection result of the temperature sensor 28 is maintained equal to or higher than the third temperature and equal to or lower than the second temperature.

[0026] Next, the operation of the flowing water sterilization device 10 will be described. Water to be treated that is the target of sterilization treatment flows into the housing 12 from the inlet 22, passes through the treatment flow path 18, and flows out from the outlet 24. The light source unit 14 irradiates the water to be treated flowing through the treatment flow path 18 with ultraviolet light 20. Heat generated when the light-emitting element 26 is turned on is transferred to the water to be treated via the substrate 30 and the heat transfer member 34. In an operating state where there is a flow of the water to be treated, the light-emitting element 26 is cooled to a first temperature or lower by the flow of the water to be treated.

[0027] In a non-operating state where there is no flow of the water to be treated, the light-emitting element 26 is turned off in principle. When it is necessary to prevent the water to be treated from freezing in a non-operating state, the light-emitting element 26 is turned on, and the heat generated when the light-emitting element 26 is turned on is used to heat the water to be treated. When the water to be treated is heated to a degree that there is no risk of the water freezing, the light-emitting element 26 is turned off. Specifically, when the water is below the second temperature or below the third temperature in a non-operating state, the light-emitting element 26 is turned on, and when the water exceeds the second temperature in a non-operating state, the light-emitting element 26 is turned off. In this way, the water to be treated in a non-operating state is heated to a temperature between the third temperature and the second temperature, and the water to be treated can be prevented from freezing. By preventing the water to be treated from freezing, damage to the window member 32 and the like caused by the expansion of the water to be treated due to freezing can be prevented.

[0028] 2 is a flow chart showing a flowing water sterilization method according to an embodiment. The control device 16 acquires a flow signal indicating whether or not there is a flow of the water to be treated from the flow sensor 40 (S10), and acquires a temperature detection result from the temperature sensor 28 (S12). When the control device 16 is in an operating state with a flow (Y of S14) and the temperature detection result is equal to or lower than the first temperature (Y of S16), it turns on the light-emitting element 26 (S18) and sterilizes the water to be treated with the ultraviolet light 20. When the control device 16 is in an operating state with a flow (Y of S14) and the detection result exceeds the first temperature (N of S16), it turns off the light-emitting element 26 (S20) to protect the light-emitting element 26 from heat.

[0029] If the control device 16 is in a non-operating state with no flow (N in S14), and the temperature detection result is equal to or lower than the second temperature (Y in S22), and if the light-emitting element 26 is on (Y in S24), the control device 16 continues to turn on the light-emitting element 26 (S18) and heats the water to be treated using the heat generated when the light-emitting element 26 is on. If the light-emitting element 26 is off (N in S24) and the temperature detection result is equal to or lower than the third temperature (Y in S26), the control device 16 turns on the light-emitting element 26 (S18) and heats the water to be treated using the heat generated when the light-emitting element 26 is on. If the temperature detection result exceeds the second temperature (N in S22) or exceeds the third temperature (N in S26), the control device 16 turns off the light-emitting element 26 (S28).

[0030] According to this embodiment, by turning on the light-emitting element 26 when the running water sterilization device 10 is not in operation, the heat generated when the light-emitting element 26 is turned on can be used to heat the water to be treated inside the housing 12, thereby preventing the water from freezing. By using the light source unit 14 disposed inside the housing 12 as a heat source, the water to be treated inside the housing 12 can be effectively heated without using an additional heater or the like.

[0031] According to this embodiment, by providing a heat transfer member 34 that transfers heat generated when the light-emitting element 26 is turned on, the light-emitting element 26 in the operating state can be cooled by the flow of the water to be treated, and the water to be treated in the non-operating state can be heated by the driving heat of the light-emitting element 26. This makes it possible to effectively suppress the temperature rise of the light-emitting element 26 in the operating state, while effectively suppressing the freezing of the water to be treated in the non-operating state.

[0032] (Second embodiment) 3 is a diagram showing a schematic configuration of a running water sterilizer 10A according to a second embodiment. The running water sterilizer 10A differs from the above-mentioned first embodiment in that it further includes a partition member 50 disposed inside the housing 12. The second embodiment will be described below, focusing on the differences from the first embodiment, and a description of the commonalities will be omitted as appropriate.

[0033] The running water sterilization device 10A includes a housing 12, a light source unit 14, a control device 16, and a partition member 50. The running water sterilization device 10A may further include a flow sensor 40. The housing 12, the light source unit 14, the control device 16, and the flow sensor 40 may be configured in the same manner as in the first embodiment.

[0034] The partition member 50 is disposed between the light source unit 14 and the outlet 24. The partition member 50 has an open end 52 facing the light source unit 14 or the window member 32. The partition member 50 extends from the open end 52 toward the outlet 24 to define the treatment flow path 18A. A gap 54 through which the water to be treated passes is formed between the light source unit 14 or the window member 32 and the open end 52. The water to be treated flowing in from the inlet 22 passes through the gap 54 and flows into the treatment flow path 18A, and toward the outlet 24.

[0035] The partition member 50 is made of a material having a high reflectance of the ultraviolet light 20, for example, a fluororesin such as polytetrafluoroethylene. By providing the partition member 50, the ultraviolet light 20 is reflected inside the treatment flow path 18A, and the amount of the ultraviolet light 20 acting on the water to be treated can be improved. By providing the partition member 50, the water to be treated can be guided to the center of the treatment flow path 18A where the amount of irradiation of the ultraviolet light 20 is relatively large. This improves the sterilization performance of the running water sterilization device 10.

[0036] In this embodiment, since a double structure is formed in which the partition member 50 is provided inside the housing 12, it is difficult to heat the water to be treated located inside the partition member 50 from outside the housing 12. According to this embodiment, the water to be treated inside the partition member 50 can be heated using the light source unit 14, so that the water to be treated in the treatment flow path 18A can be effectively prevented from freezing.

[0037] The present invention has been described above based on the embodiments. It will be understood by those skilled in the art that the present invention is not limited to the above-described embodiments, that various design changes are possible, that various modifications are possible, and that such modifications are also within the scope of the present invention.

[0038] Several aspects of the present invention will now be described.

[0039] A first aspect of the present invention is a flowing water sterilization device including a housing having an inlet and an outlet and containing water to be treated flowing from the inlet to the outlet, a window member facing the water to be treated, a light-emitting element irradiating ultraviolet light through the window member toward the water to be treated, a temperature sensor detecting the temperature of the light-emitting element, a heat transfer member transferring heat generated when the light-emitting element is turned on to the water to be treated, and a control device that turns on the light-emitting element when the temperature sensor detects a first temperature or lower in an operating state where the water to be treated is flowing, and turns on the light-emitting element when the temperature sensor detects a second temperature or lower that is lower than the first temperature in a non-operating state where the water to be treated is not flowing. According to the first aspect, by turning on the light-emitting element when the temperature is the second temperature or lower in the non-operating state, the water to be treated can be heated using the heat generated when the light-emitting element is turned on, and the water to be treated can be prevented from freezing.

[0040] A second aspect of the present invention is the running water sterilization device according to the first aspect, in which the control device starts turning on the light-emitting element when the detection result of the temperature sensor becomes equal to or lower than a third temperature lower than the second temperature in the non-operating state, and turns off the light-emitting element when the detection result of the temperature sensor exceeds the second temperature. According to the second aspect, by starting to turn on the light-emitting element when the temperature is equal to or lower than the third temperature in the non-operating state, the light-emitting element can be turned on only when the temperature is low and there is a high possibility of freezing the water to be treated. This reduces the amount of power consumption and extends the life of the light-emitting element. In addition, by turning on the light-emitting element throughout the process of the temperature rise from the third temperature to the second temperature, the water to be treated can be efficiently heated in a situation where there is a high possibility of freezing the water to be treated.

[0041] A third aspect of the present invention is the running water sterilization device according to the first or second aspect, wherein the control device intermittently lights up the light-emitting element when the detection result of the temperature sensor is equal to or lower than the second temperature in the non-operating state. According to the third aspect, by intermittently lighting up the light-emitting element when the temperature is equal to or lower than the second temperature in the non-operating state, it is possible to reduce power consumption and extend the life of the light-emitting element.

[0042] A fourth aspect of the present invention is the running water sterilization apparatus according to any one of the first to third aspects, further comprising a flow sensor for detecting the flow of the water to be treated. According to the fourth aspect, by using the flow sensor, it is possible to appropriately detect whether the apparatus is in an operating state or a non-operating state, and it is possible to appropriately prevent the water to be treated from freezing in a non-operating state.

[0043] A fifth aspect of the present invention is the running water sterilization apparatus according to any one of the first to fourth aspects, in which the window member is supported by the heat transfer member. According to the fifth aspect, heat generated when the light-emitting element is turned on can also be transferred to the window member, so that the light-emitting element can be cooled via the window member and the water to be treated can be heated via the window member. This improves the cooling efficiency of the light-emitting element and more effectively prevents the water to be treated from freezing. In particular, the water to be treated near the window member can be heated, so that damage to the window member due to freezing of the water to be treated can be effectively prevented.

[0044] A sixth aspect of the present invention is the running water sterilization device according to any one of the first to fifth aspects, wherein the heat transfer member defines a light source chamber that houses the light emitting element and the temperature sensor and is disposed inside the housing. According to the sixth aspect, since the heat transfer member is disposed inside the housing, the cooling efficiency of the light emitting element can be improved and the freezing of the water to be treated can be more effectively prevented.

[0045] A seventh aspect of the present invention is the running water sterilization device according to any one of the first to sixth aspects, further comprising a partition member disposed inside the housing, having an open end facing the window member, and defining a treatment flow path from the open end toward the outlet. According to the seventh aspect, by providing the partition member inside the housing, the water to be treated can be guided to a region where the ultraviolet light is irradiated through the window member, and the amount of action of the ultraviolet light on the water to be treated can be improved.

[0046] An eighth aspect of the present invention is a method for sterilizing water, comprising the steps of: acquiring a flow signal indicating whether or not there is a flow of water to be treated from an inlet toward an outlet; detecting the temperature of a light-emitting element that irradiates ultraviolet light through a window member toward the water to be treated; and turning on the light-emitting element when the temperature detection result is equal to or lower than a first temperature in an operating state in which the water to be treated is flowing, and turning on the light-emitting element when the temperature detection result is equal to or lower than a second temperature lower than the first temperature in a non-operating state in which the water to be treated is not flowing. According to the eighth aspect, by turning on the light-emitting element when the temperature is equal to or lower than the second temperature in the non-operating state, the water to be treated can be heated using heat generated when the light-emitting element is turned on, and freezing of the water to be treated can be prevented. [Explanation of symbols]

[0047] 10, 10A... running water sterilization device, 12... housing, 14... light source unit, 16... control device, 18, 18A... treatment flow path, 20... ultraviolet light, 22... inlet, 24... outlet, 26... light-emitting element, 28... temperature sensor, 32... window member, 34... heat transfer member, 36... opening, 38... light source chamber, 40... flow sensor, 50... partition member, 52... opening end.

Claims

1. A housing having an inlet and an outlet, the housing containing water to be treated flowing from the inlet to the outlet; A window member facing the water to be treated; A light emitting element that irradiates ultraviolet light toward the water to be treated through the window member; A temperature sensor for detecting a temperature of the light-emitting element; A heat transfer member that transfers heat generated when the light-emitting element is turned on to the water to be treated; a control device that, in an operating state in which there is a flow of the water to be treated, turns on the light-emitting element when the detection result of the temperature sensor is equal to or lower than a first temperature, and, in a non-operating state in which there is no flow of the water to be treated, turns on the light-emitting element when the detection result of the temperature sensor is equal to or lower than a second temperature lower than the first temperature; A running water sterilization device.

2. The control device, in the non-operating state, starts turning on the light-emitting element when the detection result of the temperature sensor becomes equal to or lower than a third temperature that is lower than the second temperature, and turns off the light-emitting element when the detection result of the temperature sensor exceeds the second temperature. The running water sterilizer according to claim 1.

3. the control device intermittently lights up the light-emitting element when a detection result of the temperature sensor is equal to or lower than the second temperature in the non-operating state. The running water sterilizer according to claim 1.

4. Further comprising a flow sensor for detecting the flow of the water to be treated. The running water sterilizer according to any one of claims 1 to 3.

5. The window member is supported by the heat transfer member. The running water sterilizer according to any one of claims 1 to 3.

6. the heat transfer member defines a light source chamber that houses the light emitting element and the temperature sensor, and is disposed inside the housing; The running water sterilizer according to any one of claims 1 to 3.

7. a partition member disposed inside the housing, the partition member having an open end facing the window member and defining a processing flow path from the open end toward the outlet; The running water sterilizer according to any one of claims 1 to 3.

8. obtaining a flow signal indicating whether there is a flow of water to be treated from the inlet to the outlet; detecting a temperature of a light-emitting element that irradiates ultraviolet light through a window member toward the water to be treated; a step of turning on the light-emitting element when the temperature detection result is equal to or lower than a first temperature in an operating state where there is a flow of the water to be treated, and turning on the light-emitting element when the temperature detection result is equal to or lower than a second temperature lower than the first temperature in a non-operating state where there is no flow of the water to be treated; A method for sterilizing with running water.

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