JPS6151766B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a connection box for an armored submarine optical fiber cable that is easy to assemble onboard a ship, has high corrosion resistance, and has an electrical transmission line such as a power supply line, and is tensile strength, pressure resistant, and airtight. It is related to.

Japanese Patent Application No. 56-44147 discloses an unknown prior art of a connection box for an armored submarine optical fiber cable that facilitates on-board assembly. Here, as shown in FIG. 1, the pressure tube constituting the connection box body of the submarine optical fiber cable 1 is divided into a plurality of parts, and some of the movable pressure tubes 13 are connected to other fixed pressure tubes 11. To enable sliding on an outer circumferential surface, thereby allowing optical fiber core wires to be connected and a connecting box to be assembled in a short time. As shown in FIG. 2, an example of the structure of the armored submarine optical fiber cable 1 applied to the connection box of the armored submarine optical fiber cable 1 is as shown in FIG. Fiber core wire 3, cushioning material 4, metal pressure layer 5, internal tensile strength wire 6, insulation jacket 7
and a sheathing wire 8 spirally wound on the sheath 7
.

To assemble the connection box shown in FIG. 1, insert the submarine optical fiber cable 1 into the pressure-resistant end plate 9,
A watertight part is formed on the outer surface of the metal pressure-resistant layer 5 in the cable 1 by using an O-ring 14, adhesive or soldering, and the internal tensile strength wire 6 is connected by adhesive or the like at the tapered opening of the pressure-resistant end plate 9. Fix it. Next, after fixing the outer wire 8 with the outer wire holding member 10 inserted into the end plate 9, the fixed pressure tube 11
is attached to the end plate 9, and the fixed pressure tube 11 is attached to the end plate 9.
And the exterior wire retaining bodies 10 are fixed to each other with nuts or bolts. Furthermore, a boot 12 made of a hard rubber material is attached from the cable 1 side, and the cable is secured on one side. Perform this operation on both ends of the opposing cable.

During connection work on board, after connecting the optical fiber cores 3 and center support 2 of opposing cables, store them in the space limited by both end plates 9, including the extra connection length, and pass them through in advance. Movable pressure tube 1
3 is slid over the fixed pressure tube 11 which has already been fixed to the cable retainer 10, and is sealed with the outer surface of the fixed pressure tube 11 using an O-ring 14 to maintain watertightness. Movable pressure tube 13 and fixed pressure tube 1
1 are fixed to each other by a set ring 15 and joint nuts 16 and 17 to complete the assembly.

As mentioned above, connecting boxes with this structure are assembled in a factory, which requires time-consuming processes such as securing the outer wire and creating a watertight part with the cable, and then being assembled on board the ship by connecting the optical fiber core wire and metal This simplifies the work by limiting it to the assembly of jigs.

However, in this structure, the cable sheath wire 8 and the connection box body, that is, the fixed and movable pressure tubes 11
13 and the voltage-resistant end plate 9 are not only mechanically connected, but also electrically connected, since metal conductors such as iron or steel are normally used for the cable sheath 8. It turns out. In such cases, when a potential distribution occurs in the cable laid under the seabed and each connection box due to tidal power generation, ground potential difference, inflow of external current, etc., current flows in and out between adjacent connection boxes. become. In this case, metal ions were dissolved in the connecting box on the side where the current flows, causing corrosion, which caused watertight breakdown and mechanical strength deterioration over time. Further, the metal pressure-resistant layer 5 within the cable is electrically coupled to the pressure-resistant end plate 9 and the pressure-resistant tubes 11 and 13, and these are electrically short-circuited to the external seawater and further to the earth. Therefore, when trying to electrically transmit the power supply current to the intermediate repeater of the transmission line, the monitoring signal of the terminal equipment, the meeting signal, etc. between the earth and the ground using the metal voltage-resistant layer in the cable. Because of the problem of ground faults in electrical signals in each connection box, it was necessary to insulate the entire electrical path of the connection boxes, including the metal voltage-resistant layer 5, from seawater.

Therefore, the object of the present invention is to provide an exterior submarine optical system that eliminates the above-mentioned drawbacks of corrosion and ground faults in metal pressure-resistant layers, has excellent corrosion resistance, and enables power transmission to repeaters or equipment monitoring signal transmission. The purpose is to provide a connection box for fiber cables.

In order to achieve this objective, the present invention divides the pressure tube into a plurality of parts and makes them openable and closable to maintain ease of connection on board the ship, and the outer periphery of the pressure tube of the connection box is made of a sleeve-shaped tube that is easily dismantled. By covering the cable with a plastic insulating layer, the metal voltage-resistant layer inside the cable is insulated from seawater, and the exterior retaining body and the pressure-resistant tube body are also electrically insulated.

More specifically, the present invention provides an interconnection of armored submarine optical fiber cables having an armored wire wound around the outer circumference of the cable and a metal pressure-resistant layer disposed inside the insulated cable jacket, or the armored submarine optical fiber cable. and a repeater, a pressure-resistant end plate fixed while maintaining watertightness with the metal pressure-resistant layer, a fixed pressure-resistant pipe fixed to the pressure-resistant end plate, and an outer circumferential surface of the fixed pressure-resistant pipe. Inside the connection box body, which is limited by a movable pressure-resistant tube that can slide, are the optical fiber connection parts of the opposing cables, the excess length of the optical fibers, and the lead wire connection parts such as power supply lines, repeater units, and relays. A waterproof bulkhead is installed to accommodate the connection part of the tail fiber core of the device.
Both sides of the voltage-resistant end plate are covered with insulating end plates that are bonded to the insulated cable jacket, and both sides of the voltage-resistant end plate are covered with the exterior seabed covering the insulating end face. An armored wire stopper having a through hole for the optical fiber cable is attached, an insulating sleeve is fitted to the outer circumferential surface of the armored wire stopper and the movable pressure tube, and the insulating sleeve and the insulated end plate are connected to the insulating end plate. The sleeves are connected at both ends, and at both ends of the insulating sleeve, an insulator is inserted between the insulating sleeve and the sheath wire stop, and a protective tensile tube is connected with a nut, and the protective tensile tube is connected to the insulation sleeve. A boot formed of a hard rubber material is attached so as to cover the outer peripheral surface of the sleeve, and covers the armored submarine optical fiber cable and the armored wire in the vicinity of the armored wire retention body. A flexible plastic resin material is injected into the inside of the boot.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 3 shows an embodiment of the invention, in which the first
The same parts as in the figure or FIG. 2 are given the same reference numerals. In FIG. 3, 18 is an insulating end plate, 19 is an insulating sleeve, and 20 is an insulating end plate 18.
and the cable jacket 7, 21 is a spacer,
Reference numeral 22 indicates a joint for disassembling and repairing the insulating layer, 23 indicates a protective tensile tube, 24 indicates an insulating ring, 25 indicates a tightening nut, 26 indicates a plastic resin, and the other parts are the same as those shown in FIG.

The assembly of this connection part is substantially the same as that described with reference to FIG. 1 up to the fixing and coupling of the pressure tubes. Furthermore, in the present invention, an insulating end plate 18 formed in advance from the same material as the cable sheath 7, for example, plastic such as polyethylene, so as to cover the pressure-resistant end plate 9, is inserted between the sheathing wire stop 10 and the pressure-resistant end plate 9. The scissors electrically insulate the armored wire 8 and the connection box body, thereby preventing the corrosive current flowing through the armored wire 8 from flowing out or flowing into the connection box. Further, the cable side end 20 of this insulating end plate 18 is bonded to the cable jacket 7 by molding or the like.

Further, the optical fiber core wire 3 is connected, and the remaining length of the connection is stored in a predetermined space between the opposing cable retaining parts that have already been prepared, and the central steel wire 2 is connected to the central steel wire retaining body 27 near the end plate 9. For example, when transmitting a signal between the central steel wire 2 and the metal pressure layer 5 of the cable, a lead wire 28 is used to connect the opposing central steel wires 2 and 2'. Further, when the metal voltage-resistant layer 5 is used for power supply to a repeater, the opposing voltage-resistant layers may be connected similarly using the lead wire 29. In addition, in order to prevent water from running into the cable due to a cable failure or the like, a waterproof bulkhead 30 is provided inside the fixed pressure tube 11, and the optical fiber core 3 and the central steel A watertight seal 31 made of rubber or plastic resin is applied to each of the wires 2 and lead wires 29 such as the power supply line.

After interconnecting the various members in the cable as described above, the movable pressure tube 13 is slid over the fixed pressure tube 11 that has already been fixed to the end plate 9, and the connection box is closed.
Settling 15 and joint nut 16,
Fixed and movable pressure tubes 11 and 13 by 17
are fixed to each other.

Next, spacers 21 are placed on the pressure tubes 11 and 13.
Then, a removable insulating sleeve 19 is placed over either one of the outer wire stoppers, and the same insulating material (polyethylene, etc.) as the insulating end plate 18 is used at both ends 22 of the insulating sleeve 19, and this end plate 18 is molded or welded. By melting and adhering them, the connecting box body made up of the pressure tubes 11 and 13 and the end plate 9 is insulated from external seawater and water is prevented from penetrating.

In the connection box configured in this way, the end plate 9 is electrically connected to the metal voltage-resistant layer 5 of the cable.
Since the voltage-resistant tubes 11 and 13 are insulated from external seawater and the ground, the problem of ground faults at the connecting box is solved even when the metal voltage-resistant layer 5 is used to supply power to repeaters or transmit monitoring signals. can.

Furthermore, since it is difficult to transmit the tension of the cables on both sides through the internal pressure tubes 11 and 13 because of the insulating layer 18, the inner diameter is slightly larger than the outer diameter of the insulating sleeve 19. A protective tensile tube 23 made of a material with excellent strength and high corrosion resistance against seawater, such as a copper-beryllium alloy, is placed over the insulating sleeve 19, and is electrically insulated from the outer wire stop 10. Insulation rings 24 made of plastic or porcelain insulators with high electrical insulation and excellent compression resistance, such as ceramic materials such as alumina, are sandwiched between both ends of the sheathing wire stop 10 to protect the tensile strength tube 23.
and the sheathing wire holding body 10 are fixed with a joint nut 25 and connected to each other. The rubber boot 12 as an end reinforcing agent is used by being fixed to a joint nut 25 as shown in FIG.

In addition, in order to strengthen the rigidity, especially the bending resistance, of the cable and sheathed wire in the vicinity of the sheathed wire tie-down body, and to prevent corrosion of the iron wire due to water permeation into the tie-down area, epoxy resin or polysulfide rubber is used before installing the boot. Preferably, a plastic resin material 26 having a flexibility of about 100 mL is injection molded.

As explained above, in the armored cable connection box according to the present invention, the metal pressure-resistant layer 5 inside the cable
Pressure-resistant end plate 9 and pressure-resistant tubes 11 and 13 connected to
The entire connection box body including the insulating layers 18 and 19
Since the metal voltage-resistant layer 5 is completely covered with the metal voltage-resistant layer 5, there is no ground fault to seawater or the earth at the connection box part, and the metal voltage-resistant layer is used to supply power to the repeater or transmit terminal equipment monitoring signals, etc. becomes possible.

Furthermore, in the present invention, since the insulating layers 18 and 19 can electrically insulate the sheathing wire 8 and its retaining body 9 from other metal bodies, contact corrosion of different metals between the connecting box body and the sheathing wire 8 can be avoided. Alternatively, it is possible to prevent the corrosive current flowing through the outer wire itself from flowing in and out of the connection box body, and seawater is blocked by the insulating layers 18 and 19, and the O-ring 14 inserted between the pressure tubes 11, 13 and the pressure end plate 9 is In addition to its effectiveness, it prevents water from penetrating into the connection box, making it corrosion resistant, watertight,
A connection box with extremely high airtightness can be realized.

If disassembly or reconnection is required on board for repairs, etc., move the joint nut 25 and boot 12 to the cable side, pull out the protective tensile tube 23 to either cable side, and then remove the insulating sleeve 1.
9 is dismantled and the insulating sleeve 19 is similarly pulled out to the cable side. Furthermore, the spacer 21 is removed, the joint nuts 16 and 17 are disassembled, the movable pressure tube 13 is opened to both sides, and a predetermined optical fiber core connection section is taken out and repaired and connected.

In addition, when replacing cables between connection boxes, the connection box can be divided into opposing cable retaining bodies at the part where the excess length of the optical fiber core is stored.
The cable can be replaced by replacing the hold-down body of the faulty cable with a hold-down body to which a new cable is attached.

As described above, with the connection box of the present invention, although additional work is required to repair and dismantle the insulating layer, it is possible to assemble or dismantle the box onboard the ship without having to perform work to tie up exterior wires, etc., which requires time. Become.

FIG. 4 is an enlarged cross-sectional structural diagram showing an embodiment of the present invention regarding a repair portion of an insulating sleeve layer, and is a 32
is a dummy insulation sleeve, 33 is an insulation auxiliary ring,
Numeral 34 is a nut for fixing the sheathing wire stop, and numeral 35 is a heat insulating material, and the other parts are the same as those in FIG. 2. Since it is necessary to fix the exterior wire retainer 10 to the pressure-resistant end plate 9 in an insulated state, the insulating end plate 18 has a U-shaped portion as shown in FIG.

On the other hand, since the insulating sleeve 19 must pass through the outer wire stopper 10 during assembly or disassembly,
Its inner diameter must be set larger than the outer diameter of the sheath wire stopper 10, and a step as shown in the fourth figure is created between the insulators 18 and 19 to be fused. When molding insulators together in areas with such steps,
The heat of the attached molding device die 41 must be sufficiently transmitted to the lower layer insulating sleeve 18 to raise the temperature to a melting point at which welding is possible, and the molding device must have a very large heat capacity. Furthermore, if all the stepped portions were to be filled with mold, the volume of the mold would be large and repair time would be required.

Therefore, as shown in FIG. 4, the insulation auxiliary ring 33 is attached to the stepped portion and heat-sealed to the lower insulation sleeve layer 18 by welding or molding. This is done by molding on the top surface of the ring. By this method, the fusion point is 36,
Although there is a disadvantage that there are only two locations shown at 37, there is no large step at the final fusion location 37, and
Therefore, there are advantages in that the heat capacity required for fusion can be reduced and temperature control can be facilitated, and that the mold volume can also be reduced, so that working time can also be reduced.

In addition, in order to prevent the heat of the mold 41 of the molding device from escaping to the metal outer wire stopper 34 and 10 side, a dummy sleeve 32 made of a plastic material with low thermal conductivity, and if necessary, a heat insulating material 3 are installed.
5 is preferably attached to the upper part of the exterior wire holding body 10 and molding is performed. Also, from the same meaning,
Considering that the spacer 21 can be easily disassembled during repair, it is preferable to use a plastic material that is difficult to thermally bond to the adhesive (such as nylon when polyethylene is used as the adhesive).

Although the present invention has been explained above using the cable having the structure shown in FIG. 2 as an example, the cable structure is not limited to that shown in FIG. 2, and is shown in FIG. 5 A or B. The present invention can be similarly applied to various cables that have one or more metal voltage-resistant layers 5 in the cable, and are constructed by surrounding the metal voltage-resistant layer 5 with an insulating jacket 7 and further with an armored wire 8. Needless to say.

In addition, although the connection box of the present invention has been explained above using the connection section between cables as an example, the connection box of the present invention is not limited to this example, and can be similarly applied to the connection section between cables and repeaters. Applicable to For example, as shown in FIG. 6, a repeater unit 38 and a shock absorbing buffer 39 are housed inside the pressure tubes 11 and 13, and at both ends, a tail fiber core 40 on the repeater side and a cable side are connected. Fiber core wire 3
By connecting these, a connection section between the cable and the repeater is constructed. It goes without saying that the various advantages of the present invention described in FIG. 3 can also be utilized in this example.

As described above in accordance with the various embodiments, according to the present invention, by fixing the connection box and covering the outer periphery of the movable pressure tube with a sleeve-shaped plastic insulating layer that is easy to disassemble, the inside of the cable can be fixed. It has the advantage that the metal voltage-resistant layer can be insulated from seawater, making it possible to secure communication or power supply lines using the metal voltage-resistant layer. At the same time, according to the present invention, it is possible to insulate the armored wire and its retaining body from the connection box body, which has the advantage of simultaneously blocking corrosion current through the armored wire, which was a problem with the conventional structure. It also has In addition, although the insulating sleeve layer must be dismantled and repaired when connecting onboard for repairs, the pressure-resistant tube is constructed so that it can be divided.
It is clear that the use of the above-mentioned insulating sleeve does not reduce the convenience of reconnecting the optical fiber core or relining the cable without dismantling the retaining parts of other tensile strength members such as the outer wire. .

Therefore, by using the connection box of the present invention for connecting submarine optical fiber cables, transmission is superior in various aspects such as ease of connection on board, corrosion resistance, securing of various electrical communication lines, and watertight reliability. It becomes possible to construct roads.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an example of a conventional submarine optical fiber cable connection box, Fig. 2 is a sectional view showing an example of a submarine optical fiber cable, and Fig. 3 is an example of the submarine optical fiber cable connection box of the present invention. 4 is an enlarged sectional view of the vicinity of the insulating layer repair portion in FIG. 3, FIG. 5 A and B are sectional views showing two examples of submarine optical fiber cables applicable to the present invention, and FIG. 1 is a sectional view showing an embodiment in which the present invention is applied to a connection between a submarine cable and a repeater. DESCRIPTION OF SYMBOLS 1... Submarine optical fiber cable, 2... Center support, 3... Optical fiber core wire, 4... Cushioning material, 5
...Metal voltage-resistant layer, 6... Internal tensile strength wire, 7... Insulating jacket, 8... Exterior wire, 9... Voltage-resistant end plate, 10
... Exterior wire holding body, 11 ... Fixed pressure tube, 1
2...Boots, 13...Movable pressure tube, 14...O
Ring, 15... Settling, 16, 17...
Joint nut, 18...Insulating end plate, 19...
...Insulating sleeve, 20, 22...Insulating layer joint part,
21...Spacer, 23...Protective tensile strength tube, 2
4...Insulation ring, 25...Tightening nut, 2
6... Plastic resin material, 27... Center steel wire retainer, 28, 29... Lead wire, 30... Waterproof bulkhead, 31... Watertight seal, 32... Dummy insulation sleeve, 33... Insulation auxiliary ring, 34...
Exterior wire holding body fixing nut, 35...Insulation material,
36, 37...Insulating sleeve fused portion, 38...Relay unit, 39...Relay buffer, 40...
Tail fiber core wire of repeater, 41...mold device mold.

Claims (1)

[Claims] 1. Interconnecting armored submarine optical fiber cables that have armored wires wound around the outer circumference of the cable and metal pressure-resistant layers placed inside the insulated cable jacket, or connecting the armored submarine optical fiber cables and repeaters. In the connection box, a pressure-resistant end plate fixed to the metal pressure-resistant layer while maintaining watertightness, a fixed pressure-resistant pipe fixed to the pressure-resistant end plate, and a movable pressure-resistant pipe capable of sliding on the outer peripheral surface of the fixed pressure-resistant pipe. Inside the connection box body, which is limited by an insulated end plate is attached to both sides of the pressure-resistant end plate and is bonded to the insulated cable jacket; An armored wire stopper having a through hole for the armored submarine optical fiber cable is installed to cover the insulated end face, and an insulating sleeve is fitted to the outer peripheral surface of the armored wire stopper and the movable pressure tube. , the insulating sleeve and the insulating end plate are connected at both ends of the insulating sleeve, and an insulator is inserted between the insulating sleeve and the outer wire stopper at both ends of the insulating sleeve, and the insulating sleeve is protected by a nut. A tensile strength tube is connected, the protective tensile strength tube is attached to cover the outer peripheral surface of the insulating sleeve, and is formed of a hard rubber material so as to cover the armored submarine optical fiber cable and the armored wire near the armored wire stop. A connection box for an armored submarine optical fiber cable, characterized in that the boot is connected to the protective tensile tube or the armored cable stop, and a flexible plastic resin material is injected into the inside of the boot.