JPH0336183B2 - - Google Patents
Info
- Publication number
- JPH0336183B2 JPH0336183B2 JP58094411A JP9441183A JPH0336183B2 JP H0336183 B2 JPH0336183 B2 JP H0336183B2 JP 58094411 A JP58094411 A JP 58094411A JP 9441183 A JP9441183 A JP 9441183A JP H0336183 B2 JPH0336183 B2 JP H0336183B2
- Authority
- JP
- Japan
- Prior art keywords
- high viscosity
- viscosity fluid
- sensor
- leakage sensor
- resin layer
- 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.)
- Expired - Lifetime
Links
- 239000012530 fluid Substances 0.000 claims description 42
- 239000011347 resin Substances 0.000 claims description 20
- 229920005989 resin Polymers 0.000 claims description 20
- 239000007788 liquid Substances 0.000 claims description 16
- 238000010438 heat treatment Methods 0.000 claims description 14
- 238000005259 measurement Methods 0.000 claims description 9
- 238000001514 detection method Methods 0.000 description 19
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000004904 shortening Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 2
- 230000007257 malfunction Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000000087 stabilizing effect Effects 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
- Examining Or Testing Airtightness (AREA)
Description
【発明の詳細な説明】
［産業上の利用分野］
この発明は漏液センサに関し、特に高粘度流体
などについて、検知時間の短縮や検知の安定化な
どの特性向上するための漏液センサに関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a liquid leakage sensor, and particularly to a liquid leakage sensor for improving characteristics such as shortening detection time and stabilizing detection for high viscosity fluids.
［従来の技術］
従来、例えば油類の漏出検知のためのセンサと
しては、導電性樹脂シートに接する離間配置した
一対の電極間の抵抗値の変化によつて検知するも
の、或いは通液可能にした同軸状ケーブルを用
い、このケーブル中への油類の浸入をパルス法等
によつて検知するものなどがある。[Prior Art] Conventionally, sensors for detecting the leakage of oil, for example, have detected by detecting a change in resistance value between a pair of spaced apart electrodes in contact with a conductive resin sheet, or sensors that allow liquid to pass through the sensor. There are some methods that use a coaxial cable that has been heated and detect the infiltration of oil into the cable using a pulse method or the like.
［発明が解決しようとする課題］
しかしながら、これらの漏液センサについて
は、例えば室温、または、低温雰囲気において高
粘度の流体を検知する場合、その被検知流体がこ
れらの漏液センサに容易に浸入することができな
いか、または浸入に長時間を要するため使用が不
可能な場合がある。また、これらの漏液センサで
は、水蒸気その他の気体を吸収することによる抵
抗変化が誤動作になる場合もある。[Problems to be Solved by the Invention] However, when detecting a highly viscous fluid at room temperature or in a low-temperature atmosphere, for example, when detecting a highly viscous fluid at room temperature or in a low-temperature atmosphere, the fluid to be detected easily enters the sensor. In some cases, it may not be possible to do so, or it may take a long time to infiltrate, making it impossible to use. Furthermore, in these liquid leakage sensors, resistance changes due to absorption of water vapor or other gases may cause malfunctions.
そこでこの発明はこれらの欠点を除去し、上記
のような高粘度流体などについて、漏洩センサの
検知時間の短縮や検知の安定化等の特性向上を目
的とする。 Therefore, the present invention aims to eliminate these drawbacks and improve the characteristics of the leak sensor, such as shortening the detection time and stabilizing the detection, with respect to the above-mentioned high viscosity fluids.
［課題を解決するための手段］
本発明は上記課題を達成するためになされたも
ので、導電性樹脂層と、該導電性樹脂層に導電接
続した一対ないし二対の電極と、これらの外周に
設けた外被とを備えてなる漏液センサにおいて、
被検知用高粘度流体の粘度を低下させるために、
該導電性樹脂層に前記の電極を介して加熱電流を
供給することによつて加温することを特徴とする
高粘度流体用漏液センサを構成する。[Means for Solving the Problems] The present invention has been made to achieve the above-mentioned problems, and includes a conductive resin layer, one or two pairs of electrodes conductively connected to the conductive resin layer, and their outer peripheries. In a liquid leakage sensor comprising an outer cover provided on the
In order to reduce the viscosity of the high viscosity fluid to be detected,
A leakage sensor for high viscosity fluid is constructed, characterized in that the conductive resin layer is heated by supplying a heating current to the conductive resin layer through the electrode.
また、上記の高粘度流体用漏液センサにおい
て、前記の電極は一対の計測用端子と、この一対
の計測用端子を挟む一対の通電加温用端子との四
端子構成であることを特徴とする高粘度流体用漏
液センサを構成するものも含まれる。 Further, in the above liquid leakage sensor for high viscosity fluid, the electrode has a four-terminal configuration including a pair of measurement terminals and a pair of energization heating terminals sandwiching the pair of measurement terminals. It also includes those constituting a leakage sensor for high viscosity fluid.
［作用］
この発明によれば、導電性樹脂層と、該導電性
樹脂層に導電接続した一対ないし二対の電極と、
これらの外周に設けた外被とを備えてなる漏液セ
ンサにおいて、被検知用高粘度流体の粘度を低下
させるために、該導電性樹脂層に前記の電極を介
して加熱電流を供給することによつて加温するこ
とを特徴とする高粘度流体用漏液センサを構成す
る。[Function] According to the present invention, a conductive resin layer, one or two pairs of electrodes conductively connected to the conductive resin layer,
In a liquid leakage sensor equipped with a jacket provided on the outer periphery of the liquid leakage sensor, a heating current is supplied to the conductive resin layer through the electrode in order to reduce the viscosity of the high-viscosity fluid to be detected. A liquid leakage sensor for high viscosity fluid is constructed, which is characterized in that it is heated by heating.
また、上記の高粘度流体用漏液センサにおい
て、前記の電極は一対の計測用端子と、この一対
の計測用端子を挟む一対の通電加温用端子との四
端子構成であることを特徴とする高粘度流体用漏
液センサを構成するものも含まれる。 Further, in the above liquid leakage sensor for high viscosity fluid, the electrode has a four-terminal configuration including a pair of measurement terminals and a pair of energization heating terminals sandwiching the pair of measurement terminals. It also includes those constituting a leakage sensor for high viscosity fluid.
この構成によれば、例えば室温または室温以下
の低温雰囲気において高粘度の流体を検知する場
合でも、その被検知流体は、この高粘度流体用漏
液センサ本体によつて一定温度に加温され、高粘
度流体がその加温により粘度が低下し、この漏液
センサへの浸入が容易になる。 According to this configuration, even when detecting a highly viscous fluid at room temperature or a low-temperature atmosphere below room temperature, the fluid to be detected is heated to a constant temperature by the high viscosity fluid leakage sensor main body, The viscosity of the high viscosity fluid decreases due to heating, making it easier to enter the leakage sensor.
従つて、これにより検知までの時間を短縮する
ことができ、しかも雰囲気ガスや湿気などによる
抵抗値の変化が無くなり誤検知を防止できる。 Therefore, the time until detection can be shortened, and there is no change in resistance value due to atmospheric gas, moisture, etc., and false detection can be prevented.
なお、この高粘度流体用漏液センサの加温は、
漏液検知を目的とする導電性樹脂層がある設定温
度まで上昇するのに必要な電流を流すことによつ
て行う。 The heating of this leakage sensor for high viscosity fluids is as follows:
This is done by passing the current necessary to raise the temperature of the conductive resin layer whose purpose is to detect liquid leakage to a certain set temperature.
［実施例］
次に、図によつてこの発明を更に詳細に説明す
る。[Example] Next, the present invention will be explained in more detail with reference to the drawings.
第１図はこの発明による漏洩センサの一実施例
を示す横断面図である。図において高粘度流体用
漏洩センサ１は、導電性樹脂層２に一対の電極
３、電極３′が電気的に接続して設けられ、それ
らの外周に外被４を設けて形成されている。この
場合、導電性樹脂層２は、従来のセンサに比較し
て低抵抗の1KΩに設定されている。この高粘度
流体用漏洩センサ１に電源５、電圧計６及び電流
計７を図示のように接続して抵抗の経時変化を見
たところ第２図のような特性が、また漏液検知速
度を測定したところ第３図のような特性が得られ
た。 FIG. 1 is a cross-sectional view showing an embodiment of a leakage sensor according to the present invention. In the figure, a leak sensor 1 for high viscosity fluid is formed by providing a conductive resin layer 2 with a pair of electrodes 3 and 3' electrically connected to each other, and a jacket 4 provided around their outer peripheries. In this case, the conductive resin layer 2 is set to have a resistance of 1KΩ, which is lower than that of conventional sensors. When a power source 5, a voltmeter 6, and an ammeter 7 were connected to this leak sensor 1 for high viscosity fluid as shown in the figure, and the change in resistance over time was observed, the characteristics shown in Figure 2 were also found to increase the leakage detection speed. As a result of measurement, characteristics as shown in FIG. 3 were obtained.
第２図において、特性線Ａは従来の高抵抗の樹
脂層２をもつた漏洩センサの抵抗時間特性を示
し、特性線Ｂはこの発明による低抵抗の樹脂層２
をもつた高粘度流体用漏洩センサ１の抵抗時間特
性を示している。これらの特性線からわかるよう
に内部抵抗を小さくして消費電力を高めて加温手
段としたこの実施例による高粘度流体用漏洩セン
サ１によれば、時間経過によつてセンサ抵抗値が
変化せず安定しており、従来の漏洩センサのよう
に抵抗値の経時変化が無いことを示している。 In FIG. 2, a characteristic line A shows the resistance time characteristic of a conventional leak sensor having a high resistance resin layer 2, and a characteristic line B shows a resistance time characteristic of a leak sensor having a conventional high resistance resin layer 2.
2 shows the resistance time characteristics of the high viscosity fluid leakage sensor 1 having the following characteristics. As can be seen from these characteristic lines, according to the leak sensor 1 for high viscosity fluid according to this embodiment, in which the internal resistance is reduced and the power consumption is increased to increase the heating means, the sensor resistance value does not change over time. The results show that the resistance value does not change over time unlike conventional leakage sensors.
第３図は内部抵抗1KΩのこの発明による高粘
度流体用漏洩センサ１の電極３、電極３′間に直
流15ｍＡを流した場合の検知時間特性を示してい
る。図において、特性線Ｃはこの発明による高粘
度流体用漏洩センサ１の抵抗変化を、特性線Ｄは
従来の漏洩センサによる抵抗変化を示す。これら
の特性線Ｃ，Ｄと検知指示値Ｅとの交点が各セン
サの検知するまでの時間である。 FIG. 3 shows the detection time characteristics when a direct current of 15 mA is applied between the electrodes 3 and 3' of the leakage sensor 1 for high viscosity fluid according to the present invention having an internal resistance of 1 KΩ. In the figure, the characteristic line C shows the resistance change of the high viscosity fluid leak sensor 1 according to the present invention, and the characteristic line D shows the resistance change of the conventional leak sensor. The intersection of these characteristic lines C and D and the detection instruction value E is the time required for detection by each sensor.
以上の関係からこの発明による高粘度流体用漏
洩センサ１の検知時間は30分であるに対し、直流
１ｍＡを流した従来の漏洩センサの検知までの時
間は112分であり、検知までの時間を約1/4に短縮
できたことがわかる。 From the above relationship, the detection time of the leak sensor 1 for high viscosity fluid according to the present invention is 30 minutes, whereas the detection time of the conventional leak sensor with a DC current of 1 mA is 112 minutes; It can be seen that the time was reduced to about 1/4.
第４図はこの発明による他の実施例を示し、こ
の場合従来と同様な漏洩センサ８を用いるが、電
源９の電圧を高めて大きな電流を漏洩センサ８に
流すことによつて高粘度流体用漏洩センサ８が加
温されるようにしたものである。 FIG. 4 shows another embodiment according to the present invention, in which a leak sensor 8 similar to the conventional one is used, but by increasing the voltage of the power supply 9 and passing a large current through the leak sensor 8, it is possible to use a high-viscosity fluid. The leak sensor 8 is heated.
この場合のセンサの抵抗値経時変化は、第５図
の特性線Ｇに示すようにほとんどなく、従来の漏
洩センサの特性線Ｈと比較すると安定した抵抗値
となつている。また、漏液検知時間は第６図の特
性線Ｉと検知指示値Ｊとの交点で示されるように
4.5分であり、従来の特性線Ｋと検知指示値Ｊと
の交点に示す検知時間27分に比較して1/6に短縮
されたことがわかる。 In this case, there is almost no change in the resistance value of the sensor over time, as shown by the characteristic line G in FIG. 5, and the resistance value is stable when compared with the characteristic line H of the conventional leakage sensor. In addition, the leakage detection time is shown by the intersection of the characteristic line I and the detection indication value J in Figure 6.
It can be seen that the detection time is 4.5 minutes, which is 1/6 of the conventional detection time of 27 minutes, which is shown at the intersection of the characteristic line K and the detection instruction value J.
第７図はこの発明による別の実施例を示す。こ
の場合、高粘度流体用漏洩センサ１０は四端子構
成で、そのうちの二端子１１を検知用とし漏洩に
よる抵抗増加を計測する。他の二端子１５を通電
加温用として用いている。図において、計測用端
子１１には交流電源１２より給電して電圧計１３
及び電流計１４により計測し、通電加温用端子１
５には直流電流供給源１６が接続された例を示し
ている。この場合においても第４図の実施例と同
様な効果が得られる。 FIG. 7 shows another embodiment according to the invention. In this case, the high-viscosity fluid leak sensor 10 has a four-terminal configuration, of which two terminals 11 are used for detection to measure an increase in resistance due to leakage. The other two terminals 15 are used for energization and heating. In the figure, power is supplied to the measurement terminal 11 from an AC power supply 12, and a voltmeter 13
And measured by ammeter 14, energized heating terminal 1
5 shows an example in which a DC current supply source 16 is connected. In this case as well, effects similar to those of the embodiment shown in FIG. 4 can be obtained.
［発明の効果］
以上の通りこの発明によれば、導電性樹脂層
と、該導電性樹脂層に導電接続した一対ないし二
対の電極と、これらの外周に設けた外被とを備え
てなる漏液センサにおいて、被検知用高粘度流体
の粘度を低下させるために、該導電性樹脂層に前
記の電極を介して加熱電流を供給することによつ
て加温することを特徴とする高粘度流体用漏液セ
ンサを構成することにより、低温雰囲気において
高粘度の流体が、この漏液センサ本体に達すると
一定温度に加温されて粘度が低くなり、この漏液
センサへの浸入が容易になるので検知時間を短縮
できる効果が得られ、また、センサ抵抗値が安定
するため誤動作防止効果が得られる。[Effects of the Invention] As described above, according to the present invention, the device comprises a conductive resin layer, one or two pairs of electrodes conductively connected to the conductive resin layer, and an outer cover provided on the outer periphery of these electrodes. In a liquid leakage sensor, in order to reduce the viscosity of the high viscosity fluid to be detected, the high viscosity fluid is heated by supplying a heating current to the conductive resin layer via the electrode. By configuring a liquid leakage sensor for fluids, when a highly viscous fluid in a low-temperature atmosphere reaches the leakage sensor body, it is heated to a certain temperature and its viscosity becomes low, making it easier for the fluid to enter the leakage sensor. Therefore, the effect of shortening the detection time can be obtained, and since the sensor resistance value is stabilized, the effect of preventing malfunction can be obtained.
なお、この発明は上記実施例に限定されるもの
ではなく、この発明の思想の範囲内で種々変更実
施することができる。 It should be noted that the present invention is not limited to the above-mentioned embodiments, and various modifications can be made within the scope of the idea of the present invention.
第１図はこの発明による一実施例の高粘度流体
用漏液センサの横断面図、第２図及び第３図は第
１図の高粘度流体用漏液センサの特性図、第４図
はこの発明による他の実施例の高粘度流体用漏液
センサを示す結線図、第５図及び第６図は第４図
の実施例の高粘度流体用漏液センサにおける特性
図、第７図はこの発明による別の実施例の高粘度
流体用漏液センサを示す結線図である。
１，８，１０：高粘度流体用漏洩センサ、２：
導電性樹脂層、３，３′：電極、４：外被、５：
電源、６，１３：電圧計、７，１４：電流計、
９：電源、１１：測定用端子、１２：交流電源、
１５：通電加温用端子、１６：直流電流供給源。
FIG. 1 is a cross-sectional view of a leakage sensor for high viscosity fluid according to an embodiment of the present invention, FIGS. 2 and 3 are characteristic diagrams of the leakage sensor for high viscosity fluid shown in FIG. 1, and FIG. A wiring diagram showing a leakage sensor for high viscosity fluid according to another embodiment of the present invention, FIGS. 5 and 6 are characteristic diagrams of the leakage sensor for high viscosity fluid according to the embodiment of FIG. 4, and FIG. FIG. 3 is a wiring diagram showing another embodiment of a leakage sensor for high viscosity fluid according to the present invention. 1, 8, 10: Leak sensor for high viscosity fluid, 2:
Conductive resin layer, 3, 3': electrode, 4: outer cover, 5:
Power supply, 6, 13: Voltmeter, 7, 14: Ammeter,
9: Power supply, 11: Measurement terminal, 12: AC power supply,
15: Current heating terminal, 16: DC current supply source.
Claims (1)
した一対ないし二対の電極と、これらの外周に設
けた外被とを備えてなる漏液センサにおいて、被
検知用高粘度流体の粘度を低下させるために、該
導電性樹脂層に前記の電極を介して加熱電流を供
給することによつて加温することを特徴とする高
粘度流体用漏液センサ。 ２ 特許請求の範囲第１項に記載の高粘度流体用
漏液センサにおいて、前記の電極は一対の計測用
端子と、この一対の計測用端子を挟む一対の通電
加温用端子との四端子構成であることを特徴とす
る高粘度流体用漏液センサ。[Scope of Claims] 1. A liquid leakage sensor comprising a conductive resin layer, one or two pairs of electrodes conductively connected to the conductive resin layer, and an outer cover provided on the outer periphery of these electrodes. A leakage sensor for a high viscosity fluid, characterized in that the conductive resin layer is heated by supplying a heating current through the electrode to reduce the viscosity of the high viscosity fluid. 2. In the liquid leakage sensor for high viscosity fluid according to claim 1, the electrode has four terminals including a pair of measurement terminals and a pair of energization heating terminals sandwiching the pair of measurement terminals. A liquid leakage sensor for high viscosity fluid characterized by the following configuration.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9441183A JPS59224550A (en) | 1983-05-28 | 1983-05-28 | Liquid leak sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9441183A JPS59224550A (en) | 1983-05-28 | 1983-05-28 | Liquid leak sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59224550A JPS59224550A (en) | 1984-12-17 |
| JPH0336183B2 true JPH0336183B2 (en) | 1991-05-30 |
Family
ID=14109499
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9441183A Granted JPS59224550A (en) | 1983-05-28 | 1983-05-28 | Liquid leak sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59224550A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0438283Y2 (en) * | 1985-11-29 | 1992-09-08 | ||
| RU2708682C1 (en) * | 2019-03-11 | 2019-12-11 | Общество с ограниченной ответственностью "Спецлак" (ООО "Спецлак") | Contact sensor of specific electric conductivity of liquid |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS564850B2 (en) * | 1977-09-10 | 1981-02-02 | ||
| JPS5631534A (en) * | 1979-08-18 | 1981-03-30 | Uedasa Chuzosho:Kk | Compound brake shoe with adhesion increasing material for railway vehicle |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS564850U (en) * | 1979-06-26 | 1981-01-17 |
-
1983
- 1983-05-28 JP JP9441183A patent/JPS59224550A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS564850B2 (en) * | 1977-09-10 | 1981-02-02 | ||
| JPS5631534A (en) * | 1979-08-18 | 1981-03-30 | Uedasa Chuzosho:Kk | Compound brake shoe with adhesion increasing material for railway vehicle |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59224550A (en) | 1984-12-17 |
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