Anti-loose and anti-rust nut for trailer hook

Abstract

The utility model provides a kind of anti-loose anti-rust nut for trailer hook, including nut main body, the bottom of nut main body is fixedly installed with mounting seat, the bottom of mounting seat is equipped with thread groove, the bottom of mounting seat is provided with connecting seat, the top of connecting seat is fixedly installed with thread ring, the outside of connecting seat is provided with fixed band ring, the outside of nut main body is provided with anti-loose anti-rust assembly.The anti-loose anti-rust nut for trailer hook, by setting anti-loose anti-rust assembly, constructs the three anti-loose systems of elastic pre-tightening, mechanical limiting and double adhesion, avoids anti-loose piece to shift in vibration, forms basic pre-tightening force, while the reinforcing anti-skid stripe in fixed band ring inside is closely adhered with mounting seat and connecting seat, combines the friction enhancement effect of anti-rust anti-skid sleeve belt, further weakens the axial loosening tendency of nut, greatly reduces the risk of trailer hook falling off, can isolate rainwater, dust and other external corrosive media, and mounting hole is sealed and protected by fixed sealing column.

Description

Technical Field

[0001] This utility model relates to the field of fastener technology, and in particular to an anti-loosening and anti-rust nut for trailer hooks. Background Technology

[0002] In vehicle emergency rescue systems, tow hooks are the key link between disabled vehicles and rescue vehicles. The reliability of their connection directly affects the success or failure of rescue operations and the safety of personnel. As the core fastener connecting the tow hook to the vehicle chassis, the nut must not only withstand the continuous vibration caused by road bumps, rapid acceleration and braking during vehicle operation, but also resist the multiple corrosions of complex outdoor environments, including salt spray corrosion in coastal areas, chemical damage from de-icing agents in northern winters, and the penetration of rainwater and mud during daily use. Slight negligence may lead to connection failure and cause serious safety accidents. Therefore, there is a special need for a non-loosening and rust-proof nut for tow hooks.

[0003] Chinese patent CN222959537U, published on June 10, 2025, discloses an anti-loosening rear trailer hook nut tube. It improves the deformation elasticity of the shock-absorbing pad through a spherical cavity, enhances the squeezing and frictional force of the anti-slip groove, and absorbs and dissipates externally transmitted vibrations to a certain extent, thus improving the shock resistance of the rear trailer hook nut tube connection structure. However, this anti-loosening rear trailer hook nut tube relies heavily on a single mechanism in use, employing the elastic preload of an elastic washer or a single-sided mechanical locking element for limiting the position. It does not form a multi-dimensional, collaborative anti-loosening system. In high-frequency vibration environments of vehicles, the elastic components of preloaded structures are prone to fatigue decay, gradually losing preload and causing an increase in the gap between the nut and the screw, leading to loosening. Simply applying a plating layer to the nut surface or a small amount of sealant to the threads does not achieve full-dimensional sealing protection. These structures are often integrated designs with high component integration, requiring specialized tools for positioning during assembly, making the process cumbersome and inefficient. Furthermore, the lack of sealing at the connection points allows corrosive media to easily penetrate through the threaded gaps, causing the threads to seize. This not only affects subsequent disassembly and maintenance but also weakens the connection strength and shortens the nut's lifespan. Utility Model Content

[0004] The purpose of this utility model is to provide an anti-loosening and anti-rust nut for trailer hooks, to solve the problems mentioned in the background art. Existing anti-loosening trailer hook nuts often rely on a single mechanism, using the elastic preload of an elastic washer or a single-sided mechanical locking element for limiting position, failing to form a multi-dimensional collaborative anti-loosening system. In high-frequency vibration environments of vehicles, the elastic element of a single elastic preload structure is prone to fatigue decay, gradually losing preload and increasing the gap between the nut and the screw, thus causing loosening. Simply applying a plating layer to the nut surface or a small amount of sealant to the threads does not achieve full-dimensional sealing protection. Most are integrated designs with high component integration, requiring specialized tools for positioning during assembly, making the operation cumbersome and inefficient. The lack of sealing at the connection points allows corrosive media to easily penetrate through the threaded gaps, causing the threads to seize, affecting subsequent disassembly and maintenance, weakening the connection strength, and shortening the nut's service life.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a rust-proof and anti-loosening nut for a trailer hook, comprising a nut body, an anti-rust and anti-slip sleeve provided on the outer side of the nut body, a mounting base fixedly installed at the bottom of the nut body, a threaded groove formed at the bottom of the mounting base, a connecting seat provided at the bottom of the mounting base, a threaded ring fixedly installed at the top of the connecting seat, a fixing ring provided on the outer side of the connecting seat, and reinforcing anti-slip stripes provided on the inner side of the fixing ring; and an anti-loosening and anti-rust component provided on the outer side of the nut body. The rust-prevention component includes an annular mounting groove at the top of the nut body, a snap-fit ​​groove at the bottom of the nut body, an elastic anti-loosening ring inside the nut body, a snap-fit ​​post fixedly installed at the bottom of the elastic anti-loosening ring, a mounting hole on the outer side of the nut body, a fixed sealing post fixedly installed on the outer side of the nut body, a placement groove on the outer side of the fixed sealing post, a tightening spring fixedly installed inside the fixed sealing post, and an anti-loosening steel ball fixedly installed at the end of the tightening spring away from the fixed sealing post.

[0006] Preferably, the nut body is tightly fitted with the anti-rust and anti-slip sleeve, and the threaded groove and the threaded ring are threadedly connected.

[0007] Preferably, the size of the mounting base is consistent with the size of the connecting base, and the height of the mounting base and connecting base assembly is consistent with the height of the fixing ring.

[0008] Preferably, the reinforced anti-slip stripes are provided in multiple identical sets, and the multiple sets of reinforced anti-slip stripes are located on the inner side of the fixing belt ring in a ring distribution, and the mounting base and connecting base are tightly fitted with the reinforced anti-slip stripes.

[0009] Preferably, the nut body, anti-rust and anti-slip sleeve, and anti-loosening and anti-rust components are provided in two identical sets, and the two sets of the nut body, anti-rust and anti-slip sleeve, and anti-loosening and anti-rust components are symmetrically distributed about the horizontal center line of the fixing ring, and the connecting seat is fixedly connected to the nut body.

[0010] Preferably, the elastic anti-loosening ring and the annular mounting groove are interference fit, and multiple sets of the snap-fit ​​groove and snap-fit ​​post are provided, and the multiple sets of the snap-fit ​​groove and snap-fit ​​post are one-to-one corresponding and compatible.

[0011] Preferably, the mounting holes, fixing sealing posts, placement grooves, tightening springs, and anti-loosening steel balls are all provided in multiple identical sets, and the multiple sets of mounting holes, fixing sealing posts, placement grooves, tightening springs, and anti-loosening steel balls are located on the outer side of the nut body in a ring-shaped equidistant distribution, and the anti-loosening steel balls are slidably connected to the inner wall of the nut body.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: This trailer hook anti-loosening and anti-rust nut, by setting anti-loosening and anti-rust components, constructs a triple anti-loosening system of elastic pre-tightening, mechanical limiting, and double fitting. The elastic anti-loosening ring is embedded into the annular mounting groove through interference fit, and with the precise positioning of the locking post and the locking groove, it prevents the anti-loosening component from shifting during vibration, forming a basic pre-tightening force. At the same time, the reinforced anti-slip stripes on the inner side of the fixing band ring are tightly fitted with the mounting base and connecting base, and combined with the friction enhancement effect of the anti-rust and anti-slip sleeve, it further weakens the axial loosening tendency of the nut, even when... Even under extreme conditions of high-frequency vehicle vibration, it can remain stable and secure, significantly reducing the risk of trailer hitch detachment. The outer anti-rust and anti-slip sleeve covers the outside of the nut body, isolating it from external corrosive media such as rainwater and dust. The fixed sealing post forms a sealed protection for the mounting hole, avoiding the defects of traditional open mounting holes that are prone to impurities entering, ensuring the long-term performance of the tightening spring and anti-loosening steel ball. The threaded connection between the threaded groove and the threaded ring, combined with the wrap-around protection of the fixed ring, seals the connection gap between the mounting seat and the connecting seat, preventing corrosive media from entering the threaded mating surface, and significantly extending the service life of the nut. Attached Figure Description

[0013] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a schematic diagram of the structure of the fixed belt ring and the reinforced anti-slip stripes of this utility model. Figure 3 This is a top view structural diagram of the present invention; Figure 4 This is a schematic diagram of the interlocking structure of the annular mounting groove and the snap-fit ​​groove of this utility model; Figure 5 This is a schematic diagram of the structure in which the mounting hole and the anti-loosening steel ball of this utility model cooperate.

[0014] In the diagram: 1. Nut body; 2. Rust-proof and anti-slip sleeve; 3. Mounting base; 4. Threaded groove; 5. Connecting base; 6. Threaded ring; 7. Fixing ring; 8. Reinforced anti-slip stripes; 9. Anti-loosening and anti-rust component; 901. Annular mounting groove; 902. Snap-fit ​​groove; 903. Elastic anti-loosening ring; 904. Snap-fit ​​post; 905. Mounting hole; 906. Fixing sealing post; 907. Placement groove; 908. Tightening spring; 909. Anti-loosening steel ball. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] Please see Figure 1-5 This utility model provides a technical solution: an anti-loosening and anti-rust nut for a trailer hook, comprising a nut body 1, an anti-rust and anti-slip sleeve 2 on the outer side of the nut body 1, a mounting base 3 fixedly installed at the bottom of the nut body 1, a threaded groove 4 at the bottom of the mounting base 3, a connecting base 5 at the bottom of the mounting base 3, a threaded ring 6 fixedly installed at the top of the connecting base 5, a fixing ring 7 on the outer side of the connecting base 5, and reinforcing anti-slip stripes 8 on the inner side of the fixing ring 7, and an anti-loosening and anti-rust component 9 on the outer side of the nut body 1; the anti-loosening and anti-rust component 9 includes an annular mounting groove 901, which is located at the top of the nut body 1, a snap-fit ​​groove 902 at the bottom inside the nut body 1, an elastic anti-loosening ring 903 inside the nut body 1, a snap-fit ​​post 904 fixedly installed at the bottom of the elastic anti-loosening ring 903, and a mounting hole 905 on the outer side of the nut body 1. A fixed sealing post 906 is fixedly installed on the outside of the fixed sealing post 906. A placement groove 907 is opened on the outside of the fixed sealing post 906. A tightening spring 908 is fixedly installed inside the fixed sealing post 906. An anti-loosening steel ball 909 is fixedly installed at the end of the tightening spring 908 away from the fixed sealing post 906. By setting the anti-loosening and anti-rust components 9, a triple anti-loosening system of elastic pre-tightening, mechanical limiting and double fitting is constructed. The elastic anti-loosening ring 903 is embedded into the annular mounting groove 901 through interference fit. With the precise positioning of the locking post 904 and the locking groove 902, the anti-loosening component is prevented from shifting during vibration and a basic pre-tightening force is formed. At the same time, the reinforced anti-slip stripe 8 on the inner side of the fixed band ring 7 is tightly fitted with the mounting seat 3 and the connecting seat 5. Combined with the friction enhancement effect of the anti-rust and anti-slip sleeve 2, the axial loosening tendency of the nut is further weakened. Even under the extreme working conditions of high-frequency vibration of the vehicle, it can still maintain stable fastening and greatly reduce the risk of the trailer hook falling off.

[0017] Furthermore, the nut body 1 and the anti-rust and anti-slip sleeve 2 fit tightly together, and the threaded groove 4 and the threaded ring 6 are threadedly connected. By setting the threaded groove 4 and the threaded ring 6, not only is there reliable connection strength, which can withstand the axial tensile force and radial shear force generated during trailer operation, but it also provides convenience for the assembly and maintenance of the components. When it is necessary to replace the nut body 1 or the connecting seat 5, it is only necessary to rotate and separate the threaded groove 4 and the threaded ring 6 to complete the disassembly without damaging the overall structure. At the same time, the sealing of the threaded connection can initially block the intrusion of some corrosive media. Combined with the full coverage protection of the outside of the nut body 1 by the anti-rust and anti-slip sleeve 2, a dual basic guarantee of connection sealing and surface protection is formed.

[0018] Furthermore, the size of the mounting base 3 is consistent with that of the connecting base 5, and the height of the assembly of the mounting base 3 and the connecting base 5 is consistent with the height of the fixing ring 7. By setting the mounting base 3 and the connecting base 5, the precise matching of the dimensions allows the fixing ring 7 to completely wrap around the assembly of the mounting base 3 and the connecting base 5. This not only avoids the fixing ring 7 from becoming loose or experiencing uneven force due to size deviation, but also enhances the structural stability of the intermediate connection part through the constraint effect of the fixing ring 7. The force on the nut body 1 is evenly transferred to the fixing ring 7 through the mounting base 3 and the connecting base 5, dispersing the stress concentration at a single connection point. At the same time, it provides a flat and suitable installation base for the subsequent application of the anti-slip stripe 8.

[0019] Furthermore, multiple sets of reinforced anti-slip stripes 8 are provided, and these multiple sets of reinforced anti-slip stripes 8 are located on the inner side of the fixing ring 7 in a ring distribution. The mounting base 3 and the connecting base 5 are both tightly fitted with the reinforced anti-slip stripes 8. By setting multiple sets of reinforced anti-slip stripes 8, the ring distribution design ensures that the friction force is evenly distributed along the circumference, avoiding relative slippage caused by insufficient local friction. When the nut is subjected to vibration and tends to loosen, the reinforced anti-slip stripes 8 can form a reverse constraint through frictional resistance, weakening the axial loosening force. At the same time, the tightly fitted structure can also fill the small gaps on the outside of the assembly of mounting base 3 and connecting base 5, further blocking the intrusion of corrosive media such as dust and rainwater, and realizing the dual functions of anti-slip resistance and auxiliary sealing.

[0020] Furthermore, the nut body 1, the anti-rust and anti-slip sleeve 2, and the anti-loosening and anti-rust component 9 are all provided with two identical sets, and the two sets of nut body 1, anti-rust and anti-slip sleeve 2, and anti-loosening and anti-rust component 9 are symmetrically distributed about the horizontal center line of the fixing ring 7. The connecting seat 5 is fixedly connected to the nut body 1. By setting two sets of nut body 1, anti-rust and anti-slip sleeve 2, and anti-loosening and anti-rust component 9, the symmetrical distribution makes the preload and locking force on the trailer hook screw evenly distributed along the axial direction, avoiding the force imbalance caused by unilateral tightening, significantly improving the stability and balance of the overall connection, while maintaining the basic tightening and protection functions, and greatly reducing the risk of single-point failure.

[0021] Furthermore, the elastic anti-loosening ring 903 and the annular mounting groove 901 are interference-fitted. Multiple sets of the snap-fit ​​groove 902 and snap-fit ​​post 904 are provided, and each set corresponds to and is compatible with the other. By setting multiple sets of snap-fit ​​grooves 902 and snap-fit ​​posts 904 and the elastic anti-loosening ring 903 and the annular mounting groove 901, precise positioning and reliable fixing of the elastic anti-loosening ring 903 are achieved. The interference fit ensures that the elastic anti-loosening ring 903 remains in a pre-compressed state within the annular mounting groove 901, continuously providing a stable elastic pre-tightening force. The multiple sets of snap-fit ​​grooves 902 and snap-fit ​​posts 904 limit the elastic anti-loosening ring 903 from the circumferential direction, preventing circumferential rotation or axial displacement during vibration, ensuring that the elastic pre-tightening force is evenly applied to the threaded mating surface. This lays a stable foundation for the triple anti-loosening system, ensuring pre-tightening and improving the long-term effectiveness and reliability of the anti-loosening structure.

[0022] Furthermore, the mounting holes 905, fixing sealing posts 906, placement grooves 907, tightening springs 908, and anti-loosening steel balls 909 are all provided in multiple identical sets. These multiple sets of mounting holes 905, fixing sealing posts 906, placement grooves 907, tightening springs 908, and anti-loosening steel balls 909 are located on the outer side of the nut body 1 in a ring-shaped, equidistant distribution. The anti-loosening steel balls 909 are slidably connected to the inner wall of the nut body 1. By providing multiple sets of mounting holes 905, fixing sealing posts 906, placement grooves 907, tightening springs 908, and anti-loosening steel balls 909, an all-around mechanical locking system is constructed. The system, with its annular and equidistant distribution, allows the anti-loosening steel balls 909 to retract into the mounting holes 905, forming a uniform mechanical limit. The elastic force of the tightening spring 908 can drive the anti-loosening steel balls 909 to adaptively conform to the contour of the mounting holes 905, achieving reliable locking. The fixed sealing post 906 forms a sealing protection for the tightening spring 908 and the anti-loosening steel balls 909, preventing impurities from entering and causing jamming. The placement groove 907 also provides sufficient space for spring compression, ensuring smooth expansion and contraction of the steel balls. The sliding connection ensures that the steel balls can slide smoothly along the thread surface during the tightening of the nut, without affecting assembly efficiency.

[0023] Working principle: First, the operator takes the elastic anti-loosening ring 903 and aligns its multiple sets of locking pins 904 at the bottom with the corresponding locking grooves 902 at the bottom of the nut body 1. Axial pressure is applied to make the elastic anti-loosening ring 903 embed into the annular mounting groove 901. Since the two are interference fit, it is necessary to ensure that the locking pins 904 are fully engaged in the locking grooves 902, and that the elastic anti-loosening ring 903 is tightly fitted with the inner wall of the annular mounting groove 901 without loosening or displacement. Then, the tightening spring 908 and the anti-loosening steel ball 909 are sequentially inserted into the mounting hole 905 on the outside of the nut body 1, ensuring that one end of the tightening spring 908 is in contact with the bottom of the mounting hole 905 and the other end is in close contact with the anti-loosening steel ball 909. The fixing sealing pin 906 is aligned with the open end of the mounting hole 905 and fixed, so that the anti-loosening steel ball 909... Nine spherical protrusions extend from the inner wall of the nut body 1 and can slide smoothly along the inner wall. The placement groove 907 faces outward to reserve space for spring compression. The anti-rust and anti-slip sleeve 2 is axially inserted along the outer side of the nut body 1 until the sleeve is completely and tightly fitted to the outer surface of the nut body 1 without wrinkles or gaps, completing the pre-assembly of a single set of nut bodies 1. Take two sets of pre-assembled nut bodies 1, align the bottom thread groove 4 of the mounting base 3 of one set with the threaded ring 6 on the top of the connecting base 5, and rotate the mounting base 3 clockwise until the thread groove 4 and the threaded ring 6 are completely screwed and tightened, realizing the fixed connection between the mounting base 3 and the connecting base 5. Insert the fixing ring 7 along the outer side of the connecting base 5 and adjust its position so that the multiple sets of reinforced anti-slip stripes 8 on the inner side of the fixing ring 7 face the outer surfaces of the mounting base 3 and the connecting base 5. Since the height of the assembly of mounting base 3 and connecting base 5 is consistent with the height of the fixing ring 7, after fitting it in, it is necessary to ensure that both ends of the fixing ring 7 are flush with the end faces of the two sets of nut bodies 1, and that the reinforcing anti-slip stripe 8 is tightly fitted with mounting base 3 and connecting base 5. Connect the other pre-assembled nut body 1 to the assembled connecting base 5 through its connecting base 5, repeating the screwing steps of thread groove 4 and thread ring 6, ultimately forming a double fastening structure symmetrically distributed around the fixing ring 7. Clean the surface of the trailer hook screw, removing oil, rust, and impurities, ensuring the thread surface is smooth and flat. Check whether the anti-rust and anti-slip sleeve 2 and the fixing sealing post 906 of this utility model nut are intact, whether the anti-loosening steel ball 909 slides smoothly, and whether the elastic anti-loosening ring 903 is free from aging and deformation. Hold the screw... The rust-proof and anti-slip sleeve 2 on the outer side of the main body 1 is used to align the internal thread of the nut body 1 with the end of the trailer hook screw. The nut is rotated clockwise. At this time, the anti-loosening steel ball 909 compresses the tightening spring 908 under the pressure of the screw thread slope, retracting into the mounting hole 905 and sliding smoothly along the thread surface. Tightening continues until the elastic anti-loosening ring 903 contacts the surface of the connected part. Torque is continued to be applied to cause the elastic anti-loosening ring 903 to undergo pre-compression deformation until the preset pre-tightening force is reached. At this time, the anti-loosening steel ball 909 forms a mechanical limit under the elastic force of the tightening spring 908. The reinforced anti-slip stripe 8 on the inner side of the fixing ring 7 fits tightly with the mounting base 3 and connecting base 5, completing the tightening. The fit between the anti-loosening steel ball 909 and the screw thread groove 4 is observed to ensure that multiple sets of steel balls are effectively limited.Check that the anti-rust and anti-slip sleeve 2 and the fixing ring 7 are intact, without displacement or damage. Regularly observe the anti-rust and anti-slip sleeve 2 for wear and cracks; replace it promptly if damage is found. Check that the fixing sealing post 906 is properly sealed; if loose or gaps are found, retighten or replace it. If the elastic anti-loosening ring 903 shows signs of aging or reduced preload, first remove the nut from the trailer hook bolt. Use a tool to pry the elastic anti-loosening ring 903 along the edge of the annular mounting groove 901 to disengage the locking post 904 from the locking groove 902. After removing the old part, install the new part according to the pre-installation steps, avoiding damage to the nut or bolt threads.

[0024] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A rust-proof and anti-loosening nut for a trailer hook, comprising a nut body (1), characterized in that: The outer side of the nut body (1) is provided with an anti-rust and anti-slip sleeve (2), the bottom of the nut body (1) is fixedly installed with a mounting base (3), the bottom of the mounting base (3) is provided with a threaded groove (4), the bottom of the mounting base (3) is provided with a connecting base (5), the top of the connecting base (5) is fixedly installed with a threaded ring (6), the outer side of the connecting base (5) is provided with a fixing belt ring (7), the inner side of the fixing belt ring (7) is provided with a reinforcing anti-slip stripe (8), and the outer side of the nut body (1) is provided with an anti-loosening and anti-rust component (9). The anti-loosening and anti-rust component (9) includes an annular mounting groove (901), which is located at the top of the nut body (1). A snap-fit ​​groove (902) is provided at the bottom of the nut body (1). An elastic anti-loosening ring (903) is provided inside the nut body (1). A snap-fit ​​post (904) is fixedly installed at the bottom of the elastic anti-loosening ring (903). An installation hole (905) is provided on the outside of the nut body (1). A fixed sealing post (906) is fixedly installed on the outside of the nut body (1). A placement groove (907) is provided on the outside of the fixed sealing post (906). A tightening spring (908) is fixedly installed inside the fixed sealing post (906). An anti-loosening steel ball (909) is fixedly installed at the end of the tightening spring (908) away from the fixed sealing post (906).

2. The anti-loosening and anti-rust nut for a trailer hook according to claim 1, characterized in that: The nut body (1) is tightly fitted with the anti-rust and anti-slip sleeve (2), and the threaded groove (4) and the threaded ring (6) are threadedly connected.

3. The anti-loosening and anti-rust nut for a trailer hook according to claim 1, characterized in that: The size of the mounting base (3) is consistent with the size of the connecting base (5), and the height of the assembly of the mounting base (3) and the connecting base (5) is consistent with the height of the fixing ring (7).

4. The anti-loosening and anti-rust nut for a trailer hook according to claim 1, characterized in that: The reinforced anti-slip stripes (8) are provided in multiple identical sets, and the multiple sets of reinforced anti-slip stripes (8) are located on the inner side of the fixing belt ring (7) in a ring distribution. The mounting seat (3) and the connecting seat (5) are both tightly fitted with the reinforced anti-slip stripes (8).

5. The anti-loosening and anti-rust nut for a trailer hook according to claim 1, characterized in that: The nut body (1), anti-rust and anti-slip sleeve (2) and anti-loosening and anti-rust component (9) are all provided with two identical sets, and the two sets of the nut body (1), anti-rust and anti-slip sleeve (2) and anti-loosening and anti-rust component (9) are symmetrically distributed about the horizontal center line of the fixing ring (7). The connecting seat (5) is fixedly connected to the nut body (1).

6. The anti-loosening and anti-rust nut for a trailer hook according to claim 1, characterized in that: The elastic anti-loosening ring (903) and the annular mounting groove (901) are interference fit. The snap-fit ​​groove (902) and the snap-fit ​​post (904) are provided with multiple sets of the same type, and the multiple sets of snap-fit ​​grooves (902) and snap-fit ​​posts (904) correspond one-to-one and are compatible.

7. The anti-loosening and anti-rust nut for a trailer hook according to claim 1, characterized in that: The mounting holes (905), fixed sealing posts (906), placement grooves (907), tightening springs (908), and anti-loosening steel balls (909) are all provided in multiple sets, and the multiple sets of mounting holes (905), fixed sealing posts (906), placement grooves (907), tightening springs (908), and anti-loosening steel balls (909) are located on the outside of the nut body (1) in a ring-shaped equidistant distribution, and the anti-loosening steel balls (909) are slidably connected to the inner wall of the nut body (1).

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