JPH0411162Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a conductive liquid detection sensor that detects leakage of conductive liquid.

[Conventional technology]

Conventional sensors for detecting conductive liquids include:
There are devices that detect liquid leaks and liquid levels by installing one or more in transport containers, liquid containers, transport pipes, etc. for water, sulfuric acid, hydrochloric acid, and various other conductive liquids. For example, as a sensor for detecting liquid leakage, etc., there is a sensor proposed by the present applicant.
There is one disclosed in Publication No. 96248. As shown in FIG. 3, two conductors 11 arranged in parallel with a predetermined interval are integrally covered with an insulating material 10, and an insulating material 10 covering these conductors 11 is used.
The conductor 11 has a configuration in which a plurality of through holes 12 are symmetrically bored at the upper end of the conductor 11 so that the conductor 11 is exposed to the outside.

Then, whether there is a liquid leakage is detected by applying a voltage between both conductors 11 and detecting the conductivity, or by supplying a pulse signal and checking whether a reflected signal is output or not. Can be detected.

[Problem that the invention attempts to solve]

However, although such conventional conductive liquid detection sensors can detect liquid leakage, they cannot be used alone to detect where a leak is occurring or to use a liquid level gauge. When used for such purposes, as shown in Fig. 4, a plurality of conductive liquid detection sensors a are arranged at predetermined intervals, and each of these is connected to a detector. b, which caused problems such as the installation work being troublesome and the wiring becoming complicated.

[Means for solving problems]

This invention was made by focusing on the problems of the conventional cables, and consists of a flat cable 1 in which a plurality of electric wires 2 are arranged parallel to each other at predetermined intervals and covered with an insulating material 3, and A plurality of conductors 5a are arranged on the surface of the flat cable 1 along the electric wire 2 and are arranged at a predetermined length in the longitudinal direction of the flat cable 1 at a predetermined interval from each other; 2, the conductors 5a and 5b are arranged to be insulated from each other and are at least partially exposed, and the conductor 5b serves as a common electrode. connection,
The plurality of conductors 5a are each connected to different electric wires 2 of the flat cable 1 to constitute a conductive liquid detection section.

[Effect]

A plurality of conductive liquid detection elements are arranged on the surface of the flat cable, one of the pair of conductors making up the conductive liquid detection element is connected as a common electrode, and the other is connected to a different electric wire of the flat cable. By connecting, the wiring work to connect each conductive liquid detection element and the detector can be omitted, and the terminal of the flat cable can be connected to the detector via, for example, a selection switch means. , the leakage or liquid level of the conductive liquid can be detected using a common detector, and the overall configuration can be simplified.

〔Example〕

This invention will be explained below based on the drawings.

FIG. 1 is a sectional view showing an embodiment of this invention, and FIG. 2 is a configuration diagram showing an example of a conductive liquid detection system constructed using a conductive liquid detection sensor according to this invention.

First, to explain the configuration, in FIG. 1, 1 is a flat cable, and a plurality of, for example, nine electric wires 2 are arranged in parallel at a predetermined interval.
These are covered with an insulating material 3.

As shown in FIG. 2, on the upper surface of the flat cable 1, a plurality of conductive liquid detection elements Di (i=1, 2, . . . , 10), for example, ten sets, are arranged in the longitudinal direction thereof. Each of these conductive liquid detection elements Di is
Conductors 5a, 5 are provided on both side edges of a flexible insulating substrate 4 having the same width as the width of the flat cable 1.
The conductors 5a, 5b are arranged in an insulating manner, and the conductors 5a, 5b are placed at a predetermined distance on the insulating substrate 4 that covers the upper part of each of the conductors 5a, 5b.
A through hole 6 is symmetrically drilled through which the portion 5b is exposed to the outside. In this case, the conductors 5a and 5b of each conductive liquid detection element Di are connected to the electric wire 2 of the flat cable 1.
For example, the conductor 5b is continuously extended as a common electrode, and
The conductors 5a are arranged at a predetermined length in the longitudinal direction of the flat cable 1 at a predetermined distance from each other. One end of the other conductor 5a of the conductive liquid detection element Di is connected to a different electric wire 2 of the flat cable 1, thereby forming a conductive liquid detection section.

Note that the flat cable 1 and the insulating substrate 4 of the conductive liquid detection element Di are integrally connected by a connecting means such as adhesion or welding.

The configuration of the conductive liquid detection sensor according to this invention has been described above. Next, a conductive liquid detection system using this conductive liquid detection sensor will be explained with reference to FIG.

That is, the electric wire 2 is connected at the terminal position of the flat cable 1 of the conductive liquid detection sensor S having the above configuration.
are exposed, and these ends and the ends of the conductor 5a of the conductive liquid detection element Di are connected to each fixed contact ti of a rotary switch 7a serving as a selection switch means.

On the other hand, the movable contact C of the rotary switch 7a
and a common conductor 5b of each conductive liquid detection element Di.
is connected to the input side of the detector 8.

Further, the output side of the detector 8 has the rotary
Rotary switch 7b interlocking with switch 7a
A leakage status indicator lamp 9 is connected via.

Next, the effect will be explained. Now, using the conductive liquid detection sensor S of this invention, water, sulfuric acid,
When detecting liquid leakage from objects to be detected such as hydrochloric acid or other conductive transport containers, liquid storage containers, transport pipes, etc., a conductive liquid detection sensor S having a desired number of conductive liquid detection elements Di is used. Place it along the object to be detected.

In this arrangement, flat cable 1
The electric wire 2 and the conductor 5a of the conductive liquid element _D1 are respectively connected to the detector 8 via the fixed contact ti of the rotary switch 7a, and the common conductor 5b
is directly connected to the detector 8.

In this state, a voltage is applied from the detector 8 between the common conductor 5b and the individual conductor 5a. At this time, when there is no liquid leakage from the object to be detected, the conductors 5a and 5b of each conductive liquid detection element Di are in an insulated state, so the movable contact C of the rotary switch 7a scans each fixed contact ti sequentially. Even if the conductors 5a, 5b, flat cable 1
There is no reduction in the resistance value of the circuit via the electric wire 2 and the rotary lease switch 7a, and therefore the detector 8 determines that there is no liquid leakage, and the liquid leakage status indicator lamp 9 remains off. .

In this state, when liquid leaks from a part of the object to be detected and conduction occurs between the conductors 5a and 5b of a certain conductive liquid detection element Di, the movable contact C of the rotary switch 7a moves to the fixed contact ti position. When the switch is switched to , the detector 8 detects continuity. Therefore, the detector 8 determines that there is a leak in that specific conductive liquid detection element Di, and the leak status display lamp 9 is turned on.

In addition, in the embodiment, the individual conductor 5a
Although the case where the conductors 5a and 5b are buried in the insulating substrate 4 has been described, it is also possible to cover each conductor 5a and 5b with separate insulating materials and adhere or heat-seal them to the flat cable 1. It is.

Further, in the above embodiment, a case has been described in which the conductive liquid detection element Di is embedded in the insulating substrate 4, but the present invention is not limited to this, and the conductors 5a and 5b may be disposed in an exposed state. Of course it's fine.

Furthermore, the conductors 5a and 5b can be installed on the same side of the flat cable 1 or on different sides, depending on the liquid condition in the container, pipe, etc. of the liquid to be detected. The design is subject to change.

In the above embodiment, the number of electric wires 2 constituting the flat cable is
It is of course possible to use a flat cable 1 having a larger number of electric wires 2 than the number of conductive liquid detection elements Di. Further, the flat cables 1 may be stacked.

In addition, the insulating material of the insulating substrate 4 is made of tetrafluoroethylene resin, which makes the surface water-repellent and can minimize the adhesion of moisture. can be prevented. Furthermore, when tetrafluoroethylene resin is used for the insulating substrate 4, by selecting the diameter of the through hole 6, it can be ensured that it does not function unless a certain level of liquid pressure is applied, resulting in high reliability. It is possible to provide a sensor.

Furthermore, the electric wire, the common conductor, and the insulating member covering the conductor can be made to have acid resistance and alkali resistance, and can be used to detect corrosive liquids such as sulfuric acid and hydrochloric acid.

Further, the selection switch means is not limited to a rotary switch, but electronic switch means such as a multiplexer can be applied.

Furthermore, the number of leak status indicator lamps 9 is not limited to the case where only one is installed as in the above embodiment, but the number corresponding to the number of conductive liquid detection elements Di is provided between the fixed contact of the rotary switch 7b and the detector 8. It may also be provided.

[Effect of idea]

As explained above, in this invention, by forming the conductive liquid detection part on the flat cable, the electric wires that serve as the lead wires are integrated, which simplifies and miniaturizes the overall structure of the sensor. This has the effect of making wiring work easier.

In addition, by arranging multiple conductive liquid detection elements in the longitudinal direction on the surface of the flat cable, which is a flexible strip, it is possible to easily adapt the shape of the object to be detected. It is possible to accurately detect the leakage position and liquid level position.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment to which this invention is applied, FIG. 2 is an explanatory view showing an example of use in which a detection means is connected to the sensor of this invention, and FIG. 3 is a plan view showing a conventional sensor. FIG. 4 is an explanatory diagram showing a conventional liquid position detection method. 1... Flat cable, 2... Electric wire, 3...
Insulating material, 4... Insulating substrate, 5a, 5b... Conductor, S... Conductive liquid detection sensor.

Claims (1)

[Scope of utility model registration request] A plurality of electric wires 2 arranged in parallel with a predetermined interval maintained.
a flat cable 1 covered with an insulating material 3; and a flat cable 1 which is arranged along the electric wire 2 on the surface of the flat cable 1 and is maintained at a predetermined distance from each other at a predetermined length in the longitudinal direction of the flat cable 1. a plurality of conductors 5a arranged along the electric wire 2;
and a continuously extended conductor 5b, the conductors 5a and 5b are insulated from each other and at least partially exposed, the conductor 5b is connected as a common electrode, and the plurality of conductors A conductive liquid detection sensor characterized in that 5a constitutes a conductive liquid detection section by connecting to different electric wires 2 of the flat cable 1, respectively.