High-tensile mechanical locking structure optical fiber patch cord tail fiber

Abstract

This invention relates to the field of optical fiber communication technology and discloses a high-tensile-strength mechanical locking structure for optical fiber patch cord pigtails, including a tail sleeve, a rivet ring, a rear sleeve, a spring, a ceramic ferrule, an outer nut, a front sleeve, and an optical fiber. A mechanical locking assembly is provided between the tail sleeve and the rear sleeve. This assembly includes an elastic clamping structure and a wedge-tightening structure. The invention drives the elastic clamping piece to radially contract through the engagement of the wedge-tightening surface and the inclined surface of the wedge-tightening cavity. This, combined with multi-level ribs, forms a graded positioning and clamping effect on the optical fiber protective layer. At the same time, the hook and the annular locking groove achieve axial reverse locking. The multiple ribs on the inner wall of the tail sleeve form a segmented buffer structure. This design achieves a purely mechanical full-link tensile locking, allowing the axial tensile force to be independently borne by the mechanical structure. This avoids the curing defects and aging failure problems of traditional methods and significantly improves the connection reliability and tensile durability of optical fiber patch cord pigtails under complex working conditions such as vibration and tension.

Description

Technical Field

[0001] This invention relates to the field of optical fiber communication technology, specifically to a high tensile strength mechanical locking structure optical fiber patch cord pigtail. Background Technology

[0002] With the rapid development of optical communication technology, fiber optic patch cords and pigtails, as crucial connecting components for optical signal transmission, equipment docking, and optical path conversion between optical communication devices, are widely used in data centers, communication equipment rooms, fiber optic distribution frames, communication base stations, and building integrated cabling. The most fundamental difference between fiber optic patch cords and pigtails lies in the number of connectors. Patch cords have connectors at both ends, while pigtails have a connector at only one end, with the other end being bare fiber. Fiber optic patch cords and pigtails typically consist of a connector and an optical fiber. Due to the inherent fragility of optical fibers, and because the connection between the fiber and the connector directly affects the continuity of optical path transmission, reliable axial locking and tensile strength bearing are necessary between the fiber and the connector during field cabling, equipment installation, and long-term operation. This ensures that external tensile loads are absorbed and distributed through components such as the pigtail sleeve and locking structure, preventing direct tension on the connection between the fiber and the connector. Therefore, equipping fiber optic patch cord pigtails with a mechanical locking structure that has high tensile strength and reliable locking performance can improve the mechanical stability of the pigtail connection and adapt to the complex stress conditions during computer room construction, equipment maintenance, and long-term operation.

[0003] Currently, SC and FC type fiber optic patch cords and pigtails typically employ a combination of component assembly and adhesive curing during assembly to secure the fiber optic cable, ferrule, and tail sleeve, supplemented by simple snap-fit, limiting, or clamping structures for mechanical positioning. When subjected to axial forces such as cable dragging, equipment weight pulling, cabinet vibration, and material deformation caused by temperature changes, these traditional structures rely primarily on the adhesive bonding area and a relatively simple tail sleeve limiting structure to bear the load. They lack a mechanical locking structure capable of multi-area clamping of the fiber's outer protective layer and progressively distributing axial tension, making it easy for external tension to be concentrated at the fiber-connector connection. Furthermore, the locking degree of traditional mechanical limiting structures is limited, and under long-term stress and vibration, slight axial slippage, loosening, or even detachment of the fiber relative to the connector can easily occur, leading to decreased connection stability, fluctuations in optical signal transmission loss, or even communication interruption. In addition, when large instantaneous tensile forces act directly on the adhesive bonding interface, they can easily cause fatigue, peeling, or detachment of the adhesive layer, further reducing the reliability of the fixation between the fiber and the connector. Therefore, existing fiber optic patch cord pigtails suffer from insufficient mechanical locking capacity, poor tensile load dispersion, and low long-term locking stability, making it difficult to meet the reliability requirements of pigtail connections in complex construction environments and long-term stable communication processes. To address this, we propose a fiber optic patch cord pigtail with a high tensile mechanical locking structure. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a high-tensile-strength mechanically locked fiber optic patch cord pigtail, solving the aforementioned problems.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: a high tensile strength mechanical locking structure fiber optic patch cord pigtail, comprising an end connector and an optical fiber consisting of a tail sleeve, a rivet ring, a rear sleeve, a spring, a ceramic ferrule, an outer nut, and a front sleeve. The ceramic ferrule is installed inside the front sleeve, and an outer nut is fitted on the outer side of the front sleeve, with the outer nut being movably connected to the front sleeve. A rear sleeve is installed behind the ceramic ferrule, and the rear sleeve and the front sleeve are threaded together. A spring is installed between the ceramic ferrule and the rear sleeve. A rivet ring is installed behind the rear sleeve, and a tail sleeve is installed behind the rivet ring. An optical fiber is fixedly installed on the ceramic ferrule, and the tail sleeve is fitted on the outer side of the outer protective layer of the optical fiber.

[0006] A mechanical locking assembly is provided between the tail sleeve and the rear sleeve. The mechanical locking assembly includes an elastic clamping structure and a wedge clamping structure. The elastic clamping structure is disposed on the rivet ring, and the wedge clamping structure and the elastic clamping structure cooperate with each other.

[0007] Preferably, the rivet ring is a stepped cylindrical annular structure coaxial with the optical fiber, the rear end of the rivet ring forms a continuous annular segment, and the front end of the rivet ring forms an elastic clamping structure for clamping the outer protective layer of the optical fiber.

[0008] The elastic clamping structure includes elastic clamping pieces and partition grooves. Multiple elastic clamping pieces are arranged at intervals along the circumference of the rivet ring. Adjacent elastic clamping pieces are separated from each other by partition grooves, so that each elastic clamping piece can generate independent radial elastic deflection relative to the main body of the rivet ring.

[0009] Preferably, the elastic clamping piece is formed by partially cutting the ring wall of the rivet ring. Each elastic clamping piece is an arc-shaped sheet structure extending along the axial direction of the rivet ring. The inner side of the elastic clamping piece is an arc surface coaxial with the rivet ring. The inner side of the elastic clamping piece faces the outer protective layer of the optical fiber, and the outer side faces the inner wall of the tail sleeve.

[0010] Preferably, the dividing groove extends along the axial direction of the rivet ring, with the front end of the dividing groove penetrating the corresponding end of the rivet ring and the rear end of the dividing groove not penetrating the corresponding end of the rivet ring, so that the elastic clamping piece remains integrally connected with the rivet ring body.

[0011] The multiple partition grooves are evenly spaced along the circumference of the rivet ring, so that multiple elastic clamping pieces form a circumferentially uniform clamping structure around the optical fiber.

[0012] Preferably, the wedge-tightening structure includes a wedge-tightening surface and a wedge-tightening cavity, and the outer wall of the elastic clamping piece is provided with a wedge-tightening surface, which extends obliquely along the axial direction of the rivet ring;

[0013] The inner wall of the tail sleeve is provided with a wedge-tightening cavity. The wedge-tightening cavity has a gradually changing inner wall structure that matches the wedge-tightening surface. As the rivet ring moves axially relative to the tail sleeve, the wedge-tightening surface gradually enters the contraction area of ​​the wedge-tightening cavity, so as to force the elastic clamping piece to deflect towards the central axis of the rivet ring.

[0014] Preferably, the inner side of the elastic clamping piece is provided with a multi-level clamping structure, which includes a rear anti-retraction rib, a middle main load-bearing rib, and a front positioning rib. The rear anti-retraction rib, the middle main load-bearing rib, and the front positioning rib are distributed sequentially along the axial direction of the rivet ring. The rear anti-retraction rib, the middle main load-bearing rib, and the front positioning rib protrude from the inner surface of the elastic clamping piece toward the central axis of the rivet ring.

[0015] Preferably, the front positioning rib is located on the side of the elastic clamping piece close to the front sleeve. The front positioning rib has an arc-shaped rib structure extending circumferentially along the elastic clamping piece. The radial protrusion height of the front positioning rib is less than the radial protrusion height of the central main load-bearing rib. The cross-section of the front positioning rib is a circular arc bulge with a gentle transition on both sides. The front positioning rib is used to perform preliminary positioning and centered clamping of the outer protective layer of the optical fiber when the rivet ring is subjected to wedge tightening.

[0016] The central main load-bearing rib is located in the middle of the elastic clamping piece and extends circumferentially. There are two central main load-bearing ribs along the axial direction of the rivet ring. The protrusion height of the central main load-bearing rib is greater than that of the front positioning rib. The cross-section of the central main load-bearing rib is trapezoidal so as to form multiple axially distributed main clamping areas for the outer protective layer of the optical fiber when the elastic clamping piece contracts radially.

[0017] The rear anti-reverse rib is located on the side of the elastic clamping piece near the tail sleeve. The rear anti-reverse rib is a ring extending in the circumferential direction. The cross-section of the rear anti-reverse rib is an asymmetrical structure with a gentle slope on the front and a steep surface on the rear, so that when the outer protective layer of the optical fiber is subjected to axial tension in the direction of the tail sleeve, it is stopped by the rear anti-reverse rib and the tendency to slide axially relative to the rivet ring is reduced.

[0018] Preferably, each elastic clamping piece has a hook on the outer wall corresponding to the rear of the wedge-tightening surface, and multiple hooks are evenly distributed along the circumference of the rivet ring.

[0019] The hook extends rearward along the axial direction of the elastic clamping piece, and the end of the hook has a hook-shaped structure that protrudes radially outward.

[0020] Preferably, the tail sleeve is a cylindrical structure coaxially arranged with the rivet ring, and an inwardly recessed annular locking groove is provided on the inner wall of the front end cavity of the tail sleeve facing the elastic clamping piece. The shape of the annular locking groove is adapted to the hook.

[0021] When the tail sleeve moves to the designed locking position, each hook synchronously springs radially into the annular locking groove, forming an axial reverse locking structure.

[0022] Preferably, the inner wall of the tail sleeve is provided with a plurality of raised ribs evenly arranged along the axial direction of the tail sleeve. The cross-section of the raised ribs is semi-circular, and the inner diameter of the raised ribs is smaller than the outer diameter of the outer protective layer of the optical fiber, so that the two form an interference fit.

[0023] Multiple axially spaced buffer cavities are formed between two adjacent convex ridges. When the optical fiber is subjected to axial tension, the multiple convex ridges generate frictional resistance with the outer protective layer of the optical fiber in sequence, so as to consume the axial tension in segments and reduce the instantaneous tension peak value transmitted from the tail sleeve to the rivet ring.

[0024] Compared with the prior art, the present invention provides a high tensile strength mechanical locking structure fiber optic patch cord pigtail, which has the following beneficial effects:

[0025] This high-tensile-strength mechanical locking structure for fiber optic patch cords differs from traditional structures that rely primarily on single riveting or friction clamping for tensile fixation. This device utilizes multiple elastic clamping plates on the riveting ring that engage with the wedge-shaped cavity within the tail sleeve. This allows the elastic clamping plates to simultaneously contract radially during axial locking. Furthermore, a multi-level, zoned clamping force structure is formed by the front positioning rib, two central main load-bearing ribs, and the rear anti-reverse rib. Combined with hooks and annular locking grooves for reverse locking, the axial tensile force of the fiber is distributed across multiple clamping areas, reducing stress concentration at a single clamping position. Additionally, the multiple protrusions within the tail sleeve gradually dissipate tensile force through friction, resulting in higher overall tensile strength and locking stability. This effectively reduces the risk of fiber optic protective layer slippage, detachment, and connection failure. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the optical fiber pigtail structure of the present invention;

[0027] Figure 2 This is a cross-sectional view of the present invention;

[0028] Figure 3 This is a schematic diagram of the rear anti-retraction rib structure of the present invention;

[0029] Figure 4 This is a schematic cross-sectional view of the rear anti-retraction rib of the present invention;

[0030] Figure 5 for Figure 2A magnified view of part A in the diagram;

[0031] Figure 6 for Figure 2 A magnified view of section B in the diagram;

[0032] Figure 7 for Figure 2 A magnified view of part C in the diagram;

[0033] Figure 8 This is a schematic diagram of the fiber optic patch cord and pigtail structure of the present invention.

[0034] In the diagram: 1. Tail sleeve; 2. Riveting ring; 3. Elastic clamping plate; 4. Wedge tightening surface; 5. Rear anti-reverse rib; 6. Central main load-bearing rib; 7. Front positioning rib; 8. Rear sleeve; 9. Spring; 10. Ceramic ferrule; 11. Outer nut; 12. Front sleeve; 13. Raised ridge; 14. Wedge tightening cavity; 15. Dividing groove; 16. Annular locking groove; 17. Hook; 18. Optical fiber. Detailed Implementation

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

[0036] Please see Figure 1-8A high tensile strength mechanical locking structure fiber optic patch cord pigtail includes an end connector and an optical fiber 18, consisting of a tail sleeve 1, a rivet ring 2, a rear sleeve 8, a spring 9, a ceramic ferrule 10, an outer nut 11, and a front sleeve 12. The front sleeve 12 has a cylindrical structure, with an internal space for installing the ceramic ferrule 10. The ceramic ferrule 10 is fixedly installed inside the front sleeve 12. An outer nut 11 is fitted on the outer side of the front sleeve 12. The outer nut 11 is used to connect with an external optical fiber adapter interface and can rotate relative to the front sleeve 12 to facilitate the assembly and disassembly of the pigtail with external connection equipment. A rear sleeve 8 is provided behind the ceramic ferrule 10. The rear sleeve 8 and the front sleeve 12 are connected by threads to form a stable axial assembly structure, ensuring a reliable assembly relationship between the front sleeve 12, the rear sleeve 8, and the ceramic ferrule 10. A spring 9 is installed between the ceramic ferrule 10 and the rear sleeve 8. The spring 9 generates an axial elastic preload in the assembled state, thereby providing continuous axial support and elastic compensation for the ceramic ferrule 10. This ensures that the ceramic ferrule 10 maintains a relatively stable contact state when docking with the external connection end and compensates for axial gaps generated during assembly. The ceramic ferrule 10 is fixedly connected to the optical fiber 18, enabling the optical fiber 18 to complete the optical path docking with external optical communication devices through the ceramic ferrule 10. A rivet ring 2 is connected behind the rear sleeve 8. The rivet ring 2 and the tail sleeve 1 together constitute the mechanical locking and protection structure of the tail of the optical fiber 18. The tail sleeve 1 is fitted outside the outer protective layer of the optical fiber 18, forming a protective covering for the connection area of ​​the optical fiber 18 to reduce the adverse effects of external collisions, bending, vibration, and impurities on the internal connection structure. A mechanical locking assembly is provided between the tail sleeve 1 and the rear sleeve 8. The mechanical locking assembly includes an elastic clamping structure and a wedge clamping structure. The elastic clamping structure is set on the rivet ring 2. The wedge clamping structure and the elastic clamping structure cooperate with each other to achieve mechanical clamping and axial locking of the outer protective layer of the optical fiber 18.

[0037] Furthermore, the rivet ring 2 is a stepped cylindrical annular structure coaxially arranged with the optical fiber 18, forming a channel for the optical fiber 18 to pass through. The rear end of the rivet ring 2 forms a continuous annular segment to maintain the overall structural integrity and circumferential stiffness of the rivet ring 2 and provide a stable connection basis for the elastic clamping structure. The front end of the rivet ring 2 forms an elastic clamping structure for clamping the outer protective layer of the optical fiber 18. The elastic clamping structure includes elastic clamping pieces 3 and separating grooves 15. Multiple elastic clamping pieces 3 are distributed circumferentially along the rivet ring 2, and adjacent elastic clamping pieces 3 are separated from each other by the separating grooves 15, so that each elastic clamping piece 3 can generate radial elastic deformation in an independent state. With this structure, the elastic clamping pieces 3 can generate a certain degree of adaptive deflection according to the actual outer peripheral state of the outer protective layer of the optical fiber 18, so that the clamping structure can more fully fit the outer peripheral surface of the optical fiber 18. At the same time, when inserting or removing the optical fiber 18, each elastic clamping piece 3 can provide a certain elastic clearance capacity, thereby facilitating the assembly and maintenance of the pigtail. Multiple elastic clamping plates 3 are evenly distributed along the circumference, which can also make the optical fiber 18 receive a more balanced clamping effect in the circumference, reducing the force deviation of the clamping structure.

[0038] Furthermore, the elastic clamping piece 3 is formed by partially cutting the ring wall of the rivet ring 2, that is, the elastic clamping piece 3 and the rivet ring 2 are an integral structure, which can reduce the setting of independent clamping parts and avoid the problems of complex assembly and clamping position displacement caused by the increase in the number of parts. Each elastic clamping piece 3 is an arc-shaped sheet structure extending along the axial direction of the rivet ring 2. Its inner surface is an arc surface coaxial with the rivet ring 2 and faces the outer protective layer of the optical fiber 18, and its outer surface faces the inner wall of the tail sleeve 1. The arc-shaped sheet structure allows the elastic clamping piece 3 to form a larger circumferential contact coverage area after radial deflection, thereby more fully fitting the outer protective layer of the optical fiber 18; at the same time, the outer surface of the elastic clamping piece 3 can provide structural support for the wedge surface 4, so that when the wedge surface 4 is constrained by the tail sleeve 1, it can transfer the external force to the elastic clamping piece 3, thereby causing the elastic clamping piece 3 to produce stable radial deformation.

[0039] Furthermore, the partition groove 15 extends axially along the rivet ring 2, with its front end penetrating the corresponding end of the rivet ring 2 and its rear end not penetrating the corresponding end of the rivet ring 2, so that the elastic clamping piece 3 remains integrally connected to the body of the rivet ring 2. The partition groove 15 not only separates adjacent elastic clamping pieces 3, giving each elastic clamping piece 3 independent elastic deformation space, but also reduces the linkage interference between adjacent elastic clamping pieces 3. This prevents excessive synchronous deformation of adjacent elastic clamping pieces 3 when one elastic clamping piece 3 undergoes radial deflection, thereby improving the independent adaptability of each elastic clamping piece 3. The cavity formed by the partition groove 15 also provides clearance space for the radial inward deflection of the elastic clamping piece 3, allowing it to smoothly undergo elastic deformation when subjected to wedging action. Since the rear end of the partition groove 15 does not penetrate the rivet ring 2, the rear side of the rivet ring 2 maintains a continuous structure, which is beneficial to maintaining the overall deformation resistance and axial load-bearing capacity of the rivet ring 2, so that the elastic deformation of the elastic clamping piece 3 is mainly concentrated in its own area. Multiple partition grooves 15 are evenly distributed around the circumference of the rivet ring 2, so that multiple elastic clamping pieces 3 form a circumferentially uniform clamping structure around the optical fiber 18.

[0040] Furthermore, the wedge-tightening structure includes a wedge-tightening surface 4 and a wedge-tightening cavity 14. The outer wall of the elastic clamping piece 3 is provided with a wedge-tightening surface 4, which extends obliquely along the axial direction of the rivet ring 2; the inner wall of the tail sleeve 1 is correspondingly provided with a wedge-tightening cavity 14, which forms a gradient inner wall structure that matches the wedge-tightening surface 4. When there is axial relative movement between the rivet ring 2 and the tail sleeve 1, the wedge-tightening surface 4 can gradually form an abutment fit with the gradient inner wall of the wedge-tightening cavity 14, and gradually enter the contraction area of ​​the wedge-tightening cavity 14 with the relative movement, so that the inner wall of the tail sleeve 1 forms a continuous radial constraint on the outer side of the elastic clamping piece 3. This wedge-tightening structure can transform the axial assembly action between the tail sleeve 1 and the rivet ring 2 into the radial clamping action of the elastic clamping piece 3, thus completing the mechanical locking of the optical fiber 18 without the need for an additional radial drive structure. At the same time, the cooperation between the wedge-tightening surface 4 and the wedge-tightening cavity 14 can form a stable constraint on the outer side of the elastic clamping piece 3, making it less likely for the elastic clamping piece 3 to swing disorderly under external vibration or impact, thereby improving the stability of the overall mechanical locking structure.

[0041] Furthermore, the inner side of the elastic clamping piece 3 is provided with a multi-level clamping structure, which includes a rear anti-retraction rib 5, a central main load-bearing rib 6, and a front positioning rib 7. The rear anti-retraction rib 5, the central main load-bearing rib 6, and the front positioning rib 7 are distributed sequentially along the axial direction of the rivet ring 2, and protrude from the inner surface of the elastic clamping piece 3 towards the central axis of the rivet ring 2. By forming multiple clamping areas with different functions on the same elastic clamping piece 3, the elastic clamping structure can take into account the positioning, load-bearing, and anti-retraction functions of the optical fiber 18, avoiding the concentration of all clamping loads on a single position. At the same time, each clamping rib and the elastic clamping piece 3 adopt an integrated mating structure, which can improve the overall structural integrity of the clamping area and reduce the possibility of loosening or displacement of independent clamping parts during long-term use.

[0042] Furthermore, the front positioning rib 7 is located on the side of the elastic clamping piece 3 near the front sleeve 12, and is an arc-shaped rib structure extending circumferentially along the elastic clamping piece 3. Its radial protrusion height is less than that of the central main load-bearing rib 6, and its cross-section is a rounded arc shape, forming a relatively gentle transition structure on both sides. When clamping the optical fiber 18, the front positioning rib 7 can not only perform preliminary positioning and centering of the outer protective layer of the optical fiber 18, but also guide the optical fiber 18 when it enters the clamping area or is subjected to slight radial disturbance, so that the optical fiber 18 can maintain a coaxial state with the rivet ring 2 as much as possible, thus establishing a more reasonable force foundation for the subsequent main load-bearing area. The central main load-bearing rib 6 is located in the middle of the elastic clamping piece 3 and extends circumferentially. Two ribs are spaced apart along the axial direction of the rivet ring 2. The radial protrusion height of the central main load-bearing rib 6 is greater than that of the front positioning rib 7. Its cross-section is trapezoidal, which allows the central main load-bearing rib 6 to form a relatively stable contact area with the outer protective layer of the optical fiber 18 after the elastic clamping piece 3 radially contracts. The two central main load-bearing ribs 6 together form multiple axially distributed main load-bearing positions, which helps to distribute the external axial load to different positions. The rear anti-reverse rib 5 is located on the side of the elastic clamping piece 3 near the tail sleeve 1. It is an arc-shaped rib structure extending circumferentially along the elastic clamping piece 3. Its cross-section adopts an asymmetrical structure with a gentle slope on the front and a steep surface on the rear. When the optical fiber 18 is assembled, the gentle slope on the front can provide a smoother introduction transition and reduce the jamming during the insertion of the optical fiber 18. When the optical fiber 18 has an axial movement tendency toward the tail sleeve 1, the steeper stop surface on the rear can form a significant axial block with the outer protective layer of the optical fiber 18, thereby reducing the axial slippage tendency of the optical fiber 18 relative to the rivet ring 2.

[0043] Furthermore, each elastic clamping piece 3 has a hook 17 positioned behind the wedge-tightening surface 4 on its outer wall, with multiple hooks 17 evenly distributed circumferentially along the rivet ring 2. The hooks 17 extend rearward along the axial direction of the elastic clamping piece 3, with their ends forming radially outward-protruding hook-like structures. The hooks 17 are connected to the elastic clamping piece 3, allowing them to undergo a certain radial displacement according to the elastic state of the elastic clamping piece 3. This enables them to elastically yield during the assembly of the tail sleeve 1 and return to the locked state after reaching the locking position. The even circumferential arrangement of multiple hooks 17 ensures a relatively balanced circumferential locking relationship between the tail sleeve 1 and the rivet ring 2, preventing force imbalance caused by unilateral locking. The hook-like ends of the hooks 17 form a clear stop structure to limit the relative axial movement between the tail sleeve 1 and the rivet ring 2.

[0044] Furthermore, the tail sleeve 1 is a cylindrical structure coaxially arranged with the rivet ring 2. An inwardly recessed annular locking groove 16 is formed on the inner wall of its front end, matching the hook-shaped end of the hook 17. When the tail sleeve 1 and rivet ring 2 move to the designed locking position, each hook 17 can synchronously and radially enter the annular locking groove 16 under its own elastic restoring force, thus forming an axially reversed locking structure between the tail sleeve 1 and the rivet ring 2. The annular locking groove 16 provides a stable accommodating space for the hook 17, making it difficult for the hook 17 to radially disengage after entering the locking groove. Simultaneously, since the annular locking groove 16 is continuously arranged along the circumference of the tail sleeve 1, even if there is a certain degree of relative circumferential rotation between the tail sleeve 1 and the rivet ring 2, the hook 17 can still remain within the locking groove area, thereby improving the adaptability of the locking structure. After the hook 17 and the annular locking groove 16 are engaged, the relative axial position of the tail sleeve 1 and the rivet ring 2 can be maintained, so that the wedge tightening surface 4 and the wedge tightening cavity 14 maintain a stable fit, reducing the possibility that the tail sleeve 1 will retract due to vibration or reverse force, resulting in a decrease in clamping force.

[0045] Furthermore, the inner wall of the tail sleeve 1 is provided with multiple raised ribs 13 evenly arranged along the axial direction of the tail sleeve 1. The cross-section of the raised ribs 13 is semi-circular, and its inner diameter is smaller than the outer diameter of the outer protective layer of the optical fiber 18, so that the raised ribs 13 and the outer protective layer of the optical fiber 18 form an interference contact. The multiple raised ribs 13 form a segmented contact interface along the axial direction, which can not only generate frictional resistance, but also provide multi-point support for the outer protective layer of the optical fiber 18, so as to limit the significant radial sway of the optical fiber 18 inside the tail sleeve 1. The semi-circular cross-section of the raised ribs 13 can reduce the local compression of the outer protective layer of the optical fiber 18 caused by sharp edges, making it more suitable for working environments that are subject to long-term vibration and bending. Multiple axially spaced buffer cavities are formed between two adjacent raised ribs 13, which can provide a certain clearance space for the local elastic deformation of the outer protective layer of the optical fiber 18, so that the tail sleeve 1 can maintain a certain degree of flexibility when subjected to external bending or vibration, while enhancing the tightness of the connection between the tail sleeve 1 and the optical fiber 18, and reducing the loosening of the optical fiber 18 inside the tail sleeve 1.

[0046] Working Principle: During operation, the optical fiber 18 is first inserted into the tail sleeve 1, the rivet ring 2, and the rear sleeve 8, and the outer protective layer of the optical fiber 18 enters the clamping channel formed by multiple elastic clamping pieces 3. During overall assembly, the front sleeve 12 and the rear sleeve 8 are gradually locked together by a threaded connection, and the ceramic ferrule 10 remains fixedly connected to the optical fiber 18. The spring 9 located between the ceramic ferrule 10 and the rear sleeve 8 is axially compressed during assembly, thereby continuously generating an elastic preload towards the ceramic ferrule 10. This ensures that the ceramic ferrule 10 maintains a stable end-face fit when connected to an external adapter, reducing the problem of insufficient optical end-face contact caused by vibration or slight displacement during the connection process. The outer nut 11 can connect and fix the pigtail to the external device by cooperating with the external connector adapter structure. After the basic assembly is completed, the mechanical locking assembly begins to perform high tensile locking on the outer protective layer of the optical fiber 18.

[0047] When the rivet ring 2 and the tail sleeve 1 move relative to each other in a predetermined axial direction, the wedge-tightening surface 4 located on the outside of the elastic clamping piece 3 gradually comes into contact with the wedge-tightening cavity 14 inside the tail sleeve 1. As the wedge-tightening surface 4 continuously enters the contraction area of ​​the wedge-tightening cavity 14, the radial constraint it receives gradually increases. Since the multiple elastic clamping pieces 3 are separated from each other by the partition groove 15, and the rear end of the elastic clamping piece 3 is still integrally connected to the body of the rivet ring 2, each elastic clamping piece 3 can generate independent radial inward deflection with its connection part as the elastic fulcrum. Under the wedge-tightening action, the multiple elastic clamping pieces 3 simultaneously contract towards the central axis of the rivet ring 2, thereby gradually reducing the clamping channel with a certain gap and applying radial clamping force to the outer protective layer of the optical fiber 18.

[0048] Because multiple elastic clamping plates 3 are evenly distributed circumferentially, the resulting clamping force can achieve a relatively uniform circumferential covering force around the optical fiber 18. Compared with the fixing method that relies on single-point pressing, it can reduce excessive local pressure and damage to the protective layer caused by force eccentricity, while improving the overall friction bearing capacity between the optical fiber 18 and the rivet ring 2. During the continuous radial contraction of the elastic clamping plates 3, the front positioning rib 7 set on its inner side first makes contact with the outer protective layer of the optical fiber 18. Utilizing its small radial protrusion height and arc-shaped cross-section, it can guide, center, and initially position the optical fiber 18 in the initial clamping stage, avoiding large swaying of the optical fiber 18 during the force process, so that each subsequent force-bearing area can maintain a relatively reasonable force state.

[0049] As the wedge-tightening surface 4 further enters the contraction region of the wedge-tightening cavity 14, the central main load-bearing ribs 6, due to their large radial protrusion height and the presence of two axially spaced ribs, can simultaneously compress the outer protective layer of the optical fiber 18, forming multiple axially spaced main load-bearing areas. When the optical fiber 18 is subjected to axial tension, a large frictional resistance is generated between each central main load-bearing rib 6 and the protective layer, causing the external tension to no longer be concentrated at a single location, but rather distributed and transmitted among multiple clamping areas, thereby effectively reducing the load borne by a unit clamping area.

[0050] Meanwhile, the rear anti-reverse rib 5 utilizes an asymmetrical cross-sectional structure with a gentle slope on the front and a steep surface on the rear. During normal assembly, this facilitates the entry of the optical fiber 18 into the clamping area. When the optical fiber 18 is subjected to axial tension towards the tail sleeve 1, the protective layer is stopped by the relatively steep rear side of the rear anti-reverse rib 5. This makes it increasingly difficult for the optical fiber 18 to slide outward under external tension, thus creating a significant axial anti-reverse effect. Therefore, the front positioning rib 7, the central main load-bearing rib 6, and the rear anti-reverse rib 5 form a multi-level clamping relationship that gradually connects positioning, main load-bearing, and anti-reverse, allowing the axial load on the optical fiber 18 to be transmitted and dissipated along multiple contact areas, avoiding the traditional single adhesive interface directly bearing all the tension.

[0051] Meanwhile, after the tail sleeve 1 and the rivet ring 2 reach the designed locking position, the hooks 17 located on the outside of each elastic clamping piece 3 enter the corresponding area of ​​the annular locking groove 16 as the tail sleeve 1 moves relative to it. When the hooks 17 pass the limiting part of the annular locking groove 16, they spring radially outward into the annular locking groove 16 under their own elastic recovery, thus forming a reverse locking position between the tail sleeve 1 and the rivet ring 2. At this time, even if the external structure is subjected to an axial force that causes the tail sleeve 1 to retract in the opposite direction, the hooks 17 will be blocked by the annular locking groove 16, making it difficult for the established wedge-tight state to be released on its own. Therefore, the mechanical locking state can be maintained for a second time, reducing the risk of decreased clamping force caused by long-term vibration, repeated pulling, and axial retraction of the tail sleeve 1 during equipment movement.

[0052] Based on this, the multiple protrusions 13 on the inner wall of the tail sleeve 1 can also form an interference contact with the outer protective layer of the optical fiber 18. When the optical fiber 18 is subjected to external axial tension, a large frictional resistance will first be generated at the protrusions 13. Since each protrusion 13 is continuously distributed along the axial direction, it can segmentally bear and gradually consume the tension. The buffer cavity formed between adjacent protrusions 13 provides a certain deformation release space for the outer protective layer of the optical fiber 18, so that when the optical fiber 18 is subjected to instantaneous impact load, it will not concentrate all the load to the mechanical clamping area of ​​the rivet ring 2. Instead, it will first be dispersed and attenuated by the friction between the multiple protrusions 13 and the protective layer, so that the instantaneous tension peak transmitted to the rear mechanical locking area is reduced, thereby further reducing the instantaneous load on the elastic clamping piece 3, the central main load-bearing protrusion 6 and the rear anti-reverse protrusion 5.

[0053] When the external tension continues to increase, the multiple protruding ribs 13 inside the tail sleeve 1 and the multi-level clamping structure on the rivet ring 2 work together to transmit the axial load step by step along the path of "tail sleeve friction buffer, elastic clamping tightening, multi-level rib bearing, and rear side anti-reverse limit". This avoids the tension being directly concentrated at the fixed connection between the ceramic ferrule 10 and the optical fiber 18, thereby reducing the risk of peeling, loosening, and fiber detachment caused by overload of the connecting adhesive layer or the end of the optical fiber 18.

[0054] During long-term use, even under repeated deformation caused by cabinet vibration, equipment weight pulling, construction dragging, and changes in ambient temperature, the hook 17 and the annular locking groove 16 can still maintain the relative locking of the tail sleeve 1 and the rivet ring 2. The wedge-tightening surface 4 and the wedge-tightening cavity 14 continuously maintain the radial constraint of the elastic clamping piece 3. The multi-level clamping ribs continue to implement multi-area limiting on the outer protective layer of the optical fiber 18, thus forming a continuous and stable tensile holding force at the mechanical structure level. The end pre-tightening effect provided by the spring 9 and the stable connection formed by the outer nut 11 and the external connection interface can ensure that the ceramic ferrule 10 maintains good axial contact stability during equipment docking, so that the mechanical fixation reliability and optical connection stability complement each other.

[0055] Therefore, the entire device does not rely on a single adhesive bonding interface to bear external loads. Instead, it forms a continuous mechanical tensile force system through the mechanical pressure of the elastic clamping piece 3 and the wedge-tightening cavity 14, the multi-level distributed clamping of the front positioning rib 7, the middle main load-bearing rib 6 and the rear anti-retraction rib 5, the reverse locking of the hook 17 and the annular locking groove 16, and the friction buffering of multiple protruding ribs 13. This allows the external axial tensile force to be dispersed, limited and gradually attenuated, thereby effectively improving the tensile load-bearing capacity, locking stability and long-term reliability of the fiber optic patch cord pigtail, and reducing optical path loss fluctuations, signal instability or even communication interruption caused by axial slippage of the fiber 18, loose connection or end fiber detachment.

[0056] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high tensile strength mechanical locking structure fiber optic patch cord pigtail, characterized in that, include: An end connector and an optical fiber (18) are composed of a tail sleeve (1), a rivet ring (2), a rear sleeve (8), a spring (9), a ceramic ferrule (10), an outer nut (11), and a front sleeve (12). The ceramic ferrule (10) is installed inside the front sleeve (12). The outer nut (11) is fitted on the outside of the front sleeve (12), and the outer nut (11) and the front sleeve (12) are movably connected. The rear sleeve (8) is installed behind the ceramic ferrule (10), and the rear sleeve (8) and the front sleeve (12) are threaded together. A spring (9) is installed between the ceramic ferrule (10) and the rear sleeve (8). The rivet ring (2) is installed behind the rear sleeve (8), and the tail sleeve (1) is installed behind the rivet ring (2). The optical fiber (18) is fixedly installed on the ceramic ferrule (10), and the tail sleeve (1) is fitted on the outside of the outer protective layer of the optical fiber (18). A mechanical locking assembly is provided between the tail sleeve (1) and the rear sleeve (8). The mechanical locking assembly includes an elastic clamping structure and a wedge clamping structure. The elastic clamping structure is provided on the rivet ring (2), and the wedge clamping structure and the elastic clamping structure cooperate with each other.

2. The high-tensile mechanical spliceable fiber optic cable jumper of claim 1, wherein, The rivet ring (2) is a stepped cylindrical ring structure coaxial with the optical fiber (18). The rear end of the rivet ring (2) forms a continuous ring segment, and the front end of the rivet ring (2) forms an elastic clamping structure for clamping the outer protective layer of the optical fiber (18). The elastic clamping structure includes elastic clamping pieces (3) and partition grooves (15). Multiple elastic clamping pieces (3) are arranged at intervals along the circumference of the rivet ring (2). Adjacent elastic clamping pieces (3) are separated from each other by partition grooves (15), so that each elastic clamping piece (3) can generate independent radial elastic deflection relative to the main body of the rivet ring (2).

3. The high-tensile mechanical spliceable fiber optic cable jumper of claim 2, wherein, The elastic clamping piece (3) is formed by partially cutting the ring wall of the rivet ring (2). Each elastic clamping piece (3) is an arc-shaped sheet structure extending along the axial direction of the rivet ring (2). The inner side of the elastic clamping piece (3) is an arc surface coaxial with the rivet ring (2). The inner side of the elastic clamping piece (3) faces the protective layer outside the optical fiber (18), and the outer side faces the inner wall of the tail sleeve (1).

4. The high-tensile mechanical spliceable fiber optic cable jumper of claim 3, wherein, The partition groove (15) extends along the axial direction of the rivet ring (2). The front end of the partition groove (15) passes through the corresponding end of the rivet ring (2), and the rear end of the partition groove (15) does not pass through the corresponding end of the rivet ring (2), so that the elastic clamping piece (3) remains integrally connected with the rivet ring (2) body. Multiple partition grooves (15) are evenly spaced along the circumference of the rivet ring (2), so that multiple elastic clamping pieces (3) form a circumferentially uniform clamping structure around the optical fiber (18).

5. The high-tensile mechanical spliceable fiber optic cable jumper of claim 2, wherein, The wedge clamping structure includes a wedge clamping surface (4) and a wedge clamping cavity (14). The outer side wall of the elastic clamping piece (3) is provided with a wedge clamping surface (4), which extends obliquely along the axial direction of the rivet ring (2). The inner wall of the tail sleeve (1) is provided with a wedge-tightening cavity (14). The wedge-tightening cavity (14) has a gradually changing inner wall structure that matches the wedge-tightening surface (4). As the rivet ring (2) moves axially relative to the tail sleeve (1), the wedge-tightening surface (4) gradually enters the contraction area of ​​the wedge-tightening cavity (14) to force the elastic clamping piece (3) to deflect towards the central axis of the rivet ring (2).

6. The high tensile strength mechanical locking structure fiber optic patch cord pigtail according to claim 3, characterized in that, The inner side of the elastic clamping piece (3) is provided with a multi-level clamping structure, which includes a rear anti-retraction rib (5), a middle main load-bearing rib (6) and a front positioning rib (7). The rear anti-retraction rib (5), the middle main load-bearing rib (6) and the front positioning rib (7) are distributed sequentially along the axial direction of the rivet ring (2). The rear anti-retraction rib (5), the middle main load-bearing rib (6) and the front positioning rib (7) protrude from the inner surface of the elastic clamping piece (3) toward the central axis of the rivet ring (2).

7. The high tensile strength mechanically locked fiber optic patch cord pigtail according to claim 6, characterized in that, The front positioning rib (7) is located on the side of the elastic clamping piece (3) close to the front sleeve (12). The front positioning rib (7) is an arc-shaped rib structure extending circumferentially along the elastic clamping piece (3). The radial protrusion height of the front positioning rib (7) is less than the radial protrusion height of the central main bearing rib (6). The cross-section of the front positioning rib (7) is a circular arc bulge with a gentle transition on both sides. The front positioning rib (7) is used to perform preliminary positioning and centered clamping of the outer protective layer of the optical fiber (18) when the rivet ring (2) is wedge-tightened. The central main load-bearing rib (6) is located in the middle of the elastic clamping piece (3) and extends circumferentially. There are two central main load-bearing ribs (6) along the axial direction of the rivet ring (2). The protrusion height of the central main load-bearing rib (6) is greater than that of the front positioning rib (7). The cross-section of the central main load-bearing rib (6) is trapezoidal so as to form multiple axially distributed main clamping areas for the outer protective layer of the optical fiber (18) when the elastic clamping piece (3) contracts radially. The rear anti-reverse rib (5) is located on the side of the elastic clamping piece (3) near the tail sleeve (1). The rear anti-reverse rib (5) is a ring extending in the circumferential direction. The cross-section of the rear anti-reverse rib (5) is an asymmetrical structure with a gentle slope on the front and a steep surface on the rear, so that when the outer protective layer of the optical fiber (18) is subjected to axial tension in the direction of the tail sleeve (1), it is stopped by the rear anti-reverse rib (5) and the axial slippage tendency relative to the rivet ring (2) is reduced.

8. The high tensile strength mechanical locking structure fiber optic patch cord pigtail according to claim 5, characterized in that, Each elastic clamping piece (3) has a hook (17) on the outer wall corresponding to the rear of the wedge-tightening surface (4), and multiple hooks (17) are evenly distributed along the circumference of the rivet ring (2); The hook (17) extends rearward along the axial direction of the elastic clamping piece (3), and the end of the hook (17) has a hook-shaped structure that protrudes radially outward.

9. The high tensile strength mechanically locked fiber optic patch cord pigtail according to claim 8, characterized in that, The tail sleeve (1) is a cylindrical structure coaxially arranged with the rivet ring (2). The inner wall of the front end cavity of the tail sleeve (1) facing the elastic clamping piece (3) is provided with an inwardly recessed annular locking groove (16). The shape of the annular locking groove (16) is adapted to the hook (17). When the tail sleeve (1) moves to the designed locking position, each hook (17) synchronously springs radially into the annular locking groove (16) to form an axial reverse locking structure.

10. A high tensile strength mechanically locked fiber optic patch cord pigtail according to claim 1, characterized in that, The inner wall of the tail sleeve (1) is provided with a number of protruding ribs (13) evenly arranged along the axial direction of the tail sleeve (1). The cross section of the protruding ribs (13) is semi-circular. The inner diameter of the protruding ribs (13) is smaller than the outer diameter of the outer protective layer of the optical fiber (18). The two form an interference fit. Multiple buffer cavities are formed between two adjacent convex ridges (13). When the optical fiber (18) is subjected to axial tension, the multiple convex ridges (13) generate frictional resistance with the outer protective layer of the optical fiber (18) in sequence, so as to consume the axial tension in segments and reduce the instantaneous tension peak value transmitted from the tail sleeve (1) to the rivet ring (2).

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