JPH06118280A - Method for manufacturing ferrule for single-core optical fiber connector - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a method of manufacturing a ferrule for a single-fiber optical fiber connector having excellent dimensional accuracy. [Structure] The outer peripheral surface of the ferrule material is ground by supporting the ferrule material by pushing the tip end portions of the tailstock centers into both open ends of the insertion hole of the ferrule material having an optical fiber insertion hole. In the method for manufacturing a ferrule for a single-fiber optical fiber connector, the tip portion 2 of the tailing center is made of single crystal diamond to avoid abrasion of the tailing center tip portion 2. Further, the shock absorbing material 6 is filled in the open end 5 of the ferrule material to soften the shock when the tip portion 2 of the tailstock center is pushed into the open end 5 of the ferrule material, and Prevent damage. Accordingly, the rotation of the ferrule material 3 does not occur during grinding, and a ferrule for a single-fiber optical fiber connector having excellent dimensional accuracy is manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a ferrule for a single-core optical fiber connector which is excellent in dimensional accuracy.

[0002]

2. Description of the Related Art A ferrule for an optical fiber connector such as FC type, SC type, FDDI type, etc. is an optical fiber fixing tool for fixing an optical fiber terminal portion and properly performing optical coupling between optical fibers. is there. The structure of this ferrule is such that a large diameter hole portion for holding the optical fiber core wire and a small diameter hole portion for fixing the exposed optical fiber by stripping off the coating of the end portion of the optical fiber core wire are linearly formed. It has a continuous through hole (hereinafter referred to as an optical fiber insertion hole).
Then, an optical fiber having a core of several μmφ is inserted into the small-diameter hole portion of the optical fiber insertion hole, and the cores of the end faces of the optical fiber are connected with their optical axes aligned. Therefore, the accuracy of submicron order is required for the matching of the inner and outer circumferences of the ferrule and the inner and outer circumference diameters. Further, as a part of improving dimensional accuracy, ceramics such as zirconia and alumina having a small coefficient of thermal expansion have come to be used as the material.

Such a ferrule for a single-core optical fiber connector is manufactured by forming an optical fiber insertion hole in advance and grinding the outer peripheral surface in accordance with the axis of the insertion hole. That is, as shown in FIG.
The ferrule material 3 having the optical fiber insertion hole 4 is pushed into the open end portions 5 of the insertion hole 4 respectively, and the tip portions 2 of the tailstock centers are pushed into the ferrule material 3 to support and rotate the ferrule material 3. The grinding stone 7 is rotated on the outer peripheral surface in a direction opposite to the rotation direction of the ferrule material 3 to bring them into contact with each other to grind.

[0004]

By the way, in such a grinding method, the diameter of the open end portion 5 of the ferrule material 3 is as small as 125 μmφ (outer diameter of the optical fiber), and the grindstone 7 is attached to this thin portion. Since the pressing force is concentrated and the tailing center 1 is made of cemented carbide and has a lower hardness than the ferrule material 3 made of ceramics, the tailing center 1 is abraded, and if worn, the ferrule material 3 will be rotated during grinding. However, there is a problem in that the dimensional accuracy of the obtained ferrule deteriorates. For this reason, a method of tapering the open end of the ferrule material into a shape that makes surface contact with the tip of the tailstock center was proposed (Japanese Patent Laid-Open No. 63-127865), but sufficient effect was not obtained. It was

[0005]

The present invention has conducted extensive studies in view of such a situation, and wear of the tailing center can be avoided by using a single crystal diamond in a portion in contact with the ferrule material. It has been found that a new problem that the opening end is damaged by impact when the diamond tailing center is pushed into the opening end of the ferrule material can be prevented by filling the opening end with an impact absorbing material. After further research, the present invention has been completed. That is, according to the present invention, the outer peripheral surface of the ferrule material is supported by pushing the tip end portions of the tailstock centers into both open ends of the insertion hole of the ferrule material having the optical fiber insertion hole to support the ferrule material. In the method for manufacturing a ferrule for a single-fiber optical fiber connector that grinds, the tip of the tailing center that contacts the opening end of the insertion hole of the ferrule material is made of single crystal diamond, and the ferrule material before pushing the tailing center The shock absorbing material is filled in the opening end of the optical fiber insertion hole.

In the method of the present invention, the tip portion of the tailing center is made of single crystal diamond having high hardness to avoid abrasion of the tip portion of the tailing center, and the tailing center made of the single crystal diamond is opened in the ferrule material. The problem that the opening end is damaged due to the impact when it is pushed into the end is solved by pressing the impact absorbing material into the opening end. The breakage of the opening end also causes a rotational shake of the ferrule material during grinding. The impact absorbing material is required to be a material that does not damage the tailing center, allows the tailing center to gradually enter, and can be easily removed after grinding is completed. For example, pine resin or synthetic resin is suitable. In the method of the present invention, it is not necessary to configure the entire tailing center with single crystal diamond, and it is preferable to locally configure only the portion that comes into contact with the open end of the ferrule material with single crystal diamond to reduce the cost. In order to bond the single crystal diamond to the base material of the tailing center, a usual method using an adhesive or the like can be applied. The opening end of the ferrule material on the side through which the optical fiber core wire is inserted is less likely to be worn due to the larger diameter, and the impact force at the time of pushing is also dispersed, so the method of the present invention to this opening end Does not necessarily have to be applied.

[0007]

In the method of the present invention, the ferrule material is supported by pushing the tip end portions of the tailstock centers into both open ends of the insertion hole of the ferrule material having the optical fiber insertion hole. In the method of manufacturing a ferrule for a single-fiber optical fiber connector in which the outer peripheral surface is ground, the tip of the tailing center that comes into contact with the opening end of the insertion hole of the ferrule material is made of single-crystal diamond, so that the tailing center is not worn. Avoided. Further, since the opening end of the ferrule material is filled with the impact absorbing material, the impact applied to the opening end when the tailing center is pushed into the opening end is alleviated and the opening end is damaged. do not do. Accordingly, a grinding process without blur is performed, and a ferrule for a single-fiber optical fiber connector having excellent dimensional accuracy can be obtained.

[0008]

EXAMPLES The present invention will be described in detail below with reference to examples. FIG. 1 is an explanatory view of a main part showing one aspect of the method of the present invention. The tip portion 2 of the tailing center 1 is made of single crystal diamond, and the opening end portion 5 of the optical fiber insertion hole 4 of the ferrule material 3 is filled with a synthetic resin as a shock absorbing material 6. As described above, since the portion of the tail end portion 2 of the tailing center that comes into contact with the ferrule material opening end portion 5 is made of single-crystal diamond having high hardness, the tail end portion 2 of the tailing center is not worn and the opening of the ferrule material is prevented. Since the end portion 5 is filled with the shock absorbing material 6, the impact when the tip portion 2 of the tailing center is pushed into the opening end portion 5 of the ferrule material is mitigated, and the opening end portion 5 is prevented from being damaged. A ferrule for a single-fiber optical fiber connector, which has been subjected to a grinding process without blurring and has excellent dimensional accuracy, has been manufactured.

[0009]

As described above, according to the method of the present invention, it is possible to manufacture a ferrule for a single-fiber optical fiber connector which is excellent in dimensional accuracy, and has a remarkable industrial effect.

[Brief description of drawings]

FIG. 1 is an explanatory view of a main part showing one mode of a method for manufacturing a ferrule for a single-fiber optical fiber connector of the present invention.

FIG. 2 is an explanatory diagram of a method for manufacturing a ferrule for a single-fiber optical fiber connector.

[Explanation of symbols]

 1 Tailstock Center 2 Tip of Tailstock Center 3 Ferrule Material 4 Optical Fiber Through Hole 5 Open End of Ferrule Material 6 Shock Absorber 7 Grindstone

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Takayuki Sudo 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd.

Claims (1)

[Claims] 1. A ferrule material having an optical fiber insertion hole formed therein, the tip end portion of a tailing center being pushed into both open ends of the insertion hole to support the ferrule material,
In the method of manufacturing a ferrule for a single-fiber optical fiber connector, which grinds the outer peripheral surface of the ferrule material, the tip portion of the tailing center that comes into contact with the insertion hole opening end of the ferrule material is made of single crystal diamond, and the tailing center is formed. A method for manufacturing a ferrule for a single-fiber optical fiber connector, characterized in that the opening end portion of the optical fiber insertion hole of the ferrule material before pushing in is filled with a shock absorbing material.