CA2078749A1

CA2078749A1 - Controlling apparatus for continuous electrolytic ion water producing apparatus

Info

Publication number: CA2078749A1
Application number: CA002078749A
Authority: CA
Inventors: Kazuyoshi Arai
Original assignee: Kazuyoshi Arai; Janix Kabushiki Kaisha; Miz Co., Ltd.
Current assignee: Miz Co Ltd
Priority date: 1991-10-09
Filing date: 1992-09-21
Publication date: 1993-04-10
Also published as: KR0140378B1; EP0537528A1; JP3149138B2; KR930007818A; JPH0596280A; US5316646A

Abstract

ABSTRACT OF THE DISCLOSURE
A controlling apparatus which can control a continuous electrolytic ion water producing apparatus so that determination and indication of energization and an electrolyzing capacity of an electrolytic cell and determination and indication of a life of a filter cartridge are performed appropriately. A control unit connected to a power source circuit of the electrolytic cell includes electrolysis judging means which judges it from a signal of a flow rate sensor and a signal of a range change-over switch whether or not an electrolyzing operation should be performed. When the electrolyzing judging means judges that an electrolyzing operation should be performed, a power source switch is turned on to cause the power source circuit to energize the electrolytic cell to perform an electrolyzing operation.
On the contrary when it is judged that an electrolyzing operation should not be performed, the electrolysis judging means turns off the power source switch to put the electrolytic cell into a deenergized condition.

Description

~?~ .9 TITLE OF TIIE INVENTION
Controlling Apparatus for Continuous Electroly-tic Ion ~ater Producing Apparatus C~CKGROUND OF TIIE INVENTION
1. Fleld of the Invention Thls invention relates to a con-tinuous electrolytic ion water producing apparatus which electrolyzes water such as ci-ty water to continuously produce alkall ion water and acid ion water. and more particularly to a controlling apparatus for a continuous electrolytic ion water producing apparatus oi' the type mentioned which performs determination and indication of energization and an electrolyzing capacity of an electrolytic cell, determination and indication of a life of a filter cartridge provlded for removing residual chlorine.from water and so forth.

2. Description of the Related Art A continuous electroly-tic ion water producing apparatus which applies a dc volta~e between a pair of positive and negative clectrodes in drinking water such as city water -to electrolyze the drinking water to directly produce alkali ion water and acid ion water is already known as one of producing apparatus for ,: . : ~ :............. . . ..... ... ... .. . .

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" ., producing a medical substance. Alkali ion water is used to improve the acid physical constitu-tion arising from cating habits oP moderns prlnclpally dependlng upon meat to promote the health whlle acld ion water ~s used to wnsh thc surface of a hllmarl body and so forth for makc-up.
A conventional electrolytlc ion water produclngapparatus of the -type mentloned is generally constructed such that, when water flows therethrough, it ls detected uslng a pressure switch whether or not water flows at more than a predetermined reference flow rate, and when water flows at more than the reference flow rate, an electrolytic cell is energized automatically to produce ion water. The electrolyzing capacity of the electrolytic cell increases as the flow rate decreases, and besides the hydrogen ion exponent tp~l) of electrolytic lon wa-ter produced depends much upon the flow rata and so forth. Therefore, a ran8e change-over swltch for changing over the electrolyzing strength is provlded such that a user operates, visually estimating a flow rate of lon water -flowlng into a glass, the range change-over switch to regulate the electrolyzing capaclty. ~urther, while a filter cartridge for removlng resldual chlorlne contalned in city water ls , .. . ,.. ., , , ., at-tached to an inle-t pipe, the time of exchange of the filter cartridge from the expiration of its life is normally determined from a cumulative water passlng time of the filter cartridge.
~ lth the conventional electrolytlc ion water producing apparatus, however, a pressure switch is employed to detect a flow of wa-ter, and the pressure switch does not sometimes operate regularly in a region in which the pressure of city water is comparatively low or when a pipe line is partially damaged. Particularly in case the outlet por-t for ion water is choked, the electrolytlc cell may be enerKized in error whlle water does not flow. Meanwhile, as regards regularizatlon of the electrolyzing capaclty, since measurement of the flow rate relles upon the sixth sense of a user, changing over of the ran8e of the electrolyzing strength cannot be performed accurately, and when the quality of water changes and the change of the quality of water has .:
an influence on -the electrolyzing capacity, it is almost impossible to regularize the electrolyzing capacity.
Further, since the determination of a life of the filter cartridge depends upon the cumulative water passing time therethrough, a grea-t difference may be caused between the cumula-tive quantity of water actually used and the : - ; . ; ~ ... . , l : .. -, " ~ ~ ;; ~ .:.,. : :,. ,;;
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capacity of -the filter -from the difference in degree of water flow among various homes, that is, from the dlfference in flow rate per unit tlme. Consequently, it is not posslble to determlne the life accurately in any caso. Accordlngly, lt Is demanded to eFFectlvely solve the problems of the conventional electrolytic ion water producing apparatus described above.
A solution to -the problems is disclosed, for example, in Japanese U-tility Model Laid-Open Applicatlon No. 1-163494. According to the proposed solutlon, an electrolytic current supplied to an electrolytlc cell ls detected, and the magnitude of the electrolytic current is controlled so as to coincide with a value of a current set by selec-tive operation of an electrolyzing strength adjustin6~ swi-tch.
With the proposed solution, however, slnce an electrolytic current is controlled in response to selection of the electrolyzing strength adjusting switch, such control is not available as to regularlze the electrolyzing capaci-ty in various conditions of use or to precisely determine and indicate a life of a filter cartridge.

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SUMMA~Y OF TIIE INVENTIO~
It is an object of -the present invention to provlde a controlllng apparatus which can control a contlnuous electroly-tlc lon water producing apparatus so that dotormlnatlon and lndlcatlon of energlzatlon and an electrolyzing capacity of an electrolytic cell and determina-tion and lndication of a llfe of a fllter car-tridge are performed appropriately.
In order to a-t-tain the object, according to the present invention, there ls provlded a controlling appara-tus for a continuous electrolytic ion water producing apparatus which includes an electrolytic cell, a pair of negative and positive electrodes accommoda-ted in the electrolytic cell and a water pipe line for introducing water to the electrolytic cell, which comprises a filter cartridge disposed in the water pipe .
line for removing residual chlorine in water passing through the water pipe line, a flow rate sensor disposed in the water pipe line for detecting a flow rate of wa-ter passing through the water pipe line, a power source circuit for applying a dc voltage between the negative and posi-tive electrodes, a range change-over swltch for adJusting the electrolyzing strength of the electrolytic cell, a power source switch for the power . . , - . , . :

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source circuit, and a control unit for judging whether or not an electrolyzlng operation should be performed in response to a flow rate detected by the flow rate sensor and an 01ectrolyzing strength o-f the electrolytlc cell, which Is determln~d by an opera-ted posltlon of the ranBe change-over swi-tch, and controlling the power source switch in accordance with the judgment~
In -the controlling appara-tus for a continuous electrolytic lon wa-ter producing apparatus, when water actually flows through the electrolytlc cell, res~dual chlorine in the water is removed by the -fllter cartridge, and a flow rate is de-tected from a signal of -the flow ra-te sensor. Thus, when a -flow rate is detec-ted from a signal. of -the flow rate sensor and the range change-over switch is at i-ts electrolyzing position, the power source switch is turned on by the control unit so tha-t the elec-trolytic cell is energized by the power source circuit to perform an electrolyzing operation regularly. On the other hand, when no water flows and no flow rate is detected from a signal of the flow rate sensor, or when the range change-over switch is at its no-electrolyzing position even i-f a -flow ra-te is detected from a signal of the flow rate sensor, the power source switch is turned off by the control unit~

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Consequently, the electroly-tic cell ls thereafter kept in a deenergizecl condition. Thus, the electrolytic cell can bc energlzed precisely without beinB lnfluenced by a pressure of water or partial damage to a water plpe 1 Ino.
Preferably, the control unit includes wa-ter passage amount calcula-ting means for accumulating a flow ra-te to calculate a cumulative water passage amount when .: --water flows through the water pipe line, and filter life Judging mcans for j~ldging the life of the filter cartridge from the accumulated water passage amount and indicatlng, when it is detected that the life of the filter cartridge has expired, such expiration of the life. Thus, the filter of the filter cartridge can be exchanged suitably in accordance with the capaclty of the filter. In this instance, preferably, the filter ~ -cartridge includes a reset switch which resets accumulatlon of the water passage amount by the water passage amount calculating means when a filter thereof .
ls exchanged. An error in determination of the life of the filter can thus be prevented effectively.
Preferably, the con-trol unit includes electrolyzing capacity judging means for judging, when water flows through the water pipe line, an ,, ' ' 2~

electrolyzing capaci-ty from a flow rate detected by -the flow rate sensor and incllcating whe-ther the flow rate is excessively high, cxcesslvely low or appropriate. Thus, the electrolyzlng capacity of the electrolytic cell with re~pect to a flow rate can be Jud~ed accuratcly and hence optlmlzed, and accordlngly, the rellabili-ty o-f acid or alkali ion water obtained is enhanced. Further, also when the quality of water is dlfferent, the electrolyzing capaclty of the electrolytic cell can be corrected approprlately taklng the judgment of the electrolyzlng capaclty into consideratlon.
The above and other objects, features and advantages of the present invention will become apparent from the following description and the appended clalms, -taken in conjunction with the accompanying drawings in which like parts or elements are denoted by like , reference charact~rs.

BRIEF DESCRIPTION OF TIIE DRAWINGS
Fig. 1 is a circuit diagram schematically showing a water flow route and a power source circuit of a continuous electrolytic ion producing apparatus in which a controlling apparatus according to the present invention is incorporated:

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Eig. 2 ls a schematic circuit diagram bf an electric control system for the continuous electrolytic ion water producing apparatus shown in ~ig. 1: and Fi~. 3 is a block diagram of the controlling circuit of the controlling system shown in Flg. 2.

DETAILED DESCRIPTION OF T~IE PREEERRED EMBODIMENT
Referring first to Fig. 1, there is shown a continuous electroly-tic ion water producing apparatus in which a controlling apparatus according to the present inven-tion is incorporated. The continuous electrolytic ion water producing appara-tus shown includes an lnlet pipe 1 serving as a water pipe adapted to be connected to a city water pipe or the like to introduce city water into the continuous electrolytic ion water produclng apparatus therethrough. The inlet pipe 1 communicates with a filter cartridge 2 for removing residual chlorine in city water introduced thereto. An outlet pipe 3 of the filter cartridge 2 communicates with an electrolytic ccll 5 by way oF a rlow rate sensor ~ of the rotary -type lnterposed between them. The electrolytic cell 5 is of the enclosed -type, and the exit side of the inside thereof is parti-tioned by a partition or the like into two sections in which a negative electrode 6 and a ,, ,: , ,~ . . . ,, :. . ,-~, . .
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r ~3 positive electrode 7 are disposed separately. An outlet pipe 8 for alkali ion water is connected to the electrolytic cell 5 adJacent the negative electrode 6 whlle another ou~let pipe 9 for acld lon water ls connoc to~ to ~ho eloctrolytlc cell 5 a~J acent the posltlve electrode 7 so that alkall lon water and acld lon water can be extracted separately from the output pipes 8 and 9, respectively.
A power source circuit 10 is provlded for the 0lectrolytic cell 5 and includes an ac power source 11 connected -to the primary winding of a power source transformer 12, a secondary winding of which is connec-ted to a rectlfyln~ clrcuit 1~ by way of a blmetal thermostat 13 for the prevention of overheatlng. The positive and nega-tive poles of the dc voltage output side of the rectifying circuit 1~ are connected by way ~.
of a smoothing capacitor 15 to a swltching regulator 16 of the pulse width modulating type (PWM) for controlling :;
a dc power supply. The outputs of the switching regulator 16 are connec-ted individually to the posltive electrode 7 and the negative electrode 6 by way of a power source switch 17 and a polarity reversing switch 18. Meanwhile, in order to obtain a controlling power, another secondary winding of the power source ., ,~ : , : :

~f"` ~ ? ~3 transformer 12 is connected by way of another rectifying circuit 19 and another smoothing capacitor 20 to a constant vol-tage circu~t 21, which ls connected to a control unlt ~0 so that a flxed voltage may be supplled to the control unlt ~0.
Referring now to Fi~. 2, there is shown an elec-tric control system for -the continuous electrolytic ion water producing apparatus shown in Fig. l.
~eferring also to Fig. 1, a current sensor 22 for detecting an elec-trolytlc current is provlded at the secondary winding of the power source transformer 12 connected to the rec-tifying circuit 14, and an output slgnal of the curren-t sensor 22 ls lnputted to the control unlt ~0. A reset switch 23 is provided for the filter cartrldge 2 and resets upon exchanglng of a filter, and a swltch signal of the reset switch 23 ls lnputted to the con-trol unit 40. The flow ra-te sensor 4 detects rotation o-f an electromagnetic vane wheel 4a dlsposed in the water pipe line by means of a Hall effect element 4b and outputs corresponding pulses. The pulse signal ls lnputted to the control unit 40 by way of a waveform shaping circuit 24. The control unit 40 counts pulses of the pulse signai from the flow rate sensor 4 to detect a flow rate of water, and the power ,- , ;. :: ; - -:

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source switch 17 is switched on and of f by means of a relay 25 in response to the flow rate thus detected.
Further, af-tor stopping of flowlng of water, a scale removlng time is set in response to -the water passlng nmount, ~nd tho polarlty rovorslng swltch 18 Is changod over to the opposltely connecting posltlon by means of another relay 26 in accordance wlth the scale removing time thus sen-t to automatlcally remove scale from the positive and negative electrodes 7 and 6~
~urther connected to the control unit ~0 are an ~ -acid-alkali change-over switch 27 which is to be operated when one of acid ion water and alkali ion water is to be used, a range change-over switch 28 for adjusting the electrolyzing s-treng-th, and a melody switch 29 which is manually operated when acid ion water ls -to be used. The electric control system further includes, as indicating means in the form of LEDs (light emlttlng diodes), a flow rate indicator 30, a range indlcator 31, an acld/alkali indicator 32, an electrode cleanlng indicator 33 which indicates that scale should be removed, a filter life indicator 3~, a melody lndicator 35 which gives a warning to inhibit drinking of water when acld ion water ls to be used. and a trouble indicator 36 which indicates that the power ~ , . . . . ... . . . . .

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source transformer 12 overheats, all connected to the con-trol unit ~0.
ReFerring now to ~ig. 3, there is shown a controlllng clrcult of -the electric control system shown In ~Ig. 2. 1`he control unlt ~0 lncludes flow rate detectln8 means ~1 for receiving a pulse signal from the flow rate sensor ~. The flow rate detectlng means ~1 detects a flow ra-te q and outputs the flow rate q as a corresponding number of pulses to electrolysis judging means ~2. 'I'he electrolysls ~ud~lng means ~2 compares the thus received flow rate q wlth a preset reference flow rate and outputs, when the flow rate q is lower than -the reference flow ra-te, an off signal to the relay clrcult 25 by way of a driving circuit ~3, but when the :.
ran8e change-over switch 28 i9 at its electrolyzing position and the flow rate q ls equal to or hiBher than the reference flow rate, the electrolysis judging means ~2 outputs an on signal. The pulse number of the flow rate q ls inputted -to elec-trolyzing capacity Judging means ~, at which an electrolyzing capaclty is Judged ln accordance with a magnltude of the flow rate q upon ' passage of water. In particular, when the flow rate q is equal to or higher than a flrst preset value, a lighting si8nal is outputted to a hiBh flow rate ,:, : ; ,::, , , . ;

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indicator 30a of the flow rate indicator 30 by way of a indica-tor circuit ~5, but when the flow rate q is equal to or lower than a second preset value, a llghting signal is outputted to a low flow rate indicator 30b of the flow rate indlcator 30. On the other hand, when the flow rate q is between the two preset values, it ls judged that the electrolyzing capacity is appropriate, and a li8hting signal is outpu-t-ted to a flow rate indicator 30c.
Further, the signals of the flow rate q, range change-over switch 28 and reset switch 23 are inputted to water passage amount calculating means 46, at which the flow rate q is accumulated, for a period of tlme until a rest signal is inputted thereto in both of ths electrolyzing and non-electrolyzing ranges, to calculate a cumulative water passage amount Q. The cumulatlve water passage amount Q is inputted to filter life judging means 47. which outputs, when the water passage amount Q comes to a certain value near a preset value therefor, a blinking signal to the filter life lndicator 34 by way of the indicator circuit 45. But, when the cumula-tive water passage amount Q exceeds the preset value and the expiratlon of the life of the filter is thus determined, a lighting slgnal is outputted to the . j . : . ~ . . :

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filter life indicator 3~.
In operation, city water is normally introduced into the electrolytic cell 5 by way of the inlet pipe l.
A fixed voltage ls supplled to the control unit ~0 from the constant volta~e clrcult 21 connected to the rectlrylng clrcult 19 on the secondary windlng sld~ of -the power source transformer 12 so that the control unit ~0 can execute its controlling operation. Thus, when neither of alkali ion water and acid ion water ls to be ~.
used, no pulse signal is lnputted from the flow rate sensor ~ to the control unit ~0. Consequently, the electrolysis Judglng means ~2 judges a rest of electrolyzing operation and outputs an off signal to the relay 25. Consequently, the power swltch 17 is turned .
off by the relay 25 thereby to deenergize the electrolytlc cell 5 so that the non-electrolyzing condition is thereafter kept.
Then, when water is allowed to pass through the --continuous electrolytic ion water produclng apparatus, city water passes through the filter cartridge 2, by which residual chlorine of the city water is removed, and the city water then flows lnto the electrolytic cell 5. Thereupon, a pulse signal from ~he flow rate sensor ~ is input-ted to the flow rate detecting meanq ~1 of the . , . , , :, -. .

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control unit ~0, at which a flow rate q is detected.
Then, in case the range change-over switch 28 is at its non-electrolyzing positlon, a non-electrolyzlng operatlon is determlncd by the electrolytlc Judging mouns ~2 ~lmllarly as doscrlbed above. Consoquently, the electrolytlc cell 5 remains ln the non-electrolyzlng condition. Accordingly, in this instance, the city water, from which chlorlne has been removed, is obtalned from the con-tinuous electrolytic ion water producing apparatus.
During such non-electrolyzing operation and during electrolyzing operation which will be hereinafter described, the flow rate q ls accumulated by the water passage amount calculatlng means 46 to calculate a cumulative water passage amount ~, and whether or not the life of -the fil-ter has expired is Judged precisely based on the cumulative water passage amount Q by the fil-ter life Judging means ~7. Then, when the expiration of the life of the filter is determined, the indicator 3~ therefor first blinks and then ls lit to indicate the expiration of the life of the filter, that is, the exchanging time of -the filter. Consequently. the user can sultably exchange the filter cartridge 2. Then, when a new fllter cartrldge 2 ls set ln posltlon, the . , . . , . ., , : ::. .: : .
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reset swi-tch 23 is operated by the filter cartridge 2 so that a reset signal is inputted to the water passage amount calculating means ~6. Consequently, the cumulative water passage amount ~ ls thereafter accumulatod b~glnnlrlg wlth zoro agaln by the water passage amount calculating means ~6.
On the other hand, if, upon passage of water, the range chan8e-over swi-tch 28 is manually operated to a predetermined electrolyzing strength range position, an electrolyzing operation is determined by the electrolysis Judging means 42, and an on signal is outputted to the relay 25 so that the power source swltch 17 is swltched on by the relay 25. Consequently, the trans~ormed voltage on the secondary winding slde of the power source transformer 12 is converted into a dc voltage by the rectifying circuit 14, smoothed by the smoothing capacitor 15 and input-ted to the switching regula-tor 16. In this instance, the control unit 40 sets a pulse wid-th in response to the operated position of the range change-over switch 28, and a pulse slgnal having the pulse width is outputted to the swltchlng regulator 16. Consequently, the switchlng regulator 16 operates to switch on and off to variably control the dc ~, supply voltage, whereby an electrolyzing voltage .
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corresponding to the operated position of the range change-over switch 28 is ou-tputted from the swi-tching regulator 16. Thus, the predetermined electrolyzlng voltage ls applled between the positlve and negatlve olectrodes 7 an~ G Or the elec~rolytlc cell 5 by way of the power source switch 17 and the polarlty reversing ~witch 18 in its regularly connecting position so that city water of the electrolytic cell 5 is electrolyzed at an electrolyzing strength corresponding to the electrolyzing voltage. Thus, if the polarity on the electrode side ls changed over by the polarity reverslng switch 18 to the outlet plpe 8 on the negatlve electrode 6 slde, then alkali ion water contain.ing a comparatlvely great amount of negative ions therein is obtained, but on the contrary i-f the polarity is changed over to the outlet pipe 9 on the positive electrode 7 side, then : .
acid ion water containing a comparatively great amount of posltive ions tharein ls obtalned.
During such electrolyzlng operation, an electrolyzlng capaclty is Judged ln accordance wlth a magnitude of the flow rate q by the electrolyzlng capaclty judging means 44, and when the flow rate q is excessively hi6h. excessively low or appropriate, the indicator 30a, 30b or 30c is lit for the individual ., .. .. ~ . .- , , ,, : :, . , ., : ........................ .

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indication in response to a lighting signal. Thus, the flow rate q will be adjusted in accordance wlth the thus lit condition of the indicator 30a, 30b or 30c observed by the ~Iser so tha-t appropriately electrolyzed acld or all(tlll lon wator ci~n always l)o obttllned~ On the othcr hand, when the quality of water ls different, the elec-trolyzlng strength range or the flow rate q may be ' adJusted, taking the indication into consideration, to compensate for the difference of the quality of water to optlmize the electrolyzing capacity. It is to be noted that acld ion water or alkali ion water obtained then and the range change-over condition are individually indicated, and a melody indication ls provided, when acid ion water ls obtained, to glve a warnln~ not to drink the water.
~ laving now fully described the invention, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto wi-thout departing from the spirit and scope of the `
invention as se-t for-th herein.

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Claims

1. A controlling apparatus for a continuous electrolytic ion water producing apparatus which includes an electrolytic cell, a pair of negative and positive electrodes accommodated in said electrolytic cell and a water pipe line for introducing water to said electrolytic cell, comprising:
a filter cartridge disposed in said water pipe line for removing residual chlorine in water passing through said water pipe line;
a flow rate sensor disposed in said water pipe line for detecting a flow rate of water passing through said water pipe line;
a power source circuit for applying a dc voltage between said negative and positive electrodes;
a range change-over switch for adjusting the electrolyzing strength of said electrolytic cell;
a power source switch for said power source circuit; and a control unit for judging whether or not an electrolyzing operation should be performed in response to a flow rate detected by said flow rate sensor and an electrolyzing strength of said electrolytic cell, which is determined by an operated position of said range change-over switch, and controlling said power source switch in accordance with the judgment.

2. A controlling apparatus for a continuous electrolytic ion water producing apparatus according to claim 1, wherein said control unit includes water passage amount calculating means for accumulating a flow rate to calculate a cumulative water passage amount when water flows through said water pipe line, and filter life judging means for Judging the life of said filter cartridge from the accumulated water passage amount and indicating, when it is detected that the life of the said filter cartridge has expired, such expiration of the life.

3. A controlling apparatus for a continuous electrolytic ion water producing apparatus according to claim 1. wherein said control unit includes electrolyzing capacity judging means for judging, when water flows through said water pipe line, an electrolyzing capacity from a flow rate detected by said flow rate sensor and indicating whether the flow rate is excessively high, excessively low or appropriate.

4. A controlling apparatus for a continuous electrolytic ion water producing apparatus according to claim 2, wherein said filter cartridge includes a reset switch which resets accumulation of the water passage amount by said water passage amount calculating means when a filter thereof is exchanged.