JPH0318931Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to a liquid leakage detection zone that detects liquid leakage to floors, walls, and outer walls of pipes.

(b) Prior art and its problems Many of the conventional liquid leakage detection elements such as liquid leakage detection wires are cord-shaped, and even if they are band-shaped, linear electrodes are connected on the same plane through an insulator. It is arranged parallel to the When a cord-shaped type is used by laying it on the floor, there is a risk that it may lose its function due to damage caused by people passing on the floor, cars, etc., as well as the fact that the leakage detection element is not strip-shaped. However, there are drawbacks such as the need for a special saddle and the like for installation, which requires a large number of man-hours. Although they are strip-shaped, when the liquid to be detected penetrates between the linear electrodes, it is necessary to remove the sensing element and wipe it clean in order to restore the characteristics. It was a hassle to have to do it.

This invention was devised in view of the above circumstances, and aims to provide a liquid leakage detection band that is highly reliable, easy to install, and whose characteristics can be extremely easily restored after being immersed in liquid.

(c) Means for solving the problem In order to achieve the above object, this invention provides a plurality of strip electrodes in parallel, interposes a water-repellent insulator between adjacent strip electrodes, and It is characterized by exposing the entire length of the edge.

Note that at least one of the outer band-shaped electrodes is
An insulating protective layer or an adhesive layer may be formed on the outer surface.

The liquid leakage detection band according to the invention configured in this way is installed at the liquid leakage detection location with each electrode facing up and down, and the electrical characteristics such as resistance and capacitance between the electrodes are measured. Leakage is detected by changes in electrical characteristics.

After this leakage detection, the cause of the leakage is removed and the leakage remaining around the leakage detection band evaporates, flows out or is discharged. Since it is exposed, the electrical characteristics can be restored smoothly, making next leakage detection possible. In other words, if the insulator is liquid-impermeable and the leakage liquid does not enter the insulator, the insulator is water repellent, so not only will the leakage liquid not stick and remain, but the side of the strip electrode Since the entire length of the edge is exposed and there is no external coating or other factor that could cause bridging between the strip electrodes, the electrical properties are quickly restored.

Also, when the insulator is a liquid-permeable structure,
Since the insulator is water-repellent and the strip electrode extends to the side edge of the insulator (the entire length of the side edge is exposed), liquid that has entered the insulator will be able to dislodge the electrode as the liquid level decreases. It travels to the side edge and flows out to the outside. In addition, since there is no part of the leaked liquid remaining on the insulator, and no external covering or the like that could cause bridging between the strip electrodes, the electrical characteristics can be restored smoothly.

Furthermore, since the entire length of the electrode side edge is exposed,
The insulators above and below (on both sides) of the electrode are separated by the electrode, and liquid does not leak from one side to the other due to capillary action or the like in the upper and lower insulators. Therefore, in cases where there are three or more electrodes, the degree of leakage can be reliably known by individually detecting the electrical characteristics between each electrode.

(D) Embodiment As shown in FIG. 1, an insulator 3 is firmly fixed with a binder 2 between two strip electrodes 1a and 1b provided in parallel. The side edges of the insulator 3 may be substantially flush with the side edges of the strip electrodes 1a, 1b, or may protrude. If the side edges of the insulator 3 are retracted too much from the side edges of the strip electrodes 3a and 1b, there is a risk that the electrode side edges will come into contact with each other when external pressure is applied, causing the side edges of the insulator to protrude. If it is too high, the creeping resistance between the electrodes becomes too large, which is not preferable. Moreover, the strip electrode 1a,
The side surface of 1b is exposed. Strip electrodes 1a, 1b
is made of a metal plate or the like, and the insulator 3 is made of a water-repellent material such as polyethylene. Note that the strip electrodes 1a, 1
When a metal plate is used for b and polyethylene is used for the insulator 3, the binder 2 can be Admar (trade name of Mitsui Petrochemical Industries, Ltd.), Bond First (trade name of Sumitomo Chemical Industries, Ltd.), or Dumilan (trade name of Sumitomo Chemical Industries, Ltd.). (trade name of Takeda Pharmaceutical Co., Ltd.) is preferable, but
If the insulator 2 is made of other than polyethylene, a suitable binder may be used.

The liquid leak detection band of this invention constructed as described above is installed on the floor of a computer room, etc., and the band-shaped electrode 1
By measuring electrical characteristics such as resistance and capacitance between a and 1b, leakage can be detected based on changes in the electrical characteristics. For example, in the case of the resistance method, as shown in FIG. Convert to detection voltage V ₀ . This detection voltage V ₀ is determined by comparator 8 as a reference voltage.
Compare with V ₁ . Due to leakage, electrodes 1a and 1b
If the resistance _value between
becomes larger than the reference voltage _V1 , and the alarm 9 is activated to notify the user.

Next, another example of this invention will be explained based on FIG.

As shown in FIG. 3, three strip electrodes 11a,
11b and 11c are provided in parallel, and insulators 12a and 12 are placed between adjacent strip electrodes by a binder 2.
2b is fixed. Therefore, as shown in FIG.
The other ends of 4 and 15 are connected to strip electrodes 11a and 11, respectively.
When connected to the resistors 14 and 15, an AC voltage corresponding to the resistance value of the insulators 12a and 12b is obtained from the resistors 14 and 15. The AC voltage generated across the resistors 14 and 15 is converted into a DC detection voltage V ₂ , by the rectifier circuits 16 and 17.
The voltage is converted to V ₃ and compared with reference voltages V ₄ and V ₅ by comparators 18 and 19. When leakage occurs and the resistance value of the insulators 12a and 12b decreases, the detection voltage
When V ₂ and V ₃ become higher than the reference voltages V ₄ and V ₅ , the first and second alarms 20 and 21 are activated to notify of leakage.

In the embodiment shown in FIG. 3, since the insulator 12a between the strip electrodes 11a and 11b and the insulator 12b between the strip electrodes 11b and 11c are detected separately, the second alarm 21 is activated. then the first
By managing the elapsed time during which the alarm 20 is activated, it is possible to know the amount of liquid leakage and the degree of liquid leakage, and it is possible to appropriately handle liquid leakage accidents.

In the above embodiments, the number of strip electrodes may be four or more. In these plurality of strip electrodes,
At least one of the strip-shaped electrodes located at both ends (strip-shaped electrodes 11a and 11c in the case of FIG. 2) has a protective insulating layer formed on its outer surface to prevent the strip-shaped electrode from being damaged by people or cars. Just leave it as .
In addition, at least one of the strip electrodes located on both outer sides is fixed to the floor, etc. by forming an adhesive layer such as double-sided adhesive tape or adhesive on the outer surface of the electrode, either directly or on a protective insulating layer. Just make it easier. Furthermore, when detecting a liquid containing water by the resistance method, the insulators 3, 12a, and 12b are made of a water-repellent insulating material such as polyethylene, and the surface resistance and/or volume resistance of the insulators are In addition to preventing the value from decreasing due to moisture, etc., it is immediately detected when the water level reaches the second electrode from the bottom, and when the water subsides, the inter-electrode resistance value immediately returns to normal. In addition, when detecting insulating liquids such as oil using the capacitance method, insulators 3 and 12
a and 12b are made of a braided body made of polyethylene, which has a low dielectric constant, is oil resistant, has a gap, and has liquid permeability, thereby making it easy for liquid to enter and exit, and to prevent static It is desirable to be able to detect intrusion and outflow into the container using the capacitance method.

(E) Effect As described above, this device uses a plurality of parallel strip electrodes that are formed in a strip shape with an insulator interposed between them, so there is no need for a saddle or the like as in conventional liquid leakage detection elements, and the electrodes can be placed on the floor. It is very easy to install on a surface, and it is less likely to be damaged by people, cars, etc. In addition, if the number of strip electrodes is about two or three, it can be formed very thinly, so people will not trip over the liquid leakage detection strip of this invention, so it can be used safely in areas where people pass.

Furthermore, since the insulator is made water repellent and the entire length of the side edge of the electrode is exposed, the electrical characteristics can be restored smoothly. In other words, it is possible to recover quickly.

Furthermore, when three or more strip electrodes are used, the insulator between them is water repellent and the entire length of the side edge of each electrode is exposed, so by individually detecting the electrical characteristics between each strip electrode, This has the advantage that the degree of leakage can be known, the reliability of leakage detection is improved, and countermeasures against leakage accidents can be taken more accurately.

[Brief explanation of drawings]

Figure 1 is a perspective view showing an example of this invention, Figure 2 is a detection circuit using the leak detection band shown in Figure 1,
FIG. 3 is a perspective view showing another example of this invention, and FIG. 4 is a detection circuit using the leak detection band shown in FIG. 3. 1a, 1b, 11a to 11c...Strip electrode, 2
... Binder, 3, 12a, 12b ... Insulator.

Claims (1)

[Claims for Utility Model Registration] (1) Consisting of a plurality of strip-shaped electrodes arranged in parallel, a water-repellent insulator is interposed between adjacent strip-shaped electrodes, and the entire length of the side edge of each strip-shaped electrode is exposed. A liquid leakage detection band characterized by: (2) The liquid leakage detection band according to claim (1) of the utility model registration, characterized in that at least one of the outer band-shaped electrodes has an insulating protective layer formed on its outer surface. (3) Claims (1) or (2) of the utility model registration, characterized in that at least one of the outer band-shaped electrodes is formed with an adhesive formed on its outer surface.
Leakage detection band as described in section.