JP2006184070A

JP2006184070A - Optical sensing device

Info

Publication number: JP2006184070A
Application number: JP2004376176A
Authority: JP
Inventors: Takashi Kobashi; 隆小橋; Takashi Suzuki; 隆鈴木
Original assignee: Azbil Corp
Current assignee: Azbil Corp
Priority date: 2004-12-27
Filing date: 2004-12-27
Publication date: 2006-07-13

Abstract

【課題】複数の反射形光センサを用いて多点検出を行う場合であっても、その設備コストを安価に抑えることのできる光センシング装置を提供する。
【解決手段】一対の光導入部と光導出部とを備え、センシング部に付着する液体の有無に応じて上記光導入部から導入された光を選択的に前記光導出部に伝播するｎ個（ｎ：２以上の自然数）の光センサ(１)を備えたものであって、特に上記複数の光センサにおける上記各光導入部と光導出部とを［ｎ−１］本の中継用光ファイバ(３)を用いて順次直列に連結し、中継用光ファイバにより直列に連結された光センサ列における始端側光センサの光導入部および終端側光センサの光導出部に、光検出器本体まで延設される一対の伝送用光ファイバ(４ａ,４ｂ)の一端をそれぞれ連結する。
【選択図】図１PROBLEM TO BE SOLVED: To provide an optical sensing device capable of keeping the equipment cost low even when performing multipoint detection using a plurality of reflection type optical sensors.
A pair of light introducing portions and a light deriving portion are provided, and n pieces of light that are introduced from the light introducing portion selectively propagate to the light deriving portion according to the presence or absence of liquid adhering to the sensing portion. (N: a natural number equal to or greater than 2) optical sensors (1), and in particular, each of the light introducing parts and the light leading parts of the plurality of optical sensors is connected to [n-1] relay lights. The optical detector main body is connected to the light introduction part of the start-side photosensor and the light-extraction part of the end-side photosensor in the optical sensor array sequentially connected in series using the fiber (3) and connected in series by the optical fiber for relay. One end of a pair of transmission optical fibers (4a, 4b) extending to the end is connected.
[Selection] Figure 1

Description

本発明は、液面レベル計や液漏れ検出器として用いるに好適な多点検出型の光センシング装置に関する。 The present invention relates to a multi-point detection type optical sensing device suitable for use as a liquid level meter or a liquid leak detector.

液面レベル計や液漏れ検出器におけるセンサの１つとして、反射形光センサが提唱されている。この種の反射形光センサは、液体の有無を検出するセンシング部としてプリズムを用い、そのプリズム面に液体が付着するか否かによって該プリズム面での光の反射率が変化することを利用して上記センシング部（プリズム）に導入した光を透過または反射させ、その反射光が検出されるか否かによって上記液体の有無を検出するように構成される（例えば特許文献１を参照）。 As one of sensors in a liquid level meter and a liquid leak detector, a reflection type optical sensor has been proposed. This type of reflective optical sensor uses a prism as a sensing unit for detecting the presence or absence of liquid, and utilizes the fact that the reflectance of light on the prism surface changes depending on whether or not liquid adheres to the prism surface. Then, the light introduced into the sensing unit (prism) is transmitted or reflected, and the presence or absence of the liquid is detected based on whether or not the reflected light is detected (see, for example, Patent Document 1).

尚、上記反射形光センサは、例えば液面レベル計として用いる場合には監視対象となる貯液槽（容器）等に設置され、また液漏れ検出器として用いる場合には液密に封止された機器内部等に設置される。そしてこれらの反射形光センサは、ＬＥＤ（発光ダイオード）やＬＤ（レーザダイオード）等の発光素子、およびフォトトランジスタ等の受光素子を備えた検出器本体（いわゆるアンプ）に対して、光伝送用の一対の光ファイバを介して光学的に接続して使用される。
特開２００１−１８３２１９号公報 The reflective optical sensor is installed, for example, in a storage tank (container) to be monitored when used as a liquid level meter, and is liquid-tightly sealed when used as a liquid leak detector. Installed inside the equipment. These reflective optical sensors are used for light transmission with respect to a detector body (so-called amplifier) having a light emitting element such as an LED (light emitting diode) or LD (laser diode) and a light receiving element such as a phototransistor. It is used by being optically connected through a pair of optical fibers.
JP 2001-183219 A

ところで複数の貯液槽における各液面レベルを監視する場合、当然のことながら各貯液槽に反射形光センサをそれぞれ設置することが必要である。また液密に封止された設備機器内部における液漏れ監視対象部位が複数箇所ある場合には、これらの各監視対象部位毎に反射形光センサをそれぞれ設置することが必要である。しかしながら複数個の反射形光センサを用いて多点検出を行う場合、各反射形光センサ毎に検出器本体を準備することが必要である。しかもこれらの複数の反射形光センサと、これらの各反射形光センサにそれぞれ対応する複数の検出器本体とを個々に光ファイバを用いて接続することが必要である。これ故、そのシステム構成が大掛かりとなることが否めず、また複数本の光ファイバの敷設に多大な経費と労力とが必要となることが否めない。 By the way, when monitoring each liquid level in a some liquid storage tank, it is necessary to install a reflection type optical sensor in each liquid storage tank as a matter of course. In addition, when there are a plurality of liquid leakage monitoring target parts inside the equipment tightly sealed, it is necessary to install a reflective optical sensor for each of these monitoring target parts. However, when multipoint detection is performed using a plurality of reflection type photosensors, it is necessary to prepare a detector body for each reflection type photosensor. In addition, it is necessary to individually connect the plurality of reflective optical sensors and the plurality of detector bodies respectively corresponding to the reflective optical sensors using optical fibers. Therefore, it cannot be denied that the system configuration becomes large, and it is unavoidable that a large amount of cost and labor are required for laying a plurality of optical fibers.

本発明はこのような事情を考慮してなされたもので、その目的は、液面レベル計や液漏れ検出器として複数の反射形光センサを用いて多点検出を行う場合であっても、その設備コストを安価に抑えることのできる光センシング装置を提供することにある。 The present invention has been made in consideration of such circumstances, and its purpose is to perform multipoint detection using a plurality of reflective optical sensors as a liquid level meter and a liquid leak detector, An object of the present invention is to provide an optical sensing device that can keep the equipment cost low.

上述した目的を達成するべく本発明は、例えば複数の貯液槽（容器）の全てが空になったことを速やかに検出しなければならないような場合には、逆に少なくとも１つの貯液槽での貯液量が確保されていることが確認できれば良いこと、また設備機器の内部における液漏れを複数の反射形光センサを用いて多点検出する場合には、専ら、その１つにおいて液漏れが検出されたとき、これを上記設備機器の異常発生として判定すれば良いことに着目してなされている。 In order to achieve the above-described object, the present invention, for example, when it is necessary to promptly detect that all of the plurality of liquid storage tanks (containers) are empty, conversely, at least one liquid storage tank. It is sufficient that it is possible to confirm that the amount of stored liquid is secured, and when liquid leakage inside the equipment is detected at multiple points using a plurality of reflective optical sensors, the liquid is exclusively used in one of them. It is made paying attention to the fact that when a leak is detected, it may be determined that an abnormality has occurred in the equipment.

そこで本発明に係る光センシング装置は、請求項１に記載するように一対の光導入部と光導出部とを備え、センシング部に付着する液体の有無に応じて上記光導入部から導入された光を選択的に前記光導出部に伝播するｎ個（ｎ：２以上の自然数）の光センサを備えたものであって、特に上記複数の光センサにおける上記各光導入部と光導出部とを［ｎ−１］本の中継用光ファイバを用いて順次直列に連結し、中継用光ファイバにより直列に連結された光センサ列における始端側光センサの光導入部および終端側光センサの光導出部に、光検出器本体まで延設される一対の伝送用光ファイバの一端をそれぞれ連結したことを特徴としている。 Accordingly, the optical sensing device according to the present invention includes a pair of light introducing portions and a light deriving portion as described in claim 1, and is introduced from the light introducing portion according to the presence or absence of liquid adhering to the sensing portion. Comprising n (n: a natural number greater than or equal to 2) photosensors for selectively propagating light to the light deriving unit, and in particular the light introducing units and the light deriving units in the plurality of photosensors, Are sequentially connected in series using [n-1] relay optical fibers, and the light introduction part of the start-side photosensor and the light of the end-side photosensor in the photosensor array connected in series by the relay optical fiber. One end of a pair of transmission optical fibers extending to the photodetector main body is connected to the lead-out portion.

ちなみに前記各光センサは、例えば請求項２に記載するように所定の間隔を隔てて平行に並べて光ファイバからなる光導入部と光導出部とを設け、この光導入部と光導出部にそれぞれ対峙させて上記光導入部と光導出部とを結ぶ反射光路を形成するプリズム体を前記センシング部として設けた構造体として実現される。そして上記プリズム体のプリズム面に付着した液体により該プリズム面での反射率が変化したとき、プリズム体に導入された光を透過させることで前記反射光路を遮断するように構成される。 For example, each of the optical sensors is provided with a light introducing portion and a light deriving portion made of optical fibers arranged in parallel at a predetermined interval as described in claim 2, and the light introducing portion and the light deriving portion are respectively provided. This is realized as a structure in which a prism body that forms a reflected light path that connects the light introduction section and the light extraction section in a confronting manner is provided as the sensing section. When the reflectance on the prism surface is changed by the liquid adhering to the prism surface of the prism body, the reflected light path is blocked by transmitting the light introduced into the prism body.

好ましくは前記中継用光ファイバは、請求項３に記載するように前記光センサ列を形成する複数の光センサにそれぞれ一体化して設けるようにすれば良い。また請求項４に記載するように前記光検出器本体は、前記中継用光ファイバにより直列に連結された光センサ列と対をなして設けるようにすれば良い。
また本発明に係る光センシング装置は、請求項５に記載するように一対の発光素子と受光素子とを備え、センシング部に付着する液体の有無に応じて上記発光素子から放出された光を選択的に前記受光素子に伝播するｎ個（ｎ：２以上の自然数）の光センサを備えたものであって、特に上記複数の光センサの発光素子および受光素子を［ｎ−１］対の中継用信号線を用いてそれぞれ順次直列に連結し、中継用信号線により直列に連結された光センサ列における始端側および終端側の各光センサの発光素子および受光素子に、光検出器本体まで延設される２対の伝送用信号線の各一端をそれぞれ連結したことを特徴としている。 Preferably, the relay optical fiber may be provided integrally with each of a plurality of optical sensors forming the optical sensor array as described in claim 3. According to a fourth aspect of the present invention, the photodetector main body may be provided in a pair with a photosensor array connected in series by the relay optical fiber.
The optical sensing device according to the present invention comprises a pair of light emitting elements and a light receiving element as described in claim 5, and selects light emitted from the light emitting elements according to the presence or absence of liquid adhering to the sensing unit. In particular, there are provided n (n: a natural number greater than or equal to 2) photosensors propagating to the light receiving element, and in particular, [n-1] pairs of relays between the light emitting elements and the light receiving elements of the plurality of photosensors. The optical signal lines are sequentially connected in series with each other, and the light emitting element and the light receiving element of each of the optical sensors on the start side and the end side in the optical sensor array connected in series with the signal line for relay are extended to the photodetector body. Each of the two pairs of transmission signal lines provided is connected to one end.

ちなみに各光センサは、例えば請求項６に記載するように光学的に分離させて並べて発光素子と受光素子とを設け、上記発光素子の発光面と前記受光素子受光面とにそれぞれ対峙させて上記発光素子と受光素子とを結ぶ反射光路を形成するプリズム体を前記センシング部として設けた構造体として実現される。そしてプリズム体のプリズム面に付着した液体により該プリズム面での反射率が変化したとき、プリズム体に導入された光を透過させることで前記反射光路を遮断するように構成される。この場合においても前記光検出器本体は、前記中継用信号線により直列に連結された光センサ列と対をなして設ける要にすれば良い。 Incidentally, each optical sensor is provided with a light emitting element and a light receiving element that are optically separated and arranged as described in claim 6, for example, and the light emitting surface of the light emitting element and the light receiving element light receiving surface are opposed to each other. This is realized as a structure in which a prism body that forms a reflected light path connecting a light emitting element and a light receiving element is provided as the sensing unit. When the reflectance on the prism surface changes due to the liquid adhering to the prism surface of the prism body, the reflected light path is blocked by transmitting the light introduced into the prism body. Even in this case, the photodetector main body may be provided in a pair with the optical sensor array connected in series by the relay signal line.

このような構成の光センシング装置によれば、複数の光センサが中継用光ファイバ／中継用信号線を介して直列に接続されているので、この光センサ列に対する光検出器本体への光学的／電気的な接続については一対の伝送用光ファイバまたは２対の伝送用信号線を用いるだけで簡易に行い得る。しかも複数の光センサを直列接続した光センサ列に対して１個の光検出器本体を設けるだけで良い。従って複数の光センサを用いて多点検出を行う場合、光検出器本体との間に敷設する伝送用光ファイバ／伝送用信号線の本数を減らすと共にその敷設コストを下げることができ、また光センサの数に比較して光検出器本体の数を少なくすることができるので、この点でもその設備コストを低減し得る等の効果が奏せられる。 According to the optical sensing device having such a configuration, since the plurality of optical sensors are connected in series via the relay optical fiber / relay signal line, the optical sensor to the optical detector body with respect to the optical sensor array is optically connected. / Electrical connection can be performed simply by using a pair of transmission optical fibers or two pairs of transmission signal lines. In addition, it is only necessary to provide one photodetector main body for an optical sensor array in which a plurality of optical sensors are connected in series. Therefore, when multipoint detection is performed using a plurality of optical sensors, the number of transmission optical fibers / transmission signal lines to be laid between the optical detector body and the laying cost can be reduced. Since the number of photodetector main bodies can be reduced as compared with the number of sensors, there is an effect that the equipment cost can be reduced also in this respect.

また複数の光センサに対して予め中継用光ファイバをそれぞれ一体化しておけば、例えば液漏れ検出対象とする設備機器に対して光センサを容易に設置する（組み付ける）ことができるので、その取り扱いが容易である等の効果が奏せられる。 In addition, if the optical fibers for relay are integrated with each of a plurality of optical sensors in advance, for example, the optical sensor can be easily installed (assembled) on the equipment to be detected as a liquid leak. The effect that it is easy is produced.

以下、図面を参照して本発明の一実施形態に係る光センシング装置について説明する。
図１および図２は本発明の第１の実施形態に係る光センシング装置の要部概略構成と、その使用形態をそれぞれ示すもので、１ａ,１ｂはそれぞれ光センサである。尚、ここでは２つの光センサ１ａ,１ｂを直列接続して用いられる光センシング装置を例に説明するが、一般的には３本以上の光センサ１を直列に接続して用いる場合にも同様に適用することができる。 Hereinafter, an optical sensing device according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 and FIG. 2 respectively show a schematic configuration of a main part of the optical sensing device according to the first embodiment of the present invention and a usage pattern thereof. Reference numerals 1a and 1b denote optical sensors, respectively. Here, an optical sensing device in which two optical sensors 1a and 1b are connected in series will be described as an example, but generally the same applies when three or more optical sensors 1 are connected in series. Can be applied to.

尚、図１は複数（２つ）の貯液槽Ａ,Ｂにそれぞれ貯留される液体（例えば水や薬液）の貯留量を監視するべく、上記各貯液槽Ａ,Ｂにそれぞれ光センサ１ａ,１ｂを設置する例を示している。また図２は各種の設備機器における、例えば水濡れが厳禁された２つの密閉空間Ｘ,Ｙにおける外部からの水の進入（水漏れ）を監視するべく、上記密閉空間Ｘ,Ｙにそれぞれ光センサ１ａ,１ｂを設置する例を示している。 FIG. 1 shows an optical sensor 1a for each of the liquid storage tanks A and B in order to monitor the amount of liquid (for example, water or chemicals) stored in a plurality (two) of liquid storage tanks A and B, respectively. , 1b is shown. Further, FIG. 2 shows an optical sensor in each of the sealed spaces X and Y in order to monitor the ingress (water leakage) of water from the outside in various sealed equipments X and Y, for example, which are strictly prohibited from being wet. The example which installs 1a and 1b is shown.

さて上記光センサ１（１ａ,１ｂ）は、基本的には図３にその概略的な断面構造を示すように、光導入部および光導出部をなす一対の光ファイバ１１,１２を所定の間隔を隔てて平行に並べて設けると共に、これらの光ファイバ（光導入部および光導出部）１１,１２の各端面に対峙させて上記光導入部と光導出部とを結ぶ反射光路を形成するプリズム体１３をセンシング部として設けたものからなる。厳密には上記各光ファイバ１１,１２の各端面がプリズム体１３に対する光導入部および光導出部となる。ちなみに前記一対の光ファイバ１１,１２を保持すると共に、その先端部にプリズム体１３を形成したセンサ本体１４は、例えばＰＦＡ（ぺルフルオロ・アルコキシ・フッ素樹脂）等の透明な合成樹脂からなる。また上記プリズム体１３は、例えばその外周面を４５°の斜面とした円錐体からなる。特にこの例では、プリズム体１３の先端部に階段状の液溜め部５が設けられている。この液溜め部５は、プリズム体１３の斜面（プリズム面）に付着した液体をその周面に滴状に溜めることで上記斜面（プリズム面）からの液体の流れ出しを早め、いわゆる水切れを良くする役割を担う。 Now, the optical sensor 1 (1a, 1b) basically has a pair of optical fibers 11, 12 forming a light introducing part and a light leading part as shown in FIG. And a prism body that forms a reflected light path that connects the light introducing portion and the light guiding portion so as to face each end face of these optical fibers (light introducing portion and light guiding portion) 11 and 12. 13 is provided as a sensing unit. Strictly speaking, each end face of each of the optical fibers 11 and 12 serves as a light introducing part and a light leading part for the prism body 13. Incidentally, the sensor main body 14 which holds the pair of optical fibers 11 and 12 and has the prism body 13 formed at the tip thereof is made of a transparent synthetic resin such as PFA (perfluoroalkoxy / fluorine resin). The prism body 13 is formed of, for example, a cone whose outer peripheral surface is a 45 ° slope. In particular, in this example, a step-like liquid reservoir 5 is provided at the tip of the prism body 13. The liquid reservoir 5 accumulates the liquid adhering to the inclined surface (prism surface) of the prism body 13 in the form of droplets on its peripheral surface, thereby speeding up the flow of the liquid from the inclined surface (prism surface) and improving the so-called water drainage. Take a role.

このような構造の光センサ１は、前述した特許文献１にも詳しく解説されるようにプリズム体１３が空気中に晒されている場合には、プリズム体１３の構成素材（例えば上述したＰＦＡ）の屈折率と空気の屈折率との違いによりそのプリズム面にて光の反射作用を呈し、前記光導入部（光ファイバ１１）からプリズム体１３に導入された光を反射して光導出部（光ファイバ１２）に導く反射光路を形成する。そしてプリズム体１３が液体（例えば水）に浸漬したとき、或いはそのプリズム面に液体が付着したとき、その液体の屈折率とプリズム体１３の屈折率とがほぼ等しくなることから、前述した光導入部（光ファイバ１１）から導入された光を反射することなく透過し、これによって前記反射光路を消滅（遮断）する作用を呈する。従ってこのような構造の反射形光センサ１によれば、光導入部（光ファイバ１１）から導入した光が光導出部（光ファイバ１２）から検出されるか否かによって、前記プリズム体１３が液体中に浸漬しているか否か、或いはそのプリズム面に液体が付着しているか否かを検出することが可能となる。 As described in detail in Patent Document 1 described above, the optical sensor 1 having such a structure has a configuration material (for example, the above-described PFA) of the prism body 13 when the prism body 13 is exposed to the air. Due to the difference between the refractive index of air and the refractive index of air, the prism surface exhibits light reflecting action, and the light introduced into the prism body 13 from the light introducing part (optical fiber 11) is reflected to produce a light deriving part ( A reflection optical path leading to the optical fiber 12) is formed. When the prism body 13 is immersed in a liquid (for example, water), or when the liquid adheres to the prism surface, the refractive index of the liquid and the refractive index of the prism body 13 are almost equal. The light introduced from the part (optical fiber 11) is transmitted without being reflected, thereby exhibiting the action of extinguishing (blocking) the reflected light path. Therefore, according to the reflection type optical sensor 1 having such a structure, the prism body 13 is formed depending on whether or not the light introduced from the light introducing part (optical fiber 11) is detected from the light deriving part (optical fiber 12). It is possible to detect whether the liquid is immersed in the liquid or whether the liquid is attached to the prism surface.

さてこのような反射形光センサ１を複数個（この例では２個）用いて構成される光センシング装置は、図１および図２にそれぞれ示すように光センサ１ａ,１ｂの光導入部と光導出部とを中継用光ファイバ３を介して直列に接続して光センサ列を形成すると共に、上記光センサ１ａの光導入部、および光センサ１ｂの光導出部に一対の伝送用光ファイバ４ａ,４ｂをそれぞれ接続して構成される。この一対の伝送用光ファイバ４ａ,４ｂは、ＬＥＤ（発光ダイオード）やＬＤ（レーザダイオード）等の発光素子５ａ、およびフォトトランジスタ等の受光素子５ｂを備えた検出器本体（いわゆるアンプ）５の設置場所まで導かれる長尺のものからなる。そして上記検出器本体５の光出力端子および受光端子にそれぞれ光コネクタを介して接続される。 Now, an optical sensing device constituted by using a plurality of such reflection type optical sensors 1 (two in this example) has a light introduction part and light of the optical sensors 1a and 1b as shown in FIGS. 1 and 2, respectively. The lead-out part is connected in series via the relay optical fiber 3 to form an optical sensor array, and a pair of transmission optical fibers 4a are connected to the light introduction part of the optical sensor 1a and the light lead-out part of the optical sensor 1b. , 4b are connected to each other. The pair of transmission optical fibers 4a and 4b are provided with a detector body (so-called amplifier) 5 including a light emitting element 5a such as an LED (light emitting diode) or LD (laser diode) and a light receiving element 5b such as a phototransistor. It consists of a long one that leads to the place. The detector main body 5 is connected to the light output terminal and the light receiving terminal via optical connectors, respectively.

尚、光コネクタについては特開２００４−２９４９０６号公報等に開示されるような、光結合すべき２本の光ファイバの各端面を同軸に位置合わせして当接させ、この状態で上記２本の光ファイバを一体に結合保持する構造のものであれば十分である。
また前述した中継用光ファイバ３については、光センシング装置としての用途とその仕様が予め定まっているような場合には、所定の長さの光ファイバとして光センサ１ａ,１ｂ間に固定的に取り付けておくようにすれば良い。また光センサ１ａに一体に組み付けられて光導出部をなす光ファイバ１２と、光センサ１ｂに一体に組み付けられて光導入部をなす光ファイバ１１とを上述した光コネクタを用いて光学的に連結することで、等価的に中継用光ファイバ３を実現することも可能である。 As for the optical connector, as disclosed in Japanese Patent Application Laid-Open No. 2004-294906, etc., the end faces of the two optical fibers to be optically coupled are aligned and brought into contact with each other. It is sufficient to have a structure in which the optical fibers are integrally coupled and held.
In addition, the optical fiber 3 for relay described above is fixedly attached between the optical sensors 1a and 1b as an optical fiber of a predetermined length when the use as an optical sensing device and its specifications are predetermined. You should keep it. In addition, the optical fiber 12 that is integrated with the optical sensor 1a to form a light lead-out portion and the optical fiber 11 that is integrated with the optical sensor 1b to form a light introducing portion are optically coupled using the optical connector described above. Thus, it is possible to realize the relay optical fiber 3 equivalently.

かくして上述した如く構成された光センシング装置によれば、複数（２個）の光センサ１ａ,１ｂが中継用光ファイバ３を介して直列に接続されて光センサ列を構成しているので、この光センサ列への光の入出力に供する一対の伝送用光ファイバ４ａ,４ｂを光検出器本体５の設置場所まで延設し、上記伝送用光ファイバ４ａ,４ｂを光コネクタを用いて光検出器本体５に接続（連結）するだけで、簡易にその敷設作業を行い得る。しかも複数（２個）の光センサ１ａ,１ｂを用いて多点検出するにも拘わらず、光検出器本体５との間に一対の伝送用光ファイバ４ａ,４ｂを敷設するだけで良い。また複数の光センサ１ａ,１ｂを直列接続した光センサ列に対して１個の光検出器本体５を設けるだけで良いので、設備コストの高い光検出器本体５の必要個数を減らすことができる。従って複数の光センサ１ａ,１ｂを用いて多点検出を行うといえども、従来のように複数の光センサ１ａ,１ｂのそれぞれに対応した光検出器本体５を準備し、またこれらの間で個別に伝送用光ファイバ４ａ,４ｂを敷設する必要がないので、その設備コストを低減し得る等の効果が奏せられる。 Thus, according to the optical sensing device configured as described above, a plurality (two) of optical sensors 1a and 1b are connected in series via the relay optical fiber 3 to form an optical sensor array. A pair of transmission optical fibers 4a and 4b used for input / output of light to / from the optical sensor array are extended to the installation location of the photodetector body 5, and the transmission optical fibers 4a and 4b are optically detected using an optical connector. By simply connecting (connecting) to the main body 5, the installation work can be easily performed. Moreover, it is only necessary to lay a pair of transmission optical fibers 4a and 4b between the optical detector main body 5 in spite of multipoint detection using a plurality (two) of optical sensors 1a and 1b. Further, since only one photodetector main body 5 needs to be provided for a photosensor array in which a plurality of photosensors 1a and 1b are connected in series, the required number of photodetector main bodies 5 with high equipment costs can be reduced. . Therefore, even if multipoint detection is performed using a plurality of photosensors 1a and 1b, a photodetector main body 5 corresponding to each of the plurality of photosensors 1a and 1b is prepared as in the prior art. Since it is not necessary to separately lay the transmission optical fibers 4a and 4b, there is an effect that the equipment cost can be reduced.

また前述したように複数の光センサ１ａ,１ｂに対して、予め液漏れ検出対象とする設備機器の仕様に合わせた所定の長さの中継用光ファイバ３をそれぞれ一体化しておけば、上記設備機器に対して上記光センサ１ａ,１ｂを容易に設置する（組み付ける）ことが可能であり、またその設置現場において上記光センサ１ａ,１ｂを直列に連結する必要もないので、その取り扱いが非常に容易である。特に３個以上の光センサを直列に接続して多点検出を行うような場合、その効果が大きい。 As described above, if the plurality of optical sensors 1a and 1b are integrated in advance with the optical fiber for relay 3 having a predetermined length according to the specifications of the equipment to be detected for liquid leakage, the above equipment is provided. It is possible to easily install (assemble) the optical sensors 1a and 1b to the device, and it is not necessary to connect the optical sensors 1a and 1b in series at the installation site. Easy. In particular, when multipoint detection is performed by connecting three or more optical sensors in series, the effect is great.

次に本発明の第２の実施形態について説明する。この第２の実施形態に係る光センシング装置は、複数の光センサ２１ａ,２１ｂにそれぞれ対をなす発光素子２２と受光素子２３とを組み込み、これらの各光センサ２１ａ,２１ｂにおける発光素子２２および受光素子２３をそれぞれ電気的に直列接続して構成される。この場合においても、３本以上の光センサ２１（２１ａ,２１ｂ,〜２１ｎ）を直列に接続して用いる場合にも同様に適用することができることは言うまでもない。 Next, a second embodiment of the present invention will be described. The optical sensing device according to the second embodiment incorporates a pair of light emitting element 22 and light receiving element 23 in each of a plurality of optical sensors 21a and 21b, and the light emitting element 22 and the light receiving element in each of these optical sensors 21a and 21b. The elements 23 are each electrically connected in series. In this case, it goes without saying that the present invention can be similarly applied to a case where three or more optical sensors 21 (21a, 21b, to 21n) are connected in series.

ちなみに上記各光センサ２１ａ,２１ｂにそれぞれ設けられる発光素子２２および受光素子２２は、図４に示すようにその発光面と受光面の向きを揃え、且つ光学的に分離されて所定の間隔を隔てて並べて前述したプリズム体１３に対峙させて設けられる。そして発光素子２２から射出される光を前述したプリズム体１３が形成する反射光路を介して受光素子２３に導くように構成される。 Incidentally, the light emitting element 22 and the light receiving element 22 provided in each of the optical sensors 21a and 21b are aligned with each other as shown in FIG. 4 and optically separated with a predetermined interval therebetween. And arranged opposite to the prism body 13 described above. And it is comprised so that the light inject | emitted from the light emitting element 22 may be guide | induced to the light receiving element 23 through the reflective optical path which the prism body 13 mentioned above forms.

そしてこのような反射形光センサ２１を複数個（この例では２個）用いて構成される光センシング装置は、図４に示すように各光センサ２１ａ,２１ｂにそれぞれ設けられた発光素子２２および受光素子２３を、それぞれ中継用信号線２４,２５を介して順次直列に接続して光センサ列を形成すると共に、上記各光センサ１ａ,１ｂにおける発光素子２２および受光素子２３を２対の伝送用信号線２６ａ,２６ｂ,２７ａ,２７ｂをそれぞれ接続して構成される。これらの伝送用信号線２６ａ,２６ｂ,２７ａ,２７ｂは、ＬＥＤ駆動電源および増幅器を備えた検出器本体（いわゆるアンプ）５の設置場所まで導かれる長尺の信号ケーブル（電線）、具体的には４芯の信号ケーブルとして実現される。そして上記伝送用信号線２６ａ,２６ｂ,２７ａ,２７ｂは、検出器本体５の信号出力端子および信号検出端子にそれぞれコネクタを介して電気的に接続される。 An optical sensing device configured by using a plurality (two in this example) of such reflection type optical sensors 21 includes a light emitting element 22 provided in each of the optical sensors 21a and 21b, as shown in FIG. The light receiving elements 23 are sequentially connected in series via relay signal lines 24 and 25 to form an optical sensor array, and the light emitting elements 22 and the light receiving elements 23 in the optical sensors 1a and 1b are transmitted in two pairs. The signal lines 26a, 26b, 27a, 27b are connected to each other. These transmission signal lines 26a, 26b, 27a, and 27b are long signal cables (electric wires) that are led to the installation location of the detector main body (so-called amplifier) 5 having an LED driving power source and an amplifier, specifically, This is realized as a 4-core signal cable. The transmission signal lines 26a, 26b, 27a, 27b are electrically connected to the signal output terminal and the signal detection terminal of the detector body 5 through connectors, respectively.

このように構成された光センシング装置によれば、前述した第１の実施形態と同様に発光素子２２および受光素子２３をそれぞれ中継用信号線２４,２５を介して直列に接続した光センサ列に対して、検出器本体５との間で２対の伝送用信号線（４芯の信号ケーブル）２６ａ,２６ｂ,２７ａ,２７ｂを用いて電気的に接続するだけで良いので、その敷設作業の簡易化を図ると共に、設備コストの低廉化を図ることが可能となる。しかも光センサ列を構成する複数の光センサ２１については、例えば予め中継用信号線２４,２５を用いてその発光素子２２および受光素子２３をそれぞれ直列に接続しておけば良いので、光センサ列自体を単品部品として取り扱うことも容易である等の効果が奏せられる。 According to the optical sensing device configured in this manner, the light emitting element 22 and the light receiving element 23 are connected in series via the relay signal lines 24 and 25, respectively, as in the first embodiment described above. On the other hand, it is only necessary to electrically connect the detector main body 5 using two pairs of transmission signal lines (four-core signal cables) 26a, 26b, 27a, 27b. It is possible to reduce the equipment cost. In addition, for the plurality of optical sensors 21 constituting the optical sensor array, for example, the light emitting element 22 and the light receiving element 23 may be connected in series using the relay signal lines 24 and 25 in advance. The effect that it is easy to handle itself as a single-piece component is exhibited.

尚、本発明は上述した実施形態に限定されるものではない。例えば光センサ１自体の構成は種々変形可能なことは言うまでもなく、構造や大きさの異なる複数種の反射形光センサを直列に接続して用いる場合にも同様に適用可能である。またここではプリズム体１３への液体の付着により反射光路を遮断する構造の光センサを例に説明したが、逆にプリズム体１３に液体が付着したとき、光導入部と光導出部とを結ぶ光路を形成するように光センサを構成することも可能である。 The present invention is not limited to the embodiment described above. For example, it goes without saying that the configuration of the optical sensor 1 itself can be variously modified, and is similarly applicable to a case where a plurality of types of reflective optical sensors having different structures and sizes are connected in series. Further, here, the optical sensor having a structure in which the reflected light path is blocked by the adhesion of the liquid to the prism body 13 has been described as an example, but conversely, when the liquid adheres to the prism body 13, the light introduction section and the light extraction section are connected. It is also possible to configure the optical sensor so as to form an optical path.

また中継用光ファイバ３を介して直列に接続された複数の光ファイバ１の始端側に発光素子を組み込むと共に、その終端側に受光素子を組み込み、これらの発光素子および受光素子と検出器本体５との間を４芯の信号ケーブルを用いて電気的に接続するように構成することもできる。その他、本発明はその要旨を逸脱しない範囲で種々変形して実施することができる。 In addition, a light emitting element is incorporated at the start end side of a plurality of optical fibers 1 connected in series via the relay optical fiber 3, and a light receiving element is incorporated at the end side thereof, and these light emitting element, light receiving element, and detector body 5 are incorporated. Can be electrically connected to each other using a 4-core signal cable. In addition, the present invention can be variously modified and implemented without departing from the scope of the invention.

本発明の第１の実施形態に係る光センシング装置の概略構成と、その使用形態を示す図。The figure which shows schematic structure of the optical sensing apparatus which concerns on the 1st Embodiment of this invention, and its usage form. 本発明に係る光センシング装置の別の使用形態を示す図。The figure which shows another usage pattern of the optical sensing apparatus which concerns on this invention. 光センシング装置に用いられる光センサの一例を示す概略構成図。The schematic block diagram which shows an example of the optical sensor used for an optical sensing apparatus. 本発明の第２の実施形態に係る光センシング装置の概略構成を示す図。The figure which shows schematic structure of the optical sensing apparatus which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

１（１ａ,１ｂ）光センサ
３中継用光ファイバ
４ａ,４ｂ伝送用光ファイバ
５光検出器本体（アンプ）
１１光導入部（光ファイバ）
１２光導出部（光ファイバ）
１３プリズム体
２１（２１ａ,２１ｂ）光センサ
２２発光素子
２３受光素子
２４,２５中継用信号線
２６ａ,２６ｂ,２７ａ,２７ｂ伝送用信号線 1 (1a, 1b) Optical sensor 3 Relay optical fiber 4a, 4b Transmission optical fiber 5 Photodetector body (amplifier)
11 Light introduction part (optical fiber)
12 Light outlet (optical fiber)
13 Prism body 21 (21a, 21b) Optical sensor 22 Light emitting element 23 Light receiving element 24, 25 Signal line for relay 26a, 26b, 27a, 27b Signal line for transmission

Claims

A pair of light introducing portions and a light deriving portion are provided, and n light beams (n: 2) that selectively propagate light introduced from the light introducing portion to the light deriving portion according to the presence or absence of liquid adhering to the sensing portion. A natural sensor)
[N-1] relay optical fibers in which the light introduction part and the light lead-out part of these optical sensors are sequentially connected in series;
One end is connected to the light introduction part of the start-end side optical sensor and the light lead-out part of the end-side photosensor in the optical sensor array connected in series by the relay optical fiber, and the other end is extended to the photodetector main body. An optical sensing device comprising: a pair of transmission optical fibers.

The optical sensor includes a prism body that is provided opposite to a light introducing portion and a light deriving portion that are arranged in parallel at a predetermined interval to form a reflected light path that connects the light introducing portion and the light deriving portion. The sensing unit,
2. The optical sensing device according to claim 1, wherein the prism body is configured to block the reflected light path by changing a reflectance on the prism surface by liquid adhering to the prism surface. 3.

The optical sensing device according to claim 1, wherein the relay optical fiber is provided integrally with a plurality of optical sensors forming the optical sensor array.

The optical sensing device according to claim 1, wherein the photodetector main body is provided in a pair with a photosensor array connected in series by the relay optical fiber.

A pair of light emitting elements and light receiving elements, and n light (n: a natural number of 2 or more) that selectively propagates light emitted from the light emitting elements to the light receiving elements in accordance with the presence or absence of liquid adhering to the sensing unit. With a light sensor
[N-1] pairs of relay signal lines in which the light emitting elements and the light receiving elements of these optical sensors are sequentially connected in series,
One end is connected to the light emitting element and the light receiving element of each of the photosensors on the start end side and the end end in the photosensor array connected in series by the relay signal line, and the other end side extends to the photodetector main body 2. An optical sensing device comprising a pair of transmission signal lines.

The light sensor includes a prism body that is provided to oppose the light-emitting surface and the light-receiving surface of the light-emitting element and the light-receiving element that are optically separated and arranged to form a reflected light path that connects the light-emitting element and the light-receiving element. The sensing unit,
The optical sensing device according to claim 5, wherein the prism body is configured to block the reflected light path by changing a reflectance on the prism surface by liquid adhering to the prism surface.

The optical sensing device according to claim 5, wherein the photodetector main body is provided in a pair with an optical sensor array connected in series by the relay signal line.