JPH04215605A - Optical cable terminal and optical cable connection - Google Patents

Abstract

PURPOSE:To easily handle a surplus of the length or an optical fiber, and easily perform drawing-out of the optical fiber from the a surplus length handling unit. CONSTITUTION:The outer periphery of an optical fiber drawn out from the end part of an optical cable 1 with a surplus length is covered by a spiral plastics 16.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical cable terminal section and an optical cable connection section.

0002

[Prior art] In order to improve the workability of connections on site,
As shown in FIG. 4, an optical cable has been proposed in which a connector 3 is attached in advance to each optical fiber 2 led out from the terminal of a cable 1. In addition, 4 is optical cable 1
This is a sheath retaining part provided at the end of the cable sheath 5.

[0003] In such an optical cable with a connector,
In order to protect each connector 3 and each optical fiber 2 during drum winding, storage, and installation, a flexible protective tube 6 is placed at the tip of the cable sheath 5 in a liquid-tight manner to cover each optical fiber 2 with a connector, as shown in the figure. installed. The flexible protection tube 6
The outer diameter of the tube is set to a size that allows it to pass through the pipe. Inside the flexible protective cylinder 6, reinforcing disks 7 are arranged intermittently in the longitudinal direction in order to maintain the ironing strength. A pulling eye 8 is attached to the tip of the flexible protection tube 6. A connector accommodating disk 9 is further provided inside the flexible protection tube 6, and the connector accommodating disk 9 has a connector accommodating hole 1.
0 is provided for each. The connectors 3 are inserted and housed in the connector housing holes 10, respectively. The positions of the connectors 3 are shifted in the longitudinal direction so that the outer diameter of the flexible protection tube 6 does not increase due to overlapping positions.

[0004] In this case, the optical fibers 2 within the flexible protection tube 6 may have the same protrusion length from the cable sheath 5. In such a case, the optical fiber 2 attached to the connector 3 on the side closer to the cable sheath 5 has an extra length, so the extra length is processed. Conventionally, the surplus length of the optical fiber 2 has been processed by storing the surplus length of the cut optical fiber 2 in a sheet or in a tray.

[0005] After the optical cable terminal part having the structure shown in FIG. 4 is installed in a conduit, the optical fibers 2 of each cable 1 are connected with a connector 3 in a manhole or the like to form a fiber connection part 11. It is housed in a closure 1 as shown in FIG. 5, and becomes an optical cable connection section 13. Note that the closure sleeve is omitted in this figure, and the end plate 14 that closes both ends of the closure sleeve is shown. At this time, an extra length is generated in the optical fiber 2, so it is necessary to process the extra length. Conventionally, when processing the extra length of the optical fiber 2, the extra length of the optical fiber 2 that has been looped is processed as shown in FIGS.
This has been done by storing it in a sheet 15 shown in FIG. 1 or in a tray (not shown).

[0006]

However, such conventional optical cable terminal sections and optical cable connection sections have a problem in that processing the excess length of the optical fiber 2 requires considerable effort and time. Furthermore, in the conventional method, the optical fiber 2 which has been looped in order to process the excess length is stored in a sheet 15, a tray, etc., so there is a problem in that it takes time and effort to pull out the optical fiber 2 when necessary.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical cable terminal section and an optical cable connection section that can easily process the excess length of an optical fiber and easily draw out the optical fiber from the excess length processing section. It's about doing.

[0008]

[Means for Solving the Problems] The structure of the present invention for achieving the above object will be explained as follows.

The optical cable terminal section according to the first aspect is characterized in that the outer periphery of the optical fiber led out with an extra length from the end of the optical cable is covered with a helical plastic tube.

[0010] In the optical cable connection section according to the second aspect of the present invention, a spiral plastic tube is placed over the outer periphery of each optical fiber led out with an extra length from the ends of both optical cables to be connected. It is characterized in that the tips of the optical cables are connected to each other.

[0011]

In the structure of claim 1, a helical plastic tube is placed over the outer periphery of the optical fiber to form a helical extra length processing section. In such a spiral extra length processing section, since the spiral plastic tube also serves as a protector, there is no need to store it in a sheet, a tray, or the like.

In the structure of the second aspect, a spiral plastic tube is placed over the outer periphery of both optical fibers to be connected to form a spiral surplus length processing section. In the present invention, the processing of the extra length of each optical fiber is completed in this state, and there is no need to accommodate it in a sheet, tray, or the like. Further, in this helical extra length processing section, the required optical fiber length is supplied by extending the helical portion.

[0013]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIGS. 1 and 2 show an example of the optical cable terminal section of this embodiment.

In this embodiment, the optical fiber 2 led out from the end of the optical cable 1 with an extra length is passed through a helical plastic tube 16. This allows the optical fiber 2
has a helical shape to match the shape of the helical plastic tube 16. In this state, the optical fiber 2 completes its extra length processing and becomes a spiral extra length processing section 17.

The helical plastic tube 16 is made by bending a tube made of, for example, nylon, polypropylene, polyvinyl chloride, polyethylene, etc. into a helical shape with a bending radius greater than or equal to the allowable bending radius (R about 30 mm) of the optical fiber 2 (for example, 60 mmφ). Form by doing.

A connector 3 is connected to the tip of the optical fiber 2 led out from the tip of the helical plastic tube 16, and the connector 3 and the helical plastic tube 1 are connected to each other.
6, and the helical plastic tube 16 and optical cable core 18 are fixed with fixtures 19 and 20.

The spiral extra length processing section 17 is housed in the flexible protection tube 6, and the connector 3 is inserted into the connector accommodation hole 10 of the connector accommodation disk 9 provided in the flexible protection tube 6. to fit in. At this time, the spiral extra length processing section 17 is expanded or contracted depending on the position of the connector housing disk 9 in the longitudinal direction of the flexible protection tube 6.

[0019] Thus, an optical cable terminal portion as shown in FIG. 2 is completed. Spiral extra length processing section 1 inside flexible protection tube 6
7, since the spiral plastic tube 16 itself also serves as a protector for the optical fiber 2, there is no need to store it in a sheet or tray.

FIG. 3 shows an example of the optical cable connection section 13 formed using the optical cable terminal section shown in FIG. In the optical cable connection section 13, the connectors 3 at the tips of both spiral extra length processing sections 17 are connected to each other within the closure 12 to form a fiber connection section 11,
The fiber connection section 11 is supported by a connection section support 21 .

[0021] Since the spiral plastic tube 16 itself also serves as a protector for the optical fiber 2, the spiral surplus length processing section 17 in the closure 12 of the optical cable connection section 13 can be stored in a sheet, a tray, etc. There's no need to.

[0022] The fiber connection section 11 is connected to the optical fiber 2.
They may be fused together.

[0023]

[Effects of the Invention] As explained above, according to the optical cable terminal section and the optical cable connection section according to the present invention, the following effects can be obtained.

In the optical cable terminal section and optical cable connection section according to claims 1 and 2, the optical fiber led out from the terminal section of the optical cable with an extra length is coated with a helical plastic tube to form a spiral extra length. Since a processing section is formed, there is no need to store it in a sheet, tray, etc. In this helical extra length processing section, the optical fiber is formed into a helical shape by the helical plastic tube, so when the optical fiber is looped as in the conventional method, the optical fiber bounces due to its elasticity and the loop is broken. This makes it easier to process excess length. In addition, in this helical extra length processing section, the helical plastic tube maintains its spiral shape, so when the looped portion of the optical fiber is taken out from a sheet etc. as in the past, the looped shape is broken and it becomes straight. This makes handling easier. Moreover,
When tension is applied to this helical extra length processing section, the helical pitch increases and it expands, and conversely, it is also possible to shorten it to a small helical pitch. This has the advantage that optical fibers can be freely supplied.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a state of an embodiment of an optical cable terminal section according to the present invention before a protection tube is attached.

FIG. 2 is a longitudinal cross-sectional view of an embodiment of an optical cable terminal section according to the present invention.

FIG. 3 is a longitudinal cross-sectional view of an embodiment of the optical cable connection part according to the present invention.

FIG. 4 is a vertical cross-sectional view of a conventional optical cable terminal section.

FIG. 5 is a perspective view of a conventional optical cable connection section with a closure sleeve omitted.

FIG. 6 is a front view of a conventional extra length processing section.

[Explanation of symbols]

1 Optical cable 2 Optical fiber 3 Connector 4 Sheath retaining part 5
Cable sheath 6 Flexible protection tube 8 Pulling eye 9
Connector housing disk 10 Connector housing hole 11 Fiber connection section 12 Closure 13 Optical cable connection section 14
End plate 15 Sheet 16 Helical plastic tube 17
Spiral extra length processing section 19, 20 Fixture

Claims (2)

[Claims] 1. An optical cable terminal section, characterized in that the outer periphery of an optical fiber led out with an extra length from the end of the optical cable is coated with a spiral plastic tube. [Claim 2] A helical plastic tube is placed over the outer periphery of each optical fiber led out with an extra length from the ends of both optical cables to be connected, and the distal ends of both optical cables are connected to each other. An optical cable connection section characterized by: