JPH08160269A - Optical cable terminal structure - Google Patents

Abstract

PURPOSE: To provide an optical cable terminal structure which is a flexible protection cylinder body and widens the storage space of the protection cylinder body and also never damages an optical connector in the protection cylinder body. CONSTITUTION: A jacket 2 at the terminal of an optical cable 1 having a tension member 3 is peeled to draw the coated optical fiber 4 of a specific length out of the terminal part, and the optical connector 5 is fitted to the end part of the drawn-out coated optical fiber 4 and stored in a storage body 14, and the coated optical fiber 4 fitted to the optical connector 5 stored in the storage part 13 is stored in the flexible protection cylinder body 6 which is equipped with a traction end 6B at one end and fixed to the jacket 2 at the end part of the optical fiber 1 at the other end and has tensile force resistance, and the tension member 3 is connected to the flexible protection cylinder body 6 through a flange 11 fixed to the end part of the optical cable 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical cable terminal structure with an optical connector, and more particularly to an optical cable terminal structure having a protective cylinder provided with a pulling member at an end of an optical cable.

[0002]

2. Description of the Related Art An optical cable with an optical connector in which an optical connector is attached to an end of an optical fiber core which is pulled out from an end of the optical cable by a predetermined length, and the optical fiber core is usually housed in a protective cylindrical body. Fixed on the terminal. By providing a pulling member at the tip of the protective cylinder, a pulling rope is connected to the pulling member when the optical cable is laid, and the pulling member is pulled through the inside of the duct, the pipe or the like.
An optical cable terminal structure with an optical connector is, for example, as shown in FIG. 2 or FIG.

In an optical cable terminal structure 20 shown in FIG. 2, a flange 21 is fixed to an outer jacket 2 of an end of an optical cable 1, and a tension member 3 is fixed to a terminal of a tension member 3 exposed from the optical cable terminal at a tip of the flange 21. While fixing the base end portion of the pulling portion 22, the end of the tension member 24 connected to the pulling member 23 is fixed to the tension member pulling portion 22 and connected to the tension member 3 of the optical cable 1 to pull the end of the optical cable 1. A protective cylinder 26 formed of a synthetic resin member such as plastic is capped between the member 23 and the end of the optical cable 1 is exposed in the protective cylinder 26 and on the front side of the tension member retracting portion 22. The extra length portion 4a of each optical fiber core wire 4 and each optical connector 5 respectively connected to the end portions of these optical fiber core wires 4 are accommodated. It is obtained by way.

An optical cable terminal structure 30 shown in FIG. 3 is made of metal in which a tension member retracting portion 31 is fixed to the end of the tension member 3 exposed from the end of the optical cable 1 and a pulling member 32 such as an eyebolt is fixed to the tip. Of the optical cable 1, and the optical connector 5 connected to the end of the optical fiber core wire 4 exposed from the terminal of the optical cable 1 is housed in the protective tube 33. The tension member retracting portion 31 is fixed from the outside of the protective cylindrical body 33 by a screw 34 in the vicinity of the base end portion.

[0005]

In the optical cable terminal structure 20 shown in FIG. 2, the tension applied to the pulling member 23 when pulling the optical cable 1 is the tension member 2.
4. Tension member retracting portion 22 Further, the tension member 3 is added to the tension member 3 of the optical cable 1, and the tension member retracting portion 22 is not applied to the optical fiber core wire 4 or the like in the protective cylinder 26 at all. The optical cable terminal structure 20 is flexible because the protective tubular body 26 is made of plastic, so that it can be pulled in a bent conduit. Further, since the optical connector 5 is attached and fixed to the optical connector attaching plate 25 or the like fixed to the tension member 24, the optical connector 5 is protected by the protective tubular body 2 during pulling.
There is no violence in 6 and the optical connector 5 is not damaged.

However, this optical cable terminal structure 20 is
The tension member 24 penetrates through the center of the protective cylinder 26,
Further, a protective plate 27 for preventing the protective cylinder 26 made of plastic from being crushed by lateral pressure on the tension member 24.
Since ~ 29 are provided at a plurality of locations, there is a problem that the storage space for the optical fiber core wire 4 and the optical connector 5 is limited, and it is difficult to reduce the diameter of the optical cable with an optical connector.

In the optical cable terminal structure 30 shown in FIG. 3, the tension applied to the pulling member 32 when the optical cable 1 is pulled is the protective cylinder 33 and the tension member retracting portion 3.
1 Further, the structure is such that it is added to the tension member 3 of the optical cable 1 and is not added to the optical fiber core wire 4 or the like in the protective cylinder 33 at all. Since this optical cable terminal structure 30 receives the tension by the protective cylindrical body 33, there is an advantage that a tension member is not required in the protective cylindrical body 33 and the space for housing the spectral fiber core wire 4 and the optical connector 5 is increased.

However, since the protective cylinder 33 is made of metal and is not flexible, there is a problem that it is difficult to pull it inside the bent conduit. Although it is possible to give flexibility by forming the protection cylinder 33 as a corrugated tube, the protection cylinder 33
Since the optical connector 5 therein is not supported by anything inside the protective cylinder 33, the optical connector 5 is protected by the protective cylinder 33 during pulling.
In some cases, the optical connectors 5 collide with each other and collide with each other to damage the optical connectors 5. Further, since the optical fiber core wire and the optical connector 5 are directly inserted into the protective cylindrical body 33, it is difficult to pass the optical connector 5 because the optical connector 5 is caught by the unevenness of the swamp particularly in the case of a corrugated tube. In an extreme case, the optical connector 5 may be caught and the optical fiber core may buckle and break. Further, when the corrugated tube is bent, the optical connector 5 may be sandwiched between the waves and the optical connector 5 may be damaged. Further, when the protective cylinder 33 is disassembled after the pulling is completed, the optical connector 5 is exposed, so that dust may be attached to or damaged on the optical connector 5.

The present invention solves the above-mentioned problems and is a flexible protection cylinder, which widens the storage space in the protection cylinder and does not damage the optical connector in the protection cylinder. An object is to provide an optical cable terminal structure.

[0010]

The present invention has the following means in order to solve the above problems.

In the optical cable terminal structure according to claim 1 of the present invention, the jacket of the terminal of the optical cable having the tension member is peeled off, and an optical fiber core wire of a predetermined length is pulled out from the end portion of the optical fiber core wire end. An optical fiber is attached to the optical connector, the optical connector is accommodated in a container, and the optical fiber core to which the optical connector accommodated in the container is attached has a pulling member at one end and the other end of the optical cable. The flexible member is housed inside a flexible protective cylinder having a tensile strength that is fixed to the jacket, and the tension member is provided through a flange fixed to the end of the optical cable. Characterized by being connected to the body.

The optical cable terminal structure according to claim 2 of the present invention is characterized in that the flexible protective cylinder is a tube with a metal wave.

The optical cable terminal structure according to a third aspect of the present invention is characterized in that the flexible protective cylinder is made of plastic in which a metal tensile strength wire is folded in a spiral shape or a stitch shape.

[0014]

According to the optical cable terminal structure of the first aspect of the present invention, the outer jacket of the end of the optical cable having the tension member is peeled off, and the optical fiber core wire of a predetermined length is drawn out from the end portion. The optical connector is attached to the end of the optical connector, the optical connector is stored in the storage body, and the optical fiber core wire with the optical connector stored in the storage body is stored inside the protective cylinder body. Since there are no tension members inside the tube, the storage space inside the protective tube is sufficient, and even if the optical connector moves during the pulling of the optical cable, the optical connector is stored in the housing, so that it may run wild. Without the optical connector is not damaged.

Further, since the protective tubular body has a pulling member at one end and the other end is a flexible protective tubular body having a tensile strength that is fixed to the outer cover of the end portion of the optical cable, the pulling of the optical cable is prevented. The tension is applied to the traction member, the flexible protective cylinder having anti-tension resistance, and the tension member of the optical cable connected to the flexible protective cylinder via the flange fixed to the end of the optical cable. No tension is applied to the optical fiber core or the like inside the flexible protective cylinder by pulling.

According to the optical cable terminal structure of the second aspect of the present invention, since the flexible protective cylinder is a metal corrugated tube, it has sufficient strength against lateral pressure. Further, the flexible protective cylinder is a corrugated tube, but the optical connector in the protective cylinder is housed in the housing, so that even when the corrugated tube is bent, it is not caught between the waves. . Further, although the protective tube is a corrugated tube, the optical connector is housed in the housing, so that the optical connector can be easily passed through the protective tube without causing any trouble. Furthermore, during standby before installation of the optical cable, dew condensation may occur in the protective cylinder due to temperature fluctuations. In particular, if the protective cylinder is made of metal, its effect is great, but since the optical connector is housed in the housing, even if dew condensation occurs in the protective cylinder, it does not affect the optical connector.

According to the optical cable terminal structure of the third aspect of the present invention, since the flexible protective tubular body is made of plastic in which the tensile strength wire made of metal is folded in a spiral shape or a stitch shape, a metal corrugated tube It has sufficient flexibility compared to Further, although the strength against lateral pressure is slightly inferior to that of the metal corrugated tube, the protective cylinder does not collapse due to lateral pressure.

[0018]

The present invention will be described below in detail with reference to examples. The same parts as those of the conventional one are designated by the same reference numerals and detailed description thereof will be omitted.

The optical cable terminal structure of the present invention will be described with reference to FIG. The optical cable terminal structure 10 of the present invention is one in which a flexible protective cylinder 6 is provided at the end of the optical cable 1. The flexible protective cylinder 6 is made of, for example, a corrugated tube made of stainless steel, or a tensile strength wire such as a stainless steel wire or a high tensile resin fiber is vertically attached to or braided around the corrugated tube. It is covered with an object and is fixed to a pulling flange 6B and a flange 11 which will be described later by welding, or an adhesive material, and a pulling flange 6B having an eyebolt 6A is hermetically welded or brazed to the tip thereof. It is stuck in. The rear end of the protective tubular body 6 is hermetically and detachably fixed to a flange 11 fixed to the end portion of the jacket 2 of the optical cable 1. 6C1 is packing,
Reference numeral 6C2 is a fixing bolt. A tension member retracting portion 12 for fixing the tension member 3 of the optical cable 1 is detachably attached to the end surface of the flange 11 inside the protective tubular body 6 by a bolt or the like.

The tension member 3 and the sleeve 12A of the tension member retracting portion 12 are integrally fixed by caulking. The outer cover 2 and the flange 11 of the optical cable 1 are wrapped with a waterproof seal 11A to keep airtightness. A part of the optical fiber core wire 4 and an optical connector 5 housed in a transparent or semitransparent plastic bag-shaped housing 13 such as polyethylene are housed inside the protective cylinder 6. The housing 13 may be a plastic sheet that can be bent or rolled to accommodate the optical connector 5.

The optical cable terminal structure 10 as described above is formed by the following procedure. The outer jacket 2 of the end of the optical cable 1 having the tension member 3 is peeled off for a predetermined length, and the optical fiber core wire 4 is pulled out from the end portion with an extra length 4a of a predetermined length. An optical connector 5 is attached to the. A plurality of optical fiber core wires 4 to which the optical connector 5 is attached are collectively housed in a plastic bag-shaped container 13 and the inlet side of the bag-shaped container 13 is sealed by an appropriate means.

Next, a disc-shaped metal flange 11 having a through hole into which the optical cable 1 is inserted is inserted in the end portion of the jacket 2 of the optical cable 1 and hermetically fixed by a known means. Prior to fixing the flange 11 to the jacket 2 of the optical cable 1, a predetermined length is pulled out from the end portion of the optical cable 1 to a sleeve 12A of a tension member retracting portion 12 provided on the end surface of the flange 11 on the tip side of the optical cable 1. Inserting the tension member 3
Then, the tension member 3 is caulked and fixed.

Thereafter, a part of the optical fiber core wire 4 and the optical connector 5 accommodated in the accommodating body 13 are accommodated in the protective cylinder body 6 and the base end portion of the protective cylinder body 6 is hermetically attached to the flange 11. Then, the optical cable terminal structure 10 is formed by integrally fixing with the fixing bolt 6C2.

In the optical cable terminal structure constructed as described above, the tension when pulling the optical cable is applied to the tension member 3 via the pulling flange 6B, the flexible protective cylinder 6, the flange 11 and the tension member retracting portion 12. It will be. Therefore, tension due to pulling is not applied to the optical fiber core wire 4 and the like in the protective cylinder 6.

[0025]

As described above, according to the optical cable terminal structure of the present invention, the outer jacket of the end of the optical cable having the tension member is peeled off, and the optical fiber core wire of a predetermined length is pulled out from the end portion, so that the optical fiber An optical connector is attached to the end of the fiber core wire, and the optical connector is housed in a housing,
The optical fiber core with the optical connector installed in the housing is housed inside the protective cylinder, so there is no tension member inside the protective cylinder, so the storage space inside the protective cylinder is sufficient. Moreover, even if the optical connector moves during the pulling of the optical cable, it is stored in the storage body, so it does not run wild and a part of the optical fiber core and the optical connector stored are not damaged. .

Further, since the protective tubular body has a pulling member at one end and the other end is a flexible protective tubular body having a tensile strength that is fixed to the outer jacket of the end portion of the optical cable, the pulling of the optical cable is prevented. The tension at this time can be applied to the traction member, the flexible protective cylinder having anti-tension resistance, and the tension member of the optical cable connected to the flexible protective cylinder through the flange fixed to the end of the optical cable. Tension due to pulling is not applied to the optical fiber core wire or the like in the flexible protective cylinder.

According to the optical cable terminal structure of the second aspect of the present invention, since the flexible protective tubular body is the metal corrugated tube, it has sufficient strength against lateral pressure. Further, the flexible protective cylinder is a corrugated tube, but the optical connector in the protective cylinder is housed in the housing body. Therefore, even when the corrugated tube is bent, the optical connector 5 is sandwiched between the waves. There is no end.
Further, although the protective tube is a corrugated tube, the optical connector is housed in the housing, so that the optical connector can be easily passed through the protective tube without causing any trouble. Furthermore, during standby before installation of the optical cable, dew condensation may occur in the protective cylinder due to temperature fluctuations. In particular, if the protective cylinder is made of metal, its effect is great, but since the optical connector is housed in the housing, even if dew condensation occurs in the protective cylinder, it does not affect the optical connector.

According to the optical cable terminal structure of the third aspect of the present invention, since the flexible protective tubular body is made of plastic in which metal tensile strength wires are folded in a spiral shape or a stitch shape, a metal corrugated tube It has sufficient flexibility compared to Further, although the strength against lateral pressure is slightly inferior to that of the metal corrugated tube, the protective cylinder does not collapse due to lateral pressure.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an optical cable terminal structure of the present invention.

FIG. 2 is a sectional view showing an example of a conventional optical cable terminal structure.

FIG. 3 is a sectional view showing another example of a conventional optical cable terminal structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical cable 2 Outer sheath 3 Tension member 4 Optical fiber core wire 5 Optical connector 6 Protective cylinder body 6B Traction flange 11 Flange 12 Tension member retaining portion 13 Storage body

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinji Nagasawa 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Inside Nippon Telegraph and Telephone Corporation (72) Inventor Mikio Tsutsumi 1-1-1 Uchisaiwaicho, Chiyoda-ku, Tokyo No. 6 Nippon Telegraph and Telephone Corporation

Claims (3)

[Claims] 1. An optical cable having a tension member, a jacket of an end of the optical cable is peeled off, an optical fiber core wire of a predetermined length is pulled out from an end portion, and an optical connector is attached to the end portion of the optical fiber core wire. An optical fiber core wire, which is housed in a housing body and to which the optical connector housed in the housing body is attached, has a pulling member at one end and has a tensile strength that is fixed at the other end to the jacket of the end portion of the optical cable. The tension member is housed inside a flexible protective cylinder, and the tension member is connected to the flexible protective cylinder via a flange fixed to an end of the optical cable. Optical cable terminal structure. 2. The optical cable terminal structure according to claim 1, wherein the flexible protective cylinder is a metal corrugated tube. 3. The optical cable terminal structure according to claim 1, wherein the flexible protective cylinder is made of plastic in which a metal tensile strength wire is folded in a spiral shape or a stitch shape.