JPS59204814A - Connecting structure of optical connector - Google Patents

Abstract

PURPOSE:To obtain an inexpensive and simple structure which is capable of fitting with high accuracy a pair of optical fibers by placing oppoaingly a pair of ferrules of an optical fiber, in a springy triangle pole-shaped sleeve having a long groove like a circular arc. CONSTITUTION:A slit is not formed on a triangle pole-shaped sleeve 5, and also a diameter of the inscribed circle is formed so as to be a little smaller than the outside diameter of a ferrule 2. Also, a circular arc-shaped recessed groove 7 having a radius of curvature which is smaller than a radius of curvature of the ferrule 2 is formed on the inside surface of the sleeve 5. When the ferrules 2 are pressed in from both ends of this sleeve 5 and placed so as to be opposed to each other, the ferrule 2 is clamped from three sides by springiness of the sleeve 5 and held stably also clamped extending over a wide surface by the groove 7, and it is possible to obtain a connecting structure which is capable of holding an optical fiber with high accuracy, is inexpensive and also manufactured easily.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical connector connection structure for arranging and connecting ferrules having fixed optical fiber ends facing each other on the same axis.

Optical connectors are used to connect waveguides such as optical fibers or between waveguides and light emitting/light receiving elements, etc., but the most important function is to connect the waveguides to be connected, Alternatively, it is possible to align the waveguide and the light emitting/receiving element with high precision.

For example, in connecting waveguides to each other, it is necessary to hold and fix the waveguides and ferrules by aligning the axes of each waveguide accurately with the center axis of the ferrule. The connection sleeve built into the optical connector has the function of arranging the ferrules with high precision and stably holding the connected ferrules.

As a connection structure of a conventional optical connector, a sleeve 3 having a cylindrical shape and having one axially parallel slit 1 as shown in FIG. 1(a) is generally used. A structure is adopted in which the ferrule 2 is inserted from there. However, in such a sleeve with a slit, when forming the slit 1, the through hole 4 of the sleeve 3 is
The uniformity of the shape and the roundness in the cross section or the straightness in the axial direction are likely to be lost, as shown in Fig. 1(b).
To .

As shown in an exaggerated manner, it is difficult to hold the ferrule 2 uniformly and concentrically on both ends. That is, in the conventional optical connector connection structure, the contact between the ferrule and the sleeve tends to be incomplete, and the connection tends to be unstable.

Furthermore, forming such a slit 1 in the sleeve 3 requires high-precision and large-scale mechanical equipment, and the quality is affected by the skill level of the operator, resulting in poor manufacturing yields. There was a drawback which was the price.

An object of the present invention is to eliminate the above-mentioned drawbacks of the conventional technology and to provide an optical connector connection structure that is inexpensive, simple in structure and manufacture, and capable of fitting a pair of ferrules to be connected in a connector with high precision. There is a particular thing.

The optical connector connection structure according to the present invention is constructed by fitting a ferrule into a triangular prism-shaped sleeve having spring properties.

In this case, in order to further enhance the effect of the triangular prism-shaped sleeve, a concave groove-like arc having an inner diameter smaller than the outer diameter of the ferrule is formed on the inner surface of each side of the sleeve parallel to the central axis of the sleeve. It is better to do so. Note that the actual optical connector structure may consist of an adapter consisting of a plug that combines a ferrule with a coupling nut, etc., and a housing, etc., which has a mechanism for engaging the coupling nut on the triangular prism-shaped sleeve. Of course, many such embodiments are also included in the present invention.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2(a) is an exploded perspective view of an optical connector connection structure according to an embodiment of the present invention, and corresponds to the conventional example shown in FIG. 1(a). FIGS. 2(b) and 2(c) are cross-sectional views of two embodiments of the present invention. As shown in FIG. 2(b), in the embodiment of the present invention, the sleeve 5 is formed of an elastic cylinder having a triangular cross section,
Its peripheral surface (side surface along the axial direction) is shown in Figure 1 (a),
A slit as shown in (b) is not formed. The hollow portion 6 of the triangular prism-shaped sleeve 5 is formed so that the diameter of its inscribed circle is slightly smaller than the outer diameter of the ferrule 2 to which it is applied. In other words, the ferrule 2, which is slightly larger than the inscribed circle specific to the triangular prism sleeve, is press-fitted into the triangular prism sleeve 5. As a result, the triangular prism-shaped sleeve 5 spreads uniformly in three directions due to its own springiness, and its repulsive force (indicated by reference numeral 8) tightens the ferrule 2 from three directions, thereby stably holding the ferrule 2. do. Moreover, since there are no slits or the like formed as in the conventional case, the sleeve is formed with the same cross-sectional dimensions over the entire length, and its spread is not uneven as in the conventional case, so the ferrules that are press-fitted from both ends are aligned on the same axis. is held accurately.

In the embodiment shown in FIGS. 2A and 2C, arc-shaped grooves 7 extending parallel to the axial direction are formed on three inner surfaces of the triangular prism-shaped sleeve 5, respectively. In this case, the inner diameter of the concave groove 7 is formed so that it is also slightly smaller than the outer diameter of the ferrule 2, and this results in a repulsive force due to elastic expansion when the ferrule is press-fitted, as in the case of FIG. The ferrule is held stably and with high precision. Furthermore, in this case, the ferrule is tightened over a much wider surface as shown in FIGS. 13(a) and (c), so that even more stable and reliable holding and fixing can be achieved.

To manufacture such a triangular prism-shaped sleeve 5, it is only necessary to cut a cylindrical body such as an elastic pipe to a predetermined length and form it into a triangular prism shape by press processing, which requires fewer manufacturing steps than conventional sleeves. Since this method does not require much skill on the part of the operator, there are fewer variations in quality and fewer defective products, and lower prices are possible.

Figure 3 shows the ferrule 2 attached to the sleeve 5 shown in Figure 2(a).
A triangular prism-shaped sleeve was manufactured using the method described above, and the characteristics of an optical connector with a ferrule press-fitted were measured, and the performance was equivalent to or better than that of conventional sleeves with slits.

As explained above, according to the present invention, the optical fibers can be aligned uniformly on the plug '1 of the optical connector by the three-point support structure, so that the optical fibers are always held with a stable holding force, and high-precision counterfeiting is possible. This has the effect of providing a good connection. Further, since there is no need to process slits, it is extremely easy to manufacture, and has the advantage that it does not require any particular skill on the part of the operator.

[Brief explanation of the drawing]

FIG. 1(a) is an exploded perspective view showing a conventional optical connector connection structure using a slitted cylindrical sleeve, FIG. 1(b) is a cross-sectional view of the conventional structure, and FIG. An exploded perspective view of an optical connector connection structure according to an embodiment, FIG.
b) is a cross-sectional view according to another embodiment of the invention, FIG.
) is a cross-sectional view of the embodiment shown in FIG. 2(a) K, and FIG. 3 is a perspective view of the embodiment shown in FIG. 2(a) K in an assembled state. 2... Ferrule, 5... Triangular prism-shaped SJ
-F, 7... Arc-shaped groove. Agent Patent Attorney Rikichi Someyo Figure 1 (0) Figure 1 (b) Figure 3

Claims (2)

[Claims] (1) In an optical connector connection structure in which ferrules holding and fixing the ends of optical fibers are facing each other and connected on a coaxial line, the ferrules are arranged facing each other in a triangular prism-shaped sleeve having spring properties from both ends thereof. An optical connector connection structure characterized by: (2) A long arc-shaped groove having a radius of curvature smaller than the radius of curvature of the ferrule is formed on each three inner surfaces of the triangular prism-shaped sleeve parallel to the central axis of the sleeve. Optical connector connection structure described in Section 1.