A sealing structure for a trawl net plate water layer adjustment mechanism

Abstract

This invention relates to a sealing structure for a water layer adjustment mechanism for a trawl net. A first waterproof sealed chamber is formed by a sealed connection between a cover plate and the water layer adjustment mechanism, and the entrance to a second waterproof sealed chamber is located inside the first waterproof sealed chamber. Simultaneously, guide rails located within the water layer adjustment mechanism and slide rails on both sides of the external water layer adjustment mechanism together form an I-shaped stabilizing structure, providing tensile strength. A low-friction pad is provided on the top surface of the water layer adjustment mechanism to provide compressive strength, reducing the impact of reciprocating water pressure when the mechanism is used to adjust the net's posture.

Description

Technical Field

[0001] This invention belongs to the field of underwater sealing technology, and in particular relates to a sealing structure for a trawl net plate water layer adjustment mechanism. Background Technology

[0002] Existing trawl nets used for Antarctic krill harvesting have two sides connected to the forked plates of the net by towing chains. The towing plates of the net are equipped with towing pull plates, which are connected to the traction system of the fishing vessel through the towing lines. The fishing vessel steers the net to achieve a balanced posture in the water, causing the net opening to expand horizontally and towing the net for sweeping harvesting.

[0003] To adjust the relative position of the towing line fixing point and the net during fishing operations, thereby changing the underwater attitude of the net and adjusting the water layer for trawl operations, the inventors have designed a water layer adjustment mechanism and method for Antarctic krill trawl nets (publication number CN111990346A). The aforementioned invention uses a water layer adjustment mechanism installed on the net for bidirectional control of the raising and lowering of the towing line connecting block. A controller dynamically controls the operation of the water layer adjustment mechanism, enabling dynamic control of the position of the connection point between the towing line and the net in the height direction of the net. This allows for dynamic adjustment of the net's attitude in the water to achieve equilibrium during fishing.

[0004] Several problems were found in the use of the aforementioned invention. The screw, slider, guide rail, and mounting bracket used to adjust the position of the traction cable connecting block are all exposed to seawater, making them susceptible to corrosion from seawater over time. Furthermore, the screw, slider, and guide rail, which face the seawater, are precision machinery, yet lack a front bumper, making them vulnerable to collisions with marine debris and subsequent damage. Therefore, it is necessary to seal and protect the entire water level adjustment mechanism. Typically, this can be achieved simply by installing a cover plate on the front of the mounting bracket and sealing it with a sealing ring.

[0005] However, unlike conventional sealing methods, the sealing of variable water level regulation mechanisms presents the following challenges:

[0006] 1. The water level adjustment mechanism is underwater and will be subjected to huge water pressure during its journey. All of the water pressure will be applied to the cover plate. The tow rope connecting block, which is a movable part, will also be subjected to huge tensile force applied by the fishing vessel. Therefore, the cover plate, which is fixedly connected to the tow rope connecting block, also needs to bear this tensile force. Due to the influence of unstable sea conditions during the navigation of the fishing vessel, the cover plate will be subjected to reciprocating impacts in the direction perpendicular to the sealing surface, which will seriously affect the stability of the seal.

[0007] 2. The towing cable connecting block also needs to be able to move horizontally to adjust the posture of the mesh plate in the water, so the cover plate also needs to move relative to the mounting bracket. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a sealing structure for a trawl net plate water layer adjustment mechanism, which can slide parallel to the sealing surface while the cover plate is subjected to reciprocating impact force perpendicular to the sealing surface, and maintain the sealing effect, thereby reducing the impact caused by the friction force generated by the sealing ring.

[0009] The technical solution adopted by the present invention to solve its technical problem is: to provide a sealing structure for a water layer adjustment mechanism for a trawl net, including a water layer adjustment mechanism and a traction cable connecting block, characterized in that the top surface of the water layer adjustment mechanism is provided with a cover plate, and a first waterproof sealing chamber is formed between the cover plate and the water layer adjustment mechanism by a sealing ring provided in a sealing groove on the top surface of the water layer adjustment mechanism; the top surface of the water layer adjustment mechanism is also provided with a low-friction pad, the top surface of the low-friction pad being slightly higher than the top surface of the water layer adjustment mechanism; the cover plate is provided with sliding grooves on both sides, and the top surface of the water layer adjustment mechanism is provided with sliding rails that match the sliding grooves on both sides; the cover plate can slide parallel to the top surface of the water layer adjustment mechanism through the sliding grooves and sliding rails.

[0010] Furthermore, the variable water layer adjustment mechanism includes a bidirectional rotatable drive motor, a reducer, a screw, a slider, and a guide rail. The guide rail is arranged parallel to the slide rail. The output shaft of the drive motor is connected to the input end of the reducer. The output end of the reducer is connected to the screw. The screw and the guide rail are parallel to each other. The slider is mounted on the screw to form a ball screw transmission structure. The slider is slidably mounted on the guide rail. The traction cable connecting block is fixedly connected to the slider. The slider and the cover plate are fixedly connected by bolts.

[0011] Furthermore, the drive motor and reducer are disposed in the second waterproof sealed chamber, and the second waterproof sealed chamber and the first waterproof sealed chamber are connected by an O-ring disposed outside the screw to form a rotational seal.

[0012] Furthermore, the first waterproof sealed chamber is filled with lubricating oil.

[0013] Furthermore, the side of the first waterproof sealed chamber is provided with an oil drain hole for emptying the lubricating oil, and the oil drain hole is sealed by a sealing bolt.

[0014] Furthermore, the sealing ring has a circular cross-section.

[0015] Furthermore, the low-friction pad is a graphite pad, and the low-friction pad is fixed to the top surface of the water layer adjustment mechanism by bolts, with the top surface of the bolts being lower than the top surface of the low-friction pad.

[0016] Furthermore, all exposed threaded connections in the variable water layer adjustment mechanism are waterproofed.

[0017] Beneficial effects

[0018] This invention provides waterproof sealing protection for the transmission mechanism and drive motor of the water level adjustment mechanism by means of a double waterproof sealing chamber. The inlet and outlet of the second waterproof sealing chamber are located inside the first waterproof sealing chamber, further reducing the risk of water ingress into the drive motor.

[0019] To address the issue of the first waterproof sealing chamber cover being subjected to reciprocating impacts underwater, the guide rails located within the water level adjustment mechanism and the slide rails on both sides of the water level adjustment mechanism together form an I-shaped stabilizing structure, which can play a role in resisting tension. While reducing the impact on the horizontal moving screw, it also prevents the problem of excessive gap between the cover and the water level adjustment mechanism leading to sealing failure.

[0020] The top surface of the water level adjustment mechanism is equipped with a low-friction pad, which mainly serves to resist pressure. When the traction connecting block drives the cover plate to move horizontally, it can prevent the cover plate from being pressed against the housing of the water level adjustment mechanism due to the huge water pressure and being unable to move.

[0021] In addition, by filling the first waterproof sealed chamber with lubricating oil, firstly, the smoothness of the ball screw drive can be ensured; secondly, the friction of the top sealing ring can be reduced, making it easier for the cover to slide; and thirdly, the pressure inside the first waterproof sealed chamber can be maintained, reducing the risk of the shell being deformed by water pressure. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the installation of a trawl net plate water layer adjustment mechanism.

[0023] Figure 2 for Figure 1 A three-dimensional view of the water layer regulation mechanism.

[0024] Figure 3 for Figure 1 Cross-sectional view of the water layer regulation mechanism.

[0025] Figure 4 for Figure 2 A three-dimensional view of the intermediate water layer regulating mechanism without a cover.

[0026] Among them, 1-mesh plate; 2-water layer adjustment mechanism; 3-traction cable connecting block; 4-cover plate; 5-sealing ring; 6-first waterproof sealing chamber; 7-low friction pad; 8-top surface; 9-slide groove; 10-slide rail; 11-drive motor; 12-screw; 13-slider; 14-guide rail; 15-second waterproof sealing chamber; 16-O-ring; 17-sealing bolt.

[0027] The same markings in each diagram represent the same component. Detailed Implementation

[0028] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0029] like Figure 1 As shown, a water layer adjustment mechanism 2 for a trawl net is installed at the center of the net 1 in the height direction via a rotating joint, and is connected to the towing line of the fishing vessel via a towing line connecting block 3. Figure 3 As shown, the variable water layer adjustment mechanism 2 includes a bidirectional rotatable drive motor 11, a reducer, a screw 12, a slider 13, and a guide rail 14. The output shaft of the drive motor 11 is connected to the input end of the reducer, and the output end of the reducer is connected to the screw 12. The screw 12 and the guide rail 14 are parallel to each other. The slider 13 is mounted on the screw 12 to form a ball screw transmission structure. The slider 13 is slidably mounted on the guide rail 14. The traction cable connecting block 3 is fixedly connected to the slider 13 by a thread.

[0030] like Figure 2 , 3 As shown in Figure 4, the present invention provides a sealing structure for a water layer adjustment mechanism 2 of a trawl net, used to keep the water layer adjustment mechanism 2 completely sealed. A cover plate 4 is provided on the top surface 8 of the water layer adjustment mechanism 2. A first waterproof sealing chamber 6 is formed between the cover plate 4 and the water layer adjustment mechanism 2 by a sealing ring 5 disposed in the sealing groove of the top surface 8 of the water layer adjustment mechanism 2. The first waterproof sealing chamber 6 prevents the components used to adjust the position of the traction cable connecting block 3, such as the screw 12, slider 13, and guide rail 14, from being corroded by seawater immersion.

[0031] Furthermore, the drive motor 11 and the reducer are housed within the second waterproof sealed chamber 15, and a rotational seal is formed between the second waterproof sealed chamber 15 and the first waterproof sealed chamber 6 via an O-ring 16 located outside the screw 12. The second waterproof sealed chamber 15 further protects the electrical equipment from seawater immersion corrosion.

[0032] To ensure the sealing solution remains effective when the water level adjustment mechanism 2 adjusts the position of the traction connecting block 3, a low-friction pad 7 is provided on the top surface 8 of the water level adjustment mechanism 2. The top surface of the low-friction pad 7 is slightly higher than the top surface 8 of the water level adjustment mechanism 2, primarily serving to resist pressure. This prevents the cover plate 4 from being crushed against the housing of the water level adjustment mechanism 2 due to excessive water pressure when the traction connecting block 3 moves the cover plate 4 horizontally. The cover plate 4 has sliding grooves 9 on both sides, and the top surface 8 of the water level adjustment mechanism 2 has sliding rails 10 on both sides that match the sliding grooves 9. The guide rails 14, screw 12, cover plate 4, top surface 8, sliding grooves 9, and sliding rails 10 are parallel to each other, allowing the cover plate 4 to slide parallel to the top surface 8 of the water level adjustment mechanism 2 via the sliding grooves 9 and sliding rails 10. The slider 13 is fixedly connected to the cover plate 4 by bolts.

[0033] The traction cable connecting block 3, slider 13 and cover plate 4 form a whole. The whole is connected to the slide rail 10 through the upper cover plate 4 and to the guide rail 14 through the lower slider 13, forming an I-shaped stable structure. This structure can resist tension and reduce the impact on the horizontal moving screw 12 while preventing the problem of sealing failure caused by excessive gap between the cover plate 4 and the water layer adjustment mechanism 2.

[0034] Furthermore, the sealing ring 5 has a circular cross-section, which helps to reduce friction during sliding while ensuring a seal.

[0035] Furthermore, the low-friction pad 7 is preferably a graphite pad, but other blocky materials that are not easily corroded by seawater, have high strength, and low surface friction can also be selected as pads. The low-friction pad 7 is fixed to the top surface 8 of the water layer adjustment mechanism 2 by bolts. The top surface of the bolts must be lower than the top surface of the low-friction pad 7 to avoid affecting the sliding of the cover plate 4.

[0036] Furthermore, the first waterproof sealed chamber 6 is filled with lubricating oil, and the side of the first waterproof sealed chamber 6 is provided with an oil drain hole for emptying the lubricating oil, which is sealed by a sealing bolt 17. By filling the first waterproof sealed chamber 6 with lubricating oil, firstly, the smoothness of the ball screw drive can be ensured; secondly, the friction of the sealing ring 5 inside the top surface 8 can be reduced, making it easier for the cover plate 4 to slide; and thirdly, the pressure inside the first waterproof sealed chamber 6 can be maintained, reducing the risk of deformation of the shell due to water pressure.

[0037] Furthermore, all exposed threaded connections in the variable water level adjustment mechanism 2 are waterproofed, such as the four bolts on the cover plate 4 used for fixing to the slider 13 and the two sealing bolts 17 located at the oil drain hole on the side of the variable water level adjustment mechanism 2. The waterproofing can be achieved using sealing rings 5, thread sealant, or other thread sealing solutions.

Claims

1. A sealing structure for a water layer adjustment mechanism of a trawl net, comprising a water layer adjustment mechanism (2) and a traction cable connecting block (3), characterized in that, The top surface (8) of the water layer regulating mechanism (2) is provided with a cover plate (4). The cover plate (4) and the water layer regulating mechanism (2) are connected by a sealing ring (5) located in the sealing groove on the top surface of the water layer regulating mechanism (2) to form a first waterproof sealing chamber (6). The top surface (8) of the water layer regulating mechanism (2) is also provided with a low friction pad (7). The top surface of the low friction pad (7) is slightly higher than the top surface (8) of the water layer regulating mechanism (2). The cover plate (4) is provided with sliding grooves (9) on both sides. The top surface (8) of the water layer regulating mechanism (2) is provided with slide rails (10) that match the sliding grooves (9) on both sides. The cover plate (4) can slide parallel to the top surface (8) of the water layer regulating mechanism (2) through the sliding grooves (9) and slide rails (10). The water layer adjustment mechanism (2) includes a bidirectional rotatable drive motor (11), a reducer, a screw (12), a slider (13), and a guide rail (14). The guide rail (14) is arranged parallel to the slide rail (10). The output shaft of the drive motor (11) is connected to the input end of the reducer. The output end of the reducer is connected to the screw (12). The screw (12) and the guide rail (14) are parallel to each other. The slider (13) is mounted on the screw (12) to form a ball screw transmission structure. The slider (13) is slidably mounted on the guide rail. The traction cable connecting block (3) is fixedly connected to the slider (13). The slider (13) is fixedly connected to the cover plate (4) by bolts.

2. The sealing structure for a water layer adjustment mechanism for a trawl net as described in claim 1, characterized in that, The drive motor (11) and reducer are located inside the second waterproof sealing chamber (15). The second waterproof sealing chamber (15) and the first waterproof sealing chamber (6) are connected by an O-ring (16) located outside the screw (12) to form a rotational seal.

3. The sealing structure for a water layer adjustment mechanism for a trawl net as described in claim 1, characterized in that, The first waterproof sealed chamber (6) is filled with lubricating oil.

4. The sealing structure for a water layer adjustment mechanism of a trawl net as described in claim 3, characterized in that, The side of the first waterproof sealed chamber (6) is provided with an oil drain hole for emptying the lubricating oil, and the oil drain hole is sealed by a sealing bolt (17).

5. A sealing structure for a trawl net plate water layer adjustment mechanism according to claim 1, characterized in that, The sealing ring (5) has a circular cross-section.

6. A sealing structure for a trawl net plate water layer adjustment mechanism according to claim 1, characterized in that, The low-friction pad (7) is a graphite pad. The low-friction pad (7) is fixed to the top surface of the water layer adjustment mechanism (2) by bolts. The top surface of the bolts is lower than the top surface of the low-friction pad (7).

7. A sealing structure for a water layer adjustment mechanism for a trawl net as described in claim 1, characterized in that, All exposed threaded connections in the water layer adjustment mechanism (2) are waterproofed.

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