Hypochlorous acid water generator, air disinfection device, and method for measuring hypochlorous acid concentration

Abstract

To measure a concentration of hypochlorous acid using electrodes used for electrolysis.SOLUTION: There is provided a hypochlorous acid water generator including: an electrolytic cell 210; an electrolyzer 230 that applies a DC voltage to a pair of electrodes 220 to electrolyze chlorine-containing water to generate hypochlorous acid water; measurement means 110 that measures conductivity information indicating a conductivity of the hypochlorous acid water; a measurement control device 120 that controls the measurement means 110; and switching means 140 that switches a connection between the electrode 220 and the electrolyzer 230 and a connection between the electrode 220 and the measurement means 110. The measurement means 110 includes an application measuring device 112 that applies an AC voltage between the pair of electrodes 220. The measurement control device 120 includes: a measurement information acquisition unit 121 that acquires the conductivity information from the measurement means 110; a conversion information acquisition unit 122 that acquires conversion information indicating a relation between hypochlorous acid concentration and the conductivity information; and a concentration calculation unit 123 that calculates the hypochlorous acid concentration based on the conductivity information and the conversion information.SELECTED DRAWING: Figure 1

Description

Technical Field

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[0005] , , ,

[0001] The present invention relates to a hypochlorous acid water generator, a space disinfection device, and a method for measuring the concentration of hypochlorous acid.

Background Art

[0002] Patent Document 1 describes a so-called polarographic measurement technique for measuring the concentration of hypochlorous acid water based on the electrochemical reduction current of hypochlorous acid.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] ​​​​​​​​

[0006] To achieve the above objective, a hypochlorous acid water generator according to one aspect of the present invention comprises: an electrolytic cell for storing water containing chlorine; a pair of electrodes arranged in an inserted state in the electrolytic cell; an electrolytic device for applying a DC voltage to the pair of electrodes and electrolyzing the water containing chlorine to generate hypochlorous acid water; a measuring means for measuring conductivity information indicating the conductivity of the hypochlorous acid water stored in the electrolytic cell; a measuring control device for controlling the measuring means; and a switching means for switching between the connection between the pair of electrodes and the electrolytic device and the connection between the pair of electrodes and the measuring means, wherein the measuring means comprises an application measuring device for applying an AC voltage between the pair of electrodes; and the measuring control device comprises a measuring information acquisition unit for acquiring conductivity information from the measuring means; a conversion information acquisition unit for acquiring conversion information indicating the relationship between hypochlorous acid concentration and the conductivity information; and a concentration calculation unit for calculating hypochlorous acid concentration based on the measured conductivity information and the conversion information.

[0007] Furthermore, a space sterilization device according to one aspect of the present invention comprises: an electrolytic cell for storing water containing chlorine; a pair of electrodes arranged in an inserted state in the electrolytic cell; an electrolytic device for applying a DC voltage to the pair of electrodes and electrolyzing the water containing chlorine to generate hypochlorous acid water; a measuring means for measuring conductivity information indicating the conductivity of the hypochlorous acid water stored in the electrolytic cell; a measuring control device for controlling the measuring means; a switching means for switching between the connection between the pair of electrodes and the electrolytic device and the connection between the pair of electrodes and the measuring means; and a diffusion means for diffusing the generated hypochlorous acid water into the atmosphere. The measuring means comprises an application measuring device for applying an AC voltage between the pair of electrodes, and the measuring control device comprises a measuring information acquisition unit for acquiring conductivity information from the measuring means; a conversion information acquisition unit for acquiring conversion information indicating the relationship between hypochlorous acid concentration and the conductivity information; and a concentration calculation unit for calculating hypochlorous acid concentration based on the measured conductivity information and the conversion information.

[0008] Furthermore, a hypochlorous acid concentration measurement method according to one aspect of the present invention is a hypochlorous acid concentration measurement method for measuring the concentration of hypochlorous acid generated by electrolyzing chlorine-containing water stored in an electrolytic cell using a pair of electrodes to which a voltage is applied, wherein when electrolysis is not being performed, a measurement instruction unit uses a switching means to switch the connection between the electrodes and the measurement means to cause the measurement means to perform conductivity information measurement, a measurement information acquisition unit acquires conductivity information from the measurement means that has measured conductivity information indicating the conductivity of the hypochlorous acid water stored in the electrolytic cell, a conversion information acquisition unit acquires conversion information indicating the relationship between the hypochlorous acid concentration and the conductivity information, and a concentration calculation unit calculates the hypochlorous acid concentration based on the acquired conductivity information and the conversion information.

[0009] The above hypochlorous acid concentration measurement method can be implemented as a program for a computer to execute. Alternatively, it can be implemented as a computer-readable recording medium containing the program. [Effects of the Invention]

[0010] According to the present invention, the hypochlorous acid concentration of the generated hypochlorous acid water can be measured with a simple apparatus configuration. [Brief explanation of the drawing]

[0011] [Figure 1] This is a simplified side view of the space sterilization device according to this embodiment. [Figure 2] This is a block diagram showing the functional configuration of a measurement and control device. [Figure 3] This graph shows the relationship between hypochlorous acid concentration and the conductivity of hypochlorous acid water. [Figure 4] This graph shows the relationship between the cumulative difference in conductivity and the hypochlorous acid concentration. [Figure 5] This is a block diagram of the circuit for measuring liquid resistance values ​​provided by the measuring device. [Figure 6] This is a flowchart showing the operation flow of a space disinfection device. [Figure 7] This figure shows another example of a switching mechanism. [Modes for carrying out the invention]

[0012] The embodiments of the hypochlorous acid water generator, space disinfection device, and hypochlorous acid concentration measurement method according to the present invention will be described below with reference to the drawings. The following embodiments are provided as examples to illustrate the present invention and are not intended to limit it. For example, the shapes, structures, materials, components, relative positional relationships, connection states, numerical values, mathematical formulas, the content of each step in the method, and the order of each step shown in the following embodiments are examples and may include content not described below. Geometric expressions such as parallel and orthogonal may be used, but these expressions do not indicate mathematical rigor and include substantially acceptable errors and deviations. Similarly, expressions such as simultaneous and identical also include substantially acceptable ranges.

[0013] Furthermore, the drawings are schematic diagrams that have been appropriately emphasized, omitted, or had their proportions adjusted to illustrate the present invention, and therefore differ from the actual shape, positional relationships, and proportions. Also, the X, Y, and Z axes shown in the drawings represent orthogonal coordinates arbitrarily set for the purpose of explaining the drawings. In other words, the Z axis is not necessarily an axis along the vertical direction, and the X and Y axes are not necessarily located in the horizontal plane.

[0014] Furthermore, in the following, multiple inventions may be comprehensively described as a single embodiment. Also, some of the content described below is described as an optional component relating to the present invention.

[0015] Furthermore, the flowchart is merely an example, and embodiments of the present invention are included even if the order of processing differs, multiple processes are integrated, or a single process is separated.

[0016] FIG. 1 is a diagram simply showing the space sterilization device 200 according to the present embodiment from the side. The space sterilization device 200 releases hypochlorous acid water into the space. Further, the space sterilization device 200 introduces the air in the space into the hypochlorous acid water. The space targets a closed space such as an indoor space of a building. Specifically, examples of the space can include a living space in a general household, or an indoor space in a hospital or a nursing facility. Note that the space does not have to be a completely closed space and may be connected to the outdoors. Also, the space may be not only a space within a building but also a space within a moving body such as a train or an automobile.

[0017] Hypochlorous acid water has a sterilization and deodorizing effect. Specifically, hypochlorous acid water has an oxidizing action and performs sterilization and deodorization by decomposing floating bacteria in the space, adherent bacteria attached to an object, or odor substances by oxidation. Note that the term "sterilization" is described for convenience in this specification and the claims and includes meanings such as "disinfection". Also, "bacteria" is described as including viruses, molds, and the like.

[0018] As shown in FIG. 1, the space sterilization device 200 includes a hypochlorous acid water generator 100 and a diffusion means 240. The hypochlorous acid water generator 100 includes an electrolytic cell 210, a pair of electrodes 220, an electrolysis device 230, a measurement means 110, a main control device 250, and a switching means 140.

[0019] The electrolytic cell 210 is a water tank that stores water containing chlorine, and hypochlorous acid water is generated by electrolyzing the water containing chlorine in the electrolytic cell 210. Examples of the water containing chlorine can include water in which salt is dissolved.

[0020] The electrode 220 is a pair of conductive members arranged in an inserted state in the water containing chlorine stored in the electrolytic cell 210. The shape of the electrode 220 is not particularly limited, but in the case of the present embodiment, it is a rectangular plate shape (strip shape). The electrodes 220 are arranged such that their main surfaces (the surfaces with the largest area) face each other. The material of the electrode 220 is not particularly limited as long as it has conductivity. For example, as the electrode 220, a configuration in which a catalyst layer is coated on the surface of a conductive substrate can be cited. Examples of the conductive substrate include a single metal such as titanium, iron, copper, niobium, tantalum, or an alloy thereof. Considering the ease of processing during manufacturing or the manufacturing cost, the material of the conductive substrate is preferably titanium or a titanium alloy. Examples of the catalyst contained in the catalyst layer include a catalyst containing platinum, iridium, etc. As other mixtures contained in the catalyst layer, any metal state such as a metal, an alloy, a metal oxide, etc. may be used. Examples include lead, gold, nickel, copper, silver, iron, palladium, ruthenium, rhodium, carbon, etc.

[0021] The electrolysis device 230 is a DC power supply device that applies a predetermined DC voltage between the pair of electrodes 220. The electrolysis device 230 selects whether to apply a voltage to the pair of electrodes 220, that is, on or off of the voltage application to the pair of electrodes in accordance with the control of the main control device 250.

[0022] The diffusion means 240 is a cylindrical member that rotates around the tube axis (the left - right direction in FIG. 1). A part of the periphery of the diffusion means 240 is periodically immersed in the hypochlorous acid water stored in the electrolytic cell 210, and water is lifted above the liquid level of the hypochlorous acid water by utilizing capillary action or the like. By passing air through the hypochlorous acid water lifted above the liquid level, minute droplets of the hypochlorous acid water are diffused into the atmosphere. Bacteria (including viruses, molds, etc.) present in the atmosphere are sterilized (including inactivation of viruses, molds, etc.) by coming into contact with the hypochlorous acid water lifted by the diffusion means 240. Also, they are sterilized by coming into contact with the hypochlorous acid water diffused into the atmosphere.

[0023] The main control unit 250 is equipped with a processor and controls the air sterilization device 200 by having the processor execute a program. In this embodiment, the main control unit 250 obtains the hypochlorous acid concentration in the electrolytic cell 210 from the hypochlorous acid water generator 100 (described later) and controls the electrolytic device 230 so that the hypochlorous acid concentration remains constant. Here, hypochlorous acid concentration refers to the total concentration of hypochlorous acid and hypochlorite ions. The main control unit 250 also obtains water level information from the water level sensor 260 provided in the electrolytic cell 210, and controls the electrolytic device 230 so that it does not operate if the water level in the electrolytic cell 210 has not reached a predetermined water level threshold.

[0024] The switching means 140 switches between the connection between the pair of electrodes 220 and the electrolytic device 230 and the connection between the pair of electrodes 220 and the measuring means 110. In this embodiment, the switching means 140 employs a relay that exclusively switches between the connection between the pair of electrodes 220 and the electrolytic device 230 and the connection between the pair of electrodes 220 and the measuring means 110 using mechanical contacts. This prevents the current generated when generating hypochlorous acid water from flowing into the measuring means 110 and causing malfunctions in the measuring means 110. Furthermore, when measuring the concentration of hypochlorous acid, the influence of the electrolytic device 230 can be eliminated, allowing for accurate measurement.

[0025] The hypochlorous acid water generator 100 is a device that measures the concentration of hypochlorous acid generated by electrolyzing chlorine-containing water stored in an electrolytic cell 210 using an electrode 220 used for electrolysis, and comprises a measuring means 110 and a measuring control device 120.

[0026] The measuring means 110 is a device for measuring conductivity information indicating the conductivity of hypochlorous acid water stored in the electrolytic cell 210, and is connectable to the electrode 220 via a switching means 140 and includes an applied measuring device 112. In this embodiment, the measuring means 110 includes a water temperature sensor 113 for measuring temperature information indicating the temperature of the water stored in the electrolytic cell 210.

[0027] The applied voltage measurement device 112 includes an AC power supply device 131 (see Figure 5) that applies a predetermined AC voltage between a pair of electrodes 220 connected via a switching means 140. The applied voltage measurement device 112 also includes a liquid resistance value measuring device 132 (see Figure 5) that measures the liquid resistance value between the pair of electrodes 220 as conductivity information. The applied voltage measurement device 112 selects whether or not to apply an AC voltage to the electrodes 220, that is, whether to turn the application of the AC voltage to the pair of electrodes 220 on or off, under the control of the measurement control device 120. Preferably, the frequency of the AC voltage applied by the applied voltage measurement device 112 between the pair of electrodes 220 is selected from a range of 1 kHz or more and 100 kHz or less. By applying an AC voltage in this relatively high frequency range, the liquid resistance value measuring device 132 can measure the liquid resistance value without imaginary terms when calculating the liquid resistance value of hypochlorous acid water using the AC impedance method. In other words, the inventors have found that by using the AC impedance method at the above-mentioned frequency range, the degree of deterioration of the electrode 220 used to generate hypochlorous acid water can be ignored, and the liquid resistance value can be measured stably. Although the example given is that the applied measurement device 112 includes an AC power supply device 131 that applies an AC voltage, the applied measurement device 112 may also include an AC power supply device 131 that applies an AC current. In this case, the measurement control device 120 may also control the AC current.

[0028] Figure 2 is a block diagram showing the functional configuration of the measurement control device 120. The measurement control device 120 includes a processor, which executes a program to control the timing at which the applied measuring device 112 applies an AC voltage to the electrodes 220 connected via a pair of switching means 140. It also acquires conductivity information indicating the conductivity of the hypochlorous acid water obtained by applying the AC voltage. The measurement control device 120 includes a measurement information acquisition unit 121, a conversion information acquisition unit 122, and a concentration calculation unit 123 as processing units. In this embodiment, the measurement control device 120 includes an electrolysis execution acquisition unit 125, a measurement instruction unit 124, a correction information acquisition unit 126, a measurement adjustment unit 127, and a cleaning unit 128.

[0029] The measurement information acquisition unit 121 acquires conductivity information from the measurement means 110. The conductivity information acquired from the measurement means 110 is not particularly limited and can be the conductivity (electrical conductivity) of hypochlorous acid water, or any information from which conductivity can be derived by calculation. For example, the conductivity information may be the liquid resistance value of hypochlorous acid water. Alternatively, the measurement information acquisition unit 121 may acquire the liquid resistance value measured by the measurement control device 120 using the AC impedance method, and derive the conductivity by calculating the reciprocal of the acquired liquid resistance value.

[0030] In this embodiment, the measurement information acquisition unit 121 also acquires temperature information from the water temperature sensor 113 provided by the measurement means 110.

[0031] The conversion information acquisition unit 122 acquires conversion information showing the relationship between hypochlorous acid concentration and conductivity information. The inventor stored chlorine-containing water (hereinafter referred to as water in this paragraph) in the electrolytic cell 210 and performed electrolysis of the water at a predetermined voltage for a predetermined time. When no electrolysis was performed at all (0 times), the hypochlorous acid concentration and the conductivity of the water were measured, and each time electrolysis of water was performed under the above conditions, the hypochlorous acid concentration and the conductivity of the water were measured. Based on the above experiment, the inventor found that the hypochlorous acid concentration and the conductivity of the water are inversely proportional, as shown in Figure 3. Note that m in Figure 3 is an integer. Also, the specific numerical values ​​of hypochlorous acid concentration and conductivity are omitted.

[0032] Based on the above, the inventor created a function as conversion information showing the relationship between hypochlorous acid concentration and conductivity, as shown in the graph of Figure 4. In this embodiment, the conversion information acquisition unit 122 acquires the function stored in the storage device 102 of the measurement control device 120 as conversion information. The vertical axis of the graph shown in Figure 4 represents the difference in conductivity. The difference in conductivity will be explained later.

[0033] The concentration calculation unit 123 calculates the hypochlorous acid concentration based on the conductivity information obtained from the measurement means 110 and the conversion information obtained from the conversion information acquisition unit 122. The concentration calculation unit 123 outputs the calculated hypochlorous acid concentration to the main control device 250. A detailed explanation of the concentration calculation unit 123 will be given later.

[0034] The electrolysis execution acquisition unit 125 acquires execution information from the main control unit 250 that indicates the execution status of electrolysis performed in the electrolytic device 230 and the electrodes 220. This allows the electrolysis execution acquisition unit 125 to determine from the execution information whether electrolysis is being performed or not within the electrolytic cell 210.

[0035] The measurement instruction unit 124 controls the measurement means 110 to measure conductivity information by switching the switching means 140 to connect the electrodes 220 and the measurement means 110 when electrolysis is not being performed, based on the execution information acquired by the electrolysis execution acquisition unit 125. In the normal state, the switching means 140 is maintained with the pair of electrodes 220 and the electrolytic device 230 connected, and switches to connect the electrodes 220 and the measurement means 110 based on instructions from the measurement instruction unit 124. This allows for accurate measurement of conductivity information by disconnecting the connection to the electrolytic device 230 when measuring conductivity information, and contributes to miniaturization of the device by reducing the number of parts. Note that the switching means 140 may remain connected to the pair of electrodes 220 and the measurement means 110 in the normal state.

[0036] The correction information acquisition unit 126 acquires correction information indicating the temperature correction used when calculating the hypochlorous acid concentration from the measured conductivity information. The correction information may be created by experimentally changing the temperature of the water in the electrolytic cell 210 and measuring the relationship between the temperature and concentration of the hypochlorous acid water. Alternatively, the temperature coefficient of conductivity may be used as the correction information.

[0037] The temperature coefficient of electrical conductivity is expressed by the following equation 1.

[0038]

number

[0039] α varies depending on the type of solute that dissolves in water. The inventors have found that the temperature coefficient of NaCl water (dilute saline solution) (226 * 10^(-4)) is suitable when performing temperature correction for hypochlorous acid concentration. Note that * indicates multiplication and ^ indicates exponentiation.

[0040] The concentration calculation unit 123 calculates the hypochlorous acid concentration using two conductivity data points measured before and after a single electrolysis cycle performed for a predetermined time and at a predetermined voltage. This eliminates the influence of the hardness of the water used to create the chlorine on the conversion information. Specifically, for example, when tap water is used to create chlorine-containing water, the water hardness varies depending on the region. However, by using conductivity data before and after a single electrolysis cycle, the hypochlorous acid concentration can be calculated using common conversion information regardless of the region.

[0041] As a specific calculation method, after replacing the water in the electrolytic cell 210, the difference in conductivity information before the first electrolysis is set to zero, as shown in Figure 4, and the hypochlorous acid concentration is also set to zero. Alternatively, the conductivity information can be obtained by actually performing measurements.

[0042] Next, after one electrolysis cycle, the measurement instruction unit 124 operates the applied measuring device to perform the measurement. The measurement information acquisition unit 121 acquires conductivity information (liquid resistance value) and converts it to conductivity. Based on the temperature information acquired by the measurement information acquisition unit 121 and the correction information acquired by the correction information acquisition unit 126, the corrected conductivity corresponding to the temperature is derived. Next, as shown in Equation 2 below, the corrected conductivity derived in the previous cycle is subtracted. The difference obtained by the subtraction is accumulated.

[0043]

number

[0044] The concentration calculation unit 123 calculates the hypochlorous acid concentration from the cumulative difference in conductivity based on the conversion information shown in Figure 4.

[0045] The measurement adjustment unit 127 changes the gain of the output power of the AC power supply unit 131 of the applied measuring device 112 (see step 5(a)) and changes the gain of the liquid resistance value measuring device 132 (see step 5(b)) so that the conductivity information measured by the measuring means 110 falls within a predetermined range. This allows for high-precision measurement of conductivity. The method of adjusting the gain is not particularly limited, but an example is to gradually increase the gain from a small gain and set it to a gain just before the liquid resistance value, which is the output, saturates. Furthermore, the measurement adjustment unit 127 only needs to change the gain at least once in the initial stage when the electrolytic cell 210 is filled with water containing chlorine.

[0046] The cleaning unit 128, based on water level information measured by a water level sensor 260 provided in the electrolytic cell 210, confirms that the entire pair of electrodes 220 are immersed in the chlorine-containing water stored in the electrolytic cell 210, and then switches the switching means 140 to connect the electrodes 220 to the application measuring device 112. The application measuring device 112 is then operated to clean the pair of electrodes 220. The cleaning is performed by applying an AC voltage to the electrodes 220 connected via the switching means 140 at the maximum output allowed by the application measuring device 112. This promotes the dissolution of salt crystals and other deposits deposited on the surface of the electrodes 220 connected via the switching means 140.

[0047] Next, the operation of the space sterilization device 200 will be explained. Figure 6 is a flowchart showing the operation flow of the space sterilization device 200. First, the main control device 250 confirms that the electrolytic cell 210 is full of water (S101). The cleaning unit 128 of the measurement control device 120, having obtained information from the main control device 250 indicating that the cell is full of water, controls the switching means 140 via the measurement instruction unit 124 to switch the connection so that the electrode 220 and the measuring means 110 are connected (S102), and controls the application measuring device 112 to apply an AC voltage of a predetermined power to the electrode 220 to clean the electrode 220 (S103). After that, the connection of the switching means 140 is returned to the electrolytic device 230 side, and it waits until the start signal for the electrolytic process is generated (S104).

[0048] When the electrolytic treatment start signal is generated, before the first electrolytic treatment, the measurement instruction unit 124 switches the switching means 140 to the application measurement device 112 side (S105), and the AC power supply device 131 of the application measurement device 112 applies a predetermined AC voltage to the electrode 220. The liquid resistance value measuring device 132 measures the liquid resistance value of the water in the electrolytic cell 210. The water temperature sensor 113 also measures the water temperature (S106). The measurement information acquisition unit 121 of the measurement control device 120 acquires the liquid resistance value as conductivity information and also acquires temperature information. The concentration calculation unit 123 converts the liquid resistance value to conductivity and then corrects the conductivity based on the correction information using the temperature information. The concentration calculation unit 123 stores the corrected conductivity along with the number of calculations (S107). Note that the first measurement after filling the electrolytic cell 210 with water may be omitted. If omitted, the conductivity may be stored as an initial value equivalent to that of tap water containing a predetermined amount of salt.

[0049] Next, the switching means 140 is returned to the connection between the electrolytic device 230 and the electrode 220 (S108), and the electrolytic device 230 applies a DC voltage to the electrode 220 at a predetermined output for a predetermined time, thereby performing electrolysis of the chlorine-containing water in the electrolytic cell 210 (S109). This generates hypochlorous acid water.

[0050] Based on the execution information acquired by the electrolysis execution acquisition unit 125, the measurement instruction unit 124 determines that electrolysis has been completed, and switches the switching means 140 to connect the application measuring device 112 and the electrode 220 (S110). The measurement instruction unit 124 then controls the measuring means 110 to measure the liquid resistance value, and the measurement information acquisition unit 121 acquires temperature information (S111). The concentration calculation unit 123 converts the reciprocal of the liquid resistance value into conductivity and calculates the conductivity based on the correction information. The concentration calculation unit 123 stores the corrected conductivity along with the number of calculations (S112), and then calculates the difference between the previously calculated conductivity and the currently calculated conductivity. The obtained difference is accumulated as shown in Equation 1 (S113). The concentration calculation unit 123 uses the accumulated difference and conversion information to calculate the hypochlorous acid concentration (S114), and outputs the calculated hypochlorous acid concentration to the main control device 250 (S115).

[0051] The process from electrolysis (S106) to outputting the hypochlorous acid concentration (S111) is repeated until a signal to end the electrolytic treatment is generated. For example, if the main control device 250 determines that the hypochlorous acid concentration has exceeded a predetermined concentration threshold, it may generate a signal to end the electrolytic treatment.

[0052] As described above, the hypochlorous acid water generator 100 according to this embodiment employs the AC impedance method, which involves applying an AC voltage to measure the liquid resistance value. This allows the concentration of hypochlorous acid water to be measured using the electrode 220 used for electrolysis, thus simplifying the device configuration. Furthermore, the hypochlorous acid water generator 100 has a relatively simple structure, can generate hypochlorous acid water stably over a long period, and can measure the hypochlorous acid concentration stably over a long period.

[0053] Furthermore, by calculating the hypochlorous acid concentration using the difference in conductivity before and after a single electrolysis cycle, it is possible to cancel out information related to hardness components even when the chlorine-containing water contains various hardness components or when the ratio of hardness components differs. Therefore, even when the hardness components of water differ due to regional differences, the hypochlorous acid concentration can be calculated stably and with high accuracy using a single conversion data.

[0054] Furthermore, by selecting the frequency of the applied AC voltage from a range of 1 kHz or higher and 100 kHz or lower, the liquid resistance value can be measured stably.

[0055] Furthermore, by applying a temperature correction to the conductivity based on the water temperature in the electrolytic cell 210, it is possible to calculate the hypochlorous acid concentration more accurately and with higher precision.

[0056] Furthermore, by adjusting the gain of at least one of the AC power supply and the liquid resistance measuring device 132 to a large output that does not saturate in the initial stage, highly accurate concentration measurement becomes possible.

[0057] Furthermore, by promoting the dissolution of salt crystals attached to electrode 220 through a cleaning process, the efficiency of hypochlorous acid water generation is maintained, and fluctuations in measurement results due to deposits on electrode 220 are suppressed, enabling highly accurate concentration measurement.

[0058] It should be noted that the present invention is not limited to the embodiments described above. For example, other embodiments of the present invention may be realized by arbitrarily combining the components described herein, or by excluding some of the components. Furthermore, modifications obtained by applying various modifications to the above embodiments that a person skilled in the art could conceive of without departing from the spirit of the present invention, that is, the meaning indicated by the wording in the claims, are also included in the present invention.

[0059] For example, the switching means 140 may include an electronically controllable and high-voltage resistant mechanical switch 141 and a semiconductor switch 142 that can easily interrupt and connect AC current, as shown in Figure 7. The mechanical switch 141 switches between the electrolytic device 230 and the electrode 220, and the semiconductor switch 142 switches between the applied measuring device 112 and the electrode 220. In this case, when measuring conductivity, the mechanical switch 141 is set to the open state and the semiconductor switch 142 is set to the conductive state. When performing electrolysis, the mechanical switch 141 is set to the conductive state and the semiconductor switch 142 is set to the open state.

[0060] Furthermore, when connecting the electrode 220 and the application measuring device 112 via the semiconductor switch 142, it is also possible to connect a semiconductor switch equivalent to the semiconductor switch 142 provided in the switching means 140 to the application measuring device 112 in advance, measure the ON resistance, and remove the influence of the ON resistance on the conductivity measurement by correction.

[0061] Furthermore, although the above embodiment described a case in which differences in liquid resistance (conductivity) are used to offset differences in hardness components, it is also acceptable to calculate the hypochlorous acid concentration from the liquid resistance (conductivity) without using the difference. In this case, it is also acceptable to switch and apply multiple types of conversion information corresponding to differences in water hardness.

[0062] Furthermore, it is not necessary to perform temperature correction on the liquid resistance value (conductivity). In this case, the measurement means 110 does not need to be equipped with a water temperature sensor 113, nor does it need to acquire correction information.

[0063] Furthermore, the gain can be appropriately set in advance, for example, at the time of shipment. Therefore, there are cases where the measurement control device 120 does not need to perform gain adjustment.

[0064] Furthermore, by regularly replacing electrode 220, cleaning may not be necessary in some cases.

[0065] Furthermore, although the main control unit 250 and the measurement control unit 120 have been described as separate components, they may also be integrated into a single unit. In other words, the main control unit 250 and the measurement control unit 120 can be implemented by having a single processor execute the program.

[0066] Furthermore, although we have described the case in which the hypochlorous acid water generator 100 is used in the air disinfection device 200, the hypochlorous acid water generator 100 can also be used even when hypochlorous acid water is not sprayed into the air.

[0067] Furthermore, the conversion information and correction information do not have to be stored in the memory device 102 of the measurement control device 120, but may be acquired through communication such as a network. [Explanation of Symbols]

[0068] 100 Hypochlorous Acid Water Generator 102 Storage device 110 Measurement means 112 Applied Measurement Device 113 Water temperature sensor 120 Measurement and control device 121 Measurement information acquisition section 122 Conversion information acquisition unit 123 Concentration calculation section 124 Measurement instruction section 125 Electrolysis Execution Unit 126 Correction Information Acquisition Unit 127 Measurement adjustment section 128 Cleaning Department 131 AC power supply equipment 132 Liquid Resistance Measurement Device 140 Switching means 141 Mechanical Switches 142 Semiconductor switches 200 Space sterilization device 210 Electrolytic cell 220 electrode 230 Electrolyzer 240 Diffusion means 250 Main control unit 260 Water level sensor

Claims

1. An electrolytic cell for storing water containing chlorine, A pair of electrodes arranged in an inserted state within the electrolytic cell, An electrolytic device that applies a DC voltage to a pair of electrodes and electrolyzes the chlorine-containing water to generate hypochlorous acid water, A measuring means for measuring conductivity information indicating the conductivity of hypochlorous acid water stored in the electrolytic cell, A measuring control device that controls the measuring means, The system includes a switching means for switching between the connection between the pair of electrodes and the electrolytic device and the connection between the pair of electrodes and the measuring means, The aforementioned measuring means is The device includes an application measuring device that applies an AC voltage between a pair of electrodes, The aforementioned measurement and control device is A measurement information acquisition unit that acquires conductivity information from the aforementioned measurement means, A conversion information acquisition unit that acquires conversion information showing the relationship between hypochlorous acid concentration and the conductivity information, The system includes a concentration calculation unit that calculates the hypochlorous acid concentration based on the measured conductivity information and the conversion information, The aforementioned application measuring device is, An AC voltage selected from the range of 1 kHz to 100 kHz is applied between the pair of electrodes. The aforementioned measuring means is The system includes a liquid resistance measuring device that measures the liquid resistance value between the electrodes as conductivity information. The concentration calculation unit, The hypochlorous acid concentration is calculated based on the measured liquid resistance value. Hypochlorous acid water generator.

2. The aforementioned switching means is This relay uses mechanical contacts to switch between the connection between the pair of electrodes and the electrolytic device and the connection between the pair of electrodes and the measuring means. A hypochlorous acid water generator according to claim 1.

3. The aforementioned measurement and control device is An electrolysis execution acquisition unit that acquires execution information indicating the execution of electrolysis, The system includes a measurement instruction unit that, when electrolysis is not being performed based on the execution information, switches the switching means to connect the electrodes and the measuring means, and causes the measuring means to perform conductivity information measurement, The concentration calculation unit, The difference in hypochlorous acid concentration is calculated using conductivity information measured before and after electrolysis. A hypochlorous acid water generator according to claim 1.

4. The aforementioned measurement and control device is The measurement adjustment unit includes an adjustment mechanism that adjusts at least one of the output power of the applied measuring device and the gain of the liquid resistance measuring device so that the conductivity information measured by the measuring means falls within a predetermined range. A hypochlorous acid water generator according to claim 1.

5. An electrolytic cell for storing water containing chlorine, A pair of electrodes arranged in an inserted state within the electrolytic cell, An electrolytic device that applies a DC voltage to a pair of electrodes and electrolyzes the chlorine-containing water to generate hypochlorous acid water, A measuring means for measuring conductivity information indicating the conductivity of hypochlorous acid water stored in the electrolytic cell, A measuring control device that controls the measuring means, A switching means for switching between the connection between the pair of electrodes and the electrolytic device and the connection between the pair of electrodes and the measuring means, The system includes a means for diffusing the generated hypochlorous acid water into the atmosphere, The aforementioned measuring means is The device includes an application measuring device that applies an AC voltage between a pair of electrodes, The aforementioned measurement and control device is A measurement information acquisition unit that acquires conductivity information from the aforementioned measurement means, A conversion information acquisition unit that acquires conversion information showing the relationship between hypochlorous acid concentration and the conductivity information, The system includes a concentration calculation unit that calculates the hypochlorous acid concentration based on the measured conductivity information and the conversion information, The aforementioned application measuring device is, An AC voltage selected from the range of 1 kHz to 100 kHz is applied between the pair of electrodes. The aforementioned measuring means is The system includes a liquid resistance measuring device that measures the liquid resistance value between the electrodes as conductivity information. The concentration calculation unit, The hypochlorous acid concentration is calculated based on the measured liquid resistance value. A space sterilization device.

6. A method for measuring the concentration of hypochlorous acid, which is generated by electrolyzing chlorine-containing water stored in an electrolytic cell using a pair of electrodes to which a voltage is applied, When electrolysis is not being performed, the measurement instruction unit uses a switching mechanism to switch the connection between the electrodes and the measuring means, and applies an AC voltage selected from a range of 1 kHz to 100 kHz to the measuring means between the pair of electrodes, thereby measuring the liquid resistance value between the electrodes as conductivity information. The measurement means, which measures conductivity information indicating the conductivity of hypochlorous acid water stored in the electrolytic cell, is used by the measurement information acquisition unit to acquire conductivity information. The conversion information acquisition unit acquires conversion information showing the relationship between the hypochlorous acid concentration and the conductivity information. Based on the acquired liquid resistance value and the conversion information, the concentration calculation unit calculates the hypochlorous acid concentration. Method for measuring hypochlorous acid concentration.

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