JPH0240530Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a water detection cable with improved detection performance capable of detecting trace amounts of water.

[Technical background of the invention and its problems] In recent years, water detectors have been installed to detect water in order to protect computers and various electrical equipment from water damage caused by water leaks and condensation. .

A sensor used in such a water detector is, for example, as shown in Fig. 1, in which two rectangular conductors 1 are pasted in parallel on one side of an insulating tape 2 such as plastic tape at a predetermined interval. This is pasted or wrapped around a vertical surface so that both bare conductors are above and below, and the electrical resistance between the conductors increases due to the water that falls down the vertical surface and adheres to these conductors. A water detection cable is known that detects water by detecting a drop in the amount of water.

In such a cable, water leakage is detected based on the resistance ratio between the normal state and the submerged state, so the larger this ratio is, the better the detection sensitivity is. By the way, the width is 1.25mm.
Two strips of stainless steel tape 0.12mm thick, 9.2mm wide,
When a water detection cable is installed vertically with a structure in which it is attached parallel to one side of magnetic tape with a thickness of 1.8 mm at intervals of 1.8 mm, the normal resistance is 5 × 10 ¹⁰
Ω/30cm, but the resistance when submerged is approximately 160K
It was Ω/30cm.

Although it has been possible to reduce the resistance value during submergence to a certain extent in this way, it has been desired to further reduce the resistance, that is, to improve the sensitivity.

[Purpose of the invention] The present invention was created in response to the above-mentioned problems, and the purpose is to provide a water detection cable that has improved sensitivity by increasing the reduction in electrical resistance when water drops pass through it. do.

[Summary of the invention] In other words, the water detection cable of the present invention has two rectangular bare conductors arranged in parallel at a distance on a flat insulating tape, and these are placed on a vertical plane so that both bare conductors are above and below. In the water detection cable, water is detected by detecting a decrease in electrical resistance between the bare conductors due to water adhering across both the bare conductors. It is characterized by a groove formed on the top for a water trap.

Examples of the conductor used in the present invention include rectangular annealed copper wire, stainless steel wire, aluminum wire, and tin-plated wires. The size of this rectangular conductor is, for example, 0.05 to 0.3 mm thick x 1 mm wide.
~2mm is suitable.

Suitable insulating tapes used in the present invention include plastic tapes made of polyethylene, polyethylene terephthalate, polyvinyl chloride, etc., and magnetic tapes made of these materials mixed with magnetic materials.

[Example of the invention] Next, an example of the invention will be described. In addition,
Components common to those in FIG. 1 are designated by the same reference numerals.

Embodiment Figure 2 shows two rectangular conductors 1 pasted in parallel on one side of an insulating tape 2 such as plastic tape at a predetermined interval, and a V-groove 3 for a water trap on the insulating tape between the conductors. This is an example in which two wires are provided in the longitudinal direction.

3 shows an example in which a U groove 4 is provided instead of a V groove, and FIG. 4 shows an example in which a large number of intersecting lines 5 are provided.

In a water detection cable constructed in this way, when the bare conductors are attached or wrapped around a vertical surface with the top and bottom conductors facing each other, water droplets that trickle down the vertical surface are trapped in the water trapping groove. The water droplets form a thick water film between both bare conductors, reducing the electrical resistance between both bare conductors and improving sensitivity.

By the way, for the water detection cable mentioned above, which has one or two V-grooves, the resistance is 110kΩ/30cm for one V-groove, and 110kΩ/30cm for two V-grooves.
It was 90kΩ/30cm.

[Effects of the invention] As explained above, in the water detection cable of the invention, the electrical resistance decreases more when water drops pass through it, and the sensitivity improves.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional water detection cable, Figures 2 and 3 are cross-sectional views of an embodiment of the water detection cable of the present invention, and Figure 4 is a cross-sectional view of an embodiment of the water detection cable of the present invention. FIG. 1...Flat conductor, 2...Insulating tape, 3, 4...
...stasis, 5...streak, 6...protrusion.

Claims (1)

[Scope of utility model registration request] Two strips of rectangular bare conductors are arranged parallel to each other with an interval on a flat insulating tape, and these are arranged on a vertical plane so that both bare conductors are one above the other. , a water detection cable configured to detect water by detecting a decrease in electrical resistance between the bare conductors, characterized in that a groove for a water trap is formed on the insulating tape between the bare conductors. water detection cable.