CN-121978806-A - Four-core beam-expanding type oil-filled optical fiber connector and assembly method thereof

CN121978806ACN 121978806 ACN121978806 ACN 121978806ACN-121978806-A

Abstract

The invention discloses a connector technology, and aims to provide a four-core beam expansion type oil-filled optical fiber connector and an assembly method thereof, wherein the technical scheme is characterized by comprising a screw sleeve, a plug shell, four optical fiber beam expansion insulators, a pressure compensator, an oil-filled plug tail clamp, a sealing assembly and a calibration gasket which is clamped between the oil-filled plug tail clamp and a butt joint end surface of the plug shell and is used for adjusting the precompression stroke of the pressure compensator; the screw sleeve, the plug shell, the four optical fiber beam expansion insulators, the pressure compensator, the oil filling plug tail clamp, the sealing assembly and the calibration gasket are enclosed together to form a completely closed oil filling cavity, and the degassed fluorinated oil or synthetic hydrocarbon oil is injected into the oil filling cavity through a valve and matched with the pressure compensator to construct an active pressure compensation sealing system. The invention is suitable for the technical field of connectors.

Inventors

CHEN YI
ZHANG BO
XU XIAODONG

Assignees

上海蓝梭电子科技有限公司
浙江蓝梭海洋科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260317

Claims (6)

1. The four-core beam expansion type oil-filled optical fiber connector is characterized by comprising a screw sleeve (1), a plug shell (2), four optical fiber beam expansion insulators (3), a pressure compensator (4), an oil-filled plug tail clamp (5), a sealing assembly and a calibration gasket which is clamped between the butt joint end surfaces of the oil-filled plug tail clamp (5) and the plug shell (2) and is used for adjusting the precompression stroke of the pressure compensator (4); an insulator cavity (6) for accommodating the four optical fiber expanding insulators (3) and a compensation cavity (7) for accommodating the pressure compensator (4) are arranged in the plug shell (2); the screw sleeve (1) is arranged at the front end of the plug housing (2) through a thread connecting sleeve and is used for coaxially fixing the four optical fiber expanded beam insulators (3) in the plug housing (2) and providing initial mechanical pretightening force; The four-fiber beam expansion insulator (3) is arranged in the insulator cavity (6), is integrated with four independent optical beam expansion channels and is used for realizing signal beam expansion transmission of a four-core optical fiber unit, an integrally formed anti-rotation key is arranged on the outer wall of the four-fiber beam expansion insulator (3), and the anti-rotation key is matched with a key groove on the inner wall of the plug shell (2); The pressure compensator (4) is arranged in an inner compensation cavity (7) of the plug shell (2), a uniform annular gap is formed between the outer wall of the inner compensation cavity (7) and the inner wall of the inner compensation cavity, and the outer surface of the pressure compensator (4) is coated with compatible silicone grease with the thickness of 0.02-0.05 mm; the oil-filled plug tail clamp (5) is connected with the rear end of the plug shell (2) through threads, the front end of the oil-filled plug tail clamp is used for axially limiting and initially pre-compressing the pressure compensator (4), and a valve for vacuum extraction, oil filling and final sealing functions is arranged on the side wall of the oil-filled plug tail clamp (5); the sealing assembly comprises a polyurethane buffer protection tube sleeved on the four-core optical fiber unit and sleeved on the tail pipe part of the oil-filled plug tail clamp (5), and a stainless steel double-steel-wire reinforced hose clamp for radially and uniformly compacting and fixing the overlapping area of the polyurethane buffer protection tube and the tail pipe part to form a strain release and anti-kink barrier; The plug screw comprises a screw sleeve (1), a plug shell (2), four optical fiber beam expansion insulators (3), a pressure compensator (4), an oil filling plug tail clamp (5), a sealing assembly and a calibration gasket, wherein the screw sleeve, the plug shell, the four optical fiber beam expansion insulators, the oil filling plug tail clamp, the sealing assembly and the calibration gasket jointly enclose to form a completely-closed oil filling cavity, and the oil filling cavity is filled with degassed fluorinated oil or synthesized hydrocarbon oil through a valve and matched with the pressure compensator (4) to construct an active pressure compensation sealing system.
2. The four-core expanded beam type oil-filled optical fiber connector according to claim 1, wherein the ratio of the precompression stroke of the pressure compensator (4) to the effective axial length of the compensating cavity (7) inside the plug housing (2) is 1:12-1:8, and the initial micro-positive pressure of the oil-filled cavity in the ratio interval at normal pressure can be stably maintained at 0.5-1bar for forming a self-sealing mechanism of oil active extravasation.
3. The four-core expanded beam type oil-filled optical fiber connector according to claim 1, wherein the pressure compensator (4) is of a stainless steel bellows type elastic structure, the ratio of the effective expansion amount to the free length of the bellows is 1:3-1:5, and the ratio of the elastic coefficient of the bellows to the volume of the oil-filled cavity is 0.02-0.05MPa/mL, so as to realize rapid dynamic response to environmental pressure change and avoid sealing failure caused by excessive deformation.
4. A method of assembling a four-core expanded beam-filled fiber optic connector as defined in any one of claims 1-3, comprising the steps of: S1, accurately aligning anti-rotation keys of the four optical fiber beam expansion insulators (3) with key grooves on the inner wall of a plug shell (2), slowly pushing the four optical fiber beam expansion insulators (3) into an insulator cavity (6) of the plug shell (2) along the axial direction, completing coaxial initial assembly, detecting the parallelism between an optical end face and a front end standard face of the shell by adopting a parallel light detector, and ensuring that the parallelism deviation is less than or equal to 0.02 degrees; S2, sleeving the screw sleeve (1) at the front end of the plug shell (2), and tightening by adopting a torque wrench according to a three-stage sequence torque, wherein the torque wrench is used for exerting 30% of target torque in the first stage, standing for 5min to eliminate local stress, exerting 60% of target torque in the second stage, standing for 5min again, exerting 100% of target torque in the third stage, and achieving final pretension and accurate axial positioning of the optical end face; S3, uniformly coating a layer of compatible silicone grease with the thickness of 0.02-0.05mm on the outer wall of the pressure compensator (4), slowly pushing the pressure compensator (4) into a compensation cavity (7) of the plug shell (2) along the axial direction, and detecting an annular gap between the outer wall of the pressure compensator (4) and the inner wall of the cavity through a plug gauge to ensure that the gap uniformity deviation is less than or equal to 0.05mm; s4, aligning external threads of the oil-filled plug tail clamp (5) with internal threads at the rear end of the plug shell (2), selecting a calibration gasket with a preset thickness to be placed on a connecting end face, and pre-connecting by adopting a manual screwing mode until the front end of the oil-filled plug tail clamp (5) axially limits the pressure compensator (4) so as to avoid compensator deformation caused by forced screwing; S5, the screw-in depth of the oil filling plug tail clamp (5) is monitored in real time through a high-precision displacement sensor, meanwhile, the axial pre-pressure borne by the pressure compensator (4) is detected through a miniature pressure sensor, and the pressure compensator (4) is compressed to a designed pre-pressure stroke by combining with adjustment gaskets with different thicknesses, so that an initial micro-positive pressure of 0.5-1bar is established for the oil filling cavity under normal pressure; S6, cutting the polyurethane buffer protection tube according to a preset length, sleeving the polyurethane buffer protection tube outside the four-core optical fiber unit to be connected, and inserting the sleeved optical fiber unit and the polyurethane buffer protection tube into a tail tube part of an oil-filled plug tail clamp (5) together until the front end surface of the polyurethane buffer protection tube is completely attached to the inner step surface of the tail tube; S7, sleeving a stainless steel double-steel-wire reinforced hose clamp on the overlapping part of the polyurethane buffer protection tube and the tail tube of the oil-filled plug end clamp (5), tightening the hose clamp according to a specified torque by adopting a torque wrench, so that the hose clamp forms uniform radial compression force on the polyurethane buffer protection tube, and constructing a preliminary optical fiber strain release and anti-torsion barrier; s8, respectively connecting a valve on an oil-filled plug tail clamp (5) to a vacuum system and an oil storage pressurizing system through a pressure-resistant pipeline, starting the vacuum system, pumping the interior of an oil-filled cavity to a high vacuum degree of 1X 10 < -3 > Pa, maintaining the vacuum state for 30min, detecting residual gas components through a mass spectrometer, and thoroughly removing air, moisture and volatile impurities in the cavity; S9, on the premise of maintaining the high vacuum state of the oil filling cavity, closing the vacuum system and switching to an oil storage pressurizing system, slowly injecting low-viscosity high-stability fluorinated oil or synthetic hydrocarbon oil subjected to 72h degassing treatment into the oil filling cavity under the positive pressure of 0.2-0.3MPa until the oil continuously overflows from the valve; s10, closing and sealing the valve, placing the assembled connector in a constant temperature and humidity environment with the temperature of 25 ℃ plus or minus 1 ℃ and the humidity of 50% plusor minus 5%, standing for 24 hours, detecting the pressure change rate of the oil filling cavity and the optical coupling loss of the four channels, confirming that the pressure compensation system and the optical transmission performance meet the design requirements, and completing the construction of the active pressure compensation sealing system.
5. The method of assembling a four-core expanded beam-filled fiber optic connector according to claim 4, wherein the controlling of the pre-compression stroke of the pressure compensator (4) in S5 comprises: S51, firstly, acquiring real-time screwing depth L of an oil-filled plug tail clamp (5) through a displacement sensor, acquiring real-time axial precompression F of a pressure compensator (4) through a miniature pressure sensor, and acquiring current environment temperature T through a temperature sensor; S52, based on a preset elastic characteristic curve of the pressure compensator (4), establishing the relation between a pre-compression stroke L0 and pre-compression force F0 and a temperature T, wherein F0=kX [ L0-alpha X (T-Tc) ], k is the elastic coefficient of the pressure compensator (4), alpha is a temperature-length conversion coefficient, and Tc is a preset standard reference temperature; S53, substituting L, F, T collected in real time, calculating to obtain theoretical precompression fp=k× [ L- α× (T-Tc) ], if the deviation Δf= |f-fp| > of F and Fp is a preset threshold Δfmax, Δfmax=0.02×fp, determining that the current precompression state is abnormal, and executing the following adjustment logic: s54, if delta F is larger than delta Fmax and F is smaller than Fp, the precompression stroke is insufficient, the thickness of the calibration gasket is increased by 0.02mm each time, the oil-filled plug end clamp (5) is screwed in again, and L and F are monitored until delta F is smaller than or equal to delta Fmax; S55, if delta F is larger than delta Fmax and F is larger than Fp, the precompression stroke is overlarge, the thickness of the calibration gasket is reduced by 0.02mm each time, the oil-filled plug end clamp (5) is screwed in again, and L and F are monitored until delta F is smaller than or equal to delta Fmax; S56, if the delta F is less than or equal to delta Fmax, calculating initial micro positive pressure P=F/S based on the effective stress area S of the pressure compensator (4), judging that the precompression setting is completed if the P is in a 0.5-1bar interval, replacing a calibration gasket with the thickness reduced by 0.01mm and screwing again if the P is less than 0.5bar, and replacing the calibration gasket with the thickness increased by 0.01mm and screwing again if the P is more than 1bar until the P is stabilized in the 0.5-1bar interval.
6. The method of assembling a four-core expanded beam type oil-filled fiber optic connector according to claim 4, wherein the controlling the vacuum filling process in S8 and S9 comprises: In the vacuum extraction stage, monitoring the vacuum degree Pr of the oil filling cavity in real time by a vacuum gauge, detecting the residual gas component in the cavity by a mass spectrometer, and judging that the vacuum removal stage is finished if Pr is reduced to 1 x 10 < -3 > Pa and the holding time to is more than or equal to 30min, and the total content ratio of water and volatile organic matters in the residual gas is less than or equal to 0.1%; If Pr is reduced to 1 x 10 < -3 > Pa but to <30min, or the residual gas ratio is more than 0.1%, prolonging the vacuum holding time, and re-detecting the gas components and the vacuum degree every 10min until the conditions are met; in the oil filling stage, monitoring oil filling flow Q through a flow sensor, monitoring pressure Pb in a cavity through a pressure sensor, and monitoring oil liquid level H through a liquid level sensor; Establishing a filling rate of qp=c x v (Pa-Pb), wherein C is a flow coefficient and Pa is an output pressure of the oil storage pressurization system; if the deviation delta Q= |Q-qp| >0.05 xqp and Pa >0.35MPa of the real-time flow Q and the calculated value Qp are judged to be the blockage of the filling pipeline, the filling is stopped, and the filling is restarted after the inert gas is introduced to purge the pipeline for 30 s; if the delta Q is more than 0.05 xQp and the Pa is less than 0.2MPa, judging that the pressure of the oil storage pressurizing system is insufficient, regulating the output pressure of the pressurizing system to 0.25MPa, and continuing pouring after the pressure is stable; when the liquid level H reaches the full liquid level threshold Hmax of the cavity and the valve continuously overflows the oil for more than or equal to 5s, judging that the filling is finished, and closing the valve; if H reaches Hmax and the oil-free liquid of the valve overflows, judging that the valve is blocked, reversely introducing 0.1MPa inert gas to purge the valve until the oil stably overflows, and then completing valve sealing.

Description

Four-core beam-expanding type oil-filled optical fiber connector and assembly method thereof Technical Field The invention relates to a connector technology, in particular to a four-core beam expansion type oil-filled optical fiber connector and an assembling method thereof. Background The system-level water tightness of the traditional beam-expanding type four-fiber connector assembly depends on a key integrated process, namely, the tail accessory of the connector and the optical cable sheath are permanently sealed by adopting a compression molding vulcanization molding technology. The process aims at forming a continuous and uninterrupted elastic sealing barrier from the connector metal shell to the cable outer jacket, and the scheme has extremely severe requirements on the structural consistency of the cable, the formula and process stability of vulcanized materials and the interface pretreatment, and the defect of any link can lead to watertight failure of the whole assembly. Disclosure of Invention Aiming at the defects existing in the prior art, the invention aims to provide a four-core beam expansion type oil-filled optical fiber connector and an assembling method thereof. The four-core beam expansion type oil-filled optical fiber connector comprises a screw sleeve, a plug shell, four optical fiber beam expansion insulators, a pressure compensator, an oil-filled plug tail clamp, a sealing assembly and a calibration gasket clamped between the oil-filled plug tail clamp and the butt joint end face of the plug shell and used for adjusting the precompression stroke of the pressure compensator; an insulator cavity for accommodating the four optical fiber expanded beam insulators and a compensation cavity for accommodating the pressure compensator are arranged in the plug shell; The screw sleeve is arranged at the front end of the plug shell through a thread connecting sleeve and is used for coaxially fixing the four optical fiber expanding beam insulators in the plug shell and providing initial mechanical pretightening force; The four-fiber beam expansion insulator is arranged in the insulator cavity, is integrated with four independent optical beam expansion channels and is used for realizing signal beam expansion transmission of a four-core optical fiber unit, the outer wall of the four-fiber beam expansion insulator is provided with an integrally formed anti-rotation key, and the anti-rotation key is matched with a key slot on the inner wall of the plug shell; The pressure compensator is arranged in an internal compensation cavity of the plug shell, a uniform annular gap is formed between the outer wall of the pressure compensator and the inner wall of the compensation cavity, and the outer surface of the pressure compensator is coated with compatible silicone grease with the thickness of 0.02-0.05 mm; The oil-filled plug tail clamp is connected with the rear end of the plug shell through threads, the front end of the oil-filled plug tail clamp is used for axially limiting and initially pre-compressing the pressure compensator, and a valve for vacuum extraction, oil filling and final sealing functions is arranged on the side wall of the oil-filled plug tail clamp; The sealing component comprises a polyurethane buffer protection tube sleeved on the four-core optical fiber unit and sleeved on the tail pipe part of the oil-filled plug tail clamp, and a stainless steel double-steel-wire reinforced hose clamp for radially and uniformly compacting and fixing the overlapping area of the polyurethane buffer protection tube and the tail pipe part to form a strain release and anti-kink barrier; The screw sleeve, the plug shell, the four optical fiber beam expansion insulators, the pressure compensator, the oil filling plug tail clamp, the sealing assembly and the calibration gasket are enclosed together to form a completely closed oil filling cavity, and the degassed fluorinated oil or synthetic hydrocarbon oil is injected into the oil filling cavity through a valve and matched with the pressure compensator to construct an active pressure compensation sealing system. The invention is further arranged that the ratio of the precompression stroke of the pressure compensator to the effective axial length of the compensating cavity in the plug shell is 1:12-1:8, and the initial micro positive pressure of the oil filling cavity in the ratio interval under normal pressure can be stably maintained at 0.5-1bar for forming a self-sealing mechanism of active oil extravasation. The pressure compensator is of a stainless steel bellows type elastic structure, the ratio of the effective expansion amount to the free length of the bellows is 1:3-1:5, the ratio of the elastic coefficient of the bellows to the volume of the oil filling cavity is 0.02-0.05MPa/mL, and the pressure compensator is used for realizing rapid dynamic response to environmental pressure change and avoiding sealing failure caused by excessive deformation. Th