JPH11164459A - Opgw gripping clamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent corrosion of an optical fiber compound overhead earth- wire, increasing loss of the optical fiber, or wire breakage in the clamp for the optical fiber compound overhead earth-wire, by providing a rubber for covering the optical fiber compound overhead earth-wire in the clamp for gripping the optical fiber compound overhead earth-wire. SOLUTION: Two optical fiber compound overhead earth-wires (OPGW) are clamped at an OPGW gripping clamp through a rubber 1, and fastened and gripped with a bolt passing in a bolt fitting hole. The rubber 1 is formed into such a shape as a cylinder is half-split so as to envelope the OPGW. A plurality of pole-shaped rubbers 3 are formed at the inner surface of the rubber 1, or at the side which comes into contact with the AS-wire of the OPGW. The rubber 1 is formed by conducting raising like lawn grass in its clamp inner periphery surface. The pole-shaped rubber 3 and the rubber 1 bury a long clearance generated between the stranding line of the AS-wire 5 and the clamp. The two OPGWs constituted of the AS-strand 5 and an OP-unit 4 are clamped and gripped concurrently.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp for OPGW used when pulling down an OPGW from a tower top to a joint box or a terminal box.

[0002]

2. Description of the Related Art OPGW (Composite Fiber-Optic Grou)
(nd Wire, optical fiber composite overhead ground wire) is installed on the top of the tower, and serves to protect the power transmission line and the tower from disasters caused by lightning, while using the optical fiber in the OP unit installed inside the tower. It performs optical communication and remote control. Therefore, at some point, it is necessary to lower the OPGW from the tower top to the joint box or terminal box. At this time, an OPGW grip and a tower cleat are used.

[0003] Fig. 6 is an explanatory view showing the usage state of a conventional OPGW grip and a tower cleat. The tower member 11 and the OPGW gripping clamp 13 that grips the OPGW 12 are connected by a tower cleat 14. The tower member 11 and the tower cleat 14 and the OPGW 12 and the OPGW gripping clamp 13 are firmly fixed by bolts and nuts, respectively.

FIG. 7 is a sectional view of the clamping clamp 13 for OPGW shown in FIG. OPGW12 is OP unit 15
And AS strands 16, and two O
The PGW is held by the holding clamp (only the right side is shown in FIG. 7). The gripping force is obtained by the bolt 17. When fixing the clamp with bolts,
A flat washer and a spring washer are appropriately used, and the arm of the tower cleat 14 is inserted and tightened.

As described above, the OPGW is held at a required position.

[0006]

The conventional OPGW clamping clamp has the following problems.

In the contact portion between the AS strand 16 of the OPGW 12 and the OPGW gripping clamp, the gripping clamp is O
In order to wrap the PGW over substantially the entire surface in the circumferential direction, an elongated gap is formed between the eye of the AS strand 16 of the OPGW and the inner surface of the clamping clamp. Insulating water or rainwater containing salt and the like accumulates in the gap due to the capillary phenomenon, and the AS wire 16 of the OPGW is corroded in the holding clamp.

When the corrosion further proceeds, the OP unit 15 is eroded by the corrosion products and the OP unit 15
Of the optical fiber is weakened, and the OP unit 15 is crushed to break the optical fiber. Even if the OP unit 15 is not crushed, a crack is formed and various substances constituting the OPGW or the OP unit 15 may enter or enter if the insulator cleaning water or rainwater containing salt reaches the optical fiber. Light loss increases due to the effect of hydrogen slightly contained in the absorbed water. Further, when micro cracks remain on the surface of the optical fiber, there is a problem that the cracks grow rapidly when the invading moisture touches the micro cracks and the optical fiber is disconnected.

It is conceivable to apply grease or the like to the elongated gap formed between the eye of the AS wire 16 of the OPGW and the inner surface of the clamp for clamping and fix the gap by filling the gap. It takes a long time and is not practical.

[0010] It is therefore an object of the present invention to overcome the disadvantages of the prior art described above and to provide an OPGW holding clamp within an OPGW holding clamp.
It is an object of the present invention to provide an OPGW clamping clamp which does not cause corrosion of the optical fiber, increase in loss of the optical fiber, and disconnection.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides an OGW having a clamp inside an OPGW.
A rubber covering the PGW was provided.

The rubber used is a rubber that is erected in a lawn shape on the inner peripheral surface of the clamp.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a plan view (a) and a cross-sectional view (b) showing an embodiment of an OPGW gripping clamp according to the present invention.
It is. FIG. 1 shows one set of two clamping clamps, the other being identical. Two OPGW are rubber 1
, And is clamped by the OPGW holding clamp, and is tightened by passing a bolt through the bolt mounting hole 2. The rubber 1 has a shape in which a cylinder is divided in half so as to wrap the OPGW.

FIG. 2 is an enlarged explanatory view of the rubber 1 of FIG. A large number of columnar rubbers 3 are provided on the inner surface of the rubber 1, that is, on the side in contact with the AS line of the OPGW. Thus, the rubber 1 is erected on the inner peripheral surface of the clamp in a turf shape. The columnar rubber 3 and the rubber 1 fill an elongated gap formed between the eye of the AS wire 5 and the clamp.

FIG. 3 is a sectional view showing a state where the OPGW is gripped by the OPGW gripping clamp of FIG. AS strand 5
, And two OPGWs composed of the OP unit 4 are simultaneously clamped and gripped. The gripping force is obtained by the bolt 6. When fixing the clamp with bolts, nuts, flat washers, spring washers are used as appropriate,
The tower cleat arm is inserted and tightened,
The PGW is held at the required position. The gap formed between the AS wire 5 and the gripping clamp is completely filled with the columnar rubber 3 and the rubber 1, so that insulator cleaning water or rainwater containing corrosive salt does not accumulate in the clamp.

FIG. 4 is a plan view (a) and a cross-sectional view (b) showing another first embodiment of the clamp for holding OPGW of the present invention.
It is. The cross-sectional view is an AA cross-sectional view of FIG.
A groove 8 having a rectangular cross section is formed on the outer periphery of the rubber 1 around the OP unit 4, in other words, when the OPGW is gripped,
It is provided radially around the GW. The total number of grooves is eight. The groove prevents the conventional capillary phenomenon and improves the flow of water in the clamp, thereby preventing insulator cleaning water or rainwater containing salt that corrodes the OPGW from accumulating in the clamp. The cross-sectional shape of the groove 8 is not limited to a rectangle, but may be a triangular meter, a polygon, a semicircle, a circle, or the like.
Further, the number of grooves is not limited to eight. In that case, it can be appropriately determined in consideration of the ease of processing of the clamp, the cross-sectional area of the OPGW to be gripped, and the like.

FIG. 5 is a plan view (a) and a sectional view (b) showing another second embodiment of the OPGW clamping clamp according to the present invention.
It is. The cross-sectional view is a cross-sectional view taken along the line BB of FIG. A cap 7 that covers the rubber 1 from outside is provided. This prevents insulator cleaning water, rainwater, and the like flowing from outside the clamp from entering the clamp.

As described above, the OPGW is gripped at a required position, and the OPGW is held in the OPGW grip for a long time.
It is possible to provide an OPGW grip for clamp which does not cause GW corrosion, increase in loss of optical fiber and disconnection.

[0019]

According to the clamp for OPGW gripping of the present invention, since the rubber, cap and groove are provided in the clamp, there is provided an extremely excellent effect that the corrosion of the OPGW, the increase in loss of the optical fiber, and the disconnection do not occur in the clamp. Demonstrate.

[Brief description of the drawings]

FIG. 1 is a plan view (a) and a cross-sectional view (b) showing an embodiment of an OPGW holding clamp according to the present invention.

FIG. 2 is an enlarged explanatory view of rubber in FIG. 1;

3 is a cross-sectional view showing a state where the OPGW is gripped by the OPGW grip for clamping in FIG. 1;

FIG. 4 is a plan view (a) and a sectional view (b) showing another first embodiment of the clamp for holding OPGW of the present invention.

FIGS. 5A and 5B are a plan view and a cross-sectional view showing another second embodiment of the OPGW gripping clamp of the present invention.

FIG. 6 is an explanatory view of a usage state of a conventional OPGW holding clamp and a tower cleat.

7 is a cross-sectional view illustrating a state where the OPGW is gripped by the OPGW grip for clamping in FIG. 6;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 rubber 2 bolt mounting hole 3 columnar rubber 4, 15 OP unit 5, 16 AS wire 6, 17 bolt 7 cap 8 groove 11 steel tower member 12 OPGW 13 OPGW gripping clamp 14 tower cleat

Claims (2)

[Claims] 1. A clamp for holding an OPGW, wherein the clamp for holding the OPGW is provided with rubber covering the OPGW in the clamp. 2. The OPG according to claim 1, wherein the rubber is erected in a lawn shape on the inner peripheral surface of the clamp.
W gripping clamp.