JP2024043371A - Hypochlorous acid water generator, space sterilization device, and hypochlorous acid concentration measurement method - Google Patents

Abstract

[Problem] The concentration of hypochlorous acid is measured using electrodes used for electrolysis. [Solution] A hypochlorous acid water generator comprising an electrolytic cell 210, an electrolytic device 230 that applies a DC voltage to a pair of electrodes 220 to electrolyze chlorine-containing water to generate hypochlorous acid water, a measuring means 110 that measures conductivity information indicating the conductivity of the hypochlorous acid water, a measurement control device 120 that controls the measuring means 110, and a switching means 140 that switches between the connection between the electrodes 220 and the electrolytic device 230 and the connection between the electrodes 220 and the measuring means 110, the measuring means 110 comprising an application measuring device 112 that applies an AC voltage between the pair of electrodes 220, and the measurement control device 120 comprising a measurement information acquisition unit 121 that acquires the conductivity information from the measuring means 110, a conversion information acquisition unit 122 that acquires conversion information indicating the relationship between the 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 Figure] Figure 1

Description

The present invention relates to a hypochlorous acid water generating device, a space sterilization device, and a method for measuring hypochlorous acid concentration.

Patent Document 1 describes a so-called Polaro measurement technique that measures the concentration of hypochlorous acid water based on the electrochemical reduction current of hypochlorous acid.

Japanese Patent Application Publication No. 2011-7508

Conventionally, hypochlorous acid water generators have a pair of electrodes for electrolysis. It is possible to measure the concentration of hypochlorous acid using these electrodes, but it is difficult to adopt polarographic measurement technology, which causes fluctuations in the measured value of the concentration of hypochlorous acid water due to contamination of the electrodes used for measurement. In addition, adopting polarographic measurement technology makes handling complicated, such as requiring cleaning of the electrodes before measurement, and there are cost issues, such as the need to use precious metals as the material for the electrodes.

As a result of intensive research and experiments based on the above-mentioned problem, the inventor discovered that the electrical conductivity of hypochlorous acid water, which can be stably measured, is a relatively accurate indicator of the concentration of hypochlorous acid water. Ta. Furthermore, they discovered that the concentration of hypochlorous acid can be accurately measured using an electrode that generates hypochlorous acid water. The present invention was made based on the inventor's knowledge, and provides a hypochlorous acid water generator, a space sterilization device, and a hypochlorous acid water generator that can measure the concentration of hypochlorous acid water with a simple configuration. The purpose is to provide a method for measuring acid concentration.

In order to achieve the above object, a hypochlorous acid water generator according to one aspect of the present invention includes an electrolytic cell that stores water containing chlorine, and a pair of electrodes that are inserted into the electrolytic cell. an electrolytic device that applies a DC voltage to the pair of electrodes to electrolyze the water containing chlorine to generate hypochlorous acid water; a measuring means for measuring conductivity information indicating conductivity, a measurement control device for controlling the measuring means, a connection between a pair of the electrodes and the electrolytic device, and a connection between a pair of the electrodes and the measuring means. a switching device, the measuring device includes an application measuring device that applies an alternating current voltage between the pair of electrodes, and the measurement control device includes a measurement information acquisition unit that acquires conductivity information from the measuring device. and a conversion information acquisition unit that acquires conversion information indicating the relationship between hypochlorous acid concentration and the conductivity information, and a concentration that calculates the hypochlorous acid concentration based on the measured conductivity information and the conversion information. A calculation section.

Further, the space sterilization device according to one aspect of the present invention includes an electrolytic cell that stores water containing chlorine, a pair of electrodes inserted into the electrolytic cell, and a DC voltage applied to the pair of electrodes. an electrolytic device that applies chlorine and electrolyzes the water containing chlorine to generate hypochlorous acid water, and measures conductivity information indicating the conductivity of the hypochlorous acid water stored in the electrolytic cell. a measuring means, a measurement control device for controlling the measuring means, a switching means for switching between the connection between the pair of the electrodes and the electrolytic device and the connection between the pair of the electrodes and the measuring means; diffusion means for diffusing chloric acid water into the atmosphere; the measurement means includes an application measurement device that applies an alternating current voltage between the pair of electrodes; and the measurement control device a measurement information acquisition unit that acquires conductivity information; a conversion information acquisition unit that acquires conversion information indicating the relationship between the hypochlorous acid concentration and the conductivity information; A concentration calculation unit that calculates a hypochlorous acid concentration.

Further, the method for measuring hypochlorous acid concentration according to one aspect of the present invention includes hypochlorous acid generated by electrolyzing chlorine-containing water stored in an electrolytic tank using a pair of electrodes to which a voltage is applied. A hypochlorous acid concentration measuring method for measuring the concentration of hypochlorous acid, wherein when electrolysis is not being performed, the measurement instruction section uses a switching means to switch the connection between the electrode and the measuring means to conduct electricity to the measuring means. The measurement information acquisition unit acquires the conductivity information from the measuring means that measured the conductivity information indicating the conductivity of the hypochlorous acid water stored in the electrolytic cell. A conversion information acquisition unit acquires conversion information indicating a relationship between the 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.

The above-mentioned hypochlorous acid concentration measurement method can be realized as a program for causing a computer to execute the method. Alternatively, the method can be realized as a computer-readable recording medium storing the program.

According to the present invention, the hypochlorous acid concentration of generated hypochlorous acid water can be measured with a simple device configuration.

FIG. 1 is a diagram simply showing the space sterilization device according to the present embodiment from the side. FIG. 2 is a block diagram showing the functional configuration of a measurement control device. It is a graph showing the relationship between the hypochlorous acid concentration and the conductivity of hypochlorous acid water. It is a graph showing the relationship between the accumulation of differences in conductivity and hypochlorous acid concentration. FIG. 4 is a block diagram of a liquid resistance measurement circuit provided in the measurement means. It is a flowchart which shows the flow of space sterilization device operation. FIG. 13 is a diagram showing another example of the switching means.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a hypochlorous acid water generating device, a space sterilization device, and a hypochlorous acid concentration measuring method according to the present invention will be described with reference to the drawings. Note that the following embodiments are provided as an example to explain the present invention, and are not intended to limit the present invention. For example, the shapes, structures, materials, components, relative positional relationships, connection states, numerical values, formulas, contents of each step in the method, order of each step, etc. shown in the following embodiments are merely examples. It may contain content not listed. Furthermore, although geometric expressions such as parallel and perpendicular are sometimes used, these expressions do not indicate mathematical rigor and include substantially permissible errors, deviations, and the like. Furthermore, expressions such as "simultaneously" and "identical" also include a substantially permissible range.

The drawings are schematic diagrams in which emphasis, omission, or adjustment of proportions has been appropriately made in order to explain the present invention, and differ from the actual shapes, positional relationships, and proportions. The X-axis, Y-axis, and Z-axis that may be shown in the drawings indicate orthogonal coordinates that have been arbitrarily set in order to explain the drawings. In other words, the Z-axis is not necessarily an axis along the vertical direction, and the X-axis and Y-axis are not necessarily on a horizontal plane.

Furthermore, hereinafter, multiple inventions may be comprehensively described as one embodiment. Further, some of the contents described below are explained as optional components related to the present invention.

Furthermore, the flowchart is just an example, and even if the process flow is different, such as in a different order of processing, in which a plurality of processes are integrated, or in which one process is separated, it is included in the embodiment of the present invention.

FIG. 1 is a diagram schematically showing a space sterilization device 200 according to the present embodiment from the side. The space sterilization device 200 releases hypochlorous acid water into the space. Moreover, the space sterilization device 200 introduces the atmosphere in the space into the hypochlorous acid water. The target space is a closed space such as the indoor space of a building. Specifically, examples of the space include a living space in a general home, an indoor space in a hospital or a nursing care facility, and the like. Note that the space does not need to be a completely closed space and may be connected to the outdoors. Moreover, the space may be not only a space inside a building but also a space inside a moving body such as a train or a car.

Hypochlorous acid water has sterilizing and deodorizing effects. Specifically, hypochlorous acid water has an oxidizing effect, and sterilizes and deodorizes by decomposing floating bacteria in the space, bacteria adhering to objects, or odor substances through oxidation. Note that the term "sterilization" is used for convenience in the present specification and claims, and includes meanings such as "sterilization." In addition, "bacteria" is described as including viruses, molds, etc.

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

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 water containing chlorine include water in which salt is dissolved.

The electrodes 220 are a pair of conductive members inserted into the chlorine-containing water stored in the electrolytic cell 210. Although the shape of the electrode 220 is not particularly limited, in the case of this embodiment, it is a rectangular plate shape (band shape). The electrodes 220 are arranged so that their respective 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 is conductive. For example, the electrode 220 may have a structure in which the surface of a conductive base material is coated with a catalyst layer. Examples of the conductive base material include simple metals such as titanium, iron, copper, niobium, and tantalum, or alloys thereof. In consideration of ease of processing during manufacturing or manufacturing cost, the material of the conductive base material is preferably titanium or a titanium alloy. The catalyst layer can be exemplified by a catalyst containing platinum, iridium, or the like. Other mixtures contained in the catalyst layer may be in any metal state such as metals, alloys, metal oxides, etc., such as lead, gold, nickel, copper, silver, iron, palladium, ruthenium, rhodium, carbon, etc. can be mentioned.

The electrolysis device 230 is a DC power supply device that applies a predetermined DC voltage between a pair of electrodes 220. In the electrolytic device 230, whether or not to apply a voltage to the pair of electrodes 220, that is, whether to apply a voltage to the pair of electrodes 220 is selected on or off under the control of the main controller 250.

The diffusion means 240 is a cylindrical member that rotates around the tube axis (left and right direction in FIG. 1). Part of the periphery of the diffusion means 240 is periodically immersed in the hypochlorous acid water stored in the electrolytic cell 210, and the water is raised above the liquid level of the hypochlorous acid water by utilizing capillary action or the like. By passing air between the hypochlorous acid water raised above the liquid level, minute droplets of hypochlorous acid water are diffused into the atmosphere. Bacteria (including viruses, mold, etc.) present in the air are sterilized (including inactivation of viruses, mold, etc.) by contact with the hypochlorous acid water raised by the diffusion means 240. They are also sterilized by contact with the hypochlorous acid water diffused into the atmosphere.

The main control device 250 is a device that includes a processor and controls the space sterilization device 200 by causing the processor to execute a program. In the case of this embodiment, main controller 250 acquires the hypochlorous acid concentration in electrolytic cell 210 from hypochlorous acid water generator 100, which will be described later, and performs electrolysis so that the hypochlorous acid concentration is constant. Control device 230. Here, the hypochlorous acid concentration means the total concentration of hypochlorous acid and hypochlorite ions. The main controller 250 also acquires water level information indicating the water level from a water level sensor 260 provided in the electrolyzer 210, and if the water level in the electrolyzer 210 has not reached a predetermined water level threshold, the main controller 250 control so that it does not operate.

The switching means 140 switches between the connection between the pair of electrodes 220 and the electrolyzer 230 and the connection between the pair of electrodes 220 and the measurement means 110. In the case of this embodiment, the switching means 140 is a relay that exclusively switches the connection between the pair of electrodes 220 and the electrolyzer 230 and the connection between the pair of electrodes 220 and the measuring means 110 using mechanical contacts. has been adopted. Thereby, it is possible to prevent a problem from occurring in the measuring means 110 due to the current flowing into the measuring means 110 when generating hypochlorous acid water. Furthermore, when measuring the concentration of hypochlorous acid, it is possible to eliminate the influence of the electrolytic device 230 and perform accurate measurement.

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 is equipped with a measuring means 110 and a measurement control device 120.

The measuring means 110 is a device that measures conductivity information indicating the conductivity of the hypochlorous acid water stored in the electrolytic cell 210, can be connected to the electrode 220 via the switching means 140, and is equipped with an application measuring device 112. In this embodiment, the measuring means 110 is equipped with a water temperature sensor 113 that measures temperature information indicating the temperature of the water stored in the electrolytic cell 210.

The application and measurement device 112 includes an AC power supply device 131 (see FIG. 5) that applies a predetermined AC voltage between a pair of electrodes 220 connected via a switching means 140. Further, the application measuring device 112 includes a liquid resistance value measuring device 132 (see FIG. 5) that measures the liquid resistance value between the pair of electrodes 220 as conductivity information. The application and measurement device 112 selects whether or not to apply an AC voltage to the electrodes 220, that is, whether to apply an AC voltage to the pair of electrodes 220 or not, under the control of the measurement control device 120. It is preferable that the frequency of the AC voltage applied between the pair of electrodes 220 by the application and measurement device 112 is selected from a range of 1 kHz or more and 100 kHz or less. By applying the AC voltage in the relatively high frequency range, the liquid resistance value measuring device 132 measures the liquid resistance value without an imaginary term when calculating the liquid resistance value of hypochlorous acid water using the AC impedance method. Resistance value can be measured. In other words, the inventor found that by using the AC impedance method at a frequency in the above 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. I'm finding it. Although the application and measurement device 112 includes an AC power supply device 131 that applies an AC voltage, the application and 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 control the alternating current.

FIG. 2 is a block diagram showing the functional configuration of the measurement control device 120. The measurement control device 120 includes a processor, and controls the timing at which the application and measurement device 112 applies an AC voltage to the electrodes 220 connected via the pair of switching means 140 by causing the processor to execute a program. Furthermore, conductivity information indicating the conductivity of hypochlorous acid water obtained by applying an alternating current voltage is acquired. The measurement control device 120 includes a measurement information acquisition section 121, a conversion information acquisition section 122, and a concentration calculation section 123 as processing sections. In the case of this embodiment, the measurement control device 120 includes an electrolysis execution acquisition section 125, a measurement instruction section 124, a correction information acquisition section 126, a measurement adjustment section 127, and a cleaning section 128.

The measurement information acquisition unit 121 acquires conductivity information from the measurement means 110. The electrical conductivity information acquired from the measuring means 110 is not particularly limited, and may be information such as the electrical conductivity of hypochlorous acid water (electrical conductivity) or information from which the electrical conductivity can be derived by calculation. For example, the conductivity information may be a liquid resistance value of hypochlorous acid water. The measurement information acquisition unit 121 may obtain 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 obtained liquid resistance value.

In the case of this embodiment, the measurement information acquisition unit 121 also acquires temperature information from the water temperature sensor 113 included in the measurement means 110.

The conversion information acquisition unit 122 acquires conversion information indicating the relationship between hypochlorous acid concentration and conductivity information. The inventor stored water containing chlorine (hereinafter referred to as water in this paragraph) in an electrolytic cell 210, and electrolyzed the water at a predetermined voltage for a predetermined time. When electrolysis is not performed at all (0 times), the hypochlorous acid concentration and the conductivity of water are measured, and each time water electrolysis is performed under the above conditions, the hypochlorous acid concentration is measured. and the conductivity of water. Based on the above experiments, the inventor has found that the hypochlorous acid concentration and the conductivity of water are in an inversely proportional relationship, as shown in FIG. 3. Note that m in FIG. 3 is an integer. Moreover, the description of specific numerical values of hypochlorous acid concentration and electrical conductivity is omitted.

From the above, the inventor created conversion information as a function, which shows the relationship between hypochlorous acid concentration and electrical conductivity, as shown in the graph of FIG. 4. In the case of this embodiment, the conversion information acquisition unit 122 acquires the function stored in the storage device 102 included in the measurement control device 120 as conversion information. Note that the vertical axis of the graph shown in FIG. 4 is the difference in electrical conductivity. The difference in conductivity will be described later.

The concentration calculation unit 123 calculates the hypochlorous acid concentration based on the conductivity information acquired from the measuring means 110 and the conversion information acquired by the conversion information acquisition unit 122. The concentration calculation unit 123 outputs the calculated hypochlorous acid concentration to the main controller 250. Note that a specific description of the concentration calculation section 123 will be given later.

The electrolysis execution acquisition unit 125 acquires execution information indicating the execution state of electrolysis executed by the electrolysis device 230 and the electrodes 220 from the main control device 250. Thereby, the electrolysis execution acquisition unit 125 can grasp from the execution information whether electrolysis is being executed or not being executed in the electrolytic cell 210.

The measurement instruction unit 124 controls the measurement unit 110 to switch the switching means 140 to the connection between 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, and to measure the electrical conductivity information. The switching means 140 maintains the pair of electrodes 220 and the electrolysis device 230 in a connected state in the normal state, and switches to the connection between the electrodes 220 and the measurement means 110 based on an instruction from the measurement instruction unit 124. This cuts off the connection with the electrolysis device 230 when measuring electrical conductivity information, making it possible to accurately measure electrical conductivity information, and contributing to miniaturization of the device by reducing the number of parts. Note that the switching means 140 may be in the normal state where the pair of electrodes 220 and the measurement means 110 are connected.

The correction information acquisition unit 126 acquires correction information indicating temperature correction 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. Further, the temperature coefficient of conductivity may be used as correction information.

The temperature coefficient of conductivity is expressed by Equation 1 below.

ｔ：次亜塩素酸水の温度（温度情報）
Ｋ：電導度
α：温度係数

t: Temperature of hypochlorous acid water (temperature information)
K: Conductivity α: Temperature coefficient

α varies depending on the type of solute dissolved in water. The inventor has found that the temperature coefficient (226*10^(-4)) of NaCl water (dilute salt water) is suitable for temperature correction of hypochlorous acid concentration. Note that * indicates multiplication, and ^ indicates exponentiation.

The concentration calculation unit 123 calculates the hypochlorous acid concentration using two pieces of conductivity information measured before and after one electrolysis run performed for a predetermined time and at a predetermined voltage. This makes it possible to exclude the influence of the hardness of water containing chlorine on the conversion information. Specifically, for example, when tap water is used to create water containing chlorine, the hardness of the water varies depending on regional differences, but by using conductivity information before and after a single electrolysis process, it is possible to determine where the water is. Hypochlorous acid concentration can be calculated using conversion information that is common across regions.

As a specific calculation method, the difference in conductivity information after replacing the water in the electrolytic cell 210 and before the first electrolysis is set to zero, as shown in FIG. 4, and the hypochlorous acid concentration is also set to zero. shall be. Note that the conductivity information may be obtained by actually performing the measurement.

Next, after performing one electrolysis, the measurement instruction unit 124 operates the application and measurement device to perform measurement. The measurement information acquisition unit 121 acquires conductivity information (liquid resistance value) and converts it into conductivity. For the obtained conductivity, a corrected conductivity corresponding to the temperature is derived based on the temperature information acquired by the measurement information acquisition section 121 and the correction information acquired by the correction information acquisition section 126. Next, as shown in Equation 2 below, the corrected conductivity derived in the previous round is subtracted. Accumulate the differences obtained by subtraction.

ｎは、電気分解の回数を示す。
電導度（ｎ）は、ｎ回目の電気分解後の電導度を意味している。
Ｎは、電気分解の総回数を示す。

n indicates the number of times of electrolysis.
The electrical conductivity (n) means the electrical conductivity after the n-th electrolysis.
N indicates the total number of electrolysis.

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

The measurement adjustment unit 127 changes the gain of the output power of the AC power supply device 131 included in the application measurement device 112 so that the conductivity information measured by the measurement means 110 falls within a predetermined range ((a) in FIG. 5). (see step (b) in FIG. 5), and at least one of changing the gain of the liquid resistance value measuring device 132 (see step (b) in FIG. 5). According to this, conductivity can be measured with high accuracy. The gain adjustment method is not particularly limited, but an example may be a method in which the gain is gradually increased from a small gain and set to a gain just before the liquid resistance value, which is the output, is saturated. Further, the measurement adjustment unit 127 may change the gain at least once in the initial stage of filling the electrolytic cell 210 with water containing chlorine.

In the cleaning section 128, the entire pair of electrodes 220 are immersed in chlorine-containing water stored in the electrolytic cell 210 based on water level information measured by a water level sensor 260 provided in the electrolytic cell 210. After confirming this, the switching means 140 is switched to connect the electrode 220 and the application/measurement device 112. Then, the application and measurement device 112 is operated to clean the pair of electrodes 220. Cleaning is performed by applying an alternating current voltage to the electrodes 220 connected via the switching means 140 at the maximum output allowed by the application and measurement device 112. Thereby, dissolution of salt crystals etc. deposited on the surface of the electrode 220 connected via the switching means 140 can be promoted.

Next, the operation of the space sterilization device 200 will be explained. FIG. 6 is a flowchart showing the flow of operations of the space sterilization device 200. First, the main controller 250 confirms that the electrolytic cell 210 is full of water (S101). The cleaning unit 128 of the measurement control device 120 that has acquired the information indicating that the water is full from the main control device 250 controls the switching unit 140 via the measurement instruction unit 124 so that the electrode 220 and the measurement unit 110 are connected. The connection is switched (S102), and the application and measurement device 112 is controlled to apply an AC voltage of a predetermined power to the electrode 220, thereby cleaning the electrode 220 (S103). Thereafter, the connection of the switching means 140 is returned to the electrolysis device 230 side, and the process waits until an electrolytic treatment start signal is generated (S104).

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 and measurement device 112 side (S105), and the AC power supply device 131 of the application and measurement device 112 switches the electrode A predetermined AC voltage is applied to 220. The liquid resistance value measuring device 132 measures the liquid resistance value of water in the electrolytic cell 210. Furthermore, the water temperature sensor 113 measures the water temperature (S106). The measurement information acquisition unit 121 of the measurement control device 120 acquires a liquid resistance value as conductivity information and also acquires temperature information. After converting the liquid resistance value into conductivity, the concentration calculation unit 123 corrects the conductivity based on correction information using temperature information. The concentration calculation unit 123 stores the corrected conductivity together 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 electrical conductivity may be stored as the initial value of electrical conductivity equivalent to tap water containing a predetermined amount of salt.

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

When the measurement instruction unit 124 determines that the electrolysis has ended based on the execution information acquired by the electrolysis execution acquisition unit 125, the measurement instruction unit 124 switches the switching means 140 to connect the application measurement device 112 and the electrode 220 (S110). Then, the measurement instruction unit 124 controls the measurement means 110 to measure the liquid resistance value, and the measurement information acquisition unit 121 acquires the temperature information (S111). The concentration calculation unit 123 converts the liquid resistance value into an electric conductivity by taking the inverse number of times, and calculates the electric conductivity based on the correction information. The concentration calculation unit 123 stores the corrected electric conductivity together with the number of calculations (S112). Then, it calculates the difference between the electric conductivity calculated last time and the electric conductivity calculated this time. In addition, it accumulates the obtained difference as shown in Equation 1 (S113). The concentration calculation unit 123 uses the accumulated difference and the conversion information to calculate the hypochlorous acid concentration (S114), and outputs the calculated hypochlorous acid concentration to the main control unit 250 (S115).

The above steps from electrolysis (S106) to outputting the hypochlorous acid concentration (S111) are repeated until an electrolytic treatment end signal is generated. For example, when main controller 250 determines that the hypochlorous acid concentration exceeds a predetermined concentration threshold, it may generate an electrolytic treatment end signal.

As described above, according to the hypochlorous acid water generator 100 according to the present embodiment, by adopting the AC impedance method in which the liquid resistance value is measured by applying an AC voltage, the electrode 220 used for electrolysis The concentration of hypochlorous acid water can be measured using this method, and the device configuration can be simplified. Furthermore, the hypochlorous acid water generator 100 has a relatively simple structure, can generate hypochlorous acid water stably over a long period of time, and can measure hypochlorous acid concentration stably over a long period of time. can.

In addition, by calculating the hypochlorous acid concentration using the difference in conductivity before and after one electrolysis, it is possible to calculate the hypochlorous acid concentration when water containing chlorine contains various hardness components or when the content ratio of hardness components is different. Even in this case, the difference in conductivity can be used to cancel out the information related to the hardness component. Therefore, even if the water hardness component differs due to regional differences, the hypochlorous acid concentration can be calculated stably and with high accuracy using one conversion information.

Furthermore, by selecting the frequency of the applied alternating current voltage from a range of 1 kHz or more and 100 kHz or less, the liquid resistance value can be stably measured.

Moreover, by adding temperature correction to the conductivity based on the water temperature in the electrolytic cell 210, it is possible to calculate the hypochlorous acid concentration with more accuracy and precision.

In addition, highly accurate concentration measurement is possible by adjusting the gain of at least one of the AC power supply device and the liquid resistance value measuring device 132 to provide a large output that does not saturate the output in the initial stage.

In addition, by promoting the dissolution of salt crystals attached to the electrode 220 through a cleaning process, the generation efficiency of hypochlorous acid water is maintained, and fluctuations in measurement results due to deposits on the electrode 220 are suppressed, resulting in high precision. Concentration measurement becomes possible.

Note that the present invention is not limited to the above embodiments. For example, the embodiments of the present invention may be realized by arbitrarily combining the components described in this specification or by excluding some of the components. The present invention also includes modifications obtained by making various modifications to the above-described embodiments that a person skilled in the art can conceive without departing from the gist of the present invention, that is, the meaning of the words written in the claims. It will be done.

For example, as shown in FIG. 7, the switching means 140 may include a mechanical switch 141 that can be electronically controlled and withstands high voltage, and a semiconductor switch 142 that can easily cut off and connect alternating current. The mechanical switch 141 opens and closes the electrolytic device 230 and the electrode 220, and the semiconductor switch 142 opens and closes the voltage and measurement device 112 and the electrode 220. In this case, when measuring the conductivity, the mechanical switch 141 is opened and the semiconductor switch 142 is turned on. When performing electrolysis, the mechanical switch 141 is turned on and the semiconductor switch 142 is opened.

In addition, when connecting the electrode 220 and the voltage measurement device 112 via the semiconductor switch 142, a semiconductor switch equivalent to the semiconductor switch 142 included in the switching means 140 is connected to the voltage measurement device 112 in advance, and the ON resistance is measured. Therefore, the influence of ON resistance on conductivity measurement may be removed by correction.

In addition, in the above embodiment, the case where the difference in hardness components is canceled out using the difference in liquid resistance value (electrical conductivity) has been explained, but the hypochlorous acid concentration is calculated from the liquid resistance value (electrical conductivity) without using the difference. It is okay to calculate. In this case, multiple types of conversion information corresponding to differences in water hardness may be switched and applied.

Furthermore, it is not necessary to perform temperature correction on the liquid resistance value (conductivity). In this case, the measuring means 110 does not need to include the water temperature sensor 113 and does not need to acquire correction information.

Further, by setting the gain appropriately in advance at the time of shipment, for example, the measurement control device 120 may not need to adjust the gain.

Further, cleaning may not be necessary if the electrode 220 is replaced periodically.

In addition, although the main control device 250 and the measurement control device 120 have been described as separate entities, the main control device 250 and the measurement control device 120 may be integrated. In other words, the main control device 250 and the measurement control device 120 may be realized by having a single processor execute a program.

In addition, although the case where the hypochlorous acid water generator 100 is used as the space sterilization device 200 has been described, the hypochlorous acid water generator 100 can also be used when hypochlorous acid water is not sprayed in the space. .

Further, the conversion information and correction information may be acquired through communication such as a network instead of being stored in the storage device 102 included in the measurement control device 120.

100 Hypochlorous acid water generator 102 Storage device 110 Measuring means 112 Application measuring device 113 Water temperature sensor 120 Measurement control device 121 Measurement information acquisition section 122 Conversion information acquisition section 123 Concentration calculation section 124 Measurement instruction section 125 Electrolysis execution acquisition section 126 Correction information acquisition section 127 Measurement adjustment section 128 Cleaning section 131 AC power supply device 132 Liquid resistance value measuring device 140 Switching means 141 Mechanical switch 142 Semiconductor switch 200 Space sterilization device 210 Electrolytic cell 220 Electrode 230 Electrolytic device 240 Diffusion means 250 Main control device 260 Water level sensor

Claims (7)

An electrolytic cell for storing chlorine-containing water;
A pair of electrodes inserted into the electrolytic cell;
An electrolysis device that applies a DC voltage to a pair of the electrodes to electrolyze 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 measurement control device for controlling the measuring means;
a switching means for switching between a connection between the pair of electrodes and the electrolysis device and a connection between the pair of electrodes and the measurement means,
The measuring means is
An application and measurement device is provided that applies an AC voltage between the pair of electrodes,
The measurement control device includes:
A measurement information acquisition unit that acquires electrical conductivity information from the measurement means;
A conversion information acquisition unit that acquires conversion information indicating a relationship between the hypochlorous acid concentration and the electrical conductivity information;
A concentration calculation unit that calculates a hypochlorous acid concentration based on the measured conductivity information and the conversion information;
A hypochlorous acid water generating device equipped with: The application measurement device includes:
Applying an alternating current voltage selected from a range of 1 kHz or more and 100 kHz or less between the pair of electrodes,
The measuring means includes:
A liquid resistance value measuring device that measures a liquid resistance value between the electrodes as conductivity information, and the concentration calculation unit includes:
The hypochlorous acid water generator according to claim 1, wherein the hypochlorous acid concentration is calculated based on the measured liquid resistance value. The switching means is
Hypochlorous acid water generation according to claim 1 or 2, wherein the relay is a relay that uses mechanical contacts to switch the connection between the pair of electrodes and the electrolyzer and the connection between the pair of electrodes and the measuring means. Device. The measurement control device includes:
an electrolysis execution acquisition unit that acquires execution information indicating execution of electrolysis;
a measurement instruction section that switches the switching means to connect the electrode and the measuring means when electrolysis is not being performed based on the execution information, and causes the measuring means to measure the conductivity information;
The concentration calculation unit includes:
The hypochlorous acid water generating device according to claim 1, wherein the difference in hypochlorous acid concentration is calculated using conductivity information measured before and after performing electrolysis. The measurement control device includes:
Claim 2, further comprising a measurement adjustment section that adjusts at least one of the output power of the application and measurement device and the gain of the liquid resistance value measurement device so that the conductivity information measured by the measurement means falls within a predetermined range. The hypochlorous acid water generator described in . An electrolytic tank that stores water containing chlorine,
a pair of electrodes inserted into the electrolytic cell;
an electrolysis device that applies a DC voltage to the pair of electrodes and electrolyzes the water containing chlorine to generate hypochlorous acid water;
Measuring means for measuring conductivity information indicating the conductivity of the hypochlorous acid water stored in the electrolytic cell;
a measurement control device that controls the measurement means;
switching means for switching between a connection between a pair of the electrodes and the electrolyzer and a connection between the pair of electrodes and the measurement means;
A diffusion means for diffusing the generated hypochlorous acid water into the atmosphere,
The measuring means includes:
comprising an application measuring device that applies an alternating voltage between the pair of electrodes,
The measurement control device includes:
a measurement information acquisition unit that acquires conductivity information from the measurement means;
a conversion information acquisition unit that acquires conversion information indicating the relationship between hypochlorous acid concentration and the conductivity information;
a concentration calculation unit that calculates a hypochlorous acid concentration based on the measured conductivity information and the conversion information;
A space sterilization device equipped with. A hypochlorous acid concentration measuring method for measuring the concentration of hypochlorous acid generated by electrolyzing chlorine-containing water stored in an electrolytic tank using a pair of voltage-applied electrodes, the method comprising:
When electrolysis is not being performed, the measurement instruction unit uses a switching means to switch the connection between the electrode and the measuring means and causes the measuring means to measure the conductivity information;
A measurement information acquisition unit acquires conductivity information from the measuring means that measures conductivity information indicating the conductivity of 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,
A hypochlorous acid concentration measuring method, wherein a concentration calculating section calculates a hypochlorous acid concentration based on the acquired conductivity information and the conversion information.

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