JP2803516B2 - Optical fiber composite overhead ground wire connection fitting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection structure for connecting optical fiber composite overhead ground wires (OPGW) to each other via a connection box mounted on a steel tower, and more particularly to a connection box and a connection box connected thereto. The present invention relates to a structure in which the sealing property of a sheath layer of an optical fiber composite overhead ground wire is improved.

[0002]

2. Description of the Related Art As shown in FIG. 5, an optical fiber composite overhead ground wire 1 has an integrated function by combining an optical fiber communication line and an overhead ground wire of a transmission line. Optical fiber unit 3 with fiber 2 as one unit
And an envelope AS wire layer 4 covering the same. The envelope AS wire layer 4 is composed of an aluminum pipe 5 and an aluminum sheathed wire (AS wire) 6 twisted around the outer periphery thereof. ing. The aluminum pipe 5 accommodates the optical fiber unit 3 therein and mechanically protects the same.
The aluminum-coated steel wire 6 is formed by pulling out the inside of a die while extruding aluminum around the steel wire. The steel wire and the aluminum are completely integrated by friction welding, so that the tension of the steel wire and It has heat resistance, electrical conductivity and corrosion resistance of aluminum, and has excellent properties as an overhead ground wire. On the other hand, the optical fiber 2 combined with the overhead ground wire
Can cope with a demand for a transmission circuit for a large amount of signals, such as operation management of a transmission system due to an increasing power demand, and an electromagnetic induction failure due to an ultra-high voltage. Therefore, the optical fiber composite overhead ground wire 1 combining the advantages of the optical fiber unit 3 and the aluminum steel wire 6 is widely used as a communication line because of its high reliability after installation.

As shown in FIG. 6, an optical fiber composite overhead ground wire 1 is provided inside a connection box 7 provided on a power transmission tower.
The connection is made with a sufficient extra length 8 so that the expansion at the time of high temperature or strong wind does not impose a load on the optical fiber 2. As described above, in order to pull in and connect only the optical fiber 2 in the connection box 7, it is necessary to support or engage the jacket AS wire layer 4 with the connection box 7, and generally, the connection fitting 9 as shown in FIG.
Is used.

FIG. 7 shows a connection fitting 9 for an optical fiber composite overhead ground wire 1 which has been conventionally employed. The connection fitting 9 is attached to the connection box 7 while holding the optical fiber composite overhead ground wire 1. It is provided in the entrance 10. More specifically, the connection fitting 9 strips the outer AS line layer 4 from the step, guides the optical fiber unit 3 having a predetermined length exposed into the connection box 7, and forms the outer AS line layer serving as the outer shell. 4 and is connected to the connection box 7. The connection fitting 9 has a plug member 11 formed at the end thereof so as to be inserted and fitted into the inlet 10 of the connection box 7 and is formed integrally with the plug member 11, and is provided with the outer AS line layer. 4 is provided with a gripping member 12 formed to wrap and grip a part of the outer peripheral portion and a flange member 13 for fixing to the connection box 7.
In addition, the holding member 12 is superimposed on this,
A clamp member 17 is provided for clamping the optical fiber composite overhead ground wire 1 over the exposed portion of the jacket AS wire layer 4 wrapped in the gripping member 12. The plug member 11 is provided with an insertion hole 14 formed to penetrate the axis thereof, and the insertion hole 14 is configured so that the optical fiber unit 3 is inserted with the aluminum pipe 5 covered. . The jacket AS wire layer 4 wrapped in the gripping member 12 is configured such that the clamp member 17 is overlapped and clamped. Thus, the optical fiber composite overhead ground wire 1
Is gripped by the connection fitting 9, the plug member 11 is inserted and fitted into the inlet 10 of the connection box 7, and the flange member 13 integrally formed with the plug member 11 is fixed to the connection box 7 with screws 25. By doing so, they will be linked. The connection box 7 and the flange member 13 are sealed with an O-ring or the like (not shown) so that rainwater does not enter the connection box 7. In addition, the optical fiber unit 3 inserted into the connection box 7 is peeled off the aluminum pipe 5 as a coating layer, and is connected for each element wire.

[0005]

By the way, in the structure of the conventional connection fitting, as shown in FIG.
Of the optical fiber composite overhead ground wire 1 is formed integrally with the plug member 11.
The clamp member 17 has a groove for grasping a part of the outer periphery of the wire layer 4, and the clamp member 17 is superimposed on the exposed portion of the jacket AS wire layer 4 held in the groove. However, there is a problem that a predetermined gap is formed at the joint between the clamp member 17 and the gripping member 12. In particular, the outer diameter of the optical fiber composite overhead ground wire 1 is not always uniform, and a gap tends to occur even when the clamp member 17 is fastened to the gripping member 12 with the fastening bolt 21. The present inventor has found that the following problem occurs when a slight gap is formed between the holding member 12 of the connection fitting 9 and the clamp member 17 as described above.

[0006] When rainwater enters the inside from such a gap, it is difficult for the water to be drained and tends to be retained as it is for a long time. In particular, inside the gripping member 12, the cut surface when the aluminum steel wire (AS wire) is peeled is exposed as it is, and when rainwater stays on the cut surface of the aluminum and steel wire, these cuts are made. Corrosion due to the contact potential difference between the members easily occurs. Further, when these corrosion products contact the aluminum pipe 5 and the metal contact portion of the aluminum-coated steel wire and stay, the corrosion products are liable to be corroded due to the potential difference cell action or the like, or the density of these corrosion products is increased. Is high, so that corrosion can easily develop along the direction of gravity. If such corrosion occurs for a long time, a hole is formed in the aluminum pipe 5 covering the optical fiber unit 3 or the aluminum pipe 5 is deformed due to reduced strength, and the optical fiber unit 3 accommodated in the inside is deformed.
May be damaged. In this case, although the optical fiber composite overhead ground wire 1 has many advantages as described above, the possibility of affecting the reliability as a communication line increases. In particular, sea salt particles fly in the coastal area, but the effect on the corrosion is very large, and even a very small amount of sea salt greatly promotes the corrosion. Therefore, these measures have been strongly desired.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a connector for an optical fiber composite overhead ground wire which effectively solves the conventional problem of corrosion at a connection portion, has excellent durability, and maintains communication reliability. .

[0008]

In order to achieve the above object, the present invention provides an optical fiber unit in which a sheath AS wire layer of an optical fiber composite overhead ground wire terminal is stripped and a predetermined length of the optical fiber unit is exposed. A plug member to be inserted into an optical fiber unit inlet provided in the connection box, in a connection fitting for connecting and supporting the optical fiber composite overhead ground wire to the connection box when guided into the connection box attached to the electric wire tower. An insertion hole that penetrates through the plug member to guide the optical fiber unit into the connection box, and wraps a part of an outer peripheral portion of the jacket AS wire layer formed integrally with the plug member. A gripping member to be gripped, a clamp member for clamping the optical fiber composite overhead ground wire which is superimposed on the gripping member so as to cover the exposed portion of the jacket AS wire layer wrapped therein, Is obtained by constituting the fitting for an optical fiber composite overhead ground wire is provided and a seal member that is interposed between the junction of the clamp member and the gripping member.

Further, the gripping member and the clamp member are formed to extend downward in the direction of gravity with respect to the connection box, and the optical fiber composite overhead ground wire gripped and clamped at the lower ends thereof. A cover member extending from the outer peripheral portion by a predetermined length and surrounding with a predetermined gap is provided to constitute a connection fitting for an optical fiber composite overhead ground wire.

[0010]

With the above construction, the seal member is interposed between the joint between the holding member for holding the outer AS wire layer and the clamp member, thereby preventing rainwater from entering the joint from the inside. And internal corrosion can be prevented.

The above-mentioned clamp member, which extends downward by a predetermined length in the direction of gravity, and a cover member formed at the lower end of the gripping member are connected to the rainwater which is dripped or flows down from the jacket layer of the connection fitting. Draining can be performed without flowing down the fiber composite overhead ground wire.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

As shown in FIGS. 1 and 2, the optical fiber composite overhead ground wire 1 has, as described above, an optical fiber unit 3 having a plurality of optical fibers 2 as one unit and an outermost shell covering the optical fiber unit 3. The AS-line layer 4 is composed of an aluminum pipe 5 and an aluminum-coated steel wire (AS line) 6. The connection fitting 9 has a plug member 11 inserted and fitted into a lead-in opening 10 of the connection box 7 at the tip thereof, and is formed integrally with the plug member 11 to hold the outer AS line layer 4. Member 1
2 is provided. The plug member 11 and the grip member 1
2, a flange member 13 is formed extending in the radial direction, abutting on the outer peripheral edge of the inlet port 10 so as to be in contact therewith and connected and fixed to the connection box 7. Plug member 11
Is formed with an insertion hole 14 through which the optical fiber unit 3 covered with the aluminum pipe 5 is inserted. An optical fiber unit supporting portion 15 having an insertion hole 14 for inserting the optical fiber unit 3 through a predetermined length is provided on a gripping member 12 formed integrally with the plug member 11. An accommodation groove 16 for fitting and holding a substantially half outer periphery of the outer layer 4 is formed. The accommodation groove 16 is configured to have a semi-cylindrical shape. Further, a clamping member 17 which is opposed to the holding groove portion 16 of the gripping member 12 and which covers and covers the exposed AS line layer 4 which is left wrapped in the holding groove portion 16 and is overlapped therewith is overlapped. The clamp member 17 has a semi-cylindrical shape. That is, as shown in the figure,
The accommodating groove 16 for gripping the outer AS line layer 4 is formed in a substantially semi-cylindrical shape, and the clamp member 17 is formed in a substantially semi-cylindrical shape. And a cylindrical body surrounding the optical fiber composite overhead ground wire 1 having a substantially circular cross section. In addition, insertion holes 22 for inserting the tightening bolts 21 are formed on both sides of the clamp member 17, and the seal member 23 is formed in a semi-cylindrical shape as shown in FIG. It is configured to have a substantially horseshoe shape having a half ring portion so as to be continuously overlapped along the joint surface of the clamp member 17. Further, this sealing member 23 is formed integrally with the joining surface of the clamping member 17 by being overlapped therewith.
The hole 22A for inserting this is formed.

In particular, the sealing member 23 is
If they are integrally attached in advance, the seal member 23 is attached between the clamp member 17 and the grip member 12 simply by attaching the clamp member 17 to the grip member 12, thereby facilitating the work.

Next, the operation of this embodiment will be described.

As shown in FIGS. 1 and 2, an optical fiber composite overhead ground wire 1 is connected to a connection box 7 mounted on a power transmission tower.
When connecting the plug member 11, the plug member 11
The optical fiber unit 3 covered with the aluminum pipe 5 is inserted through the insertion hole 14 into the
After the jacket AS wire layer 4 is gripped in the accommodation groove 16 of the above, the clamp member 17 is overlapped on the exposed portion of the gripped jacket AS wire layer 4 so as to cover the exposed portion, and the fastening bolt 21 is used. The clamp member 17 and the gripping member 12 are connected to each other. As described above, the grip member 12 and the clamp member 17 are fastened by the fastening bolts 21 with the outer AS wire layer 4 interposed therebetween, so that the seal member 23 is provided on the joint surface between the grip member 12 and the clamp member 17. Since it is interposed, the jacket AS wire layer 4 to be clamped is completely sealed. Accordingly, it is possible to prevent rainwater or the like from entering the inside from the joint surface between the gripping member 12 and the clamp member 17. As described above, since the cut end surface of the jacketed AS wire layer 4 to be clamped can be sealed from rainwater or the like, corrosion can be prevented from occurring and reliability as a communication line can be improved as much as possible. it can. After the outer AS line layer 4 is thus clamped by the gripping member 12 and the clamp member 17, the plug member 1
While inserting the optical fiber unit 3 drawn out from 1 through the predetermined length into the connection box 7 by leading it from the inlet 10,
The plug member 11 is fitted, the flange member 13 is fixed to the connection box 7 via the screw 25, and a seal member such as an O-ring is interposed between the flange member 13 and the connection box 7. . Thus, the optical fiber composite overhead ground wire 1 is fixed to the connection box 7.

When the seal member 23 is tightened to the elastic limit, the quality deteriorates due to excessive tightening due to thermal expansion of the member in summer. In consideration of such weather resistance, the material of the seal member 23 is preferably ethylene, propylene, rubber, silicon rubber, neoprene rubber, or the like. Further, in consideration of the above conditions, it was confirmed in a specific experimental example that the deformation rate of the attachment of the seal member 23 is optimally about 10 to 30%. For example, according to the result of a rainfall test on silicon rubber, when the deformation rate of the silicon rubber in the connection fitting 9 was 20%, there was no infiltration of rainwater and an extremely good waterproof effect was obtained.

Next, another embodiment of the present invention will be described with reference to FIG.

In this embodiment, the shape of the joint between the clamp member 17 and the holding member 12 in the above embodiment is improved. That is, in the embodiment shown in FIGS. 1 and 2, when the clamp member 17 and the gripping member 12 are joined, the intersection angle between the axial portion 19 and the radial portion 18 is formed at 90 degrees. On the other hand, in this embodiment, as shown in the figure, the axial portion 19 and the radial portion 18 are formed such that their intersection angle is set to 90 degrees or more. That is, as shown in FIG. 3, the radial portion 18 is formed so as to be joined to the axial portion 19 at a gentle angle with respect to the axial portion 19, and more specifically, the intersection angle between the axial direction and the radial direction is 90 degrees or more. It is formed so as to have a predetermined radius of curvature at the intersection and to be rounded. As in the previous embodiment, a seal member 23 is interposed between the joints between the clamp member 17 and the holding member 12.

With the above arrangement, when the joint between the clamp member 17 and the gripping member 12 is provided with a gradient from the radial portion 18 to the axial portion 19, the seal member 23 sandwiched by the joint deforms. The amount can be made uniform over the whole, and the influence of the displacement of the clamp member 17 can be minimized. In other words, when the displacement of the clamp member 17 occurs, the sealing member 23 that is unevenly spread is crushed near the intersection of the radial portion 18 and the axial portion 19 to cause wrinkles or sharp edges. There is a possibility that the seal member 23 may be damaged or the seal member 23 cannot be deformed uniformly, and this has been effectively solved. By configuring as in the present embodiment, the intersection is obtuse, so that the seal member 23 slides on it, and is not squeezed and forcibly crushed to avoid wrinkles, and can be prevented from being damaged. .

Further, another embodiment will be described with reference to FIG.

In any of the above embodiments, the connection fitting 9 is inserted and connected to the connection box 7 mounted on the steel tower from below in the direction of gravity or vertically upward from below. That is, as shown in FIGS. 2 and 3, an inlet 10 is opened below or at the bottom of the connection box 7 so as to face downward in the direction of gravity, and the optical fiber composite overhead is connected to the inlet 10 through the connection fitting 9. The ground wire 1 will be inserted.

In the embodiment shown in FIG. 4, the gripping member 12 and the clamp member 17 are formed so as to extend downward in the direction of gravity or in the vertical direction with respect to the connection box 7 as in the above-described embodiment. Particularly, in this embodiment, the lower end of the gripping member 12 and the clamp member 17 is extended by a predetermined length to the outer peripheral portion of the optical fiber composite overhead wire 1 to be gripped and clamped, and The cover member 24 surrounding the gap S is integrally formed. As shown in the figure, the cover member 24 is formed to have a substantially skirt shape, so that drainage of rainwater or the like flowing down along the outer peripheral portions of the gripping member 12 and the clamp member 17 is improved, and at the same time, rainwater or the like is removed. Blowing can be prevented.

As described above, the holding member 1 is
The drainage of the rainwater flowing down the outer periphery of the clamp 2 and the clamp member 17 can be improved, and the blowing of the rainwater can be prevented, so that the internal corrosion of the connection fitting 9 can be prevented.

In any of the above embodiments, anticorrosive grease such as silicone grease having excellent water repellency is applied in advance to the housing groove 16 of the gripping member 12 and the inner surface of the clamp member 17 constituting the connection fitting 9. If the jacket A
The S-line layer 4 and its cut portions are clamped and coated with anticorrosive grease. In this way, by covering the outer cover AS wire layer 4 and its cut portion with the anticorrosive grease, the corrosion resistance of the optical fiber composite overhead ground wire 1 clamped by the connection fitting 9 is improved as much as possible. Will be.

[0026]

As is apparent from the above description, the present invention exerts the following excellent effects.

(1) Corrosion can be prevented beforehand by preventing rainwater and sea salt particles from entering the inside of the connection fitting, and the durability of the optical fiber composite overhead ground wire is improved. The reliability of communication can be greatly improved.

(2) The structure is simple and versatile.

[Brief description of the drawings]

FIG. 1 is a partially exploded perspective view showing an embodiment of the present invention.

FIG. 2 is a side view showing an embodiment of the present invention.

FIG. 3 is a side view showing an embodiment of the present invention.

FIG. 4 is a partially broken side view showing the embodiment of the present invention.

FIG. 5 is a cross-sectional view of an optical fiber composite overhead ground wire.

FIG. 6 is a side view showing a conventional example.

FIG. 7 is an enlarged side view of a main part showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical fiber composite overhead ground wire 3 Optical fiber unit 4 Jacket AS wire layer 7 Connection box 9 Connection fitting 10 Inlet 11 Plug member 12 Holding member 17 Clamp member 23 Seal member 24 Cover member

Continuation of the front page (56) References JP-A 62-161202 (JP, U) JP-A 62-197103 (JP, U) JP-A 1-71704 (JP, U) (58) Fields surveyed (Int .Cl. ⁶ , DB name) G02B 6/46 G02B 6/24 H02G 15/02 H02G 7/02

Claims (2)

(57) [Claims] 1. A sheath A of an optical fiber composite overhead ground wire terminal portion
A connection fitting for connecting and supporting the optical fiber composite overhead ground wire to the connection box when the optical fiber unit having the S-line layer stripped off and exposed to a predetermined length is guided into a connection box mounted on a power transmission tower. In the above, a plug member is inserted into the optical fiber unit inlet provided in the connection box, the connection fitting, an insertion hole for penetrating the plug member and guiding the optical fiber unit into the connection box, A gripping member formed integrally with the plug member and wrapping and gripping a part of the outer peripheral portion of the jacket AS line layer; and on the gripping member, on an exposed portion of the jacket AS line layer wrapped therein. It is characterized by comprising a clamp member for clamping the optical fiber composite overhead ground wire which is superimposed to cover this, and a seal member interposed between a joint portion between the clamp member and the gripping member. Fiber composite overhead ground wire for connection fittings. 2. The optical fiber composite overhead ground wire, wherein the gripping member and the clamp member are formed to extend downward in the direction of gravity with respect to the connection box, and are gripped and clamped at their lower ends. The connecting member for an optical fiber composite overhead ground wire according to claim 1, wherein a cover member is provided on an outer peripheral portion of the cover member, the cover member extending a predetermined length and surrounding the predetermined distance.