JP2801204B2 - Method of forming SZ slot optical fiber cable rear branch connection - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method of forming a rear branch connection of an SZ slot optical fiber cable.

[Prior Art] A groove of a predetermined length is spirally formed in the outer periphery of a spacer in a circumferential direction toward the length direction thereof, and a groove is formed in a spiral shape continuously in the opposite direction. hand
There has been proposed an SZ slot optical fiber cable in which an SZ slot formed of an SZ-shaped groove is provided, an optical fiber core wire is housed in the SZ slot, and a sheath is coated on the outer periphery of the spacer.

In the branch connection of such an SZ slot optical fiber cable, conventionally, the SZ slot optical fiber cable is once cut to perform the branch connection.

However, such a method of forming the branch connection portion has a problem that optical fibers that do not need to be branched and connected are also cut, and the subsequent connection work is troublesome.

For this reason, a method of forming a post-branch connection portion in which the optical fiber cores that do not need to be branched of the spacer having the SZ slot are not cut together and the optical fiber cores that need to be branched can be cut and branched. There is a demand for the practical use of.

[Problems to be Solved by the Invention] However, in the case where the rear branch connection portion of the SZ slot optical fiber cable is formed, there is a problem that it is difficult to take out the optical fiber because the slot has the SZ shape. . Further, when the SZ slot optical fiber cable is laid along a wall of a building or the like, even if the sheath of the SZ slot optical fiber cable is stripped and a predetermined optical fiber core is taken out from the SZ slot of the spacer. If the slot faces a wall or the like on the back side of the spacer, there is a problem in that it is difficult to take out the optical fiber core.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for forming an SZ-slot optical fiber cable rear-branch connection portion that can easily take out an optical fiber core from an SZ-type slot.

Another object of the present invention is to provide a method of forming an SZ-slot optical fiber cable rear-branch connection part that can easily take out a required optical fiber core even if there is an obstacle on the opposite side of the working position. It is in.

Means for Solving the Problems To explain the means of the present invention for achieving the above object, according to the present invention, an optical fiber core is accommodated in an SZ slot of a spacer, and a sheath is coated on the outer periphery of the spacer. In the method of stripping the sheath of the SZ slot optical fiber cable formed to form a post-branch connection portion, the sheath of the SZ slot optical fiber cable is inverted at a pitch of the SZ slot at a place to be post-branch connection. The spacer is exposed at a length equal to or more than 1/2 of the pitch of the SZ slot to expose the spacer without cutting, and the exposed portion of the spacer sags the optical fiber core wire in the SZ slot from the SZ slot. Take out and cut,
A branch optical fiber core is connected to a cut end of the optical fiber core.

[Operation] In this way, the SZ slot is exposed together with the spacer at a length of 1/2 slot pitch or more including the inverted portion of the pitch, and the required optical fiber core is formed at the inverted portion of the pitch. Take out from the SZ slot of the spacer,
The optical fiber can be easily taken out, and the taken out optical fiber has slack, so that the cutting is easy. Also, including the inversion of the SZ slot pitch
When stripping the sheath with a length of 1/2 slot pitch or more,
Even if that part is adjacent to a wall, etc., the required optical fiber core to be branched will be located on the near side or up and down in any part of the sheath stripping section, and there is an obstacle on the opposite side of the working position Even if it is, a required optical fiber core can be easily taken out.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG. 1 to FIG. As shown in the figure, the SZ slot optical fiber cable 1 is provided with a sheath 2 of the SZ slot optical fiber cable 1 and a spacer 3 therein at a place to be branched and connected.
Including the reversal portion 4A of the pitch of the SZ slot 4, the spacer 3 is peeled off at a length of 1/2 or more of the SZ slot pitch to expose the spacer 3 without cutting.

In this way, as shown in FIGS. 3 and 4, all the slots 4 always face the working side or the upper and lower sides, and there is no problem even if the building wall 5 exists on the side opposite to the working side. The required optical fiber core wire 6 can be taken out from the SZ slot 4. Also, the inverted part of SZ slot 4
When the spacer 3 is exposed at a pitch of 1 / 2SZ slot or more at a location including 4A, the optical fiber core 6 exposed from the SZ slot 4 comes out of the spacer 3 with a slack. The cutting can be performed without disturbing the spacer 3.

The cut optical fiber core 6 is connected to the branch optical fiber core 8 of the branch optical fiber cable 7 by a fusion splicing method, a V-groove connection method, or the like to form a core fiber connecting portion 9. The extra length 10 of the optical fiber 6 and the optical fiber 8 thus branched and connected together with the optical fiber connecting part 9 is stored in a two-part extra length storage case 11. Are stored in the connection box 12. The penetrating portions of the SZ slot optical fiber cable 1 and the branch optical fiber cable 7 at both ends of the connection box 12 are hermetically sealed by a split end plate 13 and a sealing material 14. In the connection box 12, the sheath ends of the SZ slot optical fiber cable 1 and the branch optical fiber cable 7 are fixed to the connection box 12 by fixing brackets 15. Reference numeral 16 denotes a tension member in the spacer 3.

[Effects of the Invention] As described above, according to the method of forming the rear branch connection portion of the SZ slot optical fiber cable according to the present invention, the following excellent effects can be obtained.

(B) The SZ slot is 1/2 including the reversal part of the pitch.
Since it is exposed together with the spacer with a length equal to or longer than the slot pitch, if the required optical fiber core is taken out from the SZ slot of the spacer at the inversion of the pitch, the optical fiber core can be easily taken out. Since the optical fiber taken out together with the cable has a slack, there is an advantage that the optical fiber can be easily cut.

(B) In addition, 1/2 including the inversion of the SZ slot pitch
If the sheath is stripped with a length equal to or longer than the slot pitch, the required optical fiber core to be branched must be located on the near side or up and down in any part of the sheath stripping section even if that part is adjacent to a wall etc. Therefore, even if there is an obstacle on the opposite side of the working position, there is an advantage that the required optical fiber can be easily taken out.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a sheath stripped portion of an SZ slot optical fiber cable in one embodiment of a method of forming an SZ slot optical fiber cable rear branch connection portion according to the present invention, and FIG. 2 is a rear branch connection portion of the present embodiment. 3 and FIG. 4 are a sectional view taken along line AA 'and a sectional view taken along line BB' of FIG. 1 .... SZ slot optical fiber cable, 2 .... sheath,
3 ... spacer, 4 ... SZ slot, 4A ... inverted part,
5 ... wall, 6 ... optical fiber core wire, 7 ... branch optical fiber cable, 8 ... branch optical fiber core wire, 9 ... core wire connection part, 10 ... extra length part, 11 ... extra length Storage case, 12 ……
Connection box.

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Morinobu Mizutani 1-3-1 Uchisaiwaicho, Chiyoda-ku, Tokyo Inside Tokyo Electric Power Company (72) Inventor Keiichi Ito 6 Yawata Kaigandori 6 Ichihara-shi, Chiba Furukawa Electric Chiba Works Co., Ltd. (72) Inventor Tadashi Ujino 6 Yawata Kaigandori, Ichihara-shi, Chiba Furukawa Electric Co., Ltd. (72) Inventor Etsuo Tanabe 6 Yawata Kaigandori, Ichihara-shi, Chiba Furukawa Electric Inside the Chiba Works (72) Inventor Shigeru Tategami 6 Yawata Kaigandori, Ichihara-shi, Chiba Prefecture Inside the Furukawa Electric Co., Ltd. Chiba Works (56) References JP-A-60-211408 (JP, A) JP-A-63-132207 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G02B 6/00 336 G02B 6/24 G02B 6/44 366

Claims (1)

(57) [Claims] 1. A method of forming a rear branch connection portion by stripping the sheath of an SZ slot optical fiber cable in which an optical fiber core is accommodated in an SZ slot of a spacer and a sheath is coated on an outer periphery of the spacer. At the point where the post-branch connection is to be made, the sheath of the SZ slot optical fiber cable is peeled off at a length equal to or more than 1/2 of the SZ slot pitch, including the inverted portion of the pitch of the SZ slot, to cut the spacer. The optical fiber core wire in the SZ slot is taken out of the SZ slot with a slack at the exposed part of the spacer and cut, and a branch optical fiber core wire is cut at the cut end of the optical fiber core wire. A method for forming an SZ-slot optical fiber cable rear branch connection portion, comprising: