Optical fiber assembly and heavy-duty connector

Abstract

The present invention provides an optical fiber assembly and a heavy-duty connector, the optical fiber assembly includes a plug and a socket, wherein the plug includes a head shell and a head inner shell, an optical fiber contact is installed in the head inner shell, the plug end is the front end, the head shell is a square structure as a whole, the head inner shell includes a small square section located at the front section and a large square section coaxially arranged behind the small square section, the large square section is accommodated in the head shell, and the small square section passes out of the head shell; the socket includes a seat shell, the seat shell is a stepped square structure as a whole, an optical fiber contact is installed in the seat shell, the front section of the seat shell is provided with a square hole plugged with the small square section, and the seat shell and the head inner shell are plugged through an adapted square interface. The optical fiber assembly adopts a square structure as a whole, and adopts a square interface, and is compact.

Description

Technical Field

[0001] The present invention relates to the technical field of heavy-duty connectors, and in particular to an optical fiber assembly and a heavy-duty connector. Background Art

[0002] Heavy-duty connectors, also known as HDC heavy-duty connectors, can directly connect the electrical equipment module lines on both sides, which is convenient for modular manufacturing of electrical equipment and can effectively prevent wiring errors. During on-site installation, only the connection work of the heavy-duty connector is required. The installation is simple, efficient, and easy to maintain. It can adapt to normal work in complex and harsh environments. It is widely used in construction machinery, textile machinery, packaging and printing machinery, tobacco machinery, robots, rail transportation, hot runners, electric power, automation and other equipment that require electrical and signal connections.

[0003] At present, heavy-duty connectors are mostly used outdoors and in harsh environments such as high vibration and impact. There are extremely high requirements for the mechanical life, vibration, impact and dirt resistance of optical fiber components. If the connector itself does not have a certain degree of vibration, impact and dirt resistance, the connector body is easily damaged, eventually causing certain losses.

[0004] Moreover, existing heavy-duty connectors require more and more wiring cores to connect the devices on both sides. The increase in the number of cable cores makes the heavy-duty connector larger in size and requires a larger space, which will cause the heavy-duty connector to be too large and is not conducive to the miniaturization of the product.

[0005] Meanwhile, the heavy-duty connector generally includes a fixed frame and an optical fiber assembly adapted to be mounted thereon, such as the attachment of the utility model patent with publication number CN218919299U. Figure 1 and the attached utility model patent with publication number CN202352910U Figure 1 It can be seen that the cross-section of the installation cavity in the fixed frame for installing the optical fiber assembly is rectangular. How to ensure that the improved optical fiber assembly still fits into the rectangular installation cavity of the original fixed frame is also a problem that technicians need to consider.

[0006] The purpose of the present invention is to solve the above problems and to provide a heavy-duty connector which is compact, resistant to high vibration, impact and dirt and suitable for harsh outdoor environments. Summary of the invention

[0007] In view of this, an object of the present invention is to provide an optical fiber assembly and a heavy-duty connector. The optical fiber assembly adopts a cubic structure as a whole and a square interface, and is compact in size.

[0008] The technical solution adopted by the present invention to solve the above technical problems is: In one aspect, the present invention provides an optical fiber assembly, comprising: The plug comprises a head outer shell and a head inner shell, wherein an optical fiber contact is installed in the head inner shell, and the plug end is the front end, the head outer shell is a square structure as a whole, and the head inner shell comprises a small square section located at the front section, and the small square section passes through the head outer shell; The socket comprises a socket shell, which is in a square structure as a whole. An optical fiber contact is installed in the socket shell. A square hole is provided in the front section of the socket shell to be plugged into the small square section. The socket shell and the head inner shell are plugged into each other through a matching square interface.

[0009] Furthermore, at least one guide hole extending forward and backward is provided at the front of the small cube segment, and a guide pin matching the guide hole is provided on the rear wall of the square hole.

[0010] Furthermore, two adjacent side surfaces of the small cube segment are connected by arc segments, and the curvatures of at least two arc segments are different.

[0011] Furthermore, the head inner shell and the seat outer shell are each provided with at least one optical fiber mounting hole extending in the front-to-back direction, and a mounting groove connected to the rear end of at least one optical fiber mounting hole; the optical fiber contact piece is installed in the optical fiber mounting hole by a top stop positioning structure.

[0012] Furthermore, a conical chamfer is provided at the front end of the optical fiber installation hole.

[0013] Furthermore, the top stop positioning structure includes a positioning spring installed in the optical fiber installation hole and a limiting sleeve installed on the outer wall of the optical fiber contact piece. The positioning spring and the limiting sleeve cooperate to position the optical fiber contact piece.

[0014] Furthermore, a cover plate for fixing a positioning clip is installed in the installation groove, a positioning groove is provided on the side wall of the installation groove, and a positioning block matching the positioning groove is provided on the side wall of the cover plate.

[0015] Furthermore, an axial spring and a limit plate are provided in the head outer shell, and the limit plate is fixed to the tail of the head outer shell. The front end of the axial spring presses against the head inner shell, and the rear end presses against the limit plate.

[0016] Furthermore, cylindrical grooves for limiting the axial spring are provided on the opposite end surfaces of the head inner shell and the limiting plate.

[0017] Furthermore, a protrusion is provided at the rear end of the limiting plate, and a groove matching the protrusion is provided at the rear end of the head shell.

[0018] Furthermore, the small cube segment is provided with a limit key extending forward, which cooperates with the limit groove on the head outer shell to prevent the head inner shell from deflecting in the head outer shell.

[0019] Furthermore, the optical fiber assembly also includes a sealing structure, which includes a first-level sealing structure arranged at the tail of the head inner shell and / or the seat outer shell for sealing the wire, and a second-level sealing structure arranged at the front end of the socket for plugging and cooperating with the plug-in end of the plug to seal the interface between the two in the plugged state.

[0020] Furthermore, the first-level sealing structure includes a sealing body arranged behind the cover plate, and the sealing body is glued and fixed to the cover plate.

[0021] Furthermore, the second-level sealing structure is an interface sealing gasket arranged close to the rear wall of the square hole in the socket, and a conical elastic protrusion is provided on the front end surface of the interface sealing gasket at a position corresponding to the installation of the optical fiber contact piece.

[0022] On the other hand, the present invention provides a heavy-duty connector, including a fixing frame and an optical fiber assembly installed in a rectangular installation cavity in the fixing frame.

[0023] Furthermore, a boss is provided on the outer wall of the head shell and / or the seat shell, and a groove which matches the boss gap is provided on the inner wall of the fixed frame to ensure that the optical fiber assembly can float along the fixed frame.

[0024] Beneficial effects: As described above, an optical fiber assembly and a heavy-duty connector of the present invention have the following beneficial effects: (1) The present invention designs the head inner shell and the seat outer shell into a square structure, and the head seat adopts a square interface for plugging. Compared with the use of a circular interface, it occupies less space, and when using optical fiber contacts of the same specification, the number of square interfaces arranged is greater, and the contact density is high. That is, the connector in the present invention has a high contact density while reasonably utilizing the installation space and ensuring the required functions, which can facilitate the expansion of optical fiber capacity in the same module.

[0025] (2) The entire head shell and the rear section of the seat shell are designed to be a square structure, which can be installed in the rectangular installation cavity of the original fixed frame without adjusting the structure of the fixed frame.

[0026] (3) The head inner shell of the present invention comprises a small cube section located at the front section and a large cube section coaxially arranged behind the small cube section. A limit key extending forward is provided on the annular stop surface formed at the connection position between the small cube section and the large cube section. This key prevents the head inner shell from rotating inside the head outer shell after assembly, thereby playing a limiting role.

[0027] (4) In the present invention, two adjacent side surfaces of the small cube segment are connected by arc segments, and there are four arc segments in total. The curvatures of the four arc segments are not completely the same. In this way, the precise positioning function and blind plug-in function of the plug and the socket can be achieved.

[0028] (5) In order to minimize the gap generated when installing the plug and reduce costs, the inner shell of the head is formed in one piece, combining the functions of an ordinary shell and an insulator into one. The inner cavity of the shell is machined with a fiber optic mounting hole for fixing the fiber optic contact, which can reduce the number of installation parts and reduce the installation gap.

[0029] (6) The present invention has at least one guide hole extending forward and backward at the front of the small cube segment, and a guide pin is provided at the front end of the square hole in the housing, which can ensure the stability of the connector docking. Conventionally, circular connectors use keys and keyways to achieve the guiding function, while the rectangular connector itself has a chamfered shell to achieve preliminary positioning and guiding. However, due to the importance of guiding the optical fiber connector, the present invention adds the guidance of the guide pin, and the guiding sequence during the insertion is shell-guide pin-optical fiber contact, which reduces the matching clearance of the module docking, prevents excessive axial deflection, and ensures the centering of the optical fiber.

[0030] (7) The optical fiber contact of the present invention is positioned in the optical fiber mounting hole of the head inner shell or the seat outer shell by a top stop positioning structure. When a removal tool is used to act on the top stop positioning structure, the optical fiber contact can be easily removed from the shell, thereby greatly improving the maintainability of the connector and having single-point maintainability of the optical cable.

[0031] (8) The optical fiber assembly of the present invention also includes a sealing structure, which can not only ensure the sealing of the wire outlet part of the connector tail to prevent external dust, liquid and harmful gas from invading the inside of the plug or socket, but also form a sealing barrier between the optical fiber contacts, so that each pair of mating optical fiber contacts can achieve a sealing effect, thereby improving the environmental resistance of the connector.

[0032] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 is a schematic diagram of an optical fiber assembly in the present invention.

[0035] Figure 2 This is one of the axonometric views of the plug.

[0036] Figure 3 This is the second axonometric view of the plug.

[0037] Figure 4is a cross-sectional view of the plug.

[0038] Figure 5 It is a schematic diagram of the head inner shell, axial spring and limit plate.

[0039] Figure 6 is a schematic diagram of a limit plate.

[0040] Figure 7 This is an axonometric view of the socket.

[0041] Figure 8 is a cross-sectional view of the socket.

[0042] Fig. 9 Schematic diagram of the housing.

[0043] Markings in the diagram: 1. seat shell; 101. square hole; 2. head shell; 201. limiting groove; 202. groove; 3. head inner shell; 3-1. small cube segment; 3-2. large cube segment; 301. guide hole; 302. limiting key; 4. cover plate; 401. positioning block; 5. sealing body; 501. drum-shaped step hole; 6. optical fiber contact; 7. boss; 8. limiting plate; 801. bump; 9. axial spring; 10. positioning retaining spring; 1001. spring piece; 11. cylindrical groove; 12. optical fiber mounting hole; 13. mounting groove; 1301. positioning groove; 14. guide pin; 15. interface sealing gasket; 1501. conical elastic protrusion; 16. limiting sleeve. DETAILED DESCRIPTION

[0044] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the protection scope of the present invention.

[0045] In the description of the present invention, it should be understood that the directions or positional relationships indicated by "upper" and "lower" in the art are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present invention. The "front end" in the text refers to the plug end, and the "rear end" refers to the end away from the plug end.

[0046] The present invention provides an optical fiber assembly and a heavy-duty connector, wherein the heavy-duty connector includes a fixed frame (not shown in the figure) and an optical fiber assembly. Since the optical fiber assembly needs to be installed in the fixed frame of the heavy-duty connector, the installation size and maximum external size of the optical fiber assembly are limited. The optical fiber assembly of the present invention adopts a modular design and can be installed in the rectangular installation cavity of the original fixed frame, which is convenient for installation and subsequent maintenance at any time, and can meet the needs of rail transit and other heavy-duty application fields for high-speed signal interconnection. The specific structure of the optical fiber assembly is described in detail below.

[0047] The fiber optic assembly includes a plug and a socket, please refer to Figures 1 to 9 , wherein the plug includes a head shell 2, a head inner shell 3, a fiber contact 6, a cover plate 4, a sealing body 5, an axial spring 9 and a limit plate 8. The head shell 2 is a cubic structure as a whole, and the head inner shell 3 is a cubic structure with different front and rear sizes. Specifically, the head inner shell 3 includes a small cubic segment 3-1 located at the front section and a large cubic segment 3-2 coaxially arranged at the rear of the small cubic segment 3-1. The large cubic segment 3-2 is accommodated in the head shell 2, the small cubic segment 3-1 passes through the head shell 2, and the fiber contact 6 is installed in the head inner shell 3. The socket includes a seat shell 1, a fiber contact 6, a cover plate 4 and a sealing body 5. The seat shell 1 is a cubic structure with different front and rear sizes as a whole. The front section of the seat shell 1 is provided with a square hole 101 that is plugged into the small cubic segment 3-1. The seat shell 1 and the head inner shell 3 are plugged into each other through an adaptive square interface, and the fiber contact 6 is installed in the seat shell 1. On the one hand, the present invention designs the seat outer shell 1 and the head inner shell 3 to be plugged in through a square interface. Compared with the commonly used circular interface plug-in, it can further reduce the space occupied by the optical fiber assembly in the heavy-duty connector, and facilitate the subsequent expansion of the heavy-duty connector. On the other hand, the present invention designs both the head outer shell 2 and the seat outer shell 1 to be a square structure, which can be installed in the rectangular installation cavity of the original fixed frame without adjusting the structure of the fixed frame. The head outer shell 2 and the seat outer shell 1 are made of high-strength metal machined and surface-treated to meet the strength and salt spray requirements of the connector.

[0048] It should be noted that a boss 7 is provided on the outer wall of the head shell 2 and / or the seat shell 1, and a groove that matches the boss 7 is provided on the inner wall of the fixed frame to ensure that the optical fiber assembly can be installed in the fixed frame with floating self-alignment function in the X, Y and Z directions.

[0049] In order to minimize the gap generated when the plug is installed and reduce the cost, the head inner shell 3 is formed by one-piece processing, integrating the functions of a common shell and an insulator into one body. The function is the same as that of a conventional plug, which can not only reduce the number of installation parts, but also the fiber installation hole 12 that can fix the fiber contact 6 is added to the inner cavity of the shell, reducing an installation gap. Please refer to Figure 4 and Figure 7In the present invention, at least one guide hole 301 extending forward and backward is provided at the front of the small cube segment 3-1, and a guide pin 14 matching the guide hole 301 is provided on the rear wall of the square hole 101 in the seat shell 1. The guide hole 301 is matched with the guide pin 14 to achieve guidance when the head seat is docked, ensuring accurate guidance. The product adopts a two-level guiding mechanism of the shell and the guide pin 14 to reduce the matching clearance of the head seat docking, prevent excessive axial deflection, and ensure the centering of the optical fiber.

[0050] In the present invention, please refer to Figure 2 The two adjacent sides of the small cube segment 3-1 are connected by arc segments. There are four arc segments in total, namely arc segment A, arc segment B, arc segment C, and arc segment D. The arcs of the four arc segments are not exactly the same. The arcs of the arc segments are not exactly the same, which has the function of preventing wrong insertion. And one of the arc segments (arc segment A) has a larger arc, which can be used for import guidance. Please refer to Figure 2 and Figure 5 A forward-extending limit key 302 is provided on the annular stop surface formed at the connection position between the small cube segment 3-1 and the large cube segment 3-2, and cooperates with the limit groove 201 on the head outer shell 2 to prevent the head inner shell 3 from deflecting.

[0051] In the present invention, please refer to Figures 1 to 6 , the head shell 2 is provided with an axial spring 9 and a limit plate 8, the rear end of the limit plate 8 is provided with a protrusion 801, and the rear end of the head shell 2 is provided with a groove 202 matching the protrusion 801 for limiting, and the limit plate 8 is fixed to the tail of the head shell 2 by a fastener. The front end of the axial spring 9 is pressed against the head inner shell 3, and the rear end is pressed against the limit plate 8. Preferably, the opposite end faces of the head inner shell 3 and the limit plate 8 are provided with a cylindrical groove 11 for limiting the axial spring 9. The axial spring 9 can produce axial compression, and in the front section of the alignment and guiding process of the plug and the socket, it can offset the assembly and guiding tolerance of the shell, and provide a self-protection function for the optical fiber assembly. When the head inner shell 3 is displaced relative to the head shell 2, the force generated by the compression of the axial spring 9 is applied to the head inner shell 3, so that the plug and the socket are kept in a close state, ensuring that the end faces of the optical fiber contact 6 are reliably connected. The limit plate 8 is used to fix the axial spring 9 to prevent the axial spring 9 from being compressed too much in the axial direction, resulting in failure of the spring function.

[0052] Please refer to Figure 4 and Figure 8, the head inner shell 3 and the seat outer shell 1 are provided with at least one optical fiber installation hole 12 extending in the front-to-back direction from front to back, and a mounting groove 13 connected to the rear end of at least one optical fiber installation hole 12; the optical fiber contact 6 is positioned in the optical fiber installation hole 12 of the head inner shell 3 or the seat outer shell 1 through a top stop positioning structure, and the front end of the optical fiber installation hole 12 is provided with a conical chamfer to guide the optical fiber contact 6. A cover plate 4 is provided in the mounting groove 13 for fixing the top stop positioning structure. Specifically, the top stop positioning structure includes a positioning spring 10 installed in the optical fiber installation hole 12 and a limiting sleeve 16 fixedly installed on the outer wall of the optical fiber contact 6. One end of the positioning spring 10 abuts against the step of the inner wall of the optical fiber installation hole 12, and the other end abuts against the cover plate 4, thereby improving the support strength of the positioning spring 10. The limiting sleeve 16 is an annular structure with a boss as a whole. The positioning spring 10 cooperates with the limiting sleeve 16 to position the optical fiber contact 6. The optical fiber contact 6 is fixed in the optical fiber mounting hole 12 by the positioning spring 10. A spring piece 1001 is arranged on the positioning spring 10. When the optical fiber contact 6 is sent into the correct position of the optical fiber mounting hole 12 by using an embedding tool, the spring piece 1001 on the positioning spring 10 clamps the limiting sleeve 16 to fix the optical fiber contact 6 in the correct position. When the optical fiber contact 6 needs to be removed, the cover plate 4 is first removed from the head inner shell 3 or the seat outer shell 1, and then the removal tool is extended to the positioning spring 10 from the rear end of the head inner shell 3 or the seat outer shell 1. When the removal tool is used to expand the spring piece 1001 on the positioning spring 10, the optical fiber contact 6 can be easily removed from the rear end of the optical fiber mounting hole 12, which greatly improves the maintainability of the connector and has single-point maintainability of the optical cable. It should be noted that the specific structures of the optical fiber contact 6 in the plug and the socket are not the same. The optical fiber contact 6 of the socket contains a pin, and the optical fiber contact 6 of the plug contains a socket. This belongs to the prior art and will not be described in detail in the present invention.

[0053] Preferably, regarding the fixing method of the cover plate 4 and the head inner shell 3 or the seat outer shell 1, positioning grooves 1301 are provided on the four side walls of the installation groove 13 of the head inner shell 3 or the seat outer shell 1, and the sizes of the positioning grooves 1301 are not exactly the same. Positioning blocks 401 that cooperate with the positioning grooves 1301 are provided on the side walls of the cover plate 4. By setting the positioning grooves 1301 and the positioning blocks 401, the cover plate 4 can be positioned, and the positioning grooves 1301 can also be used as a sol groove, so that the cover plate 4 and the head inner shell 3 or the seat outer shell 1 become a uniform medium whole through gluing.

[0054] Preferably, the optical fiber contact 6 can also be a beam expansion optical fiber contact, which has a built-in lens to achieve the effect of beam expansion and focusing, and realize non-contact transmission of optical signals. The optical signal can be expanded by dozens to hundreds of times after beam expansion, and the influence of small pollutants on signal transmission is greatly reduced, ensuring that the signal transmission is still highly reliable in harsh environments.

[0055] As a preferred embodiment of the present invention, the optical fiber assembly also includes a sealing structure. In order to ensure the sealing of the wire outlet part at the tail of the connector and prevent external dust, liquid and harmful gas from invading the inside of the plug or socket, a first-level sealing structure is designed at the tail of the plug or socket, and the first-level sealing structure is a wire sealing body 5 arranged behind the cover plate 4. A plurality of drum-shaped step holes 501 are designed inside the wire sealing body 5, and these drum-shaped step holes 501 can firmly clamp the wires passing through. At the same time, by potting silicone rubber between the wire sealing body 5 at the tail and the head seat shell, the sealing between the cover plate 4 and the outside world can be achieved. For the hole position where the optical fiber contact 6 is not installed, in order to achieve the sealing effect, a special sealing plug is also designed to be inserted into the drum-shaped step hole 501 of the wire sealing body. In order to improve the sealing effect between the optical fiber contacts 6, an interface sealing pad 15 is designed on the plugging surface of the optical fiber contact 6 in the socket, and a conical elastic protrusion 1501 is designed around a single pin. After the head seat is inserted, the conical elastic protrusion 1501 on one side of the pin is pressed together with the end face of the head inner shell 3 in the plug, forming a sealing barrier between the optical fiber contacts 6, so that each pair of mating optical fiber contacts 6 can achieve a sealing effect, thereby improving the environmental resistance of the connector.

[0056] The above is a detailed introduction to an optical fiber assembly and a heavy-duty connector provided by the present invention. The principles and specific implementation methods of the present invention are described in this article using specific examples. The above embodiments are only used to help understand the methods and core ideas of the present invention. It should be pointed out that for ordinary technicians in this field, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention fall within the protection scope of the present invention.

Claims

1. An optical fiber assembly, characterized in that: include: A plug comprises a head outer shell (2) and a head inner shell (3), wherein an optical fiber contact piece (6) is installed in the head inner shell (3), and the head outer shell (2) is in a cubic structure as a whole, with the plug-in end as the front end, and the head inner shell (3) comprises a small cubic section (3-1) located at the front section, and the small cubic section (3-1) extends out of the head outer shell (2); The socket comprises a socket shell (1), the socket shell (1) being of a square structure as a whole, an optical fiber contact piece (6) being installed in the socket shell (1), a front section of the socket shell (1) being provided with a square hole (101) which is plugged into the small square section, and the socket shell (1) and the head inner shell (3) are plugged into each other through a matching square interface.

2. The optical fiber assembly according to claim 1, characterized in that: At least one guide hole (301) extending forward and backward is provided at the front of the small cube segment (3-1), and a guide pin (14) matching the guide hole (301) is provided on the rear wall of the square hole (101).

3. The optical fiber assembly according to claim 1, characterized in that: Two adjacent side surfaces of the small cube segment (3-1) are connected by arc segments, and the curvatures of at least two arc segments are different.

4. The optical fiber assembly according to claim 1, characterized in that: The head inner shell (3) and the seat outer shell (1) are each provided with at least one optical fiber installation hole (12) extending in the front-to-back direction, and an installation groove (13) connected to the rear end of the at least one optical fiber installation hole (12); the optical fiber contact piece (6) is installed in the optical fiber installation hole (12) by means of a top stop positioning structure.

5. The optical fiber assembly according to claim 4, characterized in that: The front end of the optical fiber installation hole (12) is provided with a conical chamfer.

6. The optical fiber assembly according to claim 4, characterized in that: The top stop positioning structure comprises a positioning spring (10) installed in the optical fiber installation hole (12) and a limiting sleeve (16) fixedly installed on the outer wall of the optical fiber contact piece (6); the positioning spring (10) and the limiting sleeve (16) cooperate to position the optical fiber contact piece (6).

7. The optical fiber assembly according to claim 6, characterized in that: A cover plate (4) for fixing a positioning retaining ring (10) is installed in the installation groove (13), a positioning groove (1301) is provided on the side wall of the installation groove (13), and a positioning block (401) matching the positioning groove (1301) is provided on the side wall of the cover plate (4).

8. The optical fiber assembly according to claim 1, characterized in that: An axial spring (9) and a limit plate (8) are provided in the head outer shell (2); the limit plate (8) is fixed to the rear end of the head outer shell (2); the front end of the axial spring (9) presses against the head inner shell (3) and the rear end presses against the limit plate (8).

9. The optical fiber assembly according to claim 8, characterized in that: The head inner shell (3) and the limiting plate (8) are both provided on opposite end surfaces with cylindrical grooves (11) for limiting the axial spring (9).

10. The optical fiber assembly according to claim 8, characterized in that: A protrusion (801) is provided at the rear end of the limiting plate (8), and a groove (202) matching the protrusion (801) is provided at the rear end of the head shell (2).

11. The optical fiber assembly according to claim 1, characterized in that: The small cube segment (3-1) is provided with a limit key (302) extending forward, which cooperates with the limit slot (201) on the head outer shell (2) to prevent the head inner shell (3) from deflecting in the head outer shell (2).

12. The optical fiber assembly according to claim 7, characterized in that: The optical fiber assembly also includes a sealing structure, which includes a first-level sealing structure arranged at the rear of the head inner shell (3) and / or the seat outer shell (1) for sealing the wire, and a second-level sealing structure arranged at the front end of the socket for plugging with the plug-in end of the plug to seal the interface between the two in the plugged state.

13. The optical fiber assembly according to claim 12, characterized in that: The first-level sealing structure comprises a sealing body (5) arranged behind the cover plate (4), and the sealing body (5) is glued and fixed to the cover plate (4).

14. The optical fiber assembly according to claim 12, characterized in that: The second-level sealing structure is an interface sealing pad (15) arranged close to the rear wall of the square hole (101) in the socket, and a conical elastic protrusion (1501) is provided on the front end surface of the interface sealing pad (15) at a position corresponding to the installation of the optical fiber contact piece (6).

15. A heavy-duty connector, characterized in that: The invention comprises a fixing frame and an optical fiber assembly according to any one of claims 1 to 14 installed in a rectangular installation cavity in the fixing frame.

16. A heavy-duty connector according to claim 15, characterized in that: A boss (7) is provided on the outer wall of the head housing (2) and / or the seat housing (1), and a groove that is clearance-matched with the boss (7) is provided on the inner wall of the fixed frame to ensure that the optical fiber assembly can float along the fixed frame.

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