JPS61217006A - Optical fiber core terminal part - Google Patents

Abstract

PURPOSE:To prevent the breakage of an optical fiber core by inserting a connector communicated and bored with an optical fiber insertion hole and optical fiber core insertion hole at the axial center onto an optical fiber core terminal part where an optical fiber is exposed and adhering the same by the adhesive agent having prescribed characteristics. CONSTITUTION:The optical fiber core 1 is constituted by forming a silicone resin layer on the optical fiber 2 and forming a coating 2A consisting of a resin curable by UV, etc. thereon. The coating 2A is removed by a prescribed length in the terminal part of the optical fiber core 1 and the fiber 2 is exposed by the prescribed length. The optical fiber insertion hole 4 and the optical fiber core insertion hole 5 are communicated at the axial center by the connector 3. The connector 3 is inserted onto the terminal part of the core 1 in such a manner that the top end of the fiber 2 is positioned on the plane at the top end thereof and is thoroughly adhered to the optical fiber core terminal part by the adhesive agent 6 having >=5% breaking extension in particular, by which the adhesive agent 6 is built up from the end at the base part of the connector 3 to the surface of the core 1.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an end portion of an optical fiber.

(Conventional wave? lf) In recent years, optical fiber core wires have been developed in which a silicone resin layer is formed on an optical fiber and an ultraviolet curing resin coating is applied thereon.

In the case of connecting such optical 7-aiper cables to each other, conventionally, as shown in FIG. A connector bulb is provided on the top of the connector bulb, in which the optical fiber insertion hole 13 and the optical fiber insertion hole 14 are connected to each other at the axis thereof, and the tip of the optical fiber U is placed on the tip plane of the connector bulb. The elongation at break of the above-mentioned optical fiber core wire and connector is inserted so that they are in the same position, and the elongation at break is li! , less than 5% adhesive 15
In order to completely bond the optical fiber 10 from the base end of the connector bulb and to prevent the optical fiber 10 from breaking from the base end due to bending stress concentrated at the base end of the connector bulb, The above adhesive 15
As shown in the figure, the ends of the optical fibers 11 and 11 located on the tip plane of the connector bar 12 were brought into close contact to connect the optical fiber cores. .

(Problems with the Prior Art) In the above-mentioned conventional optical fiber coated wire end portion, when a slight bending stress is applied to the optical fiber coated wire 10, the optical fiber coated wire 10 is stacked from the base end of the connectorle to the optical fiber coated wire 1o. There was a problem in that the optical fiber core wire 1° was easily broken along with the adhesive 15 from the adhesive portion, making it impossible to transmit optical signals.

(Means for solving the problem) In order to solve the above problem, the present inventors have developed a core diameter of 50 μm.
On the optical fiber with m1 cladding diameter of 125 μm, outer diameter α3
A silicone resin layer with fllφ and a Young's modulus of 1ookg/- is applied, and on top of that a silicone resin layer with an outer diameter of α9111φ and a Young's modulus of 1o o
A tensile test was conducted by applying a conventionally used adhesive to a thickness of 10 μm on the UV-curing resin coating of an optical fiber core with a J9/-1 elongation rate of 40%. The elongation at break of the agent was measured. As a result, the elongation rate at break is! It is less than 5% and is extremely brittle, and due to this, the optical fiber core wire 1o is broken together with the adhesive from the adhesive portion that is piled up over the optical fiber core wire 10 from the base end of the connector bulb due to a slight bending stress. I found out. The present invention is based on the above-mentioned research results, and the present invention provides an optical fiber insertion hole and an optical fiber insertion hole at the axial center on the optical fiber end portion in which the optical fiber at the axial center is exposed by removing a predetermined length of the coating from the end. Inserting a connector with communicating insertion holes, and completely bonding the inserted optical fiber core wire and the connector with an adhesive having a breaking elongation of 5% or more,
The conventional problems are solved by applying the above-mentioned adhesive from the base end of the connector to the optical fiber core to form an optical fiber core end portion.

(Embodiments of the present invention) Hereinafter, embodiments of the present invention will be described with reference to the drawings. In FIG. A coating such as an ultraviolet curing resin coating is applied thereon. At the end of the optical fiber core wire 1, two coatings are removed for a predetermined length, and the optical fiber 2 is exposed for a predetermined length. Reference numeral 3 denotes a connector in which an optical 7 eyeper insertion hole 4 and an optical fiber core insertion hole 5 are provided in communication with each other on the axis, and the connector 3 has the tip of the optical fiber 2 on its tip plane as shown in the figure. The optical fiber 7 is inserted onto the end of the optical fiber core 1 so that The adhesive 6 is applied over the optical fiber core 1 from the end.

Next, for the optical fiber 7-IPA fiber terminal part of the present invention and the conventional optical fiber fiber terminal part described above, a part of the connector constituting the terminal part is fixed, and the optical 7-IPA fiber core is tilted downward at a 90° angle.
A breaking test was conducted by bending.

The results were as shown in the table below.

As is clear from the table above, in the conventional optical fiber end using adhesive, the entire optical fiber was broken from one end of the connector along with the adhesive, whereas the optical fiber of the present invention There was no floor at the end of the 7 AIPA core wire.

(Effects of the Invention) The present invention is as described above, and an optical fiber insertion hole 4 is formed at the axial center on the end portion of the optical fiber core 1 in which the optical fiber 2 at the axial center is exposed for a predetermined length from the end. and optical fiber core insertion hole 5
Insert the connector 3 which has a hole for communicating with the connector 3, and completely adhere the inserted optical fiber core wire 7 and the connector through the adhesive 6 having a breaking elongation rate of 5% or more, and from the base end of the connector 3. The adhesive 6 is applied over the optical fiber core 1.
By arranging the optical fiber to form the optical fiber end portion, even if bending stress is applied to the optical fiber core 1, the optical fiber core does not break from the base end of the connector as in the conventional case. It has the great advantage of not being

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view showing a conventional optical fiber end portion. 1: Optical fiber core wire 2: Optical fiber zA: Covered 1 [
3: Y nectar 4: Optical fiber insertion hole 5: Optical fiber insertion hole 6: Adhesive No. 1
rod 2 bacteria

Claims (1)

[Claims] A predetermined length of the coating was removed from the terminal to expose the optical fiber at the axial center, and an optical fiber insertion hole and an optical fiber insertion hole were bored at the axial center so as to communicate with each other. A connector is fitted and inserted, and the fitted optical fiber core wire and the connector are bonded together with an adhesive having a breaking elongation of 5% or more, and the adhesive is applied from the base end of the connector to the optical fiber core wire. An optical fiber core terminal part characterized by being made of