JPH0786572B2 - Optical fiber cable empty line identification method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for identifying an empty line of an optical fiber cable.

[Conventional technology]

Conventionally, in an optical fiber cable, as a method of identifying an optical fiber that has not yet been used as a communication path--that is, an empty line--, for example, the outer layer sheath of each optical fiber is colored with a different color, and each is The method of finding the empty line by distinguishing the color of the optical fiber was taken.

[Problems to be Solved by the Invention]

Normally, when identifying the empty line of an optical fiber, it must be done in a place with insufficient lighting in a manhole or a cave, and it is difficult to distinguish the color of each optical fiber. There was a risk of cutting the optical fiber of the communication path being used.

Therefore, an object of the present invention is to provide a method for identifying an empty line of an optical fiber cable, which can easily and surely select an empty line.

[Means for Solving the Problems]

In order to achieve the above object, one method of identifying an empty line of an optical fiber cable according to the present invention is an optical fiber having an optical fiber core and a plurality of the optical fibers in a plurality of concave grooves provided on an outer peripheral surface. A method for identifying an empty line in an optical fiber of an optical fiber cable including a spacer into which each fiber is fitted and a sheath covering the spacer, and peeling the sheath at a predetermined portion. After that, from the one end surface of the optical fiber which is an empty line, a visible ray for identification different from the signal light beam used for the other optical fiber which is a used line is made incident and exposed at the above-mentioned predetermined portion. By sequentially pressing only the outermost optical fiber in the concave groove, a part of the outermost optical fiber is sequentially formed with an identification portion through which visible light propagating in the optical fiber is radiated outward. , The identification unit Is intended to identify an empty line in the predetermined portion al of emitted light is determined whether identification visible light.

Further, another optical fiber cable vacant line identification method according to the present invention is an optical fiber having an optical fiber core wire, and a spacer into which the optical fiber is fitted in a plurality of grooves provided on the outer peripheral surface, respectively. A method for identifying an empty line in the optical fiber of an optical fiber cable including a sheath covering the spacer, the optical fiber being an empty line after the sheath is peeled off at a predetermined portion. While the measurement light beam is incident from one end face of the sensor, the grip portion of the sensor is grasped, and each optical fiber exposed at the predetermined portion is sequentially pressed by the pressing element of the sensor and propagated in each optical fiber. Various types of light rays are formed to form an identification portion that is emitted outward. Therefore, the emission light rays from the identification portion are made to enter the sensor from the presser, and the emission light ray is measured by the sensor. Or By cross is to identify an empty line in the predetermined portion.

[Work]

If a part of the optical fiber is pressed and deformed, the outer layer of the optical fiber is usually made semi-transparent because the thickness dimension is small.
The light beam propagating in the core of the optical fiber core wire is emitted from the deformed portion to the outside through the outer layer.

Therefore, in the optical fiber cable, after the sheath is peeled off at a predetermined portion, visible light for identification is made incident from one end face of the empty line, and only the outermost optical fiber in the concave groove exposed at the predetermined portion is sequentially arranged. When pressed, visible light propagating in the optical fiber is emitted outward from the identifying portion. From this, if the emitted light ray is a visible ray for identification, it can be seen that the deformed optical fiber is an empty line.

In addition, after peeling off the sheath at a predetermined site,
While irradiating from one end face of the empty line, grasp the grip portion of the sensor and press the exposed optical fiber at the predetermined portion with the pressing element of the sensor in order, and the light beam propagated through the optical fiber is identified by the identification portion. Light enters the sensor through the presser. If the incident light is a measuring light beam, the sensor reacts and informs that it is a measuring light beam, and it can be seen that the optical fiber pressed is an empty line.

〔Example〕

 Hereinafter, embodiments will be described with reference to the drawings.

FIG. 1 and FIG. 2 show an optical fiber cable used in the air line identification method according to the present invention. This cable includes an optical fiber 2 having an optical fiber core wire 1 and a plurality of optical fibers provided on an outer peripheral surface 3. Spacers 5 into which the optical fibers 2 are fitted in the recessed grooves 4, and a sheath 6 that covers the spacers 5,
Is equipped with. Further, a tension member 7 (steel wire or the like) is installed in the axial center portion of the spacer 5.

Here, the recessed grooves 4 ... Of the spacer 5 are spirally provided along the longitudinal direction, and the recessed grooves 4 ...
Five optical fibers 2 are inserted for each. Further, the optical fiber core wire 1 is, as shown in FIG.
And a clad 9 for covering the core 8 and a cover layer 10 for covering the clad 9, and the five core wires 1 ... The optical fiber 2 is formed by coating. That is, the optical fiber 2 in this case is of a so-called tape type. Further, as the coating layer 10 and the exterior layer 11, a highly transparent material is used, or the exterior layer 11 is made of a highly transparent material and at least one coating layer 10 of the optical fiber core wire 1 is colored. Do not apply.

Then, if the optical fiber 2 is curved or pressed and deformed, the light rays propagating in the optical fiber core wire 1 of the optical fiber 2 will be curved as indicated by the broken line arrow in FIG. It is radiated outward from the shape portion (that is, the identification portion 12). That is, the light beam propagating in the core 8 exceeds the critical angle of total reflection when entering the clad 9 in the identification portion 12, and this light beam is emitted from the clad 9, the covering layer 10, and the exterior layer 11.
It passes through and is emitted to the outside.

Then, when branching the optical fiber 2 (empty line),
As shown in FIG. 1, the sheath 6 is peeled off at two places to form the exposed portions 13 and 14 of the optical fiber core wire 1, and the empty line is cut at one exposed portion 13 and the other exposed portion is cut. 14
Pull out as shown by the virtual line. The optical fibers 2 to be extracted are all the five optical fibers 2 ... This is because, in this case, all the five optical fibers 2 ... In one concave groove 4 are empty lines.

Therefore, it is necessary to identify an empty line in one exposed portion 13 (that is, the predetermined portion 15). Therefore, the empty line is identified by the identification method of the present invention. In this case, a visible ray is a ray propagating in the optical fibers 2.

Then, from one end face of the optical fiber 2 ...
While injecting visible light for identification as shown by arrow A,
In 15, only the outermost optical fiber 2 in each groove 4,
Are sequentially pressed as indicated by arrow B to be deformed by pressing. Therefore,
When it is pressed and deformed, as shown in FIG. 4, the pressed and deformed portion serves as the identification portion 12 from which the light beam propagating in the optical fiber 2 is radiated outward. As a signal light beam different from the signal light beam used in another optical fiber 2 which is a used line, it is judged whether or not this emitted light beam is a visible ray for identification, and an empty line in a predetermined portion 15 is identified. . That is, if only the outermost optical fiber 2 in each concave groove 4 is sequentially pressed to form the identification portion 12, if it is not a vacant line, signal rays other than the identification signal ray will be emitted, and the manhole will be emitted. Workers can immediately determine that the line is not empty even if the lighting in the area is insufficient, and
If the optical fiber 2 on which the identifying section 12 is formed is a vacant line, since it emits visible light for identification, it can be immediately determined that the optical fiber 2 is a vacant line.

By the way, as an identification method, visible light for identification may be incident on all the optical fibers 2 in one groove 4 to identify whether or not there is a vacant line, but in general, in one groove 4 Since all the optical fibers 2 (in this case, 5) are empty circuits, only the outermost optical fibers 2 need be identified.

Next, FIG. 5 shows a sensor 16 used in another embodiment. The sensor 16 detects only the measuring light beam in a certain wavelength range.

Then, this sensor 16 has a pressing member 17 made of a transparent material,
The sensor main body 18 and the grip portion 19 are provided, and the grip portion 19 is gripped, the optical fiber 2 is pressed as shown by the arrow in FIG. 5I, and the discriminating portion as shown in FIG. 12 is formed, and a radiant ray is incident from the pressing element 17. An elastic member 20 such as a coil spring is interposed in the grip portion 19 to regulate the pressing force of the pressing element 17 on the optical fiber 2. That is, the pressing force of the pressing element 17 is made to be the elastic force of the elastic member 20 while the stroke of the pressing element 17 is constant. The stroke means the state shown in FIG.
As shown in II, it refers to the dimension until the upper end edge 18a of the sensor body 18 comes into contact with the upper end surface 22 of the recess 21 of the grip portion 19.

Here, it is desirable that the measuring light beam has a constant frequency that is modulated. That is, since the sensor 16 for detecting a light ray detects a light ray having a wavelength within a certain range, modulation is applied to prevent detection of a light ray other than the light ray to be detected. If only the one with a constant frequency is detected, no light rays other than the measurement light ray that is desired to be detected are detected. Therefore, this measurement light beam may be visible light or other than visible light.

Therefore, in order to identify a vacant line using this sensor 16, as shown in FIG.
After exposing each optical fiber 2 ..., While pressing the measurement light beam from one end face of the air line, the pressing element 17 is pressed against each optical fiber 2 ... As shown in FIG. That is, if the pressed optical fiber 2 is an empty line, a measuring light beam is emitted from the identification unit 12, and the sensor 16 detects it and notifies the worker that it is an empty line. If the optical fiber 2 is not an empty line but an already used line, the sensor 16 does not respond to the emitted light and informs the operator that the optical fiber 2 is not an empty line. As a method of informing the worker from the sensor 16, the sensor 16 itself may be made to emit light, or an alarm device or the like may be connected to the sensor 16.

The optical fiber cable used in the present invention is not limited to that of the embodiment, and for example, the optical fiber 2
Can be freely formed into a round shape (that is, the optical fiber core wire 1 is arranged along the circumferential direction), and each groove 4 is free.
The number of optical fibers 2 to be fitted inside is also free,
Further, the number of the optical fiber core wires 1 is not limited to five. Further, it is also preferable that the single optical fiber 1 is used as the optical fiber 2. Also, the number of the concave grooves 4 is of course free, and the twist angle is also free.

〔The invention's effect〕

Since the present invention is the method as described above, it has the following effects.

In the method of identifying a vacant line of an optical fiber cable according to claim 1, if the identification portions 12 are sequentially formed on the outermost optical fibers 2 exposed at a predetermined portion 15, visible light rays are emitted from the identification portions 12 to the outside. If the emitted light is a visible ray for identification, it is immediately known that the optical fiber 2 is a vacant line, and even if it is in a manhole where illumination is insufficient. The color of the visible light for identification can be identified, and the empty line can be identified easily and reliably.

According to the optical fiber cable empty line identification method of claim 2, each optical fiber 2 exposed at the predetermined portion 15 is exposed.
... by grasping the grip portion 19 of the sensor 16 in sequence
When pressing with the pressing element 17 of 16, the radiant ray enters the sensor 16 from the identification section 12, and if the radiant ray is a measuring ray, the sensor 16 reacts and the fiber 2 immediately
Is a free line and has excellent workability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial cross-sectional side view of an optical fiber cable used in an empty line identifying method according to the present invention, FIG. 2 is an enlarged sectional view of the same, and FIG. 3 is an enlarged sectional view of an optical fiber. 4 and 5 are cross-sectional views of the optical fiber in the state where the identification portion is formed, and FIG. 5 is a partial cross-sectional front view for explaining the method of using the sensor. 1 ... Optical fiber core wire, 2 ... Optical fiber, 3 ... Outer peripheral surface, 4 ... Groove, 5 ... Spacer, 6 ... Sheath, 12 ...
… Identification part, 15 …… predetermined part, 16 …… sensor.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Haruki Kitagawa, 3-3 Ikejiri, Itami City, Itami City, Hyogo Prefecture Mitsubishi Cable Industries, Ltd., Itami Works (72) Inventor, Satoru Shinomiya 4-chome, Ikejiri, Itami City, Hyogo Prefecture Mitsubishi Cable Industries, Ltd. Itami Manufacturing Co., Ltd.

Claims (2)

[Claims] 1. An optical fiber having an optical fiber core wire, a spacer into which a plurality of optical fibers are respectively fitted in a plurality of concave grooves provided on an outer peripheral surface, and a sheath which covers the spacer. A method for identifying a vacant line of the optical fiber of an optical fiber cable, which is a used circuit from one end face of the vacant optical fiber after the sheath is peeled off at a predetermined portion. Visible light for identification different from the signal light beam used in other optical fibers is made incident, while sequentially pressing only the outermost optical fiber in the concave groove exposed at the predetermined portion, A part of the optical fiber is sequentially formed with an identification part in which the visible light propagating in the optical fiber is radiated outward, and thus it is determined whether or not the emitted light from the identification part is an identification visible light. Empty space An empty line identification method for an optical fiber cable that identifies the line. 2. An optical fiber having an optical fiber having an optical fiber core, a spacer into which the optical fiber is fitted in a plurality of recessed grooves provided on an outer peripheral surface, and a sheath covering the spacer. A method for identifying a vacant line in the optical fiber of a cable, in which a sheath is peeled off at a predetermined portion, and then a measuring light beam is made incident from one end face of the optical fiber which is a vacant line, Grasp the grip of the sensor and press the optical fibers exposed at the predetermined portion with the pressing element of the sensor in order to sequentially identify various light rays propagating in the optical fibers to the outside. And thus the emitted light from the identification part,
A method for identifying an empty line of an optical fiber cable, in which a light is incident on a sensor from the presser, and the sensor determines whether the emitted light is the measurement light to identify an empty line at the predetermined portion.