Net cage netting cleaning device with mechanical rotating disc coupled with high-pressure water jet

Abstract

The net cage netting cleaning device comprises a support, a cleaning disc is arranged at the bottom of the support, the cleaning disc is rotationally connected with the support through a rotating shaft, a plurality of cleaning blades are arranged on the bottom face of the cleaning disc, and the cleaning blades are elastically connected with the cleaning disc. A cleaning nozzle is arranged at the bottom of the cleaning disc, the cleaning nozzle is rotationally connected with the cleaning disc through a universal joint, the cleaning nozzle is connected with a high-pressure water pipe through a rotating joint, and the rotating joint and the rotating shaft are coaxially arranged. A mechanical and high-pressure water jet coupling method is adopted, the cleaning efficiency of shellfish attachments is improved, the labor cost is greatly reduced in the whole cleaning process, the good cleaning effect is achieved through repeated rotation of the cleaning disc, the cleaning efficiency of the net cage is effectively improved, damage and pollution to the ecological environment are reduced, and the overall structure is simple and reliable.

Description

[0001] This application is a divisional application of the invention patent application with the application date of November 8, 2022, application number 202211391131.8, and invention name "A cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet". Technical Field

[0002] The present invention relates to the technical field of aquaculture equipment, and in particular to a cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet. Background Art

[0003] Cage aquaculture is one of China's main marine aquaculture methods. According to statistics, as of the end of 2021, the country's marine aquaculture area reached 2.0255 million hectares. Of this, conventional cage aquaculture accounted for 37.8304 million square meters, and deep-water cage aquaculture accounted for 38.2139 million square meters. China's total marine aquaculture fish production reached 22.1114 million tons, of which 963,900 tons came from cage aquaculture, accounting for 4.36% of the country's total. Marine cage aquaculture has gradually become the mainstay of China's marine fish aquaculture. Since the 1980s, my country's marine cage aquaculture has experienced significant development, with both aquaculture area and production increasing annually. Marine cage aquaculture is practiced in all coastal provinces and municipalities except Hebei, Tianjin, and Shanghai. Marine cage aquaculture is evolving from traditional small-scale cage aquaculture to offshore deep-water cage aquaculture and large-scale deep-sea cage aquaculture.

[0004] With the rapid development of marine cage aquaculture, the workload for cage cleaning is increasing. Currently, cage cleaning in my country relies primarily on manual labor and high-pressure jet cleaning. Manual cleaning is inefficient, labor-intensive, and expensive, and the waste generated during the cleaning process is difficult to dispose of. Furthermore, net changing operations can affect the growth of aquaculture organisms. High-pressure jet cleaning is difficult to remove from clams, barnacles, and other attachments, severely restricting the development of the cage aquaculture industry and significantly impacting its economic benefits.

[0005] Commercialized cleaning equipment has been in industrial use for many years, and countries like Norway and Japan have developed mature underwater cage cleaning equipment. However, due to varying water quality in aquaculture areas, the attachments to cages in countries like Norway and Japan are primarily algae, which have low adhesion strength and are easy to clean. In contrast, in my country, attachments to cages are primarily shellfish such as blue mussels and oysters, which reproduce extremely rapidly, greatly increasing the difficulty of cleaning. Therefore, imported cleaning equipment is ineffective for effectively cleaning cages in my country and is also expensive. Currently, China relies primarily on manual net washing, and cleaning a typical cylindrical cage with a diameter of 50 meters and a height of 50 meters takes approximately two to three months.

[0006] Mechanized cleaning technology has not been well applied in my country. Designing and using an efficient mechanized cage cleaning device is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0007] In response to the above problems, the present invention provides a cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet. It adopts a method of coupling mechanical and high-pressure water jets to improve the cleaning efficiency of shellfish attachments, greatly reducing labor costs during the entire cleaning process. Through the repeated rotation of the cleaning disc, a good cleaning effect is achieved, effectively improving the cleaning efficiency of the cage, reducing damage and pollution to the ecological environment, and the overall structure is simple and reliable.

[0008] The technical solution of the present invention is a cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet, comprising a bracket, a cleaning disc provided at the bottom of the bracket, the cleaning disc being rotatably connected to the bracket via a rotating shaft, a plurality of cleaning blades provided on the bottom of the cleaning disc, the cleaning blades being elastically connected to the cleaning disc, a cleaning nozzle provided at the bottom of the cleaning disc, the cleaning nozzle being rotatably connected to the cleaning disc via a universal joint, the cleaning nozzle being connected to a high-pressure water pipe via a rotary joint, and the rotary joint being coaxially arranged with the rotating shaft.

[0009] Furthermore, there are multiple cleaning trays, and the multiple cleaning trays are evenly arranged at the bottom of the bracket.

[0010] Furthermore, there are multiple cleaning nozzles, and the multiple cleaning nozzles are evenly arranged at the bottom of the cleaning tray.

[0011] Furthermore, the cleaning blade is elastically connected to the cleaning disc via a spring, and the rotating shaft is dynamically connected to a waterproof motor.

[0012] Furthermore, it also includes a frame, the cleaning tray is installed on one side of the frame through a bracket, and a protective net is installed on the frame.

[0013] Furthermore, a bottom plate is provided on one side of the frame, and the cleaning tray is installed in a cleaning opening of the bottom plate, and the cleaning tray and the bottom plate are located on the same plane.

[0014] Furthermore, a walking mechanism is installed on the frames on the left and right sides of the base plate, and the bottom of the walking mechanism and the base plate are located on the same plane.

[0015] Furthermore, the walking mechanism is a crawler track or a rubber wheel.

[0016] Furthermore, a walking propeller assembly and a steering propeller assembly are installed on the frame.

[0017] Furthermore, a first propeller is installed on the frame on the adjacent side of the base plate, and the first propeller is located between the two walking mechanisms. A second propeller and a third propeller are installed on the frame on the opposite side of the first propeller, and the second propeller and the third propeller are arranged opposite to each other. A fourth propeller and a fifth propeller are installed on the frame on the opposite side of the base plate, and the fourth propeller and the fifth propeller are arranged opposite to each other. A sixth propeller and a seventh propeller are installed on the frame on the walking mechanism side, and the sixth propeller and the seventh propeller are arranged opposite to each other. The first propeller, the second propeller, the third propeller, the fourth propeller, the fifth propeller, the sixth propeller, and the seventh propeller are all connected to a waterproof motor.

[0018] Furthermore, a camera and a lighting lamp are installed on the frame on the bottom plate side.

[0019] Furthermore, a sewage suction port is provided on the bottom plate, and the sewage suction port is connected to a suction pump through a pipeline.

[0020] The beneficial effects of the present invention are:

[0021] 1. The system uses a mechanical coupling method with high-pressure water jets. High-pressure water is sprayed from the cleaning nozzle to drive the cleaning disc to rotate. At the same time, the high-pressure water from the cleaning nozzle and the cleaning blades act simultaneously on the dirt on the net cage, removing the dirt from the net cage and achieving the purpose of cleaning the net cage. The cleaning blades and the cleaning disc are elastically connected, which neither scratches the net cage nor effectively removes attachments such as shellfish. This greatly reduces labor costs during the entire cleaning process. The repeated rotation of the cleaning disc achieves a good cleaning effect, further effectively improving the cleaning efficiency of the net cage. The cleaning speed can reach 600 square meters per hour, and a net washing operation can be completed in only about 13 hours, greatly improving operational efficiency.

[0022] 2. The current manual cleaning requires the cages to be placed on the coast for cleaning. After cleaning, the coast will have a foul odor and cause serious environmental pollution. The device of the present invention can directly clean the cages efficiently on the cage platform without the need for cleaning on the shore, significantly reducing the damage and pollution to the ecological environment. The overall structure is simple and reliable.

[0023] 3. The cleaning device of the present invention can be used alone or in combination with multiple cleaning discs. It can also be used in conjunction with a propeller. It has various usage modes and is suitable for cleaning cages of different specifications and sizes.

[0024] 4. The cooperation between the cleaning plate and the sewage suction port on the bottom plate enables the dirt cleaned by the cleaning plate to be extracted through the sewage suction port and discharged centrally, making it more convenient to handle the dirt. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the three-dimensional structure of the first embodiment of the present invention;

[0026] Figure 2 Schematic diagram of the three-dimensional structure of the cleaning plate of the present invention;

[0027] Figure 3 This is a front view of the structure of the cleaning disk of the present invention;

[0028] Figure 4 This is a schematic diagram of the operation of the first embodiment of the present invention;

[0029] Figure 5 Schematic diagrams of three structures of cleaning blades in the present invention;

[0030] Figure 6 This is a schematic diagram of the three-dimensional structure of the second embodiment of the present invention;

[0031] Figure 7 This is a front view of the structure of the second embodiment of the present invention;

[0032] Figure 8 This is a schematic diagram of the operation of the second embodiment of the present invention;

[0033] Figure 9 is a schematic diagram of the three-dimensional structure of a third embodiment of the present invention;

[0034] Figure 10 This is a front view of the structure of the third embodiment of the present invention;

[0035] Figure 11 This is a schematic diagram of the operation of the third embodiment of the present invention;

[0036] In the figure: 1. Bracket; 2. Cleaning disc; 3. Rotating shaft; 4. Cleaning blade; 5. Nozzle; 6. High-pressure water pipe; 7. Frame; 8. Protective net; 9. Bottom plate; 10. Walking mechanism; 11. First propeller; 12. Second propeller; 13. Third propeller; 14. Fourth propeller; 15. Fifth propeller; 16. Sixth propeller; 17. Seventh propeller; 18. Underwater ultra-clear camera; 19. LED lighting; 20. Sewage suction port. DETAILED DESCRIPTION

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0039] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0040] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when in use. These are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0041] Furthermore, the terms “first”, “second”, etc. are merely used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0042] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0043] Example 1: Figure 1-5 As shown, the present invention provides a cage net cleaning device that uses a mechanical turntable coupled with a high-pressure water jet, comprising a bracket 1, a cleaning disc 2 disposed at the bottom of the bracket 1, the cleaning disc 2 being rotatably connected to the bracket 1 via a rotating shaft 3, a plurality of cleaning blades 4 disposed on the bottom of the cleaning disc 2, the cleaning blades 4 being elastically connected to the cleaning disc 2, a cleaning nozzle 5 disposed at the bottom of the cleaning disc 2, the cleaning nozzle 5 being rotatably connected to the cleaning disc 2 via a universal joint, and a high-pressure water pipe 6 connected to the cleaning nozzle 5 via a rotary joint, the rotary joint being coaxial with the rotating shaft 3. Because the cleaning nozzle 5 needs to rotate with the cleaning disc 2, a rotary joint is required to connect the cleaning nozzle 5 and the high-pressure water pipe 6. The rotary joint is an existing component, such as the SHGY-8 rotary joint.

[0044] The cleaning blade 4 is elastically connected to the cleaning disc 2 through a spring, and the rotating shaft 3 is powered by a waterproof motor. The waterproof motor can also drive the cleaning disc 2 to rotate, so the cleaning disc 2 can be driven to rotate by the cleaning nozzle 5, or it can be driven to rotate by the cleaning waterproof motor. The cleaning disc 2 is elastically connected to the cleaning blade 4 to prevent the net from being hooked, cutting the net box, and damaging the net box. In addition to the spring, the elastic connection between the cleaning disc 2 and the cleaning blade 4 can also be connected by a rubber sheet. The rubber sheet also has a certain elasticity and can also avoid seawater erosion. It has good rust resistance and increases the service life of the connection position. There are multiple cleaning nozzles 5, and the multiple cleaning nozzles 5 are evenly arranged at the bottom of the cleaning disc 2 to ensure the smooth rotation of the cleaning disc. The cleaning nozzle 5 is rotatably connected to the cleaning disc 2 via a universal joint, meaning the angle between the cleaning nozzle 5 and the cleaning disc 2 is adjustable. During use, the cleaning nozzle 5 is generally parallel to the tangent of the cleaning disc 2 or at an angle less than 90 degrees to the tangent. The cleaning nozzles 5 are arranged clockwise or counterclockwise around the perimeter, allowing the high-pressure water ejected from the cleaning nozzles 5 to repeatedly rotate the cleaning disc 2. During cleaning, the cleaning disc 2 is parallel to the mesh of the cage. This allows the angle between the cleaning nozzle 5 and the mesh to be adjusted as needed, allowing the high-pressure water ejected from the cleaning nozzle 5 to better impact dirt attached to the mesh, making cleaning more convenient and quicker. The universal joint allows the angle between the cleaning nozzle 5 and the cleaning disc 2 to be adjustable. The universal joint can be hollow, allowing the high-pressure water to flow directly through the joint to the cleaning nozzle 5 before being ejected. Alternatively, the universal joint can be an adjustable ball joint, solely responsible for adjusting the angle between the cleaning nozzle 5 and the cleaning disc 2. These universal joints are all conventional existing parts, such as the 36275 series adjustable ball joints.

[0045] The cleaning device for a single cleaning tray 2 is typically operated by a diver, with the high-pressure water pipe 6 connected to a high-pressure water pump on board. The pressure and volume of the high-pressure water sprayed from the cleaning nozzle 5 can be adjusted by the high-pressure water pump, for example by increasing the flow rate and reducing the pressure to minimize damage to the cages.

[0046] like Figure 5 As shown, the cleaning blades 4 can be constructed in a variety of ways, including two symmetrical outer arcs, a combination of an outer arc and an inner arc, or a combination of an arc edge and a straight edge, to accommodate different net structures and net rope diameters. The cleaning blades 4 are unopened, blunt blades to prevent damage to the net cage. During rotation, the cleaning device uses the cleaning blades 4 to strike shellfish debris, breaking it and dislodging it. The cleaning blades 4 are elastically connected, providing better control of force, enabling the cleaning of shellfish without damaging the net cage. Circumferential and radial distribution of the blades is optimal.

[0047] Example 2: Figure 6-8As shown, based on the first embodiment, multiple cleaning trays 2 are provided, evenly arranged at the bottom of the bracket 1. These multiple cleaning trays 2 are located on the same plane. During use, the cleaning trays 2 are parallel to the net being cleaned. A high-pressure water pipe 6 is connected to a high-pressure water pump on board. Simply pulling the bracket 1 up and down or left and right with a rope brings the cleaning device closer to the net to clean it. This makes it easy to use and has a simple and reliable structure.

[0048] Example 3: Figure 9-11 As shown, based on the first embodiment, a frame 7 is further included. The cleaning tray 2 is mounted on one side of the frame 7 via a bracket 1. A protective net 8 is mounted on the frame 7. The size of the protective net 8 can be changed according to the type and size of the cultured organisms to prevent the cultured organisms from entering the frame 7 and causing damage to the cultured organisms.

[0049] A base plate 9 is provided on one side of the frame 7. The cleaning tray 2 is mounted within a cleaning port on the base plate 9, with the cleaning tray 2 and base plate 9 being coplanar. Typically, two cleaning trays 2 are mounted on the base plate 9. A sewage suction port 20 is provided on the base plate 9, which is connected to a suction pump via a pipe. During operation, the base plate 9 is positioned parallel to the netting to be cleaned. The cleaning blades on the cleaning tray 2 come into contact with dirt attached to the netting, cleaning it. The dirt is then sucked away by the sewage suction port 20 and transported to a vessel or shore for centralized disposal.

[0050] A running mechanism 10 is mounted on the frames 7 on the left and right sides of the base plate 9. The bottom of the running mechanism 10 is flush with the base plate 9. The running mechanism 10 can be a track or rubber wheel, and the choice can be based on the mesh size and material of the netting. The running mechanism 10 facilitates the movement of the entire cleaning device. The running mechanism 10 can be driven by a waterproof motor or a propeller.

[0051] A walking propeller assembly and a steering propeller assembly are installed on the frame 7. Specifically: a first propeller 11 is installed on the frame 7 on the adjacent side of the base plate 9, and the first propeller 11 is located between the two walking mechanisms 10. A second propeller 12 and a third propeller 13 are installed on the frame 7 on the opposite side of the first propeller 11, and the second propeller 12 is arranged opposite to the third propeller 13. A fourth propeller 14 and a fifth propeller 15 are installed on the frame 7 on the opposite side of the base plate 9, and the fourth propeller 14 is arranged opposite to the fifth propeller 15. A sixth propeller 16 and a seventh propeller 17 are installed on the frame 7 on the side of the walking mechanism 10, and the sixth propeller 16 is arranged opposite to the seventh propeller 17. The first propeller 11, the second propeller 12, the third propeller 13, the fourth propeller 14, the fifth propeller 15, the sixth propeller 16, and the seventh propeller 17 are all connected to a waterproof motor. That is, the first propeller 11, the second propeller 12, and the third propeller 13 provide propulsion for the cleaning device, allowing it to move on the cage net; the fourth propeller 14 and the fifth propeller 15 provide vertical force for the cleaning device, allowing the cleaning disc 2 of the cleaning device to fit closely with the cage net, facilitating cleaning; the sixth propeller 16 and the seventh propeller 17 provide steering force for the cleaning device, facilitating steering. The first propeller 11, the second propeller 12, the third propeller 13, the fourth propeller 14, and the fifth propeller 15 are the propeller assembly for propulsion; the sixth propeller 16 and the seventh propeller 17 are the propeller assembly for steering. The first propeller 11, the second propeller 12, the third propeller 13, the fourth propeller 14, the fifth propeller 15, the sixth propeller 16, and the seventh propeller 17 are all equipped with protective covers on the outside to prevent farmed organisms from entering the propellers, causing damage to the propellers and harming the farmed organisms.

[0052] The frame on the bottom plate side is mounted with a camera and a lighting fixture. Specifically, the frame 7 on the bottom plate 9 side is mounted with an underwater high-definition camera 18 and an LED lighting fixture 19. The synergistic effect of the underwater high-definition camera 18 and the LED lighting fixture 19 facilitates observation of the types of fouling organisms attached to the net, regulates the rotation speed and travel speed of the cleaning disc 2, and allows for monitoring whether the net has achieved the desired cleaning effect and whether multiple cleaning passes are necessary.

[0053] During use, the high-pressure water pipe 6 is connected to the high-pressure water pump on the boat. The crawler tracks fit the net and the net is moved. At the same time, the generator or battery on the boat provides energy for the waterproof motor.

[0054] The present invention adopts a method of coupling mechanical and high-pressure water jets. High-pressure water is sprayed through the cleaning nozzle 5 to drive the cleaning disc 2 to rotate. At the same time, the high-pressure water sprayed by the cleaning nozzle 5 and the cleaning blade 4 act on the dirt in the mesh cage at the same time, so that the dirt on the mesh cage falls off, thereby achieving the purpose of cleaning the mesh cage. The labor cost is greatly reduced in the entire cleaning process. The repeated rotation of the cleaning disc 2 achieves a good cleaning effect, effectively improves the cleaning efficiency of the mesh cage, reduces damage and pollution to the ecological environment, and has a simple and reliable overall structure. The cleaning device of the present invention can be used alone or in combination with multiple cleaning discs 2. It can also be used in conjunction with a propeller. It has various usage methods and is suitable for cleaning mesh cages of different specifications and sizes. The cleaning disc 2 cooperates with the sewage suction port 20 on the bottom plate 9, so that the dirt cleaned by the cleaning disc 2 can be extracted through the sewage suction port 20 and then discharged in a centralized manner, which is more convenient for the treatment of dirt.

[0055] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet, characterized by: The invention comprises a bracket (1), a cleaning disc (2) is provided at the bottom of the bracket (1), the cleaning disc (2) is rotatably connected to the bracket (1) via a rotating shaft (3), a plurality of cleaning blades (4) are provided on the bottom surface of the cleaning disc (2), the cleaning blades (4) are elastically connected to the cleaning disc (2), a cleaning nozzle (5) is provided at the bottom of the cleaning disc (2), the cleaning nozzle (5) is rotatably connected to the cleaning disc (2) via a universal joint, the cleaning nozzle (5) is connected to a high-pressure water pipe (6) via a rotating joint, and the rotating joint is coaxially arranged with the rotating shaft (3).

2. The cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet according to claim 1 is characterized in that: There are a plurality of cleaning discs (2), and the plurality of cleaning discs (2) are evenly arranged at the bottom of the bracket (1); there are a plurality of cleaning nozzles (5), and the plurality of cleaning nozzles (5) are evenly arranged at the bottom of the cleaning disc (2).

3. The cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet according to claim 1 is characterized in that: The cleaning blade (4) is elastically connected to the cleaning disc (2) via a spring, and the rotating shaft (3) is dynamically connected to a waterproof motor.

4. The cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet according to claim 1 is characterized in that: It also includes a frame (7), the cleaning disc (2) is installed on one side of the frame (7) through a bracket (1), and a protective net (8) is installed on the frame (7).

5. The cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet according to claim 4 is characterized in that: A bottom plate (9) is provided on one side of the frame (7), and the cleaning tray (2) is installed in a cleaning opening of the bottom plate (9), and the cleaning tray (2) and the bottom plate (9) are located on the same plane; Preferably, a walking mechanism (10) is installed on the frames (7) on the left and right sides of the base plate (9), and the bottom of the walking mechanism (10) and the base plate (9) are located on the same plane.

6. The cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet according to claim 5, characterized in that: The walking mechanism (10) is a crawler track or a rubber wheel.

7. The cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet according to claim 5, characterized in that: A walking propeller assembly and a steering propeller assembly are installed on the frame (7).

8. The cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet according to claim 5, characterized in that: A camera and a lighting lamp are installed on the frame (7) on the side of the base plate (9).

9. The cage net cleaning device with a mechanical turntable coupled with a high-pressure water jet according to claim 5, characterized in that: A sewage suction port (20) is provided on the bottom plate (9), and the sewage suction port (20) is connected to a suction pump via a pipeline.

10. An underwater walking device, comprising: Framework (7), A walking mechanism (10) is mounted on opposite sides of the frame (7); The propeller assembly, including a traveling propeller assembly and a steering propeller assembly, is mounted on the side wall of the frame (7).

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