JPS62222124A - Liquid level detector - Google Patents
Liquid level detectorInfo
- Publication number
- JPS62222124A JPS62222124A JP6552886A JP6552886A JPS62222124A JP S62222124 A JPS62222124 A JP S62222124A JP 6552886 A JP6552886 A JP 6552886A JP 6552886 A JP6552886 A JP 6552886A JP S62222124 A JPS62222124 A JP S62222124A
- Authority
- JP
- Japan
- Prior art keywords
- detected
- liquid level
- liquid
- light
- lens body
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000007788 liquid Substances 0.000 title claims abstract description 142
- 230000003287 optical effect Effects 0.000 abstract description 20
- 238000001514 detection method Methods 0.000 abstract description 5
- 238000005406 washing Methods 0.000 abstract 2
- 239000000356 contaminant Substances 0.000 abstract 1
- 239000013307 optical fiber Substances 0.000 description 39
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 230000002457 bidirectional effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
Landscapes
- Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
Abstract
Description
【発明の詳細な説明】
「産業上の利用分野」
この発明は、液面位置を検出する液面検出器に関するも
のである。DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a liquid level detector that detects the position of a liquid level.
「従来の技術」
被検出液面位置の検出を光学的に行なう液面検出器が使
用されている。"Prior Art" Liquid level detectors are used that optically detect the position of the liquid level to be detected.
第2図の要部の構成を示すのは、従来使用されているこ
の種の液面検出器であり、被検出液面11に第1のプリ
ズム面13を対向させてプリズム12が配設される。プ
リズム12の第2及び第3のプリズム面14及び15に
それぞれ対向して、発光素子16及び受光素子17が配
設される。The structure of the main part shown in FIG. 2 is a conventionally used liquid level detector of this type, in which a prism 12 is disposed with a first prism surface 13 facing the liquid level 11 to be detected. Ru. A light emitting element 16 and a light receiving element 17 are arranged opposite to the second and third prism surfaces 14 and 15 of the prism 12, respectively.
被検出液面11がプリズム12の第1のプリズム面13
に接触せず、第1のプリズム面13が空気層に接触して
いる状態では、発光素子16からの入射光はプリズム1
2の第1のプリズム面13で全反射して、第2図に実線
で示す光路をとって受光素子17で受光される。被検出
液面11が上昇してプリズム12の第1のプリズム面1
3と接触すると、第1のプリズム面13位置での入射光
に対する屈折率が変化し、発光素子16からの入射光は
、第2図に点線で示す光路をとって被検出液内に入射さ
れ、受光素子17には到達しない。The liquid level 11 to be detected is the first prism surface 13 of the prism 12
When the first prism surface 13 is in contact with the air layer without contacting the prism 1, the incident light from the light emitting element 16 is transmitted to the prism
The light is totally reflected by the first prism surface 13 of FIG. The liquid level 11 to be detected rises and the first prism surface 1 of the prism 12
3, the refractive index for the incident light at the position of the first prism surface 13 changes, and the incident light from the light emitting element 16 enters the liquid to be detected along the optical path shown by the dotted line in FIG. , does not reach the light receiving element 17.
従って、受光素子17での受光の有無によって被検出液
がプリズム12の第1のプリズム面13の基準位置1o
に達しているか否かが検出される。Therefore, depending on whether or not light is received by the light receiving element 17, the liquid to be detected is placed at the reference position 1o on the first prism surface 13 of the prism 12.
It is detected whether or not it has been reached.
第3図に同一部分に対して同一符号を付して要部の構成
を示すのは、従来使用されている液面検出器の他の例で
あり、プリズム12は第2及び第3のプリズム面14.
15を被検出液面11に対向させて配設される。この場
合はプリズム12の第1のプリズム面12に対して光フ
ァイバ20゜21がそれぞれ対向して配設され、それぞ
れの光ファイバ20.21の延長の端面に対して発光素
子16及び受光素子17が近接対向して配設されている
。第3図に示す例では、被検出液面11が基準位’fl
loに達しない状態では、プリズム12の第2及び第3
のプリズム面14.15は空気と接しているために、発
光素子16からの入射光は光ファイバ20を通り、第3
図に実線で示した光路のように第2及び第3のプリズム
面14.&び15で全反射して、光ファイバ21に入射
し、受光素子17で受光される。In FIG. 3, the same reference numerals are assigned to the same parts to show the structure of the main parts. This is another example of a conventionally used liquid level detector, and the prism 12 is a second and third prism. Surface 14.
15 is arranged to face the liquid surface 11 to be detected. In this case, the optical fibers 20 and 21 are arranged to face the first prism surface 12 of the prism 12, respectively, and the light emitting element 16 and the light receiving element 17 are arranged to face the extended end surfaces of the respective optical fibers 20 and 21. are arranged close to each other and facing each other. In the example shown in FIG. 3, the detected liquid level 11 is at the reference position 'fl
When lo is not reached, the second and third prisms 12
Since the prism surfaces 14 and 15 of are in contact with air, the incident light from the light emitting element 16 passes through the optical fiber 20 and enters the third
As shown in the optical path indicated by a solid line in the figure, the second and third prism surfaces 14. The light is totally reflected by the & 15, enters the optical fiber 21, and is received by the light receiving element 17.
被検出液面11が上界して基準位置10に達すると、プ
リズム12の第2及び第3のプリズム面14及び15の
一部が被検出液に浸される。このために入射光に対する
屈折率が変化し、発光素子16からの入射光は第2のプ
リズム面14で全反射せずに被検出液内に入射する。従
って、被検出液面11が基準位置j!Oに達すると、受
光素子17での受光が行なわれず、被検出液が基準位”
flR。When the detected liquid level 11 rises and reaches the reference position 10, parts of the second and third prism surfaces 14 and 15 of the prism 12 are immersed in the detected liquid. Therefore, the refractive index with respect to the incident light changes, and the incident light from the light emitting element 16 enters the liquid to be detected without being totally reflected on the second prism surface 14. Therefore, the detected liquid level 11 is at the reference position j! When the temperature reaches O, the light receiving element 17 does not receive light and the liquid to be detected is at the reference level.
flR.
に達したか否かの検出が行なわれる。Detection is made as to whether or not this has been reached.
「発明が解決しようとする問題点」
従来使用されている液面検出器では、前述のように液面
検出器を構成する光学的部品であるプリズムに被検出液
面が達することによる入射光の光路における光の屈折率
の変化による受光素子17での受光の有無を検出してい
る。“Problems to be Solved by the Invention” In conventional liquid level detectors, as mentioned above, the incident light is caused by the liquid level to be detected reaching the prism, which is an optical component that constitutes the liquid level detector. The presence or absence of light reception by the light receiving element 17 is detected based on changes in the refractive index of light in the optical path.
このため検出時に、光学的部品が被検出液に浸されるこ
とがあり、例えば被検出液が腐蝕性の強い液体であると
受光素子17が腐蝕されてしまうので、その液面検出は
不可能であった。Therefore, during detection, optical components may be immersed in the liquid to be detected. For example, if the liquid to be detected is a highly corrosive liquid, the light receiving element 17 will be corroded, making it impossible to detect the liquid level. Met.
また、被検出液が腐蝕性の強いものでなくても、光学的
部品が被検出液に浸されるので、その汚れを除去するた
めに、定期的に光学的部品に対して洗滌を行なうなどの
作業が必要であった。In addition, even if the liquid to be detected is not highly corrosive, the optical parts will be immersed in the liquid to be detected, so it is necessary to periodically wash the optical parts to remove the dirt. work was required.
さらに、従来使用されている液面検出器では、液面が基
準位置に存在するか否かを判定することが出来るのみで
あり、被検出液面位置の定量的な検出は全く行なうこと
が出来ない。Furthermore, conventionally used liquid level detectors can only determine whether the liquid level is at the reference position or not, and cannot quantitatively detect the liquid level position to be detected at all. do not have.
この発明は、従来使用されている液面検出器の現状に濫
みてなされたものであり、その目的は腐蝕性の強い被検
出液の液面検出も可能であり、液面検出器の光学的部品
に対する定期的な洗滌作業が不用であり、必要に応じて
被検出液の液面レベルの定量的検出をも行なわせること
が出来る液面検出器を提供することにある。This invention was made in view of the current state of conventional liquid level detectors, and its purpose is to enable liquid level detection of highly corrosive liquids to be detected. It is an object of the present invention to provide a liquid level detector that does not require periodic cleaning of parts and can also perform quantitative detection of the liquid level of a liquid to be detected if necessary.
「発明の構成」
この発明では少なくとも一部を被検出液面上に位置させ
て保持筒体が配され、この保持筒体内に一方の鏡面を被
検出液面に対向させてレンズ体が取り付けられる。この
レンズ体の他方の鏡面に対向して入射光導入端部及び出
射光導出端部が設けられ、これらの入射光導入端部及び
出射光導出端部にはそれぞれ入射光源及び受光素子が接
続される。"Structure of the Invention" In the present invention, a holding cylinder is disposed with at least a portion thereof positioned above the liquid surface to be detected, and a lens body is attached within the holding cylinder with one mirror surface facing the liquid surface to be detected. . An incident light introduction end and an output light guide end are provided opposite to the other mirror surface of the lens body, and an incident light source and a light receiving element are connected to the incident light introduction end and the output light guide end, respectively. Ru.
この発明では入射光導入端部からの入射光は基準位置に
ある被検出液面上に焦点を結び、その被検出液面で反射
して受光素子でほぼ反射全光量が検出され、被検出液面
が所定値以上となると、保持筒内においてレンズ体の一
方の鏡面と被検出液面間に密封空間が形成されるように
構成される。In this invention, the incident light from the incident light introduction end is focused on the liquid surface to be detected at the reference position, is reflected by the liquid surface to be detected, and almost the total amount of reflected light is detected by the light receiving element. When the surface reaches a predetermined value or more, a sealed space is formed in the holding cylinder between one mirror surface of the lens body and the liquid surface to be detected.
従って、被検出液面が所定値以上になると、保持筒内で
レンズ体の一方の鏡面と被検出液面間に密封空間が形成
され、被検出液面位置がそれ以上上昇せず、レンズ体が
被検出液に触れることがない。このためにレンズ体の汚
れ取りや、定期的な洗滌作業が必要なく、保守が容易と
なり、腐蝕性の強い被検出液の検出も行なうことが出来
る。またレンズ体として凸レンズを使用する場合には被
検出液面の位置を定量的に測定することも可能である。Therefore, when the liquid level to be detected exceeds a predetermined value, a sealed space is formed between one mirror surface of the lens body and the liquid level to be detected in the holding cylinder, and the liquid level to be detected does not rise any further, and the lens body does not come into contact with the liquid to be detected. Therefore, there is no need to remove dirt from the lens body or to periodically wash the lens body, making maintenance easier, and it is also possible to detect a highly corrosive liquid to be detected. Furthermore, when a convex lens is used as the lens body, it is also possible to quantitatively measure the position of the liquid surface to be detected.
「実施例」
以下、この考案の液面検出器をその実施例に基づき、図
面を使用して詳細に説明する。"Example" Hereinafter, the liquid level detector of this invention will be described in detail based on an example using the drawings.
第1図に要部の構成を示すのは、この考案の液面検出器
の第1の実施例であり、少なくとも一部を被検出液面上
に位置させて保持筒体が配設される。FIG. 1 shows the configuration of the main parts of the first embodiment of the liquid level detector of this invention, in which a holding cylinder is disposed with at least a part of it above the liquid surface to be detected. .
第1の実施例においては、はぼ円筒状の保持筒体10が
設けられ、この保持筒体10が被検出液が充填されるタ
ンク22に対して固定具23により固定して取り付けら
れている。第1の実施例は、保持筒体10の端面が被検
出液面11の液面上にあると、被検出液面11は基準位
置10にあるように構成されている。In the first embodiment, a hollow cylindrical holding cylinder 10 is provided, and this holding cylinder 10 is fixedly attached by a fixture 23 to a tank 22 filled with the liquid to be detected. . The first embodiment is configured such that when the end surface of the holding cylinder 10 is on the liquid level of the liquid level 11 to be detected, the liquid level 11 to be detected is at the reference position 10.
保持筒体lO内に一方の鏡面を被検出液面11に対向さ
せて、レンズ体25が取り付けられる。A lens body 25 is attached within the holding cylinder IO with one mirror surface facing the liquid surface 11 to be detected.
第1の実施例では、保持筒体10内にレンズ体25とし
て屈折率分布型レンズを嵌合保持したレンズホルダ26
が固定されている。In the first embodiment, a lens holder 26 has a gradient index lens fitted and held as a lens body 25 in a holding cylinder 10.
is fixed.
レンズ体の他方の鏡面に対向して入射光導入端部27及
び出射光導出端部28が設けられる。これらの入射光導
入端部及び出射光導出端部には、それぞれ入射光源及び
受光素子が接続される。第1の実施例では、入射光導入
端部27には光ファイバ31を介して入射光源16が光
学的に接続され、出射光導出端部28には光ファイバ3
2を介して受光素子17が光学的に接続される。An incident light introduction end 27 and an output light guide end 28 are provided opposite the other mirror surface of the lens body. An incident light source and a light receiving element are connected to the incident light introduction end and the output light guide end, respectively. In the first embodiment, the incident light source 16 is optically connected to the incident light introduction end 27 via the optical fiber 31, and the output light guide end 28 is connected to the optical fiber 3.
A light receiving element 17 is optically connected via 2.
入射光tJ、16からの入射光は、光ファイバ31を介
して入射光導入端部27からレンズ体25に入射され、
被検出液面11と対向するレンズ体25の鏡面から放出
されて、被検出液面11の基準位ifo上に焦点を結ぶ
ようにレンズ体25の光学特性が選定されている。The incident light from the incident light tJ, 16 enters the lens body 25 from the incident light introducing end 27 via the optical fiber 31,
The optical characteristics of the lens body 25 are selected so that the light is emitted from the mirror surface of the lens body 25 facing the liquid surface 11 to be detected and is focused on the reference position ifo of the liquid surface 11 to be detected.
この基準位置20面に被検出液面11が一致していると
、入射光は被検出液面11で反射し、被検出液面11と
対向するレンズ体25の鏡面からレンズ体25内に入射
する。この入射光は、レンズ体25の出射光導出端部2
8に達し、出射光導出端部28に対向して配設される光
ファイバ32の端面から光フアイバ32内を伝送されて
受光素子17にほぼ反射全光量が受光される。When the detected liquid level 11 coincides with this reference position 20 surface, the incident light is reflected by the detected liquid level 11 and enters the lens body 25 from the mirror surface of the lens body 25 facing the detected liquid level 11. do. This incident light is transmitted to the output light guide end 2 of the lens body 25.
8, the light is transmitted through the optical fiber 32 from the end face of the optical fiber 32 disposed opposite to the output light guide end 28, and almost the entire amount of reflected light is received by the light receiving element 17.
被検出液面11が基準位置lO以下であると、第4図に
示すように、発光素子16から供給され、光ファイバ3
1を介して伝送される入射光は、図に矢印で示すような
光路を取って被検出液面11で反射して被検出液面11
に対向する鏡面からレンズ体25内に入射され、レンズ
体25内で点線で示すように屈折するために出射光導出
端部28には到達しない。When the liquid level 11 to be detected is below the reference position lO, as shown in FIG.
The incident light transmitted through 1 takes an optical path as shown by the arrow in the figure, is reflected at the liquid surface 11 to be detected, and reaches the liquid surface 11 to be detected.
The light enters the lens body 25 from the mirror surface facing the , and is refracted within the lens body 25 as shown by the dotted line, so that it does not reach the output light guide end 28 .
このため、受光素子17には被検出液面11からの反射
光は入射しないので、被検出液面11が基準位置β0か
らずれたことが検出される。Therefore, the reflected light from the liquid surface 11 to be detected does not enter the light receiving element 17, so that it is detected that the liquid surface 11 to be detected has deviated from the reference position β0.
被検出液面11が基4I!位置1oを越えて上界してい
ると、第5図に示すように、被検出液面11で反射した
反射光は点線で示すような光路を経て、レンズ体25の
入射光導入端部27及び出射光導出端部28が設けられ
ている鏡面に達するが出射光導出端部28とはずれた位
置に到達する。The detected liquid level 11 is base 4I! As shown in FIG. 5, the reflected light reflected from the liquid surface 11 to be detected passes through the optical path shown by the dotted line and reaches the incident light introducing end 27 of the lens body 25. Then, it reaches the mirror surface where the emitted light guiding end 28 is provided, but it reaches a position away from the emitted light guiding end 28.
従って、この場合にも被検出液面11での反射光は、受
光素T−17では受光されず、被検出液面11が基準位
置β0からずれたことが検出される。Therefore, in this case as well, the light reflected by the liquid surface 11 to be detected is not received by the light receiving element T-17, and it is detected that the liquid surface 11 to be detected has deviated from the reference position β0.
被検出液面が所定値以上になると、保持筒内において、
レンズ体の一方の鏡面と被検出液面間に密封空間が形成
されるように構成される。When the liquid level to be detected exceeds a predetermined value, inside the holding cylinder,
A sealed space is formed between one mirror surface of the lens body and the liquid surface to be detected.
即ち、第1の実施例において、保持筒体10の周面は気
密構造に形成され、レンズ体25はレンズホルダ26に
対向部分において間隙がなく気密状態で取り付けられ、
レンズホルダ26も、保持筒体10に対して相互に間隙
がなく気密状態で保持固定されている。That is, in the first embodiment, the circumferential surface of the holding cylinder 10 is formed in an airtight structure, and the lens body 25 is attached to the lens holder 26 in an airtight state with no gap at the opposing portion.
The lens holder 26 is also held and fixed to the holding cylinder 10 in an airtight manner with no gaps between them.
従って、基準位置β0を越えて被検出液面11が上界す
ると、レンズ体25の被検出液面11と対向する鏡面と
被検出液面11及び保持筒体1゜に囲まれる密封空間の
気圧が増加する。このため被検出液面11が上昇を続け
てもその上昇は所定位置を越えることがなく被検出液が
レンズ体25に触れることはない。Therefore, when the detected liquid level 11 rises above the reference position β0, the air pressure in the sealed space surrounded by the mirror surface of the lens body 25 facing the detected liquid level 11, the detected liquid level 11, and the holding cylinder 1° increases. increases. Therefore, even if the liquid level 11 to be detected continues to rise, the rise will not exceed a predetermined position, and the liquid to be detected will not come into contact with the lens body 25.
第6図に同一部分に同一符号を付してその構成を示すの
は、この発明の第2の実施例であり、この実施例では保
持筒体10の端部が被検出液内に挿入した状態で配設さ
れ、被検出液内に位置する保持筒体10の周面に対して
連通孔40が形成される。この連通孔40は、被検出液
面11がy&学位置10にある時には被検出液内に位=
するように形成される。The second embodiment of the present invention is shown in FIG. 6 by assigning the same reference numerals to the same parts, and in this embodiment, the end of the holding cylinder 10 is inserted into the liquid to be detected. A communication hole 40 is formed in the circumferential surface of the holding cylinder 10 located in the liquid to be detected. This communication hole 40 is located within the liquid to be detected when the liquid level 11 to be detected is at the y & position 10.
It is formed to
第6図に示す第2の実施例では、レンズ体25としては
凸レンズが用いられ、レンズホルダ26に凸レンズが収
容され、凸レンズを収容したレンズホルダ26が保持筒
体10に対して気密的に固定される。凸レンズは一方の
鏡面を被検出液面11に対向させてレンズホルダ26に
収容され、この実施例では凸レンズの他方の鏡面に対向
して、入射光導入端部及び出射光導出端部を含む共通端
部42が設けられる。この共通端部42に光ファイバ4
3の一端側が光学的に接続され、光ファイバ43の他端
には方向性結合器45が接続される。In the second embodiment shown in FIG. 6, a convex lens is used as the lens body 25, the convex lens is housed in a lens holder 26, and the lens holder 26 housing the convex lens is airtightly fixed to the holding cylinder 10. be done. The convex lens is housed in the lens holder 26 with one mirror surface facing the liquid surface 11 to be detected, and in this embodiment, a common lens including an incident light introduction end and an output light guide end is placed opposite the other mirror surface of the convex lens. An end 42 is provided. The optical fiber 4 is connected to this common end 42.
One end of the optical fiber 43 is optically connected, and the other end of the optical fiber 43 is connected to a directional coupler 45.
この方向性結合器45には入射光ファイバ46及び出射
光ファイバ47が接続され、これらの入射光ファイバ4
6及び出射光ファイバ47に対してそれぞれ発光素子1
6及び受光素子17が光学的に接続される。An input optical fiber 46 and an output optical fiber 47 are connected to this directional coupler 45.
6 and output optical fiber 47, respectively.
6 and the light receiving element 17 are optically connected.
この場合基準位置にある被検出液面11からの反射光は
レンズ体25で集束されるが、その集束光径は共通端部
42において光ファイバ43の受光面の直径にほぼ同一
になるように構成されている。従って共通端部42にお
いて集束光はレンズ体25に対向するように配設されて
いる光ファイバ43にほぼ全光量が入射することになる
。卯ち発光素子16から発せられる入射光が入射光ファ
イバ46、方向性結合器45、光ファイバ43を介して
伝送されて、レンズ体25により基準位置10上に焦点
を結ぶ。In this case, the reflected light from the detected liquid surface 11 at the reference position is focused by the lens body 25, and the diameter of the focused light is made to be approximately the same as the diameter of the light receiving surface of the optical fiber 43 at the common end 42. It is configured. Therefore, almost the entire amount of the focused light at the common end portion 42 is incident on the optical fiber 43 which is disposed so as to face the lens body 25. Incident light emitted from the light emitting element 16 is transmitted via the input optical fiber 46, the directional coupler 45, and the optical fiber 43, and is focused on the reference position 10 by the lens body 25.
基準位TLIloに被検出液面11が一致していると、
入射光は被検出液面11で反射し、レンズ体25で光フ
ァイバ43の受光面上に集束される。When the detected liquid level 11 matches the reference position TLIlo,
The incident light is reflected by the liquid surface 11 to be detected, and is focused by the lens body 25 onto the light receiving surface of the optical fiber 43.
このために、被検出液面11が基準位置ioに一致した
状態では、被検出液面11からの反射光量がほぼ全量光
ファイバ43に入射する。光ファイバ43への入射光は
光フアイバ43内を伝送され、方向性結合器45から出
射光ファイバ47に導かれ、受光素子17により受光さ
れる。For this reason, when the liquid surface 11 to be detected coincides with the reference position io, almost the entire amount of light reflected from the liquid surface 11 to be detected is incident on the optical fiber 43. The light incident on the optical fiber 43 is transmitted through the optical fiber 43, guided from the directional coupler 45 to the output optical fiber 47, and received by the light receiving element 17.
第6図に示す第2の実施例において、被検出液面11が
基準位置!0より低下すると、第7図に示すように光フ
ァイバ43からレンズ体25を通うて被検出液面11に
投射される光は被検出液面11で反射し、矢印で示す光
路を取ってレンズ体25に入射する。この入射光の光フ
ァイバ43の受光面位置での光径はRとなり、光ファイ
バ43の受光面の直径rよりも、かなり大きい値となる
。In the second embodiment shown in FIG. 6, the detected liquid level 11 is at the reference position! When the light falls below 0, as shown in FIG. 7, the light that passes from the optical fiber 43 through the lens body 25 and is projected onto the liquid surface to be detected 11 is reflected by the liquid surface to be detected 11, takes the optical path shown by the arrow, and passes through the lens. The light enters the body 25. The optical diameter of this incident light at the light receiving surface position of the optical fiber 43 is R, which is considerably larger than the diameter r of the light receiving surface of the optical fiber 43.
このために、光ファイバ43への入射光量は伝to(−
) に低下し、光ファイバ43を介して1G(−)
に低下する。For this reason, the amount of light incident on the optical fiber 43 is transmitted to (-
) and 1G(-) via the optical fiber 43.
decreases to
第6図に示す第2の実施例において、被検出液面11が
基準位置10より上昇すると、光ファイバ43からの入
射光はレンズ25で集束されて第8図に矢印で示す光路
をとって被検出液面11に投射され、被検出液面11で
反射して矢印で示すような光路で共通端部42に達する
。In the second embodiment shown in FIG. 6, when the liquid level 11 to be detected rises above the reference position 10, the incident light from the optical fiber 43 is focused by the lens 25 and takes the optical path shown by the arrow in FIG. The light is projected onto the liquid surface 11 to be detected, is reflected by the liquid surface 11, and reaches the common end portion 42 along an optical path as shown by the arrow.
この場合共通端部42における光束径はR1となり、こ
の場合も光束径は光ファイバ43の受光面の直径rより
も大きい値となる。この場合には光ファイバ43を介し
て受光素子17で受光される光量は伝送系内での減衰を
無視すると、光ファR1
下し、光ファイバ43を介して 受光素子17でI
第7図及び第812]の示す場合には、基準位置
11Oよりの被検出液面11のずれと、共通端部42
における反射光の光束径RもしくはR,とを定量的に対
応付けることが可能である。従って第6図に示すこの発
明の第2の実施例においては、被検出液面11の基準位
置1oからのずれを、定量的に検出することが出来る。In this case, the diameter of the light beam at the common end portion 42 is R1, which is also larger than the diameter r of the light receiving surface of the optical fiber 43. In this case, if the amount of light received by the light receiving element 17 via the optical fiber 43 is ignored, the amount of light received by the light receiving element 17 is determined by the amount of light received by the light receiving element 17 via the optical fiber 43, if the attenuation within the transmission system is ignored. No. 812], the reference position
The deviation of the detected liquid level 11 from 11O and the common end 42
It is possible to quantitatively associate the luminous flux diameter R or R of the reflected light in . Therefore, in the second embodiment of the present invention shown in FIG. 6, the deviation of the liquid level 11 to be detected from the reference position 1o can be quantitatively detected.
この第2の実施例においても、被検出液面11上におい
て、保持筒体10に囲まれて密封空間が形成されるので
、被検出液面11は保持筒体10内では所定値を越えて
上昇することがない。このためにこの第2の実施例にお
いても液面検出器の凸レンズ25その他の光学部品が被
検出液に触れることがない。従って、被検出液が腐蝕性
の液体であっても測定が可能であり、また光学部品に対
する汚れ取りや定期的な洗滌作業が不用である。In this second embodiment as well, a sealed space surrounded by the holding cylinder 10 is formed above the liquid level 11 to be detected, so that the liquid level 11 to be detected exceeds a predetermined value within the holding cylinder 10. It never rises. Therefore, in this second embodiment as well, the convex lens 25 and other optical parts of the liquid level detector do not come into contact with the liquid to be detected. Therefore, even if the liquid to be detected is a corrosive liquid, measurement is possible, and there is no need to remove dirt or periodically wash the optical parts.
第6図に示す第2の実施例において、保持筒体10に形
成した連通孔40は、第1図に示す第1の実施例に対し
ても形成することが出来る。連通TL40を保持筒体1
0に形成することにより、保持筒体10内外にわたる被
検出液の連結を粗にして連通孔40にダンパ作用を持た
せ、例えば保持筒体10外の被検出液の波立ちの影響を
保持筒体10内で遮断することが出来る。The communication hole 40 formed in the holding cylinder 10 in the second embodiment shown in FIG. 6 can also be formed in the first embodiment shown in FIG. Cylindrical body 1 holding communication TL40
0, the connection of the liquid to be detected between the inside and outside of the holding cylinder 10 is made rough, and the communicating hole 40 has a damper effect, so that, for example, the influence of the ripples of the liquid to be detected outside the holding cylinder 10 is reduced. It can be shut off within 10 seconds.
この連通孔40を変形して、第9図に示すように、切り
割り50を保持筒体10に形成することも可能である。It is also possible to modify this communication hole 40 to form a cut 50 in the holding cylinder 10, as shown in FIG.
また、第10図に第6図の第2の実施例に適用した場合
を示すように、保持筒体10の被検出液に接する開放面
の開放面積を狭めた構成のものも実現可能である。Furthermore, as shown in FIG. 10 when applied to the second embodiment of FIG. 6, it is also possible to realize a configuration in which the open area of the open surface of the holding cylinder 10 that comes into contact with the liquid to be detected is narrowed. .
I!llち、第10図に示すように、保持筒体10の外
径を光ファイバ43が連結される端面と反対側において
狭め、外径が狭められた突出円筒部51を形成し、この
突出円筒部51の突出端面を開放面とする。このように
すれば保持筒体lOの内部は突出円筒部51において被
検出液と粗に連結し、突出円筒部51がダンパ作用をし
て、例えば保持筒体10外での被検出液の波立ちの影響
を保持筒体10内で除去することが出来る。この場合第
10図では図示していないが突出円筒部51と連結孔或
は切り割りとを併用することも可能である。I! ll, as shown in FIG. 10, the outer diameter of the holding cylinder 10 is narrowed on the side opposite to the end surface to which the optical fiber 43 is connected to form a protruding cylindrical portion 51 with a narrowed outer diameter, and this protruding cylinder The protruding end surface of the portion 51 is an open surface. In this way, the inside of the holding cylinder lO is roughly connected to the liquid to be detected at the protruding cylinder part 51, and the protruding cylinder part 51 acts as a damper, causing the liquid to be detected to ripple outside the holding cylinder 10. The influence of can be removed within the holding cylinder 10. In this case, although not shown in FIG. 10, it is also possible to use the protruding cylindrical portion 51 and a connecting hole or a cutout.
このようにしてこの発明によるといずれの実施例におい
ても、被検出液面が基準位置にあるか否かの測定が精度
よく、且つ、光学部品を被検出液に接触させずに行なう
ことが可能である。従って、液面検出器の光学部品に対
する汚れ取りや定期的な洗滌作業が不用であり、また腐
蝕性の被検出液に対しても液面検出を行なうことも出来
る。In this way, according to the present invention, in any of the embodiments, it is possible to accurately measure whether or not the liquid level to be detected is at the reference position, and to do so without bringing the optical component into contact with the liquid to be detected. It is. Therefore, it is not necessary to remove dirt from the optical components of the liquid level detector or to periodically wash them, and the liquid level can also be detected even for corrosive liquids to be detected.
さらにレンズ体として所定のレンズを使用することによ
り被検出液面の基準位置からのずれを定量的に測定する
ことも出来る。従って被検出液圧による密封空間の体積
変化を検知して被検出液面位置を連続的に計測すること
も出来る。Furthermore, by using a predetermined lens as the lens body, it is also possible to quantitatively measure the deviation of the liquid level to be detected from the reference position. Therefore, the position of the liquid level to be detected can be continuously measured by detecting the change in the volume of the sealed space due to the liquid pressure to be detected.
「発明の効果」
以上詳細に説明したように、この発明によると光学部品
に対する汚れ取りや定期的な洗滌作業が不用であり、腐
蝕性の被検出液に対する高精度の液面検出が可能な液面
検出器を提供することが可能となる。"Effects of the Invention" As explained in detail above, according to the present invention, there is no need to remove dirt from optical parts or to periodically wash them, and the liquid level of corrosive liquids to be detected can be detected with high precision. It becomes possible to provide a surface detector.
第1図は、この発明の第1の実施例の構成を示す断面図
、第2図及び第3図はそれぞれ従来提案されている液面
検出器の構成を示す原理図、第4図は、第1図に示す第
1の実施例で被検出液面が基準位置より低下した場合の
動作原理を示す図、第5図は、第1図に示す第1の実施
例で被検出液面が基準位置より上昇した場合の動作原理
を示す図、第6図は、この発明の第2の実施例の構成を
示す断面図、第7図は、第6図に示す第2の実施例で被
検出液面が基準位置より低下した場合の動作原理を示す
図、第8図は、第6図に示す第2の実施例で被検出液面
が基準位置より上昇した場合の動作原理を示す図、第9
図は、第6図に示す第2の実施例において保持筒体に切
り割りを形成した場合の構成を示す図、第10図は、第
6図に示す第2の実施例において保持筒体に突出円筒部
を形成した場合の構成を示す図である。
10:保持筒体、11:被検出液面、12ニブリズム、
16:発光素子、17:受光素子、20゜21:光ファ
イバ、22:タンク、25:レンズ体、26:レンズホ
ルダ、27:入射光導入端部、28:出射光導出端部、
31.32+光フアイバ、40:連通孔、42:共通端
部、43:光ファイバ、45二方向性結合器、46:入
射光ファイバ、47:出射光ファイバ、50:切り割り
、51:突出円筒部。FIG. 1 is a sectional view showing the configuration of a first embodiment of the present invention, FIGS. 2 and 3 are principle diagrams showing the configuration of a conventionally proposed liquid level detector, and FIG. Fig. 5 shows the operating principle when the liquid level to be detected falls below the reference position in the first embodiment shown in Fig. 1; FIG. 6 is a sectional view showing the structure of the second embodiment of the present invention, and FIG. 7 is a diagram showing the principle of operation when raised from the reference position. FIG. 8 is a diagram showing the principle of operation when the detected liquid level falls below the reference position. FIG. 8 is a diagram showing the principle of operation when the detected liquid level rises above the reference position in the second embodiment shown in FIG. , No. 9
The figure shows the configuration when a cut is formed in the holding tube in the second embodiment shown in FIG. 6, and FIG. It is a figure which shows the structure when a cylindrical part is formed. 10: Holding cylinder, 11: Detected liquid level, 12 Nibrism,
16: Light emitting element, 17: Light receiving element, 20° 21: Optical fiber, 22: Tank, 25: Lens body, 26: Lens holder, 27: Incident light introducing end, 28: Outgoing light guiding end,
31.32 + optical fiber, 40: communication hole, 42: common end, 43: optical fiber, 45 bidirectional coupler, 46: input optical fiber, 47: output optical fiber, 50: slit, 51: protruding cylindrical part .
Claims (1)
配され、この保持筒体内に一方の鏡面を前記被検出液面
に対向させてレンズ体が取り付けられ、このレンズ体の
他方の鏡面に対向して入射光導入端部及び出射光導出端
部が設けられ、これら入射光導入端部及び出射光導出端
部にはそれぞれ入射光源及び受光素子が接続され、前記
入射光導入端部からの入射光は基準位置にある前記被検
出液面上に焦点を結び、この被検出液面で反射して前記
受光素子でその反射光のほぼ全光量が検出され、前記被
検出液面が所定値以上となると前記保持筒内において前
記レンズ体の一方の鏡面と前記被検出液面間に密封空間
が形成されるように構成されてなることを特徴とする液
面検出器。A holding cylinder is disposed with at least a portion thereof positioned above the liquid surface to be detected, a lens body is attached within the holding cylinder with one mirror surface facing the liquid surface to be detected, and the other side of the lens body is mounted with one mirror surface facing the liquid surface to be detected. An incident light introduction end and an output light guide end are provided opposite to the mirror surface, and an incident light source and a light receiving element are connected to the incident light introduction end and the output light guide end, respectively, and the incident light introduction end The incident light is focused on the liquid surface to be detected at the reference position, is reflected by the liquid surface to be detected, and almost the entire amount of the reflected light is detected by the light receiving element, and the liquid surface to be detected is detected by the light receiving element. A liquid level detector characterized in that, when a predetermined value or more is exceeded, a sealed space is formed in the holding cylinder between one mirror surface of the lens body and the liquid level to be detected.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6552886A JPS62222124A (en) | 1986-03-24 | 1986-03-24 | Liquid level detector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6552886A JPS62222124A (en) | 1986-03-24 | 1986-03-24 | Liquid level detector |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS62222124A true JPS62222124A (en) | 1987-09-30 |
Family
ID=13289602
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP6552886A Pending JPS62222124A (en) | 1986-03-24 | 1986-03-24 | Liquid level detector |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS62222124A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007322529A (en) * | 2006-05-30 | 2007-12-13 | Kyocera Mita Corp | Liquid level controller for liquid developer and image forming apparatus |
CN103884402A (en) * | 2014-04-03 | 2014-06-25 | 常州麦吉尔测试系统技术有限公司 | Hard-light-interference-resisting liquid level detection device |
-
1986
- 1986-03-24 JP JP6552886A patent/JPS62222124A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007322529A (en) * | 2006-05-30 | 2007-12-13 | Kyocera Mita Corp | Liquid level controller for liquid developer and image forming apparatus |
CN103884402A (en) * | 2014-04-03 | 2014-06-25 | 常州麦吉尔测试系统技术有限公司 | Hard-light-interference-resisting liquid level detection device |
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