JP2771380B2 - Non-ceramic insulator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-ceramic insulator having a sheath made of an elastic insulating material, and more particularly to a long-stem non-ceramic insulator incorporating an optical fiber.

[0002]

2. Description of the Related Art Conventionally, an insulator incorporating an optical fiber for transmitting an optical signal has been proposed. First, as disclosed in Japanese Patent Application Laid-Open Nos. 60-15402 and 60-22580, a through hole is formed in the center of a porcelain insulator and an optical fiber is passed through the hole. .
As an example of a non-ceramic insulator instead of a porcelain insulator, there is one proposed by the present inventors in JP-A-63-46405. In the non-ceramic insulator, an optical fiber is spirally wound around the core of the FRP, the optical fiber is embedded in the inside by an adhesive layer, and a jacket made of rubber or synthetic resin is molded around the outer periphery. Since the optical fiber buried in the non-ceramic insulator is protected by the adhesive layer, the optical fiber is not cut when molding with rubber or synthetic resin as a jacket, so that transmission of an optical signal is not hindered.

[0003]

However, the above non-ceramic insulators or porcelain insulators are not usually made exclusively for optical fibers and also serve other functions. Uses a FRP core. Therefore, it becomes heavy and it is inconvenient to carry without bending. In addition, there is also a problem that a product after molding requires space in production and it is difficult to produce a long product.

In recent years, the use of an optical fiber built-in insulator has been increasing for transmission lines in mountainous areas. However, long insulators cannot be transported by obstacles such as forests, and there is a demand for insulators that can be bent. Are also coming out.

SUMMARY OF THE INVENTION An object of the present invention is to provide a non-ceramic insulator which is bendable and lightweight and is dedicated to optical fibers.

[0006]

In order to achieve the above object, according to a first aspect of the present invention, a core, a metal gripping metal provided at an end of the core, and an outer peripheral surface of the core are provided. A sheath made of an elastic insulating material having a plurality of caps formed on the outside, and the core is a reinforcing material in which fibers are knitted or woven in a hollow cylindrical shape, and a cylindrical shape accommodated inside the reinforcing material. An elastic material core, and a metal core housed inside a reinforcing material at both ends of the elastic material core so as to correspond to the grip metal,
The gist is that the reinforcing member is made of an optical fiber spirally wound and fixed on the outer periphery of the reinforcing member.

In the second invention, the gist is that the gripping metal is fixed to the metal core by pressure bonding via a reinforcing material.

[0008]

According to the above construction, the elastic material core mainly constituting the core has elasticity and is freely bendable. At this time, tension due to bending is generated in the reinforcing material constituting the core, but the tension does not work directly in the axial direction of the optical fiber spirally wound around the reinforcing material, and the optical fiber is cut and damaged. There is no fear.

On the other hand, a metal core is inserted into the end of the reinforcing material,
When the grip metal is crimped, the metal core is a solid cylinder and hardly deforms, and the reinforcing material is sandwiched between the grip metal and
The connection is secure and the strength required after installation is sufficiently satisfied.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIGS. 1 and 2,
The non-ceramic insulator is mainly composed of a core 1, a jacket 3 made of an elastic insulating material having a plurality of caps 2 described later on the outside, and holding brackets 4 and 4 a. Bush-shaped optical connectors 5 and 5a for connecting optical fibers are provided at both ends of the insulator, and a drawing optical fiber cable 6 is wired outside.

An outer cover 3 made of an elastic insulating material such as silicon rubber or ethylene propylene rubber covers the entire surface of the core 1 seamlessly and has excellent air resistance and tracking resistance. A cap 2 is formed on the outer cover 3 to secure a surface leakage distance. The end of the jacket 3 is accommodated between the metal sleeves 12, 12a of the gripping metal fittings 4, 4a and the core 1, and is fixed firmly and tightly by pressing the metal sleeves 12, 12a in the radial direction. Have been.

[0012] The core 1 is made of polyamide fiber.
As shown in FIG. 3, a reinforcing member 7 woven into a hollow cylindrical shape and a rubber core 8 as a columnar elastic material are housed therein. The rubber core 8 is provided to prevent the reinforcing member 7 from being crushed by the molding pressure during the rubber molding of the jacket 3. A caulking metal core 9 made of aluminum is similarly accommodated at both ends inside the reinforcing member 7, and optical connectors 5 and 5 a are fitted to the outer periphery thereof. The optical fiber 10 is spirally wound around the reinforcing member 7 and coated with an elastic rubber-based adhesive for protecting the optical fiber.

The spiral pitch of the optical fiber 10 is as follows:
It is appropriately determined in consideration of the allowable curvature of the optical fiber 10, the thermal expansion and contraction of the reinforcing member 7 and the displacement under mechanical stress, and the economic efficiency.

At both ends of the core 1, a gripping metal 4 made of a metal such as aluminum alloy, steel, or ductile cast iron,
4a is provided by pressing the metal core 9 with the reinforcing material 7 interposed therebetween. The grip 4 has a structure, for example, a ring or a clevis-like mounting portion 11 that is directly or indirectly mounted on a support such as an electric wire or a tower arm. A metal sleeve 12 for accommodating and joining the end of the jacket 3 is integrally provided on the end portion 13 side of the core 1 of the mounting portion 11.

The manufacturing method and operation of the above configuration will be described. The aluminum metal core 9 is inserted into the end of the cylindrical reinforcing member 7, and the inserted portion is inserted into the end 13a of the grip 4a. Then, the gripping metal 4a
The outer periphery of the end 13a is crimped. Since the aluminum metal core 9 is a solid columnar shape, it hardly deforms.
Is fixed by caulking with the gripping metal 4a. Next, the cylindrical rubber core 8 is inserted into the reinforcing member 7 and the optical connectors 5 and 5 are inserted.
a is fitted to the reinforcing member 7. The other metal core 9 is accommodated in the reinforcing member 7 and similarly caulked and fixed to the gripping member 4.
An optical fiber 10 is spirally wound around the reinforcing member 7 in advance, and is adhesively fixed with a rubber-based adhesive, and its end is connected to the optical connectors 5 and 5a. Finally, a rubber mold is applied around the periphery and the process is completed. In this mold, the jacket 3 is molded by a length corresponding to a predetermined number of caps 2, and the molding is continuously performed a plurality of times. At that time, the portion protruding outward from the mold can be bent. Therefore, the mold may be small and the space around the mold may be small.

The optical signal modulated on the basis of the voltage or current of the transmission line is transmitted from the optical connector 5a to the optical connector 5 at the other end again via the optical fiber 10 wound around the outer periphery of the reinforcing member 7.
Transmitted to This signal is transmitted to a detector installed in a substation or the like via an optical fiber provided on an overhead ground wire.

At the leading end of the optical fiber 10 from the non-ceramic insulator of the above embodiment, optical fiber optical connectors 5, 5a are provided. For this reason, the connection of the external optical fiber cable 6 only needs to be fitted to the optical connectors 5 and 5a, and erection or replacement with a steel tower can be easily performed. Further, since the rubber core 8 has a specific gravity of 1.3 to 1.4 as compared with the specific gravity 2.2 of the conventional FRP rod, the weight can be reduced. In addition, the rubber core 8 is elastic and can flex freely. Although the reinforcing member 7 expands and contracts due to the stress caused by this bending, there is no fear of cutting because the optical fiber 10 is spirally wound around the reinforcing member 7.

As described above, since the insulator of this embodiment is flexible, it is convenient to store it in a narrow place or the like, and it is easy to avoid obstacles during transportation. It should be noted that the present invention is not limited to the above embodiment, and can be modified and configured as follows without departing from the spirit of the invention.

(1) In the above embodiment, as shown in FIG. 3, the cylindrical reinforcing member 7 is formed by spirally knitting a polyamide fiber to form a tube. However, as in the reinforcing member 14 shown in FIG. Fifteen
May be aligned in the axial direction, and the weft 16 may be aligned in the circumferential direction. According to this configuration, even if a tension is applied to the reinforcing member 14, the elongation is small. Therefore, it is possible to further prevent an excessive load from being applied to the optical fiber 10 wound around the reinforcing member 14.

(2) Fibers other than polyamide fibers are used as the reinforcing material 7. (3) The reinforcing member 7 is constituted by knitting of fibers. (4) Instead of the rubber core 8 as the elastic material, the core may be made of plastic having elasticity.

[0021]

According to the present invention, since the core is made of high-strength fiber and elastic rubber, it can be bent freely and a long non-ceramic insulator can be stored in a relatively narrow space. In addition, since the optical fiber is easy to carry and is limited to the function of an optical fiber, the diameter can be reduced and the weight can be significantly reduced.

In addition, since it can be bent similarly, there is an effect that a large space is not required in manufacturing. On the other hand, since the metal core is used only at the end of the reinforcing member, an effect is obtained that the gripping metal can be securely fixed and the tensile strength can be maintained.

[Brief description of the drawings]

FIG. 1 is a front view of a non-ceramic insulator according to one embodiment of the present invention.

FIG. 2 is a sectional view of a main part showing an end of the non-ceramic insulator.

FIG. 3 is a plan view showing the cylindrical reinforcing member.

FIG. 4 is a plan view showing another example of the cylindrical reinforcing member.

[Explanation of symbols]

1 core, 2 shades, 3 jackets, 4 and 4a grips, 7
Reinforcing material, 8 rubber core, 9 metal core, 10 optical fiber.

Claims (2)

(57) [Claims] 1. A core made of a metal, a metal gripping metal disposed at an end of the core, and an elastic insulating material that covers an outer peripheral surface of the core and has a plurality of caps formed outside. Wherein the core comprises a reinforcing material in which fibers are knitted or woven in a hollow cylindrical shape, a cylindrical elastic material core housed inside the reinforcing material, and the gripping member at both ends of the elastic material core. A non-ceramic insulator comprising: a metal core accommodated in a reinforcing member corresponding to a metal fitting; and an optical fiber spirally wound around the reinforcing member. 2. The non-ceramic insulator according to claim 1, wherein the gripping metal is fixed to a metal core by pressure bonding via a reinforcing material.