JP5276905B2 - Optical fiber with connector and method of assembling optical connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical connector adaptable to a plurality of types of optical fibers of different diameters. <P>SOLUTION: This optical connector 10 can be assembled at the tips of a first optical fiber and a second optical fiber 18B thinner than it. The optical connector has a ferrule 1 and a holding section 2 disposed on the back end side of the ferrule 1. The holding section 2 has fixable holding bodies 12a and 12c for holding a coating section of the first optical fiber. The holding bodies 12a and 12c can be fixed across the second optical fiber 18B via a spacer tube 19 covering at least a part of the second optical fiber 18B. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

The present invention relates to an optical fiber with a connector , and more particularly to an optical fiber with a connector using an optical connector of a field assembly type that can be assembled at a site outside a factory, and a method for assembling the optical connector .

A field assembly type optical connector is assembled at the tip of an optical fiber such as an optical fiber core wire (see, for example, Patent Document 1).
JP 2007-121861 A

The optical connector has a structure corresponding to the type of the target optical fiber, and it is necessary to select an optical connector corresponding to the target, and a versatile one is desired.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical fiber with a connector that can handle a plurality of types of optical fibers and a method for assembling the optical connector .

The present invention is an optical fiber with a connector in which an optical connector that can be assembled at the tip of a first optical fiber and a second optical fiber having a diameter smaller than that of the first optical fiber is attached to a terminal. A sandwiching portion provided on an end side, the sandwiching portion having a sandwiching body that can be fixed by sandwiching the covering portion of the first optical fiber, and the sandwiching body is formed of the second optical fiber. Provided is an optical fiber with a connector which is fixed by sandwiching the second optical fiber through a spacer tube which is at least partially covered.
It is preferable that the sandwiching portion can sandwich the spacer tube or the covering portion in the sandwiching body by spring elasticity.
The outer diameter of the first optical fiber can be 0.9 mm, and the outer diameter of the second optical fiber can be 0.25 mm.
A protective tube through which the second optical fiber inserted through the spacer tube is inserted can be attached to the rear end of the spacer tube, and the inner diameter of the protective tube is larger than the outer diameter of the second optical fiber. It is preferable.

The present invention is a method of assembling a second optical fiber having a diameter smaller than that of the first optical fiber into an optical connector that can be assembled at the tip of the first optical fiber, the optical connector comprising: an optical ferrule; A holding portion provided on a rear end side of the optical ferrule, and the holding portion has a holding body that can be fixed by holding the covering portion of the first optical fiber, and the second optical fiber. At least a part of the spacer is covered with a spacer tube, the second optical fiber is inserted into the optical connector and connected to the optical fiber in the optical connector, and the second body is interposed by the sandwiching body through the spacer tube. Provided is an optical connector assembling method for sandwiching an optical fiber and fixing the second optical fiber to the sandwiching portion.

The optical connector of the present invention includes a sandwiching portion that can be fixed by sandwiching the covering portion of the first optical fiber and that can be fixed by sandwiching the second optical fiber via the spacer tube. Therefore, it is applicable to a plurality of types of optical fibers having different diameters.
According to the optical connector assembling method of the present invention, it is possible to easily assemble the optical connector even on the second optical fiber having a relatively small diameter.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing an optical connector 10 according to an embodiment of the present invention.
The optical connector 10 is generally called a field assembly type optical connector. This type of optical connector is used when connecting a short optical fiber bonded and fixed to an optical ferrule in a factory and an optical fiber extracted from an optical fiber cable or the like at a connection site such as a user's house. In this type of optical connector, as a method of connecting optical fibers, a method of pressing the vicinity of the connection portion of both optical fibers with a fixing member and mechanically fixing the connection portion is employed.
FIG. 2 shows the optical connector 10 before assembly. FIG. 3 is a side view showing the main part of the stop ring 4. FIG. 4 is an exploded perspective view showing the clamping unit 2. 5 and 6 are cross-sectional views showing the sandwiching portion 2.
In the following description, the left side in FIG. 1 may be referred to as the front, and the right side may be referred to as the rear.

As shown in FIG. 1, the optical connector 10 includes an optical ferrule 1 (hereinafter simply referred to as a ferrule), a clamping portion 2 provided on the rear end side of the ferrule 1, a plug frame 3 that accommodates the clamping portion 2, A stop ring 4 attached to the plug frame 3, an urging means 5 provided in the stop ring 4, and a coupling 6 provided outside the plug frame 3 are provided. Reference numeral 7 denotes a boot portion attached to the rear end of the stop ring 4.
The plug frame 3 and the stop ring 4 constitute a housing 8 that accommodates the clamping part 2.

An optical fiber introduction hole 1b is formed in the ferrule 1 along the central axis, and a built-in optical fiber 11 (such as a bare optical fiber) is inserted and fixed in the optical fiber introduction hole 1b. The front end of the built-in optical fiber 11 is exposed at the front end surface 1 a of the ferrule 1, the rear end protrudes from the rear end of the ferrule 1, and the protruding portion is disposed in the holding part 2.
The ferrule 1 can be formed of ceramics such as zirconia or glass, for example.

As shown in FIG. 4, the sandwiching unit 2 is a clamp unit including a sandwiching body unit 12 and a clamp spring 13 that holds the sandwiching body unit 12.
The sandwiching unit 12 includes a flange portion 12d provided at the rear end portion of the ferrule 1, a base portion 12a (base-side sandwiching body) extending rearward from the flange portion 12d, and two pieces disposed on the base portion 12a. It consists of lid bodies 12b and 12c (lid side clamping body), and an optical fiber can be sandwiched and fixed between the base 12a and the lid bodies 12b and 12c by the elasticity of the clamp spring 13.

The base 12a has a substantially semicircular cross section, a substantially triangular cross section, etc., can be formed integrally with the flange portion 7d, and can be made of metal, plastic, or the like.
The lid body 12b and the lid body 12c have a substantially semicircular cross section, a substantially triangular cross section, etc., and can be made of plastic, metal, etc., and are arranged side by side on the base 12a. The first lid 12b is disposed in front of the second lid 12c, that is, on the ferrule 1 side.

An alignment mechanism 15 is formed in the sandwiching unit 12. The alignment mechanism 15 is a groove formed in the inner surface of the base 12a and the inner surfaces of the lids 12b and 12c, and a covering grip 15a formed in the rear end of the base 12a and the rear of the lid 12c. And a centering portion 15b formed on the ferrule 1 side of the portion 15a.
The alignment portion 15b is narrower than the guide portion 15a, and aligns the built-in optical fiber 11 and the distal end portion 18a of the optical fiber 18 between the base portion 12a and the first lid body 12b. The butt connection is made through a refractive index matching agent.
The covering grip 15a can fix the covering 18b of the optical fiber 18 by sandwiching it between the second lid 12c and the base 12a.

The clamp spring 13 is a means for applying a clamping force to the sandwiching unit 12 and is a metal plate having a C-shaped cross section in the illustrated example.
The distal end portion 18a is a bare optical fiber that is led out from the optical fiber 18 that is a coated optical fiber such as an optical fiber core or an optical fiber. The covering portion 18b is a covering made of synthetic resin or the like.

When the optical connector 10 is connected to another optical connector, the biasing means 5 gives the ferrule 1 a butting force with the counterpart optical connector.
The biasing means 5 is disposed between the rear end of the sandwiching portion 2 and the stop ring 4 and biases the sandwiching portion 2 and the ferrule 1 forward by taking a reaction force on the stop ring 4. As the biasing means 5, a coil spring is suitable.

As shown in FIGS. 2 and 3, the stop ring 4 includes a rectangular parallelepiped main body portion 20, a front extension portion 21 extending from the main body portion 20 into the plug frame 3, and a rear end portion of the main body portion 20 to the rear. And a fixed portion 22 that extends.
The fixed portion 22 includes a cylindrical tube portion 23 and an extended tube portion 24 extending rearward from the rear end.
A screw portion 25 is formed on the outer peripheral surface of the cylindrical portion 23.
The extending cylinder portion 24 is formed in a cylindrical shape having a smaller diameter than the fixed portion 22, that is, a smaller outer diameter.

  The boot portion 7 is made of a relatively soft synthetic resin such as rubber, and includes a cylindrical mounting portion 16 and an extending cylindrical portion 17 extending from the rear end. The mounting portion 16 can be locked in a state where it is covered with the cylindrical portion 23 of the fixing portion 22 due to its elasticity.

  The basic structure of the optical connector 10 includes an SC type optical connector (SC: Single fiber Coupling optical fiber connector; F04 type optical connector (optical connector plug) established by JIS C 5973), an SC2 type optical connector, etc. The structure can be adopted.

The covering gripping portion 15a of the sandwiching portion 2 of the optical connector 10 has a structure in which the covering portion 18b of the optical fiber 18 is sandwiched and fixed between the second lid 12c and the base portion 12a. Cannot be gripped, or the gripping force becomes very weak and the tensile strength is greatly reduced. However, by using the spacer tube 19 described later, it is possible to practically connect a plurality of types of optical fibers having different gripping forces and different outer diameters.
That is, in the present invention, being able to be assembled at the tip means that a state in which the gripping force is strong can be realized.

Hereinafter, the configuration of the optical connector 10 when a plurality of types of optical fibers are used will be described for each type of optical fiber.
First, the case of applying to the first optical fiber 18A will be described. The first optical fiber 18A is an optical fiber having an outer diameter of 0.9 mm, for example.
As the first optical fiber 18A, for example, a strand obtained by applying a silicon coating having an outer diameter of 0.4 mm to a glass optical fiber having an outer diameter of 0.125 mm is coated with a nylon coating having an outer diameter of 0.9 mm. An optical fiber (so-called 0.4 silicon / 0.9 nylon) can be used.
In addition, an optical fiber obtained by coating a glass optical fiber having an outer diameter of 0.125 mm with an ultraviolet curable resin (hereinafter referred to as UV resin) having an outer diameter of 0.25 mm, and polyvinyl chloride having an outer diameter of 0.9 mm (hereinafter referred to as UV resin). An optical fiber (so-called 0.25 UV / 0.9 PVC) coated with a PVC resin) can also be used.
In addition, although various things can be employ | adopted as a coating | covering material, in any case, an outer diameter is 0.9 mm in this example. Since an optical fiber having a diameter of 0.9 mm is standardly used worldwide, an optical connector capable of connecting an optical fiber having a diameter of 0.9 mm is very important.

As shown in FIGS. 4 and 5, the wedge 26 is inserted between the lids 12 b and 12 c of the sandwiching body unit 12 and the base portion 12 a, so that the lid body resists the clamping force of the clamp spring 13. The gap between 12b and 12c and the base 12a is widened.
As shown in FIG. 2, the first optical fiber 18 </ b> A passed through the boot portion 7 is inserted into the insertion hole 22 a of the fixing portion 22 of the stop ring 4.
Further, the distal end portion 18a is inserted from the covering gripping portion 15a of the sandwiching unit 12 and guided to the aligning portion 15b to be butt-connected to the built-in optical fiber 11.
As shown in FIG. 6, when the wedge 26 is pulled out, the optical fiber 11 and the distal end portion 18a are sandwiched between the first lid 12b and the base portion 12a by the clamping force of the clamp spring 13, and the optical fibers 11 and 18A Connection is maintained.

As shown in FIG. 1, at this time, the covering portion 18b of the first optical fiber 18A is sandwiched and fixed between the second lid body 12c and the base portion 12a.
When the boot portion 7 is attached to the cylindrical portion 23 of the fixed portion 22, the assembly of the optical connector 10 shown in FIG.
The optical connector of the present invention can be connected to the optical fiber connector in a state where the wedge is inserted in advance between the base of the sandwiching unit and the lid body and assembled to the optical connector (optical connector with a tool). Can be performed efficiently.

Next, the case where it applies to the 2nd optical fiber 18B which is the optical fiber 18 whose diameter is smaller than the 1st optical fiber 18A is demonstrated. The second optical fiber 18B is an optical fiber having an outer diameter of 0.25 mm, for example.
As the second optical fiber 18B, for example, an optical fiber obtained by coating a glass optical fiber having an outer diameter of 0.125 mm with a UV resin coating having an outer diameter of 0.25 mm can be used.
Since optical fibers with a diameter of 0.25 mm are standardly used worldwide, an optical connector that can connect an optical fiber with a diameter of 0.25 mm is very important.
7 and 8 show the configuration of the optical connector 10 in the case where the second optical fiber 18B is used. In the optical connector 10 of this example, the second optical fiber 18B has a leading end portion 18a that is exposed like the first optical fiber 18A, and a spacer tube 19 is covered on the peripheral surface of the covering portion 18c. Yes.

As shown in FIGS. 8 and 9, the spacer tube 19 is made of a synthetic resin material having flexibility, and the outer diameter of the spacer tube 19 is the second lid in the sandwiching portion 2 in a state of covering the second optical fiber 18B. It is set between the body 12c and the base 12a so that the optical fiber 18B inside the tube 19 can be fixed. For example, the spacer tube 19 can have an outer diameter that is substantially the same as or slightly larger than the outer diameter of the covering portion 18b of the first optical fiber 18A.
The inner diameter of the spacer tube 19 needs to be set so that the second optical fiber 18B does not fall out even if a tensile force is applied to the second optical fiber 18B when the spacer tube 19 is fixed in the holding portion 2. For example, the inner diameter can be substantially the same as or slightly larger than the outer diameter of the second optical fiber 18B.
The outer diameter of the spacer tube 19 is, for example, 0.93 mm, and the inner diameter can be, for example, 0.28 mm.

The spacer tube 19 is attached within a predetermined length from the tip of the covering portion 18c of the second optical fiber 18B.
That is, the spacer tube 19 only needs to be attached to at least a portion of the sandwiching unit 2 that is sandwiched by the sandwiching body unit 12, and the other portions may not be provided. The spacer tube 19 can also be mounted in a range reaching the part outside the optical connector 10.
The shape of the spacer tube 19 is not particularly limited, but the cross section is preferably symmetrical with respect to the central axis.

As shown in FIGS. 8 and 10, a protective tube 27 can be provided at the rear end of the spacer tube 19.
The protective tube 27 includes a connecting cylinder portion 28 that can be attached to the rear end of the spacer tube 19 and a tube main body 29 extending from the rear end.
The connection cylinder part 28 consists of a synthetic resin material etc. which have flexibility, The internal diameter is set so that the spacer tube 19 can be inserted. The inner diameter of the connecting tube portion 28 is preferably substantially equal to the outer diameter of the spacer tube 19, and it is preferable that the spacer tube 19 can be locked to the spacer tube 19 by elasticity when the spacer tube 19 is inserted from the front end side.

  The tube main body 29 is made of a synthetic resin material having flexibility, and the optical fiber 18B can be inserted therethrough. If the inner diameter of the tube main body 29 is set larger than the outer diameter of the optical fiber 18B and a gap is formed between the optical fiber 18B, the optical fiber 18B can easily move within the tube main body 29. The operation of inserting the optical fiber 18B is facilitated.

Next, a method for assembling the optical connector 10 at the tip of the second optical fiber 18B will be described.
As shown in FIGS. 7 and 8, the spacer tube 19 is mounted within a predetermined length from the tip of the covering portion 18c of the second optical fiber 18B, and the connecting tube portion 28 of the protective tube 27 is provided on the rear end side. Install.
This is inserted into the stop ring 4, the tip end portion 18 a is butted and connected to the built-in optical fiber 11 at the alignment portion 15 b, and the wedge 26 is pulled out (see FIG. 6). Thereby, the connection of the optical fibers 11 and 18B is maintained.

At this time, the spacer tube 19 of the second optical fiber 18B is sandwiched and fixed between the second lid 12c and the base 12a. That is, the second optical fiber 18 </ b> B is fixed to the holding unit 2 via the spacer tube 19.
When the boot portion 7 is attached to the cylindrical portion 23 of the fixed portion 22, the assembly of the optical connector 10 shown in FIG. 7 is completed.
Thus, the optical connector 10 can be applied to the second optical fiber 18B having a relatively small diameter by adopting the spacer tube 19.
In addition, when applying to an optical fiber having a diameter smaller than that of the second optical fiber 18B, the spacer can be sandwiched by using a spacer tube thicker than the spacer tube 19 illustrated. In addition, by using a spacer tube having a thickness corresponding to the diameter of the optical fiber, an optical fiber having an arbitrary outer diameter can be fixed by the sandwiching portion 2.

FIG. 11 shows a configuration of the optical connector 10 to which, for example, an optical fiber cord 18C (optical fiber) having an outer diameter of 2 mm is connected.
The optical fiber cord 18C has a structure in which an optical fiber 31 such as an optical fiber core and a tensile body 32 extending in the longitudinal direction of the optical fiber 31 are accommodated in a jacket 33 made of a resin such as polyethylene. Can be illustrated.
As the strength member 32, an aramid fiber is preferably used, but glass fiber, carbon fiber, or the like can also be used.
Optical fiber cords are standardly used worldwide. In the optical fiber cord, an optical fiber having an outer diameter of 0.9 mm is standardly used worldwide. In the illustrated example, the optical fiber 31 built in the optical fiber cord 18C has an outer diameter of 0.9 mm.

In this example, a boot portion 35 is used instead of the boot portion 7.
The boot portion 35 is inserted into the fixing cap 36 that can be fixed to the fixing portion 22 of the stop ring 4, an extending portion 37 that is connected to the rear end side of the fixing cap 36 and extends rearward, and the extending portion 37. And a protective tube 40.
The fixing cap 36 is made of a relatively hard synthetic resin or the like, and includes a cylindrical mounting portion 38 that is screwed to the fixing portion 22 and a connection cylindrical portion 39 that extends rearward from the rear end portion of the mounting portion 38. Have.
On the inner surface of the mounting portion 38, a screw portion 41 that is screwed into the screw portion 25 of the fixing portion 22 is formed.
The connecting tube portion 39 is covered with an extending portion 37 made of a relatively soft synthetic resin such as rubber and is locked by its elasticity.

  As shown in FIG. 11, the fixing cap 36 can be screwed and fixed to the fixing portion 22 with the strength member 32 pulled out from the end of the optical fiber cord 18 </ b> C sandwiched between the fixing portion 22. That is, the tensile strength body 32 can be fixed to the fixing portion 22 by fitting the screw portion 41 of the mounting portion 38 to the screw portion 25 of the fixing portion 22 with the tensile strength body 32 sandwiched therebetween.

Next, a method for assembling the optical connector 10 at the tip of the optical fiber cord 18C will be described.
As shown in FIGS. 11 and 12, the optical fiber 31 is led out from the optical fiber cord 18C and the strength member 32 is pulled out. Further, the tip portion 31a (for example, a bare optical fiber) of the optical fiber 31 is extracted.
The optical fiber 31 is inserted into the stop ring 4, and the leading end 31a is butted and connected to the built-in optical fiber 11 at the aligning portion 15b, and the wedge 26 is pulled out (see FIG. 6). Thereby, the connection of the optical fibers 11 and 31 is maintained.
At this time, the covering portion 31b of the optical fiber 31 is sandwiched and fixed between the second lid body 12c and the base portion 12a.

  Next, as shown in FIG. 12, the fixing cap 36 is screwed to the fixing portion 22 in a state where the strength members 32 are divided into a plurality of bundles and arranged on the outer peripheral surface of the fixing portion 22 as necessary. Thereby, the strength member 32 is sandwiched and fixed between the fixing cap 36 and the fixing portion 22.

When an optical fiber having a smaller diameter (for example, an outer diameter of 0.25 mm) than the optical fiber 31 (an outer diameter of 0.9 mm) is employed for the optical fiber cord 18C, the spacer tube 19 is covered as described above.
However, since the coating of the optical fiber having a diameter of 0.25 mm is different from that used for a general optical fiber cord, the structure of the portion extending from the optical connector 10 is different from that of the optical fiber cord. A structure can be adopted.

As described above, in the optical connector 10, the sandwiching section 2 can be fixed by sandwiching the first optical fiber 18 </ b> A, and the second optical fiber having a diameter smaller than that of the first optical fiber 18 </ b> A is provided via the spacer tube 19. The optical fiber 18B can be sandwiched and fixed.
Furthermore, an optical fiber having an arbitrary diameter can be fixed by using a spacer tube having an inner diameter corresponding to the outer diameter of the optical fiber.
Therefore, it can be applied to a plurality of types of optical fibers having different diameters.

It is sectional drawing which shows the optical connector which is one Embodiment of this invention. It is an optical connector of the state before an assembly. It is a side view which shows the principal part of a stop ring. It is a disassembled perspective view which shows a clamping part. It is sectional drawing which shows a clamping part. It is sectional drawing which shows a clamping part. It is sectional drawing which shows the example which applied the optical connector to the other optical fiber. It is a principal part enlarged view which shows the fixed state of an optical fiber. It is a perspective view which shows a spacer tube. It is a perspective view which shows a protection tube. It is sectional drawing which shows the example which applied the optical connector to the other optical fiber. It is explanatory drawing which shows the assembly process of an optical connector.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ferrule, 2 ... Holding part, 8 ... Housing, 10 ... Optical connector, 12a ... Base part (base part side clamping body), 12c ... Lid body (lid side clamping body) , 13 ... Clamp spring, 18 ... Optical fiber, 18a ... Tip, 18b, 18c ... Cover, 18A, 18B ... Optical fiber (optical fiber core), 18C ... Optical fiber (optical fiber cord), 19 ... spacer tube, 22 ... fixing part, 25 ... screw part, 27 ... protective tube, 32 ... strength member.

Claims (5)

An optical fiber with a connector in which an optical connector that can be assembled at the tip of the first optical fiber (18A) and the second optical fiber (18B) having a smaller diameter than the first optical fiber is assembled to a terminal ,
An optical ferrule (1), and a clamping part (2) provided on the rear end side of the optical ferrule,
The sandwiching portion has a sandwiching body (12a, 12c) that can be fixed by sandwiching the covering portion (18b) of the first optical fiber (18A),
The clamping bearing member is a connector with, characterized in that via a spacer tube (19) which is covered on at least a portion of said second optical fiber (18B) is fixed by sandwiching the second optical fiber Optical fiber (10). 2. The optical fiber with a connector according to claim 1, wherein the sandwiching portion can sandwich the spacer tube or the covering portion with the sandwiching body by elasticity of a spring (13). The optical fiber with a connector according to claim 1 or 2, wherein an outer diameter of the first optical fiber is 0.9 mm, and an outer diameter of the second optical fiber is 0.25 mm. A protective tube (27) through which the second optical fiber (18B) inserted through the spacer tube is inserted can be attached to the rear end of the spacer tube,
The optical fiber with a connector according to any one of claims 1 to 3, wherein an inner diameter of the protective tube is larger than an outer diameter of the second optical fiber (18B). A method of assembling a second optical fiber (18B) having a diameter smaller than that of the first optical fiber into an optical connector that can be assembled at the tip of the first optical fiber (18A),
The optical connector includes an optical ferrule (1) and a holding portion (2) provided on the rear end side of the optical ferrule, and the holding portion includes a covering portion (18b) of the first optical fiber. It has clamping bodies (12a, 12c) that can be clamped and fixed,
At least a part of the second optical fiber is covered with a spacer tube (19), the second optical fiber is inserted into the optical connector, connected to the optical fiber (11) in the optical connector, and the sandwiched A method of assembling an optical connector, comprising: sandwiching the second optical fiber by a body through the spacer tube, and fixing the second optical fiber to the clamping portion.

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