JPH078812U - Optical fiber wire and water immersion detection cable using the same - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an optical fiber wire and a water detection cable that have uniform water detection characteristics along the longitudinal direction of an object to be measured. [Structure] In an optical fiber wire 5, an optical fiber 1 and a moisture absorbing and heat generating material 2 are arranged in parallel, and are covered with a covering material 3, for example, PVC in a fixed interval relationship. Any material may be used as the inclusion. The coating 3 has a structure in which a slit 4 reaching the moisture absorbing and heat generating material 2 is provided. Further, the optical fiber wire 5 is housed in the spacer groove 10 of the optical fiber housing core 8 having the tensile strength wire 7 at the center and covered with the plastic coating 11 to form the communication cable 12.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an optical fiber wire having a function of detecting water immersion and a water immersion detection cable using the same.

[0002]

[Prior art]

 An example of the prior art is shown in FIG. In the spacer type optical fiber communication cable 12 in which the optical fiber tape 9 is housed in the spacer groove 10 of the optical fiber housing core 8 having the tensile strength wire 7 in the center and covered by the plastic coating 11 of the communication cable, one of the spacer grooves 10 is provided. A distributed type optical fiber temperature sensor line 13 and a moisture absorbing and heat generating wire 14 are disposed in the.

When the coating 11 of the communication cable 12 is broken and water enters the optical fiber core 8, the hygroscopic exothermic chemical substance accommodated in a part of the spacer groove 10 absorbs heat at the water infiltration location to generate heat. By measuring this heat with the optical fiber temperature sensor line 13 in the same spacer, it is possible to detect the flooded portion.

[0004]

[Problems to be solved by the device]

 In the prior art, since the optical fiber temperature sensor line 13 and the hygroscopic heat generating wire 14 are freely arranged in the spacer groove 10, there is a gap between them. Therefore, even if the heat-absorbing chemical substance absorbs heat during flooding and generates heat, there is a portion where the heat is not transmitted to the optical fiber temperature sensor line 13, and the heat is evenly distributed along the longitudinal direction of the optical fiber temperature sensor line 13. It was difficult to measure temperature with high sensitivity, and it was sometimes difficult to detect inundation.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide an optical fiber wire and a water detection cable that have uniform water detection characteristics along the longitudinal direction of the object to be measured.

[0006]

[Means for Solving the Problems]

 The gist of the present invention is to arrange an optical fiber and a moisture absorbing and heat generating material side by side at regular intervals, and collectively apply a coating material to the outside thereof, and a slit is provided in the coating layer to reach the moisture absorbing and heat generating material. The outer circumference of the optical fiber is covered with a heat-absorbing heat-absorbing material, the outer circumference of the metal pipe containing the optical fiber is covered with a heat-absorbing heat-absorbing material. It is stored in one or more spacer grooves.

[0007]

【Example】

 (Embodiment 1) FIG. 1 shows an embodiment of the present invention.

In FIG. 1 (A), the optical fiber wire 5 has an optical fiber 1 and a moisture absorbing / heat generating material 2 arranged in parallel, and is covered with a covering material 3, for example, PVC at a constant interval. In order to maintain a constant interval, not only PVC but also any one may be used as an inclusion. The coating 3 has a structure in which a slit 4 reaching the moisture absorbing and heat generating material 2 is provided. In the present proposal, the hygroscopic exothermic material 2 is a material formed by mixing a chemical substance (for example, calcium carbide) that causes an exothermic chemical reaction by absorbing water and a rubber-based polymer into a linear or string-like shape. .

According to this structure, since the optical fiber 1 and the moisture absorbing heat generating material 2 are kept at a constant distance over the entire length, when the absorbing heat generating chemical substance generates heat by flooding, the heat is generated by the optical fiber. 1 is even along the longitudinal direction.

Example 2 As another example, as shown in FIG. 1 (B), the outer periphery of an optical fiber 1 is coated with a moisture absorbing heat generating material 2, and as shown in FIG. 1 (C), an optical fiber is used. The optical fiber wire 5 may be formed by coating the outer circumference of a metal pipe 6 containing 1 therein with a moisture absorbing heat generating material 2.

Third Embodiment Further, the optical fiber wire 5 applied to the spacer type optical fiber communication cable 12 is shown in FIG. 2, and the spacer groove of the optical fiber accommodating core 8 having the tensile strength wire 7 at the center is shown. 1 is a communication cable 12 in which an optical fiber wire 5 as shown in FIG. 1, (A), (B) or (C) is housed in one of the members 10 and covered with a plastic coating 11.

[0012]

[Effect of device]

 As described above, according to the configuration of the present invention, it is possible to realize an optical fiber wire rod capable of detecting water intrusion in the longitudinal direction with uniform sensitivity during water infiltration and a water intrusion detection cable using the same.

[Brief description of drawings]

FIG. 1 is a perspective view (A) showing an embodiment of an optical fiber wire according to the present invention and sectional views (B) and (C) showing another embodiment.

FIG. 2 is a sectional view showing an embodiment of a spacer type optical fiber immersion detection cable using the optical fiber wire of the present invention.

FIG. 3 is a cross-sectional view of a conventional spacer type optical fiber water immersion detection cable.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical fiber 2 Hygroscopic heat generating material 3 Coating material 4 Slit 5 Optical fiber wire material 6 Metal pipe 7 Tensile strength wire 8 Optical fiber accommodating core 9 Optical fiber tape 10 Spacer 11 Plastic coating 12 Spacer type optical fiber communication cable 13 Optical fiber temperature sensor Line 14 Hygroscopic exothermic wire

Claims (4)

[Scope of utility model registration request] 1. An optical fiber and a moisture absorbing and heat generating material are arranged side by side at regular intervals, a coating material is collectively applied to the outside thereof, and a slit reaching the moisture absorbing and heat generating material is provided in the coating layer. Optical fiber wire rod characterized by. 2. An optical fiber wire rod, wherein the outer circumference of the optical fiber is coated with a moisture absorbing and heat generating material. 3. An optical fiber wire rod characterized in that the outer circumference of a metal pipe having an optical fiber therein is coated with a moisture absorbing and heat generating material. 4. A water immersion detection cable, characterized in that the optical fiber wire according to any one of claims 1 to 3 is housed in one or more spacer grooves of a spacer type optical fiber cable.