KR101325692B1 - Water purification apparatus - Google Patents

Abstract

A water purification device for seawater purification is disclosed. According to an embodiment of the present invention, a water purifying apparatus includes: a main body formed to float on the sea; Control unit for controlling the speed and direction of the main body; Propulsion unit is installed in the lower portion of the main body for generating a driving force to be movable in the sea; A steering part installed on the main body to adjust the direction of the main body; An inlet installed at an outer side of the main body to introduce seawater into the inner side of the main body; Water purification unit for filtering the seawater introduced into the body through the inlet; And a discharge part for discharging the purified sea water through the purified water part.

Description

Water Purifier {WATER PURIFICATION APPARATUS}

The present invention relates to a water purifier, and more particularly, to a water purifier for purifying seawater contaminated by foreign matter.

In the process of building a ship, various painting works are carried out. The painting works include a touch up for painting the paint with a brush, a spray using a paint gun, and a power brush for grinding the painted surface. Particularly, the final painting work is performed on the quay wall. After finishing the painting work on the painting surface of the ship, the spray painting work is performed using the coating gun.

In the finishing work and spraying process, paint dust generated by the finishing work and the paint that is not adsorbed on the paint surface are scattered, and the seawater is contaminated to cause seawater contamination.

In order to prevent seawater contamination by paint dust, etc., the work is performed by covering the protective film on the sea surface during finishing and spraying. However, the work to cover the sea surface with such a prevention film requires a lot of time and manpower, thereby reducing the productivity of the work.

Korean Patent Application No. 2008-0079701 proposes a filtration device for suction filtration of suspended solids suspended at sea level and polluting sea water.

The prior art document provides a configuration for separating a floating vessel and the like from the sea surface and performing a work by separating the filtration device with a suction line from the work line. The filtration device fixes the swelling in the lower part of the filtration device so that the upper side of the suction port is exposed to the upper part of the water surface by buoyancy, and the seawater sucked through the suction port flows into the filtration device, and the suspended matter is filtered through the bag of the filter. Filtered. If the suspended solids accumulate in the bag by continuous filtration, the suspended solids are pumped to the dehydrator of the working ship. The filtered seawater is also transported through hoses to certain areas, such as farms.

Such a filtration device is separated from the working vessel to filter the seawater containing the suspended matter at a certain position of the sea surface, this prior document is to filter and move quickly the paint dust generated during the painting operation of ship drying Not easy

Korean Intellectual Property Office Application No. 2008-0079701

One embodiment of the present invention is to provide a water purification device for quickly removing foreign matter suspended in the sea and purifying sea water.

One embodiment of the present invention is to provide a water purification device that can be remotely controlled at sea level.

According to an aspect of the present invention, the main body is formed to be floating on the sea, the control unit for controlling the speed and direction of the main body, the propulsion unit is installed in the main body to generate a propulsion force to be movable in the sea, the main body A steering part installed in the main body to adjust the direction of the inlet, an inlet part installed at an outer side of the main body to introduce seawater into the main body, a water purifying part filtering the seawater introduced into the main body through the inlet part, and the And a discharge part for discharging the purified seawater through the water purification part, wherein the inlet part includes a pipe member having one end of the inlet port through which the sea water flows, and a part of the inlet port is located on the sea surface, and the pipe member includes: It is formed so that the width of the cross section of the pipe member becomes wider from the main body side toward the inlet side, A filtering net is installed, and the water purification unit is located in the downstream side of the pipe member in the flow direction of the seawater flowing through the pipe member, and the immersion tank in which foreign matter suspended in the seawater can be precipitated and stored. A centrifugal filter for filtering the seawater that has passed, and a filter provided at at least one position between the pipe member and the submersion tank, between the submersion tank and the centrifugal filter, and downstream of the centrifugal filter, and passing through the centrifugal filter. A water purifier is provided, through which one seawater is discharged to the outside of the main body.

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At this time, it may include a pump installed in the main body so that the seawater introduced through the pipe member to the water purification unit.

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At this time, a flexible fluid flow tube may be installed between the other end of the tube member and the submersion tank.

On the other hand, the filter material storage unit located on the upper side of the body; The apparatus may further include moving means for moving the tubular member so as to move the manure material that is filtered by the strainer and positioned in front of the tubular member to the manure material reservoir.

In this case, the moving means may include an elastic bar member having one end rotatably installed between the main body or the water purification unit and the other end coupled to one side of the tubular member, and a drive motor capable of rotating the bar member. have.

On the other hand, the water purification unit includes at least one of the immersion tank, the vibration generator may be installed in at least one of the immersion tank so that the foreign matter can be more easily precipitated in the immersion tank.

On the other hand, the centrifugal filter, a sediment outlet for discharging the sediment separated by the centrifugal filter is formed, it may include a sediment container for collecting the sediment discharged through the sediment outlet.

On the other hand, the underwater camera is installed in the lower front of the main body to observe the underwater, the distance sensor for detecting the object and the distance around the main body and the inside of the main body is installed inside the main body to detect whether or not It may further include at least one of the moisture detection sensor.

On the other hand, the buoyancy is generated by the controller when the solar panel is installed on the outside of the main body and the ingress of the main body is detected by the charger and the moisture sensor to be installed outside the main body to store the electricity generated from the solar panel. It may further include at least one of the buoyancy generating unit is installed on the outside of the main body.

The water purifying apparatus according to an embodiment of the present invention may move while removing the foreign matter floating on the sea surface through the water inlet in the body of the seawater introduced through the inlet provided in the outer portion of the main body.

The water purifying apparatus according to an embodiment of the present invention may control the water purifying apparatus for removing foreign matter suspended in the sea surface by remotely controlling the water purifying apparatus.

1 is a schematic diagram of a water purifying apparatus according to an embodiment of the present invention.
2 is a schematic diagram of a water purifying unit of the water purifying apparatus according to an embodiment of the present invention.
Figure 3 is a schematic diagram of the process of collecting the suspended solids by the moving means of the water purifying apparatus according to an embodiment of the present invention.
4 is a block diagram showing the function of the controller of the water purifying apparatus according to an embodiment of the present invention.
5 is a block diagram showing the internal functions of the remote control console of the water purifying apparatus according to an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, one Example of the water purifier 1 of this invention is described in detail with reference to an accompanying drawing.

1 is a schematic diagram of a water purifying apparatus 1 according to an embodiment of the present invention. 2 is a schematic diagram of the water purifying unit 600 of the water purifying apparatus 1 according to the embodiment of the present invention. 3 is a schematic diagram of a process for collecting suspended solids by the moving unit 170 of the water purifying device 1 according to an embodiment of the present invention. 4 is a block diagram showing the function of the control unit 500 of the water purifying device 1 according to an embodiment of the present invention.

1 to 4, the water purifying device 1 according to the present embodiment is a water purifying device which is located on the sea surface and infiltrated the seawater contaminated with the foreign matter to filter the foreign matter and discharge the filtered seawater again. . At this time, the water purification device according to the present embodiment can be controlled remotely by the user using the remote control console 700.

Water purifying apparatus 1 according to an embodiment of the present invention is the main body 100, the control unit 500, the driving unit 200, the steering unit 300, the inlet unit 400, the water purification unit 600 and the discharge unit ( 800).

The main body 100 has a shape that can move in the sea and float in the sea to filter the sea water. For example, the body may be formed in a shape similar to a ship as shown in FIG. 1, but the shape of the body is not limited thereto. In the main body 100, various devices may be installed or included to perform a function of the water purifying device 1 according to an embodiment of the present invention.

The propulsion unit 200 is installed below the main body 100 to generate a driving force so that the main body 100 can move. The propulsion unit 200 includes a propeller 210 that can rotate by a motor or the like installed in the main body 100. Then, the driving unit 200 may adjust the speed of the main body 100 by adjusting the rotational speed of the motor.

In addition, the steering unit 300 is installed in the main body 100 to adjust the direction of the main body 100 to obtain a driving force to move. The steering unit 300 adjusts the moving direction of the main body 100 by changing the flow of sea water due to the rotation of the propeller 210.

In the propulsion unit 200 and the steering unit 300 of the water purifying device 1 according to the present embodiment, an azimuth thruster form or propulsion unit 200 and the steering unit 300 are integrally formed. It may be implemented in the form.

In more detail, as can be seen in Figure 1, the azimuth thrust form consisting of the propulsion unit 200 and the steering unit 300 integrally, the propeller 210 of the propulsion unit 200 is perpendicular to the main body 100 It is located inside the tunnel member 310 to rotate on the lower side of the main body 100 about one axis.

In this case, the tunnel member 310 is coupled to the connecting portion 311 having a tubular shape, and the connecting portion 311 is rotatably installed about an axis perpendicular to the main body 100 at the lower portion of the main body 100.

Accordingly, by rotating the tunnel member 310 through the connecting portion 311, the flow of seawater flowing into the propeller 210 rotating inside the tunnel member 310 and the flow direction of seawater discharged from the propeller 210 are changed. It may be, by adjusting the direction of the tunnel member 310 as described above to adjust the moving direction of the main body 100.

At this time, it is preferable to install the plurality of tunnel members 310 and the propellers 210 in the main body 100 so as to more easily move the position and posture of the main body 100.

In an embodiment of the present invention, the azimuth thruster is illustrated as a configuration of the propulsion unit 200 and the steering unit 300 for moving the water purifying device 1, but various known propulsion apparatuses and steering apparatuses are illustrated. Can be used as a configuration for moving or changing the main body of the water purifying apparatus according to the present embodiment.

On the other hand, according to an embodiment of the present invention, in order to suck the seawater containing foreign matter suspended in the sea surface to the main body 100, the inlet 400 for sucking the sea water is provided on the outer side of the main body 100 .

The inlet 400 may include an inlet 410 through which seawater is introduced and a pipe member 430 provided at one end of the inlet 410. At this time, in order to quickly introduce the seawater containing the foreign matter, a plurality of inlets 400 may be installed on the outer side of the main body 100.

At this time, referring to Figure 1, to facilitate the inflow of sea water, the pipe member 430 may be formed in the form that the width of the cross section of the pipe member 430 toward the inlet 410 side from the main body side.

In addition, a portion of the pipe member 430 may be disposed on the sea surface and the remaining portion of the pipe member 430 may be disposed under the sea surface so that seawater containing foreign matter floating on the sea surface is introduced.

On the other hand, referring to Figure 2, in order to filter foreign matter large particles floating on the sea surface, the filtering net 450 is installed inside the pipe member 430. When foreign matter having large particles, for example, foreign matter such as wood or styrofoam, flows into the interior of the water purifying apparatus 1, the filtration function of the water purification unit 600 for filtering the foreign matter having small particles is significantly lowered. In the water purifying apparatus 1 according to the embodiment, the foreign matter having such large particles is filtered by the tubular member 430.

The seawater including foreign matter on the sea surface first filtered by the pipe member 430 is purified by the water purification unit 600 inside the main body 100 of the water purification device 1 and discharged out of the main body 100 again. do.

Referring to FIG. 4, the main body 100 may include a controller 500 for controlling the propulsion unit 200 and the steering unit 300. In addition, the control unit 500 functions to control operations of the pump 900, the buoyancy generating unit 150, the moving unit 170, and the water purifying unit 600. The controller 500 receives signals measured from the load cell 655, the distance sensor 130, and the moisture sensor 140, and receives a charging state from the charger 111. In addition, the controller 500 receives an image photographed by the underwater camera 120.

At this time, the transmission and reception unit 510 that performs a function of transmitting and receiving a signal with the remote control console 700 may be installed in the control unit 500. The controller 500 transmits and receives signals to and from the remote control console 700 through the transceiver 510.

Referring to FIG. 2, the purified water unit 600 according to the present exemplary embodiment may obtain seawater filtered from the foreign matter through various components in the purified water 600, which is introduced through the inlet 400.

The water purification unit 600 installed in the main body 100 to filter the foreign matter suspended in the sea surface, the first filter 610, the fluid flow pipe 620, the pump 900, the first submerged tank 630, the second The submersible tank 640, the centrifugal filter 650, and the second filter 670 may be included. The water purification unit 600 filters foreign matters floating on the sea surface, for example, foreign matters having small particles such as paint dust generated during ship construction.

The first filter 610 is configured to primarily filter the seawater introduced through the inlet 400 in the water purification unit 600, and is located downstream of the pipe member 430 in the flow direction of the inflowing seawater. .

In this case, referring to FIG. 2, in the present embodiment, the seawater is introduced into the main body 100 of the water purification device 1 through the inlet 400 located on the left side of the water purification device 1, and then moves in the right direction. It is purified while. In the present specification, the process from the left to the right is defined as the flow direction of the seawater as viewed in FIG.

The first filter 610 may filter foreign matter except for paint dust, for example, in seawater in which foreign matters having large particles are filtered out by the strainer 450.

Meanwhile, a flexible fluid flow tube 620 may be installed downstream of the first filter 610. For example, the fluid flow tube 620 may be in the form of a bellows. By the bellows-shaped fluid flow tube 620, a portion of the inlet 410 may be adjusted to be located on the sea surface to facilitate the inflow of seawater.

On the other hand, the pump 900 is installed in the main body 100 so that the seawater flows into the water purification unit 600 through the inlet 400. For example, the pump 900 may be located between the fluid flow pipe 620 and the first immersion tank 630 to introduce seawater, but the position of the pump is not limited thereto.

The first immersion tank 630 is located downstream of the first filter 610 in order to separate small foreign substances such as paint dust from the seawater by sedimentation with respect to the seawater filtered by the first filter 610. . The foreign matter remaining in the seawater passing through the first filter 610, for example, paint dust has a higher specific gravity than the seawater and sinks to the bottom of the first immersion tank 630 to be separated from the seawater.

At this time, a first vibration generator 631 is provided to vibrate seawater in order to easily settle the paint dust floating on the sea surface in the first immersion tank 630.

The first vibration generator 631 is installed at one side of the first immersion tank 630 to generate a constant vibration for seawater containing dust and the like.

Paint dust has a higher specific gravity than seawater and sinks to the bottom, but it takes a certain time to settle by surface tension of seawater. Therefore, the first vibration generator 631 is operated to quickly settle the paint dust. [0030] Meanwhile, the first immersion tank is not settled completely in the first immersion tank 630, but the first immersion tank to settle the paint dust suspended in the sea water. Downstream of 630, a second submersion tank 640 connected through a first connecting conduit 632 may be located.

At this time, the second vibration generator 641 may be installed in the second immersion tank 640 so that the paint dust easily precipitates in the second immersion tank 640.

At this time, the paint dust submerged in the immersion tanks (630, 640) may collect the paint dust precipitated in the immersion tanks (630, 640) by disassembling the water purification unit 600 after the operation is completed.

On the other hand, downstream of the second immersion tank 640, the second immersion tank 640 and the second connection in order to filter the seawater filtered through the first immersion tank 630 and the second immersion tank 640 again A centrifugal filter 650 connected via conduit 642 is installed. In this case, the centrifugal filter can be passed through the first immersion tank 630 and the second immersion tank 640 without any fine paint dust deposited in the first immersion tank 630 and the second immersion tank 640. By 650, the seawater is filtered once again. Centrifugal filter 650 is a filter using a centrifugal force to rotate the introduced seawater to separate the fine paint dust from the seawater.

On the other hand, the fine paint dust and the like separated by the centrifugal filter 650 may be discharged to the outside through the sediment outlet 651 located on the lower side of the centrifugal filter 650.

At this time, the paint dust discharged to the outside through the sediment discharge port 651 may be collected by the sediment container (653).

In this case, a weight sensing sensor, for example, a load cell 655, may be installed at a lower side of the sediment container 653 to measure the collection amount of the paint dust collected in the sediment container 653.

The load cell 655 measures the collection amount of the paint dust and the sediment container 653 through the control unit 500 (see FIG. 6) of the main body 100 when the collected amount is outside the prescribed capacity limit of the sediment container 653. Inform the user that the replacement is required.

In order to discharge the seawater filtered through the centrifugal filter 650 to the outside of the main body 100, the discharge portion 800 is installed on the downstream side of the centrifugal filter 650 in the flow direction of the seawater. The discharge portion 800 is formed, for example, in the form of an L-shaped tube so that the sea water filtered to the sea outside the main body 100 can be discharged in the downward direction from the top of the sea surface.

Meanwhile, a second filter 670 may be installed between the centrifugal filter 650 and the discharge part 800. This second filter 670 is positioned to finally filter foreign matter, for example paint dust, which has not been filtered through the first submersion tank 630, the second submersion tank 640, and the centrifugal filter 650. do.

On the other hand, the water purifying device 1 according to an embodiment of the present invention is able to move the pipe member 430 to collect the suspended solids (D) located in the inlet 400 is filtered by the strainer 450 The moving means 170 and the manure material storage unit 160 capable of collecting the suspended solids D having a large particle size may be provided.

3 illustrates a state in which the suspended solids D are collected using the moving unit 170.

Referring to FIG. 3, the moving unit 170 may include an elastic bar member 171 and a hinge portion 173. For example, the flexible bar-shaped member 171 consists of a hydraulic cylinder.

The hydraulic cylinder 171 is composed of a rod 171a and a cylinder 171b. One end of the rod 171a is rotatably installed on one side of the tube member 430. One end of the cylinder 171b is rotatably installed in the main body 100 or the water purification unit 600.

At this time, one end of the cylinder 171b is installed in the main body 100 or the water purification unit 600 through the hinge portion 173. In addition, the hydraulic cylinder 171 may be rotated by a driving motor (not shown) connected to the hinge portion 173.

On the other hand, the filter material storage unit 160 may be installed on the upper side of the main body 100 to collect the suspended particles (D) having a large particle trapped in the sieve (450).

The manure material storage unit 160 collects suspended solids D having a large particle size, such as wood and styrofoam. For example, the manure material storage unit 160 may be formed in a rectangular box shape with an open top. ) May be formed in the form of a rectangular box made of a wire mesh.

Accordingly, when the suspended solid material (D) having a large particle is caught in the strainer 450 of the pipe member 430 and the seawater contaminated with the foreign matter is not smoothly introduced through the inlet 400, the user moves the vehicle 170. Lifting the tubular member 430 by using the upper portion of the tubular member 430 is positioned on the filter material storage 160, the tubular member 430 is flipped over the sieve 450 of the tubular member 430 The suspended suspended solids (D) is poured into the filter material storage unit 160 and stored, and the inside of the tubular member 430 is emptied. When the pipe member 430 is placed on the sea surface while the pipe member 430 is empty as described above, the water purifying apparatus 1 returns to the filter net 450 in the pipe member 430 without a floating material having large particles. Can do integer operations

5 is a block diagram showing the internal functions of the remote control console 700 of the water purifying apparatus according to an embodiment of the present invention.

Referring to FIG. 5, the remote control console 700 according to the present embodiment may control the driving unit 200, the steering unit 300, the moving unit 170, and the water purification unit 600 of the water purifying device 1. have. In addition, the remote control console 700 can exhibit various operating states of the water purifying device 1.

In this case, the remote control console 700 may include a control signal input unit 710, a console controller 720, a console transceiver 730, a display unit 740, and a switch unit 750.

Meanwhile, referring to FIG. 1, according to one embodiment of the present invention, a charger 111 and a solar panel 110 may be installed in the main body 100 to supply power.

The solar panel 110 is installed in the main body 100 to absorb sunlight, and converts the absorbed solar energy into electrical energy to be stored in the charger 111. The charger 111 supplies the charged electricity to the propulsion unit 200, the steering unit 300, the moving unit 170, the water purification unit 600, and the like installed in the main body 100.

Meanwhile, according to one embodiment of the present invention, an underwater camera 120 for observing underwater in the front of the main body 100 may be installed. The underwater camera 120 functions to determine the pollution state of the seawater, the objects present in the seawater, and the seawater situation. The image observed through the underwater camera 120 is displayed to the user through the control unit 500 (see FIG. 4).

In addition, the lighting device 121 may be installed in the main body 100 so that the underwater camera 120 easily observes the underwater.

Meanwhile, according to one embodiment of the present invention, a plurality of distance detection sensors 130 may be installed outside the main body 100. The distance sensor 130 measures a distance to an external object from a location where the sensor is installed. In this way, an object existing around the main body 100 may be detected and a signal may be applied to the controller (see FIG. 4) to prevent a collision with an object around the main body 100.

Meanwhile, according to one embodiment of the present invention, a plurality of moisture detection sensors 140 may be installed inside the main body 100. The moisture detecting sensor 140 may prevent the sinking due to the immersion by applying a signal to the controller (see FIG. 4) when water of a predetermined size or more is detected inside the main body 100.

At this time, when an emergency situation that sinks occurs, the buoyancy generating unit 150 may be installed outside the main body 100 in order to generate buoyancy in the main body 100. The buoyancy generator 150 is operated by the controller 150 receiving the signal of the moisture sensor 140. The buoyancy generating unit 150 generates a sufficient buoyancy by injecting a gas having a specific gravity less than seawater in an emergency situation. For example, the buoyancy generating unit may be formed in the form of a bag made of an elastic material such as rubber that can generate buoyancy when gas is injected.

Water purifying apparatus 1 according to an embodiment of the present invention while removing the foreign matter floating through the water purifying part 600 in the body 100, the seawater introduced through the inlet 400 installed in the outer portion of the main body 100 I can move it. In addition, the water purifying device 1 according to an embodiment of the present invention may be remotely controlled through the remote control console 700 and may filter seawater.

As described above, the present invention has been described through limited embodiments and drawings, but the present invention is not limited thereto, and the present invention has been described below by the person skilled in the art to which the present invention pertains. Various modifications and variations are possible within the scope of the claims.

1: water purifier 100: main body
110: solar panel 120: underwater camera
130: distance sensor 140: moisture sensor
150: buoyancy generating unit 160: manure material storage unit
170: moving means 171: bar-shaped member
200: propulsion unit 210, 220: propeller
300: steering unit 310, 320: rudder
400: inlet 410: inlet
430: pipe member 500: control unit
510: transceiver unit 600: water purification unit
610: first filter 620: fluid flow tube
630: first submerged tank 640: second submerged tank
650: centrifugal filter 670: second filter
700: remote control console 800: discharge section
900: Pump

Claims (11)

Main body formed to float on the sea
Control unit for controlling the speed and direction of the main body
Propulsion unit is installed in the main body to generate a driving force to move the main body at sea
Steering portion installed in the main body to adjust the direction of the main body
An inlet installed at an outer side of the main body to introduce seawater into the inner side of the main body;
Water purification unit for filtering the seawater introduced into the main body through the inlet and
It includes a discharge unit for discharging the purified sea water through the water purification unit,
Wherein:
And a tube member having an inlet through which the seawater flows in at one end, the inlet member being positioned on the sea surface,
The pipe member is formed such that the width of the cross section of the pipe member is wider from the main body side toward the inlet side, and a strainer is provided on the inside,
The water purification unit,
Immersion tank which is located on the downstream side of the pipe member in the flow direction of the seawater flowing through the pipe member and the foreign matter suspended in the sea water can be precipitated and stored
A centrifugal filter for filtering the seawater passing through the immersion tank;
A filter installed at at least one position between the pipe member and the submersion tank, between the submersion tank and the centrifugal filter, and downstream of the centrifugal filter,
Sea water passing through the centrifugal filter is discharged to the outside of the main body through the discharge portion.
delete The method of claim 1,
And a pump installed in the main body so that the seawater introduced through the pipe member flows into the water purification unit.
delete The method of claim 1,
And a flexible fluid flow tube installed between the other end of the tube member and the submersion tank.
The method of claim 5, wherein
A manure material storage unit located on an upper side of the main body;
And a moving means for moving the tubular member so as to move the manure material that is filtered by the strainer and positioned in front of the tubular member to the manure material reservoir.
The method according to claim 6,
The moving means
An elastic bar member having one end rotatably installed between the main body or the water purification unit and the other end coupled to one side of the tubular member;
And a driving motor capable of rotating the bar-shaped member.
The method of claim 1,
The water purification unit includes at least one submerged tank,
A water purifier, wherein a vibration generator is installed in at least one of the immersion tanks so that the foreign matter can be more easily precipitated in the immersion tank.
The method of claim 1,
The centrifugal filter,
A precipitate outlet for discharging the precipitate separated by the centrifugal filter is formed,
Water purification device comprising a sediment container for collecting the sediment discharged through the sediment discharge port.
The method of claim 1,
An underwater camera installed under the front of the main body to observe the water;
A distance sensor for detecting an object around the main body and measuring a distance;
The water purifying apparatus installed in the main body further comprises at least one of a moisture detection sensor for detecting whether the inside of the main body is inundated.
11. The method of claim 10,
A charger installed outside the main body to store a solar panel installed outside the main body and electricity generated from the solar panel;
The water purifying apparatus further comprises at least one of buoyancy generating units installed outside of the main body so that buoyancy is generated by the controller when the water is detected by the moisture sensor.

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