JP2007140001A - Straight line joint structure of optical drop cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a straight line joint structure of an optical drop cable by a simple optical connector connection system. <P>SOLUTION: Each optical cable 15 and a support line 16 are separated in the neighborhood of the edge of the optical drop cable 11 of both sides to be connected. An optical connector 25 is attached and mutually optically connected to each optical cable 15 respectively. The support lines 16 are connected by caulking of connection sleeve 28 for instance. The optical cable 15 is grasped by a cable grasp part 32 of both ends of a slender base member 31. The optical connector 25 is fixed with a tape winder 33 or the like on a base member 31. For instance, a protection sleeve 22 passing through one optical drop cable 11 is previously drawn to be covered on a part such as the optical connector 25 and a base member 31. An end face cap is attached to both the ends of the protection sleeve 22 to close the opening the protection sleeve 22. A straight line joint is easily compact and lightweight. Assembly is easy. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical drop cable for drawing an optical fiber from an aerial optical cable of an optical communication network into each house, and more particularly to a linear connection structure of an optical drop cable in which an optical cable portion and a support line are integrated.

When drawing an optical fiber from an aerial optical cable of an optical communication network to each house, it is necessary to connect the optical drop cable drawn from the aerial optical cable to the optical drop cable on the house side. In this case, a termination box is attached to the outer wall of the house. Is generally used, and a connection portion between optical drop cables is accommodated in the termination box.
Further, when a straight connection structure using a small optical closure is used, a connection structure using a mechanical splice 4 as shown in FIG. 8 is also common. In the figure, reference numeral 1 denotes an optical drop cable. As shown in FIG. 8A, the optical drop cable 1 has a structure in which the optical cable portion 2 and the support wire 3 are integrated. The ends of the optical drop cables 1 on both sides are torn into an optical cable portion 2 and a support wire 3 portion, and the optical fiber cores 2a exposed from the optical cable portion 2 are connected by a mechanical splice (optical fiber connector) 4. The ends of the support wires 3 on both sides are connected and fixed by caulking with a lap crimping tool through the connecting sleeve 6 after peeling off the resin coating. Then, as shown in FIG. 8 (b), the protective sleeve 7 previously passed through the optical drop cable 1 is slid to cover the entire vicinity of the connecting portion, and the end cap 8 also passed through the optical drop cable 1 in advance. Is put on both ends of the protective sleeve 7. Although not shown, taping is applied to the boundary between the protective sleeve 7 and the end cap 8 and the boundary between the end cap 8 and the optical drop cable 1.

The connection method using the conventional optical termination box is not used when the user does not want to make a hole in the wall because a hole is made in the wall of the house in order to attach the optical termination box.
On the other hand, the method using a mechanical splice is preferable in that it does not require a hole in the house wall, but the connection by the mechanical splice is basically a permanent connection and is not easy to maintain. A small closure system using a connector is desired.

  The present invention has been made to solve the above-mentioned conventional drawbacks, and provides a linear connection structure of an optical drop cable using a detachable optical connector in a closure system that does not require a hole in a house wall. With the goal.

The invention structure of claim 1 that solves the above problem is a straight connection structure of an optical drop cable in which an optical cable part and a support line are integrated,
A pair of optical connectors attached to the ends of the optical cables on both sides to be connected are connected to each other, the optical connectors in the connected state are fixed to an elongated base member, and cable gripping portions provided on both sides of the base member Grip the optical cables on both sides with the support wires, and fix the support wires on both sides with the support wire fixing means. Cover the optical connector, cable gripping portion and support wire fixing portion with a cylindrical protective sleeve. Both ends of the sleeve are each covered with an end cap for closing the opening of the protective sleeve.

  A second aspect of the present invention is characterized in that, in the first aspect, optical connector portions on both sides connected to each other and support line portions on both sides fixed to each other are provided along the elongated base member. To do.

  A third aspect of the present invention is characterized in that, in the first aspect, the protective sleeve is composed of a pair of halved members, and has a cylindrical shape as a whole when the halved members are combined.

  A fourth aspect of the present invention is the structure according to the first or second aspect, wherein the end face cap is composed of a pair of halved pieces connected by a thin hinge portion, and the edges of the halves engage when the halved pieces are closed. It is characterized by that.

  In a fifth aspect of the present invention, in the first to fourth aspects, a circumferential groove member having a cylindrical shape through which the optical drop cable is inserted and having a circumferential groove on the outer surface is disposed at both end positions of the base member, and A protrusion that fits in the circumferential groove of the groove member is formed.

  According to a sixth aspect of the present invention, the circumferential groove member according to the fifth aspect is integral with the base member.

  A seventh aspect of the present invention is characterized in that, in the first to sixth aspects, a circumferential groove is formed in the vicinity of both ends of the protective sleeve, and a protrusion that fits into the circumferential groove on the outer periphery of the protective sleeve is formed on the inner surface of the terminal cap. And

According to the straight connection part structure of the optical drop cable of the present invention, unlike the termination box, it can be hung and installed in front of the house without being attached to the wall. Therefore, the optical cable can be drawn into the house without making a hole in the wall.
Moreover, the assembly of the straight connection structure of the present invention is easy compared to the conventional straight connection structure using a mechanical splice.
Moreover, the linear connection part structure of this invention is small and lightweight, and is suitable for installing in the middle of an optical drop cable.

  Hereinafter, a straight connection structure of an optical drop cable embodying the present invention will be described with reference to the drawings.

  An example of the optical drop cable targeted in this embodiment is shown in FIG. This optical drop cable 11 includes a portion of an optical cable 15 in which a tensile strength material 13 is disposed on both sides of a single optical fiber core wire 12 and a resin coating (sheath) 14a such as polyethylene or polyvinyl chloride is applied, and a steel wire 16a. In this configuration, the portion of the support wire 16 provided with the resin coating 14b is integrally connected via a constricted portion 14c. Further, a notch 14d is provided in the resin coating 14a of the optical cable 15 portion, and the optical fiber core wire 12 can be easily taken out by tearing from the notch 14d.

1 to 6 show a procedure for obtaining a straight connection structure 21 of an optical drop cable according to an embodiment of the present invention.
First, as shown in FIG. 1A, the optical cable 15 and the support line 16 are separated from each other by tearing the constricted portion 14c from the tip of the optical drop cable 11 on both sides to an appropriate length. Then, a cylindrical protective sleeve 22 is inserted in advance into one of the optical drop cables 11. Further, as shown in FIG. 1B, a cylindrical circumferential groove member 23 made of rubber or the like in which a circumferential groove 23a for engaging an end face cap is formed is inserted into the optical drop cables 11 on both sides.

Next, as shown in FIG. 2, a sheath SC connector 25, which is a field-attached connector in this embodiment, is attached to the optical cables 15 on both sides, and both the sheath grip SC connectors 25 are fitted into adapters 26, respectively. Butt and make an optical connection.
The jacket gripping SC connector 25 is integrally provided with a jacket gripping portion 27 so that the jacket portion of the optical cable 15 can be gripped. Although a detailed structure of the outer cover gripping portion 27 is omitted, a general structure can be adopted. For example, the outer cover portion is composed of a base and a lid portion that are connected to each other by a hinge portion at a side edge so as to be opened and closed A structure that grips and locks can be employed.
Further, the support wires 16 on both sides are squeezed through the connecting sleeve (support wire fixing means) 28, and the support wires 16 are fixedly connected to each other.

FIG. 3A shows a stage following FIG. 31 is a base member. As shown in FIG. 3 (b), the base member 31 has a cable gripping portion 32 formed with slits 32a at both ends, the optical cable 15 is fitted into the slit 32a, and the optical cable 15 is gripped by the jacket portion. .
Next, the jacket gripping SC connectors 25 on both sides are fixed to the base member 31 by fixing means such as tape winding. Reference numeral 33 denotes a tape winding portion which is a fixing means. Note that a fixing method in which the tape including the adapter 26 is also used may be used. Also, other fixing methods can be employed.

  Next, as shown in FIG. 4 (a), the cylindrical protective sleeve 22 previously passed through the one optical drop cable 11 covers the outer gripping SC connector 25, the adapter 26, the base member 31, and the like. So draw and cover them. As shown in FIG. 4B, the protective sleeve 22 has a peripheral groove 22a for engaging an end face cap in the vicinity of both ends thereof.

Next, as shown in FIG. 5, end caps 34 are attached to both ends of the protective sleeve 22. The end cap 34 is composed of a pair of halved pieces 36 and 37 connected by a thin hinge portion 35, and the inner circumferential surface of each of the halved pieces 36 and 37 is fitted in the circumferential groove 23 a of the circumferential groove member 23. The protrusions 36 a and 37 a and the protrusions 36 b and 37 b in the circumferential direction that fit into the peripheral groove 22 a on the outer periphery of the protective sleeve 22 are formed. Further, the engaging claw 37c is provided in the side edge portion of the other half piece 37, and the engaging hole (not shown) is provided in the side edge portion of the one half piece 36, and both the half pieces 36 and 37 are closed. The engaging claws 37c are engaged with the engaging holes so as to engage with each other.
FIG. 5 shows that one half piece 36 of each end cap 34 is fitted so that the protrusion 36a is fitted in the circumferential groove 23a of the circumferential groove member 23 and the protrusion 36b is fitted in the circumferential groove 22a on the protective sleeve 22 side. The other half piece 37 is then rotated around the thin hinge portion 35 so as to cover the one half piece 36, and the engaging claw 37c. When the two half-split pieces 36 and 37 are closed by engaging the engagement holes with the engagement holes, the protective sleeve 22 is coupled to the circumferential groove members 23 on both sides thereof via the end caps 34.
In this case, since the circumferential groove members 23 on both sides hit both ends of the base member 31 holding the optical cable 15 and the movement in the cable length direction is restricted, the protective sleeve 22 and the circumferential groove member 23 are in the cable length direction. Never move.
Further, the structure in which the protrusions 36 a and 37 a on the end face cap 34 side are fitted in the peripheral groove 23 a of the peripheral groove member 23 serves to make the opening of the end face cap 34 watertight. Furthermore, other water-tightening means can be employed.

  In this embodiment, the circumferential groove member 23 is a separate member from the base member 31, but the circumferential groove member 23 may be formed integrally with the base member 31. In that case, the base member with a circumferential groove member is set in the stage of FIG.

In the above embodiment, the protective sleeve 22 is a cylindrical body. However, the protective sleeve 22 may include a pair of halved members, and may have a cylindrical shape as a whole when the halved members are combined. In this case, it is not necessary to pass the protective sleeve through the optical drop cable in advance.
In addition, the end face cap 34 of the embodiment has a structure that can be opened and closed including a pair of halved pieces connected via a thin hinge portion, but can also be a cylindrical body from the beginning. In this case, it is passed through an optical drop cable in advance.
The optical connector of the embodiment is a jacket gripping SC connector, but is not limited to the jacket gripping type, and the type of the connector main body is not particularly limited, and an appropriate type can be used.
Further, in the embodiment, a single optical drop cable is targeted, but an optical drop cable with a small number of cores such as a two-fiber optical drop cable can be targeted.

(A) The figure which shows the initial stage of the operation | work process at the time of obtaining the linear connection part structure of the optical drop cable of one Example of this invention, (B) is an AA expanded sectional view of (A). It is a figure which shows the step following FIG. (A) is a figure which shows the step following FIG. 2, (b) is BB expanded sectional drawing of the principal part of (a). (A) is a figure which shows the step following FIG. 3, (b) is CC expanded sectional drawing of the protective sleeve of (b). It is a figure which shows the step following FIG. FIG. 6 is a stage subsequent to FIG. 5, showing an appearance of a connection completion state. It is sectional drawing which shows an example of the optical drop cable made into the object in an Example. An example of the linear connection part structure of the conventional optical drop cable is shown, (A) is a perspective view explaining an internal structure, (B) is a side view explaining the condition which covers a protective sleeve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Optical drop cable 12 Optical fiber core wire 13 Strength member 14a, 14b Resin coating | cover 14c Constriction part 15 Optical cable 16 Support line 22 Protective sleeve 22a Circumferential groove 23 Peripheral groove member 23a Perimeter groove 25 SC connector (optical connector)
26 Adapter 27 Outer gripping portion 28 Connecting sleeve (support wire fixing means)
31 Base member 32 Cable gripping portion 32a Slit 33 Tape winding (fixing means)
34 Terminal cap 35 Thin-walled hinge part 36, 37 Half piece 36a, 37a Projection 36b, 37b Projection 37c Engagement claw

Claims (7)

An optical drop cable linear connection structure in which an optical cable part and a support line are integrated,
A pair of optical connectors attached to the ends of the optical cables on both sides to be connected are connected to each other, the optical connectors in the connected state are fixed to an elongated base member, and cable gripping portions provided on both sides of the base member Grip the optical cables on both sides with the support wires, and fix the support wires on both sides with the support wire fixing means. Cover the optical connector, cable gripping portion and support wire fixing portion with a cylindrical protective sleeve. An optical drop cable linear connection structure characterized in that both end portions of the sleeve are covered with end caps for closing the openings of the protective sleeve.   2. The optical drop cable according to claim 1, wherein optical connector portions on both sides connected to each other and support wire portions on both sides fixed to each other are provided along the elongated base member. Straight connection structure.   2. The optical drop cable linear connection structure according to claim 1, wherein the protective sleeve is composed of a pair of halved members and has a cylindrical shape as a whole when the halved members are combined.   2. The light according to claim 1, wherein the end face cap is composed of a pair of halved pieces connected by a thin-walled hinge portion, and the edges of the end caps are engaged when the halved pieces are closed. Drop cable straight connection structure.   A projecting strip that is formed in a cylindrical shape through which the optical drop cable is inserted at both end positions of the base member and has a circumferential groove on the outer surface, and is fitted on the inner surface of the terminal cap to the circumferential groove of the circumferential groove member. The linear connection part structure of the optical drop cable of Claims 1-4 characterized by the above-mentioned.   6. The straight connection structure of an optical drop cable according to claim 5, wherein the circumferential groove member is integral with the base member.   The optical drop according to claim 1, wherein a circumferential groove is formed in the vicinity of both ends of the protective sleeve, and a protrusion is formed on the inner surface of the terminal cap to fit into the circumferential groove on the outer periphery of the protective sleeve. Cable straight connection structure.

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