JPH06201926A - Bundled fiber base attachment structure - Google Patents

Abstract

(57) [Summary] [Purpose] To make it easy to insert a bundle fiber, to prevent scratches from attaching to the bundle fiber, and to reduce the size of the base. [Structure] An end portion 2 of a bundle fiber 1 in which a large number of optical fibers are converged is connected to two or more cylindrical bases 3 whose inner diameters are uniform in the axial direction and whose inner diameters are different from each other Inserted so that it would be on the side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base attachment structure for a bundle fiber in which a large number of optical fibers are converged.

[0002]

2. Description of the Related Art As shown in FIG. 3, a bundle fiber 11 is often used as a light guide 13 by covering the outer periphery thereof with a flexible tube 12. For example, as shown in FIG. 2, when the components of the IC 21, which is one of the electronic components, are bonded to each other with an ultraviolet curing resin, an ultraviolet light source (UV light source) 2
2, one end of the light guide 13 is connected, the ultraviolet light from the light source 22 is transmitted by the light guide 13, and the ultraviolet light is emitted from the other end of the light guide 13 to the ultraviolet curable resin applied to the IC 21. It is used to irradiate and cure the resin. By the way, this irradiation method has the advantages that no heat is generated, it can be cured quickly, spot curing is possible, and the irradiation position of light can be freely moved. In addition to this, the light guide 13 is used in various fields including a gastroscope.

As shown in FIG. 2, since the light guide 13 is used by being connected to various devices, normally, as shown in FIG. 3, a cap (inner cap) is provided at both longitudinal ends (incident end and exit end) of the bundle fiber 11. ) 14 is attached, and an outer cap 15 is provided at the end of the flexible pipe 12 and outside the inner cap 14.
Is installed.

It is desirable that the inner cap 14 and the outer cap 15 are downsized in order to downsize other devices. For that purpose, it is necessary to increase the filling rate of the bundle fiber 11 into the inner base 14. Therefore, conventionally, as shown in FIG. 4, the outer diameter B of the bundle fiber 11 and the inner diameter A of the inner base 14 are set.
Had tight tolerances. However, if the tolerance is tight, it becomes difficult to insert the bundle fiber 11 into the inner base 14,
The fiber 11 sometimes breaks, which is a drawback.

In order to solve the above-mentioned drawbacks, in recent years, as shown in FIG. 5, a tapered base 14 having a tapered inner diameter.
Is used.

[0006]

When the tapered die 14 is used, there are the following problems. ． If the taper is steep, it becomes difficult to insert the bundle fiber 11. In addition, the bundle fiber 11
Since it is inserted into the base 14 with the silicon coating of each converged optical fiber peeled off, the optical fiber may be damaged. ． In order to solve the above-mentioned problem, the length of the die 14 may be lengthened and the inclination of the taper may be loosened. However, if this is done, it is against the demand for miniaturization of the die 14. By the way, diameter 200
A taper angle of 15 degrees is used to smoothly insert about 500 bundles of μ optical fibers into the tapered cap 14 having an inner diameter of 5 mm and a wall thickness of 0.7 to 1 mm.
A tapered portion having a taper length of 3 to 4 mm is required. The length of the parallel portion of the tip of the bundle fiber 11 is usually about 5 to 10 mm. ． When the bundle fiber is forcibly pushed into the tapered mouthpiece 17, the bundle fiber 11 is pushed along the taper angle of the mouthpiece 17 so that the bundle fiber 11 becomes oblique (with an angle), and the angled portion Easily damaged from.

An object of the present invention is to provide a base attachment structure for a bundle fiber, in which the bundle fiber can be easily inserted, the optical fibers of the bundle fiber are not easily scratched, and the base can be miniaturized.

[0008]

As shown in FIG. 1, a bundle fiber attachment structure for a bundle fiber according to the present invention includes an end portion 2 of a bundle fiber 1 formed by converging a large number of optical fibers.
The cap 3 having a small inner diameter is sequentially inserted into two or more cylindrical bases 3 having a uniform inner diameter in the axial direction and different in inner diameter so that the cap 3 having a smaller inner diameter is on the tip side.

[0009]

In the bundle fiber mouthpiece mounting structure of the present invention, the end portion 2 of the bundle fiber 1 is provided with two or more cylindrical mouthpieces 3 whose inner diameters are uniform in the axial direction and whose inner diameters are different from each other. Since the fibers are sequentially inserted so that they come to the tip side, the bundle fiber 1 which is scattered only by being converged is naturally arranged in the array by being inserted into the cap 3 having a larger inner diameter, and the outer diameter is The size of the optical fiber becomes smaller, and then the optical fiber is further inserted into the base 3 having an inner diameter smaller than that of the base 3 to further align the arrangement of the optical fibers, thereby further reducing the outer diameter. Therefore, finally, the bundle fiber can be smoothly inserted into the base 3 having a small inner diameter.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure for attaching a spinneret of a bundle fiber of the present invention will be described in detail with reference to the embodiment shown in FIG. 1 in FIG. 1 is a bundle fiber formed by converging a large number of optical fibers in which silicon is coated on the outer circumference of a glass fiber, 2
Is the end. The silicon coating layer of each optical fiber is peeled off from the end portion 2, and the length thereof is about 3 to 5 mm.

Reference numeral 3 denotes a mouthpiece that is inserted into the end portion 2 of the bundle fiber 1. All of the mouthpieces 3 have an inner diameter that is uniform in the axial direction. The inner diameter of each base 3 is gradually smaller on the tip side than on the bundle fiber 1 side. Each base 3 has a length of about 1 mm and an inner diameter slightly larger than the outer diameter of the bundle fiber 1 to be inserted.

In the present invention, the number of caps 3 used is not particularly limited, but about 2 to 4 is suitable in relation to the length of the end 2 of the bundle fiber 1. The base 3 and the end portion 2 of the bundle fiber 1 inserted therein are bonded with an adhesive.

[0013]

The bundle fiber attachment structure of the present invention has the following effects. ． Since the outer diameter of the bundle fiber 1 naturally becomes smaller each time it is inserted into the mouthpiece 3, finally it can be easily inserted into the mouthpiece 3 having a small inner diameter and the workability is improved. ． Even if several caps 3 are used, the total length thereof can be made shorter than that of the tapered cap, so that the cap 3 can be miniaturized. ． Since the tolerance between the inner diameter of the base 3 and the outer diameter of the bundle fiber 1 can be reduced, the filling rate is increased, and the base 3 can be downsized also from this point.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an example of a structure for attaching a spinneret of a bundle fiber of the present invention.

FIG. 2 is an explanatory diagram showing a usage example of a conventional light guide.

FIG. 3A is a front view of a base portion of a conventional light guide, and FIG. 3B is a cutout explanatory view of the base portion of the light guide.

FIG. 4 is a vertical cross-sectional explanatory view of a conventional structure for attaching a spinneret of a bundle fiber.

FIG. 5 is a vertical cross-sectional explanatory view of a conventional tapered die.

[Explanation of symbols]

 1 bundle fiber 2 end 3 base

Claims (1)

[Claims] 1. An end portion 2 of a bundle fiber 1 formed by converging a large number of optical fibers is inserted into two or more cylindrical ferrules 3 each having a uniform inner diameter in the axial direction and different inner diameters. 3. A structure for attaching a bundle fiber base, wherein 3 is sequentially inserted so that the tip end side is provided.