JPH0590339U - Leak detection cable - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a water leakage detection cable capable of reliably detecting the water leakage of a liquid having a large insulation resistance. [Structure] The water leakage detection cable 1 is composed of a pair of conductor electrodes (round wire conductors) 2 made of stainless steel or the like arranged in parallel in the longitudinal direction and made of fibers of an insulating member. ) Is impregnated into the braid 11 and the detection lines 12 and 12 formed in parallel are arranged in parallel, and the water leakage detection unit 6 and the conductor 3 are provided.
3 is provided with a return line portion 8 composed of core wires 5 and 5 with insulating coatings 4 and 4, and an insulating tape 9 composed of an insulating layer 9A and an adhesive layer 9B is provided on the lower surface of the return line portion 8 and an adhesive layer 9B. The upper surface of the leak detection unit 6 and the return line unit 8 with insulation, and the holes 7A, 7A are randomly formed on the entire surface.
Arrange the water-permeable insulating tape 7 provided with (punching),
The water leak detection unit 6 and the return line unit 8 are joined to and integrated with the insulating tape 9.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to improvement of a water leak detection cable.

[0002]

[Prior Art]

 In recent years, office automation has advanced and many intelligent buildings have been constructed. As a result, computers and various electrical equipment will be installed in the building, and in order to protect each of these electrical equipment from damage caused by dew condensation and water leakage in the building, a water detector is placed around the electrical equipment. Therefore, it is an essential requirement to minimize the damage caused by water leakage. The applicant of the present invention has previously developed a "leakage detection system" capable of detecting water leakage and specifying the location of water leakage (Japanese Patent Application No. 1-142550). This water leak detection system is realized by arranging a pair of water leak detection lines and a pair of return lines horizontally in the longitudinal direction and using an integrated water leak detection cable.

A water leak detection cable 20 shown in FIGS. 4 to 6 is a water leak detection unit composed of a pair of conductor electrodes (circular wire conductors) 2 formed of stainless steel or the like arranged in parallel in the longitudinal direction. 6 and a return line portion 8 composed of a pair of core wires 5 and 5 in which insulating coatings 4 and 4 are applied to the conductors 3 and 3 arranged in parallel with the conductor electrodes 2 and 2, and the lower surfaces of these are provided. An insulating tape 9 composed of an insulating layer 9A and an adhesive layer 9B is arranged with the adhesive layer 9B facing upward, and the upper surfaces of the water leak detection unit 6 and the return line unit 8 are insulative and are randomly formed over the entire surface. A water-permeable insulating tape 7 provided with holes 7A, 7A (punched) is arranged on the insulating tape 9 and the leak detection unit 6 and the return line unit 8 are joined to the insulating tape 9 to be integrated. There is.

The conductor electrodes 2, 2, 3 and 3 are 28 AWG size (cross-sectional area 0.093 [mm ² ], 7 / 0.13 [mm] single wires 2 a, 2 a or conductors 3 a, 3 a It has a structure in which the pitch is 6 [mm] or less.

The insulating coatings 4 and 4 have a coating thickness of 0.15 [mm] using heat resistant PVC, ETFE, and FEP in consideration of heat resistance and flexibility. The water-permeable insulating tape 7 is composed of polyester tape (plastic tape). The water leak detection cable 20 configured as described above has a pair of conductor electrodes that are in an insulated state when a drop of an aqueous solution (including an aqueous solution of water, acid, alkali, etc.) is placed on the upper surface of the water-permeable insulating tape 7. 2 and 2 will be short-circuited via the aqueous solution, and a detector (not shown) provided at the end of the conductor electrodes 2 and 2 will detect a change in the insulation resistance value between the conductor electrodes 2 and 2. By doing so, the occurrence of water leakage is detected.

[0006]

[Problems to be solved]

 In the water leak detection cable 20 according to the above conventional example, when water leak occurs, the water leaks into the water leak detection unit 6 and the insulation resistance value between the conductor electrodes 2 and 2 decreases (short circuit state), so that water leak occurs. In addition to the above, the system is designed to detect the leak position. However, if the leaked water is a liquid with low insulation resistance such as tap water, it is possible to detect the leaked water. However, for example, if it is placed in a place where pure water (ultra pure water) is handled in a semiconductor manufacturing plant, Since the pure water has a large insulation resistance, even if the pure water permeates the water leak detecting portion 6, the occurrence of the water leak cannot be substantially detected.

[0007]

[The purpose of the device]

 SUMMARY OF THE INVENTION It is an object of the present invention to provide a water leakage detection cable that improves the disadvantages of the above conventional example and can reliably detect the water leakage generation of a liquid having a large insulation resistance.

[0008]

[Means for Solving the Problems]

 Therefore, in the present invention, at least one of the upper and lower insulating tapes is made of a water-permeable tape, and two cables in which conductors are coated with a water-permeable braid are arranged in parallel in the longitudinal direction between these insulating tapes. The water leakage detecting cable arranged in the first embodiment is intended to achieve the above object by adopting a structure in which the water-permeable braid is impregnated with conductive ions.

[0009]

【Example】

 An embodiment according to the present invention will be described below with reference to FIGS. 1 to 3. Here, the same components as those in the above-mentioned conventional example are designated by the same reference numerals.

The water leak detection cable 1 shown in FIG. 1 is composed of conductor electrodes (circular wire conductors) 2 formed of a pair of stainless steels arranged in parallel with the longitudinal direction and made of fibers of an insulating member. , A leak detection part 6 in which detection wires 12 and 12 covering a braid 11 impregnated with conductive ions (such as salt water) are arranged in parallel, and a core wire in which insulation coatings 4 and 4 are applied to the conductors 3 and 3. 5, a return line portion 8 composed of 5 and 5 is provided, and an insulating tape 9 composed of an insulating layer 9A and an adhesive layer 9B is arranged on the lower surface of the return line portion 8 with the adhesive layer 9B facing upward, and the water leakage detecting portion 6 And a water-permeable insulating tape 7 which is insulative and has holes 7A, 7A (punched) randomly formed on the entire surface of the return line portion 8 and the leak detection portion 6 and the return line portion 8 And the insulating tape 9 are joined and integrated.

The conductor electrodes 2, 2, 3 and 3 are of 28 AWG size (cross-sectional area 0.093 [mm ² ], 7 / 0.13 [mm] single wires 2 a, 2 a or conductors 3 a, 3 a, ... 3a is twisted with a pitch of 6 mm or less.

The insulating coatings 4 and 4 have a coating thickness of 0.15 [mm] using heat resistant PVC, ETFE, and FEP in consideration of heat resistance and flexibility. The water permeable insulating tape 7 is made of polyester tape (plastic tape). The water leakage detection cable 1 thus configured has a pair of conductor electrodes 2 that are in an insulating state even if a drop of aqueous solution, for example, ultrapure water having a large insulation resistance, is applied to the upper surface of the water-permeable insulating tape 7. , 2 is mixed with the conductive ions impregnated in the braid 11 in the aqueous solution, the electrical resistance is reduced and short-circuited, and the detector (provided at the end of the conductor electrodes 2, 2) ( The occurrence of water leakage is detected by detecting a change in the insulation resistance value between the conductor electrodes 2 and 2 (not shown).

Since the present embodiment is configured as described above, it is possible to provide a water leak detection cable capable of reliably making a water leak detection judgment even for water leak of a liquid material having a large insulation resistance.

In this embodiment, the water leak detection unit 6 and the return line unit 8 are round wire conductors, but they may be rectangular wires, and the water leak detection unit 6 and the return line unit 8 may have different shapes. The water-permeable insulating tape 7 or a non-woven fabric having a similar function may be arranged on both sides. Furthermore, the return line portion 8 may be provided if necessary, and may not be provided particularly when the function of detecting the water leakage position is not required. On the other hand, in the case of this embodiment, the back surface may be the water-permeable insulating tape 7, or the adhesive tape may be formed with holes 7A, 7A (punched) in a random pattern over the entire surface.

Further, the holes 7A of the water-permeable insulating tape 7 are not limited to a circular shape, but may be a rectangular shape.

[0016]

[Effect of the device]

 Since the present invention is configured as described above, it is possible to provide a water leak detection cable that can reliably detect the occurrence of water leak of a liquid having a large insulation resistance.

[Brief description of drawings]

FIG. 1 is an explanatory view of an assembling process of a water leak detection cable according to an embodiment of the present invention.

FIG. 2 is a perspective view of the water leak detection cable shown in FIG.

FIG. 3 is a cross-sectional configuration diagram of a water leakage detection cable according to this embodiment.

FIG. 4 is an explanatory view of an assembling process of a water leakage detection cable according to a conventional example.

5 is a perspective view of the water leak detection cable shown in FIG.

FIG. 6 is a cross-sectional configuration diagram of a water leakage detection cable according to a conventional example.

[Explanation of symbols]

 1 …………… Leakage detection cable 2 ……………… Conductor electrode 3 ……………… Conductor 5 ……………… Core wire 6 …………… Leakage detection part 7 …………… Water-permeable insulation Tape 8 ……………… Return line part 9 ……………… Insulating tape 11 ………… Braid 12 ………… Detection line 7A ………… Hole

Claims (1)

[Scope of utility model registration request] 1. At least one of the upper and lower insulating tapes is a water-permeable tape, and between these insulating tapes, two cables having conductors covered with a water-permeable braid are arranged in parallel in the longitudinal direction. It is a leak detection cable that I arranged,
A water leakage detection cable, wherein the water-permeable braid is impregnated with conductive ions.