JPH11190676A - Leakage detection relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure an immediate and sure detection of leakage of water solution by providing a constitution where a nonconductive substance dissolves when moisture or water content leaks in a relay disposed in a disconnection manner by a soluble nonconductive substance so that electrodes are brought into contact to generate supplying a current. SOLUTION: A soluble nonconductive substance 1 is fixed by means of electrodes 2, 3 and springs 4, 5. As the nonconductive substance that can be used under a certain level of moiture causing no problem, carbonhydrate, sugar or the like is listed. Though they do not cause a current supply at the time of absorbing water content, each of them is dissolve within 5 min. when it is subjected to water directly, so that the electrodes 2, 3 are pushed by the springs 4, 5 to generate contact and current supply. Under the surroundings where a low level of moisture must be maintained, as the soluble nonconductive material chrolide, calcium chrolide or the like is listed. The substance is half- dissolved or dissolved under a high moisture condition or when it has a small amount of water content, so that the electrodes 2, 3 are pushed to generate contact and current supply. With the use of this current supply, this relay can drive an alarm device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a configuration of a leak detecting relay using a soluble non-conductive substance, a deliquescent non-conductive substance, and an expanding material which have a strong reactivity to moisture. In addition, it is concerned with taking protective measures against such means as using water with the intention of destroying critical electronic components.

[0002]

2. Description of the Related Art As a method for preventing a communication failure due to leakage of water or the like in an optical cable, there is a coated cable mixed with a water-swellable crosslinked sodium polyacrylate. In addition, as a water sensor, there are various sensors using a change in electric resistance and an optical change.

In addition, a powdery water-insoluble water-absorbent resin is put into a water-permeable bag, and water leaks in and water infiltrates, and the swelling of the water-insoluble water-absorbent resin increases the size of the bag, causing the circuit electrodes to come into contact and conduct electricity. There is a leak detection relay.
4350).

[0004]

Various sensors utilizing changes in electrical resistance and optical changes are expensive. Leak detection relays that use powdered water-insoluble water-absorbent resin in a water-permeable bag are advantageous in terms of cost, but this leak detection relay can prevent water from entering the bag even if water leaks. And the sensitivity was low because the start of swelling of the water-absorbent resin was delayed correspondingly. On the other hand, in a leak detection relay using only a powdery water-insoluble water-absorbing resin instead of a bag-like shape, when water invades, the water-absorbing resin in the peripheral part swells first and the central part absorbs water. Since the swelling speed is low because water impinges on the conductive resin layer, the sensitivity is low and the practicability is poor.

[0005] In view of the above circumstances, it is an object of the present invention to provide an inexpensive leak detection relay that can reliably detect the leak of aqueous liquid immediately.

[0006]

A precision machine such as an electric part is detected when exposed to moisture and greatly damaged by dew condensation, or when a jet of water (water jet processing) is used for destruction. Measures are needed. In this method, a switch input occurs due to the intrusion of moisture into the leak detection relay. As a switch input mechanism, a leak detection relay composed of a power supply (battery), a soluble non-conductive material, electrodes, wiring, and a resistor as shown in FIG. 1 is proposed. When moisture or moisture leaks from a leak detection relay installed in a state where it is cut off by a soluble non-conductive substance, the non-conductive substance deliquesces, dissolves, or flows out. As a result, the electrodes are brought into contact and energized. Using this, an alarm device such as a buzzer sound and lamp lighting can be driven. Further, a leak detection relay including a power supply (battery), an absorber, electrodes, wiring, and a resistor as shown in FIG. 2 is proposed. When a leak of aqueous liquid occurs in a leak detection relay in which a pair of positive and negative electrodes having a certain distance and an absorber that absorbs water and expands are installed, the absorber expands and positive and / or negative The absorber is placed so as to push out the electrodes. Here, the aqueous liquid includes all liquids containing water. The movement of the positive and / or negative electrodes causes the two electrodes to come into contact with each other. Here, by using an absorber formed by fixing a water-insoluble water-absorbent resin in a water-insoluble fiber matrix as an absorber, water contact with the absorber at the time of water leakage is fast, and after contact, the inside of the sheet is In addition to being porous, the water is induced by the capillary action of the fibers, so that water infiltrates rapidly, and the water-absorbent resin in the matrix rapidly swells as soon as it comes into contact with water. Therefore, the response time from the leak to the detection is shortened.

As the water-insoluble fiber, all water-insoluble fiber materials such as natural or synthetic fibers made of cotton, rayon, polypropylene, polyester, nylon and the like, and mixtures thereof (such as blended products) can be applied.

Examples of the water-insoluble water-absorbent resin include cross-linked polyacrylic acid neutralized products, neutralized self-cross-linked polyacrylic acid products, partially hydrolyzed polyacrylamide cross-linked products,
Starch-acrylic acid graft copolymer crosslinked product, starch-acrylonitrile graft copolymer hydrolyzate,
Crosslinked products of vinyl acetate-acrylate copolymers, crosslinked products of acrylic acid-acrylate copolymers, crosslinked products of isobutylene-maleic anhydride copolymers, crosslinked products of carboxymethyl cellulose, crosslinked products of sulfonated polystyrene, and the like. . These may be used alone or in combination of two or more.

The water-insoluble water-absorbent resin generally has a water-absorbing performance against pure water of 30 to 1000 ml / g, preferably 100 to 1000 ml / g.
It is 600 ml / g. That is, usually 1 g of the resin is 30 to
Since it absorbs a large amount of water (1000 ml) and becomes swollen by that amount, it causes the action of pushing the electrode.

The shape of the absorber is not particularly limited. For example, one or more sheets, preferably two or more sheets, are stacked in the direction in which they move when swelling with water. By laminating, the water absorption speed is increased, and the response time from leaking to detection is shortened.

The structure of the absorber is, for example, the following (1) to
(4). (1) Absorber formed from fiber composite of natural or synthetic water-insoluble fiber and fibrous water-insoluble water-absorbent resin: In this absorber, natural or synthetic water-insoluble fiber and fibrous water-insoluble water-absorbent are used. The ratio of the resin is usually 30:70 to 9 by weight.
5: 5. (2) Absorber formed from heat-sealed natural or synthetic water-insoluble fiber and powdered water-insoluble water-absorbent resin using a thermoplastic resin: In this absorber, natural or synthetic water-insoluble fiber is used. The weight ratio of the water-insoluble water-absorbent resin to the water-insoluble water-absorbent resin is usually 10:90 to 70:30, and the amount of the thermoplastic resin to 100 parts by weight of the water-insoluble water-absorbent resin is usually 1 to 20.
Parts by weight. As the thermoplastic resin, a fine powder or a short fiber is preferably used. (3) Nonwoven fabric 2 made of natural or synthetic water-insoluble fiber
Absorber made by laminating sheets in which a powdery water-insoluble water-absorbent resin is interposed between two or more sheets: In this absorber, the ratio of the nonwoven fabric to the water-insoluble water-absorbent resin is usually 40 by weight. : 60 to 95: 5. As the fixing means, a method of fixing with a needle punch or a method of spot bonding between nonwoven fabrics using an adhesive is suitably used. (4) Absorber made by laminating a nonwoven fabric in which a powdery water-insoluble water-absorbent resin is dispersed and held in a natural or synthetic water-insoluble fiber matrix: In this absorber, the water-insoluble fiber and the water-insoluble water-absorbent resin are used. Is usually 50: 5 by weight.
0 to 97: 3.

[0012]

EXAMPLE 1 The circuit shown in FIG. 1 is effective when there is always a certain degree of humidity, such as in a submarine tunnel, which does not matter. The soluble non-conductive substance 1 is fixed to the electrodes 2 and 3 and the springs 4 and 5. These are provided in the container 6. There are many types of the soluble non-conductive substance 1 used here.
Typical substances such as carbohydrates and sugar do not conduct electricity even if moisture is absorbed by the substance in a high humidity state. However, if water or other liquid is directly applied to the soluble non-conductive substance, it will dissolve within 5 minutes and both ends will be dissolved. The electrodes 2 and 3 are pushed out by the springs 4 and 5, and contact and energization occur.

Embodiment 2 In an environment where a low humidity state must always be maintained, such as a place where precision equipment is installed, the soluble non-conductive substance 1 in the circuit shown in FIG.
It is effective to use a soluble non-conductive substance that has deliquescence and a high ionization tendency. There are many types of soluble non-conductive substances, but when chloride, calcium chloride, sodium chloride, etc. are used as typical substances, the soluble non-conductive substance is soluble when the circuit installation space is high humidity or when a small amount of moisture is contained. The non-conductive substance is semi-dissolved or dissolved, and the electrodes at both ends are pushed out by a spring, and contact and current flow occur. Similarly, a filter paper immersed and dried in a saline solution or the like, which is an easily energized liquid, was sandwiched between the electrodes. The salt contained in the paper was deliquescent in about 3 minutes due to the humidity of 80% RH or more, and electricity was supplied.

Embodiment 3 The mechanism shown in FIG. 2 is effective as a leak detection relay using a material that expands by absorbing moisture. At locations where a leakage accident is expected to occur, absorbers 9 and 10 that expand by absorbing moisture are installed on a pair of positive and negative electrodes 7 and 8 having a certain interval in the circuit. For example, as shown in FIG. 2, five sheets each having a thickness of 5 mm in which a polyester fiber and a fibrous water-insoluble water-absorbent resin are combined at a weight ratio of 50:50 as an absorbent body which absorbs and expands water are laminated. Used. When water leaks, the absorber expands within 5 seconds and pushes out the electrode. This causes the electrodes to come into contact,
The alarm built into the circuit is switched on.

[0015]

As described above, by installing a device for issuing an alarm when moisture is mixed in the leak detection relay, damage to the equipment due to the leak can be prevented beforehand, and the jet water for the purpose of destruction can be prevented. It can take protective measures against the cutting of electronic component containers due to the application of, and plays an important role in preserving the living environment and in today's information society.

The following effects are obtained particularly when an absorber is used. (1) Since the water-insoluble water-absorbent resin can come into direct contact with water, the absorption start is early due to the capillary action of the fiber matrix. (2) An absorber having a desired shape can be easily formed by cutting or laminating.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the structure of a leakage detection relay using a soluble non-conductive substance.

FIG. 2 is a diagram illustrating the structure of a leak detection relay using a water-absorbing swollen body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Soluble non-conductive substance 2, 3, 7, 8 Electrode 4, 5 Spring 6 Container 9, 10 Absorber

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshio Takahashi 1-3-1 Gotenyama, Musashino City, Tokyo NTT Advanced Technology Corporation (72) Inventor Mieko Tsubamoto Musashino City, Tokyo 1-3-3 Gotenyama NTT Advanced Technology Co., Ltd. (72) Inventor Yoji Fujiura 1 Sanyo Kasei Kogyo Co., Ltd., 11-11, Hitotsubashi-Honcho, Higashiyama-ku, Kyoto-shi, Kyoto (72) Inventor Yukio Zeniya, 11-11, Hitotsubashi-Honcho, Higashiyama-ku, Kyoto, Kyoto Prefecture Inside Sanyo Chemical Industries Co., Ltd. Fumio Hosoya 1847 Sugo, Akiruno-shi, Tokyo Hosoya Pyro Co., Ltd.

Claims (3)

[Claims] 1. A leakage detection relay characterized in that a soluble non-conductive substance which deliquesces or dissolves when moisture or moisture enters a circuit and which has a low electric resistance in a semi-dissolved or aqueous solution state is interposed between electrodes. 2. A pair of positive and negative electrodes having a certain distance in a circuit and an absorber formed by fixing a water-insoluble water-absorbent resin in a water-insoluble fiber matrix, the absorber being positively and / or positively swelled by water absorption. Alternatively, a leakage detection relay characterized by being installed so as to push a negative electrode and move it to a position where both electrodes are in contact with each other. 3. The leak detection relay according to claim 2, wherein the absorber is one of the following. (1) An absorber formed from a fiber composite of a natural or synthetic water-insoluble fiber and a fibrous water-insoluble water-absorbent resin. (2) An absorber formed from a natural or synthetic water-insoluble fiber and a water-insoluble water-absorbent resin in a powdered form fused with a thermoplastic resin. (3) An absorber obtained by laminating a sheet in which a powdery water-insoluble water-absorbent resin is sandwiched between two or more nonwoven fabrics made of natural or synthetic water-insoluble fibers. (4) An absorber formed by laminating a nonwoven fabric in which a powdery water-insoluble water-absorbent resin is dispersed and held in a natural or synthetic water-insoluble fiber matrix.