KR102143913B1 - Travelling Band Screen and Control Method thereof - Google Patents

Abstract

A moving band screen and a control method thereof are disclosed. A moving band screen and a control method thereof according to an embodiment of the present invention include a support frame installed in a water intake passage, a transfer chain, and a transfer chain drive motor; A plurality of screen baskets coupled to the transport chain; Inflow and outflow washing water pipes provided to clean the screen basket, sprinkling pipes rotatably provided between the inflow washing water pipes and outflow washing water pipes, and a washing water sprinkling device provided with a nozzle to spray washing water into the screen basket; Including, the washing water sprinkling device includes at least one electric valve for selectively opening and closing the nozzle, and the sprinkling pipe is provided in the first divided header pipe and the second divided header pipe provided in two rows, and the first divided header pipe. It includes a second nozzle provided in the first nozzle and the second split header pipe, and the first nozzle and the second nozzle are intersected so that the washing water sprayed toward the screen basket does not overlap, so that the first split header pipe or the second nozzle The first water supply mode in which washing water is supplied only to the divided header pipe, the second water supply mode in which washing water is simultaneously supplied to the first divided header pipe and the second divided header pipe, and the shut-off mode can be selected using an electric valve. have.

Description

The moving band screen and its control method TECHNICAL FIELD

The present invention relates to a movable band screen, and more particularly, to a movable band screen capable of increasing driving efficiency and a control method thereof.

Various industrial plants, such as power plants, desalination facilities, and water purification plants, are equipped with water intake facilities for intake of large amounts of water. A rotating screen device, such as a moving band screen, is one of the water intake facilities, and is a device that filters impurities such as aquatic organisms, fish and shellfish, garbage, and suspended matter from the water being taken out.

Korean Patent Registration No. 10-655469 (2006.12.11.) The rotating screen device disclosed in the document includes a drive sprocket installed on the upper side of the water intake passage and a drive motor for operating the drive sprocket, a driven sprocket installed under the water intake passage, and a transfer chain connecting the driving sprocket and the driven sprocket, and It has a plurality of screen baskets coupled to the chain. In such a rotating screen device, when the driving motor is operated, the screen basket coupled to the conveying chain rotates to filter out foreign substances, and the water to be intake passes through the screen basket on the intake channel.

According to an embodiment of the present invention, it is intended to provide a moving band screen that is excellent in cleaning a screen basket and can maximize driving efficiency, and a control method thereof.

According to an aspect of the present invention, a support frame installed in the water intake passage; A drive sprocket installed on the upper frame of the support frame, a driven sprocket installed on the lower frame of the support frame, a transfer chain connecting the drive sprocket and the driven sprocket, and a drive motor for driving the transfer chain; A plurality of screen baskets coupled to the transport chain; In order to clean the screen basket, the inflow and outflow washing water pipes provided in the width direction of the upper frame, the sprinkling pipe rotatably provided between the inflow and outflow washing water pipes, and the washing water can be sprayed to the screen basket. A washing water sprinkling device provided with a nozzle, wherein the washing water sprinkling device includes at least one electric valve for selectively opening and closing the nozzle, and the sprinkling pipe includes a first divided header pipe and a second divided header pipe provided in two rows, It includes a first nozzle provided in the first divided header pipe and a second nozzle provided in the second divided header pipe, and the first nozzle and the second nozzle are moved to be intersected so that the washing water sprayed toward the screen basket does not overlap. A band screen can be provided.

In addition, the electric valve is provided as a 3-way valve, a first water supply mode in which washing water is supplied only to the first divided header pipe or the second divided header pipe, and the washing water is provided to the first divided header pipe and the second divided header pipe. It is possible to select a second water supply mode and a cut-off mode for simultaneously supplying.

In addition, the electric valve is provided as a 4-way valve, a first water supply mode in which washing water is supplied only to the first split header pipe, and a second water supply mode that simultaneously supplies washing water to the first split header pipe and the second split header pipe. It is possible to select a water supply mode, a third water supply mode in which washing water is supplied only to the second split header pipe, and a cut-off mode.

In addition, the first split header pipe and the second split header pipe are provided in a rectangular shape in the longitudinal direction, and both ends of the first split header pipe include a wrap joint to enable rotation adjustment of the inlet washing water pipe and the outlet washing water pipe. It is connected, and the second split header tube may be fixedly provided to the first split header tube.

In addition, the first nozzles provided in the first split header pipe and the second nozzles provided in the second split header pipe may be alternately arranged in the width direction.

In addition, the first nozzle provided in the first split header pipe and the second nozzle provided in the second split header pipe are based on the horizontal direction in order to avoid overlapping spraying of washing water sprayed toward the screen basket moving in the vertical direction. It can be arranged inclined in one direction.

According to another aspect of the present invention, in a method for controlling a moving band screen including a washing water sprinkling device for spraying washing water for washing the screen basket, the washing water sprinkling device includes a first divided header tube and a second divided A header pipe, a first nozzle provided in the first split header pipe and a second nozzle provided in the second split header pipe, and an electric valve for supplying washing water to the first split header pipe and the second split header pipe. Including, a first water supply mode in which washing water is supplied only to the first divided header pipe or the second divided header pipe, and a second water supply mode in which washing water is simultaneously supplied to the first divided header pipe and the second divided header pipe, A method of controlling a moving band screen for selecting a cut-off mode using the electric valve may be disclosed.

In addition, when the screen basket is operated at a first speed, the controller operates one of the first split header tube and the second split header tube, and when the screen basket is operated at a second speed faster than the first speed, The first split header tube and the second split header tube may be operated simultaneously.

In addition, the control unit drives the screen basket at a first speed and then stops when the comparison-calculated water level difference is less than the first reference water level, and the first speed when the comparison-calculated water level difference is greater than the first reference water level and less than the second reference water level. And, when the comparison-calculated water level difference exceeds the second reference water level, it may be driven at a second speed.

The moving band screen and its control method according to an embodiment of the present invention vary the operating speed of the screen basket by using the water level difference between the inlet side and the outlet side of the water intake passage, and further clean the screen basket according to the operating speed of the screen basket. Since the amount of washing water sprayed by the washing water sprinkler device can be adjusted in various water supply modes, the operating efficiency of the moving band screen can be maximized.

In addition, in the washing water sprinkling device provided on the moving band screen according to an embodiment of the present invention, a sprinkling pipe provided between the inflow and outflow washing water pipes is rotatably provided in the washing water pipe to facilitate position adjustment. Since a plurality of nozzles are installed at a predetermined distance apart from each other up and down and left and right, each nozzle is installed inclined in a predetermined direction with respect to the width direction of the opposite screen basket, so the water for the screen baskets operated in the vertical direction of the washing water spray device There is no area where is unsprayed.

1 is a diagram illustrating a moving band screen according to an embodiment of the present invention.
2 is a front view showing a washing water spray device for a moving band screen according to an embodiment of the present invention.
3 is a side view showing a washing water sprinkling device of a moving band screen according to an embodiment of the present invention.
4 is a perspective view showing a sprinkling pipe of a washing water sprinkling device of a moving band screen according to an embodiment of the present invention.
5 is a plan view showing a washing water sprinkling device of a moving band screen according to an embodiment of the present invention.
6 is a view schematically showing the washing water sprayed toward the screen basket from the washing water sprinkling device of the moving band screen according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventors appropriately explain the concept of terms in order to describe their own invention in the best way. Based on the principle that it can be defined, it should be interpreted as a meaning and concept consistent with the technical idea of the present invention. Accordingly, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and do not represent all the technical ideas of the present invention, and thus various alternatives that can be substituted for them at the time of application It should be understood that there may be equivalents and variations.

1 is a diagram illustrating a moving band screen according to an embodiment of the present invention. Referring to the drawings, the moving band screen according to the present embodiment is installed in the water intake passage 1, and the lower part is fixed to the concrete structure 2 on the bottom side of the water intake passage 1, and the support frame 10 The driving sprocket 11 provided above the intake passage 1 of 10), the driven sprocket 12 installed under the support frame 10 adjacent to the bottom of the intake passage 1, and the driving sprocket 11 ) And a transport chain 13 connecting the driven sprocket 12, and a plurality of screen baskets 30 coupled to the transport chain 13.

In addition, the moving band screen has a drive motor 15 installed on the upper side of the support frame 10 to rotate the drive sprocket 11, and a tension device installed on the upper side of the support frame 10 to maintain the tension of the transfer chain 13 ( 16), a washing water sprinkling device 20 for cleaning foreign substances in the screen basket 30, a cover 18 covering them, and the like. In the upper concrete structure 3 above the water intake passage 1, a discharge water passage 4 for guiding the discharge of foreign substances washed by the washing water sprinkling device 20 may be formed.

The moving band screen configured as described above rotates the upper driving sprocket 11 by the operation of the driving motor 15, the transfer chain 13 rotates by the operation of the driving sprocket 11, and the transfer chain 13 ), a plurality of screen baskets 30 connected to each other rotates together with the transfer chain 13 to collect and remove impurities present in the water in the intake passage.

As shown in Fig. 1, the screen basket 30 located in the water intake passage 1 is rotated in a clockwise direction, while the side in which water is introduced rises and descends to the opposite side from which the water is introduced. The water in the water intake passage passes through the rotating screen basket 30, while foreign matter is filtered out and exited.

The foreign matter filtered by the screen basket 30 while passing through the moving band screen is lifted toward the driving sprocket 11 together with the screen basket 30 and then discharged by high-pressure washing water sprayed from the washing water sprinkling device 20, At the same time, the screen basket 30 is cleaned. That is, the washing water sprinkling device 20 allows foreign substances to be removed from the screen basket 30 by spraying high-pressure washing water from the inside of the rotating screen basket 30 to the outside, and the removed foreign substances are passed through the discharge channel 4. It is discharged to the outside.

2 is a front view showing the washing water sprinkler device according to the present embodiment, and FIG. 3 is an enlarged side view thereof.

Referring to the drawings, the washing water sprinkling device 20 according to the present embodiment includes an inlet washing water pipe 21 fixed in the width direction to the upper frame of a pair of support frames 10 guiding the screen basket 30 from both sides. ) And an outflow washing water pipe 22, and a sprinkling pipe 24 provided between the inflow and outflow washing water pipes 21 and 22 and having a plurality of nozzles 25.

The inlet washing water pipe 21 and the outlet washing water pipe 22 have one end fixed to the upper frame of the support frame 10, respectively, and the other end provided spaced apart so that the sprinkling pipe 24 can be interposed therebetween.

The washing water is introduced into the pipe through the inlet washing water pipe 21, and is sprayed toward the surface of the screen basket through the nozzle 25 provided in the sprinkling pipe 24, and an opening/closing valve 22a attached to the outflow washing water pipe 22 Use to prevent or pass washing water. The opening/closing valve 22a attached to the outflow washing water pipe 22 can be used for cleaning water around the screen by connecting an external hose.

A manual valve 21a and an electric valve 23 may be provided in the inflow washing water pipe 21. The manual valve 21a can manually control the opening and closing of the inflow washing water pipe 21, and the electric valve 23 is a 3-way or 4-way valve to variously select and open the path of water supplied to the sprinkling pipe 24. Can be provided. Details will be described later.

The sprinkling pipe 24 is rotatably coupled to both ends of the inlet and outlet washing water pipes 21 and 22, and is provided so that the spray angle of the nozzle 25 can be easily adjusted. To this end, in the inlet and outlet washing water pipes 21 and 22, a ring-shaped lap joint flange 26 is rotatably provided on the connection side of the sprinkling pipe 24, and the sprinkling pipe 24 has a lap joint flange 26 and A bolt flange 27 that can be fastened is provided. The wrap joint flange 26 and the bolt flange 27 are fastened with a plurality of bolts (B) along the circumferential direction. Although not shown in detail, stud ends, gaskets, etc. are inserted between the bolt flange 27 and the wrap joint flange 26 to close and seal the connection parts of the washing water pipes 21 and 22, and these connecting parts are Hereinafter, it is collectively referred to as lap joint.

The sprinkling pipe 24 may include a first split header pipe 24a and a second split header pipe 24b. The first split header pipe 24a and the second split header pipe 24b are branched from the motorized valve 23 of the inflow washing water pipe 21 and are arranged side by side toward the screen basket 30. The electric valve 23 includes a first branch connector 23a and a second branch connector 23b, and the first branch connector 23a uses a first split header tube 24a and a wrap joint. Rotatable connection and the second branch connector (23b) is connected to the second split header tube (24b) rotating along the first split header tube (24a) using a flexible hose (23c).

A plurality of first nozzles 25a are arranged at predetermined intervals along the length direction in the first split header tube 24a, and a plurality of second nozzles 25b are arranged along the length direction in the second split header tube 24b. They are arranged at predetermined intervals. The first nozzle 25a and the second nozzle 25b are intersected so that the washing water sprayed toward the screen basket 30 does not overlap vertically and horizontally.

Looking in more detail with reference to FIG. 3, the first split header pipe 24a and the second split header pipe 24b may be provided as rectangular pipes, respectively. The first split header pipe 24a and the second split header pipe 24b, which are rotatably provided in the inflow and outflow washing water pipes 21 and 22 through the wrap joint, are adjacent to each other due to the rectangular shape and can be in contact with each other. Therefore, it is easy to adjust the angle of the nozzles 25, and since the interval between the nozzles 25 is narrow, the washing water can be sprayed at a more dense vertical interval.

The plurality of first nozzles 25a provided in the first divided header pipe 24a and the plurality of second nozzles 25b provided in the second divided header pipe 24b are respectively drawn from the same side of the divided header pipe. It may be alternately installed at "A gap (about 400mm)" of 2, and the screen basket 30 may be installed to spray washing water by being spaced apart by "B gap (about 550mm)" of FIG. 3. In addition, each nozzle may spray the washing water by facing the screen basket 30 which rotates at an angle α of about 6 degrees upward in the horizontal direction.

On the other hand, the screen basket 30 includes a filter net 31 for filtering foreign substances and a basket frame 32 in the form of a substantially square frame for supporting the filter net 31. The screen basket 30 can move along the transfer chain 13 by bolting both sides of the basket frame 32 to the transfer chain 13. The inside of the basket frame 32 may be filled with a foam member 33 made of a foamed polypropylene material so as to have sufficient rigidity while reducing weight. Since the screen basket 30 filled with the foam member 33 does not allow water to enter the screen basket even if it is submerged in water, the weight of the screen basket 30 is reduced, thereby further reducing the driving load of the moving band screen.

4 to 6 are views schematically showing the spraying range of the water spray pipe 24 and the washing water sprayed from the water spray pipe 24 according to the present embodiment.

First, as shown in FIG. 4, a plurality of first nozzles 25a provided in the first divided header pipe 24a and a plurality of second nozzles 25b provided in the second divided header pipe 24b are divided respectively. It may be alternately installed at intervals A on the same direction surface of the header pipe, and the screen basket 30 is spaced apart at intervals B to spray washing water.

In addition, as shown in FIG. 5, the washing water sprayed from the first nozzle 25a and the second nozzle 25b may be set to spread toward the front at an angle θ1 of about 55 degrees. The 55 degree interval is to allow the washing water to partially overlap in the width direction of the screen basket 30 to be ejected.Through this, the washing water does not reach the width direction of the screen basket 30 moving in the vertical direction of the watering pipe 24. There are no dead zones that do not exist.

In addition, as shown in Fig. 6, the first nozzle 25a and the second nozzle 25b sprayed toward the screen basket 30 are the same direction and angle with respect to the horizontal direction at an angle of θ2 (about 1 to 2 degrees). It can be arranged in an inclined manner. If the plurality of first nozzles 25a (or the plurality of second nozzles 25b) all spray the washing water at a width of 55 degrees in the same horizontal direction, in both sections overlapping partly, the flow of the water flows due to interference between neighboring washing water. The strength is bound to weaken.

Therefore, by arranging the plurality of nozzles 25a and 25b to be uniformly inclined in the same direction with respect to the horizontal direction as described above, the washing water in the width direction of the screen basket 30 moving up and down while avoiding overlapping part of the washing water There are no dead zones that do not reach.

Then, the operation of the moving band screen including the washing water sprinkling device 20 provided as described above will be described. Prior to the description, the moving band screen according to the present embodiment may further include a control device 40 provided on the concrete structure 3 above the water intake passage 1.

The control device 40 is provided in the form of a control panel, and as shown in FIG. 1, the control unit 41, the water level detection units 42 and 43 and the electric valves respectively installed on the upper concrete structure on the inlet and outlet sides of the water intake passage It includes a valve control unit 44 for driving 23). An ultrasonic level sensor may be employed as the water level sensing units 42 and 43, and includes a first water level sensing unit 42 provided on the inlet side of the water intake passage and a second water level sensing unit 43 provided on the outlet side. do.

The control unit 41 selectively opens and closes the electric valve 23 of the washing water sprinkling device 20 by operating the valve control unit 44 by using the difference in water level on the inlet and outlet sides of the water intake passage detected through the water level detection unit. The controller 41 may include a touch screen, a timer for automatic operation, an inverter, and the like as data input/output means to input preset values.

The operation of the screen basket of the moving band screen and the operation of spraying washing water using the above-described control device 40 will be described in detail below.

First, the control unit 41 detects the water level on the inflow side of the intake channel using the first water level detection unit 42, and detects the water level on the outflow side of the intake channel using the second water level detection unit 43.

Subsequently, the control unit 41 calculates the water level difference using the water levels sensed by the first water level detection unit 42 and the second water level detection unit 43, respectively, and calculates the calculated water level difference as a first reference water level (100 mm). Compare with

When the compared water level difference value is less than the first reference water level, the control unit 41 starts the screen basket 30 when a preset time has elapsed by the timer and drives it at a low first speed (2.0 m/min). , This low-speed first speed (2.0m/min) is maintained for a predetermined time. When the predetermined time elapses, the screen basket 30 stops operating, and if the predetermined time has not elapsed, the screen basket 30 is driven at a low first speed (2.0 m/min) until elapsed.

At this time, the washing water sprinkling device 20 is a first water supply mode in which washing water is sprayed only from the first nozzle 25a or a third water supply that sprays washing water only from the second nozzle 25b in response to the low-speed operation of the screen basket 30. Can be operated in mode. Selection of the first and third water supply modes in which a small amount of washing water is injected and a shut-off mode in which the washing water is stopped may be selected through the control of the 3-way or 4-way electric valve 23. When the screen basket 30 is operated, the washing water sprinkling device 20 operates together, and stops when the screen basket 30 is stopped. That is, the washing water sprinkling device 20 stops the operation when a predetermined time set along the screen basket 30 has elapsed, and if the predetermined time has not elapsed, the first or second water spray device 20 follows the low-speed screen basket 30 until it elapses. It is operated in 3 water supply mode.

On the other hand, when the comparatively calculated water level difference value is greater than the first reference level and less than the second reference level (200 mm), the control unit 41 drives the screen basket 30 at a low first speed (2.0 m/min), When the water level difference value is continuously detected while driving at the first low speed (2.0 m/min) and the water level difference value falls below the first reference level, the first low speed (2.0 m/min) is set for a predetermined time. The screen basket 30 is held for a while, and when a predetermined time elapses, the screen basket 30 is stopped. If the predetermined time has not elapsed, the screen basket 30 is driven at a low first speed (2.0 m/min) until the elapsed.

At this time, the washing water sprinkling device 20 is also operated to remove impurities stuck in the screen basket 30 operating at a low speed. The washing water sprinkling device 20 is a first water supply mode in which washing water is sprayed only from the first nozzle 25a, which is a small amount of spray, corresponding to the screen basket 30 operated at a low speed, or a third water spraying water is sprayed only from the second nozzle 25b. It can be operated in water supply mode.

In addition, the control unit 41 compares the washing water sprinkling device 20 like the screen basket 30 and the calculated water level difference value exceeds the first reference water level and is equal to or less than the second reference water level (200 mm), the first water supply mode or the third water supply. When the water level difference value falls below the first reference water level by continuously detecting the water level difference value, the first water supply mode or the third water supply mode is maintained for a predetermined period of time, and the washing water sprinkling device ( 20) is stopped, and if a predetermined time has not elapsed, the washing water sprinkling device 20 is driven until elapsed.

On the other hand, when the compared water level difference value exceeds the second reference water level (200 mm), the controller 41 moves the screen basket 30 to a second speed (4.0 m/min), which is faster than the first speed (2.0 m/min). m/min) and continuously detecting a water level difference value while driving at a high-speed second speed (4.0 m/min), and when the water level difference value exceeds the first reference level and falls below the second reference level, the screen basket ( 30) is driven at a low first speed (2.0m/min) and the water level difference value is continuously detected while driving at a low first speed (2.0m/min) so that the water level difference value is less than the first reference level. If the first speed (2.0m/min), which is low, is maintained for a predetermined time, the screen basket 30 is stopped when a predetermined time elapses, and if the predetermined time has not elapsed, the screen basket ( 30) is driven at the first low speed (2.0m/min).

At this time, the second water supply mode in which a large amount of washing water is simultaneously sprayed from the first nozzle 25a and the second nozzle 25b in response to the washing water sprinkling device 20 in order to remove impurities stuck in the screen basket 30 operating at high speed. Works as The selection of the second water supply mode and the cut-off mode may be made through the control of the 3-way or 4-way electric valve 23.

That is, like the screen basket 30, the control unit 41 drives the washing water sprinkling device 20 in the second water supply mode, which is a large amount of washing water, when the compared water level difference value exceeds the second reference water level (200 mm). When the water level difference value is continuously detected while driving in the second water supply mode and the water level difference value exceeds the first reference water level and is below the second reference water level, the first water supply mode or the third water supply mode, which is sprayed with a small amount of washing water, is operated. Or, if the water level difference value is below the first reference level by continuously detecting the water level difference value while driving in the third water supply mode, a small amount of washing water is sprayed in the first and third water supply modes for a predetermined time and then a predetermined time elapses. If the operation is stopped, and if a predetermined time has not elapsed, the washing water sprinkler 20 is driven in the first water supply mode or the third water supply mode until the elapsed.

In the above description, the control unit 41 individually controls the operation of the screen basket and the washing water sprinkling device by using the difference in water level on the inlet and outlet side of the water intake passage, but the present invention is not limited thereto, and for example, the washing water sprinkling device is a screen basket. It can be driven according to the presence or absence of operation. In addition, the control unit may, of course, switch and control the operation based on the load of the driving screw that varies according to the weight of the impurities by providing a torque sensor on the driving sprocket instead of the water level difference.

1..Intake passage 10..Support frame
13..Transfer chain 20..Wash water spray device
21,22..inflow and outflow washing water pipe 21a..manual valve
23..electric valve 24..spray piping
24a..first division head pipe 24b..second division head pipe
25..Nozzle 26..lap joint
30.. Screen basket 31. Filter net
40..control device 42..first water level detection unit
43..Second water level detection unit

Claims (10)

A support frame installed in the water intake passage;
A drive sprocket installed on the upper frame of the support frame, a driven sprocket installed on the lower frame of the support frame, a transfer chain connecting the drive sprocket and the driven sprocket, and a drive motor for driving the transfer chain;
A plurality of screen baskets coupled to the transfer chain;
In order to clean the screen basket, the inlet washing water pipe and the outlet washing water pipe provided in the width direction on the upper frame, the sprinkling pipe rotatably provided between the inlet washing water pipe and the outlet washing water pipe, and washing water can be sprayed to the screen basket. Including; a washing water sprinkler device provided with a nozzle so that,
The washing water spray device includes at least one electric valve for selectively opening and closing the nozzle,
The sprinkling pipe includes a first split header pipe and a second split header pipe provided in two rows, and a plurality of first nozzles and a second split header pipe provided along the width direction in the first split header pipe in the width direction. It includes a plurality of second nozzles provided along,
The first nozzles and the second nozzles are alternately disposed along the width direction to suppress overlapping of the washing water sprayed through the first nozzle and the washing water sprayed through the second nozzle,
In order to suppress the overlapping of the washing water sprayed through the plurality of first nozzles and the washing water sprayed through the plurality of second nozzles overlapping each other, each nozzle is clockwise or counterclockwise based on the horizontal direction. Is provided inclined in the direction,
The first split header pipe is a moving band screen rotatably connected between the inlet washing water pipe and the outlet washing water pipe,
The electric valve includes a first water supply mode in which washing water is supplied only to the first divided header pipe or the second divided header pipe, and a second water supply mode in which washing water is simultaneously supplied to the first divided header pipe and the second divided header pipe. , It is provided to be able to select a blocking mode for blocking the supply of washing water to the first divided header pipe and the second divided header pipe,
Calculates and compares the water level difference by sensing the inflow and outflow water level of the water intake passage, controls the operation of the screen basket so that the rotation speed of the screen basket increases in proportion to the water level difference, and the rotation speed of the screen basket is A control unit for controlling the electric valve to sequentially operate the shut-off mode, the first water supply mode, and the second water supply mode as the number increases; further comprising,
The second split header pipe is coupled in surface contact with the first split header pipe so as to rotate along the first split header pipe, and is connected to the inflow washing water pipe through a flexible hose. The method of claim 1,
The electric valve is a moving band screen provided as a 3-way valve.
delete The method of claim 1,
The first split header tube and the second split header tube are provided in a rectangular shape along the longitudinal direction,
Both ends of the first split header pipe include a wrap joint and are rotatably connected to the inlet washing water pipe and the outlet washing water pipe.

delete delete In the control method of the moving band screen according to claim 1,
A method of controlling a moving band screen for selecting the first water supply mode, the second water supply mode, and the shut-off mode using the electric valve. The method of claim 7,
The control method for controlling the moving band screen selectively operates at least one of the first split header tube and the second split header tube according to the rotation speed of the screen basket operating corresponding to the water level difference. The method of claim 8,
The control unit
When the screen basket is operated at a first speed, one of the first split header tube and the second split header tube is operated,
When the screen basket is operated at a second speed faster than the first speed, the first split header tube and the second split header tube are simultaneously operated. The method of claim 9,
The control unit
When the comparison and calculated water level difference is less than the first reference water level, the screen basket is driven at the first speed and then stopped,
When the comparison and calculated water level difference is greater than the first reference water level and less than the second reference water level, it is driven at a first speed,
A method of controlling a moving band screen that drives at a second speed when the comparison-calculated water level difference exceeds the second reference water level.

Images