Patent Description:
A water sluice gate is an important hydraulic structure configured to open or close a water channel, the water sluice gate mainly comprises a main movable portion, an embedded portion, and a hoisting device. Wherein, the main movable portion is configured to close or open an orifice and is generally known as a sluice gate. The embedded portion comprises a main rail, a guide rail, a hinge base, a bottom sill, etc., which are buried around the orifice to form a gate slot for movement of the sluice gate. Document <CIT> discloses for example an underwater cleaning device.

In actual use, debris such as stones, sludge, and construction waste may accumulate into the gate slot during long-term operation of the sluice gate, and therefore the debris needs to be cleaned and erosion pit-holes need to be repaired and patched regularly.

In prior art, underwater inspection and cleaning of a sluice gate is mostly done by means of underwater cleaning by a diver or a dredging pump: underwater inspection and cleaning by a diver has strict requirements of water flow velocity and water depth at the gate slot. Under a circumstance that the water flow velocity is fast and the water depth is high, it would be very difficult for a diver to conduct underwater inspection and cleaning, which would have high danger, low efficiency, and limited usage conditions. The use of a dredging machine to clean and suck out sediments on the inner wall or bottom of the gate slot in a state of underwater may be affected by multiple factors such as water flow, etc., which would cause the automatic cleaning equipment to tilt during movement along the gate slot, thus the sediment cleaning effect is adversely affected.

Therefore, the technical problem to be solved by the present invention is to overcome the defect in the prior art that an automatic cleaning equipment used for gate slot cleaning may be affected by multiple factors such as water flow, etc. in a state of underwater, which would cause the automatic cleaning equipment to tilt during movement along the gate slot and adversely affect the sediment cleaning effect. Thus, an underwater cleaning device for a gate slot and a use method thereof are provided.

To solve the above problem, the present invention provides an underwater cleaning device for a gate slot that comprises:.

In some embodiments, the climbing structure further comprises a movable base, a driving wheel is provided on the movable base, and the driving wheel is meshed with a gear rack on one side of a connection plate, and a first power member and a driven wheel are disposed in the movable base, the driving wheel and the driven wheel are respectively arranged on both sides of the connection plate, the driving end of the first power member is rotationally connected to the driving wheel, the driving wheel is rotationally connected to the driven wheel by means of intermediate wheels, and the driven wheel is meshed with a gear rack on the other side of the connection plate.

In some embodiments, the movable base is provided with a first electromagnetic attraction plate component in a direction facing the inner wall of the gate slot, a fixed base is fixedly provided at one end of the connection plate away from the movable base, and the fixed base is provided with a second electromagnetic attraction plate component in a direction facing the inner wall of the gate slot.

In some embodiments, the frame further comprises transverse braces, the transverse braces are fixedly connected to the vertical braces, and the transverse braces are provided with a camera.

In some embodiments, the horizontal sensor comprises a pedestal, a middle contact ball arranged in the pedestal, and several contacts arranged on an inner wall of the pedestal, the middle contact ball is connected to the pedestal by means of a conductive wire, and the middle contact ball is filled with hydrogen or nitrogen.

In some embodiments, the lower surface of the bottom plate is provided with at least one second power member and at least one obstacle clearing structure, and the lower surface of the bottom plate is provided with at least one sliding rail along the length direction, the second power member is configured to drive the obstacle clearing structure to slide along the sliding rail by means of a shifting chain, the second power member, the obstacle clearing structure and the sliding rail are all arranged in a one-to-one correspondence manner.

In some embodiments, the obstacle clearing structure comprises an obstacle clearing arm and/or a dredging machine, wherein the obstacle clearing arm and/or dredging machine is slidably connected to the sliding rail by means of a shifting base.

In some embodiments, the upper surface of the bottom plate is provided with a sealed cabin and a generator, the controller, a power supply and a signal transceiver are arranged inside the sealed cabin, a surface of the sealed cabin is provided with a control panel, and the generator is connected to the power supply by a wire.

A method of using an underwater cleaning device for a gate slot, wherein a horizontal sensor senses the levelness of a bottom plate in real time in water and transmits the result to a controller, and the controller controls one or more climbing brackets to move up and down along the gate slot to adjust the levelness of the bottom plate.

In some embodiments, the method of using an underwater cleaning device for a gate slot comprises the following steps:.

The technical solutions of the present invention have the following advantages:.

In order to illustrate technical solutions in specific embodiments of the present invention or in the prior art more clearly, drawings that need to be used in the description of the specific embodiments or the prior art are briefly introduced hereinafter. Apparently, the drawings described below are just some embodiments of the present invention. And for a person with ordinary skill in the art, other drawings can be obtained according to these drawings without expenditure of creative labor.

Reference signs in the drawings are listed as follows: <NUM>. gate slot; <NUM>. climbing bracket; <NUM>. connection rod; <NUM>. transverse brace; <NUM>. bottom plate; <NUM>. sealed cabin; <NUM>. horizontal sensor; <NUM>. second power member; <NUM>. generator; <NUM>. camera; <NUM>. dredging machine; <NUM>. obstacle clearing arm; <NUM>. shifting base; <NUM>. shifting chain; <NUM>. vertical brace; <NUM>. sliding rail; <NUM>. connection plate; <NUM>. first power member; <NUM>. movable base; <NUM>. fixed seat; <NUM>. driving wheel; <NUM>. driven wheel; <NUM>. first electromagnetic attraction plate component; <NUM>. second electromagnetic attraction plate component; <NUM>. pedestal; <NUM>. contact; <NUM>. middle contact ball.

The technical solutions of the present invention will be described clearly and completely with reference to the drawings. Apparently, the described embodiments are some embodiments of the present invention, rather than all of the embodiments. Based on the embodiments described in the present invention, all other embodiments obtainable by a person with ordinary skilled in the art without expenditure of creative labor shall fall within the protection scope of the present invention.

In the description of the present application, it should be noted that terms of "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientation or positional relationships based on the orientation or positional relationships shown in the drawings, and are only intended to facilitate describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation or must be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application. In addition, terms such as "first", "second", "third" are only used for descriptive purpose and cannot be understood as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless explicitly specified and defined otherwise, terms of "mounted", "coupled", and "connected" should be understood in a broad sense, for example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection, or an indirect connection via an intermediate medium, or it may be an internal communication between two elements. For a person with ordinary skilled in the art, the specific meanings of the above terms in the present invention may be understood according to specific circumstances.

In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as there is no conflict between each other.

An underwater cleaning device for a gate slot <NUM> is provided and comprises: a frame, wherein the frame comprises a bottom plate <NUM> and vertical braces <NUM> provided at four corners of the bottom plate <NUM>, each vertical brace <NUM> is provided with a climbing structure, and each of the climbing structures is provided with a climbing bracket <NUM>, the climbing brackets <NUM> are fixedly connected to the vertical braces <NUM> by means of connection rods <NUM>, and the climbing brackets <NUM> are configured to be electromagnetically attracted to an inner wall of the gate slot <NUM>; a horizontal sensor <NUM> provided on the bottom plate <NUM>; a controller in communicational connection with the horizontal sensor <NUM> and the climbing brackets <NUM>, wherein, in a state of underwater, the horizontal sensor <NUM> is configured to sense the levelness of the bottom plate <NUM> and transmit the result to the controller in real time, the controller is configured to control the climbing brackets <NUM> to move up and down along the gate slot <NUM> to maintain the bottom plate <NUM> in a horizontal state. When the frame enters underwater, as affected by multiple factors such as water flow, etc., the bottom plate <NUM> is not always in a horizontal state. When the bottom plate <NUM> is tilted, the horizontal sensor senses the tilting degree of the bottom plate <NUM> and transmits the result to the controller, the controller then controls any one or more climbing structures on the vertical braces <NUM> to make climbing bracket(s) <NUM> of the one or more climbing structures move up and down along the gate slot <NUM> to adjust the levelness of the bottom plate <NUM>. After arriving at the corresponding position, the climbing bracket(s) <NUM> is/are electromagnetically attracted to an inner wall of the gate slot <NUM> to fix the apparatus to the gate slot <NUM> to ensure that the apparatus is in a normal operation state so as to achieve ideal sediment cleaning effect. Meanwhile, in case of a large water flow velocity and a deep water depth, there is no need for a diver to enter underwater for inspection or cleaning, so it has the advantages of low danger, high efficiency, and good economic benefits.

A specific implementation way of the underwater cleaning device for a gate slot <NUM>, as shown in <FIG>, comprises: a frame, wherein the frame is provided with a bottom plate <NUM> and vertical braces <NUM> fixedly provided at four corners of the bottom plate <NUM>, each vertical brace <NUM> is connected to a climbing structure by a connection rod, and the climbing structures are configured to be electromagnetically attracted to an inner wall of the gate slot <NUM>.

As shown in <FIG>, the frame is detachably arranged, and the frame consists of a bottom plate <NUM>, vertical braces <NUM>, and transverse braces <NUM>. Wherein, the upper surface of the bottom plate <NUM> is provided with a generator <NUM>, a second power member <NUM>, sealed cabins <NUM>, and a horizontal sensor <NUM>. The lower surface of the bottom plate <NUM> is provided with an obstacle clearing structure, and the frame has a function of supporting the obstacle clearing structure, the second power member <NUM>, the generator <NUM>, and the sealed cabins <NUM>. Specifically, the horizontal sensor <NUM> is an electronic contact sensing type level gauge configured to detect the levelness of the bottom plate <NUM> and the cleaning device. The level gauge is composed of a middle contact ball <NUM> and several contacts <NUM>. Wherein, the middle contact ball <NUM> is made of a light and thin metal, and its spherical body is connected to a pedestal <NUM> by a fine conductive wire. The middle contact ball <NUM> is filled with hydrogen, the hydrogen is lighter than air, so that the middle contact ball <NUM> floats in the air and maintains vertical. When the bottom plate <NUM> is tiled and causes the horizontal sensor <NUM> to be tilted, the middle contact ball <NUM> would come into contact with one contact <NUM> on the peripheral edge and thus conduct electricity, then a deflection indication signal is sent to the control system for adjusting the levelness of the bottom plate <NUM>.

As shown in <FIG>, the climbing structure comprises a climbing bracket <NUM>, a connection plate <NUM> of the climbing bracket <NUM> is fixedly connected to one of the vertical braces <NUM> by means of a connection rod <NUM>. The climbing structure further comprises a movable base <NUM>, a driving wheel <NUM> is provided on the movable base <NUM>, and the driving wheel <NUM> is meshed with a gear rack on one side of the connection plate <NUM>.

By measuring the levelness with the horizontal sensor <NUM>, when the bottom plate <NUM> is tilted, the horizontal sensor <NUM> senses the tilting degree of the bottom plate <NUM> and transmits the sensing result to the controller, and after calculation by the controller, the controller then controls any one or more climbing structures on the vertical braces at four corners of the bottom plate <NUM> according to the calculation result, so as to make climbing bracket(s) <NUM> of the one or more climbing structures move up and down along the gate slot <NUM> to adjust the levelness of the bottom plate <NUM>, thereby ensuring that the apparatus is in a normal operation state.

As shown in <FIG> and <FIG>, the climbing structure further comprises a movable base <NUM> provided at an upper end of the connection plate <NUM>, with a first power member <NUM>, a driving wheel <NUM>, intermediate wheels and a driven wheel <NUM> disposed in the movable base <NUM>, wherein a drive shaft is disposed between the first power member <NUM> and the driving wheel <NUM>, the intermediate wheels are disposed between the driving wheel <NUM> and the driven wheel <NUM>, and the driving wheel <NUM> and the driven wheel <NUM> are respectively arranged on both sides of the connection plate <NUM>. Specifically, the first power member <NUM> comprises a drive motor and a reducer. The driving wheel <NUM>, the driven wheel <NUM> and the intermediate wheels are all gears. The front end of the driving wheel <NUM> is equipped with the first power member <NUM>, while the front end of the driven wheel <NUM> is not equipped with a power member, using one power member for driving is able to ensure the stability and reliability of torque transmission. The drive motor drives the drive shaft to rotate, the drive shaft drives the driving wheel <NUM> to rotate, and the driving wheel <NUM> drives the driven wheel <NUM> to rotate by means of the intermediate wheels. The driving wheel <NUM> and the driven wheel <NUM> are respectively arranged in the movable base <NUM> to be in meshing transmission with the gear racks on two sides of the connection plate <NUM>. It should be noted that the number of the intermediate wheels is <NUM>, so as to ensure that rotation directions of the driving wheel <NUM> and the driven wheel <NUM> are opposite, and ensure that the driving wheel <NUM> and the driven wheel <NUM> of the movable base <NUM> move in an upward or downward direction synchronously on both sides of the connection plate <NUM>. To fix the climbing structure, the movable base <NUM> is provided with a first electromagnetic attraction plate component <NUM> in a direction facing the inner wall of the gate slot <NUM>, a fixed base <NUM> is fixedly provided at one end of the connection plate <NUM> away from the movable base <NUM>. To simplify the motion structure, the fixed base <NUM> is fixedly arranged at a lower end of the connection plate <NUM>, and the fixed base <NUM> is provided with a second electromagnetic attraction plate component <NUM> in a direction facing the inner wall of the gate slot <NUM>. The first electromagnetic attraction plate component <NUM> comprises a first electromagnetic base plate disposed on the movable base <NUM>, and a first electromagnetic plate disposed on the first electromagnetic base plate. The second electromagnetic attraction plate component <NUM> comprises a second electromagnetic base plate disposed on the movable base <NUM>, and an electromagnetic plate disposed on the second electromagnetic base plate. The fixed base <NUM> is arranged at the lower or upper part of the climbing bracket <NUM>, and the movable base <NUM> is arranged on the other side of the climbing bracket <NUM>, and the upper and lower positions of the movable base <NUM> and the fixed base <NUM> can be exchanged.

As shown in <FIG>, the upper surface of the bottom plate <NUM> is further provided with two sealed cabins <NUM>, a power supply, the controller, a signal transceiver, an electric energy frequency-conversion frequency modulator and an energy storage device are arranged inside the sealed cabins <NUM>. The sealed cabins <NUM> are connected to the equipment outside the sealed cabins <NUM> by waterproof joints and cables so as to be able to transmit electrical energy, control instructions and operation data, and the sealed cabins <NUM> are connected to a control room above water by a towed cable. If a diver performs a diving operation along with the frame, the waterproof control panel on the sealed cabins <NUM> can also realize underwater on-site operation.

To clear sediments such as sludge at the bottom of the gate frame, as shown in <FIG>, the lower surface of the bottom plate <NUM> is provided with sliding rails <NUM> along the length direction, each of the sliding rails <NUM> is sleeved with a clamp bracket internally provided with contact rollers, a shifting base <NUM> is connected under the clamp bracket, and an obstacle clearing structure is connected under the shifting base <NUM>. In principle, each obstacle clearing structure is provided on one sliding rail <NUM> separately, so that common rail interference does not occur during operation. The bottom plate <NUM> is provided with second power members <NUM>, the second power members <NUM> may be a plurality of sets of driving mechanisms, and in principle, each set of the second power members <NUM> drives one obstacle clearing structure separately, that is, the second power member <NUM>, the obstacle clearing structure and the sliding rail <NUM> are all arranged in a one-to-one correspondence manner. Specifically, the second power member <NUM> comprises a walking motor and a reducer gearbox. The obstacle clearing structure comprises an obstacle clearing arm <NUM> and a dredging machine <NUM>, wherein the obstacle clearing structure is moved by the second power member <NUM> and a driving gear through a shifting chain <NUM>, thereby driving the obstacle clearing arm <NUM> and the dredging machine <NUM> to move by means of the clamp bracket and the shifting base attached thereto. The obstacle clearing arm <NUM> and the dredging machine <NUM> are slidably connected to the sliding rails <NUM> by the shifting bases <NUM>, and each of the shifting bases <NUM> is preferably installed in an embedded manner in cooperation with the rail to make each of the shifting bases <NUM> move back and forth on the rail. According to the number of the obstacle clearing structures, a single-rail or multi-rail arrangement form may be used.

As shown in <FIG> and <FIG>, a generator <NUM> is further arranged on the frame to supply power for the entire device. The generator <NUM> is connected to the electric energy frequency-conversion frequency modulator, the energy storage device and the power supply inside the sealed cabins <NUM> by wires.

As shown in <FIG>, cameras <NUM> are arranged upon the transverse braces <NUM>, and also at an end part of the obstacle clearing arm <NUM> and at an end part of the dredging machine <NUM>. The cameras <NUM> have functions such as pan-tilt-zoom (PTZ), light supplement and night vision, thereby facilitating timely tracking and omnidirectional observation, and facilitating observation in an environment with poor water quality and poor lighting. One of the cameras <NUM> is arranged upon the transverse braces <NUM> to generally observe the surrounding environment in a state of underwater. And some of the cameras <NUM> are arranged at the end part of the obstacle clearing arm <NUM> and at the end part of the dredging machine <NUM> to observe the local environment accurately during working for performing precise operation. Signal collected by the cameras <NUM> is transmitted to the controller in the sealed cabin <NUM> in a wired manner, and after signal processing by the controller, and then the result is transmitted to the control room above the water surface in a wired manner. The instructions sent by the control room are transmitted in a wired manner to ensure the stability of signal transmission. After a video signal collected by the cameras <NUM> is transmitted to the controller inside the sealed cabins <NUM> or a control console in the control room, video information recognition and analysis is performed by a built-in control software, and automatic recognition, automatic judgement and automatic operation are performed according to work tasks pre-built by personnel, so that the operation mode is simplified, the continuity and reliability of the operation are ensured, and the intelligent level is effectively improved.

It should be noted that the device of the present patent application may adopt two control modes including a remote master control mode and an on-site control mode, as well as two control manners including an automatic control manner and a manual control manner. That is, the control system is divided into a master control device arranged above the water surface and an on-site control device arranged inside the sealed cabins <NUM>. The master control device above the water surface is mainly used for overall control, timely observation, real-time recording and analysis of data and information by an operator with the device of the present patent application. And the master control device may also perform automatic control under the control of a program. The on-site control device is mainly used for automatic control, and may also be on-site controlled by an operator who has followed the detection platform to enter underwater when needed.

During the specific implementation process, according to the structure of the gate slot <NUM>, standard interchangeable transverse braces <NUM> or vertical braces <NUM> are selected for assembling at will, so as to assemble the braces into frames have different lengths and widths for inspection of gate slots <NUM> with different dimensions. After the assembly of the frame and the climbing structures, the generator <NUM>, etc. installed on the frame is completed, the entire apparatus is first moved to the position at the orifice of the gate slot <NUM>, the energy storage device inside the sealed cabins <NUM> is used for supplying power. After being powered on, the movable base <NUM> or the fixed base <NUM> is electromagnetically attracted to or separated from the steel structural members of the gate slot <NUM>, and movement thereof is carried out by synchronous stepwise motions of the movable base <NUM> and the fixed base <NUM>. Namely, when the movable base <NUM> is attracted to and fixed on the gate slot <NUM>, the fixed base <NUM> is separated from the gate slot <NUM> at the same time; or, when the movable base <NUM> is separated from the gate slot <NUM>, the fixed base <NUM> is attracted to and fixed on the gate slot <NUM> at the same time, and in combination with the driving by the first power member <NUM> via the meshing of gears and gear racks, gradual descension from the orifice of the gate slot <NUM> is realized. The horizontal sensor <NUM> on the bottom plate <NUM> is connected to the sealed cabins <NUM> in a wired manner. If a deviation of levelness is detected during the movement or the working process, the middle contact ball <NUM> of the level gauge comes into contact with one peripheral contact point <NUM>, then a signal is transmitted to the controller inside the sealed cabin <NUM>, and the controller sends the signal to the master control room. After receiving the signal, the console in the control room judges whether the deviation exceeds a tolerance range. If the deviation does not exceed the tolerance range, no deviation adjustment will be made, and if the deviation exceeds the tolerance range, adjustment will be made. During the adjustment process, respective climbing brackets <NUM> are integrally coordinated and controlled, that is, when movement of the climbing brackets <NUM> on the opposite side is stopped, the climbing brackets <NUM> on the lower side is slightly lifted at the same time, that is, the first power member <NUM> drives the driving wheel <NUM> and the driven wheel <NUM> to rotate, so that the connection plate <NUM> moves upwards and drives the bottom plate <NUM> on the lower side to move upwards until the levelness of the bottom plate <NUM> is adjusted to a reasonable range.

In a state of underwater, the second power members <NUM> drive the obstacle clearing arm <NUM> and the dredging machine <NUM> to move. The obstacle clearing arm <NUM> and the dredging machine <NUM> are able to perform multi-dimensional movement and rotation to inspect a vertical surface and a bottom sill surface of the gate slot <NUM>. A manipulator of the obstacle clearing arm <NUM> clamps and clears large block-shaped debris, the large block-shaped debris cleared by the obstacle clearing arm <NUM> can be took away from an area of the gate slot <NUM> by water flow, or the large block-shaped debris can be clamped and put into the frame by the obstacle clearing arm <NUM>, and after the cleaning is completed, the large block-shaped debris is brought out of the water surface by the frame for inspection and analysis. A base of the manipulator is connected to the obstacle clearing arm <NUM> by rotational sleeving. The dredging machine <NUM> is configured to flush and clean loose silt and other sediments. When it is necessary to flush and clamp the sediments simultaneously, the obstacle clearing arm <NUM> and the dredging machine <NUM> may work together cooperatively for cleaning. At this time, the cameras <NUM> installed on the obstacle clearing arm <NUM> and the dredging machine <NUM> capture images under the control of a program in the controller, and the captured images are automatically recognized by the program. And with the image capturing and recognition program internally provided in the controller, points are taken from the contour of the image captured by the cameras to compare the acquired image contour with a built-in image from an image library for determination, so that the characteristics, the number and the volume of the sediments in the gate slot <NUM> are reasonably recognized and judged, even under a condition that the underwater water quality is turbid, so that cleaning is facilitated, and cleaning by automatic grabbing or flushing can be performed under programmed control. It should be noted that, when underwater fine cleaning or measurement is needed, on-site personnel can enter underwater by staying in the frame for operation, and the frame can also serve as a loading platform for underwater transportation of objects. After completing the cleaning, according to a reverse operation of the above-described descension procedure, the frame is lifted to the orifice of the gate slot <NUM> to complete the operation.

The underwater cleaning device for a gate slot <NUM> provided by the present invention has the following advantages: (<NUM>) the present patent application has a simple structure and strong adaptability. It can adapt to situations with a large water depth and a high flow rate, and can be used for underwater operation in an unmanned manner or a manned manner. By means of combining standard components, the frame can meet the maintenance needs of various orifice dimensions. It not only can be used for situations of underwater operations, but also can be used for various situations of other hole and groove operations above water; (<NUM>) there are various forms of underwater operations that can be undertaken by the device. It can be applied to various underwater dredging situations, as well as various working conditions and needs such as underwater welding, measurement, repair, drilling hole, spraying, etc. It can also meet the needs of goods transportation with rapid and accurate movement up and down with objects loaded thereon, and can also meet various operation forms, and covers various needs of underwater construction; (<NUM>) innovation of the device is strong, by using innovative apparatuses such as electromagnetic attraction climbing brackets <NUM>, an electronic contact sensing type level gauge, an assembled frame, exchangeable obstacle clearing structures, underwater self-powered units, and underwater on-site control units, etc. The electromagnetic attraction climbing brackets <NUM> have a simple and reliable structure and are very reliable and flexible. The electronic contact sensing type level gauge has high sensitivity and strong reliability, and can meet the real-time adjustment needs of the system.

As an alternative implementation way, the manipulator of the obstacle clearing arm <NUM> can also be an electric drill, a scraper, a spraying gun, etc. to perform refined and complex operations. Other than using the equipped manipulator of the obstacle clearing arm <NUM> for grabbing and clearing debris, the manipulator, which is preferably connected to the obstacle clearing arm <NUM> by means of rotational sleeving or snap-fitting, can also be replaced with professional repair tools such as an electric drill, a welding gun, a scraper, and a spraying gun for various refined and complex underwater operations.

As an alternative implementation way, the plurality of obstacle clearing structures can also be arranged in a common rail manner. The obstacle clearing structure may also adopt a slidable manner without using a sliding rail, such as by using a clamping slot.

As an alternative implementation way, the obstacle clearing structure may also adopt other movement traction manners such as being pulled by a steel wire rope.

As an alternative implementation way, the number of the intermediate wheels can also be another even number such as <NUM> or <NUM>.

As an alternative implementation way, the number of the sealed cabins <NUM> can also be <NUM>, <NUM>, <NUM>, or even more.

As an alternative implementation way, the middle contact ball <NUM> is filled with nitrogen or any other gas with a density lower than air.

Claim 1:
An underwater cleaning device for a gate slot, characterized in comprising:
a frame, wherein the frame comprises a bottom plate (<NUM>) and vertical braces (<NUM>) provided at four corners of the bottom plate (<NUM>), each vertical brace (<NUM>) is provided with a climbing structure, and each of the climbing structures is provided with a climbing bracket (<NUM>), the climbing brackets (<NUM>) are fixedly connected to the vertical braces (<NUM>) by means of connection rods (<NUM>), and the climbing brackets (<NUM>) are configured to be electromagnetically attracted to an inner wall of the gate slot (<NUM>);
a horizontal sensor (<NUM>) provided on the bottom plate (<NUM>);
a controller in communicational connection with the horizontal sensor (<NUM>) and the climbing brackets (<NUM>), wherein, in a state of underwater, the horizontal sensor (<NUM>) is configured to sense the levelness of the bottom plate (<NUM>) and transmit the result to the controller in real time, the controller is configured to control the climbing brackets (<NUM>) to move up and down along the gate slot (<NUM>) to maintain the bottom plate (<NUM>) in a horizontal state.