JPS61267007A - Optical fiber connector - Google Patents

Abstract

PURPOSE:To reduce the size of an optical fiber connector and to improve the reliability and economy of assembling operation by inserting an optical fiber cable into the through hole of an elastic member, and clamping a fiber layer loosely between the tapered surface of a plug body and the tapered surface of the elastic member and then engaging a clamping box nut with the plug body threadably. CONSTITUTION:The optical fiber cable is run through the clamping box nut 20 and elastic member 17 previously. The optical fiber element wire 1, the 2nd layer coating part 2, and the fiber layer 3 are treated, the end surface of the 3rd layer coating part 4 is set on the same plane with the end surface of the elastic member 17, and the outer peripheral part of the 3rd layer coating part 4 is adhered in the hole of the elastic member 17. An adhesive is applied to the optical fiber element wire 1 and the 2nd layer coating part 2, which are inserted into corresponding hole parts 6 and 7 of a ferrule 5 and adhered. The clamping nut 20 is forced into the tapered and stepped hole 15 of the elastic member 17 and the tapered surfaces 15a and 18 are pressed tightly against the fiber layer 3, which is clamped. Further, the outer periphery of the 3rd layer coating part 4 is pressed and fixed tightly with the stress generated when the elastic member 17 deforms toward the hole.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an optical fiber connector for communications, and more particularly to an optical fiber connector having a structure that allows an optical fiber cable to be easily attached to an optical connector plug.

(Prior Art) First, the configuration and functions of commonly used optical fiber cables will be briefly described.

Optical fibers mainly have a structure in which silica glasses each having a different refractive index and each having a diameter of 125 microns are integrated concentrically around the outer periphery of a core layer having a diameter of 10 to 50 microns.

As described above, the fine optical fiber wire made of quartz glass is weak against tension and bending due to its material properties, so the outer periphery is coated to prevent it from being easily damaged.

Normally, three layers are formed around the outer periphery of an optical fiber wire having a diameter of 125 microns to regulate the bending radius and prevent damage to the optical fiber wire due to bending stress. The first layer is a silicone rubber-based thin buffer layer, and the second layer is a nylon-based covering material with a diameter of 0.9 va.
The third layer is a nylon-based cylindrical covering layer with an inner diameter of 1°5fi and an outer diameter of 3°. To deal with tensile stress, by interposing a polyamide fiber layer between the second and third layers and adhesively fixing it to one end of the optical fiber connector plug, tensile stress does not act on the optical fiber wire. It is considered that there will be no

FIG. 4 is a diagram showing an installation procedure for attaching an optical fiber cable using an optical connector plug of a conventional optical fiber connector, and FIG. 5 is a sectional view showing a completed example of the conventional optical fiber connector.

In Fig. 4, 1 is an optical fiber made of quartz glass with a diameter of 125 microns, and 2 is a second optical fiber with a diameter of 0.9 µm.
A layer covering part, 3 is a fiber layer, 4 is a third layer covering part with a diameter of 3, 5 is a ferrule, 6 is a microhole with a diameter of 126 microns for attaching the optical fiber 1 to the tip of the ferrule 5, 7 8 is a hole with a diameter of 1 mm for inserting the second layer covering part 2 having a diameter of 0.9 m, 8 is a cap nut for engaging and attaching the optical connector plug to a sleeve adapter (not shown), 9 is a plug body, 10 11 is a fiber layer adhesive part that adheres the fiber layer 3 to the plug body 9, and a hole 1 that fits into the fiber layer adhesive part 10.
2 and an adhesive member provided with a hole 13 through which the optical fiber cable is passed; 14 is a boot made of an elastic material such as rubber for the purpose of buffering the bending stress of the optical fiber cable.

Next, the procedure for attaching the optical fiber cable will be explained.

First, an optical fiber cable is passed through the holes in the adhesive member 11 and the boot 14 in advance. Next, the optical fiber wire 1
．． An epoxy adhesive is applied to the outer peripheral surface of the second layer covering part 2, and the second layer covering part 2 is inserted into the holes 6 and 7 of the ferrule 5 and bonded. Furthermore, the fiber layer adhesive part 10°, the third layer covering part 4 and the adhesive member 1
1. An adhesive is applied to the joint of the boot 14, and the fibrous layer adhesive part 10 is inserted and fixed into the adhesive member 11 to complete the integration and installation (FIG. 5). Thereafter, the end face of the ferrule 5 integrated with the optical fiber cable is polished.

The optical fiber cable installation method described above has been widely used as the most reliable method.

(Problem to be Solved by the Invention) However, in this method, unless the adhesive part of the ferrule 5 is sufficiently hardened before assembly, the optical fiber 1 is likely to be damaged. Since the work of adhering and integrating the covering portion 4 cannot be done immediately, there is a problem in that the adhesion process is divided into two steps.

In addition, in the second bonding process, it is necessary to sufficiently pull out the fiber N3 and bond it to the fiber layer bonding part 10 while removing play, but at this time, the optical fiber cable is not yet fixed to the plug body 9. In order to compress the second layer covering part 2, bend it.

There is a problem in that stress such as torsion is likely to be applied, and adhesion requires skill.

Furthermore, when adhesive is used, if the adhesive adheres to an unnecessary area, the area must be cleaned and removed, which increases the number of work steps.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical fiber connector that can easily and reliably attach an optical fiber cable to an optical fiber connector plug in one step.

(Means for Solving the Problems) In order to achieve the above object, an optical fiber connector according to the present invention includes an optical fiber plug having a ferrule attached to one end, and an optical fiber having a fiber layer on its coating from the other end. An optical fiber connector for attaching a cable has a plug body that has a through hole in the center, a tapered surface on the inner periphery at one end of the through hole, and a threaded part on the outer periphery, and a plug body that has a through hole in the center and has a threaded part on the outer periphery. an elastic member having a tapered surface that contacts the tapered surface of the plug body and a flange portion provided at one location on the outer peripheral surface; a threaded portion having a through hole in the center and screwed into the threaded portion of the plug body; The tightening device is provided with a flange portion that contacts the flange portion of the elastic member, and includes a cap nut, and the front optical fiber cable is inserted into the through hole of the elastic member;
After the fiber layer is loosely sandwiched between the tapered surface of the plug body and the tapered surface of the elastic member, the tightening is performed by pressing the flange of the elastic member with the flange of the cap nut. The plug body is configured to be screwed into the plug body.

(Function) Since the present invention is constructed as described above, the optical fiber cable can be tightened with a cap nut in advance.

Insert the elastic member in this order, apply adhesive to the optical fiber and the second layer coating, align the end surface of the third layer coating with the end surface of the elastic member, and then attach the fiber layer to the outer periphery of the elastic member. Bend it to a tapered surface, insert the tip of the optical fiber into the hole of the ferrule, and with the end of the optical fiber slightly protruding from the end surface of the ferrule, most of the tapered surface of the elastic member is inserted into the tapered surface of the plug body. After that, tightening is done by screwing the cap nut onto the plug body, causing elastic deformation of the joint of the elastic member to the plug body, and causing the fiber layer to come into contact with the tapered surface of the plug body and the tapered surface of the elastic member. In addition to being firmly held by pressure, the third layer coating also acts to tighten and fix the entire circumference more firmly.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings and the like.

Fig. 1 is a diagram showing the installation procedure for attaching an optical fiber cable with the optical connector plug of the optical fiber connector according to the present invention, and Fig. 2 is an explanation showing the installation principle of the optical fiber cable of the optical fiber connector according to the present invention. Figure, 3rd
The figure is a sectional view showing a completed example of the optical fiber connector according to the present invention.

First, the structure of the optical fiber connector of the present invention will be explained.

Note that the same reference numerals are given to parts having the same functions as those of the conventional example described above.

In FIG. 1, 9a is a plug body, 17 is an elastic member,
20 is tightened with a bag nut.

The plug body 9a is provided with a tapered stepped hole 15 on the inner diameter side of one end and a threaded portion 16 on the outer diameter side. Elastic member 1
7 is a cylindrical member, with a tapered surface 1 on the outer periphery of one end.
8 is provided, and a flange 19 is provided in connection with the tapered surface 18 thereof. For tightening, the cap nut 20 is provided with a threaded part 21 on the inside.
can be screwed together with the threaded portion 16 of the plug body 9a.

A flange 22 is formed at the other end of the cap nut 20, and this flange 22 is connected to a flange surface 23 of the elastic member 17.
Make face-to-face contact with the person.

Next, the installation procedure will be explained. The optical fiber cable is preliminarily threaded through the tightening ring (20) and the elastic member 17. The optical fiber strand 1, the second layer coating section 2, and the fiber layer 3 are treated as shown, and the end surface of the third layer coating section 4 is made flush with the end surface of the elastic member 17, and the third layer coating section is formed. The outer peripheral portion of 4 is glued to the hole of the elastic member 17. An adhesive is applied to the optical fiber wire 1 and the second layer coating portion 2, and the adhesive is inserted into the corresponding holes 6 and 7 of the ferrule 5 and bonded. At this time, the fiber layer 3 is loosely sandwiched between the tapered surface 15a of the tapered stepped hole 15 of the plug body 9a and the tapered surface 18 of the elastic member 17. In this state, tightening is performed by pushing the elastic member 17 into the tapered stepped hole 15 using the nut 20, so that the tapered surfaces 15a and 18 are firmly crimped together with the fiber layer 3 sandwiched therebetween. Further, the outer periphery of the third layer covering portion 4 can also be firmly crimped and fixed by the stress that causes the elastic member 17 to deform toward the hole side.

FIG. 2 shows the state of deformation of the tapered surface 18 of the elastic member 17 by the tightening nut 20; the upper half shows the previous state of tightening, and the lower half shows the state of tightening and compression. It shows. The length of the outer peripheral tapered surface 18 of the elastic member 17 is
10~ than the depth of the tapered surface 15a of the tapered stepped hole 15
It is set about 20% larger. Since the outer periphery of the elastic member 17 is regulated by the tapered surface 15a, the elastic member 17 is deformed in an arc shape in the direction of the arrow on the inner diameter side by an amount corresponding to the tightened and compressed volume. Actually, since the optical fiber cable is inserted into the hole of the elastic member 17, this deformation acts on both the inner diameter side and the outer diameter side, and it is possible to firmly fix the fiber layer 3 and the optical fiber cable together. become.

Furthermore, by folding the fiber layer 3 before inserting it into the tapered surface 18 of the elastic member 17, the force pulled out from the optical fiber cable acts automatically as it is inserted, and the play can be uniformly removed. .

Furthermore, since the adhesive is used only for adhering the ferrule part, and the fiber layer 3 is press-fitted on the tapered surface, the adhesive is applied only to the adhesive part of the ferrule 5 and the plug body 9a is attached as it is. By inserting the cap nut into the cap nut and tightening the cap nut, assembly can be completed in step ①. As a result, the number of man-hours is reduced to more than half, and the work that requires skill is eliminated.

FIG. 3 shows the state of the optical fiber connector according to the present invention upon completion of assembly. Comparing the optical fiber connector according to the present invention with the conventional example shown in FIG.
The part that fixes the cable and the part that supports the optical fiber cable are folded back and folded together, making the overall length short and allowing for a compact design and manufacture.

(Effects of the Invention) As described above in detail, according to the present invention, the optical fiber connector has a simple structure, and the adhesive assembly work that conventionally required two steps can now be performed in one step. .

Furthermore, the assembled optical fiber connector can now be significantly miniaturized.

Furthermore, the work can be done reliably without requiring any skill,
The reliability and economy of assembly work has been significantly improved.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the installation procedure for attaching an optical fiber cable with the optical connector plug of the optical fiber connector according to the present invention, and Fig. 2 is an explanation showing the installation principle of the optical fiber cable of the optical fiber connector according to the present invention. Figure, 3rd
The figure is a sectional view showing a completed example of the optical fiber connector according to the present invention. FIG. 4 is a diagram showing an installation procedure for attaching an optical fiber cable using an optical connector plug of a conventional optical fiber connector, and FIG. 5 is a sectional view showing a completed example of the conventional optical fiber connector. 9a...Plug body 17...Elastic member 20...
・Fukuronatsu Patent Applicant Seiko Giken Co., Ltd. Agent Patent Attorney Inoro Mizogata 1 Figure 22 Figure 3

Claims (1)

[Claims] An optical fiber connector that has a ferrule attached to one end and connects an optical fiber cable having a fiber layer to the sheath from the other end of the plug has a through hole in the center and an inner periphery of the one end of the through hole. A plug body having a tapered surface with a threaded portion on the outer periphery, a through hole in the center, a tapered surface that contacts the tapered surface of the plug body at the tip of the outer peripheral surface, and a flange portion at one location on the outer peripheral surface. It consists of an elastic member, a tightening cap nut having a through hole in the center, a threaded part that screws into the threaded part of the plug body, and a flange part that comes into contact with the flange part of the elastic member. After inserting the optical fiber cable into the hole and loosely sandwiching the fiber layer between the tapered surface of the plug body and the tapered surface of the elastic member, the flange portion of the elastic member is pressed by the flange portion of the tightening cap nut. The optical fiber connector is characterized in that the tightening cap nut is configured to be screwed onto the plug body.