JP5103213B2 - Optical fiber cable with connector, optical connector, and method of assembling optical connector - Google Patents

Description

  The present invention relates to a field-assembled optical fiber cable with connector and optical connector, and an optical connector assembling method, and more particularly to an optical fiber cable with optical connector and optical connector using fusion splicing, and an optical connector assembling method.

Conventionally, as an example of a structure capable of assembling an optical connector at the tip of an optical fiber at a connection site, the optical fiber and a built-in optical fiber inserted in a ferrule are connected by fusion. (See, for example, Patent Documents 1 and 2).
Patent Document 1 discloses an optical connector having a structure in which a fusion splicing portion reinforced with a reinforcing body such as a resin is accommodated in a connector housing. This structure protects the fusion splicing portion with the connector housing, and can give high strength to this portion.
Patent Document 2 discloses an optical connector having a structure in which a fusion splicing portion is disposed in a slot formed in a ferrule.
JP 2002-82257 A US Pat. No. 5,748,819

In the optical connector described in Patent Document 1, the fusion splicing portion is accommodated in the connector housing. Although this structure is effective for improving the strength, since the size of the fusion spliced portion reinforced with the reinforcing body is large, a large connector housing is used to accommodate this, so the overall size is large. Become. For this reason, a large wiring space is required when used in an optical junction box or the like, and there is a problem in terms of space saving.
The optical connector disclosed in Patent Document 2 requires a fusion work at a position close to the ferrule. For this reason, if a general-purpose discharge electrode is used for the fusion work, there is a possibility that the ferrule may be adversely affected, so that a general fusion splicer cannot be used and the fusion work is not easy. .
The present invention has been made in view of the above circumstances, and can be miniaturized as a whole, has sufficient strength, and is easy to perform fusion splicing work. It aims to provide a method.

The present invention is an optical fiber cable with a connector in which an optical connector is assembled at an end of an optical fiber cable in which an optical fiber and a tensile body extending along the longitudinal direction of the optical fiber are integrated. the connector comprises a housing, a ferrule that is movable in the longitudinal direction in the housing, and a biasing means for biasing the ferrule forwardly taking a reaction force to said housing, interpolation in the ferrule The built-in optical fiber is extended rearward through a through hole provided in the rear end portion of the housing, and the rear end portion of the extended built-in optical fiber is led out to the optical fiber cable terminal. The housing and the optical fiber cable are fused and connected to the tip of an optical fiber, and a heat-shrinkable reinforcing tube that accommodates the fused connection is used. Are connected to respective rear end portions and the outer skin the front end of the optical fiber cable of the housing, the reinforcing tube is fixed overlaid respectively, rear end portions and the optical fiber cable of the housing within the stiffening tube A reinforcing material made of a thermoplastic resin is filled between the front end portions of the outer skin of the outer shell, and the tensile body drawn out from the optical fiber cable end extends along the longitudinal direction of the optical fiber and the built-in optical fiber. And an optical fiber with a connector that is fixed in the reinforcing member in the reinforcing tube in a state where the front end thereof is disposed on the front side of the fusion splicing point and does not reach the rear end of the housing. Provide cables.
It is preferable that a reinforcing core member extending from the front side of the rear end of the housing to the rear side of the front end of the outer cover of the optical fiber cable is provided in the reinforcing tube .
The through hole provided at the rear end of the housing preferably has an inner diameter that is substantially equal to the outer diameter of the built-in optical fiber .
In the optical fiber cable with a connector of the present invention, the built-in optical fiber and the coating of the optical fiber are removed in the vicinity of the fusion splicing point, and the strength member drawn out from the end of the optical fiber cable has its front end. Is preferably fixed in a state where it is disposed at a position where the coating of the built-in optical fiber is not removed .
In the optical fiber cable with a connector of the present invention, it is preferable that one or a plurality of annular protrusions are formed on the outer surface of the housing, and the reinforcing tube is fixed to the housing at the annular protrusions.
In the optical fiber cable with a connector according to the present invention, the ferrule includes a capillary portion having a joining end surface at a front end, and a flange portion formed at a rear end portion of the capillary portion, and the flange portion is provided behind the ferrule. It is preferably located at the end.
It is preferable that the housing is provided with a protective cylinder portion that can accommodate at least a part of the reinforcing tube.

The present invention relates to a method of assembling an optical connector at an end of an optical fiber cable in which an optical fiber and a tensile body extending along the longitudinal direction of the optical fiber are integrated. The optical connector includes a housing, a ferrule which is movable in longitudinal direction within said housing, taking a reaction force on said housing and a biasing means for biasing the ferrule forwardly, inserted in the ferrule a built-in optical fiber but extends out rearward via a through hole provided in the rear portion of the housing, the tip of the optical fiber which the rear end portion, and lead-out to the optical fiber cable terminal of the built-in optical fiber out the extension The heat-shrinkable reinforcing tube is disposed in such a manner that the fusion-bonding portion is accommodated, and the reinforcing tube is reinforced with a thermoplastic resin. Placed, heating the reinforcing tube, by contracting each of the rear end portion and the outer skin the front end of the optical fiber cable of the housing, it is fixed by covering the reinforcing tube respectively, wherein within the stiffening tube A reinforcing material made of a thermoplastic resin is filled between the rear end of the housing and the outer front end of the optical fiber cable, and the tensile body drawn out from the end of the optical fiber cable includes the optical fiber and the built-in optical fiber. The front end of the reinforcing tube is fixed in the reinforcing material in the reinforcing tube in a state where the front end is located in front of the fusion splicing point and does not reach the rear end of the housing. Assembling the optical connector for connecting the housing and the optical fiber cable with the reinforcing tube To provide.

In the present invention, the built-in optical fiber is previously passed through the ferrule of the optical connector, and the end of the built-in optical fiber opposite to the connection end surface of the ferrule and the optical fiber of the exposed optical fiber cord are fused and connected. Then, the outer periphery of the fusion splicing part and its vicinity is covered with a reinforcing tube containing a reinforcing material made of thermoplastic resin and a reinforcing core material in advance, and then the reinforcing tube is raised to a predetermined temperature with a heater to cause heat shrinkage. In the connection method for protecting the optical fiber fusion splicing portion and the vicinity thereof, the ferrule is provided in the optical connector housing so as to be movable in the front-rear direction, and exerts a reaction force on the stop ring of the optical connector. The built-in optical fiber is urged forward by an urging means that takes, through a through hole provided in a rear end portion of the stop ring of the optical connector. Write and extends, the reinforcing tube the reinforcing core is disposed on the outer periphery of the stop ring of the optical connector, and wherein the reinforcing material was dissolved stiffening tube by heat in heating shrinkage, after left at room temperature The stop ring and the reinforcing core material are interposed and fixed, and the reinforcing tube is housed in the boot of the optical connector, and the reinforcing member is respectively provided at the rear end portion of the stop ring and the front end portion of the outer cover of the optical fiber cord. The tube was covered and fixed, and the reinforcing material was filled between the rear end portion of the stop ring and the front end portion of the outer sheath of the optical fiber cord in the reinforcing tube, and was led out from the end of the optical fiber cord. The tensile body extends along the longitudinal direction of the optical fiber of the optical fiber cord and the built-in optical fiber, and Is disposed within the reinforcing tube is fixed to the reinforcing member, the length of the strength member, the optical connector is a length that its front end does not reach the stop ring rear portion a front than the fusion splicing point A method for connecting an optical fiber and an optical fiber cord is provided.
It is preferable that the reinforcing core material in the reinforcing tube reaches the stop ring and overlaps.
It is preferable that the built-in optical fiber previously passed through the ferrule of the optical connector is fixed with an adhesive or the like in the stop ring.
On the outer peripheral surface of the stop ring, there is one concave, convex, or concave / convex shape of a circular shape, an elliptical shape, a polygonal shape, a circumferential direction, a straight line in the longitudinal direction, a spiral shape, a curved line, a net shape, or a combined shape. It is preferable that two or more are engraved.

  The present invention provides a connection portion between an optical fiber of an optical connector and an optical fiber cord manufactured by the above-described method for connecting an optical fiber of an optical connector and an optical fiber cord.

According to the present invention, a built-in optical fiber is previously passed through a ferrule of an optical connector, the ferrule is provided in the housing of the optical connector so as to be movable in the front-rear direction, and takes a reaction force on a stop ring of the optical connector. The built-in optical fiber is urged forward by the urging means, and extends backward through a through hole provided in the rear end portion of the stop ring of the optical connector, and is opposite to the connection end surface of the ferrule. The end of the built-in optical fiber is fusion spliced to the optical fiber of the optical fiber cord that has been led out, and the heat and the reinforcing core made of thermoplastic resin are built in the fusion splicing portion and the outer periphery in the vicinity thereof. A shrinkable reinforcing tube is covered, and the reinforcing tube is formed from the stop ring of the optical connector to the optical fiber cord. A stop ring between the reinforcing core is interposed secured, each of the outer skin front end of the rear portion and the optical fiber cord of the stop ring, with the reinforcing tube is fixed overlaid respectively, the reinforcing material Is filled between the rear end portion of the stop ring and the outer front end portion of the optical fiber cord in the reinforcing tube, and the tensile body led out from the end of the optical fiber cord is an optical fiber of the optical fiber cord and It extends along the longitudinal direction of the built-in optical fiber, is disposed in the reinforcing tube and is fixed to the reinforcing material, and the length of the strength member is such that its front end is in front of the fusion splicing point. An optical fiber cord with a connector having a length that does not reach the rear end of the stop ring .

According to the present invention, a built-in optical fiber is previously passed through a ferrule of an optical connector, the ferrule is provided in the housing of the optical connector so as to be movable in the front-rear direction, and takes a reaction force on a stop ring of the optical connector. The built-in optical fiber is urged forward by the urging means, and extends backward through a through hole provided in the rear end portion of the stop ring of the optical connector, and is opposite to the connection end surface of the ferrule. The end of the built-in optical fiber can be fusion spliced to the optical fiber of the optical fiber cord that has been led out, and a reinforcing material made of thermoplastic resin and a reinforcing core material are incorporated in the outer periphery of the fusion splicing portion and its vicinity. The heat-shrinkable reinforcing tube can be covered, and the reinforcing tube can be formed from the stop ring of the optical connector to the optical fiber cord. Fixing said reinforcement, said a stop ring and between the reinforcing core can intervening secured, each of the outer skin front end of the rear portion and the optical fiber cord of the stop ring, the reinforcing tube is placed over each The reinforcing member is filled between the rear end portion of the stop ring and the outer front end portion of the optical fiber cord in the reinforcing tube, and the tensile body pierced from the optical fiber cord end is It extends along the longitudinal direction of the optical fiber of the optical fiber cord and the built-in optical fiber, and is disposed in the reinforcing tube and fixed to the reinforcing material. Provided is an optical connector having a length in front of a landing connection point and does not reach a rear end portion of a stop ring .

In the optical fiber cable with connector of the present invention, the housing and the optical fiber cable are connected by the reinforcing tube, and the reinforcing material is filled in the reinforcing tube. Sufficient tensile strength can be given to the connection portion with the cable.
Moreover, since the tensile body drawn out from the optical fiber cable end is fixed in the reinforcing material, not only the end treatment of the tensile body is simplified, but also the tensile strength can be increased.
Therefore, even when a large tensile force is applied to the connection portion, the fusion spliced portion is not damaged or the optical fiber is not cut.
Further, in this optical fiber cable with a connector, since the fusion splicing portion is arranged in a reinforcing tube provided outside the housing, the size of the housing is larger than that of the structure in which the splicing splicing portion is accommodated in the housing. Since the total length can be shortened, the entire connector portion at the tip of the optical fiber cable can be reduced in size.
Therefore, the optical fiber can be accommodated in a narrow storage space such as an optical junction box or a rosette without applying an excessive bending to the optical fiber.
Furthermore, since a general-purpose fusing holder can be diverted to the fusing work, the fusing work becomes easier as compared with the structure in which the fusion splicing portion is arranged in the ferrule.
Another advantage of the optical fiber cable with a connector according to the present invention is that the number of parts is small and the assembly work is easy.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a sectional view showing an optical fiber cable with a connector according to a first embodiment of the present invention. FIG. 2 is a perspective view showing an appearance of the optical fiber cable with a connector.
As shown in FIGS. 1 and 2, this optical fiber cable with a connector is obtained by assembling the optical connector 1 at the end of an optical fiber cable 21.
In the following description, the left side in FIG. 1 may be referred to as “front” or “tip direction”, and the right side may be referred to as “rearward”.
The optical fiber cable 21 has a structure in which an optical fiber 22 such as an optical fiber core and a tensile body 23 extending along the longitudinal direction of the optical fiber 22 are accommodated in an outer sheath 24 made of a resin such as polyethylene. For example, a general optical fiber cord can be exemplified.
As the tensile body 23, an aramid fiber is preferably used, but a glass fiber, a carbon fiber, or the like can also be used.

  The optical connector 1 terminates an optical fiber 22 so that it can be connected to a connector, and includes a sleeve-like coupling 2, a housing 3 provided in the coupling 2, and a ferrule 4 provided in the housing 3. And a coil spring 5 (biasing means) for biasing the ferrule 4 forward, and a protective cylinder portion 18 provided on the rear end side of the housing 3.

The housing 3 includes a sleeve-like plug frame 6 and a stop ring 7 attached to the rear end side of the plug frame 6.
The stop ring 7 includes a sleeve-like main body portion 8 and a cylindrical fixing portion (hereinafter sometimes referred to as a tube fixing portion) 9 extending rearward from the main body portion 8.
On the inner surface of the main body portion 8, a locking step portion 8 a that the rear end portion of the coil spring 5 is locked is formed.

The tube fixing part 9 has a diameter smaller than that of the main body part 8, and it is preferable to form an uneven part 16 on the outer surface of the tube fixing part 9. The shape of the concavo-convex portion 16 is not particularly limited, but is preferably formed over the circumferential direction of the tube fixing portion 9. In the illustrated example, a plurality of annular convex portions 9a are formed at intervals in the front-rear direction.
By forming the annular convex portion 9a, the fixing force between the reinforcing tube 10 and the tube fixing portion 9 can be increased, and the tensile strength against the force in the pulling direction (right side in FIG. 1) can be improved. When the reinforcing tube 10 has a shape along the annular convex portion 9a, the tensile strength is further increased.
In the illustrated example, the annular convex portion 9a has a rectangular cross section, but the shape of the annular convex portion is not limited thereto, and may be a semicircular shape, an inverted V shape, or the like. The number of annular protrusions may be one or plural.

The protective cylinder portion 18 is formed in a cylindrical shape extending rearward from the main body portion 8 of the stop ring 7 and can accommodate a part of the tube fixing portion 9 and the reinforcing tube 10. The protection cylinder part 18 is formed so that the fusion splicing part 15 mentioned later can be accommodated. A locking hole 18a is formed at the front end portion of the protective cylinder portion 18 so that the locking projection 8b formed on the outer surface of the main body portion 8 of the stop ring 7 is fitted. The locking hole 18a is locked. It can be attached to the main body portion 8 by fitting into the convex portion 8b.
A front portion of the protective cylinder portion 18 is provided in the coupling 2, and a rear portion extends rearward from the rear end of the coupling 2.
The protective cylinder 18 may be formed so as to be able to accommodate the entire reinforcing tube 10.

The ferrule 4 includes a cylindrical capillary part 13 having a connection end surface 13a at the tip, and a metal flange part 14 attached to the rear end part 13b of the capillary part 13. The flange portion 14 has a shape generally used in a single-core optical connector ferrule.
An optical fiber introduction hole 13b (fine hole) is formed in the capillary portion 13 along the central axis, and a distal end portion 12a of the built-in optical fiber 12 such as an optical fiber core wire (for example, in the optical fiber introduction hole 13b) An optical fiber bare wire) is inserted and fixed.
The front end of the built-in optical fiber 12 is exposed at the connection end surface 13 a of the capillary section 13, and the rear end side extends backward from the rear end of the stop ring 7 through the stop ring 7.

The capillary part 13 is made of ceramic such as zirconia or glass, for example. These materials can be selected and used according to the use environment.
The flange portion 14 protrudes outward from the outer surface of the capillary portion 13, and an engagement recess portion (not shown) that engages with an engagement projection portion (not shown) of the plug frame 6 is formed. The rotation around the axis is restricted.
The flange portion 14 is located at the rear end portion of the ferrule 4.
The ferrule 4 is restricted from further movement in the distal end direction when the flange portion 14 abuts against the stopper projection 6 a of the plug frame 6.

In this type of optical connector, a capillary part, a flange part attached to the rear end of the capillary part, and an integral structure with the flange part, extending behind the flange part and inserting the built-in optical fiber A ferrule that is combined with a cylindrical portion may be used.
However, it is necessary to use a large housing in order to store the extension cylinder part in the housing.
On the other hand, the ferrule 4 in the illustrated example is of a type in which the end portion of the flange portion 14 is located at the rear end portion of the ferrule 4 and does not include an extended tube portion. For this reason, a small housing 3 having a short overall length can be used, and the entire optical connector 1 can be miniaturized.

  The rear end portion 12b of the built-in optical fiber 12 is fusion-bonded to a front end portion 22a of the optical fiber 22 that is led out to the end of the optical fiber cable 21. The fusion splicing part is indicated by reference numeral 15. The distal end portion 22a is, for example, a bare optical fiber drawn from an optical fiber core wire.

  The coil spring 5 applies a reaction force to the main body portion 8 of the stop ring 7 to press the flange portion 14 forward, and biases the ferrule 4 forward, and connects the optical connector 1 to another optical connector. Sometimes, the ferrule 4 is given a butting force with the counterpart optical connector.

The tube fixing portion 9 of the stop ring 7 and the outer sheath 24 of the tip portion of the optical fiber cable 21 are covered with a sleeve-like reinforcing tube 10. The reinforcing tube 10 contains the optical fibers 12 and 22 and the fusion splicing portion 15.
As the reinforcement tube 10, what consists of heat-shrinkable resin is used, for example, the polyolefin etc. which shrink | contract at 100-160 degreeC can be used.

The front end portion of the reinforcing tube 10 is put on the tube fixing portion 9 and is in close contact with and joined to the outer surface (side surface) of the tube fixing portion 9. The reinforcement tube 10 can improve the tensile strength against the force in the pulling direction (right side in FIG. 1) by being fixed to the portion where the annular convex portion 9a is formed.
The rear end portion of the reinforcing tube 10 is put on the tip portion of the optical fiber cable 21.

The reinforcing tube 10 is filled with a reinforcing material 11 made of a thermoplastic resin. The reinforcing material 11 is filled from the tube fixing portion 9 to the outer surface of the tip end portion of the optical fiber cable 21.
The strength member 23 drawn out from the end of the optical fiber cable 21 is fixed in a state of being embedded in the reinforcing material 11. The front-rear direction position of the tip of the strength member 23 is in front of the fusion splicing portion 15. The distal end portion of the strength member 23 may be sandwiched between the reinforcing tube 10 and the tube fixing portion 9.
The reinforcing material 11 is preferably interposed between the inner surface of the reinforcing tube 10 and the outer surface of the tube fixing portion 9 (not shown). As a result, the reinforcing material 11 extends to the outer surface of the tube fixing portion 9, thereby increasing the adhesive strength and bonding force between the main body portion (fused connection portion side) of the reinforcing material 11 and the stop ring 7, and in the drawing direction. Excellent tensile strength against force.

  In the illustrated example, the reinforcing material 11 is interposed between the inner surface of the reinforcing tube 10 and the outer surface of the optical fiber cable 21. With the configuration in which the outer surface of the tip portion of the optical fiber cable 21 is embedded with the reinforcing material 11, the bonding strength and bonding strength between the main body portion (fusing connection portion side) of the reinforcing material 11 and the optical fiber cable 21 are increased. The tensile strength against the force in the pulling direction can be increased. Furthermore, as a whole, not only the tensile strength but also the resistance to mechanical stress from other directions can be improved.

The reinforcing material 11 softens above a predetermined temperature and solidifies below this temperature. The reinforcing material 11 is preferably softened at the contraction temperature of the reinforcing tube 10. This softening temperature is, for example, 100 to 160 ° C.
As the reinforcing material 11, a hot melt resin (hot melt adhesive) can be used. Examples of the hot melt resin include those mainly composed of a resin such as ethylene-vinyl acetate copolymer (EVA), polyethylene, polyisobutylene, polyamide, and ethylene-acrylic acid ester copolymer.

In the reinforcing tube 10, a reinforcing core (not shown) extending from the outer surface of the tube fixing portion 9 to the outer surface of the end portion of the optical fiber cable 21 is provided in the same manner as a commonly used reinforcing member of the fusion splicing portion. Is preferred.
The reinforcing core material is for increasing the strength of the connection portion between the optical connector 1 and the optical fiber cable 21, and is made of a hard material such as metal or glass, and the shape thereof can be a rod shape, a long plate shape, or the like. It is preferable that the reinforcing core material has a length covering almost the entire length of the reinforcing tube 10. Thereby, the mechanical strength of the connection portion is further improved.

  The boot 19 attached to the optical fiber cable 21 is attached to the protective cylinder portion 18 by the locking projection 19a engaging with the locking recess 18b on the outer surface of the protective cylinder portion 18. A connection portion between the housing 3 and the optical fiber cable 21 is surrounded by the coupling 2, the protective cylinder portion 18, and the boot 17.

  FIG. 3 is a sectional view showing an optical fiber cable with a connector according to the second embodiment of the present invention. FIG. 4 is a perspective view showing the appearance of this optical fiber cable with a connector. FIG. 5 is an exploded perspective view showing the optical fiber cable with a connector. FIG. 6 is a process diagram showing an assembly process of the optical connector, and shows a state before the optical fiber is connected. FIG. 7 is a process diagram showing an assembly process following the previous figure, and shows a state in which optical fibers are connected. FIG. 8 is a process diagram showing an assembly process following the previous figure, and shows a state in which the housing and the optical fiber cable are connected by the reinforcing tube.

As shown in FIGS. 3 to 5, this optical fiber cable with a connector is obtained by assembling an optical connector 30 at the end of an optical fiber cable 21.
The optical connector 30 generally has the same configuration as the optical connector 1 shown in FIG. 1 except that the protective cylinder portion 18 is not provided.
In this optical fiber cable with a connector, the rear end portion of the reinforcing tube 10 is covered with the optical fiber cable 21 and is in close contact with and joined to the outer surface (side surface) of the distal end portion of the outer sheath 24. The reinforcing material 11 is filled from the tube fixing portion 9 to the tip of the optical fiber cable 21.
The boot 17 is attached to the coupling 2 by the locking projection 17 a being locked in the locking hole 2 a of the coupling 2. A connection portion between the housing 3 and the optical fiber cable 21 is surrounded by the coupling 2 and the boot 17. The coupling 2 is preferably formed so as to surround most of the reinforcing tube 10.

Next, a method for assembling the optical connector 30 at the end of the optical fiber cable 21 will be described.
As shown in FIGS. 6 and 7, the optical fiber 22 is led out from the end of the optical fiber cable 21 and the strength member 23 is pulled out, and the front end portion 22a of the optical fiber 22 is fusion-bonded to the rear end portion 12b of the built-in optical fiber 12. To do.
For example, the end portions of the optical fibers 12 and 22 can be fused and connected by heating and butting them together by arc discharge or the like. At this time, since a sufficient space can be secured around the optical fiber connecting portion, a fusion holder using a general-purpose discharge electrode can be used.
The reinforcing tube 10 and the boot 17 are in a state where the optical fiber cable 21 is inserted in advance.

Next, the reinforcing tube 10 is disposed so as to accommodate the fusion splicing portion 15, the strength member 23, and the reinforcing material 11.
When the reinforcing core material is used, the reinforcing core material is inserted into the reinforcing tube 10 from the tube fixing portion 9 to the optical fiber cable 21.
As shown in FIG. 8, the reinforcing tube 10 is heated to a shrinkage temperature or higher to be shrunk. As a result, the front end portion of the reinforcing tube 10 is brought into close contact with and fixed to the outer surface of the tube fixing portion 9. The rear end portion of the reinforcing tube 10 is also in close contact with the outer surface of the outer sheath 24 of the optical fiber cable 21 and is firmly fixed.
At the same time, when the temperature rises above the softening temperature by heating, the reinforcing material 11 softens and flows so as to spread throughout the reinforcing material 11, and the outer sheath 24 of the end of the optical fiber cable 21 from the surface of the tube fixing portion 9, that is, the outer surface. Fill to the surface. When the heating is stopped and the temperature becomes lower than the softening temperature, the reinforcing material 11 is solidified. The strength member 23 is embedded and fixed in the reinforcing material 11. Thereby, the housing 3 and the optical fiber cable 21 are connected.

  Next, the housing 3 is inserted into the coupling 2 and the boot 17 is attached to the coupling 2 to obtain the optical fiber cable with a connector shown in FIGS.

In the above optical fiber cable with a connector, the housing 3 and the optical fiber cable 21 are covered by the reinforcing tube 10 and the reinforcing tube 11 is filled with the reinforcing material 11. 3 and the optical fiber cable 21 can be given sufficient strength.
In addition, since the strength member 23 drawn out from the end of the optical fiber cable 21 is fixed in the reinforcing member 11, not only the end treatment of the strength member 23 is simplified, but the strength can be further increased.
Furthermore, the end portion of the housing 3 and the end portion of the optical fiber cable 21 can be integrally bonded by the reinforcing member 11 such as a hot melt adhesive with a reinforcing core vertically, and the mechanical strength of the connecting portion is very high. Are better. In particular, by forming the concavo-convex portion 16 in the housing 3, a strong adhesive fixing force can be secured.
Therefore, even when a large tensile force is applied to the connection portion, the fusion splicing portion 15 is not damaged or the optical fiber is not cut.
Further, since the fusion splicing portion 15 is covered with the reinforcing material 11 and the reinforcing tube 10, the fusion splicing portion 15 can be protected.
In this optical fiber cable with a connector, the fusion splicing portion 15 is disposed in the reinforcing tube 10 provided outside the housing 3, so that the fusion splicing portion is housed in the housing, compared to the structure in which the fusion splicing portion is accommodated in the housing. Since the size can be reduced and the overall length can be shortened, the entire connector portion at the tip of the optical fiber cable 21 can be reduced in size.
Therefore, the optical fiber can be accommodated in a narrow storage space such as an optical junction box or a rosette without applying an excessive bending to the optical fiber.
Furthermore, since a general-purpose fusing holder can be diverted to the fusing work, the fusing work becomes easier as compared with the structure in which the fusion splicing portion is arranged in the ferrule.
Another advantage of the connector-equipped optical fiber cable is that the number of parts is small and the assembly work is easy.

  9 is a cross-sectional view showing an optical connector according to an embodiment of the present invention, FIG. 10 is a cross-sectional view taken along line AA in FIG. 9, and FIG. 11 is a cross-sectional view taken along line BB in FIG. In the figure, reference numeral 31 denotes an optical connector, which is a bare optical fiber 32a of a built-in optical fiber 32 (hereinafter simply referred to as an optical fiber 32) of an optical connector that has been cut in advance with a predetermined lead length and a bare optical fiber 33a of an optical fiber cord 33. Is fusion-bonded at the fusion-bonding portion 34.

  Reference numeral 35 denotes a ferrule containing the optical fiber 32 of the optical connector, 36 denotes a connector housing for fixing the ferrule 35, 37 denotes a stop ring abutted against one end portion of the connector housing 36, and 38 denotes one end portion of the stop ring 37. A cylindrical reinforcing tube covering the stop ring 37 in close contact with the flange 37a, 39 is a hot melt resin (reinforcing material) filled between the reinforcing tube 38 and the fusion splicing portion 34, and 40 is an optical connector. Reinforcing core material disposed substantially parallel to the axes of the optical fiber 32 and the optical fiber cord 33 and having one end in close contact with the stop ring 37, 41 is a tensile body covering the periphery of the bare fibers 32 a and 33 a including the fusion splicing portion 34. , 42 are boots made of a cylindrical casing.

A plurality of grooves 51 are formed in the outer circumferential portion of the stop ring 37 in parallel with the circumferential direction, and these grooves 51 are filled with a hot melt resin 39.
The width, depth, interval, and the like of these grooves 51 may be any strength that can withstand the stress in the longitudinal direction when the stop ring 37 is covered with the reinforcing tube 38, but the strength is usually the highest. Is set to For example, when the diameter of the stop ring 37 is 4 mm, the length is 8 mm, and the length of the reinforcing tube 38 is 34 mm, the width of the groove 51 is 2 mm, the depth is 2 mm, and the interval is 1.5 mm.

  On the other hand, the optical fiber 32 of the optical connector is fixed to the tip of the stop ring 37 with an adhesive or the like. Thus, the position of the optical fiber 32 of the optical connector can be fixed by fixing the stop ring 37 and the optical fiber 32 of the optical connector with an adhesive or the like. Therefore, there is no possibility that the optical fiber 32 of the optical connector protrudes outside the stop ring 37 when an external force is applied to the optical fiber 32 of the optical connector, which was a drawback of the prior art.

The reinforcing tube 38 is made of a heat-shrinkable resin that shrinks when heated to a predetermined temperature or higher. For example, a resin such as polyethylene (shrinkage temperature: 100 to 120 ° C.) is preferably used. The reinforcing tube 38 covers the tip portion from the flange 37 a of the stop ring 37.
The hot melt resin 39 is melted and deformed into a desired shape by heating the cured resin composition as a raw material or precursor to a predetermined temperature or higher, and then cooled to a desired temperature lower than the predetermined temperature. In view of workability and the like, a resin that melts at a temperature that approximates the shrinkage temperature of the reinforcing tube 38 is preferable. As such a resin, EVA resin (melting temperature: 90 to 100 ° C.) or the like is preferably used.

The reinforcing core member 40 is, for example, a rod-shaped strength member made of stainless steel such as SUS304, and the tension applied to the bare optical fibers 32a and 33a including the fusion splicing portion 34 from the outside is reduced. This prevents the optical fiber from being bent or bent.
The tensile body 41 is made of, for example, a fiber rich in tensile strength such as an aramid fiber, and when the heat-shrinking of the reinforcing tube 38 and the hot-melt resin 39 is cured, the fusion splicing portion 34 and the bare optical fibers 32a in the peripheral portion thereof This is for relaxing the stress applied to 33a and protecting them.

FIG. 12 shows a breakage of the optical fiber when the length (aramide fiber length) from the core wire outlet portion 33b of the optical fiber cord 33 to the tip of the aramid fiber when an aramid fiber is used for the strength member 41 is changed. It is a figure which shows intensity | strength (kgf).
According to FIG. 12, as long as the aramid fiber does not reach the stop ring, the longer the aramid fiber, the stronger the tendency to break. However, when the stop ring is reached, the strength decreases, so a preferred aramid The fiber length is about 8 mm to 20 mm, and the more preferable aramid fiber length is about 20 mm.

Next, a method for producing the optical connector 31 will be described.
First, as shown in FIG. 13, one end face (connection end face) of the optical fiber 32 fixed in advance to the central through hole (optical fiber introduction hole) of the ferrule 35 of the optical connector is polished together with the ferrule. The coating of the other end of this optical fiber 32 (the end opposite to the connection end face) is peeled to form a bare optical fiber 32a, and this bare optical fiber 32a is cut into a predetermined lead length for performing fusion splicing work. To do.

Further, as shown in FIG. 14, a reinforcing core member 40 is disposed on the inner peripheral surface of the reinforcing tube 38 in parallel with the axis, and a hot melt resin 61 is applied or formed on the inner peripheral surface of the reinforcing tube 38 including the reinforcing core member 40. To do. When the hot melt resin 61 can be molded into a predetermined shape, the molded body may be fitted.
On the other hand, the coating at one end of the optical fiber cord 33 is peeled off to expose the optical fiber core wire 62 and the tensile body 41, and the end portion of the optical fiber core wire 62 is exposed to form a bare optical fiber 33a. Next, as shown in FIG. 15, the optical fiber cord 33 is inserted into the reinforcing tube 38.

Next, as shown in FIG. 16, the discharge electrode rods 63 and 63 of the existing fusion splicer are arranged to face each other at a predetermined interval, and holders 64 and 65 for enabling mounting to the fusion splicer are provided. The ferrule 35, the connector housing 36, and the stop ring 37 are fixed at predetermined positions of the holder 64, and the bare optical fiber 32a of the optical fiber 32 of the optical connector is placed in the V groove 66 of the fusion splicer. The fiber 32a is positioned.
Further, the reinforcing tube 38 and the optical fiber cord 33 are fixed at predetermined positions of the holder 65, and the bare optical fiber 33a is positioned.

Next, the holders 64 and 65 are disposed opposite to each other with the discharge electrode rods 63 and 63 interposed therebetween, but the bare optical fibers 32a and 33a are butted against each other, and a predetermined high voltage is applied to the discharge electrode rods 63 and 63 so Make a fusion splice.
As a result, the bare optical fiber 32 a of the optical fiber 32 of the optical connector and the bare optical fiber 33 a of the optical fiber cord 33 are fused and connected by the fusion splicing portion 34.

Next, as shown in FIGS. 17 to 19, the reinforcing tube 38 is moved to a position surrounding the fusion splicing portion 34 and the bare optical fibers 32 a and 33 a, and the reinforcing tube 38 is brought into contact with the flange 37 a of the stop ring 37. Let Here, the length can be easily managed by bringing the reinforcing tube 38 into contact with the flange 37a.
Next, using a heater, the temperature is maintained at a temperature equal to or higher than the shrinkage temperature of the reinforcing tube 38 and equal to or higher than the melting temperature of the hot-melt resin 61, and simultaneously shrinks the reinforcing tube 38 and simultaneously melts the hot-melt resin 61. As a result, the molten hot melt resin 61 flows in the groove 51 of the stop ring 37 and the reinforcing tube 38 and is densely filled.
At this time, the air in the reinforcing tube 38 is pushed out and no bubbles remain.

Subsequently, it is taken out from the heater and is naturally cooled to a temperature lower than the contraction temperature of the reinforcing tube 38 and the melting temperature of the hot melt resin 61, for example, room temperature (25 ° C.). As a result, as shown in FIG. 20, the reinforcing tube 38 contracts and the hot melt resin 61 is cured, and the reinforcing tube 38, the cured hot melt resin 39, and the stop ring 37 are tightly joined and integrated. .
Finally, the boot 42 is put on to form the optical connector 31 of the present embodiment.

FIG. 21 is a cross-sectional view showing a modified example of the strength member 41 before heat shrinkage according to the present embodiment. This figure is different from FIG. 19 in that the strength member 41 is cross-sectioned at an upper half position from the fusion splicing portion 34. It is the point gathered so that it may become a substantially fan shape.
FIG. 22 is a cross-sectional view showing a modification of the strength member 41 before thermal contraction according to the present embodiment. This figure is different from FIG. 19 in that the strength member 41 is cross-sectioned at a lower half position from the fusion splicing portion 34. It is the point gathered so that it may become a substantially fan shape.
FIG. 23 is a cross-sectional view showing a modified example of the strength member 41 before thermal contraction according to the present embodiment. This figure is different from FIG. 19 in that the strength member 41 is arranged on one side in the longitudinal direction of the fusion splicing portion 34. The points are summarized to have a substantially fan-shaped cross section.

FIG. 24 is a cross-sectional view showing a modification of the strength member 41 before thermal contraction of the present embodiment. This figure is different from FIG. 19 in that the strength member 41 is formed in a substantially circular cross section around the fusion splicing portion 34. The points are randomly arranged so that
As described above, the overall shape and arrangement of the strength member 41 can be variously changed. In any shape and arrangement, the fusion splicing portion 34 and its fusion connection portion 34 and the hot melt resin 61 are cured at the time of thermal contraction of the reinforcing tube 38 and the hot melt resin 61. The stress applied to the bare optical fibers 32a and 33a in the peripheral portion can be relaxed and protected.

FIG. 25 is a side view showing a modified example of the stop ring 37 of the present embodiment. The difference between the stop ring 71 and the stop ring 37 of FIG. 9 is that one groove 51 is formed in the circumferential direction at the tip. Is a point.
For example, when the stop ring 71 has a diameter of 4 mm, a length of 8 mm, and a length of the reinforcing tube 38 of 34 mm, the groove 51 has a width of 2 mm, a depth of 2 mm, and a position from the tip portion of 1.5 mm. .

FIG. 26 is a side view showing a modification of the stop ring 37 of the present embodiment. The difference between this stop ring 81 and the stop ring 37 of FIG. 9 is that two grooves 51 are formed in the circumferential direction at the tip. Is a point.
For example, when the diameter of the stop ring 81 is 4 mm, the length is 8 mm, and the length of the reinforcing tube 38 is 34 mm, the width of the groove 51 is 2 mm, the depth is 2 mm, and the interval is 1.5 mm.

FIG. 27 is a side view showing a modified example of the stop ring 37 of the present embodiment. The difference between the stop ring 91 and the stop ring 37 of FIG. 9 is that one groove 51 is formed in the circumferential direction at the tip portion. Furthermore, a spiral groove 92 is formed in the body part.
In this stop ring 91, by having the circumferential groove 51 and the spiral groove 92, the coefficient of friction between the stop ring 91 and the reinforcing tube 38 is further increased, and the tensile breaking strength is further improved. Become.

FIG. 28 is a side view showing a modified example of the stop ring 37 of the present embodiment. The difference of the stop ring 101 from the stop ring 37 of FIG. 9 is that one groove 51 is formed in the circumferential direction at the tip portion. Furthermore, a concave portion 102 having a circular arc shape and a circular opening is formed vertically and horizontally on the outer peripheral surface of the body portion.
In this stop ring 101, by having the circumferential groove 51 and the concave portion 102 of the body part, the coefficient of friction between the stop ring 101 and the reinforcing tube 38 is further increased, and the tensile breaking strength is further improved. Become.

FIG. 29 is a side view showing a modified example of the stop ring 37 of the present embodiment. The difference between the stop ring 111 and the stop ring 37 of FIG. 9 is that one groove 51 is formed in the circumferential direction at the tip portion. A plurality of rows of recesses 102 having a circular arc shape and circular openings are formed along the axial direction on the outer peripheral surface of the body portion. Further, a rectangular cross section and a triangular opening are formed between the rows of the recesses 102. The recess 112 is formed in a plurality of rows along the axial direction.
The stop ring 111 has the circumferential groove 51 and the concave portions 102 and 112 of the body portion, whereby the coefficient of friction between the stop ring 111 and the reinforcing tube 38 is further increased, and the tensile breaking strength is further improved. It will be.

  As described above, according to the optical connector 31 of the present embodiment, the fusion splicing portion 34 and the bare optical fibers 32 a and 33 a are covered with the reinforcing tube 38, and the reinforcing tube 38 and the fusion splicing portion 34 are between. The hot melt resin 39 hardened to the inside is closely packed, and the reinforcing core member 40 is disposed in the reinforcing tube 38 in parallel to the axis of the optical fiber. It can be surely fixed without any gaps. In addition, handling is easy and manufacturing costs can be reduced.

  In addition, since the reinforcing tube 38 is contracted and the hot melt resin 61 is melted at the same time as it is held at a temperature equal to or higher than the contraction temperature of the reinforcing tube 38 and the melting temperature of the hot melt resin 61, the fusion splicing part 34 of the optical fiber is melted. Further, the reinforcing tube 38, the cured hot melt resin 39, and the reinforcing core member 40 can be densely integrated.

In this embodiment, after the reinforcing tube 38 is brought into contact with the flange 37a of the stop ring 37, the reinforcing tube 38 is contracted and joined and integrated with the cured resin 39 and the stop ring 37. It is good also as a structure which provided the space | interval between the flange 37a of the ring 37. FIG.
Further, the shape and number of the groove 51 of the stop ring, the pitch and depth of the spiral groove 92, the shape, size, number, etc. of the recesses 102 and 112 can be appropriately changed according to need. It is not limited to 29.
In the present embodiment, the concave portions 102 and 112 are used. However, the same effect can be obtained even if the concave portions 102 and 112 are replaced with convex portions.
In the present invention, the optical fiber cable may be an optical fiber cord.

It is sectional drawing which shows the optical fiber cable with a connector which is one Embodiment of this invention. It is a perspective view which shows the optical fiber cable with a connector shown to a previous figure. It is sectional drawing which shows the optical fiber cable with a connector which is one Embodiment of this invention. It is a perspective view which shows the optical fiber cable with a connector shown in FIG. It is a disassembled perspective view which shows the optical fiber cable with a connector shown in FIG. It is process drawing which shows the assembly process of the optical connector shown in FIG. 3, and shows the state before connecting an optical fiber. It is process drawing which shows the assembly process following a previous figure, and shows the state which connected the optical fiber. It is process drawing which shows the assembly process following a previous figure, and shows the state which mounted | wore the reinforcement tube. It is sectional drawing which shows the optical connector of one Embodiment of this invention. It is sectional drawing which follows the AA line of FIG. It is sectional drawing which follows the BB line of FIG. It is a figure which shows the relationship between the aramid fiber length and the breaking strength of an optical fiber. It is process drawing which shows the manufacturing method of the optical connector of one Embodiment of this invention. It is process drawing which shows the manufacturing method of the optical connector of one Embodiment of this invention. It is process drawing which shows the manufacturing method of the optical connector of one Embodiment of this invention. It is process drawing which shows the manufacturing method of the optical connector of one Embodiment of this invention. It is process drawing which shows the manufacturing method of the optical connector of one Embodiment of this invention. It is sectional drawing which follows the CC line of FIG. It is sectional drawing which follows the DD line | wire of FIG. It is process drawing which shows the manufacturing method of the optical connector of one Embodiment of this invention. It is sectional drawing which shows the modification of the tensile strength body before heat shrink of one Embodiment of this invention. It is sectional drawing which shows the modification of the tensile strength body before heat shrink of one Embodiment of this invention. It is sectional drawing which shows the modification of the tensile strength body before heat shrink of one Embodiment of this invention. It is sectional drawing which shows the modification of the tensile strength body before heat shrink of one Embodiment of this invention. It is a side view which shows the modification of the stop ring of one Embodiment of this invention. It is a side view which shows the modification of the stop ring of one Embodiment of this invention. It is a side view which shows the modification of the stop ring of one Embodiment of this invention. It is a side view which shows the modification of the stop ring of one Embodiment of this invention. It is a side view which shows the modification of the stop ring of one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 30 ... Optical connector, 2 ... Coupling, 3 ... Housing, 4 ... Ferrule, 5 ... Coil spring (biasing means), 6 ... Plug frame, 7 ... Stop ring, 8 ... main body, 9 ... tube fixing part, 9a ... annular convex part, 10 ... reinforcing tube, 11 ... reinforcing material, 12 ... built-in optical fiber, 13 ... Capillary part, 13a ... Connection end face, 13b ... Rear end part of capillary part, 14 ... Flange part, 15 ... Fusion splicing part, 21 ... Optical fiber cable, 22 ..Optical fiber, 23 ... Strength, 31 ... Optical connector, 32 ... Optical fiber of optical connector, 32a ... Nude optical fiber, 33 ... Optical fiber cord, 33a ... Nude Optical fiber, 34 ... fusion splicing part, 35 ... 36 ... Connector housing, 37 ... Stop ring, 38 ... Reinforcement tube, 39 ... Hardened hot melt resin (reinforcement material), 40 ... Reinforcement core, 41 ... Strength member , 42 ... boot, 51 ... groove, 61 ... hot melt resin, 62 ... optical fiber core wire, 63 ... discharge electrode rod, 64, 65 ... holder, 66 ... V-groove, 71, 81, 91 ... stop ring, 92 ... spiral groove, 101 ... stop ring, 102 ... recess, 111 ... stop ring, 112 ... recess.

Claims (15)

Connector-attached light in which an optical connector (1) is assembled to the end of an optical fiber cable (21) in which an optical fiber (22) and a tensile body (23) extending along the longitudinal direction of the optical fiber are integrated. A fiber cable,
The optical connector is attached to bias the housing (3), a ferrule (4) which is movable in longitudinal direction within said housing, said ferrule taking a reaction force to the housing (3) to the front Force means (5) ,
The built-in optical fiber (12 ) inserted in the ferrule extends rearward through a through hole provided in the rear end (9) of the housing, and the extended built-in optical fiber (12) The rear end portion (12b) is fusion spliced to the front end portion (22a) of the optical fiber (22) led out to the optical fiber cable end,
The housing and the optical fiber cable are connected by a heat-shrinkable reinforcing tube (10) that accommodates the fusion splice (15),
The reinforcing tube is put on and fixed to each of the rear end portion of the housing and the outer front end portion of the optical fiber cable, and the rear end portion of the housing and the outer front end of the optical fiber cable in the reinforcing tube. A reinforcing material (11) made of a thermoplastic resin is filled between the parts,
The strength member drawn out from the end of the optical fiber cable extends along the longitudinal direction of the optical fiber (22) and the built-in optical fiber (12), and the front end thereof is on the front side of the fusion splicing point. An optical fiber cable with a connector, wherein the optical fiber cable with a connector is fixed in the reinforcing member in the reinforcing tube in a state of being disposed at a position not reaching the rear end of the housing . 2. The optical fiber with a connector according to claim 1, wherein a reinforcing core member extending from a front side of a rear end of the housing to a rear side of a front end of the outer cover of the optical fiber cable is provided in the reinforcing tube. cable. The optical fiber cable with a connector according to claim 1 or 2, wherein the through hole provided in the rear end (9) of the housing has an inner diameter substantially equal to an outer diameter of the built-in optical fiber (12). . The coating of the built-in optical fiber (12) and the optical fiber (22) is removed in the vicinity of the fusion splicing point,
The said tension body pulled out from the said optical fiber cable terminal is fixed in the state which has arrange | positioned the front end in the position which has not removed the coating | coated of the said built-in optical fiber (12) . 4. An optical fiber cable with a connector according to claim 1. One or more annular protrusions (9a) are formed on the outer surface of the housing,
The optical fiber cable with a connector according to any one of claims 1 to 4, wherein the reinforcing tube is fixed to the housing at the annular convex portion. The ferrule includes a capillary part (13) having a joining end surface (13a) at a tip, and a flange part (14) formed at a rear end part (13b) of the capillary part,
The optical fiber cable with a connector according to any one of claims 1 to 5, wherein the flange portion is located at a rear end portion of the ferrule.   The optical fiber cable with a connector according to any one of claims 1 to 6, wherein a protective cylinder portion (18) capable of accommodating at least a part of the reinforcing tube is provided in the housing. . A method of assembling an optical connector (1) at a terminal of an optical fiber cable (21) in which an optical fiber (22) and a tensile body (23) extending along the longitudinal direction of the optical fiber are integrated. ,
The optical connector is attached to bias the housing (3), a ferrule (4) which is movable in longitudinal direction within said housing, said ferrule taking a reaction force to the housing (3) to the front Force means (5) ,
The built-in optical fiber (12 ) inserted in the ferrule extends rearward through a through hole provided in the rear end (9) of the housing,
The rear end portion (12b) of the extended built-in optical fiber (12) is fusion spliced to the front end portion (22a) of the optical fiber (22) led out to the optical fiber cable terminal,
A heat-shrinkable reinforcing tube (10) is disposed so that the fusion splicing portion (15) is accommodated, and a reinforcing material (11) made of a thermoplastic resin is placed in the reinforcing tube,
By heating and shrinking the reinforcing tube,
The reinforcing tube is put on each of the rear end portion of the housing and the outer front end portion of the optical fiber cable, and the rear end portion of the housing and the outer front end portion of the optical fiber cable in the reinforcing tube are fixed. The reinforcing material (11) made of a thermoplastic resin is filled between
The strength member drawn out from the end of the optical fiber cable extends along the longitudinal direction of the optical fiber (22) and the built-in optical fiber (12), and the front end thereof is the front side of the fusion splicing point. The housing and the optical fiber cable are connected by the reinforcing tube so as to be fixed in the reinforcing material in the reinforcing tube in a state where the housing is disposed at a position not reaching the rear end of the housing. An optical connector assembly method. A built-in optical fiber is previously passed through the ferrule of the optical connector, and the end of the built-in optical fiber opposite to the connection end face of the ferrule and the optical fiber of the optical fiber cord that is led out are fused and fused. Cover the connecting part and the outer periphery in the vicinity with a reinforcing tube containing a reinforcing material made of thermoplastic resin and a reinforcing core in advance, and then raise the reinforcing tube to a predetermined temperature with a heater to cause heat shrinkage. In the connection method for protecting the fiber fusion splicing portion and the vicinity thereof,
The ferrule is provided in the housing of the optical connector so as to be movable in the front-rear direction, and is biased forward by a biasing means that takes a reaction force on the stop ring of the optical connector,
The built-in optical fiber extends rearward through a through hole provided in a rear end portion of the stop ring of the optical connector;
The reinforcing tube and the reinforcing core material are disposed on the outer periphery of the stop ring of the optical connector, and the reinforcing material dissolved by heat when the reinforcing tube is heated and contracted is left at room temperature, and then the stop ring and the reinforcing core material And interposing and fixing the reinforcing tube in the boot of the optical connector,
The reinforcing tube is placed on each of the rear end portion of the stop ring and the outer front end portion of the optical fiber cord, and the reinforcing member is fixed to the rear end portion of the stop ring in the reinforcing tube and the Fill between the front end of the outer sheath of the optical fiber cord,
The tensile body led out from the end of the optical fiber cord extends along the longitudinal direction of the optical fiber of the optical fiber cord and the built-in optical fiber, and is disposed in the reinforcing tube and fixed to the reinforcing material. ,
The method of connecting an optical fiber and an optical fiber cord of an optical connector characterized in that the length of the strength member is a length in which the front end is ahead of the fusion splicing point and does not reach the rear end of the stop ring. .   10. The method of connecting an optical fiber and an optical fiber cord of an optical connector according to claim 9, wherein the reinforcing core material in the reinforcing tube reaches the stop ring and overlaps.   The optical fiber of the optical connector and the optical fiber cord according to claim 9 or 10, wherein the built-in optical fiber previously connected to the ferrule of the optical connector is fixed with an adhesive or the like in the stop ring. Connection method.   On the outer peripheral surface of the stop ring, there is one concave, convex, or concave / convex shape of a circular shape, an elliptical shape, a polygonal shape, a circumferential direction, a straight line in the longitudinal direction, a spiral shape, a curved line, a net shape, or a combined shape. The method for connecting an optical fiber of an optical connector and an optical fiber cord according to any one of claims 9 to 11, wherein two or more are engraved.   An optical fiber and an optical fiber cord connection part of an optical connector produced by the optical fiber and optical fiber cord connection method according to any one of claims 9 to 12. A built-in optical fiber is previously passed through the ferrule of the optical connector,
The ferrule is provided in the housing of the optical connector so as to be movable in the front-rear direction, and is biased forward by a biasing means that takes a reaction force on the stop ring of the optical connector,
The built-in optical fiber extends rearward through a through hole provided in a rear end portion of the stop ring of the optical connector, and the end of the built-in optical fiber opposite to the connection end surface of the ferrule A spliced optical fiber cord,
A heat-shrinkable reinforcing tube containing a reinforcing material made of a thermoplastic resin and a reinforcing core material is put on the outer periphery of the fusion splicing portion and the vicinity thereof,
The reinforcing tube is formed from the stop ring of the optical connector to the optical fiber cord,
The reinforcing material is fixedly interposed between the stop ring and the reinforcing core material,
The reinforcing tube is placed on each of the rear end portion of the stop ring and the front end portion of the outer cover of the optical fiber cord, and the reinforcing member is fixed to the rear end portion of the stop ring in the reinforcing tube. And between the front end portion of the outer sheath of the optical fiber cord,
The tensile body led out from the end of the optical fiber cord extends along the longitudinal direction of the optical fiber of the optical fiber cord and the built-in optical fiber, and is disposed in the reinforcing tube and fixed to the reinforcing material. ,
An optical fiber cord with a connector, wherein a length of the tensile body is such that a front end thereof is a front side of the fusion splicing point and does not reach a rear end portion of a stop ring . A built-in optical fiber is previously passed through the ferrule of the optical connector,
The ferrule is provided in the housing of the optical connector so as to be movable in the front-rear direction, and is biased forward by a biasing means that takes a reaction force on the stop ring of the optical connector,
The built-in optical fiber extends rearward through a through hole provided in a rear end portion of the stop ring of the optical connector, and the end of the built-in optical fiber opposite to the connection end surface of the ferrule Can be fusion spliced to the optical fiber of the optical fiber cord,
A heat-shrinkable reinforcing tube containing a reinforcing material made of a thermoplastic resin and a reinforcing core material can be put on the outer periphery of the fusion splicing part and its vicinity,
The reinforcing tube can be formed from a stop ring of the optical connector to the optical fiber cord,
The reinforcing material can be fixedly interposed between the stop ring and the reinforcing core material,
The reinforcing tube is placed on each of the rear end portion of the stop ring and the front end portion of the outer cover of the optical fiber cord, and the reinforcing member is fixed to the rear end portion of the stop ring in the reinforcing tube. And between the front end portion of the outer sheath of the optical fiber cord,
The tensile body led out from the end of the optical fiber cord extends along the longitudinal direction of the optical fiber of the optical fiber cord and the built-in optical fiber, and is disposed in the reinforcing tube and fixed to the reinforcing material. ,
The length of the tensile body is an optical connector characterized in that its front end is in front of the fusion splicing point and does not reach the rear end of the stop ring .

Images