JPH0782128B2 - Derivation structure of optical fiber in insulator with built-in optical fiber - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an optical fiber lead-out structure in an optical fiber built-in insulator in which an optical fiber for signal transmission is housed.

(Prior Art) An optical fiber built-in insulator in which a signal transmission optical fiber is housed in a through hole in the center of a porcelain insulator body has the advantage that signals on the power-supply side can be easily extracted to the ground side. Active development is underway.

By the way, in such an insulator with a built-in optical fiber, the technique of connecting the optical fiber pulled out from the end of the through hole to another device or the optical fiber cable is an important issue for practical use, and the end is attached to the base by a flange or the like. A fixed SP insulator has already been proposed as Japanese Patent Application No. 63-36143. However, if an insulator with a built-in optical fiber is used, such as a clevis insulator, which can be flexibly connected to each other by a movable type connecting metal fitting,
Since the optical fiber may be cut due to the bending of the insulator, it is not possible to adopt the same structure as the fixed type SP insulator, and therefore, the optical fiber lead-out structure in the optical fiber built-in insulator has been required.

(Problems to be Solved by the Invention) The present invention solves the conventional problems as described above, and even when the insulator with an optical fiber is a clevis insulator that can be connected flexibly between the insulators, rainwater intrusion and The present invention has been completed in order to provide an optical fiber lead-out structure in an optical fiber built-in insulator that allows the optical fiber to be drawn out without causing troubles such as cutting of the optical fiber.

(Means for Solving the Problem) The above-mentioned problem is that the clevis-type connecting metal fitting having a hollow inside is fixed airtightly to the end of the insulator main body in which the optical fiber is housed in the through hole, and the optical fiber is penetrated. While pulling out from the hole to this hollow chamber and connecting with a space, a flexible optical fiber cable is attached to the side wall perpendicular to the bending surface of the insulator body of the connecting metal fitting, and the tension member at the center of this optical fiber cable The optical fiber is characterized in that the optical fiber is led out to the outside through the optical fiber cable while the side wall of the connecting metal fitting is drawn and fixed in the hollow chamber through a fixing metal fitting having a tubular portion penetrating in a direction orthogonal to the side wall. This can be solved by the optical fiber lead-out structure in the built-in insulator.

Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

(Example) In FIG. 1, (1) is a porcelain insulator main body, (2) is a through hole formed in the center of the insulator main body (1), (3)
Is an optical fiber housed inside the through hole (2). A flange (4) is joined by cement (5) to the end portion of the insulator with a built-in optical fiber, and a movable type connecting metal fitting (the inside of which is a hollow chamber (6) using the flange (4) ( 7) is airtightly fixed with an O-ring (8) interposed. As the movable type connecting fitting (7), a clevis fitting which can connect the insulators to each other so as to be bendable in a specific direction is used. Then, a specific portion of the optical fiber (3) pulled out from the inside of the through hole (2) into the hollow chamber (6) of the connecting fitting (7) is in a state where a loop is formed as shown in the figure to allow a certain amount of space. At the inside of the hollow chamber (6), they are connected by fusion splicing or an optical connector.

A flexible optical fiber cable (9) is attached to the side wall of the connecting fitting (7). The optical fiber cable (9) of the present embodiment has an outer periphery covered with a bellows-shaped flexible stainless pipe (10), and an optical fiber (3) and a tension member (11) for enclosing and protecting the optical fiber (3) are provided inside. Along with housing, a grease-like material such as silicon grease is enclosed between the stainless pipe (10) and the optical fiber cable (9) to form an airtight structure. The tension member (11) of such an optical fiber cable (9) is hollow along with the optical fiber therein through a fixing metal fitting (12) having a tubular portion penetrating a side wall of the connecting metal fitting (7) in a direction orthogonal to the side wall. It is drawn into and fixed in the chamber (6). The optical fiber (3) passes through the inside of the optical fiber cable (9) and is led to the outside.
In addition, the optical fiber cable (9) and the fixing bracket (1
2) is attached to the side wall of the insulator perpendicular to the specific bending surface so that the insulator body (1) connected by the clevis-type connecting metal fitting (7) is not subjected to tensile compression even when bent. And

FIG. 2 shows a second embodiment, in which an optical fiber cable (9) using an aluminum pipe is used as the tension member (11). Also in this embodiment, the tension member (11) is fixed to the inside of the hollow chamber (6) by the fixing metal fitting (12) integrated with the tension member (11). The optical fiber (3) is led out to the outside through the inside of the tension member (11) made of this aluminum pipe.

In the third embodiment of FIG. 3, OPGW is used as the optical fiber cable (9). This is a structure in which a tension member (11) made of an aluminum pipe is provided in the center of an aluminum stranded wire (17), and an optical fiber (3) is passed through the tension member (11). Further, in this embodiment, the inside of the hollow chamber (6) of the connecting fitting (7) is filled with silicon grease or urethane foam to prevent intrusion of water and the like.

(Operation) According to the optical fiber lead-out structure of the present invention thus configured, the optical fiber (3) pulled out from the through hole (2) has a clearance inside the hollow chamber (6) of the coupling fitting (7). The tension member (11) of the flexible optical fiber cable (9), which is connected by holding, is attached to the side wall of the insulator of the connecting metal fitting (7) in a direction perpendicular to the specific bending surface of the insulator. Since it penetrates the side wall of 7) and is drawn into the hollow chamber (6) and is fixed by the fixing metal fitting (12), the insulator main bodies (1), (1) are bent at the connecting metal fitting (7). Even in such a case, the flexible optical fiber cable (9) only bends, and no tensile force acts on the optical fiber (3).
Therefore, the optical fiber built-in insulator having the optical fiber lead-out structure of the present invention does not have a risk of breaking the optical fiber (3) during use. Further, in the optical fiber lead-out structure of the present invention, the connection between the hollow chamber (6) and the optical fiber cable (9), the hollow chamber (6) and the insulator body (1).
Since the connection part with is airtight structure, there is no risk of rainwater entering and degrading the optical fiber (3).
It is possible to ensure long-term reliability of the insulator with a built-in optical fiber.

FIG. 4 shows two optical fiber built-in insulators (15) each having the above-mentioned optical fiber lead-out structure on one side.
1 shows a 275KV class optical fiber insulator device which is incorporated at both ends of a conventional flange-connected type optical fiber insulator (16). In the case of 154KV class, the central insulator (16) with built-in optical fiber may be eliminated and two sets may be formed. In the case of 77KV class, a single optical fiber having the above-mentioned optical fiber lead-out structure at both upper and lower ends. The built-in insulator (15) may be used.

However, in the case of 500KV class, five insulators with built-in optical fiber must be connected in series, and if the insulators of 275KV or less are all flange-connected, they can be broken without being able to withstand bending loads. There is a nature. Therefore, in such a case, the insulator (15) with a built-in optical fiber located in the middle is flexibly connected to each other via the connecting metal fittings, and both optical fibers (3) are connected via the flexible optical fiber cable (9). Just connect them.

As described above, in the optical fiber insulator device using the optical fiber lead-out structure of the present invention, since the optical fiber built-in insulators can be flexibly connected, bending stress can be avoided, and the optical fiber passing through each optical fiber built-in insulator ( Through 3), it is possible to easily and surely take out the signal on the charging side to the grounding side.

(Effects of the Invention) As described above, according to the optical fiber lead-out structure of the present invention, rainwater enters or the optical fiber is cut from the end of the clevis-type optical fiber built-in insulator that can flexibly connect the insulators to each other. The optical fiber can be pulled out without causing troubles such as. Therefore, the present invention has an extremely large contribution to industrial development as an optical fiber lead-out structure in an insulator with a built-in optical fiber that solves the conventional problems.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of an optical fiber lead-out structure in an optical fiber built-in insulator of the present invention, FIG. 2 is a sectional view showing a second embodiment, and FIG. 3 is a third embodiment. FIG. 4 is a front view showing an insulator device incorporating an optical fiber according to the present invention. (1): Insulator body, (2): Through hole, (3): Optical fiber, (6): Hollow chamber, (7): Connecting metal fitting, (9): Optical fiber cable, (11): Tension member,
(12): Fixing bracket, (15): Insulator with built-in optical fiber

Claims (1)

[Claims] 1. A clevis-type connecting metal fitting (7) having a hollow chamber (6) inside at the end of an insulator body (1) containing an optical fiber (3) inside a through hole (2) is airtight. Fix and connect the optical fiber (3) from the through hole (2) to the hollow chamber (6) with a clearance and connect it to the bending surface of the insulator body (1) of the connecting metal fitting (7). A flexible optical fiber cable (9) is attached to the vertical side wall, and this optical fiber cable (9) is attached.
Connect the tension member (11) at the center of the
The side wall of the optical fiber (3) is pulled into the hollow chamber (6) through a fixing member (12) having a tubular portion penetrating in a direction orthogonal to the side wall and fixed, while the optical fiber (3) is passed through this optical fiber cable (9) A structure for guiding out an optical fiber in an insulator with a built-in optical fiber, which is characterized in that