JP3484762B2 - Electrolyzed water generator - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolyzed water generator for electrolyzing tap water or the like to continuously generate alkaline ionized water and acidic ionized water.

[0002]

2. Description of the Related Art Conventionally, an electrolyzed water generating apparatus as shown in FIG. 12 has been provided. This is a filter medium 31 made of activated carbon.
Water purifier 3 provided with a filter medium 32 formed of a hollow fiber membrane
And an electrolytic bath 2, and two types of electrodes 21, 22 are arranged in the electrolytic bath 2 in a state of being partitioned by an electrolytic diaphragm 20.

The water sent to the water purifier 3 from the switching unit 98 attached to the tap water faucet 99 is purified in the water purifier 3, and then electrolysis in which a DC voltage is applied to the electrodes 21 and 22. The alkaline ionized water is sent to the bath 2 and, on the side of the electrode serving as the cathode, the alkaline ionized water
Acidic ionized water is generated on the side of the electrode serving as the anode.
Of these two types of ionized water, the main use water (generally, alkaline ionized water used for beverages) is sent out from the discharge port 23, and the sub-use water (acidic ion water) is sent from the discharge port 24 to the drainage port 64. To be

The voltage application to the electrodes 21, 22 of the electrolytic cell 2 is started by a pressure detection switch PS having a diaphragm 68 installed in a water channel connecting the switching unit 98 and the water purifier 3. Further, the water channel connecting the water purifier 3 and the electrolysis tank 2 is also connected to the drain port 64, but since the ball valve 66 is closed by the water pressure, the water going to the electrolysis tank 2 goes to the drain port 64. There is no direct flow.

When the water supply from the switching unit 98 is stopped, the pressure detecting switch PS is turned off and the electrolytic cell 2
The electricity to the electrodes 21 and 22 is cut off, and the water in the electrolytic cell 2 is discharged to the drain port 64 through the ball valve 66 which is open because there is no water pressure difference between the front and the back. In addition, in the electrolysis tank 2, the electrode 2 is subjected to long-term electrolysis.
While scales are deposited on the surface of 1 and 22,
Since this scale reduces the electrolysis ability, when the water supply is stopped and the water in the electrolytic cell 2 is drained, the voltage application to the electrodes 21 and 22 of the electrolytic cell 2 is immediately stopped. Instead, for example, the scale is eluted by performing a reverse polarity electrolysis in which a voltage having a reverse polarity to that before is applied to the electrodes 21 and 22 for about 30 seconds, for example.

Here, in the above-mentioned one, in order to confirm the pH value of the electrolyzed water actually discharged, a simple analysis with a reagent or the like must be separately performed, and the p
In order to obtain electrolyzed water with an H value, it is necessary to manually adjust the set voltage, flow rate, etc., and the electrolyzed water with the desired pH value can be reliably obtained, including the labor required to confirm the pH value. It wasn't something.

For this purpose, a pH sensor for continuously measuring the pH value of the discharged electrolyzed water is provided, and the pH value obtained from this pH sensor is compared with the target pH value to apply the electrolysis voltage to the electrolytic cell. What has been proposed to feedback control is proposed.

[0008]

However, in the conventional feedback control, regardless of the target pH value, uniform electrolytic voltage control was performed based on the difference between the target pH value and the current pH value. That is, although there is a difference in the rise of pH value change with respect to voltage change between alkaline ionized water, weakly acidic ionized water and strongly acidic ionized water, feedback control was performed by ignoring this difference. It took a long time to converge to the pH value.

The present invention has been made in view of the above circumstances, and its main object is to provide an electrolyzed water generator capable of reliably and promptly obtaining electrolyzed water having a desired pH value. However, another object of the present invention is to provide an electrolyzed water generation apparatus which has few problems due to deterioration of the pH sensor.

[0010]

SUMMARY OF THE INVENTION In the present invention, however, an electrolyzer for producing alkaline ionized water and acidic ionized water by electrolysis and discharging the electrolyzed water separately, and a pH value of the electrolyzed water are continuously adjusted. In the electrolyzed water producing apparatus including a pH sensor for measuring the pH value and a control circuit for performing feedback control of the electrolysis voltage applied to the electrolytic cell by comparing the pH value obtained from the pH sensor with the target pH value , Target pH
Together and performs feedback control by applying a voltage based on the voltage -pH characteristics set according to the value, control
The control circuit has a voltage-pH characteristic set according to the target pH value.
-Based voltage application is maintained for a certain period of time, during which pH changes
After predicting the pH value after a predetermined time from the
The voltage difference ΔV corresponding to the difference ΔpH from the pH value is the above voltage −
Obtained from pH characteristics and subtracted the voltage difference ΔV from the current voltage
The main characteristic is that the voltage is the next applied voltage .

[0011]

According to the present invention, p of electrolyzed water actually discharged is
In feedback-controlling the electrolysis voltage so that the H value becomes the desired pH value, the control suitable for the rising characteristic with respect to the voltage change of the target pH value is performed, so that the convergence to the target pH value is made early.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the illustrated embodiments. As shown in FIG. 2, this electrolyzed water producing apparatus includes an electrolytic cell 2, a backwash unit 4, switching valves 5 and 6. The flow rate adjusting valve 65, the pH sensor 7, the calcium agent adding cylinder 80, etc. are housed in a housing (not shown).

Like the conventional example, the electrolytic cell 2 is provided with two kinds of electrodes 21, 22 and an electrolytic diaphragm 20 for partitioning the two, and has inlets 25, 26 on the bottom side and discharges on the upper side. Equipped with outlets 23, 24, these outlets 23, 24
Are connected to the discharge pipes 17 and 18 via the switching valve 6. Here, the inflow port 25 and the discharge port 23 communicate with the space surrounding the one electrode 21, and the inflow port 26 and the discharge port 24.
Is communicated with the space surrounding the other electrode 22, but the inflow port 25 is made thinner than the inflow port 26, and the flow rate flowing into the electrode 21 side is 1: 3 to the flow rate flowing into the electrode 22 side. It is designed to decrease in the ratio of 1: 4. Further, the switching valve 6 allows the discharge port 24 and the discharge pipe 17 to communicate with each other, and allows the discharge port 24 and the discharge pipe 18 to communicate with each other, and the discharge port 23 and the discharge pipe 18 to communicate with each other. It is composed of an electromagnetic rotary valve or a motor type switching valve that communicates with the pipe 17.

The water purifier 3 is provided with a filter medium 31 made of activated carbon and a filter medium 32 made of a hollow fiber membrane, and one of two openings provided at the lower end of the filter medium 31 is provided in the backwash unit 4. The other is connected to the switching valve 5. The above two types of filter media 31 and 32 are contained in a single cartridge, and the cartridges can be replaced together.

The backwash unit 4 is a filter medium 3 in the water purifier 3.
It is for eliminating the clogging of 1, 32 by performing backwashing in which the purified water filtered by once passing through the water purifier 3 is back-flushed to the water purifier 3. As shown in FIG. The cylinder 41 includes a piston 41 arranged in the cylinder 40, and an interlocking pin 42 slidably engaged with the piston 41 and pulling down the valve body 43 against the spring 45 as the piston 41 descends.
A port 46 connected to the water purifier 3 and a discharge port 44 that opens when the valve body 43 descends and closes when the valve body 43 rises are provided at the upper end of the cylinder, and the space below the piston 41 in the cylinder 40 is It communicates with the port 55 of the switching valve 5 described below.

The switching valve 5 mounted below the backwash unit 4 has ports 51, 54 at both ends and three ports 52, 53, 55 at axially offset positions on the circumferential surface. By moving the built-in movable body 56 by the water pressure of the water selectively flowing in from the ports 51, 54, the ports 51, 52 shown in FIG. 4 communicate with each other, and the ports 55, 53 form the outer periphery of the movable body 56. The state in which communication is performed through the space 57 and the state in which the movable body 56 moves to the right in the figure to communicate between the ports 54 and 55 and the state in which communication is performed between the ports 52 and 53 through the outer peripheral space 57 are switched.

The port 52 is connected to the water purifier 3 and the port 53 is connected to the drain pipe 19. Further, the ports 51 and 54 are connected to a switching unit 98 provided on the faucet 99, and a flow rate adjusting valve 65 is provided between the port 51 and the switching unit 98. Constant flow valve 6 arranged between the port 52 and the water purifier 3
4 is provided in order to prevent excess water pressure from being applied to the water passage after the water purifier 3.

The piping connecting the ports 51 and 54 to the switching unit 98 is disposed inside the body of the electrolyzed water producing apparatus, as shown in FIG. And the contact portion is formed by a metal tube 72 made of copper, aluminum or the like. The water supplied to the power supply unit can be cooled to increase the safety of the power supply unit against heat generation.

The discharge port 44 of the backwash unit 4
Is connected to the inflow ports 25 and 26 of the electrolytic cell 2 by a pipe 47. A flow meter 66, a check valve 67 and a solenoid valve 63 are provided in the middle of the pipe 47.
Among the pipes that individually connect the solenoid valve 63 and the inlets 25 and 26, the calcium agent addition cylinder 80 is provided in the middle of the pipe 48 that reaches the inlet 25. The check valve 67 is connected to the drainage port 19 and is closed when water pressure is applied to the pipe 47 side, but is opened when water pressure is not applied to the pipe 47 side, and the check valve 67 inside the electrolytic cell 2 is closed. The water and the water in the pipe 47 are discharged from the drain port 19.

A pre-filter 90 and an electromagnetic three-way valve 86 are connected in the middle of the discharge pipe 18, and a pH sensor is provided in a branch path that branches from the electromagnetic three-way valve 86 and joins again on the downstream side of the discharge pipe 18. 7 are provided. As the pH sensor 7, here, as shown in FIG.
Alternatively, by adding a trace amount of a reagent consisting of NaCl to the water passing through the passage part of the above-mentioned water, the pH may be adjusted by the electric conductivity of the water at this time.
As shown in FIG. 5 (b), p
It is configured to output a voltage of 0 to 5 V according to the H value, and this output voltage is A / D converted and then taken into a control circuit C described later.

Alkaline ionized water having a pH of 10 or more,
In particular, when the carbonic acid component is excessive, such as groundwater, the abundance ratio of the carbonate ion CO ₃ ^{2− is} larger than that of the hydrogen carbonate ion HCO ₃ ⁻ , and in this case, the phenomenon of precipitation as calcium carbonate increases. If the sensing portion of the pH sensor 7 is covered by the deposition of this scale, the sensing accuracy of the pH sensor 7 (particularly on the acidic side) is lowered and the rising response is deteriorated. The pre-filter 90 is a filter having a partial charge δ ⁻ such as glass wool, and plays a role of trapping the generated CaCO ₃ having a partial charge δ ⁺ and reducing the total amount flowing into the pH sensor 7. The same effect can be obtained by using a magnetic means that generates a magnetic field perpendicular to the flow path instead of the prefilter 90. The electromagnetic three-way valve 86 also plays a role in suppressing the scale generation, which will be described later.

The electrolyzed water generator thus formed is
As described above, the two ports 5 in the switching valve 5
1, 54 are connected to the switching unit 98 via individual pipes. The switching unit 98 is configured to be able to switch between stopping water supply to the electrolyzed water generator, supplying water to the port 51 side, and supplying water to the port 54 side by operating a lever. .

Next, the flow of water at the time of taking out the electrolyzed water will be described. In the switching unit 98, if the water is made to flow to the port 51 side of the switching valve 5, the water reaching the port 51 of the switching valve 5 will be Movable body 56 in switching valve 5 by water pressure
2, the water purifier 3 enters from the port 52, is filtered by the filter media 30 and 31, and then reaches the port 46 of the backwash unit 4. Then, the water that has entered the cylinder 40 of the backwash unit 4 from the port 46 first pushes down the piston 41 by the water pressure, opens the discharge port 44 that was closed by the valve body 43 until then, and from this discharge port 44 to the pipe 47. Through the inlet 25 of the electrolytic cell 2,
It enters into the electrolytic bath 2 from 26 and is electrolyzed there. In addition,
The energization of the electrolytic cell 2 is started by the flow rate information obtained from the flow meter 66 arranged in the middle of the pipe 47.

If there is an instruction to obtain alkaline ionized water, the electrode 21 of the electrolytic cell 2 serves as the anode,
Since the electrolytic voltage is applied so that the electrode 22 serves as the cathode, acidic ionized water is obtained at the ejection port 23 side and alkaline ionized water is obtained at the ejection port 24 side. At this time, the switching valve 6 is shown in FIG. Because of the state, the alkaline ionized water is discharged to the discharge pipe 18 side and the acidic ionized water is discharged to the discharge pipe 17 side.
At this time, the electromagnetic three-way valve 86 guides the alkaline ionized water to the pH sensor 7 side for pH value feedback control. However, if the pH value becomes the target pH value and becomes stable, the pH value may change. For example, until the flow rate changes, the flow of the alkaline ionized water to the pH sensor 7 side is stopped, and it is directly sent to the discharge pipe 18. This is to reduce the state in which the scale deposits on the sensing portion of the pH sensor 7.

When it is instructed to obtain acidic ionized water, there are the following two water streams depending on the instructed acidity. First, in the case of weakly acidic ionized water, electrolyzer 2
Since the electrolytic voltage is applied so that the electrode 21 of FIG. 2 serves as a cathode and the electrode 22 serves as an anode, alkaline ionized water is obtained at the ejection port 23 side and acidic ionized water is obtained at the ejection port 24 side. Since the valve 6 is the same as in the above state, the alkaline ionized water is discharged to the discharge pipe 17 side and the acidic ionized water is discharged to the discharge pipe 18 side.

In the case of strong acidic ionized water, an electrolytic voltage is applied so that the electrode 21 of the electrolytic cell 2 serves as an anode and the electrode 22 serves as a cathode, so that the acidic ionized water is discharged to the discharge port 23 side.
Alkaline ionized water is obtained on the side of the discharge port 24. At this time, the switching valve 6 is switched to a state different from the above two states as shown in FIG.
Side, the acidic ionized water is discharged to the discharge pipe 18 side. As described above, when the strongly acidic ionized water is discharged from the discharge pipe 18 side, the electrode 21 side serves as the anode as described above.
This is because the inflow port 25 to the electrode 21 side is narrowed down from the inflow port 26 on the electrode 22 side to reduce the inflow amount, so that it is easy to obtain the strongly acidic ionized water. When discharging such acidic ionized water, the electromagnetic three-way valve 86
Always sends out acidic ionized water through the pH sensor 7. This is because the scale deposited in the pH sensor 7 is melted and discharged.

Then, in the switching unit 98, if the water is made to flow to the port 54 side of the switching valve 5, the switching valve 5 is switched by the movement of the movable body 56 by the water pressure, and the water entering from the port 54 passes through the port 55. It flows into the space below the piston 41 in the backwash unit 4, pushes up the piston 41, closes the discharge port 44 with the valve body 43, and the filtered purified water accumulated in the space above the piston 41 from the port 46 through the water purifier. Back flow to side 3. The backflow water backwashes the filter media 32 and 31 to wash away the impurities adhering to the filter media 32 and 31, and then the ports 52 of the switching valve 5
It is discharged from the drain port 19 via 53. The inflow of water from the switching unit 98 at this time ends when the piston 41 in the backwash unit 4 is moved to the top dead center. Then, during such backwashing, the switching unit 98
When the water is stopped in the water, the water in the electrolytic cell 2 passes through the check valve 67, which is in the open state because there is no water pressure difference, and then the drain port 1
Emitted from 9.

FIG. 1 is a block circuit diagram of the electrolyzed water producing apparatus, in which C is the control circuit constructed by a one-chip microcomputer, and D is an operation display section. The control circuit C, to which the pH sensor 7 and the flow meter 66 are connected, is configured so that the electrolysis voltage applied to the electrodes 21 and 22 of the electrolytic cell 2 can be controlled by PWM control, and the target pH is also set. The built-in comparison circuit C1 for comparing the pH value with the pH value of the electrolyzed water being discharged through the discharge pipe 18 obtained from the pH sensor 7 to detect the target pH value.
Feedback control of the electrolytic voltage is performed so that the values match.

FIG. 7 shows an example of the display operation unit D. As an operation unit, in addition to the power switch SW ₁ , a pH switch SW ₂ , a switch SW ₃ for instructing strong electrolysis, a switch SW ₄ for checking raw water, a switch SW ₅ for switching to acidic, and a fine pH adjustment Switch for
In addition to having W ₇ , the current time setting switch SW ₈ , switch SW ₉ for turning on and off to indicate by sound that electrolysis is in operation, and cumulative usage time of water purifier 3 accumulated in control circuit C The switch SW ₁₀ for resetting is provided.

As the display unit, a display unit La for displaying the pH value obtained by the pH sensor 7 by numbers, a display unit Lb for displaying the flow rate information obtained from the flow meter 66, a display unit Lc for displaying the current time, Switch SW ₂ , SW ₃ , SW
Display unit Ld for displaying the selected state of ₅ , Display unit Le for displaying that the electrodes 21, 22 are being washed, Display unit Lf for prompting replacement of the filter media 31, 32 of the water purifier 3, Carbon dioxide content in raw water In addition to a display unit Lg for displaying whether or not the pH is large, a display unit Lp for prompting the replenishment of the reagent of the pH sensor 7, a display unit L ₁ for indicating the power supply state, and a switch SW. ₂ , a display portion L ₂ that lights up when the discharge of alkaline ionized water is selected by SW ₃ , SW ₄ , and a display portion L that displays which of two types of acidic ionized water that can be selected by the switch SW ₅ is selected Equipped with a light emitting display such as ₃ , L ₄ .

The cleaning of the electrodes 21 and 22 is performed by cleaning the electrodes 21 and 22.
The flowmeter 66 is for removing the scale generated in the
When the water stop is detected by the
By applying a voltage having a polarity opposite to that used for a short time, the electromagnetic valve 63 is closed at the start of this cleaning, and therefore the reverse electromotive cleaning is performed in the water retention system.
At this time, the pH value on the anode side is p
Since it has a strong acidity of about H2, the adhered calcium carbonate and magnesium carbonate components can be dissolved and removed. Further, in the latter half of the reverse electrolysis cleaning, the solenoid valve 63
Since the electrode is opened, a reverse electrode cleaning in a running water system is also performed, so that complete electrode cleaning can be expected. In addition, since the cleaning water containing scale contained in the electrolytic cell 2 is discharged from the inlets 25 and 26 through the drainage port 19 at the time of this cleaning, the cleaning water is not mixed at the time of the next use start.

[0032] Thus, in that an operation display unit D as described above, and the display unit L ₁ if power on switch SW ₁ is turned on, pressing the switch SW ₂ in this state, the number of times to press the The level of “purified water” or “1 to 4” can be selected accordingly, and the selected state is displayed on the display unit Ld, and the switching unit 98
If you send water through, the selected action will be performed.
When “purified water” is selected, the “purified water” portion of the display section Ld is lit and displayed, and since the electrolysis voltage is not applied to the electrolytic cell 2, the water purifier 3 is supplied from the discharge pipe 18. The purified water is discharged, and the flow rate and pH value of the water at this time are displayed on the display portions La and Lb.

When any of the levels 1 to 4 is selected, the flow meter 66 senses the water flow and starts the application of the electrolytic voltage. At this time, the control circuit C discharges from the pH sensor 7. Feedback control of the electrolysis voltage is performed so that the pH value of the electrolyzed water discharged from the pipe 18 becomes a target pH value preset according to the selected level. The target pH value is, for example, at level 1
9.0, level 2 at pH 9.5, level 3 at pH 10.
A value such as pH 10.5 is set to 0 and level 4. The detected pH value is displayed numerically on the display unit La, and the flow rate detected by the flow meter 66 is displayed on the display unit Lb.

Incidentally, the alkaline ionized water having a pH of 9.0 to 9.5 obtained at Level 1 and Level 2 allows stable storage of Ca ions both in calculation and measurement, and has a pH value higher than that. In the case of water, if the amount of hydrogen carbonate ions in the raw water is excessive, the precipitation phenomenon of calcium carbonate will occur, and it will be impossible to maintain the Ca ion standard concentration desired for alkaline ionized water after standing for 1 to 2 days.

When strong electrolysis is indicated by the switch SW ₃ , strong electrolysis is indicated on the display portion Ld and, for example, 11 is set as the target pH value, and the pH value detected by the pH sensor 7 becomes this value. Thus, feedback control of the electrolytic voltage is performed. Switch SW
₄ is that when this is pressed, a predetermined voltage of about 20 to 25 V is applied to the electrodes 21 and 22 for a predetermined time, and
PH of electrolyzed water at a certain time after the start of electrolysis
When the pH value is detected by the pH sensor 7 and the pH value of the electrolyzed water at this time is 8.5 to 9.5 or less without reaching a predetermined value of about 9.5 to 10.5, the display unit Lg displays The user is informed that the water purified through the water purifier 3 by lighting up contains a large amount of carbon dioxide (CO ₂ ). The water quality is checked for its adaptability to electrolysis of raw water, and by displaying this result, the user can know the water quality.

Even in the normal alkaline ionized water discharge mode, p of the electrolyzed water after a predetermined time has elapsed from the start of electrolysis
If the H value does not reach the target pH value, the display portion Lg is lighted up. At this time, the user receives the above display and throttles the flow rate adjusting valve 65 to flow into the electrolytic cell 2. If the flow rate is reduced, the flow velocity passing between the electrodes 21 and 22 becomes slower, so that electrolyzed water having a pH value that matches the target pH value can be obtained. Of course, such reduction of the flow rate is effective when it is desired to obtain alkaline ionized water having a pH value of 10 or more.

[0037] Pressing the switch SW _5, a display unit L ₃ to indicate that the selection of the weakly ionized water that can be used by the number of times the pressing As astringents water is made, the selection of strong acid ion water is made The display section L ₄ for indicating that is turned on alternately, and the target pH value according to the selected electrolytic strength is set. Here, the target pH value is set to 5.8 for weakly acidic ionized water, and the target pH value is set to 3 to 2 for strongly acidic ionized water.
Feedback control of the electrolytic voltage is performed so that the target pH value acidic ionized water is discharged to the discharge pipe 18.

The flow path for weakly acidic ionized water is shown in FIG.
As described above, the flow path in the case of strongly acidic ionized water is as shown in FIG. 3 as described above. By switching the flow in this manner, that is, the strongly acidic ionized water is obtained. The strongly acidic ionized water is easily obtained by reducing the flow rate flowing to the electrode 21 side.

Next, the details of the feedback control will be described. Here, the feedback control is performed based on the following algorithm. That is, the target pH value is p
Assuming HO , the measured pH is as shown in Fig. 8 (a).
An arbitrary voltage (for example, maximum voltage) is applied until the value changes by ± 0.4 pH, and the time required for the pH value to change by a predetermined value (for example, 0.2 pH) is counted during this period. From this value, the pH value after unit time (pH
A), the voltage ΔV corresponding to ΔpH = pHA−pHO from the voltage-pH characteristic table as shown in FIG. 8B.
However, the voltage is changed from the voltage up to that point and this voltage is applied.
In this way, the count of the time required for the pH to change by a predetermined value and the prediction of the pH value after a unit time based on this count, and the application of the voltage based on the above prediction obtained from the voltage-pH characteristic table are calculated as ΔpH value. Is repeated every unit time until the pH becomes within ± 0.1 pH, and if it falls within the above range, the voltage at that time is maintained.

However, when the target pH values are different, that is, when alkaline ionized water is desired, weakly acidic ionized water is desired, and strongly acidic ionized water is desired, side reactions during electrolysis are performed. Since there is a difference in reaction time due to different (for example, chlorine ion oxidation reaction),
A voltage-pH characteristic table (curve a shown in FIG. 8 (b)) suitable for each target pH value (here, for each generation mode of alkaline ionized water, weakly acidic ionized water, and strongly acidic ionized water),
(B) and (c) are prepared and feedback control is performed using the corresponding ones. Note that these voltage-pH characteristic tables can be represented by an approximate expression of pHv = A + Blog _e V (A and B are constants that differ for each mode).

Examples of changes in pH value when feedback control is performed in this manner are shown in FIGS. Figure 9 shows pH
This is a case where the target pH value is set to 9.8 for water of No. 7, and FIG. 10 shows a case where there is a disturbance during the discharge of alkaline ionized water having a target pH of 9.8. When a change of 0.2 pH is detected, the corresponding control is started. FIG. 11 shows a case where the target pH is switched from 10.5 to 9.8. In this case, in order to see the pH change, a low electrolysis voltage is applied as an arbitrary voltage for a predetermined time at the time of switching to 9.8.

[0042]

As described above, in the present invention, the target p
Feedback control is performed by applying a voltage based on the voltage-pH characteristics set according to the H value, and
The control circuit has a voltage-pH characteristic set according to the target pH value.
The voltage application based on the
And predicting the pH value after a predetermined time from
The voltage difference ΔV corresponding to the difference ΔpH from the standard pH value is the above voltage.
-Derived from the pH characteristics, subtract the voltage difference ΔV from the current voltage
Since the applied voltage is the next applied voltage, the control suitable for the rising characteristic of the pH value with respect to the voltage change of the target pH value is performed.
The value can be converged to the target pH value at an early stage, and the electrolyzed water having the desired pH value can be reliably and quickly obtained.

At this time, the control circuit keeps applying the voltage based on the voltage-pH characteristic set according to the target pH value for a certain period of time, and predicts the pH value after a predetermined period of time from the pH change during this period.
Then , if the next voltage is applied based on the difference between the predicted pH value and the target pH value, the feedback control can be easily performed. The target pH value is 9.0 to 9.
If the electrolytic water generation mode 5 is provided, the calcium ion concentration can be stabilized during long-term storage.

In addition, in the electrolyzed water inflow part to the pH sensor,
A valve that switches the electrolyzed water flow path is installed in the bypass path that bypasses the pH sensor when alkaline ionized water is generated and
When the pH value detected by the pH sensor reaches the target pH value
When the pH value detected together is stable , the electrolyzed water flow path is switched to the bypass path, and the pH is constantly adjusted when acidic ionized water is generated.
If electrolyzed water is allowed to flow to the sensor side, it is possible to suppress the deposition of scale on the pH sensor and to remove the deposited scale. the electrolytic water inflow to the pH sensor, the partial charges of glass wool [delta] ^- Yu
It is possible to suppress the deposition of scale on the pH sensor by disposing a pre-filter for the purpose or by disposing an electromagnetic means for applying a magnetic field perpendicular to the flow channel.

By disposing the metal pipe part in the water channel below the power supply part and thermally connecting the power supply part and the metal pipe part with a heat radiating plate, it is possible to obtain an overcurrent. The safety can be increased against excessive heat generation. Further, a discharge passage for discharging water in the electrolytic cell and a valve for closing the discharge passage are provided, and the control circuit is provided with a reverse electrolysis cleaning mode in which the voltage applied to the electrolysis cell has a reverse polarity to perform the reverse electrolysis cleaning. At this time, by switching between the closed mode and the open mode of the valve during the reverse polarity voltage application time, the reverse electrolysis cleaning of the electrolytic cell can be performed more effectively.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of an embodiment.

[Fig. 2] Fig. 2 is a schematic diagram showing the same as above when ejecting alkaline ionized water or weakly acidic ionized water.

[Fig. 3] Fig. 3 is a schematic diagram showing the same acid ionized water as above being discharged.

FIG. 4 is a cross-sectional view of the above backwash unit and a switching valve.

5A and 5B show the pH sensor of the above, wherein FIG. 5A is a schematic sectional view and FIG. 5B is an output characteristic diagram.

6A and 6B show a cooling structure of the power supply unit of the above, wherein FIG. 6A is a perspective view and FIG. 6B is a sectional view.

FIG. 7 is a front view of the display operation unit of the above.

FIG. 8 shows an algorithm of feedback control in the same as above, (a) is an operation explanatory diagram, and (b) is a voltage-pH characteristic diagram.

FIG. 9 is a flowchart showing an example of control.

FIG. 10 is a flowchart showing another example of control.

FIG. 11 is a flowchart showing another example of control.

FIG. 12 is a schematic sectional view of a conventional example.

[Explanation of symbols]

C control circuit 2 electrolysis tank 7 pH sensor

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hiroyuki Noguchi, 1048, Kadoma, Kadoma, Osaka Prefecture, Matsushita Electric Works, Ltd. (72) Toichi, Nishikawa, 1048, Kadoma, Kadoma, Osaka, Matsushita Electric Works, Ltd. (56) Reference: JP-A-5-64785 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C02F 1/46

Claims (7)

(57) [Claims] 1. An electrolytic cell for producing alkaline ionized water and acidic ionized water by electrolysis to separately discharge the electrolyzed water, a pH sensor for continuously measuring the pH value of the electrolyzed water, and this pH sensor. In the electrolyzed water production apparatus provided with a control circuit for performing feedback control of the electrolysis voltage applied to the electrolytic cell by comparing the pH value obtained from the target pH value with the target pH value, the control circuit sets the voltage set according to the target pH value. -P
Feedback control is performed by applying a voltage based on the H characteristic, and the control circuit responds to the target pH value.
Applying voltage based on the set voltage-pH characteristics for a certain period of time
The pH value is maintained and the pH value after a predetermined time is predicted from the pH change during this period.
In consideration, the difference between the predicted pH value and the target pH value is equivalent to ΔpH.
The voltage difference ΔV of the current voltage is calculated from the above voltage-pH characteristic to obtain the current voltage.
The electrolyzed water producing apparatus is characterized in that a voltage obtained by subtracting the voltage difference ΔV from the above is used as the next applied voltage . 2. The electrolyzed water production apparatus according to claim 1, further comprising an electrolyzed water production mode having a target pH value of 9.0 to 9.5. 3. The pH is provided at the electrolyzed water inflow portion of the pH sensor.
A valve that switches the electrolyzed water flow path is installed in the bypass path that bypasses the sensor, and the control circuit controls the pH detected when the alkaline ionized water is produced and by the pH sensor.
The electrolytic water flow path is switched to the bypass path when the detected pH value becomes stable with the value becoming the target pH value, and the electrolytic water flow path is always provided on the pH sensor side when acidic ionized water is generated. 1. The electrolyzed water generator according to 1. 4. The electrolyzed water generating apparatus according to claim 1, wherein a pre-filter having a partial charge δ ⁻ of glass wool or the like is arranged in the electrolyzed water inflow portion to the pH sensor. 5. The electrolyzed water producing apparatus according to claim 1, wherein a magnetic means for applying a magnetic field perpendicular to the flow path is provided at an electrolyzed water inflow portion to the pH sensor. 6. A metal pipe part in a water channel is disposed below a power supply part composed of a switching power supply, and the power supply part and the metal pipe part are thermally connected by a heat radiating plate. The electrolyzed water producing apparatus according to claim 1, which is characterized in that. 7. A drainage channel for draining water in the electrolytic cell and a valve for closing the drainage channel are provided, and the control circuit has a reverse electrolysis cleaning mode in which the voltage applied to the electrolytic cell has a reverse polarity, 2. The electrolyzed water producing apparatus according to claim 1, wherein the control circuit switches between the closed mode and the open mode of the valve during the reverse polarity voltage application time during the reverse electrolysis cleaning.