JPH01210908A - Ferrule for optical connector - Google Patents

Abstract

PURPOSE:To greatly simplify the adhering and assembling work and to prevent decentering by setting the diameter of the minor axis of an elliptic through hole provided in the center part to a value approximately equal to the diameter of an optical fiber and preliminarily providing a hot melt adhesive on the major axis side. CONSTITUTION:With respect to a field assembling type ferrule for optical connec tor, an elliptic through hole 5 is provided in the center part of a ferrule main body 4 consisting of glass. A diameter H of its minor axis is made approximate ly equal to the diameter of an optical fiber 6, and a hot melt adhesive is prelimi narily provided on the major axis side. At the time of assembling the ferrule, the optical fiber 6 is inserted through the hole 5 and is adhered and fixed by heating. Consequently, conventional agitating and coating of a two-component adhesive are omitted and the assembling work is greatly simplified. Since the diameter of the minor axis is approximately equal to the diameter of the optical fiber, decentering is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a ferrule for an optical connector, and particularly to a ferrule for an optical connector that can be assembled on site.

[Conventional technology]

As shown in Fig. 2, ferrules for on-site assembly type optical connectors that have been proposed in the past have a circularity mark at the center of a cylindrical ferrule body 1 made of glass, ceramic, metal, hard plastic, etc. It had a structure in which a circular through hole 2 with a high height was provided.

By the way, when assembling an optical connector using the above-mentioned optical connector ferrule, prepare the optical fiber 3 whose terminal has been treated in advance, and insert the bare wire part of this optical fiber 3 into the through hole 2 of the phenol body 1. They were tightly fixed to each other using an adhesive (not shown).

[Problem to be solved by the invention]

However, since conventionally a two-component adhesive is used, it must be thoroughly stirred, and this adhesive must be applied inside the through hole 2 of the ferrule body l or on the surface of the optical fiber 3. It had to be applied, which required a tedious work process.

Further, depending on the amount of adhesive, the optical fiber 3 may be held eccentrically in the ferrule body 1, which has a negative effect on quality.

SUMMARY OF THE INVENTION An object of the present invention was made in view of the above-mentioned drawbacks, and it is an object of the present invention to provide a ferrule for an optical connector that is easy to assemble and prevents the optical fiber from being held eccentrically.

[Means to solve the problem]

In the optical connector ferrule according to the present invention, the cross-sectional shape of the through hole provided in the center is elliptical, and the minor axis diameter of the elliptical through hole is formed to be approximately equal to the diameter of the optical fiber, and the ferrule is elliptical. The configuration is such that a hot-melt adhesive is previously provided on the long axis side of the through hole.

[Effect]

In this way, the present invention has a structure in which hot-melt adhesive is applied in advance on the long axis side of the oval through hole, so the troublesome work of applying adhesive during assembly can be eliminated, and the work process can be simplified. It can be significantly shortened. Further, since the short axis diameter of the elliptical through hole is formed to be approximately equal to the diameter of the optical fiber, there is no possibility that the optical fiber will be installed eccentrically within the elliptical through hole.

〔Example〕

Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

FIG. 1 is a cross-sectional view showing one embodiment of a ferrule for an optical connector according to the present invention.

A through hole 5 having an oval cross-sectional shape is provided in the center of the glass ferrule body 4, and the short axis diameter H of the through hole 5 is formed to be approximately equal to the diameter of the optical fiber 6. ing. Further, a hot melt adhesive 7 is provided in advance on the long axis side of the oval through hole 5, and the shape of the through hole 5 is shaped into a circle approximately equal to the diameter of the optical fiber 6 by the hot melt adhesive 7. It is designed to take on a shape. In this example, the diameter of this hole was approximately 127 μm.

When assembling an optical connector using the optical connector ferrule configured as described above, first, the optical fiber 6 whose terminal has been treated in advance is inserted into the through hole 5 of the ferrule body 4 made of glass. At this time, since the hot melt adhesive 7 is provided on the long axis side of the through hole 5, the hole shape of the through hole 5 is circular, and the optical fiber 6 is shaped with the hot melt adhesive 7. It is now inserted into the circular hole made. Thereafter, by heating the glass ferrule body 4 with a heater (not shown), the hot melt adhesive 7 provided inside the through hole 5 is heated, and the hot melt adhesive 7 is melted. An optical fiber 6 is adhesively fixed in the through hole 5. After this, the hot-melt adhesive 7 is allowed to harden naturally, and the next step is performed to complete the assembly of the optical connector, thereby making it possible to significantly shorten the assembly time compared to the conventional method.

〔Effect of the invention〕

As explained above, according to the ferrule for an optical connector according to the present invention, since the hot-melt adhesive is provided in advance on the long axis side of the oval through hole, it is not necessary to stir the adhesive during assembly as in the conventional case. Alternatively, it is possible to eliminate the troublesome work of applying the coating inside the ferrule or on the surface of the optical fiber, which has the effect of greatly simplifying the work process. In addition, since the cross-sectional shape of the through-hole is elliptical and the minor axis diameter of this elliptical through-hole is approximately equal to the diameter of the optical fiber, the optical fiber is held and fixed within the ferrule with high precision, resulting in quality It is also possible to improve the

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of a ferrule for an optical connector according to the present invention, and FIG. 2 is a cross-sectional view showing an example of a conventional ferrule for an optical connector. 4... Ferrule body, 5... Through hole, 6... Optical fiber, 7... Hot melt adhesive.

Claims (1)

[Claims] The cross-sectional shape of the through-hole provided in the center is elliptical, and the minor axis diameter of this elliptical through-hole is approximately equal to the diameter of the optical fiber, and the long axis side of the elliptical through-hole is pre-heated. A ferrule for optical connectors featuring an adhesive.