JP5367733B2 - Coating removal member, coating removal member manufacturing method, and optical connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique capable of significantly improving the workability when mounting an optical fiber on an optical connector and facilitating assembling work of the optical connector. <P>SOLUTION: A coating removing member that removes, with insertion work of the optical fiber to be mounted, the coating of an optical fiber is incorporated in an optical connector. The coating removing member has such a configuration that a guide part for guiding a coated optical fiber, a coating removing part for removing the coating of the optical fiber and a connecting part for connecting the guide part to the coating removing part are integrally formed. A naked fiber insertion hole of the coating removing part and a coating fiber insertion hole of the guide part are coaxially located, and a separation distance between an extraction end of a coated fiber insertion hole and an insertion end of the naked fiber insertion hole is not less than 0.1 mm and not more than 0.5 mm. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a coating removal member for removing a coating of an optical fiber, a method for manufacturing the coating removal member, and an optical connector including the coating removal member.

  In recent years, with the spread of FTTH (Fiber To The Home) and the like, a large number of optical communication networks are used in general homes, etc., so that mechanical splice type optical fiber connectors (hereinafter referred to as optical fibers) that can be easily assembled at the connection site such as user homes. Connector) has been developed and put into practical use (for example, Patent Document 1). This mechanical splice optical connector has a short optical fiber (hereinafter referred to as a built-in optical fiber) mounted in advance on a ferrule, and the optical fiber to be connected (hereinafter referred to as a connection optical fiber) is abutted against the built-in optical fiber for connection. It is assembled by doing.

FIG. 16 is a diagram showing a schematic configuration of a general mechanical splice type optical connector (for example, SC connector).
As shown in FIG. 16, the optical connector 5 includes an optical fiber connection portion 50 for connecting a connection optical fiber (not shown) to the built-in optical fiber F1, a frame 61 for housing the optical fiber connection portion 50, a frame A stop ring 62 that fixes the optical fiber connection portion 50 to 61, a coil spring 63 that is interposed between the optical fiber connection portion 50 and the stop ring 62 and biases the optical fiber connection portion 50 in the connection direction, and the like. . A so-called housing is configured by the frame 61 and the stop ring 62, and the tip of the frame 61 serves as an interface with a connection destination (for example, an optical connector).

  The optical fiber connection unit 50 includes a ferrule 51, a base member 52, fiber pressing members 53 and 54, a clamp member 55, and the like. The base member 52 has a flange portion 521 that holds the ferrule 51 on which the built-in optical fiber F1 is mounted in advance, and a fiber fixing groove (for example, V-shaped groove) 522 that holds the connection optical fiber. In the fiber fixing groove 522, a portion protruding from the rear end of the ferrule 51 of the built-in optical fiber F1 and a front end portion of the connection optical fiber are placed.

In the optical fiber connecting portion 50, the built-in optical fiber F1 and the connecting optical fiber are sandwiched by the base member 52 and the fiber pressing members 53 and 54 in a state where the connecting optical fiber is abutted against the built-in optical fiber F1, and the clamp member 55 Fix by energizing. Specifically, after attaching the ferrule 51, the fiber pressing members 53, 54 and the clamp member 55 to the base member 52, the base member 52 and the fiber pressing members 53, 54 are joined by pressing a wedge (not shown). The connecting optical fiber with the surfaces slightly spaced apart and the coating on the tip removed is inserted along the fiber fixing groove 522. Then, the front end of the connection optical fiber is abutted against the rear end of the built-in optical fiber F1, and the wedge is pulled out in this state, so that the built-in optical fiber F1 and the connection optical fiber are connected by the base member 52 and the fiber pressing members 53 and 54. Hold and fix.
Thus, since the optical connector 5 can be easily assembled in a short time, it is suitable as a field assembly type optical connector.

As described above, when attaching the connection optical fiber to the optical connector, in order to align the connection optical fiber and the built-in optical fiber with high accuracy, the connection optical fiber (for example, an optical fiber core with a coating outer diameter of 250 μm) is used. It is necessary to remove the coating on the tip of the wire. Conventionally, with the optical fiber mounting jig held by the connecting optical fiber, an operator removes a predetermined length of the coating from the tip using a dedicated tool and wipes it with alcohol or the like.
However, since the optical fiber from which the coating has been removed (bare optical fiber) is easily damaged, skill is required in the operation for removing the coating and the operation for attaching the connection optical fiber to the optical connector.

  Therefore, the present applicant arranges a coating removing member that removes the coating of the connection optical fiber as the connection optical fiber is inserted along the fiber fixing groove in the optical fiber connection portion of the optical connector, An optical connector that can significantly improve workability when an optical fiber is mounted has been proposed (Japanese Patent Application No. 2010-127235).

Japanese Patent No. 3515677

  In the optical connector described in Japanese Patent Application No. 2010-127235, a guide member for guiding the optical fiber to the coating removal unit is disposed in the front stage of the coating removal member. The optical fiber is directed from the guide member toward the coating removal member. In order to smoothly insert the guide member, the guide member and the sheath removing member must be aligned with high accuracy. That is, although workability at the time of optical fiber mounting is improved, there is room for further improvement because it takes time to assemble the optical connector.

  The present invention has been made to solve the above-described problems, and can significantly improve the workability when attaching an optical fiber to an optical connector, and also provides a coating removal member and a coating removal member that can facilitate assembly work. An object is to provide a manufacturing method and an optical connector.

The invention according to claim 1 is a guide portion having a coated fiber insertion hole for guiding a coated optical fiber;
A coating removal unit that has a bare fiber insertion hole through which the bare fiber portion of the optical fiber from which the coating has been removed can be inserted, and removes the coating of the optical fiber at an end portion on the fiber insertion side that serves as an insertion port for the optical fiber When,
The guide portion and the coating removal portion are arranged such that the bare fiber insertion hole and the coated fiber insertion hole are coaxial, and an insertion end of the coated fiber insertion hole and an insertion end of the bare fiber insertion hole And a plurality of connecting portions that are connected so that the separation distance is 0.1 mm or more and 0.5 mm or less .
The plurality of connecting portions connect the guide portion and the covering removal portion with a part of a side surface so that an open portion is formed between the plurality of connecting portions.
This is a coating removing member.
According to a second aspect of the present invention, in the coating removing member according to the first aspect, a hollow portion is formed on the optical fiber insertion side of the bare fiber insertion hole.

A third aspect of the present invention is the coating removing member according to the first or second aspect , wherein the separation distance is 0.1 mm or more and 0.3 mm or less.

According to a fourth aspect of the present invention, in the coating removal member according to any one of the first to third aspects, the coating removal member is made of a synthetic resin material.

According to a fifth aspect of the present invention, in the coating removal member according to any one of the first to fourth aspects, the outer surface of the end portion on the fiber insertion side of the coating removal portion is 45 with respect to the central axis. It is characterized by being formed at an angle of less than 0 °.

The invention according to claim 6 is the coating removal member according to any one of claims 1 to 5 , wherein the outer surface of the end portion on the fiber insertion side of the coating removal portion is a flat surface, a curved surface, or flat surfaces. Are arranged in a circumferential direction and have a symmetrical shape with respect to the central axis.

  The invention described in claim 7 is a method of manufacturing a coating removal member, wherein the coating removal member according to any one of claims 1 to 6 is molded by injection molding using a mold. .

  According to an eighth aspect of the present invention, in the method for manufacturing a coating removing member according to the seventh aspect, the bare fiber insertion hole and the coated fiber insertion hole are formed by the same core pin.

Invention of Claim 9 is equipped with the coating removal member as described in any one of Claim 1 to 6,
In accordance with the insertion operation of the optical fiber to be mounted, the optical fiber coating is removed by the coating removal unit.

The invention according to claim 10 is the optical connector according to claim 9,
A ferrule fitted with a first optical fiber;
A base member formed with a fiber fixing groove for holding the second optical fiber to be connected and the first optical fiber in a butted state;
A fiber pressing member that contacts the base member and holds the first optical fiber and the second optical fiber with the base member;
A clamp member that urges the fiber pressing member against the base member, and an optical fiber connecting portion having a structure attached to the housing,
The sheath removing member is disposed in the optical fiber connecting portion;
As the second optical fiber is inserted along the fiber fixing groove, the coating of the second optical fiber is removed by the coating removing unit.

  According to the present invention, when the optical fiber is attached to the optical connector, the coating of a predetermined length is removed along with the insertion of the optical fiber, so that workability when attaching the optical fiber to the optical connector is remarkably improved. The In addition, since the coating removal portion and the guide portion are integrally formed with the coating removal member, it is not necessary to align both axes, and the assembly work of the optical connector can be facilitated.

It is a perspective view which shows the principal part structure of the optical fiber connection part of the optical connector which concerns on embodiment. It is a disassembled perspective view which shows the principal part structure of an optical fiber connection part. It is sectional drawing which shows the principal part structure of an optical fiber connection part. It is a perspective view which shows the external appearance shape of a coating removal member. It is a perspective view which shows the external appearance shape of a coating removal member. It is a side view of a coating removal member. It is a top view of a coating removal member. It is AA sectional drawing in FIG. It is an enlarged view of the fiber insertion side of a coating removal part. It is a figure which shows the relationship between taper angle (theta) ₂ of the outer surface of a coating removal part, and the pressing force required for coating removal. It is a disassembled perspective view which shows an example of the metal mold | die for producing a coating removal member. It is a top view which shows the assembly | attachment state of a metal mold | die. It is a figure which shows the modification of the outer surface of a coating | coated removal part. It is a figure which shows the relationship between the separation distance of a coating removal part and a guide part, and the pressing force at the time of coating removal. It is sectional drawing which shows another example of an optical fiber connection part. It is a figure which shows schematic structure of a general mechanical splice type | mold optical connector.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The schematic configuration of the optical connector of the present embodiment is the same as the general configuration shown in FIG. For distinction, the reference numeral of the optical connector according to the embodiment is 1. In other words, the optical connector 1 according to the present embodiment is configured such that an optical fiber connection portion for connecting an optical fiber to be connected (hereinafter referred to as a connection optical fiber) to a built-in optical fiber is attached to the housing. A mechanical splice type optical connector (for example, SC connector). In the present embodiment, since the optical fiber connection portion has a characteristic configuration, the optical fiber connection portion will be described.

1 is a perspective view showing a configuration of a main part of an optical fiber connection portion 10 of an optical connector 1 according to an embodiment, FIG. 2 is an exploded perspective view of the optical fiber connection portion 10, and FIG. 3 is a cross-sectional view of the optical fiber connection portion 10. is there. FIG. 3A shows a state where the connection optical fiber F2 is not attached, and FIG. 3B shows a state where the connection optical fiber F2 is attached.
The connecting optical fiber F2 is, for example, an optical fiber core having a coating outer diameter of 250 μm, which is obtained by applying a 62.5 μm-thick coating (for example, UV resin coating) to a bare optical fiber having an outer diameter of 125 μm.

As shown in FIGS. 1-3, the optical fiber connection part 10 is provided with the ferrule 11, the base member 12, the 1st fiber pressing member 13, the 2nd fiber pressing member 14, the clamp member 15, and the coating | coated removal member 16 grade | etc.,. Composed.
The ferrule 11 is a substantially columnar member made of a ceramic material such as zirconia, for example, and has pores 111 formed along the central axis. A built-in optical fiber F1 such as a bare optical fiber (uncoated optical fiber) or the like is inserted into the pore 111 and fixed.
The tip of the built-in optical fiber F1 is exposed from the tip surface of the ferrule 11, and is mirror-polished together with the ferrule end surface. The rear end of the built-in optical fiber F1 protrudes from the rear end side of the ferrule 11 by a predetermined length and is held by the base member 12 or the like. The rear end surface of the built-in optical fiber F1 is cut, for example, perpendicular to the longitudinal direction or inclined by about 8 °. The rear end surface of the built-in optical fiber F1 may be polished into a convex spherical shape, or may be polished so that the peripheral edge portion is chamfered.

The base member 12 is a substantially semi-cylindrical member made of a resin material such as polyphenylene sulfide (PPS) or polyetherimide (PEI). The base member 12 includes a ferrule holding part 12A for holding the ferrule 11, a bare fiber part (part where the coating is removed) F2a of the connecting optical fiber F2, and a coated fiber part (covering of the connecting optical fiber F2). The portion that has been applied) is divided into a coated fiber holding portion 12C that holds F2b.
A flange portion 121 is formed on the ferrule holding portion 12 </ b> A of the base member 12, and the ferrule 11 is fitted and held on the flange portion 121. The base member 12 and the ferrule 11 may be bonded and fixed.

Fiber fixing grooves 122 are formed along the longitudinal direction on the surfaces of the bare fiber holding portion 12B and the coated fiber holding portion 12C of the base member 12. The built-in optical fiber F1 and the connecting optical fiber F2 are fixed in the fiber fixing groove 122.
As the fiber fixing groove 122, for example, any one of a V-shaped cross section, a U-shaped cross section, and a trapezoidal cross section is suitable, but the built-in optical fiber F1 and the connection optical fiber F2 are connected to the first fiber pressing member 13, The shape is not particularly limited as long as it can be held and fixed between the two-fiber holding member 14.

Specifically, the fiber fixing groove 122 formed in the bare fiber holding portion 12B is a small-diameter groove 122a corresponding to the bare optical fiber outer diameter (for example, 125 μm) of the connection optical fiber F2. The fiber fixing groove 122 formed in the coated fiber holding portion 12C is a large diameter groove 122b corresponding to the coated outer diameter (for example, 250 μm) of the connection optical fiber F2.
On one end side of the large-diameter groove 122b (insertion side of the connection optical fiber F2), a diameter-enlarged portion 122c that is expanded outward is formed so that the connection optical fiber F2 can be easily inserted. Is formed with a coating removal member housing portion 122d for housing the coating removal member 16. The coating removal member 16 removes the coating of the connection optical fiber F2 as the connection optical fiber F2 is inserted along the fiber fixing groove 122. Details of the coating removal member 16 will be described later.

The first fiber pressing member 13 and the second fiber pressing member 14 are lid members made of a resin material such as PPS or PEI. The first fiber pressing member 13 is engaged with a convex piece 123 or the like formed at the center in the longitudinal direction of the base member 12 (near the boundary between the bare fiber holding portion 12B and the coated fiber holding portion 12C). It is mounted on the base member 12 so as to cover 122a. The second fiber pressing member 14 is placed on the base member 12 so as to cover the large diameter groove 122b in a state of being engaged with the convex piece 123 and the like. The space sandwiched between the inner surface of the first fiber pressing member 13 and the inner surface of the second fiber pressing member 14 and the fiber fixing groove 122 of the base member 12 becomes the insertion path of the connecting optical fiber F2.
Further, a notch portion 141 is formed on the inner surface of the second fiber pressing member 14 at a position corresponding to the coating removal member accommodating portion 122d of the base member 12. The sheath removing member 16 is disposed in a space sandwiched between the sheath removing member accommodating portion 122d of the base member 12 and the notch portion 141 of the second fiber pressing member.

  The clamp member 15 is a member having a C-shaped cross section (a U-shape) made of a metal material such as stainless steel, and a part of the side surface is opened. The clamp member 15 presses and holds the first fiber pressing member 13 and the second fiber pressing member 14 on the base member 12. Further, the joint surface between the base member 12 and the first fiber presser member 13 and the joint surface between the base member 12 and the second fiber presser member 14 are exposed to the outside from the opening of the clamp member 15, and the joint surface from the outside is exposed. A wedge (not shown) can be inserted.

  As described above, the optical connector 1 according to the embodiment includes the ferrule 11 to which the built-in optical fiber (first optical fiber) F1 is attached, the connection optical fiber (second optical fiber to be connected) F2, and the built-in optical fiber F1. A base member 12 formed with a fiber fixing groove 122 to be held in abutted state, and a first fiber presser that holds the built-in optical fiber F1 and the connecting optical fiber F2 between the base member 12 and the base member 12 The member 13, the second fiber presser 14, the clamp member 15 that urges the first fiber presser member 13 and the second fiber presser member 14 against the base member 12, and the connecting optical fiber F <b> 2 along the fiber fixing groove 122. The optical fiber connection portion 10 having the coating removal member 16 that removes the coating of the connection optical fiber F2 as it is inserted is a housing. And a loaded configuration grayed.

4 and 5 are perspective views showing the external shape of the coating removal member 16, FIG. 6 is a side view of the coating removal member 16, FIG. 7 is a top view of the coating removal member 16, and FIG. It is.
As shown in FIGS. 4 to 8, the coating removing member 16 is one member in which the coating removing portion 161 and the guide portion 162 are connected by a connecting portion 163, and is made of a synthetic resin material such as PPS or PEI. The When the sheath removing member 16 is attached to the optical fiber connecting portion 10, the guide portion 162 is located at the front stage in the fiber insertion direction, and the sheath removing portion 161 is located at the rear stage in the fiber insertion direction.
By configuring the coating removing member 16 with a synthetic resin material, the manufacturing cost of the coating removing member 16 can be reduced and the weight can be reduced.

The coating removal unit 161 is a part that removes the coating of the connection optical fiber F2 at the end on the fiber insertion side. The coating removal portion 161 has a substantially conical shape, and is formed with a bare fiber insertion hole 161a through which the bare fiber portion F2a of the connection optical fiber F2 can be inserted along the central axis. The bare fiber insertion hole 161a is formed to be larger than the bare optical fiber outer diameter of the connection optical fiber F2 and smaller than the coating outer diameter. Desirably, the outer diameter of the bare fiber insertion hole 161a is set to be 1 to 5 μm larger than the outer diameter of the bare optical fiber of the connection optical fiber F2.
In the present embodiment, the outer diameter of the bare optical fiber is 125 μm, so the outer diameter of the bare fiber insertion hole 161a is about 126 to 130 μm. This is because, when the outer diameter of the bare fiber insertion hole 161a is larger than 130 μm, the clearance between the connection optical fiber F2 and the bare optical fiber is increased, and the removed coating waste is carried into the bare fiber insertion hole 161a.

The fiber insertion side of the bare fiber insertion hole 161a is formed in a tapered shape that decreases in diameter from the fiber insertion port 161b to the inside until reaching a predetermined inner diameter. The taper angle θ ₁ on the fiber insertion side of the bare fiber insertion hole 161a (the angle formed by the central axis AX and the inner surface of the bare fiber insertion hole 161a, see FIG. 9) is preferably set to 15 to 60 °, for example, 30 °. Thereby, the connection optical fiber F2 after the coating removal can be easily inserted into the bare fiber insertion hole 161a. The fiber insertion side of the bare fiber insertion hole 161a may not be formed in a tapered shape.
A hollow portion 161d is connected to the other end side (fiber insertion side) of the bare fiber insertion hole 161a. By forming the bare fiber insertion hole 161a side of the hollow portion 161d into a tapered shape, even if there is a step between the fiber fixing groove 122 of the base member 12 and the bare fiber insertion hole 161a, the tip of the connection optical fiber F2 Can be prevented from being damaged.
The outer surface 161c of the sheath removing portion 161 is formed in a taper shape whose diameter increases from the end on the fiber insertion side toward the other end. That is, the fiber insertion side end of the coating removal portion 161 (the peripheral edge of the fiber insertion port 161b) is formed at an acute angle toward the outside.

The guide part 162 is a part for guiding the connection optical fiber F2 to the coating removing part 161. The guide portion 162 has a substantially cylindrical shape, and is formed with a coated fiber insertion hole 162a through which the coated fiber portion F2b of the connection optical fiber F2 can be inserted along the central axis. That is, the coated fiber insertion hole 162a is formed to be larger than the coated outer diameter of the connection optical fiber F2.
The fiber insertion side of the coated fiber insertion hole 162a is formed in a tapered shape that decreases in diameter from the fiber insertion port 162b toward the inside until reaching a predetermined inner diameter. Thereby, the connection optical fiber F2 can be easily inserted into the coated fiber insertion hole 162a. Note that the fiber insertion port side of the coated fiber insertion hole 162a may not be formed in a tapered shape.

  The coating removal portion 161 and the guide portion 162 are arranged apart from each other by a predetermined length in a state where the central axes of the bare fiber insertion hole 161a and the coating fiber insertion hole 162a coincide with each other, and are integrally formed by connecting portions 163 arranged on both sides thereof. Are joined together.

Here, when the design value of the coating outer diameter of the connection optical fiber F2 is 250 μm, a tolerance of about 5 μm is usually allowed. It is not preferable that the pressing force at the time of removing the coating changes due to the variation in the outer diameter of the coating.
FIG. 14 is a diagram illustrating the relationship between the separation distance between the coating removal portion 161 and the guide portion 162 (the separation distance between the insertion end of the bare fiber insertion hole 161a and the insertion end of the coating fiber insertion hole 162a) and the pressing force during coating removal. It is. FIG. 14 shows a case where the coated fiber outer diameters are 240 μm and 260 μm, and the coated fiber insertion hole 162a has an inner diameter of 265 μm.

In the case of the connection optical fiber F2 having a coating outer diameter of 260 μm, since the clearance with the coating fiber insertion hole 162a is small, the connection optical fiber F2 is guided straight to the coating removal unit 161. Therefore, as shown in FIG. 14, even if the coating removal part 161 and the guide part 162 are separated, the coating of the connection optical fiber F2 can be removed with a small pressing force of about 1N.
However, in the case of the connecting optical fiber F2 having a coating outer diameter of 240 μm, the clearance with the coating fiber insertion hole 162a becomes large. Therefore, if the coating removal portion 161 and the guide portion 162 are too far apart (for example, a separation distance of more than 0.5 mm) It becomes difficult to guide the optical fiber F2 straight to the coating removing unit 161. And as shown in FIG. 14, as a result of the connecting optical fiber F2 being obliquely guided to the coating removing portion 161, the pressing force required for coating removal increases, and in some cases, the connecting optical fiber F2 buckles.

That is, if the separation distance between the coating removal unit 161 and the guide unit 162 is greater than 0.5 mm, the connection optical fiber F2 is not sufficiently aligned, and the end surface of the bare optical fiber of the connection optical fiber F2 is not covered by the coating removal unit 161. It collides with the insertion end and is damaged, or bending occurs, so that a sufficient pressing force is not transmitted to the coating removal unit 161. In other words, if the separation distance between the coating removal portion 161 and the guide portion 162 is 0.5 mm or less, the coating can be removed with a pressing force of about 1 N regardless of the outer diameter of the coating.
On the other hand, when the separation distance between the coating removal unit 161 and the guide unit 162 is smaller than 0.1 mm, the coating waste removed by the coating removal unit 161 does not escape smoothly along the outer surface of the coating removal unit 161, and the coating is removed. The pressing force increases.
Therefore, the separation distance between the coating removal portion 161 and the guide portion 162 is desirably 0.1 mm or more and 0.5 mm or less. In particular, if the separation distance between the coating removal portion 161 and the guide portion 162 is 0.1 mm or more and 0.3 mm or less, the coating of the connection optical fiber F2 can be reliably removed with a small pressing force.

  When the connection optical fiber F2 is to be inserted into the coating removal unit 161 through the guide portion 162, the coating of the connection optical fiber F2 comes into contact with the end of the coating removal unit 161 on the fiber insertion side (periphery of the fiber insertion port 161b). When further pressed in this state, the coating of the connection optical fiber F2 is peeled off and removed. The coating waste removed at the fiber insertion side end of the coating removal portion 161 is accommodated in a space (coating accommodation portion) 164 formed between the coating removal portion 161 and the guide portion 162.

  Thus, the coating removing member 16 can be inserted through the guide portion 162 having the coated fiber insertion hole 162a for guiding the coated connection optical fiber F2 and the bare fiber portion of the connection optical fiber F2 from which the coating has been removed. A coating removal unit 161 that has a bare fiber insertion hole 161a and removes the coating of the connection optical fiber F2 at the end on the fiber insertion side that serves as an insertion port for the connection optical fiber F2, a guide unit 162, and a coating removal unit 161 The separation distance between the insertion end of the coated fiber insertion hole 162a and the insertion end of the bare fiber insertion hole 161a is 0.1 to so that the bare fiber insertion hole 161a and the coated fiber insertion hole 162a are coaxial. A connecting portion 163 that is connected so as to be 0.5 mm is integrally formed.

  In the optical connector 1 in which the coating removal member 16 is installed, when the connection optical fiber F2 is attached to the optical connector 1, a predetermined length of the coating is removed along with the insertion of the connection optical fiber F2. Workability when attaching the connecting optical fiber F2 is remarkably improved. Moreover, since the coating removal part 161 and the guide part 162 are integrally formed on the coating removal member 16, the work of aligning both of them is not necessary, and the assembly work of the optical connector 1 can be facilitated.

Here, the taper angle θ ₂ (angle formed by the central axis AX and the outer surface 161c, see FIG. 9) of the outer surface 161c of the coating removal portion 161 is desirably 60 ° or less, particularly 45 ° or less.
FIG. 10 is a diagram illustrating the relationship between the taper angle θ ₂ of the outer surface 161c of the coating removal unit 161 and the pressing force required for coating removal. As shown in FIG. 10, as the taper angle θ ₂ becomes an acute angle, the pressing force for removing the coating of the connection optical fiber F2 decreases. In particular, when the taper angle θ ₂ is 45 ° or less, the coating of the connection optical fiber F2 can be removed with a small pressing force of about 1N.

Thus, by setting the taper angle θ ₂ of the outer surface 161c of the coating removal portion 161 to 60 ° or less, preferably 45 ° or less, the coating of the connection optical fiber F2 can be removed with a relatively weak pressing force. . Therefore, when the connection optical fiber F2 is attached to the optical connector 1, it is possible to effectively prevent the connection optical fiber F2 from being bent or damaged.
The lower limit of the taper angle θ ₂ is not particularly limited. However, if the angle is too acute, the strength on the fiber insertion side of the coating removal portion 161 may be reduced and easily damaged, and therefore the taper angle θ ₂ is 15 °. The above is desirable.

  The coating removal member 16 is formed by, for example, injection molding using a mold. FIG. 11 is an exploded perspective view showing an example of a mold for producing the coating removal member 16, and FIG. 12 is a top view showing an assembled state of the mold. In FIGS. 11 and 12, the coating removal member mold 20 is divided into four divided parts, that is, a lower mold 21, an upper mold 22, a first side mold 23, and a second side mold 24. The case of configuring is shown.

  The second side mold 24 has a shape in which a core pin 241 protrudes from one end side of a columnar base 240. The core pin 241 has a first outer diameter portion 241a, a second outer diameter portion 241b, and a third outer diameter portion 241c that gradually increase in diameter from the tip toward the base portion 240. The first connecting portion 241d that connects the first outer diameter portion 241a and the second outer diameter portion 241b, and the second connecting portion 241e that connects the second outer diameter portion 241b and the third outer diameter portion 241c are tapered. Is formed.

  The first side mold 23 has a shape in which a convex portion 231 corresponding to the hollow portion 161 d of the coating removal portion 161 is formed on one end side of the cylindrical base portion 230. Further, a pin insertion hole 231a into which the tip of the first outer diameter portion 241a of the core pin 241 is inserted is formed in the convex portion 231 along the central axis.

The lower mold 21 has a shape in which a semicircular first recess 211, a second recess 212, and a third recess 213 are formed in a rectangular parallelepiped base 210.
In the second concave portion 212, a main molding portion 214 for molding the coating removal portion 161 is disposed. In the main molding portion 214, a tapered portion 214a corresponding to the outer surface 161c of the coating removal portion 161 and a pin holding groove 214b for holding the core pin 241 of the second side mold 24 are formed. Further, in the second concave portion 212, portions located on both sides of the main molding portion 214 are L-shaped step portions 215 corresponding to the connecting portions 163.

The first side mold 23 is placed in the first recess 211 in a state where the end face of the base 230 is in contact with the end face of the second recess 212.
The base 240 of the second side mold 24 is placed in the third recess 213. At this time, the third outer diameter from the second outer diameter portion 241b of the core pin 241 is such that the first connecting portion 241d of the core pin 241 protrudes from the pin holding groove 214b of the main molding portion 214 toward the tapered portion 214a. A portion extending over the tip of the portion 241 c is placed in the pin holding groove 214 b of the main molding portion 214. Further, the tip of the first outer diameter portion 241 a of the core pin 241 is inserted into the pin insertion hole 231 a of the first side mold 23.

The upper mold 22 has a face-contrast shape with the lower mold 21. A cavity that defines the overall shape of the coating removal member 16 by surface-bonding the lower mold 21 and the upper mold 22 and inserting the first side mold 23 and the second side mold 24 from the side. Is formed.
The coating removal member 16 is manufactured by press-fitting a resin material into the cavity from a resin injection port (not shown). That is, the bare fiber insertion hole 161 a of the coating removal portion 161 is formed by the first outer diameter portion 241 a of the core pin 241, and the coated fiber insertion hole 162 a of the guide portion 162 is the third outer diameter portion of the core pin 241. 241c.
In addition, the fiber insertion side of the bare fiber insertion hole 161a of the sheath removing portion 161 is formed into a taper shape by the first connecting portion 241d of the core pin 241, and the cavity portion 161d of the sheath removing portion 161 is the first side mold 23. The convex portion 231 is formed.

Thus, in the embodiment, the coating removal member 16 is formed by injection molding using the mold 20. In particular, the core pin 241 of the second side mold 24 is configured so that the bare fiber insertion hole 161a of the coating removal part 161 and the coated fiber insertion hole 162a of the guide part 162 are formed coaxially.
Thereby, the bare fiber insertion hole 161a of the coating removal part 161 and the coated fiber insertion hole 162a of the guide part 162 are formed in a state where the axes are simply and reliably aligned. In addition, the shape (frontage dimension) of the sheath removing portion 161 on the fiber insertion side can be controlled with high accuracy. That is, the coating removal member 16 having high dimensional accuracy can be stably produced.

When the optical connector 1 is assembled, first, the coating removal member 16 is placed on the base member 12 to which the ferrule 11 is fixed, and the first fiber pressing member 13 and the second fiber pressing member 14 are covered. Then, the clamp member 15 is fitted around the base member 12, the first fiber pressing member 13, and the second fiber pressing member 14 to assemble the optical fiber connecting portion 10, and the optical fiber connecting portion 10 is mounted on the housing (not shown) (FIG. 3 ( a)).
Next, a wedge (on the joint surface of the base member 12 and the first fiber pressing member 13 exposed to the outside through the opening of the clamp member 15 and the housing and the joint surface of the base member 12 and the second fiber pressing member 14 ( (Not shown) is pushed in, and the joining surface is slightly separated. In this state, the connecting optical fiber F2 is inserted into the optical fiber connecting portion 10 while keeping the tip of the connecting optical fiber F2 along the fiber fixing groove 122 (large diameter groove 122b) of the base member 12 (FIG. 3B). reference).

The inserted connection optical fiber F <b> 2 is guided to the coating removal unit 161 by the guide unit 162 of the coating removal member 16. When the distal end of the connecting optical fiber F2 comes into contact with the fiber insertion side end of the coating removal portion 161 (the peripheral edge of the fiber insertion port 161b) and is further pressed, the coating is cut by the stress at this time, and the bare optical fiber Is peeled off and removed. Then, only the bare optical fiber passes through the coating removing portion 161 and is inserted into the front (the bare fiber holding portion 12B).
Here, if the tip of the connection optical fiber F2 is pressed in advance with a fingertip, a jig, or the like, the adhesion between the bare optical fiber and the coating is reduced, so that the coating removal member 16 can easily cover the coating with a small pressing load. Can be removed.

  Since the coating removed by the coating removing member 16 is securely accommodated in the coating accommodating portion 164, the coating optical fiber F2 is prevented from being inserted by entering the front together with the bare optical fiber, or the bare optical fiber and the built-in optical fiber F1. It does not become a foreign substance at the connection site with and prevent good optical connection.

When the connecting optical fiber F2 is further pushed in, the connecting optical fiber F2 (bare optical fiber) is abutted against and connected to the built-in optical fiber F1. The coating removal unit 161 removes the coating until the connecting optical fiber F2 hits the built-in optical fiber F1. That is, the portion from the coating removing member 16 to the rear end face of the built-in optical fiber F1 becomes the bare fiber portion F2a.
Then, after the connecting optical fiber F2 is abutted against the built-in optical fiber F1, when the wedge is pulled out, the built-in optical fiber F1 and the connecting optical fiber F2 are connected with each other, the base member 12 and the first fiber pressing member 13, The second fiber pressing member 14 is pressed and held and fixed. In addition, it is desirable to interpose a refractive index matching material between the connection optical fiber F2 and the built-in optical fiber F1. This is to suppress reflection by the air layer between the fiber end faces.

  As described above, in the optical connector 1 according to the embodiment, the connection optical fiber F2 is inserted by the coating removal portion 161 of the coating removal member 16 as the connection optical fiber F2 is inserted along the fiber fixing groove 122 of the base member 12. The coating is removed.

In the optical connector 1, since the coating removal portion 161 and the guide portion 162 are integrally formed so that the bare fiber insertion hole 161a and the coated fiber insertion hole 162a are coaxial, it is necessary to align these axes. There is no. That is, the assembly work of the optical connector 1 is remarkably improved as compared with the case where the covering removal portion 161 and the guide portion 162 are configured as separate members.
Further, when the connection optical fiber F2 is attached to the optical connector 1, the coating of a predetermined length is removed along with the insertion of the connection optical fiber F2, so that the coating of the tip of the connection optical fiber F2 is performed using a dedicated tool. No need to remove. Therefore, workability when attaching the connection optical fiber F2 to the optical connector 1 is significantly improved.
Further, the coating removal length of the connection optical fiber F2 is determined by the distance from the connection site between the built-in optical fiber F1 and the connection optical fiber F2 to the coating removal member 16. Therefore, since the coating is not removed more than necessary from the tip of the connection optical fiber F2, there is no possibility that the strength of the connection optical fiber F2 is reduced and damage is caused.

  As mentioned above, although the invention made by this inventor was concretely demonstrated based on embodiment, this invention is not limited to the said embodiment, It can change in the range which does not deviate from the summary.

  For example, in order to remove the coating of the connection optical fiber F2 at the end of the coating removal unit 161 on the fiber insertion side, at least the peripheral portion of the fiber insertion port 161b may be formed at an acute angle. As described above, the entire coating removal portion 161 may not be formed in a tapered shape. That is, the cross-sectional shape along the central axis AX of the coating removal portion 161 is stepwise in a shape in which the outer surface 161c is linearly expanded as in the embodiment, a hyperbolic shape, or a polygonal line shape. The shape may be increased in diameter.

  Further, the outer surface 161c at the end of the sheath removing portion 161 on the fiber insertion side may have a plane and a curved surface, or planes connected in the circumferential direction, and have a symmetrical shape with respect to the central axis AX. For example, as shown in FIG. 13A, a case where an outer surface 161c is configured by joining a pair of opposing curved surfaces 161e and a pair of opposing flat surfaces 161f at adjacent surfaces is considered. In this case, the coating is easily peeled off in the left-right direction on the paper surface. Further, for example, as shown in FIG. 13B, it is conceivable that two sets of opposing planes 161h and 161i are joined together at adjacent surfaces to form an outer surface 161c.

  By configuring the outer surface 161c of the end portion on the fiber insertion side of the coating removing portion 161 in this manner, the joining end portions 161g and 161j between the flat surface and the curved surface or between the flat surfaces are sharply formed. Accordingly, since the coating of the connection optical fiber F2 is easily torn, the coating of the connection optical fiber F2 can be further easily removed. Further, the direction in which the coating of the connection optical fiber F2 is peeled off can be adjusted by the shape of the coating removal unit 161. In this case, it is convenient to form an opening in the coating removing member 16 along the direction in which the coating of the connection optical fiber F2 is peeled off, so that the coating waste is discharged without remaining in the coating removing member 16. .

In the embodiment, the coating removal member 16 is made of a synthetic resin material such as PPS or PEI. However, the coating removal member 16 may be made of a metal material or a ceramic material that has high hardness and is easy to obtain dimensional accuracy. Also in this case, the coating removal member 16 can be easily produced by injection molding using a mold.
Moreover, the manufacturing method of the coating removal member 16 is not limited to injection molding using a mold, and the coating removal member 16 can be produced by, for example, machining such as cutting or electric discharge.

In the embodiment, the coating removing member 16 is configured as one independent member, but the coating removing member 16 and the ferrule 11 may be formed integrally. Further, the covering removal member 16 may be formed integrally with the base member 12.
This eliminates the need for axial alignment between the built-in optical fiber F1 attached to the ferrule 11 and the bare fiber insertion hole 161a and the coated fiber insertion hole 162a of the coating removal member 16, thereby making it easier to assemble the optical connector 1. It becomes.

  Further, on the inner surface of the coated fiber insertion hole 162a of the coating removing member 16, a cutting blade for forming a cut along the longitudinal direction in the coating of the connection optical fiber F2 may be formed. Thus, after the connection optical fiber F2 is inserted into the guide portion 162, a cut is formed in the coating by the cutting blade while passing through the coated fiber insertion hole 162a. Therefore, the coating of the connection optical fiber F2 can be further easily removed at the coating removing unit 161.

  In the embodiment, the coating removing member 16 is arranged in the coated fiber holding portion 12C of the base member 12, but may be arranged in the bare fiber holding portion 12B. That is, the coating removal member 16 should just be arrange | positioned ahead of the connection site | part of the built-in optical fiber F1 and the connection optical fiber F2.

In the embodiment, the mechanical splice type optical connector 1 (so-called on-site connector) in which the built-in optical fiber F1 is attached to the ferrule 11 in advance and the connection optical fiber F2 is connected to the ferrule 11 in the field has been described. The coating removing member 16 can be provided in the optical connector of the form.
For example, as shown in FIG. 15, the coating removal member 16 may be disposed on the ferrule 11. In the optical connector having the optical fiber connection portion 10 </ b> A shown in FIG. 15, the coating of the optical fiber F is removed by the coating removing member 16 along with the insertion operation of the optical fiber F to be attached. And after making the bare fiber part of the optical fiber F protrude from the front end surface of the ferrule 11, an end surface process will be performed with the ferrule 11. FIG.

As described above, according to the present invention, the member that fixes the positional relationship between the coating removal unit 161 and the guide unit 162 (that is, the bare fiber insertion hole 161a and the coated fiber insertion hole 162a) is provided as a minimum unit. The optical fiber inserted into the coating removal unit 161 is not displaced.
In addition, unlike the structure in which the coating removal unit 161 and the guide unit 162 are configured by a plurality of members, it is not necessary to pay attention to the axial alignment of the coating removal unit 161 and the guide unit 162, so that design and work are facilitated. . Furthermore, if the coating removal portion 161 and the guide portion 162 are configured separately, it is difficult to adjust the distance between the insertion end of the bare fiber insertion hole 161a and the insertion end of the coating fiber insertion hole 162a, but it is integrally formed. This makes it easy to adjust the distance. Moreover, since the coating removal member 16 is incorporated into the optical connector 1 as a minimum unit, a certain degree of accuracy is maintained between the optical connectors.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Optical connector 10 Optical fiber connection part 11 Ferrule 12 Base member 122 Fiber fixing groove 13 First fiber pressing member 14 Second fiber pressing member 15 Clamp member 16 Cover removal member 161 Cover removal part 161a Bare fiber insertion hole 161b Fiber insertion port 161c Outer surface 162 Guide portion 162a Covered fiber insertion hole 162b Fiber insertion port 163 Connection portion 164 Cover receiving portion F1 Built-in optical fiber F2 Connected optical fiber F2a Bare fiber portion F2b Covered fiber portion

Claims (10)

A guide portion having a coated fiber insertion hole for guiding the coated optical fiber;
A coating removal unit that has a bare fiber insertion hole through which the bare fiber portion of the optical fiber from which the coating has been removed can be inserted, and removes the coating of the optical fiber at an end portion on the fiber insertion side that serves as an insertion port for the optical fiber When,
The guide portion and the coating removal portion are arranged such that the bare fiber insertion hole and the coated fiber insertion hole are coaxial, and an insertion end of the coated fiber insertion hole and an insertion end of the bare fiber insertion hole And a plurality of connecting portions that are connected so that the separation distance is 0.1 mm or more and 0.5 mm or less .
The plurality of connecting portions connect the guide portion and the covering removal portion with a part of a side surface so that an open portion is formed between the plurality of connecting portions.
The coating removal member characterized by the above-mentioned.   On the optical fiber insertion side of the bare fiber insertion hole, a cavity is formed,
The coating removal member according to claim 1, wherein The said removal distance is 0.1 mm or more and 0.3 mm or less, The coating | coated removal member of Claim 1 or 2 characterized by the above-mentioned. The said coating removal member is comprised with the synthetic resin material, The coating removal member as described in any one of Claim 1 to 3 characterized by the above-mentioned. The outer surface of the end portion of the fiber insertion side of the coating-removing portion, according to any one of claims 1 to 4, characterized in that it is formed to be inclined at 45 ° or less with respect to the central axis Coating removal member. The outer surface of the end portion on the fiber insertion side of the coating removal portion has a plane and a curved surface, or planes connected in a circumferential direction, and has a symmetrical shape with respect to the central axis. The coating removal member according to any one of 1 to 5 .   A method for manufacturing a coating removal member, comprising molding the coating removal member according to any one of claims 1 to 6 by injection molding using a mold.   The method for manufacturing a coating removal member according to claim 7, wherein the bare fiber insertion hole and the coated fiber insertion hole are formed by the same core pin. A coating removal member according to any one of claims 1 to 6, comprising:
An optical connector characterized in that the coating of the optical fiber is removed by the coating removal unit in accordance with the insertion operation of the optical fiber to be mounted. A ferrule fitted with a first optical fiber;
A base member formed with a fiber fixing groove for holding the second optical fiber to be connected and the first optical fiber in abutment state;
A fiber pressing member that contacts the base member and holds the first optical fiber and the second optical fiber with the base member;
A clamp member that urges the fiber pressing member against the base member, and an optical fiber connecting portion having a structure attached to the housing,
The sheath removing member is disposed in the optical fiber connecting portion;
10. The optical connector according to claim 9, wherein the coating of the second optical fiber is removed by the coating removing unit as the second optical fiber is inserted along the fiber fixing groove.

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