JP2000187119A - Optical connection box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the workability of various kinds of work in an optical fiber housing section of an optical connection box and to prevent optical fibers from being damaged during the work. SOLUTION: An extra length housing tray 10 which is drawable from a casing is housed in the optical fiber housing section of the optical connection box. The excess length housing tray 10 has a water-proof treatment section 12 which provides hermetic water stopping of an optical cable leading-in hole formed at the casing when the excess length housing tray is housed into the optical fiber housing section, an optical cable clamping section 13 which fixes the terminal of the optical cable 12 led into the optical fiber housing section, a tension member fixing section 14 which anchors the tension member drawn out of the terminal of the optical cable 21 and an excess length housing section 15 which curves the extra length of the optical fibers 22 drawn out of the terminal of the optical cable 1 and houses the excess length.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical connection box for connecting an optical fiber and a metal cable via a photoelectric converter for converting an optical signal and an electric signal in two directions or one direction.

[0002]

2. Description of the Related Art As shown in FIG. 4, in recent years, in an optical fiber communication network, an optical cable 5 is connected via an optical connection box 50.
It has been proposed to connect the optical fiber drawn out of No. 1 with a metal cable 52 on the communication terminal device side. In the optical connection box 50, although not shown, a photoelectric conversion unit, an optical fiber storage unit for storing an optical fiber drawn out at the end of the drawn-in optical cable 51, and a metal core drawn out at the end of the drawn-in metal cable 52 It has a metal termination to house the wire. In addition, the metal termination accommodates a number of components such as a gripping component for fixing a metal cable and a connector for connecting a metal core wire to a photoelectric conversion unit.

When storing optical fibers in the optical fiber storage portion of the optical connection box 50 or performing various operations such as switching connection to the already stored optical fibers or optical cables, the optical fiber is required. Since the inside of the storage section is narrow, workability is poor in the work where the hand is put here. Therefore, an optical cable gripping component such as a bracket for gripping and fixing the optical cable terminal pulled into the optical fiber housing portion, and a tension member fixing component such as a bracket for fixing and retaining the tension member exposed at the optical cable terminal, The components stored in the optical fiber storage unit are individually pulled out of the housing to perform the operation, and after the operation is completed, the components are returned to the optical fiber storage unit.

[0004]

However, there are the following problems in performing such an operation. That is, the optical cable pulled into the optical fiber storage section is
Since it is fixed by the waterproofing part in the optical cable lead-in hole of the optical connection box, in order to pull out the optical cable gripping part and the tension member fixing part out of the optical connection box, it is necessary to place the parts between these parts and the waterproofing part. It is necessary to ensure a radius of curvature of the drawn optical fiber that does not affect the optical transmission characteristics. Therefore, space and work are required for processing the extra length of the optical cable. In addition, it is necessary to secure the bending radius of the optical fiber between the optical cable gripping component or the tension member fixing component and the extra length storage component, and the optical fiber is pulled out from the extra length storage component. Therefore, it is necessary to store the pulled-out optical fiber in the extra-length storage component again, which is troublesome. In particular, an optical fiber drawn from an optical cable is easily affected by an external force that affects optical transmission performance, such as being damaged by sudden bending or the like. For this reason, an optical fiber that is not stored in the extra-length storage part needs to be carefully handled so that its bending radius is always kept at a predetermined value or more, and it is difficult to improve workability.

The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the workability of various operations in an optical fiber storage unit and prevent the optical fibers from being damaged during the operations.

[0006]

An object of the present invention is to provide an optical fiber housing for storing an extra length of an optical fiber drawn from an optical cable, a metal cable termination to which the drawn metal cable is connected, A photoelectric conversion unit that converts one of an optical signal transmitted by the metal cable and an electric signal transmitted by the metal cable to the other, an electric signal input / output to / from the photoelectric conversion unit, and an electric signal transmitted to the metal cable. And an electric signal conversion unit containing a plurality of card-like electric signal conversion parts for carrying out conversion between them, and an optical connection box containing the same in a housing. A retractable extra length storage tray is stored, and the extra length storage tray is formed in the housing when the extra length storage tray is stored in the optical fiber storage portion. A waterproofing section for sealing and stopping the optical cable lead-in hole, an optical cable gripping section for fixing an optical cable terminal pulled into the optical fiber housing section, a tension member fixing section for retaining a tension member pulled out from the optical cable terminal, The optical connection box is characterized in that the optical connection box is provided with an extra-length storage section for storing the extra length of the optical fiber drawn from the optical cable terminal in a curved state. The waterproofing section, the optical cable grip section, the tension member fixing section, and the extra length storage section are provided on the same rigid bottom plate, and the optical cable grip section and the tension member fixing section are provided with the extra length. Preferably, it is arranged close to the side of the storage section.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. 1 to 3 show an embodiment of the optical connection box of the present invention. The optical connection box of the present embodiment is, for example, a PDS (Passive
In a Double Star) type optical access system, a function to receive an optical signal transmitted by an optical cable, convert it to an electric signal suitable for a communication terminal, and output it, and convert the electric signal transmitted from the terminal via a communication line to an optical signal A device having at least one of a function of transmitting the data to an optical cable, that is, a device used as a so-called ONU (Optical Network Unit), can have a configuration as shown in FIG. 3, for example. The optical connection box shown in FIG. 3 is waterproof and has a housing 7 having a lid 8 that can be freely opened and closed. It is generally configured to house a metal cable termination portion 2, a photoelectric conversion portion 3, an electric signal conversion portion 6, a battery 4, a power supply portion 5, and the like, which are used in an aerial optical cable or in a building into which an optical cable is drawn. It is used by installing it on the like.

The photoelectric conversion section 3 converts bidirectionally an optical signal transmitted by the optical fiber and an electric signal transmitted by the metal cable. An electric signal conversion unit 6 is connected to the photoelectric conversion unit 3, and performs bidirectional conversion between an electric signal converted by the photoelectric conversion unit 3 and a communication signal transmitted to a metal cable. A plurality of line cards 6a, which are card-like electric signal conversion parts for one line or a specific plurality of lines, are stored. The line cards 6a are inserted and supported between a plurality of support plates provided in the electric signal conversion unit 6, and are arranged in parallel with each other. In the optical connection box having such a configuration, the lid 8 which can be freely opened and closed is generally opened at the time of work such as line switching and expansion.
Work is performed using the lid 8 as a work table. When the line card 6a is exchanged, the entire electric signal converter 6 is pulled out of the housing 8, or the ceiling 7a of the housing 7 is opened to take out and store the line card 6a.

The optical fiber storage section 1 stores an extra-length storage tray 10 that can be pulled out of the housing 7. FIG.
2 and 3 show an example of the extra-length storage tray 10. FIG. 1 is a plan view and FIG. 2 is a perspective view of a main part. The extra-length storage tray 10 is schematically configured by arranging a waterproofing section 12, an optical cable grip section 13, a tension member fixing section 14, and an extra-length storage section 15 on a bottom plate 11.
The bottom plate 11 is preferably made of a rigid material such as polypropylene (PP), has a substantially rectangular shape, and is formed in the optical fiber storage section 1 according to the internal structure of the optical connection box in which the extra length storage tray 10 is stored. Any suitable shape that can be stored can be used.

When the extra length storage tray 10 is stored in the optical fiber storage portion 1 of the housing 7, it is disposed near the optical cable lead-in hole 30 formed in the housing 7, and
The waterproofing portion 12 is provided on the edge portion of the optical disc 1 at a position where it can be engaged with the optical cable lead-in hole 30. The waterproofing part 12 is engaged with the optical cable lead-in hole 30 of the housing 7,
An appropriate configuration can be adopted as long as the optical cable 21 can be pulled into the extra-length storage tray 10 from the optical cable lead-in hole 30 and the optical cable lead-in hole 30 can be sealed and watertight. Waterproofing section 12 in the present embodiment
The bush 12a engages with the optical cable lead-in hole 30 so that the optical cable 21 penetrates in a watertight manner, and a bush receiver 12b is provided on the bottom plate 11. The bush receiver 12b is formed by integrally forming a pair of planar-shaped substantially U-shaped fixing members on the bottom plate 11 integrally with the bottom plate 11. On the other hand, the bush 12a is
Has a through hole 12c penetrated in a watertight manner, one end of which is formed to engage with the optical cable lead-in hole 30 in a watertight and detachable manner, and the shape of the remaining portion is watertight in the bush receiver 12b. And is detachably fixed. The bush 12a is preferably formed using a rubber hardness of 20 or less or a gel-like elastic member.
In the present embodiment, the bush 12a has a through hole 12c.
, Each of which has a split shape having
The optical cable 21 can be pulled into the extra-length storage tray 10. In the waterproofing section 12 having such a configuration, the end of the optical cable 21 is cut obliquely so as to be tapered, so that the bush 1 is cut.
2a can be easily inserted into the through hole 12c. Then, the bush 12a is fixed to the bush receiver 12b, and when the extra length storage tray 10 is inserted into the housing 7, one end of the bush 12a is positioned in the optical cable drawing hole 30 so that the extra length storage tray 10 is The bush 12a is pushed into the optical cable lead-in hole 30 by a thrust fixed to the housing 7 with bolts or the like, so that waterproof performance can be obtained.

In this embodiment, the optical cable 21 drawn from the waterproofing section 12 onto the extra length storage tray 10 is used.
A sheath or the like is removed from the tip over an appropriate length as needed, and an optical fiber (in the present embodiment, an optical fiber core, hereinafter simply referred to as an optical fiber) is removed from an optical cable terminal.
22, and a tension member (not shown) is in a pulled-out state. At the tip of the optical fiber 22,
The optical connector 23 is attached, and can be connected to the photoelectric conversion unit 3 provided adjacent to the optical fiber storage unit 1. The optical connector 23 is a so-called SC type optical connector (Sibgle Fiber Coupl) defined in JIS C5973 or the like when the optical fiber 22 is a single fiber.
ingOptical Fiber Connector) can be preferably used. When the number of optical fibers 22 is multi-core, JIS C5
So-called MT type optical connector (Me
chanically Transferable Optical Fiber Connector)
Can be preferably adopted.

In the extending direction of the optical cable 21 drawn in from the waterproof processing section 12, preferably, the optical cable gripping section 13 and the tension member 14 are moved closer to the side of the extra length storage section 15 described later. It is arranged in order from. The optical cable gripping portion 13 fixes the optical cable terminal, that is, the distal end portion of the sheath of the optical cable 21, and can employ an appropriate configuration as long as the optical fiber 22 and the tension member can be pulled out therefrom. The optical cable gripping portion 13 of the present embodiment includes a lower member 13a having a groove for accommodating the optical cable 21 on an upper surface, and a small upper member 13b fixed to the lower member 13a by screws (screw 13c). And screw 1
3c, the upper member 13b and the lower member 13
It is configured such that the sheath portion of the optical cable 21 in the groove can be gripped by the a and the a. Further, the upper member 13b is
When c is loosened, it rotates on the upper surface of the lower member 13a around the screw 13c to open the upper part of the groove, from which the optical cable 21 can be inserted into the groove. In the present embodiment, two grooves are formed in the lower member 13a, and the upper member 13b is arranged on each groove.

The tension member fixing portion 14 holds the tension member pulled out from the optical cable terminal gripped by the optical cable gripping portion 13 and an appropriate one as long as the optical fiber 22 pulled out from the same optical cable terminal penetrates. A configuration can be employed.
The tension member fixing portion 14 of the present embodiment has a cutout 14 at the center in the thickness direction along a plane parallel to the bottom plate 11.
A block-shaped member provided with a is used. A groove for accommodating the optical fiber 22 pulled out from the optical cable grip 13 is preferably formed in the cutout portion 14a. Further, through holes 14b through which the tension members pulled out from the optical cable gripping portion 13 are inserted are provided at upper and lower portions with the notch portion 14a interposed therebetween, and the tension members inserted here are screws 14c and the like. Is fixed by an appropriate fixing means.
In the present embodiment, the tension member fixing portion 14 is formed integrally with the optical cable grip portion 13, and the lower member 13 a of the optical cable grip portion 13 and the lower portion of the cutout portion 14 a of the tension member fixing portion 14 are continuous. Is formed. In the tension member fixing portion 14 of the present embodiment, the planar shape of the portion where the cutout portion 14a is formed is substantially L-shaped, and the tension member fixing portion 14 has two sets of tension members pulled out from two optical cable terminals. In this case, a retaining process can be performed. Also, the optical cable gripping portion 13 and the tension member fixing portion 14
When the work is not performed on, it is preferable to cover a detachable cover (not shown) corresponding to these shapes from above.

In the present embodiment, the extra length storage portion 15 is provided at a position slightly closer to the short side (leftward in FIG. 1) than the center of the bottom plate 11 in the long side direction. The extra length storage portion 15 is an optical fiber 22 that penetrates the tension member fixing portion 14.
Can be adopted as long as it is housed and the leading end is guided in the direction of the photoelectric conversion unit 3 of the housing 7 while maintaining a curvature radius in a range that does not affect the optical transmission performance. . Usually, the radius of curvature in a range that does not affect the optical transmission performance is 30 mm or more. The extra length storage section 15 of the present embodiment is constituted by a partition wall integrally formed with the bottom plate 11 at a constant height on the bottom plate 11, and the optical fiber 22.
An outer wall 15a formed in an elliptical shape to wind the optical fiber 22 along the outer wall 15a, and an inner wall 15b for guiding the optical fiber 22 wound along the outer wall 15a to the outside of the outer wall 15a. A guide wall 15c for guiding the optical fiber 22 from the member fixing portion 14 into the outer wall 15a and guiding the optical fiber 22 from the inside of the outer wall 15a to the photoelectric conversion portion 3 is provided. Further, eaves 15d extending inward from the upper end of the outer wall 15a are formed at intervals so that the optical fiber 22 does not pass over the outer wall 15a. In the present embodiment, the plate-like cover 1 is mounted on the upper end surfaces of the outer wall 15a and the guide wall 15c.
5 e is provided so as to be openable and closable with respect to the extra length storage portion 15, thereby covering the upper surface of the entire extra length storage portion 15.

According to this embodiment, the optical fiber housing 1
The extra-length storage tray 10 including the waterproofing part 12, the optical cable gripping part 13, the tension member fixing part 14, and the extra-length storage part 15 can be pulled out from the optical fiber storage part 1. Therefore, when these components are pulled out of the optical connection box or stored in the original position, the distance between the components does not change, and therefore, the extra length of the optical cable 21 or the optical fiber 22 is increased due to the work. No fluctuation occurs. In addition, extra storage tray 10
Is disposed in the vicinity of the cable lead-in hole 30 formed in the housing 7, and the waterproof processing part 1 for sealingly stopping water in the cable lead-in hole 30.
2 is fixed to the extra-length storage tray 10, and the thrust for fixing the extra-length storage tray 10 to the housing 7 allows the optical cable lead-in hole 30 to stop water. At this time, even if the extra-length storage tray 10 is pulled out or re-stored in the housing 7, since the optical cable 21 is fixed to the waterproofing section 12, the optical fiber 22 bent and stored in the extra-length storage tray 10 is used. Does not cause a variation in the bending radius, and a preferable bending radius is stably maintained. Therefore, no extra work or space for extra length processing, which has been required each time various operations are conventionally performed, is not required, which contributes to improvement of workability and miniaturization of the apparatus. In addition, since the components on the extra length storage tray 10 are pulled out collectively, the bending radius of the optical fiber 22 does not change during the pulling out operation or the re-storing operation. Therefore, there is no fear of damaging the optical fiber 22 during work, and workability can be improved. Extra storage tray 10
When manufacturing the same, it is possible to integrally or partially form all of the above components on the same bottom plate 11, thereby reducing the number of components and reducing the cost.

The waterproofing section 12 on the bottom plate 11
Optical cable gripper 13, tension member fixing part 14,
The arrangement of the extra length storage section 15 is not limited to the arrangement of the present embodiment, and can be changed as appropriate. However, it is necessary to design the optical fiber 22 so that the optical fiber 22 is not bent to affect the optical transmission performance. In the present embodiment, the bush receiver 12b and the extra length storage section 15 of the waterproofing section 12 are formed integrally with the bottom plate 11, but these are separately fixed to the bottom plate 11 by appropriate fixing means. Is also good. In general, the extra length storage tray 10 is
The trays are stored in stages, but a plurality of extra-length storage trays 10 can be stacked in multiple stages and stored in the optical fiber storage unit 1.

[0017]

As described above, according to the optical connection box of the present invention, the extra-length storage tray provided with a necessary portion in the optical fiber storage section can be pulled out from the optical fiber storage section, and the entirety is provided. Are collectively pulled out, so that the bending radius of the optical fiber does not change during the pulling-out operation or the re-storage operation. Therefore, there is no fear of damaging the optical fiber during the operation, and the workability can be improved. Also,
No extra work or space is required for extra processing,
The workability can be improved, and the size of the device can be reduced.

[Brief description of the drawings]

FIG. 1 shows an embodiment of an optical connection box of the present invention, and is a plan view of an extra-length storage tray.

FIG. 2 is a perspective view of a main part of the extra-length storage tray of FIG.

FIG. 3 is a schematic configuration diagram illustrating an example of an optical connection box.

FIG. 4 is an explanatory diagram showing an example of a communication system using an optical junction box.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical fiber storage part, 3 ... Photoelectric conversion part, 7 ... Housing, 1
0: extra storage tray, 11: bottom plate, 12: waterproofing part,
13: Optical cable gripping part, 14: Tension member fixing part, 15: Extra length storage part, 21: Optical cable, 22: Optical fiber, 30: Optical cable lead-in hole

Claims (2)

[Claims] An optical fiber storage part (1) for storing an extra length of an optical fiber (22) drawn from an optical cable (21), and a metal cable termination part (2) to which the drawn metal cable is connected. A photoelectric conversion unit (3) for converting one of an optical signal transmitted by the optical fiber and an electric signal transmitted by the metal cable to the other, an electric signal input / output to / from the photoelectric conversion unit, and the metal cable Electrical signal conversion part (6) containing a plurality of card-shaped electrical signal conversion parts (6a) for converting between electrical signals transmitted to
In the optical connection box in which the extra length storage tray (10) that can be pulled out from the enclosure is stored in the optical fiber storage portion, the extra length storage The tray has a waterproofing section (12) for sealing and stopping the optical cable lead-in hole (30) formed in the housing when the extra-length storage tray is stored in the optical fiber storage section, and the optical fiber storage section. An optical cable gripping portion (13) for fixing the pulled-in optical cable terminal, a tension member fixing portion (14) for holding the tension member pulled out from the optical cable terminal, and an extra length of the optical fiber drawn out from the optical cable terminal. Extra length storage section to store
(15) An optical connection box, comprising: 2. The optical cable holding section, the optical cable holding section, the tension member fixing section, and the extra length storage section are provided on the same rigid bottom plate (11). The optical connection box according to claim 1, wherein a member fixing portion is disposed adjacent to a side portion of the extra length storage portion.