JP2780456B2 - Terminal section of optical / electric power composite cable - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a terminal portion of a novel optical / power composite cable, and particularly to a terminal of an optical / power composite cable capable of improving workability of handling an optical fiber. It is about the department.

[Prior Art] Generally, an optical / power composite cable is a composite of a power cable and an optical fiber by utilizing the non-inductive property of an optical fiber. This type of cable employs, for example, a configuration as shown in FIG.

The illustrated example shows a composite cable in which an optical fiber is composited with a submarine cable.
Is formed with a conductor 3 having an oil passage 2 therein.
An insulating layer 4, a lead coating 5 for preventing inundation, and a plastic anticorrosive layer 6 are formed on the outer peripheral portion of the conductor 3, and a large number of iron wires 7 sharing the tension during manufacturing and installation are formed outside the insulating layer 4.
Are provided, and cushion layers 8 are formed on the inner and outer sides of the iron wire 7, respectively.

An optical fiber cable 9 is provided between the lead coating 5 and the anticorrosion layer 6, and this optical fiber cable 9 has a metal pipe 11 having an outer diameter of 1.8 mm and a wall thickness of 0.2 mm as shown in FIG. The optical fiber 12 is housed inside. Optical fiber 12
Since is protected by the metal pipe 11, it can withstand external pressure, for example, can withstand a water pressure of 1000 kg / cm ² . Further, by using stainless steel for the metal pipe 11, excellent corrosion resistance and high long-term reliability are obtained.

In this way, the submarine composite cable 1 in which the power cable and the optical fiber are composited is economical because it is not necessary to newly lay a signal line, and only lay it once. for that reason,
Investigations on this type of composite cable are being advanced in various fields.

In the composite cable 1, it is necessary to inspect the transmission characteristics of the optical fiber 12, such as after manufacturing, after transport, and before connecting the cable. For that purpose, it is necessary to easily take out the optical fiber 12 from the terminal portion of the composite cable 1.

FIG. 6 shows a terminal portion of the composite cable 1.

A terminal portion of the conductor 3 is inserted into and held in the sleeve 13, and a skirt member 14 is provided on an outer peripheral portion of the sleeve 13, and a terminal portion of the iron wire 7 is welded to an outer peripheral portion of the skirt member 14. It is connected. The sleeve 13 and the skirt member 14 are screwed together and integrally connected. When tension is applied to the hook 15 connected to the rear end of the sleeve 13, the conductor 3 and the iron wire 7 share the tension. Extend equally and do not cause relative displacement.

On the other hand, the terminal portion of the optical fiber cable 9 is inserted through the skirt member 14, and the extra length 9a pulled out behind the skirt member 14 is drawn into the terminal box 16 and accommodated therein. 12 are connected to each other. Since the terminal box 16 may rotate at the time of rewinding the composite cable 1 or the like,
It is integrally fixed to the iron wire 7 and the like.

 Reference numeral 17 denotes a lead-welded portion, and reference numeral 18 denotes a stopper.

[Problems to be Solved by the Invention] By the way, since the weight of the composite cable 1 reaches 50 kg / m, the tension reaches several tons in the drum winding work of the cable 1 or the like. For this reason, it is necessary to take measures such as covering the optical fiber cable 9 which is pulled out in the rear direction of the skirt member 14 and exposed to the outside with a protective tube. In addition, since the cable 1 is passed through a guide roll or the like during the same operation, it is necessary to remove the terminal box 16 at that time, which makes the operation extremely complicated and unfavorable in terms of safety.

In addition, in the "power and optical communication composite cable terminal structure" of Japanese Utility Model Application Laid-Open No. 60-94606, the configuration merely accommodates the extra length of the optical communication cable in the cap,
When a tensile force is applied to the optical communication cable, the cable terminal may be pulled in.

Similarly, Japanese Patent Laid-Open Publication No. Sho 61-44603 discloses an "extremely long optical fiber holder" for an optical fiber cable which merely accommodates the extra length of an optical fiber cable.

The present invention has been made to effectively solve the above problems.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a terminal section of an optical / power composite cable capable of improving workability such as an optical fiber connection operation at the terminal section of the composite cable.

[Means for Solving the Problems] The present invention relates to a light source having a sleeve for gripping a conductor terminal of a power cable, and a skirt member provided so as to be surrounded by an outer peripheral portion of the sleeve and through which a terminal of an optical fiber is inserted. At the terminal portion of the power / power composite cable, a cover member for accommodating an extra length of the optical fiber drawn rearward is detachably attached to the skirt member,
A guide portion is provided in the cover member for guiding the extra length portion in a circumferential direction so as to be folded and bent, and the guide portion is turned over the extra length portion of the optical fiber cable pulled out behind the skirt member, In order to generate a frictional force that prevents the extra length from being pulled in and to bend at an angle that does not degrade the transmission characteristics of the optical fiber,
A bent portion having a radius of curvature of mm to 50 mm is formed,
The extra length portion bent by the guide portion is wound concentrically with the power cable in the cover member.

[Operation] As described above, since the cover member for accommodating the excess length of the optical fiber cable is detachably attached to the skirt member, workability such as an optical fiber connection operation is improved. Further, the extra length of the optical fiber cable is folded back and guided by a guide member having a bent portion having a predetermined radius of curvature, and is wound concentrically with the power cable in the skirt member. It is possible to securely fix the optical fiber cable and prevent the extra length of the optical fiber cable from being pulled in when a tensile force is applied to the composite cable when the composite cable is laid.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show a composite cable in which an optical fiber is combined with a submarine cable. The composite cable 1 has a conductor 3 having an oil passage 2 therein. On the outer periphery of the conductor 3, an insulating layer 4, a lead coating 5 for preventing inundation, and a corrosion-resistant layer 6 made of plastic are formed, and outside the conductor 3, a number of iron wires 7 for sharing tension during manufacturing and installation are provided. Cushion layers 8 are formed on the inner and outer sides of the iron wires 7, respectively.

An optical fiber cable 9 is provided between the lead sheath 5 and the anticorrosion layer 6. As shown in FIG. 3, the optical fiber cable is placed inside a stainless steel metal pipe 11.
12 is inserted.

As shown in FIG. 1, the terminal of the conductor 3 is inserted and held in a sleeve 21 having a hook 15 at one end, and is screwed to the outer periphery of the sleeve 21 so as to surround it. A skirt member 22 is provided integrally with the skirt member 22. The end of the iron wire 7 is welded and connected to the outer periphery of the skirt member 22, and an insertion hole 23 through which the optical fiber cable 9 is inserted is formed. I have. Reference numeral 17 denotes a lead-welded portion, and reference numeral 18 denotes a stopper.

In particular, the skirt member 22 has a cover member 24 for accommodating the extra length 9a of the optical fiber cable 9 pulled out behind the skirt member 22.
Is detachably attached by screwing or the like. That is, as shown in FIG. 2 and FIG.
22 has a step 25 whose rear end is reduced in diameter and opened rearward.
A reduced diameter portion 26 fitted to the outer peripheral portion of the sleeve 21 is formed to form a cover member 24 having the same outer diameter as the skirt member 22 so as to cover the step 25 formed by the reduced diameter portion 26. Is attached. Therefore, the cover member
24 has a ring-shaped accommodation room 27 for accommodating the extra length 9a.
Is formed.

An arc-shaped guide portion 28 for guiding the extra length portion 9a to be folded and bent in the circumferential direction is formed in the accommodation room 27 at a position close to the insertion hole 23, and the guide portion 28 is formed by the skirt member 22. Are arranged at equal intervals along the circumferential direction on the step portion 25. In this embodiment, since the four-core optical fiber cable 9 is pulled out, four guide portions 28 are formed.

As shown in FIG. 3, a bent portion 28a having a predetermined radius of curvature is formed at the distal end of the guide portion 28 facing the insertion hole 23 to guide the bending of the extra length portion 9a. This radius of curvature is set in the range of 30 mm to 50 mm.

The extra length 9a bent at the predetermined curvature by the guide portion 28 and guided in the circumferential direction in the cover member 24 in this manner is wound around the cover member 24 concentrically with the power cable, as shown in the illustrated example. The extra long portions 9a are wound around the outer circumference of the reduced diameter portion 26 in the skirt member 22 so as to be sequentially and alternately arranged in the axial direction. The winding diameter at this time is 80 to 100 mm, and the excess length of 80 to 100 cm can be absorbed by about three windings. When it is necessary to connect the optical fibers 12 in order to measure the transmission characteristics of the optical fibers, as shown in FIG. 3, the optical fibers 12 are exposed to a predetermined length from the metal pipe 11, and the optical fibers 12 are connected to each other. This is stacked and accommodated on the extra-long metal pipe 11 via a cushion layer (not shown). Thus, the optical fiber
By accommodating 12 in a stacked manner, the accommodation width of the cover member 24 can be set short. The width of the accommodation room 27 at this time is 10
It is about 0 mm.

Therefore, the terminal portion of the optical fiber cable 9 is fixed by its concentric portion 9a being wound concentrically with the power cable in the cover member 24, and when the optical fiber is connected by removing the cover member 24, etc. Extra length part wound and accommodated
9a can be opened to the outside.

As described above, according to the present invention, since the cover member 24 for accommodating the extra length portion 9a of the optical fiber cable 9 is detachably attached to the skirt member 22, only by removing the cover member 24, the remaining space wound inside the skirt member 22 is accommodated. The long portion 9a can be opened to the outside, and the conventional protective tube and terminal box 16 are not required, so that workability can be improved.

The extra length 9a of the optical fiber cable 9 is a cover member.
Since the composite cable 1 is wound and accommodated in the composite cable 1, the extra length 9a does not shift when tension is applied to the composite cable 1 due to the frictional force or the tightening force. Therefore, the power transmission characteristics of the optical fiber 11 do not deteriorate.

The radius of curvature of the bent portion 28a of the guide portion 28 is 30 mm to 50 m.
Since the length is set in the range of m, when the composite cable 1 is stretched by pulling during laying manufacturing, the extra length portion 9a is not pulled in. 30mm to 50mm setting range is extra length 9a
In addition to generating a frictional force for preventing the pull-in of the optical fiber 12, the extra-length portion 9a is bent at an optimum angle without deteriorating the transmission characteristics of the optical fiber 12.

Experiments have confirmed that when the radius of curvature is set to 50 mm, the extra length 9a is not pulled in even when the composite cable 1 extends 0.5%.

[Effects of the Invention] In summary, according to the present invention, the following excellent effects are exhibited.

(1) Since the cover member for accommodating the extra length of the optical fiber cable is detachably attached to the skirt member, workability such as cable replacement and optical fiber connection can be improved.

(2) Since the extra length of the optical fiber is bent along the guide portion and wound and accommodated in the cover member concentrically with the power cable, the extra length is surely formed by the frictional force or the tightening force. It can be fixed, and it is possible to prevent the extra length portion from being displaced or pulled in when tension is applied to the composite cable.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a composite cable of the present invention, FIG. 2 is a perspective view showing a main part of the composite cable, FIG. 3 is an enlarged view showing a main part of FIG. 2, and FIG. FIG. 5 is a sectional view showing a composite cable, FIG. 5 is a sectional view showing an optical fiber cable, and FIG. 6 is a side sectional view of a conventional composite cable. In the figure, 1 is a composite cable, 3 is a conductor, 9 is an optical fiber cable, 9a is an extra length, 21 is a sleeve, 22 is a skirt member, 24 is a cover member, 28 is a guide portion, and 28a is a bent portion. .

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 62-188708 (JP, U) Japanese Utility Model Sho 61-44603 (JP, U) Japanese Utility Model Sho 63-70510 (JP, U) (58) Survey Field (Int.Cl. ⁶ , DB name) G02B 6/24

Claims (1)

(57) [Claims] An end of an optical / power composite cable having a sleeve for gripping a conductor end of a power cable and a skirt member provided so as to surround an outer peripheral portion of the sleeve and through which an end of an optical fiber cable is inserted. A cover member for accommodating a surplus portion of the optical fiber cable drawn rearward thereof is detachably attached to the skirt member, and the surplus portion is folded and bent in the circumferential direction in the cover member. A guide portion for guiding is provided, the guide portion folds an excess length portion of the optical fiber cable pulled out behind the skirt member, generates a frictional force for preventing the extra length portion from being pulled in, and generates light. In order to bend at an angle that does not reduce the transmission characteristics of the fiber, a bent portion having a radius of curvature of 30 mm to 50 mm is formed, A terminal portion of the combined optical / power cable, wherein the extra length bent by the guide portion is wound concentrically with the power cable in a cover member.