JPH06250028A - Holding structure for optical fiber - Google Patents

Abstract

PURPOSE:To provide the holding structure which is suitable for miniaturization of device, such as optical repeater, and prevents the breakage of an optical fiber and the increase in its transmission loses by inserting the optical fiber into a fiber holding inside body consisting of an elastic material and housing the fiber holding inside body into a fiber holding outside body with a slight margin. CONSTITUTION:The optical fiber 10 is inserted into a hole-shaped or slit-shaped insertion part 30 possessed by the fiber holding inside body 20 consisting of the elastic material. The diameter or the width of the insertion part 30 is slightly larger than the diameter of the optical fiber 10. The fiber holding inside body 20 consists of a first part 20A and second part 20B nearly symmetrical to the plane orthogonal with the central axis of the optical fiber 10. The first part 20A and the second part 20B respectively have tapered surfaces 40A, 40B inclined to the central axis of the optical fiber 10. The fiber holding inside body 20 is housed, with the slight margin, into the fiber holding outside body 60 having tapered inside walls 50A, 50B corresponding to the tapered surfaces 40A, 40B. Then, the axial and diametral movement of the optical fiber 10 is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for holding an optical fiber in a device such as an optical repeater in which the optical fiber is mounted.

In a device such as an optical repeater in which an optical fiber is mounted, an appropriate holding structure is adopted in order to prevent the optical fiber from moving in the longitudinal direction and the radial direction. For example, since the optical submarine repeater applied to the optical submarine cable system is mounted on a cable laying ship, its size is limited, and an optical fiber holding structure suitable for downsizing of the device is required. .

In the present specification, "optical fiber"
The term is used to include those coated with silicone rubber, nylon and the like.

[0004]

2. Description of the Related Art Some conventional holding structures for optical fibers will be described with reference to FIG. In the example shown in FIG. 7 (A),
The optical fiber 102 connected to the optical component 101 fixed to the device frame is covered with the reinforcing cord 103, and the block 104 and the block 104 are fixed to the device frame.
It is sandwiched by a plate 106 which is tightened by a screw 105.

In the example shown in FIG. 7B, the optical component 10
The optical fiber 102 connected to the optical fiber 102 is held by a guide 107 made of resin or the like, or
The block 104 and the screw 105 similar to those in FIG.
And held by the plate 106. In order to avoid damage to the optical fiber 102, two rubber plates 108 are provided between the block 104 and the plate 106, and these two rubber plates 108 are used for the optical fiber 102.
It may be sandwiched between.

[0006]

The optical fiber holding structure of FIG. 7A has the following drawbacks, for example. The fixed portion of the reinforcing cord 103 in the optical component 101 prevents the optical component 101 from being downsized (a portion).

Since the reinforcing cord 103 is thicker than the optical fiber 102, high density mounting is hindered (section b). Since the reinforcing cord 103 is sandwiched between the block 104 and the plate 106, when tension is applied to the optical fiber 102, the force acts on the fixing portion of the optical component 101, and the optical fiber 102 may be broken ( Part c).

The optical fiber holding structure of FIG. 7B has the following drawbacks, for example. When the guide 107 is used, the optical fiber 102 cannot be sufficiently held in the longitudinal direction and the width direction thereof, so that the optical fiber 102 may be broken when tension is applied to the optical fiber 102 (d). Part).

Stress is generated in the optical fiber 102 due to tightening, which causes an increase in optical loss and breakage (part e). Therefore, an object of the present invention is to provide an optical fiber holding structure that is suitable for downsizing of a device such as an optical repeater in which an optical fiber is mounted, and prevents the optical fiber from breaking and increasing optical loss.

[0010]

FIG. 1 is a diagram for explaining the principle of the present invention. First, the optical fiber holding structure of the present invention will be described with reference to FIG. The present invention is not limited to FIG.

The optical fiber 10 has a hole-shaped or slit-shaped insertion portion 30 of the fiber holding inner body 20 made of an elastic body.
Inserted in. The diameter or width of the insertion portion 30 is the optical fiber 1
Slightly larger than 0 diameter.

The fiber holding inner body 20 has a first portion 20 which is substantially symmetrical with respect to a plane orthogonal to the central axis of the optical fiber 10.
A and the second portion 20B. The first portion 20A and the second portion 20B have tapered surfaces 40A and 40B that are inclined with respect to the central axis of the optical fiber 10, respectively.

The fiber holding inner body 20 is accommodated in the fiber holding outer body 60 having tapered inner walls 50A and 50B corresponding to the tapered surfaces 40A and 40B with a slight margin.

[0014]

The optical fiber 10 is inserted into the insertion portion 30 having a diameter or width slightly larger than its diameter, and the fiber holding inner body 20 is accommodated in the fiber holding outer body 60 with a slight margin. 10 radial direction (Fig. 1
(A) (vertical direction) is prevented.

In the present invention, the principle of preventing movement of the optical fiber 10 in the longitudinal direction will be described below. For example, as shown in FIG. 1B, when a force is applied to the optical fiber 10 in the right direction in the figure, the fiber holding inner body 20 moves to the right direction in accordance with this, and the fiber holding inner body 20 moves to the first position. The tapered surface 40B of the second portion 20B abuts on the corresponding tapered inner wall 50B of the fiber holding outer body 60, and the tapered inner wall 50
The fiber holding inner body 20 is elastically deformed by the drag force received from B.

When the fiber holding inner body 20 is elastically deformed,
The diameter or width of the insertion portion 30 is reduced, and the frictional force generated between the insertion portion 30 and the surface of the optical fiber 10 prevents the optical fiber 10 from moving in the longitudinal direction.

As described above, in the present invention, FIG.
This holding structure is suitable for downsizing the device, since the reinforcing cord as shown in FIG. Also, the optical fiber 1
Since 0 does not easily move in the longitudinal direction by an external force, breakage of the optical fiber is prevented. Furthermore, since the optical fiber 10 receives only a slight compressive stress from the fiber holding inner body 20 only when an external force is applied to the optical fiber in the longitudinal direction, there is no possibility of increasing the optical loss.

[0018]

EXAMPLES Examples of the present invention will be described below. FIG. 2 is a diagram showing a first embodiment of the present invention. 2A is a perspective view showing a state in which the optical fiber 11 is inserted into the fiber holding inner body 21, and FIG. 2B is a cross section showing a state in which the optical fiber 11 is housed in the fiber holding outer body 61. It is a figure.

In this embodiment, the fiber holding inner body 21 into which the optical fiber 11 is inserted has a bottom surface which coincides with a first portion 21A having a substantially conical shape and a second portion 21B having a substantially conical shape. It has an integrated shape. Therefore, the tapered surfaces 41A and 41B of the fiber holding inner body 21 form a part of a conical curved surface.

The fiber holding inner body 21 has a hole-shaped insertion portion 3
1 is formed, and the diameter of the insertion portion 31 is 1
Slightly larger than 1 diameter. Fiber holding inner body 21
Is formed of an elastic body such as rubber.

As shown in FIG. 2B, the fiber holding outer body 61 is a tapered surface 41 A of the fiber holding inner body 21.
And 41B, which also have tapered inner walls 51A and 51B that also form a part of a conical curved surface, the fiber holding inner body 21 is slightly different from the fiber holding outer body 61 when the optical fiber 11 is inserted. Be accommodated with a margin. The fiber holding outer body 61 can be obtained, for example, by integrating two or more divided parts made of extruded resin or the like by adhesion or the like.

According to this embodiment, the fiber holding inner body 2
When 1 is elastically deformed in accordance with the principle of FIG. 1, the insertion portion 31 of the fiber holding inner body 21 comes into close contact with the optical fiber 11 almost entirely, so that a relatively large external force acting on the optical fiber 11 causes the optical fiber 11 to move. Movement in the longitudinal direction can be prevented.

FIG. 3 is a diagram showing a second embodiment of the present invention. FIG. 3A shows an optical fiber 11 with a fiber holding inner body 2
2 is a perspective view showing a state of being inserted into FIG. 2, and FIG.
It is sectional drawing which shows the state which accommodated what was shown to (A) in the fiber holding outer body 62.

The fiber-holding inner body 22 has a first symmetrical structure.
It is composed of a portion 22A and a second portion 22B. A parallel slit-shaped insertion portion 32 into which the optical fiber 11 is inserted is formed in the fiber holding inner body 22, and the width of the insertion portion 32 is slightly larger than the diameter of the optical fiber 11.

The first portion 22A of the fiber holding inner body 22 has two flat tapered surfaces 42A, which in this embodiment are part of two opposite pyramids of a quadrangular pyramid. . Similarly, the second portion 22B of the fiber holding inner body 22 also has two flat tapered surfaces 42B.

The fiber holding outer body 62 has tapered inner walls 52A and 52B corresponding to the tapered surfaces 42A and 42B of the fiber holding inner body 22, respectively, and the fiber holding inner body 22 has the optical fiber 11 inserted therein. It is accommodated in the fiber holding outer body 62 with a slight margin. In this example, the tapered surfaces 42A and 4A of the fiber holding inner body 22 are
2B are tapered surfaces 52A of the fiber holding outer body 62, respectively.
And 52B.

According to this embodiment, the fiber holding inner body 2
No curved surface processing is required for the fiber-holding outer body 62 and the fiber-holding outer body 62, so that the parts can be easily manufactured. Further, since the slit-shaped insertion portion 32 is formed in the fiber-holding inner body 22, the optical fiber 11 is inserted. The work of inserting into the portion 32 is easy.

In this embodiment, the first portion 22A and the second portion 22B of the fiber holding inner body 22 each have two tapered surfaces, but four tapered surfaces may be formed in each portion. . Further, the shape of the fiber holding inner body may be set so that each tapered surface forms a part of a polygonal pyramid slant surface other than the quadrangular pyramid.

FIG. 4 is a diagram showing a third embodiment of the present invention. FIG. 4 (A) is a perspective view showing a state in which an optical fiber is inserted into a fiber holding inner body, and FIGS. 4 (B) and 4 (C) are cross-sections of the cross section orthogonal to each other as shown in FIG. 4 (A). It is a figure.

In this embodiment, four optical fibers 12, 13, 14 and 15 are inserted into a fiber holding inner body 23 having an outer shape similar to that of the fiber holding inner body 22 in the second embodiment of FIG. . The optical fibers 12, 13, 14 and 15 are parallel to each other, and the insertion portion of the fiber holding inner body 23 has a hole shape.

As shown in FIGS. 4B and 4C, the fiber holding outer body 63 has a tapered inner wall corresponding to the taper surface of the fiber holding inner body 23, and the fiber holding inner body 23 has a tapered inner wall. Are accommodated in the fiber holding body 63 with a slight margin.

According to this embodiment, when a plurality of optical fibers are to be held at the same time, a significant space saving can be achieved as compared with the prior art. The reason why the optical fibers are held in parallel is to prevent undesired deformation of the fiber holding inner body 23 when an independent external force is applied in the longitudinal direction of each optical fiber.

FIG. 5 is a sectional view of an optical fiber holding structure showing a fourth embodiment of the present invention. In this example, the fiber holding inner body 24 has a first portion 24A having a tapered surface 44A forming a part of a conical curved surface and a second portion 24 having the same shape.
B and. 44B is a tapered surface of the second portion 24B.

The first portion 24A and the second portion 24B are integrally formed or integrally formed so that the diameter of the central portion is smaller than the diameter of both end portions. The insertion portion 34 of the fiber holding inner body 24 has a hole shape.

The fiber holding outer body 64 has tapered inner walls 54A and 54B having shapes corresponding to the tapered surfaces 44A and 44B of the fiber holding inner body 24, respectively.
The fiber holding inner body 24 is accommodated in the fiber holding outer body 64 with a slight margin while the optical fiber 11 is inserted.

Also in this embodiment, the movement of the optical fiber 11 in the longitudinal direction is prevented according to the principle of FIG. Although the tapered surfaces 44A and 44B of the fiber holding inner body 24 form a part of a conical curved surface, a fiber holding inner body having no curved surface may be formed according to the second embodiment of FIG.

FIG. 6 is a diagram showing another embodiment applicable to all the above-described embodiments. FIG. 6A is the first of FIG.
This corresponds to a modification of the embodiment, and a fiber holding outer body that accommodates the fiber holding inner body 21 in a state where the optical fiber 11 is inserted is formed from two parts 61A and 61B divided in the longitudinal direction of the optical fiber 11. is doing.

The example shown in FIG. 6B also corresponds to a modification of the first embodiment shown in FIG. 2. In this example, the fiber holding inner body 21 is accommodated with the optical fiber 11 inserted. The fiber holding outer body is divided into two parts on both sides of the optical fiber 11 (61
C, 61D).

FIG. 6C corresponds to a modification of the second embodiment of FIG. 3, and in this example, the fiber holding outer body does not surround the entire circumference of the fiber holding inner body but has a plate shape. The fiber holding inner body accommodating portion 65A is formed in an open form on one surface of the fiber holding outer body 65. Also in these examples, the movement of the optical fiber in the longitudinal direction can be prevented according to the principle of FIG.

[0040]

As described above, according to the present invention,
There is an effect that it is suitable for miniaturization of a device such as an optical repeater in which an optical fiber is mounted, and it becomes possible to provide an optical fiber holding structure that prevents breakage of the optical fiber and increase in optical loss.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a perspective view and a sectional view showing a first embodiment of the present invention.

FIG. 3 is a perspective view and a sectional view showing a second embodiment of the present invention.

FIG. 4 is a perspective view and a sectional view showing a third embodiment of the present invention.

FIG. 5 is a sectional view showing a fourth embodiment of the present invention.

FIG. 6 is a sectional view and a perspective view showing another embodiment applicable to the first to fourth embodiments of the present invention.

FIG. 7 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 10 Optical Fiber 20 Fiber Holding Inner Body 30 Insertion Part 40A, 40B Tapered Surface 50A, 50B Tapered Inner Wall 60 Fiber Holding Outer Body

Claims (4)

[Claims] 1. An optical fiber (10) has a hole-shaped or slit-shaped insertion portion (3) of a fiber holding inner body (20) made of an elastic body.
0), the diameter or width of the insertion portion (30) is slightly larger than the diameter of the optical fiber (10), the fiber holding inner body (20) is the central axis of the optical fiber (10). It is composed of a first part (20A) and a second part (20B) which are substantially symmetrical with respect to an orthogonal plane, and the first and second parts (20A, 20B) are respectively with respect to the central axis of the optical fiber (10). The fiber holding outer body (60) having a taper surface (40A, 40B) inclined and the fiber holding inner body (20) has a taper inner wall (50A, 50B) corresponding to the taper surface (40A, 40B). An optical fiber holding structure characterized in that it is accommodated with a slight margin. 2. The optical fiber holding structure according to claim 1, wherein the tapered surface forms a part of a conical curved surface. 3. The optical fiber holding structure according to claim 1, wherein the tapered surfaces of the first and second portions are at least two flat surfaces each forming a part of a polygonal pyramid slant surface. . 4. The optical fiber holding structure according to claim 1, wherein there are a plurality of the insertion portions, the same number of the optical fibers as the insertion portions, and the plurality of the optical fibers are parallel to each other.