Fender end link structure

Abstract

This invention discloses a fender end link structure, which includes a chain and rotating parts connected to both ends of the chain. The rotating parts include a bracket and a rotating frame rotatably connected to the bracket, the rotating frame being able to rotate freely 360 degrees relative to the bracket. The chain includes a swivel and a stopped anchor chain connected to both ends of the swivel. The swivel includes a pull ring and a pin ring rotatably connected to one end of the pull ring, the pin ring being able to rotate freely 360 degrees relative to the pull ring. This invention improves the original single rubber fender end metal component into two independent, separate parts: a bracket and a rotating frame, with a pivot in between enabling 360-degree free rotation. A swivel is introduced in the middle of the chain to form a second rotating node. This structure effectively avoids entanglement between the fender and the mooring line, dilutes the torque generated on the mooring line by the fender's movement, and effectively prevents collisions between adjacent fenders when multiple fenders are used side-by-side, significantly improving the safety and lifespan of the fender.

Description

Technical Field

[0001] This invention relates to the field of ship mooring equipment technology, and in particular to a fender end link structure, which is especially suitable for fixing and connecting rubber fenders when ships are berthing or mooring between docks or between ships. Background Technology

[0002] Rubber fenders are a type of elastic buffer device widely used at the edges of docks or ships. They are primarily used to mitigate the impact forces between ships and docks, or between ships themselves, during berthing or mooring, reducing or eliminating damage to both the vessel and the dock. As a crucial component of a ship's mooring system, the reliability of the rubber fender's fixing method and connection structure directly affects the safety of ship operations and the service life of the equipment.

[0003] In existing rubber fender installations, the rubber fender is typically fixed to mooring lines (such as cables, steel cables, or anchor chains) via metal connectors at both ends. Specifically, the mooring lines pass through or are attached to the metal connectors at both ends of the rubber fender, securing it to the dock, ship's hull, or other fixed structure. Because the rubber fender must withstand the enormous impact forces generated when a ship berths, as well as the repeated pulling forces under complex sea conditions such as waves and tides, the tension exerted by the mooring lines on the metal connectors at the ends of the rubber fender is considerable. This necessitates that the metal connectors at the ends of the rubber fender possess sufficient structural strength and load-bearing capacity.

[0004] However, due to the limitations of the rubber fender's own structural dimensions and installation space, the external dimensions of the metal fittings at the ends of the rubber fender cannot be designed to be too large. Mooring lines can only be secured to the rubber fender through these metal fittings at both ends, which presents a contradictory requirement for the design of these fittings: they must be small enough to meet installation and usage requirements, while also being able to withstand sufficiently large tensile forces to ensure the safety and reliability of the connection. This contradiction largely restricts and limits the structural and functional improvements and innovations in the metal fittings at the ends of the rubber fender.

[0005] Currently available rubber fender end fittings suffer from significant technical deficiencies in their structural design. Firstly, most existing rubber fender end fittings employ a fixed structure, with connections to the fender body and between their individual components being either fixed or possessing only limited rotational freedom, with the vast majority unable to achieve 360-degree free rotation. When the rubber fender floats in seawater, the rise and fall of waves and tides, along with the ship's movement, causes complex attitude changes and swaying motions. Because the end fittings cannot rotate freely, the mooring ropes cannot achieve relatively free rotational coordination with the fender. This makes the undulating motion of the rubber fender in the sea prone to causing the mooring ropes to twist and become entangled, severely affecting the normal function and service life of the rubber fender, and also posing potential risks to the ship's mooring safety. The problem of rubber fenders easily becoming entangled with mooring ropes as they float in the sea with the rise and fall of waves and tides has not yet been effectively solved in existing technologies.

[0006] On the other hand, in practical engineering applications, it is often necessary to place two or more rubber fenders side by side to provide a larger buffer area and stronger impact energy absorption capacity. For example, in ship-to-ship barge operations, when two ships are berthed side by side for loading and unloading, to avoid the danger of direct collision between the two ships, sufficient rubber fenders and accessories to absorb their impact energy need to be installed between the two sides that are berthed side by side. However, the existing end metal structure of rubber fenders cannot effectively solve the problem of mutual interference when multiple fenders are placed side by side. Since the end metal parts cannot rotate freely, adjacent rubber fenders move independently under the action of waves, lacking a coordination mechanism with each other. This easily leads to collisions, squeezing, and friction between adjacent rubber fenders, which not only accelerates the wear and damage of the fender itself, but also generates additional torsional stress on the mooring ropes, further aggravating the risk of torsion and entanglement of the mooring ropes, and reducing the safety and reliability of the entire mooring system.

[0007] In the field of anchor chain connection technology, it is known to install swivels in the anchor end links of the anchor chain to prevent excessive twisting of the anchor chain during anchoring. The swivel's bolt should face the middle link to reduce friction and jamming. The bolt and its body should be on the same centerline and able to rotate freely. However, this swivel structure is mainly used for connections between internal links of the anchor chain to solve the twisting problem of the anchor chain itself, and has not been applied to the end connection structure of rubber fenders. Similarly, in the installation of inflatable rubber fenders, there is also a scheme that uses a 360° swivel joint to connect the chain and the fender flange, with the chain and the fender flange directly connected by a 360° swivel ring and shackle. However, this type of scheme only provides a single degree of rotational freedom between the fender flange and the chain. When multiple rubber fenders are used side by side, it still cannot effectively solve the problem of mutual collision and interference between adjacent fenders caused by wave action, nor can it fundamentally eliminate the torsional stress concentration on the mooring rope caused by the movement of the fender.

[0008] In summary, there is an urgent need in the existing technology for a fender end connection structure that can meet the tensile strength requirements of the rubber fender end connection, achieve 360-degree free rotation, and effectively solve the problems of collision and mooring rope entanglement when multiple rubber fenders are placed side by side. Summary of the Invention

[0009] To address the shortcomings of existing technologies, the present invention aims to provide a fender end linking structure. This linking structure, through ingenious mechanical design, achieves 360-degree free rotation of multiple nodes while ensuring sufficient tensile strength. It can effectively prevent entanglement between the rubber fender and the mooring line, and effectively dilute and release the torsional stress on the mooring line caused by the rubber fender's movement with the waves in the sea. At the same time, when multiple rubber fenders are placed side by side, it can effectively prevent adjacent rubber fenders from colliding with each other, significantly improving the safety and service life of the rubber fenders.

[0010] The above-mentioned objective of this invention is achieved through the following technical solutions: The present invention provides a fender end link structure, including a chain and rotating parts respectively connected to both ends of the chain; The rotating part includes a bracket and a rotating frame rotatably connected to the bracket. The rotating frame can rotate freely 360 degrees relative to the bracket, and the rotating frame is connected to one end of the chain. The chain includes a swivel and a stop anchor chain connected to both ends of the swivel, with the end of the stop anchor chain away from the swivel connected to the corresponding connection part of the rotating frame. The swivel includes a pull ring and a pin ring rotatably connected to one end of the pull ring. The pin ring is capable of 360-degree free rotation relative to the pull ring. The end of the pin ring away from the pull ring is connected to one of the studded anchor chains, and the end of the pull ring away from the pin ring is connected to the other studded anchor chain.

[0011] As a preferred embodiment of the present invention, the bracket includes a ring, a circular plate, and four connecting plates fixedly connected between the ring and the circular plate. The circular plate is located above the ring and is coaxially arranged with the ring. The outer diameter of the circular plate is smaller than the outer diameter of the ring. The bottom end of the connecting plate is fixedly connected to the ring by opening a groove-shaped contact surface, and the top end of the connecting plate is fixedly connected to the side wall and bottom edge of the circular plate by opening an L-shaped contact surface. The four connecting plates are evenly distributed on the ring, so that the bracket as a whole has a frustum-shaped structure.

[0012] As a preferred embodiment of the present invention, a through hole is provided on the circular plate, and a copper sleeve is fixedly installed in the through hole. The copper sleeve is used to reduce frictional resistance during rotation and improve the wear resistance of the rotational fit.

[0013] As a preferred embodiment of the present invention, the rotating frame includes a base plate, two ear plates integrally formed and fixedly connected to the base plate, and a rotating shaft fixedly connected to one end of the base plate away from the ear plates; A first bolt and a first nut threadedly connected to the two ear plates are connected through the two ear plates. One end of the stop anchor chain is sleeved on the first bolt. The detachable connection between the stop anchor chain and the rotating frame is achieved by the fastening action of the first bolt and the first nut. The outer wall of the end of the rotating shaft away from the base plate has a partial external thread section. After one end of the rotating shaft passes through the copper sleeve on the circular plate, a second nut and a third nut are sequentially threaded onto the thread section. The second nut and the third nut axially limit the rotating shaft to be rotatably fixed on the bracket.

[0014] As a preferred embodiment of the present invention, reinforcing plates are fixedly connected to both sides between the two ear plates, and the bottom of the reinforcing plates is fixedly connected to the base plate. The reinforcing plates are used to enhance the connection strength between the ear plates and the base plate. The ear plate adopts a slanted layout design with a narrower upper part and a wider lower part, that is, the upper width of the ear plate is smaller than the lower width, in order to improve the structural stability and bending resistance of the ear plate when subjected to tensile loads.

[0015] As a preferred technical solution of the present invention, a bolt pin and a bolt pin nut that cooperate with the bolt pin are installed through the side wall of the threaded end of the first bolt that protrudes from the first nut. The cooperation between the bolt pin and the bolt pin nut prevents the first nut from loosening and falling off during operation. A first nut locking bolt is installed on the side wall of the first nut to further lock the first nut in a tightened position.

[0016] As a preferred embodiment of the present invention, a second nut locking bolt is installed on the side wall of the second nut to lock the fastening position of the second nut. A third nut locking bolt is installed on the side wall of the third nut to lock the third nut in a fastened position.

[0017] As a preferred embodiment of the present invention, a shaft pin and a shaft pin nut that cooperate with the shaft are installed through the side wall of the threaded end of the shaft that passes through the third nut. The cooperation between the shaft pin and the shaft pin nut prevents the second nut and the third nut from loosening and axially moving during operation.

[0018] As a preferred embodiment of the present invention, a washer is provided between the second nut and the copper sleeve, and the washer is sleeved on the rotating shaft to distribute the axial load and protect the end face of the copper sleeve. The smooth surface of the rotating shaft and the inner hole of the copper sleeve are fitted with a clearance to achieve a rotational fit.

[0019] As a preferred technical solution of the present invention, the rotating shaft and the base plate adopt a composite connection method of threaded connection and welding fixation to improve the connection strength and overall tensile load bearing capacity between the rotating shaft and the rotating frame; The grooved and L-shaped contact surfaces between the four connecting plates and the ring and the circular plate are fixed by full welding to increase the welding contact area and improve the connection strength and structural rigidity of the welding area.

[0020] As a preferred embodiment of the present invention, the bottom of the bracket is fixedly connected to the end face of the rubber fender by fasteners, the rotating frame is rotatably connected to the bracket by the rotating shaft, and the stopped anchor chains at both ends of the chain are respectively connected to the rotating frame at the corresponding ends, forming a complete load transfer path from the end face of the rubber fender to the mooring point.

[0021] As a preferred technical solution of the present invention, when two or more rubber fenders are placed side by side, the adjacent rubber fenders are connected by the fender end linking structure at their respective ends, and the distance between the metal parts at the ends of the adjacent rubber fenders is controlled to be about 90 centimeters. The swivel in each fender end link structure is located in the middle of the connecting chain between two adjacent rubber fenders. Through the two end metal parts (i.e. the rotating parts at both ends) and the middle swivel, a total of three connection nodes that can rotate freely 360 degrees, the technical effect of the adjacent rubber fender bodies rotating freely in the sea with the rise and fall of the waves without colliding with each other is achieved.

[0022] In summary, compared with the prior art, the present invention has at least one of the following beneficial technical effects: This invention improves the original single metal end piece of the rubber fender by replacing it with two independent metal components: a support and a rotating frame, connected by a pivot shaft. This allows the rotating frame to rotate freely 360 degrees relative to the support. This structural design enables the mooring rope connected to the rotating frame to rotate freely relative to the fender body when the rubber fender changes attitude under the action of waves. This effectively prevents entanglement between the fender and the mooring rope, and also dilutes and releases the torque exerted on the mooring rope by the fender's movement with the waves, significantly reducing the torsional stress on the mooring rope and extending the service life of the mooring system.

[0023] This invention innovatively incorporates a swivel ring in the middle section of the chain. This swivel ring consists of a pull ring and a pin ring, allowing for 360-degree free rotation between them. When two or more rubber fenders are placed side by side, adjacent fenders are connected by a chain, with the swivel ring in the middle section providing an additional degree of rotational freedom. Combined with the rotating parts at both ends, each fender end connection structure has three connection nodes that can rotate freely 360 degrees. This multi-node rotation design allows adjacent rubber fenders to move independently and in a coordinated manner under the influence of waves, effectively preventing collisions, compression, and friction between adjacent fenders. This protects the fender body and further disperses and eliminates torsional stress on the chain.

[0024] This invention employs a combined threaded and welded connection method between the shaft and the rotating frame, significantly improving the connection strength between the shaft and the upper metal component (rotating frame), ensuring that it will not loosen or break under enormous tensile forces. The ear plates utilize a slanted layout, narrower at the top and wider at the bottom, optimizing stress distribution and improving their bending resistance and structural stability under tensile loads. The four connecting plates are evenly distributed on the ring in a frustum-shaped arrangement, and the combination of grooved and L-shaped contact surfaces effectively increases the contact area of ​​the welding zone, improving the overall structure's load-bearing capacity and fatigue life.

[0025] This invention incorporates multiple anti-loosening devices at key fastening points. All nuts (first nut, second nut, and third nut) are equipped with corresponding locking bolts to prevent loosening due to vibration or repeated stress during use. The end of the first bolt uses a combination of a bolt pin and a bolt pin nut instead of a traditional cotter pin, providing higher bending strength and better anti-loosening effect. A shaft pin and a shaft pin nut are also provided at the end of the shaft to further ensure the reliability of axial positioning.

[0026] The present invention incorporates a copper sleeve in the critical break-in area (between the shaft and the through hole of the circular plate). The copper sleeve has excellent friction-reducing and wear-resistant properties, which can effectively reduce the frictional resistance between the shaft and the support, ensuring smooth rotation. At the same time, as a replaceable wear part, the copper sleeve facilitates later maintenance and replacement, reducing the total life cycle cost.

[0027] This invention uses a stowed anchor chain as the main component of the chain. The stowed anchor chain features high tensile strength and strong load-bearing capacity, forming a high-strength load transfer path together with the swivel and rotating parts. Through reasonable size design and material selection, the fender end connection structure of this invention fully meets the load-bearing capacity requirements of the end connectors for rubber fenders during mooring operations.

[0028] The fender end connection structure of the present invention is reasonably designed, compact, and easy to install. It has good versatility and interchangeability and can be applied to various types and specifications of rubber fenders, including but not limited to inflatable rubber fenders, solid rubber fenders, and foam-filled rubber fenders. It has broad market application prospects and significant economic benefits. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0030] Figure 2 This is an exploded structural diagram of the present invention.

[0031] Figure 3 This is an exploded structural diagram of the rotating part of the present invention.

[0032] Figure 4 This is a schematic diagram of the overall structure of the support for the rotating part of the present invention.

[0033] Figure 5 This is an exploded structural diagram of the rotating frame of the rotating part of the present invention.

[0034] Reference numerals: 100, Rotating part; 110, Support; 111, Ring; 112, Circular plate; 112a, Through hole; 112b, Copper sleeve; 113, Connecting plate; 113a, Groove contact surface; 113b, L-shaped contact surface; 114, Pad; 120, Rotating frame; 121, Base plate; 122, Ear plate; 123, Rotating shaft; 123a, Smooth surface part; 123b, External thread section; 124, Reinforcing plate; 125, ... 1. Bolt; 126. First nut; 126a. First nut locking bolt; 127. Bolt pin; 128. Bolt pin nut; 129. Second nut; 129a. Second nut locking bolt; 130. Third nut; 130a. Third nut locking bolt; 131. Shaft pin; 132. Shaft pin nut; 200. Chain; 210. Stuck anchor chain; 220. Swivel; 221. Pull ring; 222. Pin ring. Detailed Implementation

[0035] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0036] In the description of this application, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0037] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0038] First, the overall concept and technical approach of this invention are explained. This invention aims to resolve a core technical contradiction in existing rubber fender end metal connectors: under limited dimensional constraints, it must ensure sufficient tensile strength to meet the enormous load requirements of mooring operations, while also achieving 360-degree free rotation to prevent the fender from tangling with the mooring ropes and to release torsional stress, and simultaneously meet the special requirement of avoiding collisions when multiple rubber fenders are used side-by-side. To solve this series of mutually constraining technical problems, this invention proposes a systematic solution: functional decoupling and structural reconstruction of the originally single-function end metal component, forming a composite link structure with multiple functional modules working collaboratively, including a support, a rotating frame, a swivel, and a secured anchor chain. Specifically, the end metal component is split into two independent parts: a support for fixing and a rotating frame for rotating, connected by a pivot to achieve the first 360-degree rotation; a swivel consisting of a pull ring and a pin ring is introduced in the middle of the connecting chain to achieve the second 360-degree rotation; the secured anchor chain between the rotating parts at both ends and the swivel allows for flexible swinging while bearing tensile force. The three rotating nodes mentioned above work together to form a fender end connection system with high degree of freedom, high load-bearing capacity, and high fatigue resistance.

[0039] The technical solution of the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0040] Example 1 Please see Figures 1 to 5 This embodiment provides a fender end connection structure. This connection structure is mainly used to connect the end face of the rubber fender to the mooring rope (or mooring anchor point), and is a key component of the rubber fender that bears and transmits loads during ship mooring operations.

[0041] like Figure 1 As shown, the fender end connection structure of the present invention mainly includes a chain 200 and rotating parts 100 respectively connected to both ends of the chain 200. The rotating part 100 includes a bracket 110 and a rotating frame 120 rotatably connected to the bracket 110. The rotating frame 120 can rotate freely 360 degrees relative to the bracket 110, and is connected to one end of the chain 200. The bottom of the bracket 110 is fixedly connected to the end face of the rubber fender by fasteners (such as bolts, screws, etc.), and the end of the chain 200 away from the rubber fender is connected to the mooring rope or mooring anchor point. Thus, a complete and reliable load transfer path is formed from the end face of the rubber fender to the mooring anchor point.

[0042] The structure of chain 200 is as follows Figure 2As shown. Chain 200 includes a swivel 220 and a studded anchor chain 210 connected to both ends of the swivel 220. The end of the studded anchor chain 210 away from the swivel 220 is connected to the corresponding rotating frame 120. The studded anchor chain 210 is a type of chain with high tensile strength known in the art. Anchor chains consist of ordinary chain links, connecting chain links, connecting shackles, swivels, etc. According to the structure of the anchor chain, they are divided into studded and studless types. Studded chains have high tensile strength, and studded anchor chains are generally used on ships. This invention uses the studded anchor chain 210 as the main component of chain 200 to fully utilize its excellent tensile load-bearing capacity and ensure the safety and reliability of the entire link structure when bearing mooring loads. The specifications of the studded anchor chain 210 (such as chain link diameter, material grade, etc.) can be selected according to the design load and operating conditions of the rubber fender. Generally, welded anchor chains or cast steel anchor chains with diameters ranging from 16mm to 70mm can be selected.

[0043] The specific structure of the swivel ring 220 is as follows: Figure 2 As shown. The swivel 220 includes a pull ring 221 and a pin ring 222 rotatably connected to one end of the pull ring 221. The pin ring 222 is capable of 360-degree free rotation relative to the pull ring 221. The end of the pin ring 222 away from the pull ring 221 is connected to one of the stowed anchor chains 210 (e.g., by engaging with the end link of the stowed anchor chain 210 through a ring hole in the pin ring 222 itself), and the end of the pull ring 221 away from the pin ring 222 is connected to another stowed anchor chain 210 (e.g., by engaging with the end link of another stowed anchor chain 210 through a ring hole in the pull ring 221 itself). In the field of anchor chain technology, the swivel's function is to prevent excessive twisting of the anchor chain during anchoring. This invention innovatively introduces the swivel 220 into the end link structure of the rubber fender, making it a key rotating node connecting the middle section of the chain 200. This design enables the chain 200 to release and eliminate torsional stress. When the rubber fender undergoes torsional motion under the action of waves, the swivel ring 220 can automatically rotate to absorb and counteract the torsional motion, preventing torsional stress from being transmitted and accumulated along the chain 200 to both ends.

[0044] The specific structure of the rotating part 100 will be described in detail below.

[0045] like Figure 3 and Figure 4As shown, the bracket 110 is the component in the rotating part 100 that is directly connected to the end face of the rubber fender. It undertakes the basic function of fixing the entire connecting structure to the end of the fender and provides rotational support for the rotating frame 120. The bracket 110 includes a ring 111, a circular plate 112, and four connecting plates 113 fixedly connected between the ring 111 and the circular plate 112. The circular plate 112 is located above the ring 111 and is coaxially arranged with the ring 111. The outer diameter of the circular plate 112 is smaller than the outer diameter of the ring 111. The bottom end of the connecting plate 113 is fixedly connected to the ring 111 by opening a groove-shaped contact surface 113a, and the top end of the connecting plate 113 is fixedly connected to the side wall and bottom edge of the circular plate 112 by opening an L-shaped contact surface 113b. The four connecting plates 113 are evenly distributed on the ring 111 (i.e., the included angle between the centers of adjacent connecting plates 113 is 90 degrees), so that the bracket 110 has an overall frustum-shaped structure.

[0046] like Figure 4 As shown, the frustum-shaped structure of the support 110 has several technical advantages. First, the frustum-shaped conical structure can evenly distribute the axial tensile force acting on the circular plate 112 to the larger diameter bottom ring 111, which helps to reduce the stress concentration at the root of the connecting plate 113 and improve the overall load-bearing capacity. Second, the frustum-shaped structure has good self-stability and can effectively resist the effects of lateral forces and eccentric loads. Third, the evenly distributed layout of the four connecting plates 113 ensures that the force performance of the support 110 is uniform and symmetrical in all directions, avoiding the problem of anisotropy in structural stiffness.

[0047] The grooved contact surface 113a at the bottom of the connecting plate 113 refers to a groove structure with a certain depth and width formed at the edge where the connecting plate 113 contacts the ring 111. This groove increases the welding contact area between the connecting plate 113 and the ring 111, allowing the weld to penetrate deep into the groove, thus improving welding strength and connection reliability. The L-shaped contact surface 113b at the top of the connecting plate 113 refers to an L-shaped stepped surface processed at the top of the connecting plate 113 in the area where it contacts the circular plate 112. This L-shaped stepped surface can simultaneously contact the side wall and bottom edge of the circular plate 112, further increasing the welding contact area and ensuring the firmness of the connection between the connecting plate 113 and the circular plate 112. During the manufacturing process, the four connecting plates 113 are fixed to the ring 111 and the circular plate 112 using a full welding process to fully guarantee the connection strength and structural rigidity of the welding area.

[0048] A through hole 112a is provided on the circular plate 112, and a copper sleeve 112b is fixedly installed in the through hole 112a. Figure 4As shown, the copper sleeve 112b is fixed in the through hole 112a by interference fit or welding. The function of the copper sleeve 112b is to provide a friction-reducing and wear-resistant rotating support surface for the rotating shaft 123. The copper sleeve 112b has good self-lubricating and wear-resistant properties, which can effectively reduce the coefficient of friction between the rotating shaft 123 and the circular plate 112, reduce frictional resistance and wear during rotation, and ensure smooth rotation. At the same time, as a replaceable wear component, the copper sleeve 112b can be easily replaced if wear occurs after long-term use, without having to replace the entire bracket 110, thereby reducing maintenance costs and total life cycle costs.

[0049] like Figure 5 As shown, the rotating frame 120 includes a base plate 121, two ear plates 122 integrally formed and fixedly connected to the base plate 121, and a rotating shaft 123 fixedly connected to the end of the base plate 121 away from the ear plates 122. The base plate 121 preferably has a flat plate structure, providing a stable mounting base for the ear plates 122 and the rotating shaft 123. A first bolt 125 and a first nut 126 threadedly connected to the two ear plates 122 are connected through the base plate 122. One end of the studded anchor chain 210 is sleeved on the first bolt 125 (i.e., on the section of the first bolt 125 located between the two ear plates 122), and the studded anchor chain 210 is detachably connected to the rotating frame 120 through the tightening action of the first bolt 125 and the first nut 126. This connection method ensures the reliability of the connection and facilitates the disassembly and replacement of the chain 200 when needed.

[0050] The ear plate 122 is a key load-bearing component in this embodiment, bearing the tension transmitted from the chain 200. To improve the structural stability and bending resistance of the ear plate 122 under tensile loads, the present invention optimizes its design. First, reinforcing plates 124 are fixedly connected to both sides between the two ear plates 122, with the bottom of the reinforcing plates 124 fixedly connected to the base plate 121. The reinforcing plates 124 effectively enhance the lateral stiffness of the ear plates 122, preventing lateral bending deformation under heavy loads. Second, the ear plates 122 are designed with a slanted layout, narrower at the top and wider at the bottom; that is, the upper width of the ear plate 122 is less than the lower width. Viewed from the side, the front and rear edges of the ear plates 122 form an inwardly sloping line shape, such as... Figure 5 As shown. This slanted layout makes the stress-bearing cross section of the ear plate 122 gradually increase from the top to the root, resulting in a more reasonable stress distribution and effectively improving the bending resistance and load-bearing safety factor of the root of the ear plate 122.

[0051] The rotating shaft 123 is the core component connecting the rotating frame 120 and the support 110. It must ensure that the rotating frame 120 can rotate smoothly 360 degrees relative to the support 110, while also withstanding the enormous axial tensile force transmitted from the chain 200. The rotating shaft 123 and the base plate 121 are connected by a composite connection method using threads and welding. Specifically, the base plate 121 has a threaded hole, and the end of the rotating shaft 123 is machined with a matching external thread. The rotating shaft 123 is first screwed into the threaded hole in the base plate 121 to form a threaded connection. Then, circumferential welding is applied to the outer circumference of the threaded connection to firmly fix the rotating shaft 123 and the base plate 121 together. This composite connection method of threads and welding fully utilizes the advantages of both connection methods: the threaded connection provides precise axial positioning and initial connection strength, while welding further enhances the torsional resistance and fatigue resistance of the connection, ensuring that it will not loosen or break under long-term alternating loads.

[0052] A partially threaded section 123b is formed on the outer wall of the end of the rotating shaft 123 furthest from the base plate 121. The remaining part of the rotating shaft 123 is a smooth surface portion 123a. After one end of the rotating shaft 123 passes through the copper sleeve 112b on the circular plate 112, a second nut 129 and a third nut 130 are sequentially threaded onto the threaded section. The second nut 129 and the third nut 130 axially limit the rotating shaft 123 to be rotatably fixed on the bracket 110. A clearance fit (e.g., a clearance fit of H7 / f6 or H8 / f7 grade) is used between the smooth surface portion 123a and the inner hole of the copper sleeve 112b, allowing the rotating shaft 123 to rotate flexibly within the copper sleeve 112b, realizing the 360-degree free rotation of the rotating frame 120 relative to the bracket 110.

[0053] To ensure that the fastening components do not loosen during long-term operation, the present invention is equipped with a multi-layered anti-loosening device.

[0054] like Figure 3 As shown, a bolt pin 127 and a mating bolt pin nut 128 are installed through the side wall of the threaded end of the first bolt 125 extending from the first nut 126. The bolt pin 127 passes through a pre-set radial through hole on the shank of the first bolt 125, and the bolt pin nut 128 is screwed onto the threaded end of the bolt pin 127. The tight fit between the bolt pin 127 and the bolt pin nut 128 prevents the first nut 126 from loosening or falling off due to vibration or repeated stress. Compared with conventionally used cotter pins, the combination of bolt pin 127 and bolt pin nut 128 has higher structural strength and a more reliable anti-loosening effect. In addition, a first nut locking bolt 126a is also installed on the side wall of the first nut 126. The first nut locking bolt 126a is screwed in radially along the first nut 126, and its end abuts against the threaded surface of the first bolt 125, locking the first nut 126 in a tightened position through friction.

[0055] like Figure 3 As shown, a second nut locking bolt 129a is installed on the side wall of the second nut 129 to lock the second nut 129 in its tightened position; a third nut locking bolt 130a is installed on the side wall of the third nut 130 to lock the third nut 130 in its tightened position. The working principle of the second nut locking bolt 129a and the third nut locking bolt 130a is the same as that of the first nut locking bolt 126a, both achieving the anti-loosening function by generating friction through radial tightening. The second nut 129 and the third nut 130 adopt a double-nut tightening structure, with the two nuts pressing against each other, which itself has a certain anti-loosening effect. Combined with their respective locking bolts, a triple anti-loosening guarantee is formed, ensuring the absolute reliability of axial positioning.

[0056] like Figure 3 As shown, a shaft pin 131 and a mating shaft pin nut 132 are installed through the side wall of the threaded end of the shaft 123 that passes through the third nut 130. The engagement of the shaft pin 131 and the shaft pin nut 132 effectively prevents the second nut 129 and the third nut 130 from axially moving during operation, providing a final safety guarantee for the double-nut locking structure.

[0057] Furthermore, such as Figure 3 As shown, a washer 114 is provided between the second nut 129 and the copper sleeve 112b, and the washer 114 is sleeved on the rotating shaft 123. The function of the washer 114 is to increase the contact area between the second nut 129 and the copper sleeve 112b, distribute the axial load, protect the end face of the copper sleeve 112b from excessive local compressive stress, and extend the service life of the copper sleeve 112b. The washer 114 can be made of a metal material with excellent wear resistance (such as quenched and tempered 45 steel) or a high-strength composite material.

[0058] Example 2 This embodiment focuses on describing the application and technical effects of the fender end connection structure of the present invention when two or more rubber fenders are placed side by side.

[0059] When two or more rubber fenders need to be placed side by side, adjacent rubber fenders are connected by the fender end link structure at their respective ends. Specifically, the rotating part 100 at the right end of the left rubber fender is connected to one end of the chain 200, and the other end of the chain 200 is connected to the rotating part 100 at the left end of the right rubber fender. This connection is repeated to form a continuous fender connection chain.

[0060] In the connecting chain 200 between adjacent rubber fenders, the swivel 220 is located in the middle section of the chain 200. Through a reasonable design of the chain 200 length, the distance between the metal parts at the ends of adjacent rubber fenders (i.e., the rotating parts 100 at both ends) is controlled at about 90 centimeters. This distance ensures sufficient movement space between adjacent fenders, avoids mutual interference between the fender bodies, and prevents the chain 200 from being too long, which would lead to excessive swing amplitude and difficulty in control.

[0061] In the connected state, each of the two rotating parts 100 in the end link structure of each fender provides one point of 360-degree free rotation (i.e., rotation of the rotating frame 120 relative to the support 110), and the swivel ring 220 in the middle section of the chain 200 provides a third point of 360-degree free rotation (i.e., rotation of the pin ring 222 relative to the pull ring 221). Therefore, for the connection between two adjacent rubber fenders, there are a total of three connection nodes that can rotate 360 ​​degrees freely.

[0062] The collaborative working mechanism of these three rotating nodes is as follows: When waves and swells occur on the sea surface, the rubber fenders rise and fall with the waves, constantly changing their posture. The rotating nodes at both ends of the rotating section 100 allow the chain 200 at each end of the fender to rotate freely relative to the fender body, thus avoiding the entanglement problem caused by relative torsion between the chain 200 and the fender body. At the same time, it converts the torsional motion generated by the fender movement into rotational motion, diluting and releasing torsional stress. The rotating node of the middle swivel 220 further absorbs and cancels out any relative torsional motion that may exist between the left and right sections of the chain 200, preventing torsional stress from accumulating along the entire chain 200. The three rotating nodes cooperate with each other to form a connection system with a high degree of freedom of motion chain, allowing adjacent rubber fenders to rotate independently and in coordination freely in the sea as they rise and fall with the waves, without ever colliding with each other.

[0063] It should be specifically noted that the phrase "never colliding with each other" in this invention refers to the fact that under normal operating conditions, due to the sufficient degrees of freedom provided by the three rotating nodes, the relative movement between adjacent rubber fenders is always within a safe range, and direct contact and impact will not occur between the fender bodies. In extremely harsh sea conditions (such as typhoons, giant waves, etc.), the fender system may exceed its design operating conditions, and the resulting collision risk is not within the normal protection scope of this invention. Those skilled in the art can reasonably select the size specifications of the rubber fenders, the length of the chain 200, and the strength grade of each structural component according to the actual operating environment and design specifications to ensure safety under predetermined operating conditions.

[0064] Example 3 This embodiment provides preferred material selection schemes and processing technology suggestions for each component of the fender end connection structure of the present invention.

[0065] For the ring 111, circular plate 112, and connecting plate 113 of the bracket 110, it is recommended to use high-quality carbon structural steel (such as Q345B, 45 steel, etc.) or low-alloy high-strength structural steel (such as Q420, Q460, etc.). For applications requiring higher loads, alloy structural steel (such as 40Cr, 35CrMo, etc.) can be used and tempered to improve comprehensive mechanical properties. The thickness of the connecting plate 113 is recommended to be between 8mm and 20mm, specifically determined based on design load calculations. The grooved contact surface 113a and L-shaped contact surface 113b are recommended to be machined using CNC milling or wire cutting processes to ensure dimensional accuracy and welding quality.

[0066] For the base plate 121, ear plate 122, and reinforcing plate 124 of the rotating frame 120, it is recommended to use structural steel of the same or higher strength grade as the support 110. As the core load-bearing component, the rotating shaft 123 is recommended to be made of medium carbon alloy steel (such as 40Cr, 42CrMo, etc.) after quenching and tempering, and then precision machined to achieve a surface hardness of HRC28-32. The threaded portion can be rolled to strengthen it and improve fatigue strength. The copper bushing 112b is recommended to be made of cast copper alloy (such as ZCuSn10Pb1, ZCuAl10Fe3, etc.), as this type of material has good friction-reducing and wear-resistant properties. The pad plate 114 is recommended to be made of 45 steel after quenching and tempering.

[0067] For the saddle anchor chain 210, it is recommended to use welded or cast steel anchor chains conforming to GB / T 549-2008 standards or relevant specifications of the International Association of Classification Societies (IACS), with materials such as CM490 and CM690 marine anchor chain steel. For the swivel 220, the pull ring 221 and pin ring 222 are recommended to be manufactured using forging technology, with materials matching the anchor chain steel of the saddle anchor chain 210 to ensure overall strength and toughness. The first bolt 125 is recommended to be a high-strength bolt with a performance grade not lower than 8.8; for critical applications, grades 10.9 or 12.9 can be used. The first nut 126, second nut 129, and third nut 130 should be selected with performance grades matching the bolts.

[0068] All steel structural components are recommended to undergo anti-corrosion treatment, such as hot-dip galvanizing, spraying with anti-corrosion coatings, or manufacturing with stainless steel, to meet the long-term use requirements of marine environments. Welding processes include CO2 gas shielded welding or manual arc welding, using welding rods or wires of a grade compatible with the base metal. Post-weld non-destructive testing of the weld should be performed to ensure weld quality.

[0069] Example 4 This embodiment provides an assembly method and installation and usage steps for the fender end link structure of the present invention.

[0070] The assembly steps are as follows: Step 1: Manufacturing Preparation. Following the design drawings, complete the machining and surface treatment of each component, including bracket 110, rotating frame 120, and swivel ring 220, and check whether the dimensions and geometric tolerances of each component meet the design requirements.

[0071] Step 2: Assembly of bracket 110 and rotating frame 120. Press or weld the copper sleeve 112b into the through hole 112a of the circular plate 112; fit the pad 114 onto the rotating shaft 123; pass the rotating shaft 123 through the inner hole of the copper sleeve 112b, so that the smooth surface part 123a mates with the copper sleeve 112b; screw the second nut 129 and the third nut 130 sequentially onto the external thread section 123b of the rotating shaft 123; adjust the axial position of the second nut 129 and the third nut 130 to ensure that the rotating shaft 123 can rotate flexibly without obvious axial movement; tighten the second nut locking bolt 129a and the third nut locking bolt 130a respectively; insert the rotating shaft pin 131 into the end of the rotating shaft 123 and tighten the rotating shaft pin nut 132.

[0072] Step 3: Connecting the chain 200 to the rotating frame 120. Place the end link of the anchor chain 210 between the two lugs 122 of the rotating frame 120; insert the first bolt 125; screw in the first nut 126 and tighten it to the specified torque; tighten the first nut locking bolt 126a; insert the bolt pin 127 into the end of the first bolt 125 and tighten the bolt pin nut 128.

[0073] Step 4: Overall Inspection. Check whether each rotating part can rotate freely (360 degrees without jamming), whether each fastener is secure and reliable, and whether each anti-loosening device is installed in place.

[0074] The installation and usage steps are as follows: Step 1: Secure the ring 111 of the bracket 110 to the end flange or end plate of the rubber fender using fasteners (such as bolts, studs, etc.).

[0075] Step 2: For applications involving a single rubber fender, connect the stopped anchor chain 210 at the other end of chain 200 to the mooring rope or dock mooring point.

[0076] Step 3: When multiple rubber fenders are used side by side, connect the end links of adjacent fenders with chains 200 and adjust the length of chains 200 so that the distance between the ends of adjacent fenders is about 90 centimeters.

[0077] Step 4: Check that all connections are secure and all rotating parts are flexible. Once confirmed to be in order, the device can be put into use.

[0078] Example 5 This embodiment illustrates the superiority of the present invention's technical solution over existing technologies through comparative experimental data.

[0079] Three groups of CY1500 type inflatable rubber fenders of the same specifications were selected and compared using the fender end connection structure of this invention (test group), existing fixed end metal parts (control group 1), and end connectors with only a single rotating node (control group 2). The tests were conducted in a wave pool simulating a marine environment, with wave parameters of 1.5 meters in height and 6 seconds in period, and the test duration was 72 hours. During the tests, the number of fender-mooring rope entanglements, the number of collisions between adjacent fenders, and the maximum torsional stress of the mooring rope were recorded for each group.

[0080] The test results showed that during the 72-hour test, the test group (the scheme of this invention) experienced 0 instances of fender-mooring rope entanglement and 0 instances of adjacent fender collisions. The maximum torsional stress of the mooring rope was reduced by approximately 78% compared to control group one and by approximately 52% compared to control group two. Control group one experienced 14 instances of fender-mooring rope entanglement and 22 instances of adjacent fender collisions. Control group two experienced 3 instances of fender-mooring rope entanglement and 8 instances of adjacent fender collisions.

[0081] The test results show that the fender end link structure provided by the present invention has significant advantages in preventing the fender from getting tangled with the mooring rope, avoiding collisions between adjacent fenders, and releasing the torsional stress of the mooring rope, which fully demonstrates the beneficial effects of the technical solution of the present invention.

[0082] The implementation principle of this invention is as follows: This invention discloses a fender end connection structure, belonging to the technical field of ship mooring equipment. The structure includes a chain and rotating parts connected to both ends of the chain; the rotating parts include a bracket and a rotating frame rotatably connected to the bracket, the rotating frame being able to rotate freely 360 degrees relative to the bracket; the chain includes a swivel and a stopped anchor chain connected to both ends of the swivel; the swivel includes a pull ring and a pin ring rotatably connected to one end of the pull ring, the pin ring being able to rotate freely 360 degrees relative to the pull ring. This invention improves the original single rubber fender end metal part into two independent, separate components: a bracket and a rotating frame, with a pivot in the middle enabling 360-degree free rotation, and introduces a swivel in the middle section of the chain to form a second rotating node. This structure effectively avoids entanglement between the fender and the mooring line, dilutes the torque generated by the fender movement on the mooring line, and effectively prevents collisions between adjacent fenders when multiple fenders are used side-by-side, significantly improving the safety and lifespan of the fender.

[0083] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A fender end connection structure, characterized in that, include: Chain (200), and rotating parts (100) respectively connected to both ends of the chain (200); The rotating part (100) includes a bracket (110) and a rotating frame (120) rotatably connected to the bracket (110). The rotating frame (120) can rotate freely 360 degrees relative to the bracket (110). The rotating frame (120) is connected to one end of the chain (200). The chain (200) includes a swivel (220) and a stop anchor chain (210) connected to both ends of the swivel (220), with the end of the stop anchor chain (210) away from the swivel (220) connected to the corresponding rotating frame (120); The swivel (220) includes a pull ring (221) and a pin ring (222) rotatably connected to one end of the pull ring (221). The pin ring (222) can rotate freely 360 degrees relative to the pull ring (221). The end of the pin ring (222) away from the pull ring (221) is connected to one of the studded anchor chains (210), and the end of the pull ring (221) away from the pin ring (222) is connected to the other studded anchor chain (210).

2. The fender end connection structure according to claim 1, characterized in that, The bracket (110) includes a ring (111), a circular plate (112), and four connecting plates (113) fixedly connected between the ring (111) and the circular plate (112). The circular plate (112) is located above the ring (111) and is coaxially arranged with the ring (111). The outer diameter of the circular plate (112) is smaller than the outer diameter of the ring (111). The bottom end of the connecting plate (113) is fixedly connected to the ring (111) by opening a groove-shaped contact surface (113a), and the top end of the connecting plate (113) is fixedly connected to the side wall and bottom edge of the circular plate (112) by opening an L-shaped contact surface (113b). The four connecting plates (113) are evenly distributed on the ring (111), so that the bracket (110) has a frustum-shaped structure as a whole.

3. The fender end connection structure according to claim 2, characterized in that, A through hole (112a) is provided on the circular plate (112), and a copper sleeve (112b) is fixedly installed in the through hole (112a). The rotating frame (120) includes a base plate (121), two ear plates (122) integrally formed and fixedly connected to the base plate (121), and a rotating shaft (123) fixedly connected to one end of the base plate (121) away from the ear plates (122). A first bolt (125) and a first nut (126) threadedly connected to the two ear plates (122) are connected through the two ear plates (122), and one end of the stop anchor chain (210) is sleeved on the first bolt (125); The outer wall of the shaft (123) away from the base plate (121) has a partial external thread section (123b). After the shaft (123) passes through the copper sleeve (112b) on the circular plate (112), a second nut (129) and a third nut (130) are sequentially threaded onto the thread section.

4. The fender end connection structure according to claim 3, characterized in that, A reinforcing plate (124) is fixedly connected to each side between the two ear plates (122), and the bottom of the reinforcing plate (124) is fixedly connected to the base plate (121); The ear plate (122) is designed with a slanted layout that is narrower at the top and wider at the bottom, meaning that the upper width of the ear plate (122) is smaller than the lower width.

5. The fender end connection structure according to claim 3, characterized in that, The first bolt (125) has a bolt pin (127) and a bolt pin nut (128) that mates with it installed on the side wall of the threaded end of the first nut (126). A first nut locking bolt (126a) is installed on the side wall of the first nut (126).

6. The fender end connection structure according to claim 3, characterized in that, A second nut locking bolt (129a) is installed on the side wall of the second nut (129). The third nut (130) is fitted with a third nut locking bolt (130a) on its side wall.

7. The fender end connection structure according to claim 6, characterized in that, The rotating shaft (123) has a rotating shaft pin (131) and a rotating shaft pin nut (132) that cooperates with it installed on the side wall of the threaded end of the third nut (130).

8. The fender end connection structure according to claim 3, characterized in that, A washer (114) is provided between the second nut (129) and the copper sleeve (112b), and the washer (114) is sleeved on the rotating shaft (123); The smooth surface portion (123a) of the rotating shaft (123) and the inner hole of the copper sleeve (112b) are fitted with a clearance fit.

9. The fender end connection structure according to claim 3, characterized in that, The rotating shaft (123) and the base plate (121) are connected by a composite connection method of threaded connection and welding fixation; The groove-shaped contact surfaces (113a) and L-shaped contact surfaces (113b) between the four connecting plates (113) and the ring (111) and the circular plate (112) are fixed by full welding.

10. A fender end connection structure according to any one of claims 1 to 9, characterized in that, The bottom of the bracket (110) is fixedly connected to the end face of the rubber fender by fasteners, and the rotating frame (120) is rotatably connected to the bracket (110) by the rotating shaft (123); When two or more rubber fenders are placed side by side, the adjacent rubber fenders are connected by the fender end link structure at their respective ends. Each fender end link structure has three 360-degree free rotation nodes, namely the rotation nodes of the two end rotating parts (100) and the rotation node of the middle rotating ring (220), so that the adjacent rubber fenders can rotate freely without colliding with each other.

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