JPS6233539B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is a method (synonymous with a method) of detecting information via an optical transmission body placed in an area where information is to be detected.
In particular, the present invention relates to an information detection method that can be applied to, for example, fluid leakage detection in a long transportation path, light leakage detection in an optical transmission path, etc.

<Prior art and its problems> Conventionally, in oil transmission pipelines, electric cables whose dielectric constant changes depending on oil are installed along the pipelines, and this is used as an oil leak detection line to detect electricity caused by oil leaks. There are devices that detect oil leak accidents by monitoring changes in impedance that occur in the cable at the end of the cable, and devices that use the weight of oil leaks collected in an oil sump to press down a spring-loaded rod to indicate oil leaks. Some have used spring-structured detectors with closed contacts to detect oil leaks by placing them at each detection point in the longitudinal direction of the pipeline. Since it is difficult to increase the amount of change, this must be detected by converting it into pulses.Moreover, even if the detection signal is converted into pulses in this way, it will be affected by losses due to electric cables and external noise added to it. Since the pulses do not travel far enough, it has not been possible to satisfactorily detect oil leaks by installing such a means in a long oil pipeline.

In addition, in the latter case, expensive detectors must be installed at each of the many detection points set in the long pipeline, which requires a large number of parts and a lot of work to install them. This resulted in uneconomical equipment requirements.

The above describes the case where the object to be detected is a liquid such as oil, but even when detecting a gas leak using the former detection method described above, the same problems arise as when detecting a liquid. When detecting light leakage from an optical transmission body using this method, in addition to the above-mentioned problems, there is an uneconomical need to incorporate photoelectric converters at multiple locations (each light leakage detection part) on the electric cable, and furthermore, the latter detection method Since this method detects the weight of leaked materials, it was not possible to apply it to the detection of gas or light leaks.

As other conventional techniques, means for optically detecting the presence or absence of information are disclosed in Japanese Patent Application Laid-open No. 53-37494 and Japanese Patent Application Laid-open No. 53-37494.
It is disclosed in each publication of No. 76889.

With these methods, the presence or absence of leaked information can be detected without causing the influence of external noise due to electrical means or the uneconomical effects of equipment due to mechanical means.
It is not possible to simultaneously detect the location where the information is generated.

In view of the above-mentioned problems, the present invention aims to provide an optical information detection method that can detect the presence or absence of information in an area where information should be detected, and at the same time can detect the location where the information is generated.

<Means for Solving the Problems> In order to achieve the intended purpose of the information detection method using an optical transmission body of the present invention, the area in which the presence or absence of an information medium is to be detected is divided into a plurality of detection sections. , an optical transmission body for information detection is equipped with a light transmission section at one end and a light level detection system at the other end, and there is a gap between the light transmission section and the light level detection system in the optical transmission body. A plurality of detection sections for receiving the information medium are provided adjacent to each other at intervals, and the amount of information received by each of these detection sections is different from each other. The detection sections of the optical transmission body are distributed in each detection section of the information detection area, and the optical signal transmission state of the optical transmission body from the light transmission section to the light level detection system is , when an information medium intrudes into any detection unit, the intrusion of the information medium;
The light level detection system detects a change in the optical signal due to the amount of information received specific to the detection unit into which the information medium has entered, and it is determined that the information medium is present in the detection area into which the information medium has entered. Detect.

<Example> Hereinafter, an example of the information detection method according to the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a passage as a fluid transport passage or as an optical transmission body, and the passage 1
If this is a fluid transport path, it is composed of a tube or the like, and if it is an optical transmission line, it is composed of an optical fiber cable.

The feed path 1 has one end serving as a starting end 2 for fluid transport or optical transmission, and the other end serving as a terminal end 3, but in some cases, these ends 2 and 3 are , one or both of them may serve as a relay end, and when this transmission route 1 is laid, erected, or buried at a required location, its entire length in the longitudinal direction is the zone where leakage is to be detected, that is, a band-shaped area. The detection band L is divided into a large number of detection sections l ₁ , l ₂ , l ₃ . . . ln _-2 , ln _-1 , ln.

In the present invention, an optical transmission body 4 is arranged along the belt-shaped area L where information is to be detected, and information such as a leakage object is detected via the optical transmission body 4.

The optical transmission body 4 is made of an optical fiber or an optical fiber cable, which is an assembly of the fibers, and a light transmitting section 5 equipped with a light source or an electric/optical converter that converts electricity into light is provided at one end. , an optical power meter at the other end, and an optical power meter that converts light into electricity.
A light level detection system 6 including an electric converter and the like is connected.

Furthermore, this optical transmission body 4 has each detection section l ₁ to ln
A plurality of detection units 7 ₁ , 7 ₂ , 7 ₃ . . .
...7n _-2 , 7n _-1 , 7n are provided.

As will be described later using FIG. 2 as an example, each of these detection units 7 ₁ to 7n is designed to allow leakage matter (information medium) from the above-mentioned feed path 1 to enter or pass through, and each detection unit 7 ₁ The amount of information received at ~7n is individually different, and the integrated value when the amount of information received by each detection section is integrated by combinations of arbitrary locations and arbitrary numbers is unequal. The amount of information accepted by each of these detection units 7 ₁ to 7n is set.

Below, regarding this point, the _second
To explain with an example in the figure, the detection unit ₇₁ configured using the separation space of the optical transmission body 4 includes convex lenses 9a and 9b placed at a focal distance from the separation terminals 8a and 8b, and It consists of a cylindrical body 10 that surrounds and fixes each of the separation terminals 8a, 8b and convex lenses 9a, 9b, and an inlet hole 11 that opens between the biconvex lenses 9a, 9b is formed on the circumferential surface of the cylindrical body 10.
A and an exit hole 11b are bored.

In this case, the transmitted light to the optical transmission body 4 is as follows: separation terminal 8a → convex lens 9a → convex lens 9b → separation terminal 8
b, and passes through the detection part _71. On the other hand, information media such as liquid, gas, and light pass from the inlet 11a of the cylinder 10 to the outlet 11b of the detection part _71.
and the detection unit 7 ₁
If an information medium is inserted into the optical transmitter 4, the optical transmission state of the optical transmitter 4 will change.

In this case, there are two ways of changing the optical transmission state. For example, if the information medium is a light-shielding liquid or gas, the amount of light from the optical transmission body 4 will be attenuated in the detection unit ₇₁ ; If it is light, the amount of light mentioned above will be increased or modulated.

Furthermore, the degree of change in the detection section ₇₁ is proportional to the amount of information received by the detection section, and the above-mentioned change value is determined by setting the magnitude of the same capacity.

The amount of information received by this detection ₇₁ can be set to a predetermined value by appropriately setting the width d between the biconvex lenses 9a and 9b when the inner diameter of the cylinder 10 is constant. In order to control the amount of intrusion, the amount of permeation, etc., the diameter of each hole of the inlet hole 11a or the outlet hole 11b,
The amount of information received can be set to a desired value by appropriately determining the number of holes, and the capacity value can also be set by adjusting the inner diameter of the cylinder 10.

According to the above example, the amount of information received by the detection unit ₇₁ can be set to a desired value, and the amount of information received by the other detection units ₇₂ to 7n is determined in the same way.
In setting the amount of information received by each of the detections 7 ₁ to 7n by the above-mentioned means, etc., it is necessary to set the amount of information received by each of the detections 7 1 to 7n by combining arbitrary locations and numbers so that the amounts of information received are different from each other as described above. Each of the detection units 7 ₁ to 7n is configured such that the integrated values of the information reception amounts of each of the detection units 7 ₁ to 7n are unequal values.
7n information acceptance amount is set.

In other words, to illustrate this point with a specific example, the amount of information received by each of the detection units 7 ₁ , 7 ₂ , 7 ₃ , 7 ₄ , etc. is determined by the optical attenuation rate when the information medium enters inside these units. Or the increase rate (%) is (7) ₁ = 5, (7) ₂ =
The magnitude is set as 10, (7) ₃ = 11, (7) ₄ = 13, etc. Therefore, the individual values of the amount of information received in each detection section are different from each other, and the transmission When the amount of light is 100, any combination of arbitrary locations and arbitrary numbers will yield 100 x (7) ₁ x (7) ₂ = 100 x 0.95 x 0.90 = 85.5 100 x (7) ₁ x (7) ₄ = 100 ×0.95×0.87＝82.65 100×(7) ₂ ×(7) ₃ =100×0.90×0.89＝80.1 100×(7) ₂ ×(7) ₃ ×(7) ₄ =100×0.90×0.89×0.87= As shown in 69.687, the integrated value (decreasing rate) becomes an unequal value, and the value also becomes an unequal value when the increasing rate is integrated.

In the case where the present invention consists of the above-described embodiment, light is passed through the optical transmission body 4 from the light transmitting section 5 toward the optical level detection system 6, and is monitored from the optical transmission path 1 by the optical level detection system 6. This involves detecting information using leaked material as an information medium.

In this information detection, a state in which there is no leakage accident in the transmission line 1 is regarded as normal, and in the same state, the optical transmission body 4
The information medium (leakage) from the transmission path 1 will not enter each of the detection sections 7 ₁ to 7n, and therefore the optical signal transmitted from the light transmission section 5 to the light level detection system 6 will not change. First, the detection system 6 comes to display a normal state based on the unchanged optical signal.

Furthermore, in this information detection, if a leakage accident occurs in any of the detection sections l ₁ , l _{2 , l 3} . The leaked material enters the detection unit 7 ₁ in the l ₁ ) as an information medium, causing a change in the optical signal of the optical transmission body 4 through the medium, which is displayed by the optical level detection system 6. and even a buzzer,
It also becomes an alarm state via the lamp.

In other words, if the above-mentioned feed route 1 is a transport route for oil, gas, etc., and a leakage accident occurs in the detection section _l1 exemplified above, the leaked fluid (information medium) is transferred to the detection section _71.
When the above-mentioned transmission path 1 is an optical transmission body, the leaked light (information medium) at this time enters the detection unit 7 and attenuates the optical signal of the optical transmission body 4. ₁ and increases or modulates the optical signal of the optical transmission body 4, and such a change in the optical signal is displayed by the optical level detection system 6.

Therefore, a light level detection system 6 that uses an alarm etc.
When the reception status of the information medium is displayed by the detection system 6 during the monitoring system, it becomes immediately clear that a leakage accident has occurred in the transmission path 1.

Also, the amount of information received by the detection unit ₇₁ is different from that of the other detection units 7.
₂ to 7n, and the degree to which the optical signal is changed (attenuated or increased) by the information medium that has entered the detection unit ₇₁ is also determined, so the light level is determined based on the light transmittance after the change. The detection system 6 comes to display the detected value, and from this detected value it is simultaneously revealed that a leakage accident has occurred in the detection section _l1 .

Normally, in the above-mentioned feed path 1, it is rare for a leakage accident to occur simultaneously in a plurality of detection sections.Therefore, as described above, the amount of information received by each of the detection sections ₇₁ to 7n is individually made different. This enables the purpose of detecting leakage accidents and confirming the location where the accident occurred, but even if a leakage accident occurs at multiple locations at the same time, these accidents and their respective locations can be detected as follows. It becomes clear.

In other words, as exemplified above, each detection unit 7
The amount of information received by ₁ , 7 ₂ , 7 ₃ , 7 ₄ ...... has a light attenuation rate or increase rate (%) of 5, 10, 11, 13...
The detection units 7 ₁ and 7 ₂ , 7 ₁ are set as follows.
and 7 ₄ , 7 ₂ and 7 ₃ , 7 ₂ and 7 ₃ , and 7 ₄ , the respective attenuation rate integrated values are 85.5...A, 82.65
…B, 80.1…C, 69.687…D. Therefore, when the light level detection system 6 detects and displays based on the value of A, the detection units 7 ₁ and 7 ₂ At the same time, a leaked object (information medium) has entered, and it is therefore found that a leakage accident has occurred in the detection sections l ₁ and l ₂ , and similarly, the detection sections 7 ₁ and 7
The value of B based on ₄ indicates an accident in the detection sections l ₁ and l ₄ , the value of C based on the detection sections 7 ₂ and 7 ₃ indicates an accident in the detection sections l ₂ and l ₃ , and the detection section D caused by the detection sections 7 ₂ , 7 ₃ , and 7 ₄ indicates an accident. With the values of , it becomes clear that the accident occurred in the detection sections l ₂ , l ₃ , and l ₄ .

The above is a method for detecting leakage by using the leakage material in the transmission path 1 as an information medium, but in such information detection, the detection band L should cover the transmission path 1 and the optical transmission body 4. An outer cylinder may be provided, and partition walls for each of the detection sections l ₁ to ln may be provided within the outer cylinder.

Furthermore, when the sending path 1 is an optical transmission path, a light guide (such as an optical fiber or a prism) that guides leaked light into each of the detection sections 7 ₁ to 7n may be attached to each of the detection sections.

Further, each of the detection units 7 ₁ to 7n may be configured as shown in FIG. 3. In this case, one disconnection terminal 8a of the optical transmission body 1 is configured as in FIG. 2, and the other disconnection terminal 8b is configured as shown in FIG.
In this case, by appropriately setting the separation width h and the diameter of the terminal 8b, the amount of information received by each of the detection sections 7 ₁ to 7n can be set to a desired value as described above.

Naturally, the method of the present invention can also be implemented in addition to detecting leaked objects. For example, it can be used to detect whether liquid, gas, light, etc. have entered a specific area as an obstacle, or whether liquid, gas, light, etc. emitted from a certain point, Information such as whether an information medium such as light has passed a predetermined point can also be detected.

Furthermore, when performing information detection as described above, a plurality of optical transmission bodies 4 are arranged in parallel to combine changes in the optical transmission state in each optical transmission body,
This may allow information to be detected within a wide area.

<Effects of the Invention> As explained above, the information detection method according to the present invention detects the desired information using optical means including an optical transmission body, so it is free from the influence of external noise seen in electrical means. Not only is there no diseconomie in terms of equipment that occurs with mechanical means, but the following effects can be obtained.

In other words, with respect to each detection section of the optical transmission body distributed in each detection section of the area where information should be detected, the amount of information received by these detection sections is different from each other, so the transmission state of the optical signal in the optical transmission body , when an information medium enters an arbitrary detection section, the amount of information medium corresponding to the amount of information received enters the detection section, and the optical signal in the transmission state undergoes a fixed change according to the amount of intrusion. Come.

Therefore, when the transmission state of the optical signal is monitored through the optical level detection system, the presence of an information medium can be detected by the change in the optical signal, and the amount of change in the optical signal can detect the presence of the information medium. A certain position of the medium can be detected at the same time.

In addition, as in the embodiment, when the detection units having different amounts of information reception satisfy the condition that the cumulative value of the amount of information reception for all combinations of 2 or more is different, Even if the medium enters multiple detection units at the same time,
The presence of an information medium in a predetermined detection area can be detected together with these positions.

[Brief explanation of the drawing]

Fig. 1 is a schematic explanatory diagram showing one embodiment of the method of the present invention, Fig. 2 is an enlarged sectional view showing one example of the detection section in the above, and Fig. 3 shows another example of the same detection section. It is an enlarged view. 4... Optical transmission body, 5... Light transmitting section, 6... Light level detection system, 7 ₁ to 7n... Detection section, L... Strip area, l ₁ to ln... Detection section.

Claims (1)

[Claims] 1. An area where the presence or absence of an information medium is to be detected is divided into a plurality of detection sections, and an optical transmission body for information detection is equipped with a light transmitting section at one end and a light transmitting section at the other end. A light level detection system is provided, and a plurality of detection parts for receiving the information medium are provided at adjacent intervals between the light transmission part and the light level detection system in the optical transmission body. At the same time, the amount of information received by each of these detection parts is different from each other, and the above-mentioned optical transmission body is placed in the area where information should be detected, and each detection part of the optical transmission body is connected to each detection area in the information detection area. When an information medium enters any detection section in the optical signal transmission state of the optical transmission body from the light transmitting section to the optical level detection system, the information medium is intruded and the information medium is detected. A light that detects the presence of the information medium in the detection area into which the information medium has entered by detecting a change in the optical signal due to the amount of information received specific to the intruding detection part using the light level detection system. Information detection method using a transmitter. 2. Each of the detection units having different amounts of information reception is configured to satisfy the condition that the integrated value of the amount of information received by all combinations of two or more of them is different from each other. Detection method.