JPH1019818A - Conductive forein matter detecting sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect permeating moisture in bank soils and estimate bank rips etc. SOLUTION: An electrode part 6 comprising a comb-like electrode 4 and a comb-like cathode electrode 5 counter to each other is connected to between a first conductive cable 2 and a second conductive cable 3, to structure a permeating moisture detecting sensor 1. When moisture permeates the electrode part 6, the electrodes 4, 5 are shortcircuited to each other to form a closed loop, which is detected by an external output detection part. Thereby, moisture in bank soils is detected by the permeating moisture detecting sensor, and a collapse of precipices, a rip of banks, etc., are forecast by estimating ground strength, and a system configuration for preventing beforehand secondary disaster is possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive foreign matter detection sensor for detecting a conductive foreign matter, and more particularly, to the amount of water in soil or embankment as a conductive foreign matter, which causes collapse of a cliff or break of a dike. The present invention relates to a conductive foreign matter detection sensor capable of detecting an object.

[0002]

2. Description of the Related Art As a conventional sensor for detecting a liquid, a sensor using an optical fiber itself as a sensor is known. This sensor uses the fact that the optical refractive index of the optical fiber changes when the liquid comes into contact with the surface of the optical fiber, and detects leakage of the liquid based on the amount of light transmitted through the optical fiber.

Further, there is known a sensor which detects a liquid leakage by applying a characteristic that a dielectric constant changes when a liquid comes into contact with a conductor and evaluates a change in a characteristic impedance of a cable. This sensor has a structure of a liquid-permeable coaxial cable in which an insulating material between an outer braid and a core wire is made of porous Teflon that is easily permeable to liquid and water-resistant.

[0004] These two types of liquid detection sensors are described, for example, in "Measurement and Control" vol. 25, NO. No. 10 (October 1986) is known. However, these sensors limit the target liquid to petroleum,
These sensors cannot detect many types of liquids including water.

[0005]

In the above prior art, a liquid detection sensor having an optical fiber or a liquid permeable coaxial cable structure is installed in parallel with an oil plant pipeline.
It is intended to detect an oil leak from a pipeline, and there is a problem that it is difficult to confirm the presence or absence of various liquids penetrating into soil.

SUMMARY OF THE INVENTION It is an object of the present invention to detect conductive foreign substances in an object, confirm the presence or absence of various liquids penetrating into soil, embankments, and the like, and evaluate the fragility of the ground, It is an object of the present invention to provide a conductive foreign matter detection sensor that can monitor a break and can be widely used.

[0007]

In order to achieve the above object, a conductive foreign matter detection sensor according to the present invention comprises a first conductive cable, a second conductive cable, a first conductive cable and a second conductive cable. And an electrode portion composed of opposing comb-shaped electrodes connected between the cables, and detects a conductive foreign substance in the electrode portion from an amount of current when a constant voltage is applied between the first and second conductive cables. .

Further, a plurality of electrode portions are connected between the first and second conductive cables.

Further, the conductive foreign matter detection sensor of the present invention comprises:
A first conductive cable, a second conductive cable, a third conductive cable, and opposing comb teeth connected between the first and second conductive cables and between the second and third conductive wire cables And a plurality of electrode portions each of which is formed in a shape of a conductive electrode. The conductivity of the electrode portion is determined from the amount of current when a constant voltage is applied between the first and second conductive cables and between the second and third conductive cables. Detects sexual contaminants.

[0010] The surface of the electrode portion is made of a material having excellent corrosion resistance such as gold.

Further, the conductive cable is covered with an insulating film.

The above-mentioned electrode portion is molded with a liquid-permeable insulating film.

Further, the conductive foreign matter detection sensor is buried in the soil to detect moisture in the soil as the conductive foreign matter.

Further, the conductive foreign matter detection sensor is buried in the embankment, and detects moisture in the embankment as the conductive foreign matter.

[0015]

FIG. 1 is a block diagram showing an embodiment of the present invention.
6 will be described with reference to FIG. FIG. 1 is a structural diagram showing a first embodiment of a sensor for detecting moisture permeating into a conductive foreign substance, for example, an embankment, of the present invention. In FIG. 1, a permeated moisture detection sensor 1 is disposed between a first conductive cable 2 and a second conductive cable 3 at regular intervals so as not to short-circuit a comb-shaped anode electrode 4 and a comb-shaped cathode electrode 5. This is a configuration in which the electrode portions 6 are connected. The reason why a plurality of comb teeth are formed instead of one tooth is to detect the permeated moisture not in one point in the soil but in a certain spread range.

The first and second conductive cables 2 and 3 are coated with insulation so that moisture does not enter the core wires in the table from the outside. The comb-shaped anode electrodes 4 and 5 opposed to the electrode section 6 have a configuration in which the surface (that is, the conductive surface) is exposed. The entire electrode portion 6 is inserted into the box, and a small window for water penetration is provided around the box, or a water-permeable material such as a degreasing wire is provided around the electrode 6. This allows natural moisture to penetrate into the electrode unit 6.

FIG. 2 is a diagram for explaining the function of the sensor for detecting permeated moisture in FIG. 2, the permeated moisture detecting operation of the permeated moisture detecting sensor 1 of FIG. 1 is performed by detecting the presence or absence of a short circuit between the electrodes 4 and 5 of FIG. 2, the first conductive cable 2 and the second conductive cable 2. Voltage generation unit 11 and protection resistance unit 12 connected in series between conductive cables 3 and protection resistance unit 12
And an osmotic moisture detecting system 13 configured in parallel with the osmotic moisture detecting unit 13.

When the permeated moisture is not present in the electrode portion 6 of the permeated moisture detection sensor 1, the permeated moisture detection system is in an open-loop state and generates no electric current. No output detection unit 13 generates a permeated moisture detection signal. However, for example, when the permeated moisture 14 contacts the electrode portion 6 of the permeated moisture detection sensor 1,
The circuit enters a closed loop energized state, and the osmotic moisture output detector 13 detects an osmotic moisture signal.

FIG. 3 is a structural view showing a second embodiment of the permeated moisture detecting sensor according to the present invention. In FIG. 3, a plurality of permeation moisture detection sensors 21 are provided in parallel between a first conductive cable 22 and a second conductive cable 23,
This is a configuration in which four electrode units 24 similar to those in FIG. 1 are connected in parallel.

FIG. 4A shows a detection system including the equivalent circuit of FIG. In this equivalent circuit, the electrode units 24 to 27 are connected in parallel. At the end, a voltage generator 11 (for example, a battery), a resistor 12, and an output detector 13 shown in FIG. 2 are provided. When at least one of the electrode units 24 to 27 is short-circuited (ON) due to the presence of permeated moisture, a closed loop is formed, and the output detection unit 13 detects this. Therefore, according to the detection system of FIG. 4, only one of the four electrode units 24 to 27 can be detected to be short-circuited.

FIG. 4B shows a detection system for detecting which of the four electrode portions 24-27 is short-circuited. Different resistances R are connected in series with the respective electrode portions 24 to 27.
_{1 to} R ₄ were provided. As a result, if there is one or more electrode units that are short-circuited among the electrode units 24 to 27, a current flows according to the series resistance value, and the detection unit 13 detects this. From the magnitude of the current, it is possible to know which electrode section has short-circuited, and if two or more electrode sections are short-circuited, which short-circuited electrode is which.

FIG. 4C shows a detection system in which resistors R _{1 to} R ₄ and batteries E _{1 to} E ₄ are provided in series with the electrodes 24 to 27, respectively. As in FIG. 4B, it is possible to know whether or not one or more of the electrode portions 24 to 27 are short-circuited and which short-circuit electrode portion is.

FIG. 5 is a structural view showing a third embodiment of the permeated moisture detecting sensor according to the present invention. In FIG. 5, the permeated moisture detection sensor 31 is provided between the first conductive cable 32 and the second conductive cable 33 and the second conductive cable 33.
In this configuration, a plurality of, here, four and three electrode portions 35 similar to FIG.

In the detection sensor of FIG. 5, FIG.
The detection system as described in (b) and (c) can detect the presence or absence of a short circuit in the electrode section.

FIG. 6 is a structural diagram showing a fourth embodiment of the permeated moisture detecting sensor according to the present invention. FIG. 6 shows an embodiment in which the sensor for detecting permeated moisture of the present invention is embedded in, for example, the soil to detect the presence or absence of permeation. Here, in addition to the configuration in which the electrode portion 6 is connected between the first conductive cable 2 and the second conductive cable 3 as in FIG. 1, the sensor 41 is further embedded in the soil. Since the installation conditions are poor mainly for the purpose of detecting moisture in the soil, the outside of the first conductive cable 2 and the second conductive cable 3 is further covered with an insulating film 42 for preventing corrosion, and Is covered with a liquid-permeable insulating film 43. Further, the electrode portion 6 may be placed in a box or the like as in FIG. 1 so as to allow penetration of water permeated through a small window of the box.

FIG. 7 is a perspective view showing a fifth embodiment of the permeated moisture detecting sensor according to the present invention. FIG. 7 shows an embodiment in which the sensor for detecting permeated moisture of the present invention is buried, for example, in the soil in the embankment 52 and detects the presence or absence of moisture permeation into the embankment. Here, the permeated moisture detection sensor 51 has the same configuration as the permeated moisture detection sensor 41 of FIG. 6, and this detection sensor 51 is embedded in the embankment 52.

The detecting operation of the permeated moisture detecting sensor 51 is similar to that shown in FIG. 2 except that the voltage generating section 53 and the protection resistor section are connected in series between the first conductive cable 2 and the second conductive cable 3. This is performed by a levee waterproofing detection system composed of a protection resistor 54 and an output detector 55 connected in parallel.

Further, there are the following modes. (1) If the electrode surface of the electrode section 6 is coated with a material having excellent corrosion resistance such as gold, it can be used for a long time,
Malfunction can be prevented. (2) Insulation outside the conductive portion of the conductive cable can be achieved by coating an insulating film. When the periphery of the insulating film is further molded with an insulating resin, a conductive portion as shown in FIG. 6 can be formed. (3) In FIG. 6, the electrode portion is covered with a liquid permeable insulating material, but this can be obtained by molding. Examples of the liquid permeable insulating material include a clothed resin, a degreasing wire, and a resin having a water passage hole.

[0029]

As described above, according to the sensor for detecting conductive foreign matter such as permeated moisture according to the present invention, detection of conductive foreign matter, detection of presence or absence of permeated water in soil, detection of presence or absence of permeated water in a dike. It is possible to monitor the moisture penetration in the soil or to monitor the moisture penetration of the embankment.

[Brief description of the drawings]

FIG. 1 is a structural view showing a first embodiment of a sensor for detecting conductive foreign matter, particularly permeated moisture, of the present invention.

FIG. 2 is an explanatory diagram of functions of the sensor for detecting permeated moisture in FIG.

FIG. 3 is a structural diagram showing a second embodiment of a permeated moisture detection sensor according to the present invention.

FIG. 4 is an embodiment of the detection system of the present invention including an equivalent circuit.

FIG. 5 is a structural view showing a third embodiment of a permeated moisture detection sensor according to the present invention.

FIG. 6 is a structural diagram showing a fourth embodiment of a permeated moisture detection sensor according to the present invention.

FIG. 7 is a perspective view illustrating a permeated moisture detection sensor according to a fifth embodiment of the present invention.

[Explanation of symbols]

1, 21, 31, 41, 51 Conductive foreign matter (moisture penetration)
Detection sensor 2, 22, 32 First conductive cable 3, 23, 33 Second conductive cable 4 Comb-shaped anode electrode 5 Comb-shaped cathode electrode 6, 24, 35 Electrode section 11, 53 Voltage generation section 12, 54 Protection resistance part 13, 55 Permeated moisture detecting part 14 Permeated moisture 34 Third conductive cable 42 Insulating coating 43 Liquid permeable insulating coating 52 Embankment

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenji Tsuchida 3-2-2, Sachimachi, Hitachi, Ibaraki Prefecture Within Hitachi Engineering Services Co., Ltd. (72) Shuji Nakajima 3-2-2, Sachimachi, Hitachi, Ibaraki Prefecture No. 2 Within Hitachi Engineering Services Co., Ltd. (72) Inventor Tsunao Ishimatsu 3-2-2 Sachimachi, Hitachi City, Ibaraki Prefecture Within 72 Co., Ltd. Hitachi Engineering Services Co., Ltd. No. 2 in Hitachi Engineering Services Co., Ltd. (72) Inventor Jiro Tottori 3-2-2, Sachimachi, Hitachi City, Ibaraki Prefecture In Hitachi Engineering Services Co., Ltd.

Claims (8)

[Claims] A first conductive cable, a second conductive cable, and an electrode portion formed of opposing comb-like electrodes connected between the first and second conductive cables; A conductive foreign matter detection sensor for detecting a conductive foreign matter in an electrode portion from an amount of current when a constant voltage is applied between the second conductive cable and the second conductive cable. 2. The conductive foreign matter detection sensor according to claim 1, wherein a plurality of electrode portions are connected in parallel between the first and second conductive cables. 3. A first conductive cable, a second conductive cable, a third conductive cable, and a connection between the first and second conductive cables and between the second and third conductive cables. Current when a constant voltage is applied between the first and second conductive cables and between the second and third conductive cables. A conductive foreign matter detection sensor for detecting a conductive foreign matter in an electrode portion from a sensor. 4. The conductive foreign matter detection sensor according to claim 1, wherein the electrode portion has a surface made of a material having excellent corrosion resistance such as gold. 5. The conductive foreign matter detection sensor according to claim 1, wherein the conductive cable is covered with an insulating film. 6. The conductive foreign matter detection sensor according to claim 1, wherein the electrode portion is molded with a liquid permeable insulating film. 7. A conductive foreign matter detection sensor is buried in the soil,
The conductive foreign matter detection sensor according to any one of claims 1 to 6, wherein moisture in soil is detected as the conductive foreign matter. 8. A conductive foreign matter detection sensor is buried in an embankment,
The conductive foreign matter detection sensor according to claim 7, wherein moisture in the embankment is detected as the conductive foreign matter.