Optical fiber connector, prefabricated optical fiber, adapter, fiber termination box, and optical fiber connection assembly

An optical fiber connector, comprising a main shaft, a connecting piece, and a lock cap. The main shaft comprises a head end and a tail end that is away from the head end. A through hole extending from the head end to the tail end is disposed in the main shaft. The connecting piece is fixedly connected to the head end and partially accommodated in the through hole. The lock cap includes a sealing portion and a connection portion that is connected to a side of the sealing portion. The sealing portion is rotationally connected to an outer side of the head end. The connection portion is located on a side that is of the head end and that is away from the tail end.

TECHNICAL FIELD

This application relates to an optical fiber connector, a prefabricated optical fiber, an adapter, a fiber termination box, and an optical fiber connection assembly.

BACKGROUND

To simplify operations during drop cable layout of a fiber-to-the-home (FTTH) network, industry insiders use an optical fiber pre-connection product to connect a drop cable to a fiber distribution box and a customer terminal box. Both ends of the drop cable of the optical fiber pre-connection product are provided with prefabricated optical fiber connectors, and the fiber distribution box and the customer terminal box are also provided with corresponding prefabricated fiber adapters. During the drop cable layout, it is only required to insert the optical fiber connectors on both ends of the drop cable into the corresponding fiber adapters on the customer terminal box and on the fiber distribution box respectively.

A conventional optical fiber connector and a conventional fiber adapter are locked to each other using a threaded connection structure between the optical fiber connector and the fiber adapter. Such a connection manner requires the optical fiber connector to rotate for a plurality of turns during locking and detaching, and is complex to operate. In addition, the conventional optical fiber connector and the conventional fiber adapter may not be properly or securely locked through manual operation, resulting in poor reliability of the connection between the optical fiber connector and the fiber adapter.

SUMMARY

Embodiments of this application provide an optical fiber connector, a prefabricated optical fiber to which the optical fiber connector is applied, an adapter, a fiber termination box to which the adapter is applied, and an optical fiber connection assembly. The optical fiber connector and the adapter of the optical fiber connection assembly are easy to assemble and disassemble, and a connection between the optical fiber connector and the adapter is highly reliable.

According to a first aspect, an embodiment of this application provides an optical fiber connector, including a main shaft, a connecting piece, and a lock cap. The main shaft includes a head end and a tail end that is away from the head end. A through hole extending from the head end to the tail end is disposed in the main shaft. The connecting piece is fixedly connected to the head end and partially accommodated in the through hole. The lock cap includes a sealing portion and a connection portion that is connected to a side of the sealing portion. The sealing portion is rotationally connected to an outer side of the head end. The connection portion is located on a side that is of the head end and that is away from the tail end. The connection portion is configured to partially accommodate an adapter when the connecting piece is inserted into the adapter. A lock protrusion is disposed on an inner side of the connection portion. The lock protrusion is configured to be snap-fitted to a lock slot of the adapter when the lock cap is rotated by a first angle relative to the adapter. The first angle is less than or equal to 90 degrees (°).

In this embodiment, the lock protrusion is disposed on the lock cap of the optical fiber connector, and the lock protrusion and the lock slot can be snap-fitted to each other after the lock protrusion and the lock slot are rotated relative to each other. Therefore, the optical fiber connector can be connected to the corresponding adapter in a rotary snap-fit lock manner. Assembly and disassembly of the optical fiber sub-assembly and the adapter are simple and time-saving, the connected optical fiber connector and adapter are highly stable and secure, and a signal transmission process between the optical fiber connector and the adapter is reliable.

In an optional embodiment, the main shaft further includes a transition section located between the head end and the tail end. A first limiting surface facing the tail end is disposed on the transition section. The lock cap further includes a limiting portion connected to a side that is of the sealing portion and that is away from the connection portion. A second limiting surface facing the sealing portion is disposed on the limiting portion. The optical fiber connector further includes an elastic part. The elastic part is located between the transition section and the sealing portion, and two ends of the elastic part abut against the first limiting surface and the second limiting surface respectively.

In this embodiment, the elastic part is disposed such that the first limiting surface and the second limiting surface tend to move away from each other, and the lock cap tends to move toward the tail end of the main shaft. Therefore, when the lock cap is connected to an adapter, the lock protrusion can be stably snap-fitted to the lock slot of the adapter, and the connecting piece and the adapter are fastened to each other such that a connection relationship between the optical fiber connector and the adapter is reliable, thereby achieving good shockproof and anti-looseness effects.

In an optional embodiment, the connecting piece includes a connection base and one or more connection terminals. One end of the connection base is inserted into the through hole. The one or more connection terminals are fastened to the other end of the connection base.

In this embodiment, the one or more connection terminals may be mounted on the connection base together such that the optical fiber connector may be applicable to more types of prefabricated optical fibers with different requirements, and applicability of the optical fiber connector is relatively good. When a plurality of connection terminals are mounted on the connection base together, a port density of the optical fiber connector is relatively high.

In an optional embodiment, the connection terminal includes a protective housing and a ferrule mounted in the protective housing. A top end face that is of the protective housing and that is away from the connection base protrudes relative to a top end face that is of the ferrule and that is away from the connection base. In this case, the top end face of the protective housing can protect the ferrule. When the optical fiber connector is connected to an adapter, the top end face of the protective housing is, earlier than the ferrule, inserted into the adapter, to prevent the ferrule from damage due to an inaccurate action of an installation engineer in a blind-mate scenario, thereby lowering a requirement for inserting the optical fiber connector and extending a service life of the optical fiber connector.

In an optional embodiment, the connection base includes a fastening portion and one or more mounting portions located on a side of the fastening portion. The one or more mounting portions are partially inserted into the one or more connection terminals in a one-to-one correspondence manner. The fastening portion and the one or more mounting portions are integrally formed. That is, the connection base is integrally formed. In this case, the one or more connection terminals are fastened to the connection base through insertion.

In this embodiment, the mounting portion is inserted into the connection terminal such that the optical fiber connector implements fastening of the connection terminal to the connection base. Therefore, the connection base can have an integrally formed structure, thereby reducing manufacturing costs and manufacturing difficulty of the connection base. In addition, the connection terminal is fastened to the connection base through insertion. Such an assembly process is more convenient and less difficult.

In an optional embodiment, the connection terminal includes a protective housing and a ferrule mounted in the protective housing. A limiting hole is disposed on the protective housing. A limiting protrusion is disposed on the mounting portion. The mounting portion is partially inserted into the corresponding protective housing, and the limiting protrusion is partially or completely clamped in the limiting hole.

In this embodiment, the connection terminal and the connection base are fastened to each other through a snap-fit connection between the limiting hole and the limiting protrusion such that the connection terminal can be fastened to the connection base through insertion. This connection manner between the connection terminal and the connection base is easy to implement and stable.

In an optional embodiment, an inner surface of the protective housing includes a first locating surface facing the fastening portion. An outer sidewall of the ferrule includes a second locating surface facing away from the fastening portion. The connecting piece further includes an elastic connection part. The elastic connection part is compressed between the ferrule and the mounting portion. An elastic force of the elastic connection part firmly presses the second locating surface against the first locating surface. In this case, the ferrule is fastened relative to the protective housing, and the ferrule is not swaying. This helps ensure connection reliability between the optical fiber connector and an adapter.

In an optional embodiment, an outer diameter of the sealing portion is less than an outer diameter of the connection portion. In this case, an outer circumferential surface of the lock cap has a step-shaped structure, and the lock cap substantially has a step-shaped cylinder structure, thereby meeting a requirement for accommodation capacity of the lock cap (the lock cap is required to accommodate most components of the optical fiber connector), and minimizing a volume of the lock cap. Therefore, the optical fiber connector is more compact, and a risk of interference between the optical fiber connector and an adjacent structure during installation is reduced.

In an optional embodiment, the optical fiber connector further includes a first sealing ring. The first sealing ring is located in the connection portion. The first sealing ring is configured to be compressed between the connection portion and an adapter. In this case, the first sealing ring is configured to seal a connection between the lock cap and another component, to achieve waterproof and dustproof effects such that the optical fiber connector has a longer service life and higher reliability.

In an optional embodiment, a sealing groove wrapping around the through hole is disposed on an outer circumferential side of the main shaft. The optical fiber connector further includes a second sealing ring. The second sealing ring is compressed between a groove wall of the sealing groove and an inner side surface of the sealing portion. In this case, the second sealing ring can prevent external moisture, dust, or the like from entering the lock cap through a gap between the lock cap and the main shaft, thereby improving reliability of the optical fiber connector.

In an optional embodiment, the optical fiber connector further includes a sealing sleeve. One end of the sealing sleeve is sleeved on an outer side of the tail end in a sealing manner. The other end of the sealing sleeve is configured to allow insertion of an optical cable and be connected to the optical cable in a sealing manner. The sealing sleeve is configured to implement a sealed connection between the optical cable and the main shaft, to improve reliability of the optical fiber connector and extend a service life of the optical fiber connector.

In an optional embodiment, the tail end includes a rubber portion close to the head end and a metal portion that is away from the head end. The metal portion is partially located in the rubber portion and is fixedly connected to the rubber portion. The metal portion and the rubber portion may be integrally formed through in-mold decoration. The metal portion and the rubber portion may alternatively form an integrated structure through assembly (for example, a threaded connection or a snap-fit connection).

The sealing sleeve is connected to a part of the metal portion and a part of the rubber portion in a sealing manner. In this case, for the sealing sleeve, the end connected to the tail end of the main shaft is connected to both a part of the metal portion and a part of the rubber portion in a sealing manner. In this case, a connection relationship between the sealing sleeve and the tail end of the main shaft is more stable and reliable.

In an optional embodiment, the optical fiber connector further includes a metal crimp ring. The metal crimp ring is located in the sealing sleeve. One end of the metal crimp ring is sleeved on an outer side of the metal portion. The other end of the metal crimp ring is configured to be sleeved on an outer side of the optical cable, and the end of the metal crimp ring is capable of firmly pressing an aramid yarn of the optical cable against the metal portion.

In this embodiment, the metal crimp ring firmly presses the aramid yarn against the metal portion, thereby improving connection strength between the optical cable and the main shaft, and improving tensile strength of the optical fiber connector.

In an optional embodiment, the optical fiber connector further includes a dust cap and a lanyard. One end of the lanyard is sleeved on an outer side of the main shaft. The other end of the lanyard is connected to the dust cap. A dustproof lock slot is disposed on an end of the dust cap. The end of the dust cap is capable of extending into the connection portion, and the dustproof lock slot is snap-fitted to the lock protrusion.

In this embodiment, when the optical fiber connector is not connected to an adapter, the dust cap may be mounted on one end that is of the lock cap and that is away from a tail ferrule, to be sleeved on an outer side of the connecting piece, thereby achieving waterproof and dustproof effects and protecting the connecting piece. When the optical fiber connector is to be connected to an adapter, the dust cap is detached from the lock cap such that the connecting piece is exposed and can be connected to the adapter through insertion. However, the dust cap is still connected to another structure of the optical fiber connector using the lanyard, to prevent the dust cap from getting lost. The dust cap can be mounted to the lock cap again after the optical fiber connector is detached from the adapter such that the optical fiber connector allows frequent insertion and detachment, thereby improving reliability of the optical fiber connector.

According to a second aspect, an embodiment of this application further provides a prefabricated optical fiber. The prefabricated optical fiber includes an optical cable and the optical fiber connector according to any one of the foregoing embodiments. The optical cable extends into the through hole and is connected to the connecting piece.

In this embodiment, the optical fiber connector of the prefabricated optical fiber can be connected to an adapter of a fiber termination box in a rotary snap-fit lock manner such that assembly is less difficult and time-saving. Therefore, the prefabricated optical fiber can be better applied to an FTTH network. This helps simplify installation during cable layout of an FTTH network and shorten onsite work duration.

According to a third aspect, an embodiment of this application further provides an adapter. The adapter includes an adapter body. The adapter body includes an input end and an output end that is away from the input end. A penetration hole extending from the input end to the output end is disposed in the adapter body. The penetration hole is configured to accommodate a part of a connecting piece of an optical fiber connector when the input end is inserted into a lock cap of the optical fiber connector. A lock slot is disposed on an outer sidewall of the input end. The lock slot extends a second angle in a circumferential direction of the input end. The second angle is less than or equal to 90°. The lock slot is configured to accommodate a lock protrusion on an inner side of the lock cap and be snap-fitted to the lock protrusion.

In this embodiment, the lock slot is disposed on the adapter and the lock slot can be snap-fitted to the lock protrusion on the lock cap of the optical fiber connector. Therefore, the adapter can be connected to the optical fiber connector in a rotary snap-fit lock manner. An angle of rotation of the lock cap of the optical fiber connector relative to the adapter body is limited by a structure size of the lock slot such that the angle of rotation of the lock cap relative to the adapter body is less than or equal to the second angle. The second angle is less than or equal to 90°. Therefore, assembly and disassembly of the adapter and the optical fiber connector are simple, less difficult, and time-saving, and a connection relationship between the connected adapter and optical fiber connector is stable, reliable, and secure.

In an optional embodiment, the adapter further includes a protective cap and a connection lanyard. One end of the connection lanyard is sleeved on an outer side of the adapter body. The other end of the connection lanyard is connected to the protective cap. A protective lock protrusion is disposed on an inner side of an end of the protective cap. The end of the protective cap can be sleeved on an outer sidewall of the input end, and the protective lock protrusion is snap-fitted to the lock slot.

In this embodiment, the protective cap is connected to the adapter body in a rotary snap-fit lock manner. A structure of the lock slot is designed such that an angle of rotation of the protective cap relative to the adapter body is less than or equal to a second angle, where the second angle is less than or equal to 90°. Therefore, assembly and disassembly of the protective cap are simple and time-saving, and a snap-fit connection between the protective cap and the adapter body is highly stable and secure. In this way, the protective cap can effectively protect the adapter body from water, dust, and the like, thereby helping improve reliability of the adapter. The protective cap is connected to the adapter body using the connection lanyard such that the protective cap is difficult to be detached, thereby improving the reliability of the adapter.

According to a fourth aspect, an embodiment of this application further provides a fiber termination box. The fiber termination box includes a box body and the adapter according to any one of the foregoing embodiments, where the adapter is mounted on the box body.

In this embodiment, the adapter of the fiber termination box can be connected to an optical fiber connector in a rotary snap-fit lock manner such that assembly of the adapter and the optical fiber connector is less difficult and time-saving. Therefore, the fiber termination box can be better connected to a prefabricated optical cable that has the optical fiber connector. This helps simplify installation during cable layout of an FTTH network and shorten onsite work duration.

According to a fifth aspect, an embodiment of this application further provides an optical fiber connection assembly. The optical fiber connection assembly includes an optical fiber connector and an adapter. The optical fiber connection assembly may be applied, in an FTTH network, to a connection between a fiber distribution box and a prefabricated optical fiber, and a connection between a prefabricated optical fiber and a customer terminal box.

The optical fiber connector includes a main shaft, a connecting piece, and a lock cap. The main shaft includes a head end and a tail end that is away from the head end. A through hole extending from the head end to the tail end is disposed in the main shaft. The connecting piece is fixedly connected to the head end and partially accommodated in the through hole. The lock cap includes a sealing portion and a connection portion that is connected to a side of the sealing portion. The sealing portion is rotationally connected to an outer side of the head end. The connection portion is located on a side that is of the head end and that is away from the tail end. A lock protrusion is disposed on an inner side of the connection portion.

A body of the adapter includes an input end and an output end that is away from the input end. A penetration hole extending from the input end to the output end is disposed in the adapter body. A lock slot is disposed on an outer sidewall of the input end. The lock slot extends a second angle in a circumferential direction of the input end. The second angle is less than or equal to 90°.

When the connecting piece is partially inserted into the penetration hole, the connection portion accommodates a part of the input end and the lock protrusion is located in the lock slot. The lock protrusion is snap-fitted to the lock slot when the lock cap is rotated by a first angle relative to the adapter body. The first angle is less than or equal to the second angle.

In this embodiment, the lock protrusion is disposed on the lock cap of the optical fiber connector, and the lock protrusion and the lock slot can be snap-fitted to each other after the lock protrusion and the lock slot are rotated relative to each other. Therefore, the optical fiber connector can be connected to the adapter in a rotary snap-fit lock manner. An angle of rotation of the lock cap of the optical fiber connector relative to the adapter body is limited by a structure size of the lock slot such that the first angle of rotation of the lock cap relative to the adapter body is less than or equal to the second angle. The second angle is less than or equal to 90°. Therefore, the optical fiber connector and the adapter are simple and time-saving, the connected optical fiber connector and adapter are stably and securely connected, and a signal transmission process between the optical fiber connector and the adapter is reliable.

In an optional embodiment, the main shaft further includes a transition section located between the head end and the tail end. A first limiting surface facing the tail end is disposed on the transition section. The lock cap further includes a limiting portion connected to a side that is of the sealing portion and that is away from the connection portion. A second limiting surface facing the sealing portion is disposed on the limiting portion. The optical fiber connector further includes an elastic part. The elastic part is located between the transition section and the sealing portion, and two ends of the elastic part abut against the first limiting surface and the second limiting surface respectively.

In this embodiment, the elastic part is disposed on the optical fiber connector such that the first limiting surface and the second limiting surface tend to move away from each other, and the lock cap tends to move toward the tail end of the main shaft. Therefore, when the lock cap is connected to an adapter, the lock protrusion can be stably snap-fitted to the lock slot of the adapter, and the connecting piece and the adapter are fastened to each other such that a connection relationship between the optical fiber connector and the adapter is reliable, thereby achieving good shockproof and anti-looseness effects.

In an optional embodiment, the connecting piece includes a connection base and one or more connection terminals. One end of the connection base is inserted into the through hole. One end of the one or more connection terminals is fastened to the other end of the connection base. The other end of the one or more connection terminals is inserted into the penetration hole.

In this embodiment, the one or more connection terminals may be mounted on the connection base together such that the optical fiber connector may be applicable to more types of prefabricated optical fibers with different requirements, and applicability of the optical fiber connector is relatively good. When a plurality of connection terminals are mounted on the connection base together, a port density of the optical fiber connector is relatively high.

No conventional elastic arm is disposed on the connection terminal of the optical fiber connector in this embodiment. A lock requirement between the optical fiber connector and the adapter is met using a rotary snap-fit lock structure such that a conventional two-step assembly/disassembly process (elastic arm assembly/disassembly and protective cover assembly/disassembly) is simplified into a one-step assembly/disassembly process, thereby further reducing difficulty of and a time for assembly and disassembly of the optical fiber connector and the adapter. In addition, no elastic arm structure is disposed on the connection terminal such that a volume of the connection terminal is reduced. Therefore, a port density can be increased without increasing a volume of the optical fiber connector.

In an optional embodiment, the connection terminal includes a protective housing and a ferrule mounted in the protective housing. A top end face that is of the protective housing and that is away from the connection base protrudes relative to a top end face that is of the ferrule and that is away from the connection base. In this case, the top end face of the protective housing can protect the ferrule. When the optical fiber connector is connected to an adapter, the top end face of the protective housing is, earlier than the ferrule, inserted into the adapter, to prevent the ferrule from damage due to an inaccurate action of an installation engineer in a blind-mate scenario, thereby lowering a requirement for inserting the optical fiber connector and extending a service life of the optical fiber connector.

In an optional embodiment, the connection base includes a fastening portion and one or more mounting portions located on a side of the fastening portion. The one or more mounting portions are partially inserted into the one or more connection terminals in a one-to-one correspondence manner. The fastening portion and the one or more mounting portions are integrally formed. That is, the connection base is integrally formed. In this case, the one or more connection terminals are fastened to the connection base through insertion.

In this embodiment, the mounting portion is inserted into the connection terminal such that the optical fiber connector implements fastening of the connection terminal to the connection base. Therefore, the connection base can have an integrally formed structure, thereby reducing manufacturing costs and manufacturing difficulty of the connection base. In addition, the connection terminal is fastened to the connection base through insertion. Such an assembly process is more convenient and less difficult.

In an optional embodiment, the connection terminal includes a protective housing and a ferrule mounted in the protective housing. A limiting hole is disposed on the protective housing. A limiting protrusion is disposed on the mounting portion. The mounting portion is partially inserted into the corresponding protective housing, and the limiting protrusion is partially or completely clamped in the limiting hole.

In this embodiment, the connection terminal and the connection base are fastened to each other through a snap-fit connection between the limiting hole and the limiting protrusion such that the connection terminal can be fastened to the connection base through insertion. This connection manner between the connection terminal and the connection base is easy to implement and stable.

In an optional embodiment, an inner surface of the protective housing includes a first locating surface facing the fastening portion. An outer sidewall of the ferrule includes a second locating surface facing away from the fastening portion. The connecting piece further includes an elastic connection part. The elastic connection part is compressed between the ferrule and the mounting portion. An elastic force of the elastic connection part firmly presses the second locating surface against the first locating surface. In this case, the ferrule is fastened relative to the protective housing, and the ferrule is not swaying. This helps ensure connection reliability between the optical fiber connector and an adapter.

In an optional embodiment, an outer diameter of the sealing portion is less than an outer diameter of the connection portion. In this case, an outer circumferential surface of the lock cap has a step-shaped structure, and the lock cap substantially has a step-shaped cylinder structure, thereby meeting a requirement for accommodation capacity of the lock cap (the lock cap is required to accommodate most components of the optical fiber connector), and minimizing a volume of the lock cap. Therefore, the optical fiber connector is more compact, and a risk of interference between the optical fiber connector and an adjacent structure during installation is reduced.

In an optional embodiment, the optical fiber connector further includes a first sealing ring. The first sealing ring is located in the connection portion. The first sealing ring is compressed between the connection portion and an adapter. In this case, the first sealing ring is configured to seal a connection between the lock cap and another component, to achieve waterproof and dustproof effects such that the optical fiber connector has a longer service life and higher reliability.

In an optional embodiment, a sealing groove wrapping around the through hole is disposed on an outer circumferential side of the main shaft. The optical fiber connector further includes a second sealing ring. The second sealing ring is compressed between a groove wall of the sealing groove and an inner side surface of the sealing portion. In this case, the second sealing ring can prevent external moisture, dust, or the like from entering the lock cap through a gap between the lock cap and the main shaft, thereby improving reliability of the optical fiber connector.

In an optional embodiment, the optical fiber connector further includes a sealing sleeve. One end of the sealing sleeve is sleeved on an outer side of the tail end in a sealing manner. The other end of the sealing sleeve is configured to allow insertion of an optical cable and be connected to the optical cable in a sealing manner. The sealing sleeve is configured to implement a sealed connection between the optical cable and the main shaft, to improve reliability of the optical fiber connector and extend a service life of the optical fiber connector.

In an optional embodiment, the tail end includes a rubber portion close to the head end and a metal portion that is away from the head end. The metal portion is partially located in the rubber portion and is fixedly connected to the rubber portion. The metal portion and the rubber portion may be integrally formed through in-mold decoration. The metal portion and the rubber portion may alternatively form an integrated structure through assembly (for example, a threaded connection or a snap-fit connection). In this case, for the sealing sleeve, the end connected to the tail end of the main shaft is connected to both a part of the metal portion and a part of the rubber portion in a sealing manner.

The sealing sleeve is connected to a part of the metal portion and a part of the rubber portion in a sealing manner. In this case, a connection relationship between the sealing sleeve and the tail end of the main shaft is more stable and reliable.

In an optional embodiment, the optical fiber connector further includes a metal crimp ring. The metal crimp ring is located in the sealing sleeve. One end of the metal crimp ring is sleeved on an outer side of the metal portion. The other end of the metal crimp ring is configured to be sleeved on an outer side of the optical cable, and the end of the metal crimp ring is capable of firmly pressing an aramid yarn of the optical cable against the metal portion.

In this embodiment, the metal crimp ring firmly presses the aramid yarn against the metal portion, thereby improving connection strength between the optical cable and the main shaft, and improving tensile strength of the optical fiber connector.

DESCRIPTION OF EMBODIMENTS

The following describes the embodiments of this application with reference to the accompanying drawings in the embodiments of this application.

FIG. 1is a schematic diagram of a structure of an FTTH network100according to an embodiment of this application.

The FTTH network100includes a fiber distribution box10, a prefabricated optical fiber20, and a customer terminal box30. The fiber distribution box10and the customer terminal box30are both fiber termination boxes. The fiber distribution box10(also referred to as a fiber access terminal) is an interface device used outdoors, in a building passage, or indoors to connect a feeder optical cable and a distribution optical cable (hereinafter referred to as an optical cable). The fiber distribution box10includes a box body101and an adapter1(also referred to as a fiber adapter) mounted on the box body101. The fiber distribution box10can be connected to a plurality of customer terminal boxes30using a plurality of prefabricated optical fibers20. This embodiment shown inFIG. 1illustrates one prefabricated optical fiber20and one customer terminal box30. The prefabricated optical fiber20includes an optical cable2and optical fiber connectors3. One optical fiber connector3is mounted on each end of the optical cable2. The customer terminal box30includes a box body301and an adapter1mounted on the box body301. The two optical fiber connectors3of the prefabricated optical fiber20are connected to the adapter1of the fiber distribution box10and the adapter1of the customer terminal box30respectively.

In this embodiment, the prefabricated optical fiber20is used in the FTTH network100. During cable layout of the prefabricated optical fiber20, it is only required to insert the two optical fiber connectors3of the prefabricated optical fiber20into the adapter1of the fiber distribution box10and the adapter1of the customer terminal box30respectively such that an installation process is completed. This greatly simplifies installation and shortens onsite work duration.

Referring toFIG. 1andFIG. 2,FIG. 2is a schematic diagram of a structure of an optical fiber connection assembly200according to an embodiment of this application.

The optical fiber connection assembly200includes the optical fiber connector3and the adapter1. A connection between the optical fiber connector3and the adapter1is a detachable connection. The optical fiber connection assembly200may be applied, in the FTTH network100, to a connection between the fiber distribution box10and the prefabricated optical fiber20, and a connection between the prefabricated optical fiber20and the customer terminal box30. A connecting piece31is disposed on one end of the optical fiber connector3. The optical cable2is inserted into the optical fiber connector3from the other end of the optical fiber connector3and is connected to the connecting piece31. When the connecting piece31is inserted into the adapter1, an optical signal can be transmitted between the adapter1and the optical cable2.

The adapter1includes a lock nut11, a connection lanyard12, a ceramic sleeve13, an adapter body14, a sealing ring15, and a protective cap16.

The adapter body14includes an input end141and an output end142that is away from the input end141. A penetration hole143extending from the input end141to the output end142is disposed in the adapter body14. An optical signal can be input from the input end141of the adapter body14and output from the output end142through the penetration hole143. When the adapter1is connected to the optical fiber connector3, the penetration hole143accommodates a part of the connecting piece31of the optical fiber connector3. A shape of the penetration hole143is adapted to a shape of the connecting piece31accommodated by the penetration hole143. There may be one or more penetration holes143. When there are a plurality of penetration holes143, the plurality of penetration holes143are disposed apart from each other. The ceramic sleeve13is disposed in each penetration hole143. The ceramic sleeve13is configured to abut against a part of the connecting piece31of the optical fiber connector3to transmit an optical signal.

Optionally, a lock slot1412is disposed on an outer sidewall1411of the input end141. The lock slot1412extends a second angle in a circumferential direction of the input end141, and the second angle is less than or equal to 90°. The outer sidewall1411of the input end141is a cylindrical surface. The circumferential direction of the input end141is a direction perpendicular to and around a central axis of the outer sidewall1411of the input end141. The second angle is a central angle of the lock slot1412. The second angle may be an angle from 30° to 90°, such as 30°, 45°, 60°, 75°, or 90°. The lock slot1412includes a slide-in area1413, a slide area1414, and a snap-fit area1415that are sequentially connected. The slide area1414and the snap-fit area1415extend in the circumferential direction of the input end141. The slide-in area1413connects the slide area1414to an end face of the input end141. A snap-fit surface1416facing away from the slide-in area1413is disposed on the snap-fit area1415. For example, a direction from the slide area1414to the snap-fit area1415is a slide-in direction, and an orientation of the snap-fit surface1416is opposite to the slide-in direction.

Further, there may be one, two, three or more than three lock slots1412. This embodiment is described using an example in which there are two lock slots1412. The two lock slots1412are disposed facing away from each other. In addition, the two lock slots1412are centrosymmetrically distributed. In an embodiment, when rotated by 180° around the central axis of the outer sidewall1411of the input end141, one lock slot1412overlaps the other lock slot1412. A quantity of the lock slots1412may be designed based on the second angle, provided that a plurality of lock slots1412are designed to be spaced apart from each other. For example, when the second angle is less than 60°, there may be three lock slots1412.

Optionally, the adapter body14further includes a stop flange144located between the input end141and the output end142. An alignment arrow mark1441is disposed on a side that is of the stop flange144and that faces the input end141. The alignment arrow mark1441is configured to indicate a state of connection/disconnection between another component and the adapter body14.

Optionally, a threaded connection portion1422is disposed on an outer sidewall1421of the output end142. The lock nut11is screwed to the threaded connection portion1422. The lock nut11is configured to be connected to a box body of a fiber termination box (refer to101or301inFIG. 1). In another embodiment, the lock nut11may alternatively be a connection component configured to implement another connection manner, and the threaded connection portion1422is another structure corresponding to the connection component. The other connection manner includes but is not limited to a snap-fit connection, a mortise and tenon connection, an interference connection, or an elastic connection.

Referring toFIG. 3andFIG. 4,FIG. 4is a schematic diagram of a structure of the protective cap16shown inFIG. 3.

Optionally, one end121of the connection lanyard12is sleeved on an outer side of the adapter body14, and the other end122of the connection lanyard12is connected to the protective cap16. In an embodiment, the end121of the connection lanyard12is sleeved on an outer side of the output end142, and is located between the stop flange144and the lock nut11. The protective cap16includes a connection cap portion161and a holding part322. A top of the connection cap portion161is open. The holding part162is located on a bottom of the connection cap portion161. A connection groove163is disposed between the connection cap portion161and the holding part162. The connection groove163is a continuous annular groove. The end122that is of the connection lanyard12and that is away from the adapter body14is located in the connection groove163, to connect the protective cap16.

Optionally, a protective lock protrusion164is disposed on an inner side of an end of the protective cap16. The end of the protective cap16can be sleeved on an outer sidewall of the input end141, and the protective lock protrusion164is snap-fitted to the lock slot1412. In an embodiment, the protective lock protrusion164is disposed on an inner side of the connection cap portion161. When the protective cap16is connected to the adapter body14, the connection cap portion161is sleeved on the outer sidewall of the input end141, that is, the input end141is inserted into the connection cap portion161. The protective lock protrusion164slides from the slide-in area1413to the lock slot1412. When the protective cap16is rotated relative to the adapter body14, the protective lock protrusion164slides through the slide area1414to the snap-fit area1415, and then is snap-fitted to the snap-fit surface1416of the snap-fit area1415. A snap-fit matching surface matching the snap-fit surface1416may be further disposed on the protective lock protrusion164, to improve snap-fit stability between the protective lock protrusion164and the adapter body14.

In this embodiment, the protective cap16is connected to the adapter body14in a rotary snap-fit lock manner. A structure of the lock slot1412is designed such that an angle of rotation of the protective cap16relative to the adapter body14is less than or equal to the second angle, where the second angle is less than or equal to 90°. Therefore, assembly and disassembly of the protective cap16are simple and time-saving, and a snap-fit connection between the protective cap16and the adapter body14is highly stable and secure. In this way, the protective cap16can effectively protect the adapter body14from water, dust, and the like, thereby helping improve reliability of the adapter1. The protective cap16is connected to the adapter body14using the connection lanyard12such that the protective cap16is difficult to be detached, thereby improving the reliability of the adapter1.

An indicative arrow sign1612may be disposed on an outer sidewall of the connection cap portion161, to guide a user to execute assembly and disassembly actions. An arrow sign1417used to indicate an insertion direction is disposed on the outer sidewall1411of the input end141. When the indicative arrow sign1612is aligned with the arrow sign1417on the outer sidewall1411of the input end141, the protective cap16can be aligned with the adapter body14, to be quickly mounted on the adapter body14. When the indicative arrow sign1612is used with the alignment arrow mark1441on the stop flange144, a connection/disconnection state of the protective cap16and the adapter body14can be indicated.

Optionally, a sealing groove1418is disposed on the outer sidewall1411of the input end141. The sealing groove1418is an annular groove. The sealing groove1418is located on a side that is of the lock slot1412and that is close to the output end142. The sealing ring15is mounted in the sealing groove1418. When the protective cap16is connected to the adapter body14, the sealing ring15is firmly pressed between a groove wall of the sealing groove1418and an inner sidewall of the connection cap portion161. In this case, the sealing ring15seals a gap between the input end141and the connection cap portion161, to prevent external moisture, dust, and the like from entering the penetration hole143, thereby extending a service life of the adapter1.

Referring toFIG. 2,FIG. 5andFIG. 6,FIG. 5is a schematic diagram of a structure of a prefabricated optical fiber20according to an embodiment of this application, andFIG. 6is a schematic exploded-view diagram of the prefabricated optical fiber20shown inFIG. 5. An optical fiber connector3of the prefabricated optical fiber20shown inFIG. 5corresponds to the optical fiber connector3shown inFIG. 2. A part of a structure of a lanyard37of the optical fiber connector3is not shown inFIG. 5andFIG. 6.

The prefabricated optical fiber20includes an optical cable2and the optical fiber connector3. The optical fiber connector3includes a dust cap32, a first sealing ring33, a connecting piece31, a main shaft34, an elastic part35, a second sealing ring36, the lanyard37, a snap ring38, an adhesive container310, a lock cap39, a tail ferrule320, a metal crimp ring330, and a sealing sleeve340.

The lock cap39, one end371of the lanyard37, and the tail ferrule320are arranged in an axial direction (parallel to a line A-A inFIG. 5) of the optical fiber connector3. The lock cap39is a hollow cylinder (which may also be referred to as a socket, that is, the cylinder has an inner through-hole structure that penetrates from one end of the cylinder to the other end). The tail ferrule320is a hollow cylinder. An inner through-hole395of the lock cap39is connected to an inner through-hole of the tail ferrule320. The connecting piece31is partially located in the inner through-hole395of the lock cap39, and the connecting piece31partially protrudes relative to an end that is of the lock cap39and that is away from the tail ferrule320. The optical cable2of the prefabricated optical fiber20can extend from one end that is of the tail ferrule320and that is away from the lock cap39sequentially into the inner through-hole of the tail ferrule320and the inner through-hole395of the lock cap39, to be connected to the connecting piece31. Other structures of the optical fiber connector3are located in the inner through-hole395of the lock cap39and the inner through-hole of the tail ferrule320.

The dust cap32is connected to the other end372of the lanyard37. The lanyard37is bendable. As shown inFIG. 5, when the optical fiber connector3is not connected to an adapter1, the dust cap32may be mounted on one end that is of the lock cap39and that is away from the tail ferrule320, to be sleeved on an outer side of the connecting piece31, thereby achieving waterproof and dustproof effects and protecting the connecting piece31. As shown inFIG. 2, when the optical fiber connector3is to be connected to the adapter1, the dust cap32is detached from the lock cap39such that the connecting piece31is exposed and can be connected to the adapter1through insertion. However, the dust cap32is still connected to another structure of the optical fiber connector3using the lanyard37, to prevent the dust cap32from getting lost. The dust cap32can be mounted to the lock cap39again after the optical fiber connector3is detached from the adapter1such that the optical fiber connector3allows frequent insertion and detachment, thereby improving reliability of the optical fiber connector3.

Referring toFIG. 6toFIG. 8,FIG. 7is a schematic diagram of a three-dimensional structure of the main shaft34shown inFIG. 6, andFIG. 8is a schematic diagram of an internal structure of the main shaft34shown inFIG. 7.

The main shaft34includes a head end341and a tail end342that is away from the head end341. The main shaft34further includes a transition section343located between the head end341and the tail end342. The head end341, the transition section343, and the tail end342are sequentially arranged. The main shaft34is a hollow cylinder. A through hole344extending from the head end341to the tail end342is disposed in the main shaft34. The through hole344is an inner through-hole of the main shaft34. In this embodiment, an inner diameter of the head end341is greater than an inner diameter of the transition section343. The inner diameter of the transition section343is greater than an inner diameter of the tail end342. The through hole344is a hole with varying diameters. The main shaft34is substantially a step-shaped hollow circular cylinder. In another embodiment, the through hole344may alternatively be a through-hole in another shape.

Two lugs345are disposed on a top that is of the head end341and that is away from the transition section343. The two lugs345are disposed opposite to each other. A limiting block3451is disposed on a top that is of the lug345and that is away from the transition section343. The two limiting blocks3451of the two lugs345are bent towards each other. A first locating hole3452is disposed on one lug345. A limiting bump3412and a limiting flange3413are further disposed on an outer sidewall3411of the head end341. The limiting bump3412and the limiting flange3413are disposed facing away from each other. The limiting bump3412and the limiting flange3413may be disposed close to the two lugs345respectively. An insertion slot3414is further disposed on the head end341. The insertion slot3414connects the through hole344to an outer side of the main shaft34. The insertion slot3414extends to the top of the head end341.

A sealing groove346wrapping around the through hole344is disposed on an outer circumferential side of the main shaft34. The sealing groove346is a continuous annular groove. In this embodiment, the sealing groove346is partially located on the head end341and partially located on the transition section343. In another embodiment, the sealing groove346may alternatively be completely located on the head end341, or completely located on the transition section343.

A first limiting surface3431facing the tail end342is disposed on the transition section343. The first limiting surface3431is located on a side that is of the sealing groove346and that is close to the tail end342. The first limiting surface3431is located on an outer sidewall of the transition section343.

The tail end342includes a rubber portion3421close to the head end341and a metal portion3422that is away from the head end341. The metal portion3422is partially located in the rubber portion3421and is fixedly connected to the rubber portion3421. The metal portion3422and the rubber portion3421may be integrally formed through in-mold decoration (in-mold decoration, IMD). The metal portion3422and the rubber portion3421may alternatively form an integrated structure through assembly (for example, a threaded connection or a snap-fit connection).

A limiting groove3423wrapping around the through hole344is further disposed on an outer circumferential side of the tail end342. The limiting groove3423is located on the rubber portion3421. The limiting groove3423is a continuous annular groove.

Referring toFIG. 6andFIG. 9AtoFIG. 11,FIG. 9Ais a schematic diagram of a structure of the connecting piece31shown inFIG. 6,FIG. 9Bis a schematic diagram of an assembly structure of the connecting piece31shown inFIG. 9A,FIG. 10is a schematic diagram of an internal structure of the connecting piece31shown inFIG. 9A, andFIG. 11is a schematic diagram of an internal structure of an assembled connecting piece31shown inFIG. 10. This embodiment is described using an example in which the connecting piece31is a lucent connector (LC). In another embodiment, the connecting piece31may alternatively be a square connector (SC), a miniature unit coupling (MU) connector, or a multi-fiber push on (MPO) connector.

The connecting piece31includes a connection base311and one or more connection terminals312. The one or more connection terminals312are mounted on the connection base311. The connecting piece31further includes an elastic connection part313. A quantity of elastic connection parts313is the same as a quantity of the connection terminals312. This embodiment is described using an example in which there are two connection terminals312and also two elastic connection parts313.

In this embodiment, the one or more connection terminals312may be mounted on the connection base311together such that the optical fiber connector3may be applicable to more types of prefabricated optical fibers20with different requirements, and applicability of the optical fiber connector3is relatively good. When a plurality of connection terminals312are mounted on the connection base311together, a port density of the optical fiber connector3is relatively high.

The connection base311includes a fastening portion3111and one or more mounting portions3112located on a side of the fastening portion3111. The fastening portion3111and the one or more mounting portions3112are integrally formed. That is, the connection base311is integrally formed. A quantity of the mounting portions3112is the same as a quantity of the connection terminals312. When there are a plurality of mounting portions3112, the plurality of mounting portions3112are located on one side of the fastening portion3111. The one or more mounting portions3112are partially inserted into the one or more connection terminals312in a one-to-one correspondence manner. In this case, the one or more connection terminals312are fastened to the connection base311through insertion.

In this embodiment, the mounting portion3112is inserted into the connection terminal312such that the optical fiber connector3implements fastening of the connection terminal312to the connection base311. Therefore, the connection base311can have an integrally formed structure, thereby reducing manufacturing costs and manufacturing difficulty of the connection base311. In addition, the connection terminal312is fastened to the connection base311through insertion. Such an assembly process is more convenient and less difficult.

Optionally, a connectivity structure3113is formed in the fastening portion3111. A through-hole3114is formed in each mounting portion3112. As shown inFIG. 10, the connectivity structure3113includes one inlet and two outlets that are connected to the inlet. Two through-holes3114of two mounting portions3112are connected to the two outlets respectively. In this case, a cable wire21of the optical cable2(refer toFIG. 6) may extend into the through-hole3114of the mounting portion3112through the connectivity structure3113of the fastening portion3111.

Optionally, a locating plane31112facing the one or more mounting portions3112is disposed on the fastening portion3111. When the connection base311of the connecting piece31is mounted to the main shaft34(refer toFIG. 7), the two limiting blocks3451on the two lugs345of the head end341of the main shaft34are snap-fitted to the locating plane31112such that the connecting piece31is fastened relative to the main shaft34, thereby preventing the connecting piece31from detaching from the main shaft34.

Optionally, an insertion block3115is formed on an outer sidewall of the fastening portion3111. A limiting plane3116facing away from the one or more mounting portions3112is further disposed on the fastening portion3111. The limiting plane3116is a part of the outer sidewall of the fastening portion3111. A second locating hole31114is further disposed on an outer circumferential side of the fastening portion3111. A fastening end face31113facing the one or more mounting portions3112is disposed on the fastening portion3111. The one or more mounting portions3112extend from the fastening end face31113in a direction away from the fastening portion3111.

A mounting bottom3117and a mounting top3118are disposed on each mounting portion3112. The mounting bottom3117is fastened to the fastening end face31113. The mounting top3118is connected to a top end face that is of the mounting bottom3117and that is away from the fastening end face31113. A limiting protrusion3119is disposed on the mounting portion3112. For example, two limiting protrusions3119are disposed facing away from each other on the mounting top3118. A locating block31110between the two limiting protrusions3119is further disposed on the mounting portion3112. The second locating hole31114and the two limiting protrusions3119are all located on an outer sidewall of the mounting top3118. Projection of the outer sidewall of the mounting top3118on the top end face of the mounting bottom3117falls within a scope of the top end face. An abutting face31111facing away from the fastening portion3111is disposed on an inner side of each mounting portion3112. The abutting face31111is an annular surface disposed around an inner through-hole of the mounting portion3112.

Optionally, each connection terminal312includes a protective housing3121and a ferrule3122mounted in the protective housing3121. The protective housing3121is substantially a hollow square cylinder. A limiting hole3123is disposed on the protective housing3121. For example, two limiting holes3123opposite to each other are disposed on the protective housing3121. The limiting hole3123is connected to an inner through-hole of the protective housing3121. During assembly, the mounting portion3112is partially inserted into the corresponding protective housing3121, and the limiting protrusion3119is partially or completely clamped into the limiting hole3123. A fitting structure between the limiting protrusion3119and the limiting hole3123can fasten the connection terminal312relative to the connection base311.

In this embodiment, the connection terminal312and the connection base311are fastened to each other through a snap-fit connection between the limiting hole3123and the limiting protrusion3119such that the connection terminal312can be fastened to the connection base311through insertion. This connection manner is easy to implement and stable.

A locating slot3124between the two limiting holes3123is further disposed on the protective housing3121. The two limiting holes3123and the locating slot3124are located on three sidewalls of the protective housing3121respectively. The locating slot3124extends to a bottom end face that is of the protective housing3121and that faces the fastening portion3111. The locating slot3124is configured to accommodate the locating block31110. During an insertion connection between the protective housing3121and the mounting portion3112, the locating block31110is fitted to the locating slot3124such that the protective housing3121and the mounting portion3112are located. Therefore, insertion of the protective housing3121and the mounting portion3112is smoother.

Optionally, an inner surface of the protective housing3121includes a first locating surface3125facing the fastening portion3111. The inner surface is a hole wall of the inner through-hole of the protective housing3121. The first locating surface3125faces a bottom end face of the protective housing3121. The ferrule3122is of a hollow cylinder structure. The ferrule3122has a bottom close to the fastening portion3111and a top away from the fastening portion3111. An outer sidewall of the ferrule3122includes a second locating surface3126facing away from the fastening portion3111. The second locating surface3126faces a top of the ferrule3122. The outer sidewall of the ferrule3122further includes an abutting face3127facing the fastening portion3111. The abutting face3127and the second locating surface3126are disposed facing away from each other.

The elastic connection part313is compressed between the ferrule3122and the mounting portion3112. An elastic force of the elastic connection part313firmly presses the second locating surface3126against the first locating surface3125. In an embodiment, one end of the elastic connection part313is located between the ferrule3122and a body of the protective housing3121, and abuts against the abutting face3127of the ferrule3122. The other end of the elastic connection part313is located in the mounting portion3112and abuts against the abutting face31111of the mounting portion3112. In this case, the ferrule3122is fastened relative to the protective housing3121, and the ferrule3122is not swaying. This helps ensure connection reliability between the optical fiber connector3and the adapter1.

Optionally, a top end face3128that is of the protective housing3121and that is away from the connection base311protrudes relative to a top end face3129that is of the ferrule3122and that is away from the connection base311. In this case, the top end face3128of the protective housing3121can protect the ferrule3122. When the optical fiber connector3is connected to the adapter1, the top end face3128of the protective housing3121is, earlier than the ferrule3122, inserted into the adapter1, to prevent the ferrule3122from damage due to an inaccurate action of an installation engineer in a blind-mate scenario, thereby lowering a requirement for inserting the optical fiber connector3and extending a service life of the optical fiber connector3.

In this embodiment, one or more protective protrusions31210are disposed on a top of the protective housing3121. An end face that is of the one or more protective protrusions31210and that is away from the connection base is the top end face3128of the protective housing3121. For example, two protective protrusions31210opposite to each other are further disposed on the top of the protective housing3121. The two protective protrusions31210are located on two sides of the inner through-hole of the protective housing3121respectively. The two protective protrusions31210are respectively connected to the two sidewalls that are of the protective housing3121and that face away from each other.

Referring toFIG. 8,FIG. 11andFIG. 12,FIG. 12is a sectional view along a line A-A of the prefabricated optical fiber20shown inFIG. 5.

The connecting piece31is fixedly connected to the head end341of the main shaft34and partially accommodated in the through hole344. The optical cable2extends into the through hole344and is connected to the connecting piece31. In this embodiment of this application, the term “fixedly connected” indicates that a relative location relationship between two assembled components is fixed, and a connection between the two components may be a detachable connection, or a non-detachable connection. In an embodiment, one end of the connection base311of the connecting piece31is inserted into the through hole344, and the one or more connection terminals312are fastened to the other end of the connection base311. The limiting plane3116of the connection base311abuts against a top end face of the main shaft34(that is, a top end face that is of the head end341and that is away from the tail end342). In this case, the connecting piece31and the main shaft34are located to each other in the axial direction of the optical fiber connector3. Referring toFIG. 6, the second locating hole31114of the fastening portion3111of the connecting piece31aligns with the first locating hole3452of the lug345of the main shaft34. A bolt350may be inserted into the first locating hole3452and the second locating hole31114such that the connecting piece31and the main shaft34are located to each other in the axial direction and a circumferential direction (perpendicular to and around the axial direction of the optical fiber connector31) of the optical fiber connector31.

During assembly, the insertion block3115(refer toFIG. 9AandFIG. 9B) on the connection base311of the connecting piece31is inserted into the insertion slot3414(refer toFIG. 7) on the head end341of the main shaft34. The insertion block3115is fitted to the insertion slot3414such that the main shaft34and the connecting piece31are located to each other in the circumferential direction of the optical fiber connector31.

Referring toFIG. 12toFIG. 14,FIG. 13is a schematic diagram of a structure of the lock cap39shown inFIG. 6, andFIG. 14is a schematic diagram of an internal structure of the lock cap39shown inFIG. 13.

The lock cap39is a hollow cylinder. The lock cap39is sleeved on the outer side of the main shaft34and the outer side of the connecting piece31. The lock cap39includes a sealing portion391and a connection portion392that is connected to a side of the sealing portion391. The lock cap39further includes a limiting portion393connected to a side that is of the sealing portion391and that is away from the connection portion392. The connection portion392, the sealing portion391, and the limiting portion393are sequentially arranged in the axial direction of the optical fiber connector3. The inner through-hole395of the lock cap39penetrates from an end of the connection portion392to an end of the limiting portion393. The sealing portion391is rotationally connected to the outer side of the head end341of the main shaft34. The connection portion392is located on a side that is of the head end341and that is away from the tail end342. The connection portion392wraps around the connecting piece31. The limiting portion393is located on an outer side of the transition section343. Referring toFIG. 2, when the optical fiber connector3is connected to the adapter1, the connecting piece31is partially inserted into the input end141of the adapter body14, and the input end141of the adapter body14is inserted into the connection portion392of the lock cap39. The connection portion392is configured to partially accommodate the adapter1when the connecting piece31is inserted into the adapter1.

In this embodiment, an inner diameter of the connection portion392is greater than an inner diameter of the sealing portion391. The inner diameter of the sealing portion391is greater than an inner diameter of the limiting portion393. The inner through-hole395of the lock cap39is a hole with varying diameters. In another embodiment, the inner through-hole395of the lock cap39may alternatively be a through-hole in another shape.

In this embodiment, an outer diameter D1of the sealing portion391is less than an outer diameter D2of the connection portion392. An outer diameter D3of the limiting portion393may be further less than the outer diameter D1of the sealing portion391. That is, the outer diameter D2of the connection portion392, the outer diameter D1of the sealing portion391, and the outer diameter D3of the limiting portion393sequentially decreases. An outer circumferential surface of the lock cap39has a step-shaped structure, to meet a requirement for accommodation capacity of the lock cap39(where the lock cap39is required to accommodate most components of the optical fiber connector3), and minimize a volume of the lock cap39. Therefore, the optical fiber connector3is more compact.

Optionally, a lock protrusion394is disposed on an inner side of the connection portion392. The lock protrusion394is located on a hole wall of the inner through-hole395of the lock cap39. In this embodiment, there are two lock protrusions394. The two lock protrusions394are disposed opposite to each other. In another embodiment, there may be one or more than three lock protrusions394.

Referring toFIG. 2,FIG. 3, andFIG. 13, the lock protrusion394is configured to be snap-fitted to the lock slot1412of the adapter1when the lock cap39is rotated by a first angle relative to the adapter1. The first angle is less than or equal to 90°. In an embodiment, when the optical fiber connector3is connected to the adapter1, the connecting piece31is partially inserted into the penetration hole143of the adapter body14, the connection portion392partially accommodates the input end141of the adapter body14and the lock protrusion394is located in the lock slot1412. The lock protrusion394is snap-fitted to the lock slot1412when the lock cap39is rotated by the first angle relative to the adapter body14. The first angle is less than or equal to the second angle. The lock protrusion394slides from the slide-in area1413to the lock slot1412. When the lock cap39is rotated relative to the adapter body14, the lock protrusion394slides through the slide area1414to the snap-fit area1415, and then is snap-fitted to the snap-fit surface1416of the snap-fit area1415. That is, the penetration hole143of the adapter body14may be configured to accommodate a part of the connecting piece31of the optical fiber connector3when the input end141is inserted into the lock cap39of the optical fiber connector3. The lock slot1412of the adapter body14is configured to accommodate the lock protrusion394on the inner side of the lock cap39and be snap-fitted to the lock protrusion394.

In this embodiment, the first angle of rotation of the lock cap39relative to the adapter body14is limited by a structure of the lock slot1412, and the lock slot1412extends the second angle in the circumferential direction of the input end141of the adapter body14such that the first angle is less than or equal to the second angle. The lock cap39is connected to the adapter body14in a rotary snap-fit lock manner. Therefore, the structure of the lock slot1412can be designed, to set or change a size of the first angle, thereby changing the angle of rotation required when the lock cap39is connected to the adapter body14.

In this embodiment, the lock cap39is connected to the adapter body14in a rotary snap-fit lock manner, the angle of rotation of the lock cap39relative to the adapter body14is less than or equal to the second angle, and the second angle is less than or equal to 90° such that the lock cap39only needs to be rotated by an angle less than one fourth of a circle relative to the adapter body14, to complete assembly or disassembly of the optical fiber connector3and the adapter1. Therefore, assembly and disassembly of the optical fiber connection assembly200are simple and time-saving (approximately one fifth of a time required by a conventional optical fiber connection assembly, or even a shorter time), the snap-fit connection between the optical fiber connector3and the adapter1is highly stable and secure, and signal transmission of the optical fiber connection assembly200is highly reliable.

Further, no conventional elastic arm is disposed on the connection terminal312(refer toFIG. 9B) of the optical fiber connector3in this embodiment. A lock requirement between the optical fiber connector3and the adapter1is met using a rotary snap-fit lock structure such that a conventional two-step assembly/disassembly process (elastic arm assembly/disassembly and protective cover assembly/disassembly) is simplified into a one-step assembly/disassembly process, thereby further reducing difficulty of and a time for assembly and disassembly of the optical fiber connector3and the adapter1. In addition, no elastic arm structure is disposed on the connection terminal312such that a volume of the connection terminal312is reduced. Therefore, a port density can be increased without increasing a volume of the optical fiber connector3.

A snap-fit matching surface matching the snap-fit surface1416may be further disposed on the lock protrusion394, to improve snap-fit stability between the lock protrusion394and the adapter body14. It can be understood that a structure of the lock protrusion394matches the structure of the lock slot1412, and a rotary snap-fit lock connection structure for the lock cap39and the adapter body14is the same as a rotary snap-fit lock connection structure for the protective cap16of the adapter1and the adapter body14.

An indicative arrow mark3922is disposed on an outer sidewall3921of the connection portion392. When the optical fiber connector3is connected to the adapter1, if the indicative arrow mark3922is aligned with the arrow sign1417on the outer sidewall1411of the input end141, the lock cap39can be aligned with the adapter body14, to be quickly mounted on the adapter body14. When the indicative arrow mark3922is used with the alignment arrow mark1441on the stop flange144of the adapter body14, a connection/disconnection state of the lock cap39and the adapter body14can be indicated.

Shallow grooves are disposed on both the outer sidewall3921of the connection portion392and an outer sidewall3911of the sealing portion391. In an embodiment, a shallow groove3923of the connection portion392and a shallow groove3912of the sealing portion391are connected and continuously extend in an axial direction of the lock cap39(that is, the axial direction of the optical fiber connector3). In another embodiment, the shallow groove3923of the connection portion392and the shallow groove3912of the sealing portion391may alternatively have another shape and another connection relationship. An outer sidewall of the limiting portion393includes a plurality of symmetrically arranged edge-cut planes3931. There are four edge-cut planes3931. Two edge-cut planes3931that are opposite to each other form one group of edge-cut planes3931. A shallow groove3932is disposed on each edge-cut plane3931. The shallow groove3932may extend in a direction perpendicular to the axial direction. This provides a user with better hand feel and the lock cap39is not likely to slide when the user holds or operates the lock cap39.

Referring toFIG. 12andFIG. 14, optionally, a stop plane3913facing the connection portion392is disposed on the sealing portion391. The stop plane3913is a part of the hole wall of the inner through-hole395of the lock cap39. When the main shaft34is mounted in the lock cap39(that is, the main shaft34is inserted into the inner through-hole395of the lock cap39), the limiting bump3412and the limiting flange3413(refer toFIG. 7) on the head end341of the main shaft34abut against the stop plane3913of the lock cap39such that the main shaft34and the lock cap39are located to each other.

Optionally, referring toFIG. 14, a second limiting surface3924facing the sealing portion391is disposed on the limiting portion393. The second limiting surface3924may be a part of an end face that is of the limiting portion393and that is connected to the sealing portion391. The second limiting surface3924is a part of the hole wall of the inner through-hole395of the lock cap39.

Referring toFIG. 8,FIG. 12, andFIG. 14, the optical fiber connector3further includes the elastic part35. The elastic part35is located between the transition section343and the sealing portion391, and two ends of the elastic part35abut against the first limiting surface3431and the second limiting surface3924respectively.

In this embodiment, the elastic part35is disposed such that the first limiting surface3431and the second limiting surface3924tend to move away from each other, and the lock cap39tends to move toward the tail end342of the main shaft34. Therefore, when the lock cap39is connected to the adapter1(refer toFIG. 3), the lock protrusion394can be stably snap-fitted to the lock slot1412of the adapter body14, and the connecting piece31and the adapter body14are fastened to each other in the axial direction of the optical fiber connector3such that a connection relationship between the lock cap39and the adapter1is reliable, thereby achieving good shockproof and anti-looseness effects.

Referring toFIG. 2,FIG. 12, andFIG. 15,FIG. 15is a schematic diagram of a structure of the dust cap32shown inFIG. 6.

Optionally, one end371of the lanyard37of the optical fiber connector3is sleeved on the outer side of the main shaft34, and the other end372of the lanyard37is connected to the dust cap32. In an embodiment, the dust cap32includes an insertion portion321and a holding portion322. A top side of the insertion portion321is open. The holding portion322is connected to a bottom side of the insertion portion321. A connection groove323is disposed between the insertion portion321and the holding portion322. The connection groove323is a continuous annular groove. The end372that is of the lanyard37and that is away from the main shaft34is located in the connection groove323, to connect the dust cap32.

Optionally, a dustproof lock slot324is disposed on an end of the dust cap32. The end of the dust cap32can extend into the connection portion392, and the dustproof lock slot324is snap-fitted to the lock protrusion394. In an embodiment, the dustproof lock slot324is disposed on an outer sidewall3211of the insertion portion321. The dustproof lock slot324extends a third angle in a circumferential direction of the insertion portion321. The third angle may be less than or equal to 90°. The outer sidewall3211of the insertion portion321is a cylindrical surface. The circumferential direction of the insertion portion321is a direction perpendicular to and around a central axis of the outer sidewall3211of the insertion portion321. The third angle is a central angle of the dustproof lock slot324. The third angle may be an angle from 30° to 90°, such as 30°, 45°, 60°, 75°, or 90°. The dustproof lock slot324includes a slide-in area3241, a slide area3242, and a snap-fit area3243that are sequentially connected. The slide area3242and the snap-fit area3243extend in the circumferential direction of the insertion portion321. The slide-in area3241connects the slide area3242to an end face of the insertion portion321. A snap-fit surface3244facing away from the slide-in area3241is disposed on the snap-fit area3243. For example, a direction from the slide area3242to the snap-fit area3243is a slide-in direction, and an orientation of the snap-fit surface3244is opposite to the slide-in direction.

When the dust cap32is connected to the lock cap39, the insertion portion321of the dust cap32completely or partially extends into the connection portion392of the lock cap39. The connecting piece31partially extends into the insertion portion321. The lock protrusion394of the lock cap39slides from the slide-in area3241to the dustproof lock slot324. When the dust cap32is rotated relative to the lock cap39(or the lock cap39is rotated relative to the dust cap32), the lock protrusion394slides through the slide area3242to the snap-fit area3243, and then is snap-fitted to the snap-fit surface3244of the snap-fit area3243. A snap-fit matching surface matching the snap-fit surface3244may be further disposed on the lock protrusion394of the lock cap39, to improve snap-fit stability between the lock protrusion394and the dust cap32.

It can be understood that, in this embodiment of this application, the lock cap39of the optical fiber connector3of the optical fiber connection assembly200is connected to the adapter body14of the adapter1using a rotary snap-fit lock structure, the lock cap39of the optical fiber connector3is connected to the dust cap32of the optical fiber connector3also using a rotary snap-fit lock structure, and the protective cap16of the adapter1is connected to the adapter body14also using a rotary snap-fit lock structure. Therefore, a connection structure of the protective cap16of the adapter1is similar to a connection structure of the lock cap39of the optical fiber connector3, and a connection structure of the dust cap32of the optical fiber connector3is similar to a connection structure of the adapter body14of the adapter1. In this embodiment, a connection between the optical fiber connector3and the adapter1, a connection between components of the optical fiber connector3, and a connection between components of the adapter1are implemented using same rotary snap-fit lock structures such that a structure of the optical fiber connection assembly200is further simplified and installation is less difficult.

In an embodiment, the third angle is equal to the second angle such that the connection action between the dust cap32and the lock cap39is the same as the connection action between the adapter body14and the lock cap39, thereby improving user experience.

Further, there may be one, two, or more than three dustproof lock slots324. This embodiment is described using an example in which there are two dustproof lock slots324. The two dustproof lock slots324are disposed facing away from each other. In addition, the two dustproof lock slots324are centrosymmetrically distributed. In an embodiment, when rotated by 180° around the central axis of the outer sidewall3211of the insertion portion321, one dustproof lock slot324overlaps the other dustproof lock slot324. A quantity of the dustproof lock slots324may be designed based on the second angle, provided that a plurality of dustproof lock slots324are designed to be spaced apart from each other. For example, when the second angle is less than 60°, there may be three dustproof lock slots324.

Optionally, the dust cap32further includes a middle portion325located between the insertion portion321and the holding portion322. An alignment arrow mark3252is disposed on an outer sidewall3251of the middle portion325. The alignment arrow mark3252is configured to indicate a connection/disconnection state of another component and the dust cap32.

Referring toFIG. 6,FIG. 12, andFIG. 15, the first sealing ring33of the optical fiber connector3is located in the connection portion392. When the optical fiber connector3is connected to the dust cap32, the first sealing ring33is compressed between the connection portion392and the dust cap32. A sealing connection groove3212is disposed on the outer sidewall3211of the insertion portion321of the dust cap32. The sealing connection groove3212is located between the middle portion325and the dustproof lock slot324. The first sealing ring33is mounted in the sealing connection groove3212.

When the optical fiber connector3is connected to the adapter1(refer toFIG. 3), the first sealing ring33is configured to be compressed between the connection portion392and the adapter1. In this case, the sealing ring15of the adapter1is detached from the sealing groove1418. The first sealing ring33is mounted in the sealing groove1418.

In this embodiment, the first sealing ring33is configured to seal a connection between the lock cap39and another component, to achieve waterproof and dustproof effects such that the optical fiber connector3can achieve a protection level of IP68 and has a longer service life and higher reliability.

Referring toFIG. 7,FIG. 12, andFIG. 14, the second sealing ring36of the optical fiber connector3is compressed between a groove wall of the sealing groove346and an inner side surface of the sealing portion391. The inner side surface of the sealing portion391is a part of the hole wall of the inner through-hole395of the lock cap39. In this case, the second sealing ring36can prevent external moisture, dust, or the like from entering the lock cap39through a gap between the lock cap39and the main shaft34such that the optical fiber connector3can achieve a protection level of IP68, thereby improving reliability of the optical fiber connector3.

Referring toFIG. 6,FIG. 12, andFIG. 16,FIG. 16is a schematic diagram of an internal structure of the sealing sleeve340shown inFIG. 6.

One end3401of the sealing sleeve340of the optical fiber connector3is sleeved on an outer side of the tail end342of the main shaft34in a sealing manner. The other end3402of the sealing sleeve340is configured to allow insertion of the optical cable2and be connected to the optical cable2in a sealing manner. The sealing sleeve340is a hollow cylinder. The optical cable2is inserted into and passes through an inner through-hole of the sealing sleeve340, and then enters the through hole344of the main shaft34. The sealing sleeve340is configured to implement a sealed connection between the optical cable2and the main shaft34, to improve reliability of the optical fiber connector3and extend a service life of the optical fiber connector3.

The sealing sleeve340may be a heat shrink tubing. The sealing sleeve340may be a tube with adhesive on an inner surface, to improve reliability of connections to both the tail end342of the main shaft34and the optical cable2. For the sealing sleeve340, an inner diameter of the end3401(a top end inFIG. 16) connected to the tail end342of the main shaft34is greater than an inner diameter of the end3402(a bottom end inFIG. 16) connected to the optical cable2. An inner diameter of a middle portion3403between the two ends (3401/3402) of the sealing sleeve340may be between the inner diameters of the two ends (3401/3402). An inner through-hole3404of the sealing sleeve340may be a hole with varying diameters. An outer sidewall of the sealing sleeve340is substantially step-shaped.

The sealing sleeve340is connected to a part of the metal portion3422and a part of the rubber portion3421in a sealing manner. In an embodiment, for the sealing sleeve340, the end3401connected to the tail end342of the main shaft34is connected to both a part of the metal portion3422and a part of the rubber portion3421in a sealing manner. In this case, a connection relationship between the sealing sleeve340and the tail end342of the main shaft34is more stable and reliable.

Referring toFIG. 6andFIG. 12, the optical cable2of the prefabricated optical fiber20may include the cable wire21, an aramid yarn22, a cable jacket23, a first support ring24, and a second support ring25. Both the cable wire21and the aramid yarn22are located in the cable jacket23. The aramid yarn22may be wrapped around the cable wire21. Both tensile strength and bending strength of the aramid yarn22are greater than those of the cable wire21. The aramid yarn22is configured to protect the cable wire21, to reduce a risk of breaking the cable wire21, and improve the tensile strength of the optical cable2. The cable jacket23wraps the cable wire21and the aramid yarn22, to provide protection.

The first support ring24is a metal ring. The first support ring24wraps around the cable wire21and the aramid yarn22and is located in the cable jacket23. The second support ring25is a metal ring. The second support ring25wraps around the cable wire21and the aramid yarn22and is located in the cable jacket23. The second support ring25and the first support ring24are disposed apart from each other. Both the second support ring25and the first support ring24provide support and protection.

Referring toFIG. 6,FIG. 12, andFIG. 17,FIG. 17is a schematic diagram of an internal structure of the metal crimp ring330shown inFIG. 6.

The metal crimp ring330of the optical fiber connector31is located in the sealing sleeve340. The metal crimp ring330is a hollow cylinder. One end3301of the metal crimp ring330is sleeved on an outer side of the metal portion3422of the tail end342of the main shaft34. The other end3302of the metal crimp ring330is configured to be sleeved on an outer side of the optical cable2, and the end3301of the metal crimp ring330can firmly press the aramid yarn22of the optical cable2against the metal portion3422.

In this embodiment, the metal crimp ring330firmly presses the aramid yarn22against the metal portion3422, thereby improving connection strength between the optical cable2and the main shaft34, and improving tensile strength of the optical fiber connector3.

For the metal crimp ring330, an inner diameter of the end3301(a top end inFIG. 17) connected to the metal portion3422is greater than an inner diameter of the other end3302(a bottom end inFIG. 17). An inner through-hole3303of the metal crimp ring330is a hole with varying diameters. An outer sidewall of the metal crimp ring330is step-shaped.

Referring toFIG. 6,FIG. 12, andFIG. 18,FIG. 18is a schematic diagram of an internal structure of the tail ferrule320shown inFIG. 6.

The tail ferrule320is a hollow cylinder. The tail ferrule320is sleeved on the outer side of the tail end342of the main shaft34and an outer side of the sealing sleeve340. The tail ferrule320is connected to the tail end342of the main shaft34in a sealing manner. The tail ferrule320is connected to the sealing sleeve340in a sealing manner. The tail ferrule320may be a formed sleeve member, and is sleeved on the outer side of the tail end342of the main shaft34and the outer side of the sealing sleeve340through assembly. Alternatively, the tail ferrule320may be directly formed on the outer side of the tail end342of the main shaft34and the outer side of the sealing sleeve340through decoration. In this embodiment, the tail ferrule320can provide protection and sealing effects, to improve tensile strength and sealing performance of the optical fiber connector3.

A shape and a size of an inner through-hole3201of the tail ferrule320are adapted to the tail end342of the main shaft34and the sealing sleeve340, and the tail ferrule320tightly wraps the tail end342of the main shaft34and the sealing sleeve340.

An inner snap-fit flange3202is disposed on one end that is of the tail ferrule320and that is sleeved on the tail end342of the main shaft34. The inner snap-fit flange3202extends into the inner through-hole3201of the tail ferrule320.

Referring toFIG. 6,FIG. 12, andFIG. 19,FIG. 19is a schematic diagram of an internal structure of the snap ring38shown inFIG. 6.

The optical fiber connector3further includes the snap ring38. The snap ring38is mounted in the limiting groove3423of the tail end342of the main shaft34(refer toFIG. 7). The snap ring38is fastened relative to the main shaft34. An outer sidewall of the snap ring38forms a step-shaped structure. The outer sidewall of the snap ring38has a step-shaped surface381. The step-shaped surface381faces the transition section343of the main shaft34. The inner snap-fit flange3202of the tail ferrule320abuts against the step-shaped surface381. In this case, the tail ferrule320may be further fastened relative to the main shaft34using the snap ring38, to reduce a risk that the tail ferrule320accidentally detaches from the main shaft34, thereby improving tensile strength of the optical fiber connector3.

Referring toFIG. 6,FIG. 12, andFIG. 20,FIG. 20is a schematic diagram of an internal structure of the adhesive container310shown inFIG. 6.

The adhesive container310is located in the main shaft34. The adhesive container310includes a body portion3101and at least two support portions3102fastened to an inner side of the body portion3101. The at least two support portions3102are arranged apart from each other in an axial direction of the body portion3101. The cable wire21of the optical cable2may extend into the body portion3101, and be laid over or sequentially pass through the at least two support portions3102. The adhesive container310is configured to support and fasten a part that is of the cable wire21and that is in the through hole344of the main shaft34such that the cable wire21is fastened relative to the main shaft34, thereby protecting the cable wire21from damage due to frequent shaking or impact, and improving reliability of the optical fiber connector3.

A third locating hole3103is disposed in the body portion3101. A corresponding fourth locating hole3104(refer toFIG. 6) is disposed in the main shaft34. The fourth locating hole3104is disposed in the transition section343of the main shaft34. The adhesive container310may be fastened relative to the main shaft34by inserting a latch sequentially in the fourth locating hole3104of the main shaft34and the third locating hole3103.