JPH02250007A - Mutli-stage stacked glasses incorporated with optical fiber - Google Patents

Abstract

PURPOSE:To prevent a glass main body from breaking owing to the thermal expansion of a sealing material, to prevent a ground-fault accident from occurring owing to a leak current, and to maintain joining strength for a long period by sealing end surfaces of both glass main bodies to be joined with an adhesive material and forming a gap between the adhesive material and sealing material. CONSTITUTION:The end surfaces of both the glasses 1 are sealed with resin 5 as the adhesive material. Further, the gap S formed between the resin 5 and silicone rubber 4 absorbs the expanding silicone rubber 4 when the silicone rubber 4 expands thermally. Consequently, rain water is prevented from passing between the end surfaces and reaching a through hole 2 from outside, so a leak current is prevented from flowing to cause a ground fault. Further, the joining strength between both the glass main bodies 1 is maintained for a long period.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an insulator with built-in multi-tiered optical fibers.

[Prior Art] Traditionally, insulators with built-in optical fibers have been manufactured by inserting an optical fiber into a through hole formed in the insulator body, and using a sealing material such as silicone rubber to fill the inside of the through hole with the optical fiber. It is well known that it is fixed. A multi-tiered optical fiber built-in insulator made by bonding a plurality of insulator bodies of such optical fiber built-in insulators to each other includes an insulator in which a bendable connecting fitting is attached between the end faces of the same insulator bodies that are bonded to each other, It is known that the end surfaces of the main body are directly joined so as to be in close contact with each other, and the outer surface of the joined end is tightened and fixed with a connecting fitting.

[Problems to be Solved by the Invention] However, in the conventional multi-stacked optical fiber built-in insulator, there is a problem in the inside of the through hole between the end face of the insulator body and the connecting fitting, or between the joint end faces of the insulator body that are directly joined. There are problems in that the filled sealing material deteriorates due to moisture seeping in from the cement, and that the sealing material thermally expands in the narrow gap where it seeps when the temperature rises, damaging the insulator body.

In addition, the insulator body is usually sealed near the outer surface of the joint end and cemented from the outside.
If the sealing in this part breaks and rainwater or the like infiltrates between the end faces of both insulators and enters the through hole, leakage current will flow and there is a risk that a ground fault will occur.

Furthermore, it is not possible to maintain the bonded state between the end faces of the insulator body over a long period of time simply by tightening and fixing with conventional connecting fittings, etc., and there is a problem that the bonding strength of the insulator body deteriorates over time. Ta.

The present invention has been made to solve the above-mentioned problems of the prior art, and its purpose is to prevent the sealing material from seeping between the end faces of the insulator body, and to prevent the sealing material from seeping between the end faces of the insulator body. In addition to preventing damage to the insulator body caused by thermal expansion of the sealing material in the insulator body, it also prevents rainwater, etc. from entering between the end faces of the insulator body from the outside and causing leakage current to flow into the through hole, causing a ground fault. It is an object of the present invention to provide an insulator with a built-in multi-tiered optical fiber that can prevent the above problems and maintain the bonding strength between the end faces of the insulator body for a long period of time.

[Means for Solving the Problem 1] In order to achieve the above-mentioned object, the present invention joins together a plurality of insulator bodies in which through-holes for inserting optical fibers are formed, and one side of the insulator bodies to be joined. The space between them is sealed with an adhesive material.

Note that the adhesive material may be a resin adhesive, or an inorganic material may be heat-treated for sealing.

The adhesive material seals between the end face of the insulator body and a spacer interposed between the end faces, and the spacer is made of a material having substantially the same coefficient of thermal expansion as the insulator body, and the spacer is made of a material having substantially the same coefficient of thermal expansion as the insulator body. At least a through hole having a diameter larger than that of the through hole may be formed at a position corresponding to the through hole of the main body.

Then, the optical fiber is sealed with a sealing material, and a gap is provided between the adhesive material and the sealing material.

Furthermore, the shape of the joint end face of the insulator body, which has a through hole for inserting an optical fiber and is joined in multiple stages, may be made larger in diameter than the cross-sectional shape of the body of the insulator body.

[Operation] Apply adhesive material to the end faces of the insulator bodies to be joined,
When both end faces are pressed and bonded, the end faces of the insulator body are sealed by the adhesive material, and no narrow gap is created, so the sealing material filled in the through hole does not seep between the end faces.

Similarly, by sealing the end faces of the insulator body, rainwater or the like is prevented from entering from the outside through the end faces and reaching the through hole.

Furthermore, when the adhesive material that seals the end faces is cured, the bonding strength of the insulator body is maintained for a long period of time by the adhesive material.

In addition, the voids absorb thermal expansion of the sealing material.

Furthermore, if the shape of the joint end face of the insulator body is made larger in diameter than the cross-sectional shape of the body of the insulator body, the bonding area between the end faces becomes wider and the joint strength is further improved.

[Example] Next, an example embodying the present invention will be described with reference to the drawings.

1 and 2 show a first embodiment of the present invention, in which 1 is an insulator as an insulator body, and two upper and lower insulators 1 are connected in series with both end surfaces joined to each other. has been done. 2 is a through hole formed in the center of the insulator 1;
3 is an optical fiber passing through the through hole 2, and 4 is silicone rubber filled in the through hole 2. This silicone rubber 4 is for preventing rainwater etc. from entering into the through hole 2 and leakage current from flowing.

As shown in FIG. 2, the end faces of the two insulators 1 to be joined are sealed with resin 5 as an adhesive material. In addition, in the same figure, 6 is a connecting fitting for reinforcing the joint strength between the ends of both insulators 1 by resin 5, and 7 is for joining the connecting fitting 6 and the outer surface of the end of both insulators 1. cement.

Moreover, S is a void formed between the resin 5 and the silicone rubber 4. This gap S is formed when the silicone rubber 4 expands due to heat.
It is designed to absorb.

Next, the operation of the multi-tiered optical fiber built-in insulator constructed as described above will be explained.

When resin 5 is applied to the end surfaces of the insulators 1 connected vertically to be joined to each other, and both end surfaces are pressed and bonded, the end surfaces of both insulators 1 are bonded together.

Then, the end faces of both insulators 1 are sealed in a watertight manner, so no narrow gap occurs between the same end faces, and therefore, the silicone rubber 4 filled in the through hole 2 does not stain between the end faces of both insulators 1. prevented from exiting.

Similarly, even if rainwater etc. infiltrates from the cement 7,
Since the end faces of both insulators 1 are sealed watertight, rainwater, etc. is prevented from passing between the end faces and penetrating into the through hole 2.

Furthermore, the two insulators 1 whose end portions are bonded to each other are firmly fixed by the resin 5 that seals the end surfaces.

FIG. 3 shows a second embodiment of the present invention, in which the same members as in the first embodiment are given the same reference numerals. In the figure, 8 is a glaze as an adhesive material, which seals the ends of the two insulators 1 to be joined.

In this second embodiment, glaze 8 is applied to the end faces, and the end faces are pressed and bonded together temporarily.

Then, by heat-treating both insulators 1 in this state, the glaze 8 between the end faces is sintered, and the ends of both insulators 1 are firmly fixed.

In addition to the glaze 8, it is also possible to use an inorganic material such as inorganic glass as the adhesive material to be sintered by heat treatment.

Next, FIG. 4 shows a third embodiment of the present invention, in which the same members as in the first and second embodiments are designated by the same reference numerals. In the figure, reference numeral 9 denotes a Kovar plate as a spacer, which is made of a material having approximately the same coefficient of thermal expansion as the insulator 1, and has a through hole 10 in its center with a diameter half that of the insulator 1.
is formed. Note that 11 is inorganic glass as an adhesive material for sealing between the end face of the insulator 1 and the surface of the Kovar plate 9.

In this third embodiment, similarly to the second embodiment, inorganic glass 11 is applied to the end face of the insulator 1 and the surface of the Kovar plate 9, and the inorganic glass 11 is sintered by heat treatment while temporarily bonded by pressure bonding. The end faces of both insulators 1 and the surface of the Kovar plate 9 are firmly fixed together.

In addition, in this third embodiment, the Kovar plate 9 is the insulator 1.
Since it is made of a material with the same coefficient of thermal expansion as the insulator 1, the sintering work can be reduced by applying inorganic glass 11 to the end face of the insulator 1 and the surface of the Kovar plate 9 before sintering, press bonding, and heat treating. It will only take a few times.

In addition, by connecting an electrode to the Kovar plate 9 and applying a voltage to the electrode, the Kovar plate 9 is made to generate heat, and the inorganic glass coated between the ends of both the insulators 1 and near the periphery of the through hole 2 is heated. It is also possible to melt and adhere.

Next, FIG. 5 shows a fourth embodiment of the present invention, and the shapes of the joint ends of both insulators 1 in the first embodiment, which are joined to each other, are as shown in FIG. The diameter is larger than that of the cross-sectional shape. Therefore, the connecting ring 6, which is tightened and fixed to the outer surface of the joint end, also has a shape that matches the outer shape of the joint end.

In this fourth embodiment, the end faces of both insulators 1 that are joined to each other are joined over a wider area than the conventional small-diameter insulators, so that the joining strength of both end faces that are joined to each other is further improved. In addition, in this fourth embodiment, the diameter of the joined end surfaces of both insulators 1 in the first embodiment is increased, but the diameter can be similarly increased in the second and third embodiments.

In this embodiment, one optical fiber 3 is inserted into the through hole 2, but it is also possible to insert a plurality of optical fibers as necessary.

It is also possible to fill the voids S with a foamable organic material.

It should be noted that the present invention is not limited to the above-described embodiments, and may be modified as desired without departing from the spirit of the present invention.

[Effects] As explained above, the present invention has the following unique effects.

By sealing the end faces of both insulator bodies with the adhesive material, rainwater, etc. from the outside is prevented from passing between the end faces and infiltrating into the through hole, thereby preventing leakage current from flowing and causing a ground fault. be able to.

In addition, if a resin adhesive material is used as the adhesive material, it is possible to easily bond the two insulator bodies together, but if an inorganic material is used and sealed by heat treatment, the inorganic material will sinter, so it will last for a long time. The bonding strength between the end faces of both insulator bodies can be more strongly maintained over a period of time.

Furthermore, a spacer made of a material with almost the same coefficient of thermal expansion as the insulator body is interposed between the end faces of both insulator bodies, an inorganic material is applied between the spacer and the end face of the insulator body, and an electrode is placed on the spacer. By connecting these and applying a voltage, the inorganic material is reliably sintered between the end faces up to the vicinity of the through hole, thereby further improving the bonding strength between the end faces.

Further, even if the sealing material filled in the through hole seeps out between the end faces of the insulator due to thermal expansion, it is absorbed by the gap, thereby preventing damage to the insulator body.

Furthermore, since the shape of the joint end face of the insulator body is made larger in diameter than the cross-sectional shape of the body of the insulator body, the area to be bonded becomes larger and the joint strength can be further improved.

[Brief explanation of drawings]

FIG. 1 is an overall front sectional view of the first embodiment of the present invention, FIG. 2 is an enlarged sectional view of the main part, FIG. 3 is an enlarged sectional view of the main part of the second embodiment, and FIG. 4 is the third embodiment. An enlarged sectional view of the main parts of the example,
FIG. 5 is an enlarged sectional view of the main part of the fourth embodiment. An insulator 1 as an insulator body, a through hole 2, an optical fiber 3, and a resin 5 as an adhesive material. Same glaze 8°, same inorganic glass 11, Kovar plate 9 as a spacer, through hole 10,
Air gap S0 Patent applicant Nippon Insulator Co., Ltd. Representative Patent attorney On 1) Hironobu (1 idiot)

Claims (1)

[Claims] 1. A plurality of insulator bodies in which through-holes for optical fiber insertion are formed are bonded to each other, and the end surfaces of the two insulator bodies to be bonded are sealed with an adhesive material. Multi-layered optical fiber built-in insulator. 2. The multi-tiered optical fiber built-in insulator according to claim 1, wherein the adhesive material is a resin adhesive. 3. The multi-tiered optical fiber built-in insulator according to claim 1, wherein the adhesive material is an inorganic material and is sealed by heat treatment. 4. The adhesive material is for sealing between the end faces of both the insulator bodies and a spacer interposed between the end faces, and the spacer is made of a material having substantially the same coefficient of thermal expansion as the insulator body. 4. The multi-tiered optical fiber built-in insulator according to claim 1, wherein a through hole having a diameter larger than at least the through hole is formed at a position corresponding to the through hole of the insulator body. 5. The multi-tiered optical fiber built-in insulator according to claim 1, wherein the optical fiber is sealed with a sealing material, and a gap is provided between the adhesive material and the sealing material. 6. Claims 1 to 4 characterized in that the shape of the joined end face of the insulator body, which is formed with a through hole for the insertion of an optical fiber and is joined in multiple stages, is larger in diameter than the cross-sectional shape of the body of the insulator body.
The described insulator with built-in multi-tiered optical fibers.