Optical fiber sealing joint, contact assembly and connector

Abstract

The invention relates to an optical fiber sealing structure, in particular to an optical fiber sealing joint, a contact assembly and a connector, the contact assembly is arranged in the connector, a sintering shell and an optical cable penetrating through the sintering shell are arranged in the contact assembly, and glass sintering structures are filled in gaps between the sintering shell and the optical cable and gaps among bare optical fibers in the optical cable. The glass sintering structure is a structure formed by heating, melting, extruding and solidifying a glass tube sleeved on the optical cable, a ceramic pressing plate capable of extruding the molten glass tube is arranged in a cavity of the sintering shell, the optical cable penetrates through the ceramic pressing plate, brackets are arranged at two ends of the sintering shell, and an optical fiber contact piece connected with the optical cable is arranged at the other end of each bracket. The optical cable glass sealing optical fiber connector has the advantages of high airtightness and low cost, and the requirements of high airtightness and low loss of the optical cable glass sealing optical fiber connector can be met.

Description

Technical Field

[0001] The invention relates to an optical fiber sealing structure, in particular to an optical fiber sealing joint, a contact component and a connector. Background Art

[0002] Fiber optic sealing joints are products used for coupling various active and passive components and for hermetic sealing between optical fibers and housings. They are widely used in active and passive components in civil high-speed communications, submarine communications, aerospace, and other military and defense fields.

[0003] There are three main solutions for existing optical fiber sealing joints. The first is to use a sealing ring to seal the sleeve and fix the sealing ring to the sleeve with screws, thereby sealing the gap between the optical fiber and the sleeve. The advantages of this solution are high yield and simple processing, but the disadvantages are large size and the need for screws to fix it. The device using this optical fiber sealing joint cannot work in a high-temperature environment. The second solution is to use a gold-plated sleeve on the outside and use glue to seal the optical fiber in the gold-plated sleeve. The advantage of this solution is small size, but it has the disadvantages of poor sealing effect, easy aging, and low resistance to high and low temperature impact. The third solution is to use gold-tin solder to seal the optical fiber after local gold-plating metalization. The advantages of this solution are small size and high sealing reliability, but the disadvantage is high cost. Therefore, the present invention proposes an optical fiber sealing joint with low cost and high sealing reliability. Summary of the Invention

[0004] In order to solve the technical problems of the above optical fiber sealing joint that cannot take into account the volume, operation in high temperature environment, sealing effect and cost, the present invention provides an optical fiber sealing joint and a contact assembly and a connector.

[0005] The objectives of the present invention are achieved by the following technical solutions: A fiber optic sealing joint according to the present invention comprises a housing and an optical cable inserted through the housing. The spaces between the housing and the optical cable, as well as the spaces between the bare optical fibers in the optical cable, are filled with a glass sintered structure. The glass sintered structure is formed by heating, melting, extruding, and solidifying a glass tube sleeved around the optical cable. A ceramic pressure plate capable of extruding the melted glass tube is provided within the housing, and the optical cable is inserted through the ceramic pressure plate.

[0006] Furthermore, the portion of the optical cable passing through the glass tube is a fiber stripping section with the coating removed, and the optical fiber in the fiber stripping section is a bare optical fiber.

[0007] Furthermore, the optical cable and the tube shell are fixed to each other via adhesive at both ends of the tube shell, and the ceramic pressing plate is fixed to the tube shell and the optical cable via adhesive.

[0008] Furthermore, the optical cable is a ribbon optical cable, the glass tube is provided with an optical fiber insertion hole II matching the ribbon optical cable, and the ceramic pressing plate is provided with an optical fiber insertion hole III matching the ribbon optical cable.

[0009] A contact assembly includes a sintered shell and an optical cable inserted into the sintered shell. The gaps between the sintered shell and the optical cable, and the gaps between the bare optical fibers in the optical cable are filled with a glass sintered structure. The glass sintered structure is a structure formed by heating, melting, extruding, and solidifying a glass tube sleeved on the optical cable. A ceramic pressing plate capable of extruding the melted glass tube is provided in the cavity of the sintered shell. The optical cable is inserted into the ceramic pressing plate. Brackets are provided at both ends of the sintered shell, and an optical fiber contact piece connected to the optical cable is provided at the other end of the bracket.

[0010] Furthermore, the portion of the optical cable passing through the glass tube is a fiber stripping section with the coating removed, and the optical fiber in the fiber stripping section is a bare optical fiber.

[0011] Furthermore, the optical cable and the sintered shell are fixed to each other via adhesive at both ends of the sintered shell, and the ceramic pressing plate, the sintered shell and the optical cable are fixed to each other via adhesive.

[0012] Furthermore, the optical cable is a ribbon optical cable, the glass tube is provided with an optical fiber insertion hole II matching the ribbon optical cable, and the ceramic pressing plate is provided with an optical fiber insertion hole III matching the ribbon optical cable.

[0013] A connector includes a shell, a contact assembly is arranged in the shell, and the two ends of the contact assembly are respectively sleeved with a pressure plate I and a pressure plate II. The pressure plate I is respectively welded to the sintered shell and the shell circumference to achieve axial sealing. The shell and the pressure plate II are circumferentially sealed and fixed.

[0014] Furthermore, the plug-in end of the contact assembly is located in the plug-in cavity of the shell, and the bottom edge of the plug-in cavity is provided with a sealing ring for sealing the plug-in interface when plugging with the adapter connector. The outer wall of the shell is provided with a flange for connecting to the bulkhead, and one of the side surfaces of the flange is nested with a sealing ring for sealing with the bulkhead.

[0015] Compared with the prior art, the present invention is beneficial in that:

[0016] After sample trial production and assembly, the leakage rate of the present invention can reach 1×10 -12 Pa·m 3 / s, insertion loss ≤1.2dB. After the connector has been subjected to a temperature shock test of -55℃ to 125℃, the leakage rate and insertion loss indicators still meet the above indicators. This proves that the low-temperature glass-sealed optical fiber sealing joint has the advantages of high airtightness and low cost, and the glass tube and optical fiber glass sintering sealing technology + shell welding sealing technology can achieve the high airtightness and low loss requirements of the optical cable glass-sealed optical fiber connector. The airtight performance that can be achieved by the sealing technology of the present invention is far higher than the current international sealing level of airtight optical fiber connectors, meets the airtightness requirements of existing equipment, and provides an engineering solution for the widespread application of high-density all-optical networks. The present invention can be widely promoted and applied in the fields of coupling of various active and passive devices such as optical transceiver modules and airtight packaging between optical fibers and housings.

[0017] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, which can be implemented in accordance with the contents of the specification, and to make the objects, features and advantages of the present invention more obvious and easy to understand, the following preferred embodiments are specifically cited and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1a A cross-sectional view of an embodiment of an optical fiber sealing joint of the present invention;

[0019] Figure 1b for Figure 1a Front view of the middle glass tube;

[0020] Figure 1c for Figure 1a A three-dimensional diagram of the glass tube in the middle;

[0021] Figure 1d for Figure 1a Schematic cross-section of a ribbon optical cable;

[0022] Figure 1e for Figure 1a Schematic diagram of the cooperation between the middle glass tube and the tube shell;

[0023] Figure 2 A cross-sectional view of a connector embodiment of the present invention;

[0024] Figure 3a for Figure 2 A cross-sectional view of the contact assembly;

[0025] Figure 3b for Figure 2 A cross-sectional view of the contact assembly from another perspective;

[0026] Figure 3c for Figure 3a 3D schematic diagram of

[0027] Figure 4 for Figure 3a Schematic diagram of the optical fiber sealing joint;

[0028] Figure 5 for Figure 3a A cross-sectional view of the contact assembly and the pressure plate 1 in FIG;

[0029] Figure 6 for Figure 3a Schematic diagram of the sealing structure between the contact component and the shell.

[0030] Reference numerals:

[0031] 1- Shell,

[0032] 101-flange,

[0033] 102-insertion cavity I,

[0034] 103-insertion cavity II

[0035] 2- Contact components,

[0036] 21- sintered shell,

[0037] 2101-bonding cavity,

[0038] 2102-sintering chamber,

[0039] 2103-First step I,

[0040] 2104-Second level steps,

[0041] 2105-First Step II,

[0042] 2106-Fiber hole I,

[0043] 2107-bracket mounting slot I,

[0044] 2108-bracket mounting slot II,

[0045] 22- glass tube,

[0046] 2201-Fiber Optic Hole II,

[0047] 23-Ceramic pressure plate,

[0048] 2301-Fiber optic hole III,

[0049] 24-ribbon fiber optic cable,

[0050] 25- Bracket I,

[0051] 2501-key,

[0052] 2502-MT contact mounting slot,

[0053] 2503-support plate,

[0054] 2504-connecting plate,

[0055] 2505-stop protrusion,

[0056] 26-Stand II,

[0057] 27-MT contacts,

[0058] 2701-blocking steps,

[0059] 28- high frequency induction heating position,

[0060] 29-Fiber stripping section,

[0061] 210-Epoxy Adhesive I,

[0062] 211-Epoxy Adhesive II,

[0063] 3-Pressing plate I,

[0064] 301-Welding step I,

[0065] 4-Press Plate II,

[0066] 401-Limited steps,

[0067] 402-Welding Step II,

[0068] 5- rubber ring,

[0069] 6-0 ring,

[0070] 7-Silicone rubber adhesive,

[0071] 8-O-ring installation groove,

[0072] 9-tube shell,

[0073] 901-Fiber optic hole. DETAILED DESCRIPTION

[0074] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0075] An embodiment of an optical fiber sealing joint of the present invention is as follows Figures 1a to 1eThe fiber optic sealing joint comprises a housing 9, a glass tube 22, and a ceramic pressure plate 23. Housing 9 includes a fiber hole 901 for inserting a ribbon optical cable 24. The ribbon optical cable 24 comprises 12 optical fibers. Fiber hole 901 is a waist-shaped hole that matches the outer contour of the ribbon optical cable. A small gap exists between fiber hole 901 and the ribbon optical cable 24 to prevent it from shaking.

[0076] Both ends of the housing 9 are provided with waist-shaped cavities, with an inner contour larger than the optical fiber hole 901. The cavity at the front end of the housing 9 houses the glass tube 22 and ceramic pressure plate 23, through which the optical ribbon cable 24 passes. The glass tube 22 is made of low-temperature glass solder. The glass tube 22 is provided with an optical fiber insertion hole II2201 that matches the outer contour of the optical ribbon cable 24. The optical ribbon cable 24 passes through this waist-shaped hole II2201. The waist-shaped hole in the glass tube 22 is designed to fit a 12-core optical ribbon cable 24, with a small clearance between the holes. The ceramic pressing plate 23 is provided with an optical fiber insertion hole III2301 that matches the outer contour of the ribbon optical cable 24. The ribbon optical cable 24 passes through the optical fiber insertion hole III2301. The optical fiber insertion hole III2301 is also a waist-shaped hole. The size of the waist-shaped hole in the ceramic pressing plate 23 is designed to just pass through the 12-core ribbon optical cable 24.

[0077] The outer contours of the glass tube 22 and the ceramic pressure plate 23 match the inner contour of the front end cavity of the tube shell 9, and are of waist-shaped design. There is a small gap between the glass tube 22, the ceramic pressure plate 23 and the tube shell 9. The wall thickness of the glass tube 22 is uniform at all locations to ensure that the heat experienced by the glass tube at all locations during the sintering process is consistent, and the amount of melted glass is uniform. The ceramic pressure plate 23 is made of ceramic material, and its appearance design is the same as that of the glass tube 22. It has three main functions: ① Protect the ribbon cable 24 during the sintering process, and use the excellent thermal insulation properties of ceramics to reduce the effect of heat on the unstripped coating of the optical fiber in the tube shell 9; ② ​​Apply force from the front end of the ceramic pressure plate 23 during the sintering process to squeeze the molten glass so that the molten glass fully fills the gaps between the optical fibers and the gaps between the optical fibers and the tube shell 9, increasing the density of the glass tube 22 when it melts and solidifies, achieving strict sealing while increasing the strength of the sealing structure, and avoiding The molten glass flows out of the tube shell 9; ③ After sintering, the optical fiber through-hole III2301 of the ceramic pressing plate 23 is used to fit the ribbon cable 24 very closely, extending the length of the small gap fit of the ribbon cable 24 in the tube shell 9 to prevent the optical fiber from breaking. When the contact pieces at both ends of the ribbon cable 24 float, the small gap fit of the ribbon cable 24 and the tube shell 9 of sufficient length can protect the ribbon cable 24 and extend its service life; ④ The glass tube 22 is installed in the tube shell 9 and heated and extruded, and the molten glass fills the spaces between the optical fibers and between the optical fibers and the tube shell. The gap will inevitably leave a cavity in the shell, and the length of the ceramic pressing plate 23 can be appropriately increased. After the glass tube 22 and the ceramic pressing plate 23 are inserted into the shell 9, the ceramic pressing plate 23 protrudes from the shell 9. After heating and extrusion, the ceramic pressing plate 23 can further enter the shell 9. After solidification, the ceramic pressing plate 23 is flush with the end face of the shell 9 or protrudes from the end face of the shell 9, ensuring that the cavity inside the shell 9 is filled, supporting the shell 9, and improving the overall strength of the shell 9. In addition, the melted glass will enter the internal gap of the ceramic pressing plate 23 near the glass tube 22 ⑤ After the glass tube 22 is heated and melted, the position of the ribbon cable 24 is prone to deflection. The ceramic pressing plate 23 can be used to set the ribbon cable 24 in the middle of the tube shell 9. ⑥ When the tube shell 9 is processed and in use, the mechanical stress and / or adhesive temperature stress of itself or the outside world directly acts on the ceramic pressing plate 23, and is not directly transmitted to the glass sintered structure formed by the glass tube 22, thereby protecting the glass sintered structure.

[0078] Before the 12-core ribbon optical cable 24 is inserted into the tube shell 9, the middle section of the ribbon optical cable 24 is stripped of the sheath, coating, etc. to form a fiber stripping section 29, that is, a section of optical fiber at the fiber stripping section 29 is a bare optical fiber. After the ribbon optical cable 24 is inserted into the tube shell 9, the fiber stripping section 29 can be located in the glass tube 22, that is, the optical fiber of the ribbon optical cable 24 located at the glass tube position is stripped into a bare optical fiber without a coating layer and then inserted into the tube shell 9.

[0079] After the ribbon cable 24 is inserted into the tube shell 9, the stripped optical fiber section 29 with the coating removed is placed at the installation position of the glass tube 22. A silicone rubber adhesive 7 is provided in the cavity at the rear end of the tube shell 9 for pre-fixing the ribbon cable 24.

[0080] After the ribbon optical cable 24 is pre-fixed, the glass tube 22 and the ceramic pressing plate 23 are sequentially installed into the tube shell 9 from the front end.

[0081] The glass tube 22 is heated by a high-frequency induction heating process (for example, a high-frequency induction coil is sheathed outside the tube shell 9 at the position of the glass tube 22), and a force is applied to the ceramic pressing plate 23 from the front end of the tube shell 9. The ceramic pressing plate 23 squeezes the melted glass tube 22, so that the glass tube 22 melts and fills the gap between the ribbon optical cable 24 and the inner wall of the tube shell 9 and the gap between the bare optical fibers in the ribbon optical cable 24 and solidifies. The structure formed by the melting, filling and solidification of the glass tube 22 is a glass sintered structure. The glass sintered structure and the ribbon optical cable 24 are connected. The optical fiber stripping section 29 and the tube shell 9 are integrally arranged to achieve good airtightness. The optical fiber stripping section 29 removes the coating layer to avoid local damage or peeling of the optical fiber coating layer here, thereby avoiding the formation of a new leakage channel between the bare optical fiber and the coating layer. In this embodiment, the ceramic pressing plate 23 is squeezed until the front end of the ceramic pressing plate 23 is flush with the front end of the tube shell 9, so that the glass tube 22 is melted and the ribbon optical cable 24 and the tube shell 9 are solidified into one. The airtightness between the ribbon optical cable 24 and the tube shell 9 is achieved by the glass sintering structure between the tube shell 9 and the ribbon optical cable 22.

[0082] The front and rear ends of the sintered optical fiber sealing joint are bonded and fixed with epoxy adhesive I210 and epoxy adhesive II211 respectively, so that the ribbon optical cable 24 inside the optical fiber sealing joint is relatively fixed to the tube shell 9. When the optical fiber sealing joint vibrates in the use environment, or the optical fiber sealing joint is used for a connector and the connector vibrates when plugging and unplugging, the bare optical fiber at the sintering position can be prevented from being broken by stress, thereby protecting the ribbon optical cable 24.

[0083] The tube shell 9 can be made of stainless steel and sealed with the sealing component by laser welding or electron beam welding. The tube shell 9 can also be made of gold-plated tube shell and sealed with the sealing component by gold-tin welding.

[0084] Fiber optic sealing joints can be used in active devices such as optical modules or passive components such as optical connectors. When an optical fiber needs to pass through the housing of an optical module, the fiber optic sealing joint is placed on the housing and welded to the housing to achieve a seal. When sealing is required at the front and rear ends of a fiber optic connector, the fiber optic sealing joint can be used to seal the contact components within the connector. Fiber optic sealing joints can also be used in other structures requiring a seal between the optical fiber and the housing.

[0085] In other embodiments, the shapes and sizes of the tube shell 9, glass tube 22, and ceramic pressure plate 23 in the optical fiber sealing joint can be adjusted according to specific needs. For example, when it is necessary to use optical fibers with specifications such as 24 cores and 48 cores, that is, when two, four, or the like 12-core ribbon optical cables 24 are required, a corresponding number of waist-shaped holes for the ribbon optical cables 24 to pass through can be provided on the tube shell 9, glass tube 22, and ceramic pressure plate 23; or, if it is necessary to set two ribbon optical cables 24, two optical fiber insertion holes II2201 can be provided on one glass tube 22, and two optical fiber insertion holes II2201 can be provided on one glass tube 22. Two optical fiber insertion holes III2301 are set on each ceramic pressure plate 23, and two optical fiber ribbon cables 24 share one glass tube 22 and one ceramic pressure plate 23, and the glass tube 22 and the ceramic pressure plate 23 are inserted into the corresponding cavity of the tube shell 9; if four optical fiber ribbon cables 24 are needed, two glass tubes 22 with two optical fiber insertion holes II2201 and two ceramic pressure plates 23 with optical fiber insertion holes III2301 can be set in the tube shell 9, and the two glass tubes 22 and the ceramic pressure plates 23 are respectively inserted into the corresponding cavities of the tube shell 9.

[0086] In other embodiments, after the ribbon optical cable 24 is pre-fixed by the silicone rubber adhesive 7, the epoxy adhesive II211 can be set at the rear end of the tube shell 9 to firmly fix the ribbon optical cable 24 on the tube shell 9, and then sintering is performed. During sintering, the silicone rubber adhesive 7 can play a sealing role to prevent the epoxy adhesive from directly contacting the glass being sintered. After the epoxy adhesive is in direct contact with the glass and in a high or low temperature environment, the stress of the epoxy adhesive may cause the glass to break, affecting the sealing effect.

[0087] In other embodiments, the epoxy adhesive may be replaced with other adhesives capable of bonding the ribbon optical cable 24 , the tube housing 9 , and the ceramic pressing plate.

[0088] In other embodiments, the ribbon optical cable 24 may also be replaced with other forms of optical cables, such as a bundled optical cable, and the structure that cooperates with the optical cable matches the outer profile of the bundled optical cable.

[0089] An embodiment of a connector of the present invention, such as Figures 2 to 6 The connector includes a contact assembly 2, a housing 1, a pressure plate I3, and a pressure plate II4 capable of achieving airtightness. Figure 2 shown.

[0090] Both ends of the housing 1's interior cavity are mating cavities, namely, mating cavity I 102 and mating cavity II 103. Rubber rings 5 ​​are installed at the bottom edges of the cavities. When the connector is mated with the mating connectors inside and outside the bulkhead, the rubber rings 5 ​​seal the mating interface. The connector is mounted on the bulkhead via a flange 101 on the outer wall of the housing 1, and the mounting interface is sealed with the bulkhead via an O-ring 6. In this embodiment, the O-ring 6 is nested in one side of the flange 101. When the connector is mounted on the bulkhead, the flange 101 rests against the outer surface of the bulkhead. The O-ring seals the flange 101 and the bulkhead together. The side facing the O-ring 6 is considered the rear side in this description.

[0091] The reliable sealing inside the connector requires the airtightness of all leakage channels. The connector has two leakage channels, namely the leakage channel inside the contact component 2 and the leakage channel between the contact component 2 and the shell 1. Therefore, the airtight performance of the connector includes the airtightness of the internal contact component 2 and the airtightness between the contact component 2 and the shell 1.

[0092] The airtight seal inside the contact assembly 2 is mainly achieved by the above-mentioned optical fiber sealing joint. The structural design of the contact assembly 2 is as follows: Figure 3a 、 Figure 3b 、 Figure 3c As shown, the contact assembly 2 includes two 12-core MT contacts 27 at each end, two brackets (Bracket I 25 and Bracket II 26), a sintered housing 21, a glass tube 22, a ceramic pressure plate 23, and a 12-core ribbon cable 24. The fiber sealing joint includes the sintered housing 21, glass tube 22, and ceramic pressure plate 23. The sintered housing 21 is the tube housing 9 in the aforementioned fiber sealing joint embodiment, modified to adapt to the structural characteristics of the connector. The 12-core ribbon cable 24 enables 12-core signal transmission, with a 12-core MT contact connected to each end of the ribbon cable 24.

[0093] When making the contact assembly 2, first, the sheath, coating, etc. of the middle section of the ribbon optical cable 24 are stripped off, that is, the ribbon optical cable 24 at the position of the glass tube 22 is stripped into a bare optical fiber without a coating, and then the ribbon optical cable 24 is inserted into the optical fiber passage hole 12106 in the sintered shell 21. The optical fiber passage hole 12106 is a waist-shaped hole. The inner diameter of the optical fiber passage hole 12106 matches the outer size of the ribbon optical cable 24 and is a small gap fit to prevent the ribbon optical cable 24 from shaking in the optical fiber passage hole 12106.

[0094] A sintering cavity 2102 and a bonding cavity 2101 are respectively provided at the front and rear ends of the sintered shell 21. The sintering cavity 2102 and the bonding cavity 2101 are connected through an optical fiber through hole I2106. After the ribbon optical cable 24 is passed through the optical fiber passing hole I2106, the silicone rubber adhesive 7 and the epoxy adhesive II211 are used to fix the ribbon optical cable 24 to the sintered shell 21 at the rear end of the sintered shell 21. In this embodiment, the silicone rubber adhesive 7 and the epoxy adhesive II211 are poured into the bonding cavity 2101, wherein part of the epoxy adhesive II211 is arranged outside the bonding cavity 2101 and located on the rear end surface of the sintered shell 21, thereby firmly fixing the ribbon optical cable 24; then, the glass tube 22 and the ceramic pressure plate 23 are sequentially installed into the sintering cavity 2102 at the front end of the sintered shell 21 from the front end of the sintered shell 21, and the inner contour dimensions of the sintering cavity 2102 match the outer contour dimensions of the glass tube 22 and the glass pressure plate 23, and are a small gap fit. The ribbon optical cable 24 is inserted into the optical fiber passage hole II2201 of the glass tube 22 and the optical fiber passage hole III2301 of the ceramic pressure plate 23. The optical fiber passage hole II2201 and the optical fiber passage hole III2301 are both waist-shaped holes, which match the outer contour size of the ribbon optical cable 24 and are fitted with a small gap.

[0095] After the ribbon cable 24 is passed through the glass tube 22, the optical fiber stripping section 29 of the ribbon cable 24 with the coating stripped is located in the optical fiber passing hole II2201 of the glass tube 22. Figure 4 The high-frequency induction heating position 28 shown uses a high-frequency induction coil to heat, causing the glass tube 22 there to melt simultaneously. During the sintering process, the ceramic pressing plate 23 is pressed, squeezing the melted glass tube 22, allowing the molten glass in the glass tube 22 to flow fully into the gaps between the bare optical fibers in the ribbon cable 24 and the gap between the ribbon cable 24 and the sintered shell 21, preventing leaks. The stripped fiber section 29 of the ribbon cable 24 and the sintered shell 21 are solidified into one piece through the glass tube 22, thereby achieving a seal within the contact assembly 2. After the glass is sintered, the stripped fiber section 29 of the ribbon cable 24 is integrated with the sintered shell 21 through the glass, achieving a good airtight seal, preventing local damage or peeling of the optical fiber coating at this location, and thus preventing the formation of new leakage channels between the bare optical fiber and the coating.

[0096] The wall thickness of the sintering shell 21 at the sintering position is uniform, thereby ensuring that the glass tube 22 is subjected to uniform heat at all locations during sintering. During sintering, the high-frequency induction heating position 28 of the sintering shell 21 (where the glass tube 22 is located) is entirely placed in the high-frequency induction coil.

[0097] Finally, the ceramic pressure plate 23 is bonded and fixed to the front end of the ribbon optical cable 24 and the sintered shell 21 using epoxy adhesive I210. When the connector is plugged in, the MT contact 27 is subjected to force, which can easily cause the ribbon optical cable 24 to shake, and then easily transmit force to the junction of the bare optical fiber and the glass, which can easily cause the optical fiber to break and affect the transmission of optical signals. The ribbon optical cable 24 and the sintered shell 21 are fixed together by epoxy adhesive I210 and epoxy adhesive II211 to prevent the ribbon optical cable 24 from breaking.

[0098] Both ends of the exterior of the sintered shell 21 are provided with installation steps. The front end of the sintered shell 21 is provided with two installation steps, namely the first step I2103 and the second step 2104 , and the rear end of the sintered shell 21 is provided with a first step II2105 .

[0099] Brackets I25 and II26 are provided at both ends of the sintered shell 21, respectively. MT contacts 27 are provided at the other ends of both brackets I25 and II26. Brackets I25 and II26 have identical structures, and one of them will be used as an example for illustration. Bracket I25 includes two support plates 2503 arranged opposite each other and extending forward and backward. One side of the two support plates 2503 is connected to each other via a connecting plate 2504, thereby connecting the two support plates 2503 into a single piece. Keys 2501 are provided on the ends of both support plates 2503 proximal to the sintered shell 21, and the two keys 2501 are arranged opposite each other. Two bracket mounting grooves I2107 are symmetrically provided on the outer wall of the first step I2103 of the sintered shell 21. The keys 2501 cooperate with the bracket mounting grooves I2107 to achieve positioning and are then fixed by bonding. When installing bracket I25 on the sintered shell 21, push the key 2501 on bracket I25 from one side of the bracket installation slot I107 into the bracket installation slot I. The ends of the two support plates 2503 are clamped on the outside of the sintered shell 21. The key on bracket II26 is installed in the bracket installation slot II2108 on the first step II2105.

[0100] The cavity between the two support plates 2503 forms an MT contact mounting slot 2502. Stopping protrusions 2505 are provided on both sides of the MT contact mounting slot 2502. An MT contact 27 is mounted within the MT contact mounting slot 2502. Stopping steps 2701 are provided on the outer walls of the MT contact 27. The rear end of the MT contact 27 and the stopping steps 2701 are positioned between the stopping protrusions 2505 at the front and rear ends of the MT contact mounting slot 2502, limiting the front-to-back position of the MT contact 27. To install the MT contact 27, push it into the MT contact mounting slot 2502 from one side, making installation quick and easy, and facilitating positioning of the MT contact 27. The dimensions between the rear end face of the MT contact 27 and the stop step 2701 provide a close clearance fit with the corresponding front and rear stop protrusions 2505. The thickness of the MT contact 27 also provides a close clearance fit with the opposing side walls of the two support plates 2503. The mating end of the MT contact 27 extends out of the MT contact mounting slot 2502. Another MT contact 27 is mounted on the bracket II 26. The floating structure with a close clearance fit between the MT contact 27 and the bracket allows for adequate movement within the MT contact mounting slot 2502, ensuring self-adjustment during mating and effectively reducing the connector's insertion loss.

[0101] After the contact assembly 2 is completed with glass sintering seal and the bracket and MT contact 27 are assembled, it is assembled into one piece with the pressing plate 13. Figure 5 As shown, the pressure plate I3 is a cylindrical body with an inner hole. The front end of the sintered shell 21 is installed in the inner hole of the pressure plate I3, and the inner hole of the pressure plate I3 is sleeved on the secondary step 2104. The two are matched with a small gap. The pressure plate I3 is welded to the sintered shell 21. The maximum outer circle of the sintered shell 21 is consistent with the outer circle of the welding point of the pressure plate I3. Circumferential laser welding (or electron beam welding) is used at the joint between the sintered shell 21 and the pressure plate I3 to achieve axial sealing (i.e., the direction in which the ribbon cable 24 extends). To reduce the impact of welding heat on the sintered sealing structure, the weld is welded in four sections. The pressure plate I3 can be sleeved on the bracket I25 to prevent the MT contact 27 from falling out of the MT contact mounting slot 2502, and the plug-in end of the MT contact 27 extends out of the pressure plate I3.

[0102] After the contact assembly 2 is welded to the pressure plate I3, it is installed in the shell 1. The front end of the pressure plate I3 extends out of the bottom surface of the plug-in cavity I102. The outer wall of the pressure plate I3 is provided with a welding step I301. The welding step I301 is flush with the bottom surface of the plug-in cavity I102 and circumferential laser welding (or electron beam welding) is used to achieve axial sealing. In order to further improve the airtightness, corresponding O-ring mounting grooves 8 can also be provided on the outer wall of the pressure plate I3 and the inner wall of the shell 1. Axial sealing is achieved by arranging an O-ring in the O-ring sealing groove 8. In this embodiment, two O-ring mounting grooves 8 are distributed in the axial direction on the outer wall of the pressure plate I3 and the inner wall of the shell 1. O-rings are installed in the O-ring mounting groove 8 to achieve two-stage O-ring sealing.

[0103] Pressing plate II 4 is inserted into housing 1 from its rear end. It is a cylindrical body with an inner hole. The inner hole of pressing plate II 4 fits over sintered housing 21 and bracket II 26. The mating end of MT contact 27 on bracket II 26 extends out of pressing plate II 4. A stop step 401 is provided on the outer wall of pressing plate II 4 to stop against the inner wall of housing 1, limiting the forward movement of pressing plate II 4. Before the outer wall of the pressure plate II 4 is installed in the shell 1, an adhesive can be provided on the outer wall of the pressure plate II 4 and / or the inner wall of the shell 1. After the pressure plate II 4 is installed and the adhesive is cured, the pressure plate II 4 is bonded and fixed to the shell 1 and an axial seal is achieved; alternatively, after the pressure plate II 4 is installed in the shell 1, the welding step II 402 of the outer wall of the pressure plate II 4 is flush with the bottom surface of the insertion cavity 102, and the pressure plate II 4 can be welded and fixed in the shell 1 to achieve axial sealing. The welding method is the same as that of the pressure plate I 3, such as Figure 6 shown.

[0104] After the pressure plate II4 is installed, rubber rings 5 ​​are provided at the bottom of the insertion cavity at the front and rear ends of the housing 1, and an O-ring is provided on the flange 101.

[0105] In other embodiments of a connector of the present invention, an O-ring may be used to further seal between the pressure plate II4 and the housing 1, and an adhesive may be used to further seal between the pressure plate I3 and the housing 1.

[0106] In other embodiments of a connector of the present invention, different numbers and core counts of ribbon optical cables can be selected as needed. Correspondingly, the sintered shell 21 is designed with fiber optic insertion holes, sintering cavities, and bonding cavities of corresponding numbers and sizes. A glass tube and a ceramic pressure plate are installed in the sintering cavity. The glass tube can be a double-cavity glass tube (with two fiber optic insertion holes) or a single-cavity or multi-cavity glass tube (with one or more fiber optic insertion holes). The size of the fiber optic insertion hole of the glass tube is designed according to the size of the ribbon optical cable. The ceramic pressure plate can be a double-cavity ceramic pressure plate (with two fiber optic insertion holes) or a single-cavity or multi-cavity ceramic pressure plate (with one or more fiber optic insertion holes). The size of the fiber optic insertion hole of the ceramic pressure plate is designed according to the size of the ribbon optical cable. The end of the bracket is installed with MT contacts 27 of corresponding core number and number according to the core number and number of the ribbon optical cable 12.

[0107] In other embodiments of a connector of the present invention, the ribbon optical cable 24 can be replaced by other forms of optical cables, such as bundled optical cables, and the structure that cooperates with the optical cable matches the outer profile of the bundled optical cable.

[0108] In other embodiments of a connector of the present invention, the MT contact may be replaced by other forms of optical fiber contacts.

[0109] In other embodiments of a connector of the present invention, the rubber ring 5 and the O-ring can be replaced with other types of sealing rings.

[0110] The technical features of a connector of the present invention are as follows:

[0111] ① The present invention designs a glass tube that matches the outer dimensions of a 12-core ribbon optical cable 24 and a sintered shell 21 having a sintering cavity that matches the glass tube. High-frequency induction local heating is used to achieve sealing between the glass tube 22, the 12-core optical fiber, and the sintered shell 21.

[0112] ② The present invention designs a ceramic pressing plate 23. During the glass sintering process, the ceramic pressing plate 23 protects the ribbon cable 24 and ensures that the gaps in the ribbon cable 12 are fully filled with glass;

[0113] ③ The present invention realizes floating docking of the MT contact 27 through the floating structure of the bracket and the MT contact 27;

[0114] ④ Laser welding or electron beam welding is used between the contact assembly 2 and the pressure plate, and between the pressure plate and the housing 1 of the present invention to melt the metal matrix into one body, thereby achieving sealing;

[0115] ⑤ The tube shell 9 and the sealing component of the present invention can be sealed in a variety of ways and have a wide range of applications;

[0116] ⑥ The glass seal of the present invention has a low-cost advantage compared to the high price of gold-tin solder.

[0117] After sample trial production and assembly, the leakage rate of the present invention can reach 1×10 -12 Pa·m 3 / s, insertion loss ≤1.2dB (insertion loss of two docking points, that is, the insertion loss of two docking points formed after both ends of the connector are docked with the matching device). After the connector has been subjected to a temperature shock test of -55℃ to 125℃, the leakage rate and insertion loss indicators still meet the above indicators. This proves that the low-temperature glass-sealed optical fiber sealing joint has the advantages of high airtightness and low cost, and the glass tube and optical fiber glass sintering sealing technology + shell welding sealing technology can achieve the high airtightness and low loss requirements of the 12-core ribbon cable glass-sealed optical fiber connector. The airtight performance that can be achieved by the sealing technology of the present invention is far higher than the current international sealing level of airtight optical fiber connectors, meets the airtightness requirements of existing equipment, and provides an engineering solution for the widespread application of high-density all-optical networks. The present invention can be widely promoted and applied in the fields of coupling of various active and passive devices such as optical transceiver modules and airtight packaging between optical fibers and housings.

[0118] An embodiment of a contact assembly of the present invention is the contact assembly in the embodiment of the connector described above, and will not be described in detail here.

[0119] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and alterations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An optical fiber sealing joint, comprising a housing (9) and an optical cable passing through the housing (9), characterized in that: The gaps between the tube shell (9) and the optical cable and the gaps between the bare optical fibers in the optical cable are filled with a glass sintered structure. The glass sintered structure is a structure formed by heating, melting, extruding, and solidifying a glass tube (22) sleeved on the optical cable. A ceramic pressing plate (23) capable of extruding the melted glass tube (22) is provided in the cavity of the tube shell (9), and the optical cable is passed through the ceramic pressing plate (23).

2. The optical fiber sealing joint according to claim 1, characterized in that: The portion of the optical cable passing through the glass tube (22) is a fiber stripping section (29) with the coating removed, and the optical fiber in the fiber stripping section (29) is a bare optical fiber.

3. The optical fiber sealing joint according to claim 1, characterized in that: The optical cable and the tube shell (9) are fixed to each other via adhesive at both ends of the tube shell (9), and the ceramic pressing plate (23) is fixed to the tube shell (9) and the optical cable via adhesive.

4. The optical fiber sealing joint according to claim 1, characterized in that: The optical cable is a ribbon optical cable (24); the glass tube (22) is provided with an optical fiber insertion hole II (2201) matching the ribbon optical cable (24); and the ceramic pressing plate (23) is provided with an optical fiber insertion hole III (2301) matching the ribbon optical cable (24).

5. A contact assembly comprising a sintered housing (21) and an optical cable passing through the sintered housing (21), characterized in that: The gaps between the sintered shell (21) and the optical cable and the gaps between the bare optical fibers in the optical cable are filled with a glass sintered structure. The glass sintered structure is a structure formed by heating, melting, extruding, and solidifying a glass tube (22) sleeved on the optical cable. A ceramic pressing plate (23) capable of extruding the melted glass tube (22) is provided in the cavity of the sintered shell (21). The optical cable is passed through the ceramic pressing plate (23). Brackets are provided at both ends of the sintered shell (21), and an optical fiber contact piece connected to the optical cable is provided at the other end of the bracket.

6. A contact assembly according to claim 5, characterized in that: The portion of the optical cable passing through the glass tube (22) is a fiber stripping section (29) with the coating removed, and the optical fiber in the fiber stripping section (29) is a bare optical fiber.

7. The contact assembly according to claim 5, characterized in that: The optical cable and the sintered shell (21) are fixed to each other via adhesive at both ends of the sintered shell (21), and the ceramic pressing plate (23) is fixed to the sintered shell (21) and the optical cable via adhesive.

8. The contact assembly according to claim 5, characterized in that: The optical cable is a ribbon optical cable (24); the glass tube (22) is provided with an optical fiber insertion hole II (2201) matching the ribbon optical cable (24); and the ceramic pressing plate (23) is provided with an optical fiber insertion hole III (2301) matching the ribbon optical cable (24).

9. A connector, comprising a housing (1), characterized in that: A contact assembly (2) according to any one of claims 5 to 8 is arranged in the shell (1), and a pressure plate I (3) and a pressure plate II (4) are respectively sleeved on the two ends of the contact assembly (2), and the pressure plate I (3) is respectively welded and fixed to the sintered shell (21) and the shell (1) in a circumferential manner to achieve axial sealing, and the shell (1) and the pressure plate II (4) are circumferentially sealed and fixed.

10. The connector according to claim 9, characterized in that: The plug-in end of the contact assembly (2) is located in the plug-in cavity of the housing (1); a sealing ring is provided on the bottom edge of the plug-in cavity for sealing the plug-in interface when plugged into the adapter connector; the outer wall of the housing (1) is provided with a flange (101) for connecting to the bulkhead; one side of the flange (101) is embedded with a sealing ring for sealing with the bulkhead.

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