JP3524067B2 - Optical distribution box - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical distribution box for accommodating a branch portion of an optical cable. 2. Description of the Related Art When connecting an optical cable to a device, it is necessary to take out a tape core from the optical cable and branch the tape core into a single core. It is difficult to branch a tape core into a single core at the site of connection with equipment.
Therefore, usually, the FO cord or the branch core having a form in which one side of the tape core is branched into a single core is connected to the tape core taken out from the optical cable, so that the tape core is branched into the single core. Returning to work. The branch portions including these connection points are housed in a box called an optical wiring box with each core wire or the like having a predetermined extra length. FIG. 2 shows an example of a two-core FO cord with a single-end optical connector. Reference numeral 7 denotes an SC connector, 8 denotes a mark band for identification, 9 denotes a single-core cord in which a single-core wire is provided with a reinforcing material such as Kevlar, and a tube is covered on the outside thereof, and 10 denotes a reinforcing tube for protecting a branch portion. , 11 indicate a two-core tape code. FIG. 2B shows a cross section of the two-core tape cord. 2
A reinforcing material 13 such as Kevlar is vertically attached to the periphery of the core tape 12, and a jacket 14 is covered on the outside thereof.
FIG. 3 shows the inside of the branch portion of the two-core FO code. Single core wire 1
5, the reinforcing material 13 such as Kevlar is cut, so that the single core 15 may be stressed at the branch portion. Is fixed to a reinforcing plate 26, and the inside of the reinforcing tube is filled with a resin 19 such as epoxy and is solidified. The FO cord is designed to sufficiently withstand the tension of tension, such as the above-described structure of the branch portion. However, the drawback is that the FO cord is slightly bulky because of a reinforcing pipe and a reinforcing material. is there. FIG. 4 shows a branch core wire with a one-end connector.
Reference numeral 20 denotes a two-core tape, 21 denotes a heat-shrinkable tube for protecting a branch portion, 22 denotes a single-core wire covered with a transparent nylon tube, and 23 denotes an SC connector. Branch 2 of branch core wire
In 4, a transparent nylon tube over a single core wire,
A heat-shrinkable tube 21 containing a hot-melt adhesive is placed over the two-core tape core wire, heat-shrinked and fixed. In the case of a branch core, a transparent nylon tube is placed over the single core,
Since the color of the coated core wire is visible, it can be identified by the color. In the case of the FO code, it is not necessary to attach a necessary identification mark band. In addition, since no reinforcing material such as Kevlar is used, a thin and compact finish can be achieved. [0005] In the case of the FO cord, the single-core wire is also protected by a reinforcing material or a sheath, and even if it is exposed to a somewhat strong light, the transmission of noise or the like may occur. No problem arises. However, in the case of the branch core, the single core is covered with a transparent nylon tube only, and optically, it is similar to the bare core, so if it is exposed to strong light such as a photo flash, noise will be generated For example, a problem may occur in transmission. In order to make the optical wiring box compact, when a branch core is used for the branch portion, there is no problem when the optical wiring box door is closed, but when the wiring box door is open, The single core wire is covered with a transparent nylon tube only, and is optically bare and in a similar state. The single core wire is exposed to strong light, which may cause a problem in transmission such as generation of noise. SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and optically only covers the transparent tube even if the door of the optical wiring box is opened. , Strong light etc. does not directly hit the bare single-core wire,
Provides a compact optical distribution box that is obtained as a result of devising the use of branch core wires without worrying about transmission problems such as noise generation, and is provided inside the optical distribution box. a light shielding plate between the core wire and the optical wiring box door is provided, the light shielding plate is attached to the tip of the column, removal own
It is fixed by existing fixing means . There is no need to be particular about the material of the light-shielding plate, and any material can be used, such as a black-colored plastic plate, which can directly block light from hitting the branch core wire. FIG. 1 shows an example of an embodiment of the present invention, the contents of which will be described with reference to the drawings. Reference numeral 6 denotes a box of the optical wiring box, and reference numeral 3 denotes a door that can be freely opened and closed. The door has been described as being openable and closable using a hinge, but may be attached and detached by covering the door with a box with a sliding door. A branch core wire is provided inside the box 6, and a black colored plastic plate is provided between the door 3 and the branch core wire as a light shielding plate. That is, inside the box,
The branch core, extra length storage tray 5, and the SC adapter 4 are stored, and the single core of the branch core is covered with a transparent nylon tube on both sides of the SC adapter. The four corners of the light-shielding plate 1 are bolted to the ends of four light-shielding plate mounting posts 2 provided vertically on the bottom of the box so that the portion 22 in the state can be covered with the light-shielding plate 1.
5 and fixed. The method of fixing the light-shielding plate is not limited to bolting. However, when the light-shielding plate is bolted to the tip of the support, the light-shielding plate obstructs the work due to wiring replacement work or the like. In such a case, it is convenient that it can be easily removed and attached after work. According to the present invention, since the optical wiring box is provided with the light shielding means between the door of the box and the branch core, even if the operation is performed with the door of the optical wiring box opened. There is no longer any need to worry about the optical fiber being exposed to strong light. As a result, the bulky F
A compact branch cable can be used without using an O-code, and the optical distribution box can be made compact.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an example of an optical wiring box according to the present invention, wherein (a) is a cross-sectional plan view, (b) is a cross-sectional view taken along the line BB, and (c).
FIG. 3 is a cross-sectional view of a cross section taken along the line CC, and FIG. FIG. 2A is an overall view of a two-core FO cord with a one-end connector. (B) is a sectional view of a two-core FO cord. FIG. 3 is a sectional view of a branch portion of the two-core FO cord. FIG. 4 is an overall view of a two-core branch core wire. [Description of Signs] 1 light-shielding plate 2 light-shielding plate mounting support 3 optical wiring box door 4 SC adapter 5 extra length storage tray 6 optical wiring box box 7 SC connector 8 identification mark band 9 single core cord 10 branching section Protective reinforcement tube 11 2-core FO cord 12 2-core tape core 13 Reinforcement 14 Jacket 15 Single core 16 Reinforcement 17 Reinforcement tube 18 SC connector 19 Epoxy resin 20 2-core tape core 21 Heat-shrink tube 22 Transparent nylon Single-core wire 23 covered with tube SC connector 24 Branch portion of 2-core tape core wire 25 Bolt 26 Protective plate

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuya Iwamoto 1-226 Higashi-Chome, Komaki-shi, Aichi Prefecture Inside (72) Inventor Makoto Tominaga 1-226, Higashi 1-chome, Komaki-shi, Aichi Nippon Telegraph and Telephone Corporation (72) Inventor Hideyuki Kondo 1-226 Higashi 1-chome, Komaki City, Aichi Prefecture Nippon Telegraph and Telephone Corporation (56) References JP-A-60-162208 (JP, A) JP-A 8-179139 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G02B 6/00 G02B 6/24

Claims (1)

(57) [Claim 1] In a box body having a door that can be opened and closed, a branch core wire in which a single core wire is covered with a transparent tube is provided, and a light shielding plate that covers at least the transparent tube is provided. The light shielding plate is provided between the door and the branch core wire, and is attached to a tip of a column.
An optical distribution box fixed by detachable fixing means .