JPS6191609A - Cable holding structure of optical fiber connector - Google Patents

Abstract

PURPOSE:To evade easy-to-break structure of a cable and to increase its mechanical strength by arranging a cylindrical elastic member inside the opening part of the cable holder of an optical connector plug in the lengthwise direction of the cable. CONSTITUTION:The cylindrical elastic member 6 is arranged in the opening part of a sleeve 5 formed integrally with an end part of the cable holder 1 in the lengthwise direction of the cable 1. Even when the cable 2 is applied with flexural tension, the fiber never breaks because the corner part of the elastic member 6 is gentle and even when the cable is held lengthwise, no foreign matter is put between the cable and elastic member 6, so the cable is not curved acutely by some foreign matter. Larger flexural force when applied is received by the sleeve 5. Therefore, the optical cable is prevented from breaking and the operativity of laying is improved to reduce unexpected accidents during the operation, thereby improving the reliability on the whole.

Description

TECHNICAL FIELD The present invention relates to a cable holding structure for an optical fiber connector (hereinafter abbreviated as optical connector) attached to the terminal end of an optical cable.

Prior art cables use optical fibers as conductors for transmitting signals. Optical fibers are generally made of glass as a main component and have a small diameter, but when they are made into cables, they are protected by various impact layers and become less likely to break when bent.

However, the locations where optical connectors are attached are frequently operated and are often subjected to not only bending but also tension, and there is a high risk of fiber breakage when bending at a small radius or radius. Therefore, sufficient care must be taken when handling it.

In the conventional cable holding structure, as shown in FIG. Take heat shrink tubing or something like that.

It covers the rubber tube 3. Note that 4 is a nut for fastening the connector.

In such a conventional structure, when a tensile force is applied to the cable 2 in a direction perpendicular to the axial direction of the optical connector, if the rigidity of the heat-shrinkable tube or the rubber tube 3 is small, as shown in FIG. 2(a), If the cable 2 bends at an acute angle from the end of the cable holding part 1, and the rigidity is too high, it will bend as shown in Fig. 2(b).
The cable 2 is bent at an acute angle from the end of the tube, and the optical fiber is likely to break at section A in FIG. 2(a) and section B in FIG.

It is also possible to prevent sharp bends by controlling the rigidity of the heat-shrinkable tube or rubber tube 3, but in the case of optical connectors that are frequently operated, the tube would have to be bent many times, and the external Cracks may occur due to scratches from scratches, etc., and after a certain period of time, sharp bends may occur, leading to fiber breakage.

Furthermore, Japanese Patent Application No. 157997/1984 4===Ilt
As shown in Figure 2, there is a cable holding end that is continuously expanded in diameter toward the open end, but in this case, since the open end is always open, there is a risk of foreign objects getting caught, and the cable can be left in that state. If the optical fiber is bent, a sharp bend may occur, leading to damage to the optical fiber.

OBJECTS OF THE INVENTION An object of the present invention is to provide a cable holding structure for an optical fiber connector that has high mechanical strength and avoids the disadvantage of the prior art in that the cable is susceptible to bending and tension.

Composition of the Invention In the cable holding structure of an optical fiber connector according to the present invention, a cylindrical elastic member is arranged along the longitudinal direction of the cable inside the opening of the cable holding part of the optical connector plug attached to the terminal end of the optical cable. It is characterized by

Example Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 3 is a side view, partially in cross section, showing one embodiment of the present invention, in which parts equivalent to those in FIG. 1 are designated by the same reference numerals. In the figure, a sleeve 5 is formed integrally with the end of the cable holding part 1, and inside the opening thereof, a cylindrical elastic member 6 is arranged along the longitudinal direction of the cable 2, and the end thereof is connected to the sleeve. It is placed so that it is located on the face of the 5th edge of 5.

According to this structure, even if a bending tension is applied to the cable 2, the wall surface of the cylindrical elastic member 6 inside the opening of the cable holding part 1 has a gentle curvature as shown in FIG. Because it deforms, it does not have sharp bends. Therefore, the optical fiber will not break. Further, even if a larger bending force is applied, the sleeve 5 made of a different material (for example, metal) than the elastic member 6 can absorb the force. Furthermore, even when the cable 2 is held straight in the longitudinal direction of the connector, if the outer diameter of the cable 2 and the inner diameter of the cylindrical elastic member 6 are made approximately equal, foreign objects etc. can be kept away from the cable 2 and the elastic member. 6, and there is no need to consider sharp bends caused by foreign objects or the like when bending the cable 2.

FIG. 4 shows another embodiment of the invention, except that the sleeve 7 is formed separately from the cable holding part 1 and is fitted onto the end of the cable holding part 1. It has the same configuration as the one in Figure 3.

FIG. 5 shows yet another embodiment of the invention.

In this embodiment, the cylindrical elastic member 6A is formed so that its thickness increases toward the open end, so that the curvature of the elastic member 6A can be made sufficiently large. According to this configuration, the cable 2 will not be bent at an acute angle at the end of the connector, and therefore the optical fiber will not be bent.

FIG. 6 shows yet another embodiment of the invention.

In this embodiment, the elastic member 6B is provided so as to protrude longer than the open end of the cable holding portion 1 (the open end of the sleeve 7), and its rigidity is formed so that it gradually decreases toward its free end.

Therefore, the cable 2 will not bend sharply at the end of the connector, and as a result the optical fiber will not break.

As described in detail, according to the present invention, bending of optical cables can be prevented, so work efficiency during installation of optical systems is significantly improved, and unexpected accidents during system operation are greatly reduced. This improves the reliability of the entire system.

[Brief explanation of drawings]

Fig. 1 is a side view including a partial cross section showing a conventional example, and Fig. 2 (
a>, (b) are diagrams showing the bent state of the cable, FIG. 3 is a side view including a partial cross section showing one embodiment of the present invention, and FIGS. 4 to 6 are other embodiments of the present invention. FIG. Explanation of symbols of main parts 1...I cable holding part 2...Cable 5.7...Sleeve

Claims (1)

[Claims] A cable holding structure for an optical fiber connector, characterized in that a cylindrical elastic member is arranged along the longitudinal direction of the cable inside an opening of a cable holding part of an optical connector plug attached to the end of an optical cable.