KR0175882B1 - Water level sensor of water purifier - Google Patents

Abstract

The present invention relates to a water purifier that removes harmful contaminants contained in raw water, such as tap water, and performs water purification. In particular, the present invention relates to a water level detection device of a water purifier that senses the amount of purified water supplied into a water purification tank, and includes a pretreatment filter, a membrane and A water purifier having a purified water tank for storing purified water while passing through a treatment filter, the water purifier comprising: a water level sensing means for sensing a water level of the purified water tank; and a water level sensing signal detected by the water level sensing means. It is composed of control means to control the water level, and it can supply AC wave to the water level sensor and eliminate the voltage difference between both ends of the water level sensor to prevent sensor corrosion by electrolysis, and accurately detect the water level of the water purification tank to overflow There is an effect that can be prevented.

Description

Water level sensor of water purifier

1 is a perspective view showing a conventional water purifier.

2 is a conventional water level detection circuit.

Figure 3 is an exploded perspective view showing a water purifier according to an embodiment of the present invention.

4 is a rear perspective view of the water purifier according to the embodiment of the present invention.

5 is an overall control block diagram of a water purifier according to an embodiment of the present invention.

6 is a detailed block diagram of the water level sensor of the water purifier according to an embodiment of the present invention.

7 is a detailed circuit diagram of the water level sensor of the water purifier according to an embodiment of the present invention.

8 is a detailed circuit diagram of the water level sensor of the water purifier according to another embodiment of the present invention.

FIG. 9 is an output waveform diagram in each part of FIG.

FIG. 9A is a voltage waveform diagram at point a of FIG.

9b is a voltage waveform diagram at point b of FIG.

FIG. 9C is a voltage waveform diagram at point c of FIG.

9d is a voltage waveform diagram at point d in FIG.

* Explanation of symbols for main parts of the drawings

25: water supply pipe 27: pretreatment filter

29 Membrane 31 Aftertreatment Filter

35: water purification tank 37: high water level sensor

39: low water level sensor 57: water supply valve

59: pressure pump 100: DC power supply means

110: water level detection means 111: waveform generator

112: water level detection unit 113: buffer

114: rectifier 120: key input means

125 control means 130 pump driving means

135: water supply valve drive means 140: memory means

145: display means

The present invention relates to a water purifier for purifying harmful water by removing harmful contaminants contained in raw water such as tap water, and more particularly, to a water level sensing device for a water purifier for sensing the amount of purified water supplied into a water purification tank.

In general, water purifiers supply purified water by removing harmful carcinogens contained in raw water such as tap water, and according to the water purification method, natural filtration, direct filtration, ion exchange resin, and reverse osmosis. Among them, reverse osmosis type applies pressure to raw water and passes water through an artificial osmosis membrane (membrane reverse osmosis filter) to perform purified water.The heavy metals, bacteria and carcinogens contained in raw water At the same time, since pure water and dissolved oxygen can supply clean water that is passed through separation and removal, it is used for cutting-edge science industry or washing of high-precision electronic components or for medical use. Recently, it is widely used for household water purifier for drinking water.

As shown in FIG. 1, the conventional reverse osmosis type water purifier has raw water, such as tap water supplied into the water supply pipe 3 through the adapter 2 connected to the faucet 1, on the rear side of the main body 4. As shown in FIG. Various harmful organic compounds, such as chlorine, are removed while passing through the pretreatment filter 5 installed therein, and the raw water passing through the pretreatment filter 5 is controlled by a water supply valve (not shown), and the pressure pump is driven. As a result, the pressure is increased to a predetermined pressure and flows into the membrane 6.

At this time, the raw water introduced into the membrane 6 is passed through a plurality of membrane membranes (not shown) in the membrane 6 to remove various heavy metals, carcinogens, bacteria, etc. contained in the raw water, the membrane 6 The raw water passing through is passed through the post-treatment filter 7 to remove odors such as toxic gases.

While passing through the post-treatment filter 7, odors such as toxic gases are removed, and the purified water is fed into the purified water tank 9 through the water supply hole 8.

If the purified water is supplied to the purified water tank 9, whether the purified water supplied to the purified water tank 9 is the full water level (maximum amount of water to block the purified water supplied to the purified water tank) or the low water level (start to supply the purified water to the purified water tank) Water level sensor to detect

In the case where the purified water supplied to the purified water tank 9 is full water level, the purified water is blocked from being supplied into the purified water tank 9, and when the purified water supplied to the purified water tank 9 is low water level, it is always in the purified water tank 9 Allow a certain amount of integer to be stored.

In addition, the purified water stored in the purified water tank 9 is discharged through the intake port 11 in accordance with the operation of the intake lever 10 it is possible to intake.

In such a conventional water purifier, the water level detecting circuit for detecting the amount of purified water supplied to the purified water tank 9 is as shown in FIG.

As shown in FIG. 2, a DC voltage output from the power supply unit 15 is applied to the sensing electrode 16a of the water level sensor 16, and the purified water supplied to the water purification tank 9 is supplied with the water level sensor 16. When contacting the other sensing electrode of the 16b, the output voltage (potential of c point) of the level sensor 16 through the buffer 17 by the resistance of the water level sensor 16 by the water and the voltage dividing resistor R1. It is input to the input terminal A / D of the control unit 18.

Therefore, the controller 18 compares the output voltage of the water level sensor 16 inputted through the input terminal A / D with a preset reference voltage to determine whether the purified water supplied to the purified water tank 9 is full water level. Or while determining whether the low water level is controlled so that a certain amount of purified water is stored in the purified water tank (9).

By the way, in such a conventional water level detection circuit, the voltage applied to the water level sensor 16 is a direct current, and the potential at point c, which is the output voltage of the water level sensor 16, is divided by the voltage dividing resistor R1. Since it is lower than the potential of point a, which is the sensing electrode 16a of 16, a voltage difference occurs across the level sensor 16, and electrolysis occurs.

Thus, when a long time elapses, the water level sensor 16 is corroded, so that the water level of the purified water tank 9 cannot be detected, resulting in overflow of water in the purified water tank 9.

Accordingly, the present invention has been made to solve the above problems, the object of the present invention is to supply the square wave of the AC type to the water level sensor and to eliminate the voltage difference between the both ends of the water level sensor to prevent sensor corrosion by electrolysis In addition, it is to provide a water level detection device of the water purifier that can accurately detect the water level of the water purification tank to prevent the overflow.

In order to achieve the above object, the water level detection device of the water purifier according to the present invention is a water purifier having a water purification tank to store the purified water while passing through the pre-treatment filter, membrane and post-treatment filter, for detecting the water level of the water purification tank It is characterized in that the water level detection means, and the control means for controlling the water level of the purified water tank in accordance with the water level detection signal detected by the water level detection means.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in Fig. 3, reference numeral 20 denotes a main body of the water purifier, and a front end of the main body 20 is provided with an accommodating portion 21 for accommodating a water intake container such as a cup.

One end of the water supply pipe 25 is connected to the connector 23 coupled to the faucet 22 on the back side of the main body 20, and the other end of the water supply pipe 25 is connected to the connector 23 from the faucet 22. As raw water is supplied through the feed water, a pretreatment filter 27 for removing various harmful organic compounds such as chlorine is connected.

One side of the pretreatment filter 27 includes a membrane having a plurality of membrane membranes (not shown inside) to remove bacteria such as various heavy metals, carcinogens, and bacteria contained in the raw water passing through the pretreatment filter 27 ( 29) is provided, and one side of the membrane 29 is provided with a post-treatment filter 31 for removing odorous components such as toxic gas contained in the raw water passing through the membrane 29.

In addition, the upper portion of the main body 20 is detachably seated in the water purification tank 35 having a water supply hole 33 on one side so that the purified water passing through the after-treatment filter 31 is stored, the water purification tank 35 The inner back of the) is equipped with full water level and low water level sensors (37, 39) for detecting the amount of purified water stored in the water purification tank (35).

In addition, a water intake lever 43 is coupled to a front surface of the water purification tank 35 so that the water purification in the water purification tank 35 is discharged through a water intake port, which is not shown, and an upper cover 45 is provided on the upper side of the main body 20. 47 is coupled, and the rear cover 49 of the main body 20 is coupled.

On the other hand, the squirt sign 41 is a sensing electrode of the full water level and low water level sensors (37,39).

As shown in FIG. 4, an upper end side of the pretreatment filter 27, the membrane 29, and the posttreatment filter 31 may be formed of the pretreatment filter 27, the membrane 29, and the posttreatment filter 31. Reset switches 51, 53, and 55 are provided to reset the use time of each filter at the time of replacement. A water supply valve 57 is installed at a lower end of the post-treatment filter 31 to open and close the water according to the water level in the purified water tank 35, that is, the water level of the purified water tank 35. The raw water flowing through the pretreatment filter 27 into the membrane 29 at the rear end thereof has a predetermined pressure, and the raw water flowing into the membrane 29 allows water purification by reverse osmosis from the membrane 29. A pressure pump 59 for boosting the pressure of the gas to a predetermined pressure is mounted.

A block diagram for controlling the water level sensing operation of the water purifier configured as described above will be described with reference to FIGS.

As shown in Figs. 5 to 7, the DC power supply means 100 converts the commercial AC voltage supplied from an AC power supply terminal (not shown) into a predetermined DC voltage necessary for the operation of the water purifier and outputs it.

The water level detecting unit 110 detects the amount of purified water supplied to and stored in the purified water tank 35, that is, the water level of the purified water tank 35. As shown in FIG. 7, the waveform generator 111 generates an AC-type square wave, and the water level sensors 37 and 39 are configured to detect a water level that changes according to a constant supplied to the purified water tank 35. Capacitor CI and impedance to amplify the square wave voltage of the level sensor signal detected by the level sensor 112 and the level sensor 112 to maintain a constant voltage difference across the level sensors 37 and 39. It consists of an amplifier 115, a buffer 113 for driving an output stage, and a rectifier 114 for smoothing a square wave signal output from the buffer 113 to the control means 125.

The key input unit 120 is a reset switch 51, 53, 55 for inputting a key signal to clear the use time of the pretreatment filter 27, the membrane 29, and the post-treatment filter 31.

In addition, the control unit 125 receives the DC voltage output from the DC power supply unit 100 and initializes the water purifier, as well as receiving the water level detection signal sensed by the water level detecting unit 100. As a microcomputer for controlling the overall water purification operation of the control unit 125, the control means 125 has a built-in timer for counting the use time of the pretreatment filter 27, the membrane 29 and the post-treatment filter 31. The exchange time of each filter over time is stored in advance on the ROM table.

The pump driving means 130 is a control signal output from the control means 125 to supply purified water into the purified water tank 35 according to the level of the purified water tank 35 sensed by the water level detecting means 110. Receiving and controlling the pressure pump 59, and the water supply valve driving means 135 supplies raw water supplied from the faucet 22 according to the level of the purified water tank 35 sensed by the water level sensing means 110. Drive control of the water supply valve 57 receives the control signal output from the control means 125 to supply or block the supply.

In addition, the memory means 140 is a pre-processing filter 27, the membrane 29 counted by the control means 125 in accordance with the opening and closing (on / off) time of the water supply valve 57 during the water purification operation of the water purifier. Is an E-ROM (EEPROM) in which the contents of the memory are electrically erased or written to store the usage time of the post-processing filter 31.

In addition, the display means 145 receives the control signal output from the control means 125 in accordance with the total filter use time stored in the memory means 140, the pre-filter 27, the membrane 29 and the post-processing In addition to displaying the replacement time of the filter 31, the operation state of the water purifier is displayed.

In the drawing, the rectifier 114 of the water level detecting unit 110 receives a square wave signal output from the impedance amplifier 115 of the buffer 113 as shown in FIG. The operational amplifier 116 for receiving and amplifying the voltage pulse output from the capacitor (C2) for outputting a voltage pulse from the inverting terminal (-), and the diode for half-wave rectifying the amplified voltage output from the operational amplifier 116 ( D1 and D2, a resistor R2 for feeding back the half-wave rectified voltage signal by the diode D2, a load resistor R3 having one side connected to the diode D2 and grounded at the other side, and the diode It consists of the smoothing capacitor C3 which filters the ripple component contained in the voltage signal half-wave rectified by (D2).

When the waveform generated from the waveform generator 111 is a sine wave, as illustrated in FIG. 8, the rectifier 114 of the water level detecting unit 110 includes the capacitors C4 and C5 and the resistor R4. R8), diodes D3 and D4, and operational amplifiers OPA1 and OPA2 constitute a full-wave rectification circuit to smooth the square wave signals output from the impedance amplifier 115.

Hereinafter, the effect of the water level detection device of the water purifier configured as described above will be described.

First, when power is applied to the water purifier, the DC power supply unit 100 converts a commercial AC voltage supplied from an AC power supply terminal (not shown) into a predetermined DC voltage required for driving the water purifier, thereby driving each circuit and control means 125. Output to

Therefore, the control means 125 receives the DC voltage output from the DC power supply means 100 and initializes the water purifier.

At this time, the water level of the purified water tank 35 that stores the purified water, that is, the water level of the purified water tank 35 is detected by the water level detecting means 110 and outputs the detected water level data to the control means 125.

Referring to the process of detecting the water level of the purified water tank 35 in the water level detecting means 110, first, the square wave signal of the AC type represented by the waveform of FIG. It is applied to the sensing electrodes 41 of the sensors 37 and 39 (hereinafter referred to as water level sensors).

At this time, when the amount of purified water in the purified water tank 35 is in contact with the other sensing electrodes 42 of the water level sensors 37 and 39, the 9th is also applied to the sensing electrodes 42 of the water level sensors 37 and 39 through its own resistance of water. The square wave signal shown in FIG. 1 is transmitted to output a square wave represented by the waveform of FIG.

Accordingly, since the water level sensors 37 and 39 in the purified water tank 35 are electrolyzed due to the voltage difference between the sensing electrodes 41 and 42 of the water level sensors 37 and 39, the square wave shown in the waveform of FIG. The voltage is amplified through the buffer 113 composed of the capacitor C1 and the impedance amplifier 115 to output a square wave signal represented by the waveform of FIG.

Accordingly, the voltage difference between the both ends of the water level sensors 37 and 39 is kept constant, and the square wave signal (waveform of FIG. 9C) output from the impedance amplifier 115 passes through the capacitor C2 and has a constant delay time. Outputs a voltage pulse displayed as a waveform of 9d degrees.

The voltage pulse (waveform of FIG. 9d) passing through the capacitor C2 is amplified by the operational amplifier 116. When the amplified voltage is high level, the diode D2 is in the forward direction and the operational amplifier 116 is operated. The ripple component included in the voltage amplified through is filtered through the smoothing capacitor C3 and is input to the input terminal A / D of the control means 125.

On the other hand, when the voltage amplified by the operational amplifier 116 is at a low level, the diode D1 is in the forward direction and the voltage amplified through the operational amplifier 116 is applied to the inverting terminal (-) of the operational amplifier 116. As it is fed back, the square wave output signals of the level sensors 37 and 39 are smoothed, and the level sensing voltage is applied to both ends of the smoothing capacitor C3.

Accordingly, the control means 125 compares the water level detection voltage, which is the output voltage of the water level sensors 37 and 39 input through the input terminals A / D, with the reference voltage set in advance, to the water purification tank 35. While determining whether the purified water supplied to the full water level or the low water level is controlled so that a predetermined amount of purified water is stored in the purified water tank 35.

If, in the control means 125, the water level of the purified water tank 35 is determined to be above the 'low water level', the water purification operation of the water tank 35 waits until the water level drops below the low water level.

However, if it is determined that the water level of the purified water tank 35 is 'low water level', the control means 125 controls the water supply valve driving means 135 to perform a water purification operation for supplying purified water into the purified water tank 35. Output the signal.

Accordingly, the water supply valve driving means 135 supplies the power supply voltage applied to the water supply valve 57 under the control of the control means 125 to open the water supply valve 57.

When the water supply valve 57 is opened, raw water such as tap water starts to be supplied from the faucet 22 through the connector 23 into the water supply pipe 25, and the control means 125 is supplied into the water supply pipe 25 to supply the membrane. A control signal for driving the pressure pump 59 is output to the pump driving means 130 so as to boost the raw water flowing into the 29 to a predetermined pressure.

Therefore, the pump driving means 130 receives the control signal output from the control means 125 and supplies the power voltage applied to the pressure pump 59 to drive the pressure pump 59.

When the pressurized pump 59 is driven, raw water supplied from the tap 22 to the water supply 25 through the opening of the water supply valve 57 passes through the pretreatment filter 27 and various harmful organic compounds such as chlorine components. The material is removed, and the raw water passing through the pretreatment filter 27 flows into the membrane 29 through the water supply valve 57.

The raw water introduced into the membrane 29 is boosted to a predetermined pressure according to the driving of the pressure pump 59 to pass through the membrane 29. The raw water introduced into the membrane 29 is formed in the membrane 29. As it penetrates the membrane membranes of dogs, various heavy metals, carcinogens and bacteria contained in raw water are removed.

The raw water passing through the membrane 29 passes through the post-treatment filter 31 to remove odors such as toxic gases, and then performs a water purifying operation supplied into the water purification tank 35 through the water supply hole 33.

At this time, the water level supplied to the purified water tank 35 through the water supply hole 33, that is, the water level of the purified water tank sensed by the water level detecting means 110 and outputs the detected water level data to the control means 125.

That is, the square wave signal of the alternating current type represented by the waveform of FIG. 9a is generated from the waveform generating part 111, and it is applied to the sensing electrode 41 of the water level sensors 37 and 39, and purified water is supplied into the purified water tank 35. As the water level gradually increases, and the purified water contacts the other sensing electrodes 42 of the water level sensors 37 and 39, the sensing electrodes 42 of the water level sensors 37 and 39 are also shown in FIG. The square wave signal is transferred to output the square wave represented by the waveform of FIG.

Accordingly, the square wave voltage (waveform of FIG. 9b) transmitted to the sensing electrodes 42 of the water level sensors 37 and 39 is amplified through the buffer 113 composed of the capacitor C1 and the impedance amplifier 115 and the 9c. A square wave signal represented by the waveform of the figure is output.

Accordingly, the square wave signal (waveform of FIG. 9c) output from the impedance amplifier 115 outputs the voltage pulse represented by the wave form of FIG. 9d while passing through the capacitor C2.

The voltage pulse (waveform in FIG. 9d) passing through the capacitor C2 is amplified by the operational amplifier 116. When the amplified voltage is high level, the diode D2 is in the forward direction and the operational amplifier 116 The ripple component included in the voltage amplified through is filtered through the smoothing capacitor C3 and is input to the input terminal A / D of the control means 125.

On the other hand, when the voltage amplified by the operational amplifier 116 is at a low level, the diode D1 is in the forward direction and the voltage amplified through the operational amplifier 116 is applied to the inverting terminal (-) of the operational amplifier 116. As it is fed back, the square wave output signals of the level sensors 37 and 39 are smoothed, and the level sensing voltage is applied to both ends of the smoothing capacitor C3.

Accordingly, the control means 125 compares the water level detection voltage, which is the output voltage of the water level sensors 37 and 39 input through the input terminals A / D, with the reference voltage set in advance, to the water purification tank 35. Determine whether the purified water supplied to the full water level or the low water level.

If it is determined that the water level of the purified water tank 35 is full, the control signal is output to the water supply valve driving means 135 to stop the supply of purified water to the purified water tank 35.

Accordingly, the water supply valve driving means 135 shuts off the power supply voltage applied to the water supply valve 57 under the control of the control means 125 to close the water supply valve 57.

When the water supply valve 57 is closed, the control means 125 outputs a control signal for stopping the pressurized pump 59 to the pump driving means 130.

Therefore, the pump driving means 130 stops the pressure pump 59 by cutting off the power voltage applied to the pressure pump 59 under the control of the control means 125.

When the water supply valve 57 is closed and the pressure pump 59 is stopped, the supply of raw water supplied from the faucet 22 into the water supply pipe 25 is cut off so that purified water is no longer supplied into the purified water tank 35. .

As such, the control means 125 controls the opening and closing operation of the water supply valve 57 according to the water level of the purified water tank 35 sensed by the water level detecting means 110 so that a constant amount of purified water is always in the purified water tank 35. To be stored.

Then, the user operates the water intake lever 43 coupled to the front of the water purification tank 35 to take the purified water.

On the other hand, in the embodiment of the present invention, in the water level detection circuit for detecting the water level of the purified water tank 35, when the waveform generated from the waveform generator 111 is a square wave, the sensor output signal is smoothed through the half-wave rectifier circuit. Although the present invention has been described as an example, the present invention is not limited thereto. When the waveform generated from the waveform generator 111 is a sine wave, the present invention may be smoothed through a full-wave rectification circuit as shown in FIG. Of course, the same purpose and effect can be achieved.

According to the water level detection device of the water purifier according to the present invention as described above, it is possible to supply a square wave of the AC type to the water level sensor and to eliminate the voltage difference between both ends of the water level sensor to prevent sensor corrosion by electrolysis, It has the excellent effect of accurately detecting the water level to prevent overflow.

Claims (3)

The purified water tank for storing purified water while passing through a pretreatment filter, a membrane and a post-treatment filter, a water level sensing means for sensing the water level of the water purification tank, and the purified water according to the water level of the purified water tank sensed by the water level sensing means. In a water purifier composed of control means for controlling the water level of the tank, the water level detecting means is a level generating unit for generating a square wave and a square wave generated from the waveform generating unit to detect the level of the purified water tank A sensor, a buffer for amplifying and outputting the square wave signal sensed by the water level sensor so that a voltage difference across the level sensor does not occur, and a rectifying unit for smoothing the square wave signal output from the buffer and inputting it to the control means. Water level detection device for a water purifier, characterized in that there is. The water level sensor of claim 1, wherein the buffer comprises a capacitor and an impedance amplifier configured to amplify and output a square wave signal sensed by the level sensor so that a voltage difference between the level sensors is not generated. Device. The amplifier of claim 1, wherein the rectifier includes: a capacitor configured to receive a square wave signal output from the buffer and output a voltage pulse; an operational amplifier configured to amplify the voltage pulse output from the capacitor; and an amplified voltage output from the operational amplifier. And a feedback resistor for feeding back a half-wave rectified voltage, a feedback resistor for feeding back a half-wave rectified voltage signal, a load resistor connected to one side of the diode and grounded at the other side, and a voltage signal half-wave rectified by the diode. A water level detection device for a water purifier, characterized in that it comprises a smoothing capacitor for filtering a ripple component.