JPS6134124B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a terminal processing device for an optical fiber when connecting the optical fiber or attaching the optical fiber to a connector.

As shown in FIG. 1, an optical fiber core usually consists of an optical fiber 1, a primary coating 2, a buffer layer 3, and a secondary coating 4.
The optical fiber without the secondary coating 4 is called an optical fiber (indicated by reference numeral 5 in the drawings). The secondary coating 4 is made of a material such as nylon, which protects the optical fiber 5 and has a thick outer diameter to facilitate handling. Therefore, in actual sites, optical fibers are mainly used in the form of optical fiber cores with secondary coatings applied, and it is also customary to collect optical fiber cores in optical cables. . For this reason, article connectors for connecting optical fibers have been developed for optical fiber core wires.

By the way, optical cables having a structure in which a large number of optical fiber wires are assembled are currently being put into practical use. However, when connecting optical fiber wires or attaching connectors to such optical cables, a problem arises in that the above-mentioned conventional connecting articles and connectors cannot be used. Furthermore, when connecting optical fibers or attaching connectors, it is usually necessary to remove the primary coating and buffer layer, but the optical fiber wires are difficult to handle and may be damaged or broken during removal work.

The present invention makes it possible to connect optical fiber wires, attach them to connectors, etc. using connecting articles, connectors, etc. for optical fiber core wires, facilitate the handling of optical fiber wires, and The purpose is to facilitate the removal of coatings and buffer layers.

The gist of the present invention for achieving the above object is to provide a container for positioning the end of an optical fiber formed by coating an optical fiber with a primary coating and a buffer layer, and a container for positioning the end of the optical fiber by an appropriate distance from the end of the optical fiber. The present invention relates to an optical fiber end processing device comprising: a stopper for positioning a heat shrinkable tube; and a heating means for heating the heat shrinkable tube.

Hereinafter, the present invention will be explained in detail based on an embodiment shown in the drawings.

FIGS. 2a and 2b show the procedure for processing the terminal of an optical fiber. First, as shown in FIG. 2A, prepare a heat-shrinkable tube 6 of a predetermined length, insert it from the end of the optical fiber 5, and place it at a distance l from the end of the optical fiber 5. Arrange so that the end of the heat shrink tube 6 is facing. The length of the distance l is set to 20 to 50 mm in consideration of the cutting work of the optical fiber and the like. Next, only the heat-shrinkable tube 6 or the heat-shrinkable tube 6 and the optical fiber strand 5 are heated. The heat-shrinkable tube 6 is heated to a temperature (for example, about 100° C.) at which it contracts and coats the optical fiber strand 5. The optical fiber 5 is heated to an appropriate temperature (for example, about 200 to 300°C) to hydrolyze and easily remove the primary coating 2 and buffer layer 3. Ru. Therefore, in the case of an optical fiber whose primary coating 2 and buffer layer 3 can be easily removed without heating, heating of the strand can be omitted. As a heating method, the optical fiber strand and the heat-shrinkable tube 6 may be heated simultaneously, or the same heating means may be moved to heat them separately. Also, heat shrink tube 6
may be retracted entirely, but 5 to 6 cm from the terminal.
By shrinking the length, sufficient strength can be obtained for connection and connector installation work. In addition, since conventional connecting products and connectors for optical fiber core wires are used to connect the optical fiber bare wires after terminal treatment and to attach connectors, the outer diameter of the heat shrink tube 6 after shrinking is the same as that of the optical fiber core wires. It is desirable to match the outer diameter of (usually around 0.9mmφ).

FIG. 3 shows a schematic configuration of an embodiment of an optical fiber end processing apparatus according to the present invention. The container 7 that accommodates the optical fiber strand 5 and the heat-shrinkable tube 6 has a cylindrical shape with a bottom 8. A stopper 9 is provided within the container 7 at a position a suitable distance (corresponding to the distance l) from the bottom 8. Further, heating resistance wires 11 and 10 are provided in the container 7 at a position corresponding to between the bottom 8 and the stopper 9 and at a position corresponding to above the stopper 9, respectively. 12 and 13 are power supplies, 14 and 15 are variable resistors, and 16 and 17 are timers.

To process the end of an optical fiber using this device, the optical fiber 5 is passed through a heat shrink tube 6 and both are placed in a container 7. The optical fiber strand 5 is inserted until its end touches the bottom 8, and the heat shrink tube 6 is inserted until its end touches the stopper 9. At this time, the state of the optical fiber strand 5 and the heat shrinkable tube 6 is as shown in FIG. 2a. Note that any procedure may be used to achieve this state. For example, the heat shrink tube 6 is inserted into the container 7 first, and then the optical fiber 5 is inserted into the container 7.
You may also insert . Next, current is applied to the heat generating resistance wires 10 and 11 by the power sources 12 and 13 to generate heat, and the heat shrinkable tube 6 and the optical fiber bare wire 5 are heated.
heat up. Heating temperature and heating time are variable resistance 1
4 and 15 and timers 16 and 17, respectively. Here, by appropriately setting the resistance values of the heating resistance wires 10 and 11, the power supplies 12, 13,
It is possible to use the variable resistors 14 and 15 and the timers 16 and 17 in common. Also, heating resistance wire 1
0 and 11 may be provided on the inner peripheral surface of the container 7. Furthermore, as shown in FIG. 4, heating resistance wires 10',
11' may be provided around the heat shrink tube 6 and the optical fiber strand 5, in which case efficient and uniform heating becomes possible.

In addition, in the above-mentioned apparatus, if the primary coating 2 and buffer layer 3 of the optical fiber strand 5 to be processed are easy to remove without heating, the heating mechanism for the strand part can be omitted. .

FIG. 5 shows an embodiment in which the present invention is applied to a core wire 19 in which six optical fiber strands 5 are collectively extruded and coated with a coating 18. In this case, first, the covering 18 of the extruded core wire 19 is removed to expose the six strands 5. Next, each optical fiber strand 5 is covered with a heat-shrinkable tube 6, and the heat-shrinkable tube 6 is shrunk to cover the optical fiber strand 5 using the above-mentioned apparatus. The heat-shrinkable tube 6 does not need to cover everything other than the exposed end of the optical fiber 5, and only needs to cover the part necessary for connection or connector attachment and handling. Further, the heat-shrinkable tube 6 can also be shrunk over its entire length. By performing the terminal treatment in this manner, it is possible to handle the core extruded all at once in the same way as a conventional optical fiber core unit, and the strands can be protected.

As described above with reference to the embodiments, according to the present invention, it is possible to handle bare optical fibers in the same way as cored optical fibers, and when connecting or attaching connectors, it is possible to It becomes possible to use connecting articles and connectors for core wires.
Furthermore, since the optical fiber wire can be handled easily, the coating removal work can also be facilitated.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing the structure of an optical fiber core.
FIGS. 2a and 2b are explanatory diagrams of the procedure for terminal processing of optical fiber strands, FIG. 3 is a schematic diagram of one embodiment of the terminal processing apparatus for optical fiber strands according to the present invention, and FIG. 4 is an illustration of another embodiment. A schematic diagram of an example, FIG. 5 is an explanatory diagram when the present invention is applied to a core wire extruded all at once. In the drawings, 1 is an optical fiber, 2 is a primary coating, 3 is a buffer layer, 4 is a secondary coating, 5 is an optical fiber wire, and 6
is a heat shrink tube, 7 is a container, 9 is a stopper,
10 and 11 are heating resistance wires.

Claims (1)

[Claims] 1. A container for positioning the end of an optical fiber formed by coating an optical fiber with a primary coating and a buffer layer; a stopper for positioning a heat shrink tube at a position an appropriate amount away from the end of the optical fiber; 1. A terminal processing device for optical fiber, characterized in that it is connected to a heating means for heating a heat-shrinkable tube.