JP2597028B2 - Oil leak detection method and detector - Google Patents
Oil leak detection method and detectorInfo
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- JP2597028B2 JP2597028B2 JP2064723A JP6472390A JP2597028B2 JP 2597028 B2 JP2597028 B2 JP 2597028B2 JP 2064723 A JP2064723 A JP 2064723A JP 6472390 A JP6472390 A JP 6472390A JP 2597028 B2 JP2597028 B2 JP 2597028B2
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- oil leak
- resistors
- resistance
- oil
- resistance value
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Description
【発明の詳細な説明】 〔産業上の利用分野〕 この発明は、石油タンクからの油漏れ、又は工場排水
中に含まれる油分等を検知する油漏れ検知方法及び検知
器に関するものである。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil leak detecting method and an oil leak detecting method for detecting an oil leak from an oil tank or an oil component contained in industrial wastewater.
第６図は、例えば実開昭55−181540号に示された従来
の油検知器駆動回路である。ここで油分検知素子である
抵抗体（１）と抵抗器（R1）〜（R3）とによってブリッ
ジ回路が構成されている。常時は点a,b間に電源（Ｅ）
による電圧が発生しないようバランスされている。油分
を検知したとき抵抗体（１）の電気抵抗値が増大してブ
リッジ回路のバランスが崩れると、点a,b間に電圧が発
生し、これによってトランジスタ（Tr）をオンして警報
器（10）を作動させ、警報を発する。FIG. 6 shows a conventional oil detector drive circuit disclosed in, for example, Japanese Utility Model Laid-Open No. 55-181540. Here is a oil sensing element resistor (1) and the resistor (R 1) a bridge circuit by a ~ (R 3) is constituted. Power supply (E) between points a and b
Are balanced so that no voltage due to When the electric resistance of the resistor (1) increases when the oil content is detected and the balance of the bridge circuit is lost, a voltage is generated between the points a and b, thereby turning on the transistor (T r ) to turn on the alarm. Activate (10) and issue an alarm.
前記油分検知素子として使用されている抵抗体（１）
は親油性でかつ撥水性の高分子物質中に導電性微粒子
（炭素や金属の微粒粉末）を分散させ薄膜状にして使用
されている。この抵抗体（１）に油又は親油性蒸気が接
触すれば、これが親油性であるため高分子内部に入り込
み膨潤を起こす。その結果導電性微粒子間の接触抵抗が
変化して電気抵抗が増加する。この電気抵抗の変化を検
知して油の存在を検知する。しかし経年変化による抵抗
値の増加が生じた場合又素子の切断などにより抵抗値が
無限大となったような場合、実際に油漏れがなくてもあ
たかも油漏れがあったかのように警報器（10）が警報を
発し、いわゆる誤警報になってしまう恐れがある。A resistor (1) used as the oil detecting element
Is used in the form of a thin film obtained by dispersing conductive fine particles (fine powder of carbon or metal) in a lipophilic and water-repellent polymer substance. If oil or lipophilic vapor comes into contact with the resistor (1), it enters the polymer and swells because it is lipophilic. As a result, the contact resistance between the conductive fine particles changes and the electric resistance increases. By detecting the change in the electric resistance, the presence of oil is detected. However, if the resistance value increases due to aging, or if the resistance value becomes infinite due to the cutting of the element, etc., the alarm (10 ) May cause an alarm, resulting in a so-called false alarm.
又上記以外に素子のリード線および各単位検知部を結
ぶ配線の断線が起こった場合などにも同様の誤警報が起
こる恐れがある。In addition to the above, similar erroneous alarms may occur when the lead wires of the elements and the wires connecting the respective unit detection units are broken.
この発明は、上記のような誤警報を発しない信頼性の
高い油漏れ検知方法及び検知器を提供することを目的と
する。SUMMARY OF THE INVENTION It is an object of the present invention to provide a highly reliable oil leak detection method and a detector that do not generate a false alarm as described above.
この発明にかかる請求項（１）の油漏れ検知方法は、
油漏れ検知時、その抵抗値ＲがkRに変化する実質的に同
じ抵抗値の抵抗体をｍ（２≦ｍ＜ｋ）個実質的に並列に
接続し、その並列に接続した抵抗体の合成抵抗値が（1/
m）・kR以上kR以下に変化した時、油漏れ警報を発生す
ることを特徴とする。An oil leak detection method according to claim 1 of the present invention is characterized in that:
Upon detection of an oil leak, m (2 ≦ m <k) resistors having substantially the same resistance value whose resistance value R changes to kR are connected substantially in parallel, and the resistors connected in parallel are combined. If the resistance value is (1 /
m) ・ It is characterized by generating an oil leak alarm when it changes from kR to kR.
この発明にかかる請求項（２）の油漏れ検知方法は、
油漏れ検知時、その抵抗値ＲがkRに変化する実質的に同
じ抵抗値の抵抗体をｍ（２≦ｍ＜ｋ）個実質的に並列に
接続してなる単位検知部をＮ（＜（ｋ−１）／（ｍ−
１））個直列に接続し、そのＮ個の抵抗体の合成抵抗値
が（1/m）・（kR＋Ｒ（Ｎ−１））以上kRN以下に変化し
た時に油漏れ警報を発生することを特徴とする。An oil leak detection method according to claim (2) according to the present invention,
When an oil leak is detected, m (2 ≦ m <k) resistor detection units having substantially the same resistance value whose resistance value R changes to kR are connected in a substantially parallel manner to a unit detection unit of N (<( k-1) / (m-
1)) Connected in series, an oil leak alarm is generated when the combined resistance value of the N resistors changes from (1 / m) · (kR + R (N-1)) to kRN. And
〔作用〕 本発明の請求項（１）の油漏れ検知方法においては、
通常時の抵抗値Ｒのｋ倍に変化する抵抗体をｍ（２≦ｍ
＜ｋ）個並列に接続して、その合成抵抗値が（1/m）・k
R以上kR以下に変化した時に油漏れ警報を発生する。[Operation] In the oil leak detection method according to claim (1) of the present invention,
A resistor that changes k times the resistance value R at normal time is represented by m (2 ≦ m
<K) connected in parallel and the combined resistance value is (1 / m) · k
Generates an oil leak alarm when it changes from R to kR.
本発明の請求項（２）の油漏れ検知方法においては、
油漏れ検知時に抵抗値が通常時の抵抗値Ｒのｋ倍に変化
する抵抗体をｍ（２≦ｍ＜ｋ）個並列に接続した単位検
知部をＮ個（＜（Ｋ−１）／（ｍ−１））直列に接続し
て、その全体の合成抵抗値が（1/m）・（kR＋Ｒ（Ｎ−
１））以上kRN以下に変化した時に油漏れ警報を発生す
る。In the oil leak detection method according to claim (2) of the present invention,
N (<(K−1) / (M (2)) unit detection units in which m (2 ≦ m <k) resistors whose resistance value changes k times the normal resistance value R at the time of oil leak detection are connected in parallel m-1)) connected in series and the total combined resistance value is (1 / m) · (kR + R (N−
1)) Generates an oil leak alarm when it changes to kRN or more.
第１図はこの発明の第１の実施例を示す油漏れ検知器
駆動回路図である。FIG. 1 is an oil leak detector drive circuit diagram showing a first embodiment of the present invention.
油分検知素子としての抵抗体（１），（１）を２本並
列に接続して単位検知部（２）とし、抵抗器（R1）〜
（R3）と組み合わせてブリッジ回路を構成している。常
時は、ブリッジ回路のバランスが保たれているため、点
a,b間の電位差は０となっている。油分を検知すること
によって抵抗体（１），（１）の電気抵抗が増大した時
又は図中a,c間の電気抵抗が断線等の原因で増大した時
ブリッジ回路のバランスが崩れて、点a,b間にその増大
した電気抵抗値に応じた電位差ΔＶが発生する。この電
位差ΔＶを比較器（11）が比較し、警報下限設定値（以
後min.と略す）より大きく、警報上限設定値（以後max.
と略す）より小さい範囲にあれば、油漏れ警報（AL1）
を発生し、警報上限設定値（max.）より大きければ断線
警報（AR2）を発生する。Resistor as oil sensing element (1), a unit detection unit connected (1) to two parallel (2), the resistor (R 1) ~
(R 3 ) to form a bridge circuit. At all times, the balance of the bridge circuit is maintained,
The potential difference between a and b is zero. When the electric resistance of the resistors (1) and (1) increases due to the detection of oil, or when the electric resistance between a and c in the figure increases due to disconnection or the like, the balance of the bridge circuit is lost, and A potential difference ΔV corresponding to the increased electric resistance value is generated between a and b. The potential difference ΔV is compared by a comparator (11) and is larger than an alarm lower limit set value (hereinafter abbreviated as “min.”).
Abbreviated as below), the oil leak alarm (AL1)
Is generated, and a disconnection alarm (AR2) is generated if it is larger than the alarm upper limit set value (max.).
ここでmin.,max.をどのように設定するかを説明す
る。まず単位検知部のリード線部２ヶ所（図中Ａ又は
Ａ′で示す部分）又は配線部（図中Ｂで示す部分）等が
切断してa,c間の抵抗が無限大になった場合に対応して
生じる点a,b間の電位差の値をmax.の値とする。Here, how to set min. And max. Will be described. First, when the two lead wires of the unit detection unit (parts indicated by A or A 'in the figure) or the wiring parts (parts indicated by B in the figure) are cut, and the resistance between a and c becomes infinite. Let the value of the potential difference between points a and b corresponding to the value of .alpha. Be the value of max.
次にmin.について説明する。今例えば１つの抵抗体の
通常時の抵抗値をＲとして、油分を検知した時に抵抗値
がkRになるとすれば、この同じ抵抗体（１）を２本並列
にしてある第１図の単位検知部（２）の場合は抵抗体
（１），（１）が両方とも油分を検知した時それらの合
成抵抗値、すなわちa,c間の抵抗が（1/2）・kRになる。
したがってこのa,c間の抵抗が（1/2）・kRになった場合
に対応する点a,b間の電位差の値がmin.である。以後簡
単のためにa,b間の電位差min.を生じさせるところの対
応するa,c間の抵抗値をMIN.とする。Next, min. Will be described. Assuming that the resistance value of one resistor is R when the normal resistance value of one resistor is R, and the resistance value becomes kR when oil is detected, the unit detection of FIG. In the case of the part (2), when both the resistors (1) and (1) detect oil, their combined resistance value, that is, the resistance between a and c becomes (1/2) · kR.
Therefore, the value of the potential difference between the points a and b corresponding to the case where the resistance between the points a and c becomes (1/2) · kR is min. Hereinafter, for the sake of simplicity, the corresponding resistance value between a and c that causes a potential difference min. Between a and b is referred to as MIN.
更に、このMIN.の設定値が（1/2）・kRの時、単位検
知部（２）の抵抗体（１），（１）のうち１つの抵抗体
（１）が切断したり、リード線部が断線したりすると単
位検知部（２）の抵抗は増大してＲに変化する。この場
合に油漏れ警報が誤発生されないためには Ｒ＜MIN.（＝（1/2）・kR） …（１） の関係を満足する必要がある。従って（１）式を解くと
ｋ＜２である必要がある。Further, when the set value of the MIN. Is (1/2) · kR, one of the resistors (1) and (1) of the unit detection section (2) is disconnected or the lead is disconnected. When the line section is broken, the resistance of the unit detection section (2) increases and changes to R. In this case, it is necessary to satisfy the relationship of R <MIN. (= (1/2) · kR) (1) in order to prevent an erroneous oil leak alarm from being generated. Therefore, solving equation (1) requires that k <2.
又このような１つの抵抗体（１）が切断している時で
も正常な方の抵抗体（１）が油分を検知した時はその抵
抗体（１）抵抗値はkRとなり、これは前述のMIN.の値
（1/2）・kRより大きいため油漏れ警報を発生すること
になる。Even when one such resistor (1) is disconnected, when the normal resistor (1) detects oil, the resistance of that resistor (1) is kR, which is the same as that described above. Since it is greater than the value of MIN. (1/2) · kR, an oil leak alarm will be generated.
又、以上の第１の実施例では抵抗体（１）を２本並列
（ｍ＝２）にした単位検知部（２）を有するものについ
て説明したが、抵抗体（１）を３本並列にした単位検知
部を有する場合もほとんど同様であり、MIN.は（1/3）k
Rとなる。又その時ｋはｋ＞３の条件を、満足する必要
がある。同様にしてｍ本の抵抗体（１）を並列に接続し
た場合、MIN.は（1/m）・kRとなり、ｋはｋ＞ｍの条件
を満足することが必要となる。以上のように何本もの抵
抗体を並列にした単位検知部を使用することは可能であ
るが、実際の使用では２〜３本程度が適切であろう。In the first embodiment described above, the unit detection unit (2) in which two resistors (1) are arranged in parallel (m = 2) is described. However, three resistors (1) are arranged in parallel. It is almost the same when the unit detection unit is provided, and MIN. Is (1/3) k
It becomes R. At that time, k needs to satisfy the condition of k> 3. Similarly, when m resistors (1) are connected in parallel, MIN. Is (1 / m) · kR, and k needs to satisfy the condition of k> m. As described above, it is possible to use a unit detection section in which a number of resistors are arranged in parallel, but in actual use, about 2 to 3 may be appropriate.
次に第２図にこの発明の第２の実施例の回路図を示
す。Next, FIG. 2 shows a circuit diagram of a second embodiment of the present invention.
これは第１の実施例に示した抵抗体（１）を２本並列
に接続した単位検知部（２）を更にＮケ直列に接続した
単位検知部群（12）を使用して、同時に複数箇所で油漏
れがあってもその事を検知できるようにしたものであ
る。この時、max.の値は第１の実施例と同様でa,c間の
抵抗値が１つの単位検知部（２）における両方の抵抗体
（１），（１）の破損により、又はリード線部や配線部
の切断等により無限大になった場合に対応して生ずるa,
b間の電位差の値となる。又MIN.の値としては、最小限
の箇所つまり１ケ所において油漏れを検知した時のa,c
間の合成抵抗値を考えればよく、次式（２）で表され
る。This is achieved by simultaneously using a plurality of unit detectors (2) connected in parallel with the two resistors (1) shown in the first embodiment and using a unit detector group (12) connected in N series. Even if there is an oil leak at a location, it can be detected. At this time, the value of max. Is the same as in the first embodiment, and the resistance value between a and c is such that both resistors (1) and (1) in one unit detection section (2) are damaged or lead A, which occurs in response to the infinity caused by cutting the wire or wiring
It becomes the value of the potential difference between b. The values of MIN. Are a and c when oil leakage is detected at the minimum location, that is, at one location.
It is sufficient to consider the combined resistance value between the two, and it is expressed by the following equation (2).
MIN.（２）＝（1/2）・kR＋（1/2）・Ｒ（Ｎ−１） …
（２） 但し、左辺の（ ）内の数字は１つの単位検知部にお
いて並列に接続された抵抗体（１）の個数を示す。MIN. (2) = (1/2) · kR + (1/2) · R (N-1) ...
(2) However, the number in parentheses on the left side indicates the number of resistors (1) connected in parallel in one unit detection unit.
更に各々の単位検知部（２），（２）…を構成する抵
抗体（１），（１）のいずれか１本が切断された時もa,
c間の抵抗値が増大するが、その場合でも油漏れ警報が
誤発生されることが無いようにする必要がある。Further, when any one of the resistors (1) and (1) constituting each unit detection section (2), (2).
Although the resistance value between “c” increases, it is necessary to prevent an erroneous oil leak alarm from being generated even in such a case.
a,c間の抵抗値は一般的に下式（３）で表される。 The resistance value between a and c is generally expressed by the following equation (3).
r(a-c)＝(1/2)・R(N-C)+Σ[｛1/(2-B)｝×R]Ｃ＝１…Ｃ
…（３） r(a-c):a,c間の抵抗 R:抵抗体（１）の通常時の抵抗値 N:単位検知部設置箇所数 C:切断された抵抗体を有する単位検知部の数 B:1つの単位検知部中で切断されている抵抗体の数（今
１つの単位検知部を２本の抵抗体で構成しているのでＢ
＝1or2） ここで（３）式の第２項は、それぞれの切断された抵
抗体を有する単位検知部（１…Ｃ）の合成抵抗を表して
いる。r (ac) = (1/2) R (NC) + {[{1 / (2-B)} x R] C = 1 ... C
... (3) r (ac) : resistance between a and c R: resistance value of resistor (1) at normal time N: number of unit detection unit installation locations C: number of unit detection units having cut resistor B: Number of resistors that are disconnected in one unit detection section (because one unit detection section is composed of two resistors,
= 1 or 2) Here, the second term of the expression (3) represents the combined resistance of the unit detection units (1... C) having the respective disconnected resistors.
このような抵抗体（１）の切断によってa,c間の抵抗
値が最大値をとる場合（無限大は除く）は各単位検知部
（２）を構成する抵抗体（１）が１本ずつ切断されてい
た場合である。すなわち、Ｃ＝ＮでＢ＝１のときであ
る。この条件を（３）式に入れると（３）式は以下の
（４）式の如くなる。When the resistance value between a and c takes the maximum value (except for infinity) due to such cutting of the resistor (1), the resistor (1) constituting each unit detection unit (2) is one by one. This is the case when it has been disconnected. That is, when C = N and B = 1. When this condition is included in the expression (3), the expression (3) becomes the following expression (4).
r(a-c)＝Σ（Ｒ）Ｃ＝１…Ｎ＝RN …（４） 従って、以上の（４）式で表されたa,c間の増大した
最大の抵抗値が、前述の（２）式のMIN.（２）の値より
小さければ抵抗体の切断によって油漏れの誤警報が生ず
ることはない。r (ac) = Σ (R) C = 1... N = RN (4) Therefore, the increased maximum resistance value between a and c expressed by the above equation (4) is the above-mentioned (2) If the value is smaller than the value of MIN. (2) in the equation, no erroneous alarm of oil leakage will be caused by disconnection of the resistor.
∴RN＜MIN.（２） RN＜（1/2）・kR＋（1/2）・Ｒ（Ｎ−１）Ｎ＜ｋ−１…
（５） すなわち（５）式を満足するＮの範囲で単位検知部を
設置すればよい。∴RN <MIN. (2) RN <(1/2) · kR + (1/2) · R (N−1) N <k−1 ...
(5) That is, the unit detection unit may be installed in a range of N satisfying the expression (5).
又第１の実施例で説明したように、唯一の単位検知部
において１本の抵抗体（１）が切断されている場合で
も、もう１本の単位検知部を正常な抵抗体（１）が油分
を検知したときはa,c間の抵抗値は以下の式で表せる。Further, as described in the first embodiment, even when one resistor (1) is cut off in only one unit detecting section, the normal resistor (1) is connected to another unit detecting section. When oil is detected, the resistance between a and c can be expressed by the following equation.
kR＋（1/2）・Ｒ（Ｎ−１） ＝（1/2）・kR＋｛（1/2）・kR＋（1/2）・Ｒ（Ｎ−
１）｝ ＝（1/2）・kR＋（２）式 従って以上の場合にa,c間の抵抗値は（２）式｛＝MI
N.（２）｝より大きくなるため油漏れ警報を発生する。kR + (1/2) · R (N-1) = (1/2) · kR + ｛(1/2) · kR + (1/2) · R (N−
1)｝ = (1/2) · kR + (2) Therefore, in the above case, the resistance value between a and c is given by (2) formula ｛= MI
N. (2) Generates an oil leak alarm because it is larger than｝.
又以上説明した第２の実施例では抵抗体（１）を２本
並列にした単位検知部（２）を複数個（Ｎ個）直列に接
続したものについて説明したが、３本の抵抗体（１）を
並列にした単位検知部（２）を複数個（Ｎ個）直列に接
続した場合もほとんど同様である。In the second embodiment described above, a plurality of (N) unit detection units (2) in which two resistors (1) are arranged in parallel are connected in series, but three resistors (1) are connected in series. This is almost the same when a plurality of (N) unit detection units (2) in which 1) are connected in parallel are connected in series.
すなわちこの時、MIN.（３）は（1/3）・（kR＋Ｒ
（Ｎ−１））となり、r(a-c)の最大値はRNとなるので、 RN＜MIN.（３）を解いて、Ｎの範囲は下記の（６）式で
表さる。That is, at this time, MIN. (3) is (1/3) · (kR + R
(N-1)), and the maximum value of r (ac) is RN. Therefore, RN <MIN. (3) is solved, and the range of N is expressed by the following equation (6).
Ｎ＜（ｋ−１）/2 …（６） すなわち（６）式を満足するＮの範囲で単位検知部を
設置すればよい。尚各単位検知部（２）中の抵抗体
（１）の並列にする個数を変化させても以上と同様にk,
Nの範囲は定まる。N <(k−1) / 2 (6) That is, the unit detection unit may be installed in a range of N satisfying the expression (6). Even if the number of resistors (1) in each unit detector (2) to be arranged in parallel is changed, k,
The range of N is determined.
つまり例えば、ｍ本の抵抗体（１）を並列にした単位
検知部（２）をＮ個直列に接続した場合は、 MIN.（ｍ）＝（1/m）・（kR＋Ｒ（Ｎ−１）） となり、r(a-c)の最大値はRNであるので、RN＜MIN.
（ｍ）を解いて、Ｎの範囲は以下の（７）式で表せる。That is, for example, when N unit detection units (2) in which m resistors (1) are connected in parallel are connected in series, MIN. (M) = (1 / m) · (kR + R (N−1) ), And since the maximum value of r (ac) is RN, RN <MIN.
By solving (m), the range of N can be expressed by the following equation (7).
Ｎ＜（ｋ−１）／（ｍ−１） …（７） すなわち（７）式を満足するＮの範囲で単位検知部を
設置すればよい。N <(k−1) / (m−1) (7) That is, the unit detection unit may be installed in a range of N satisfying the expression (7).
ここで参考のために以上説明した抵抗体（１）として
好適な１つの例としての炭素皮膜型油敏感性抵抗体を第
３図に示す。この構造を簡単に説明すると、油敏感性薄
膜（３）がアルミナ製ボビン（２）に塗布付着させら
れ、リード線（４），（４）等が接続され、さらにたと
えば上記薄膜と同系統の高分子物質よりなる保護膜（図
示しない）で覆われている。FIG. 3 shows a carbon film type oil-sensitive resistor as one preferred example of the resistor (1) described above for reference. Briefly describing this structure, an oil-sensitive thin film (3) is applied to and adhered to an alumina bobbin (2), leads (4), (4) and the like are connected. It is covered with a protective film (not shown) made of a polymer substance.
このような抵抗体は油漏れ検知時の抵抗値の増大割合
が大きく、かつ抵抗値の経年変化が少ないものでなけれ
ばならない。発明者がこれらの用途のために開発した３
種類の炭素皮膜型油敏感性抵抗体（センサー）の抵抗値
変化を第４図に示す。第４図は、重油と接触した後の経
過時間に対するセンサー抵抗値変化を３つのタイプ
（Ａ），（Ｂ），（Ｃ）のセンサーについて比較したカ
ーブA,B,Cを示すものである。Such a resistor must have a large increase rate of the resistance value at the time of oil leak detection and a small change with time in the resistance value. The inventors have developed 3 for these applications.
FIG. 4 shows the change in the resistance value of various types of carbon film type oil-sensitive resistors (sensors). FIG. 4 shows curves A, B, and C in which changes in sensor resistance value with respect to elapsed time after contact with heavy oil are compared for three types of sensors (A), (B), and (C).
炭素皮膜型油敏感性抵抗体の特性は油敏感性薄膜
（３）に使用する親油性で且つ撥水性の高分子物質の種
類、炭素微粒粉末の粒度と添加量、薄膜の膜厚及び電極
間距離等によって調整されて、測定対象油種などの用途
目的に応じ、使い分けられる。第４図のカーブＡに示す
タイプ（Ａ）は保護膜を薄くして高感度化したもの、同
カーブＢに示すタイプ（Ｂ）は炭素皮膜を薄くして高感
度化したもの、同カーブＣに示すタイプ（Ｃ）は電極間
距離を短くし、かつ炭素皮膜を厚くすることによって高
感度化したものである。The characteristics of the carbon film type oil-sensitive resistor include the type of lipophilic and water-repellent polymer substance used for the oil-sensitive thin film (3), the particle size and amount of carbon fine powder, the film thickness of the thin film, and the distance between electrodes. It is adjusted according to the distance and the like, and is properly used according to the purpose of use such as the type of oil to be measured. The type (A) shown in the curve A of FIG. 4 has a higher sensitivity by making the protective film thinner, the type (B) shown in the same curve B has the higher sensitivity by making the carbon film thinner, and the curve C has the same. In the type (C) shown in Fig. 7, the sensitivity is increased by shortening the distance between the electrodes and increasing the thickness of the carbon film.
今、炭素皮膜型油敏感性抵抗体としてタイプ（Ｃ）を
選んだとき。センサー抵抗値の初期値がＲ＝10kΩとし
たとき、油と接触して５秒後にはその抵抗値は100kΩ
に、つまりｋ値は10に、又10秒後には170kΩに、つまり
ｋ値は17となる。また他のタイプ（Ａ）を選んだときは
５秒後40kΩ（ｋ値:4）、10秒後には60kΩ（ｋ値:6）と
なり、又タイプ（Ｂ）を選んだときには５秒後55kΩ
（ｋ値:5.5）、10秒後には100kΩ（ｋ値:10）となる。Now, when type (C) is selected as a carbon film type oil sensitive resistor. When the initial value of the sensor resistance value is R = 10 kΩ, the resistance value is 100 kΩ after 5 seconds from contact with the oil.
The k value is 10, and after 10 seconds it is 170 kΩ, ie the k value is 17. When another type (A) is selected, 40 kΩ (k value: 4) after 5 seconds, 60 kΩ (k value: 6) after 10 seconds, and 55 kΩ after 5 seconds when type (B) is selected.
(K value: 5.5), and after 10 seconds, 100 kΩ (k value: 10).
このようにタイプ（Ａ），（Ｂ），（Ｃ）とも重油接
触後の経過時間の長時間化が許される限り、単位検知部
をシリーズに数多く接続することが可能になる。As described above, in each of the types (A), (B), and (C), as long as the elapse of time after contact with heavy oil is allowed, a large number of unit detection units can be connected to the series.
例えば、抵抗体を２本並列にした単位検知部を８ケ直
列に接続した場合のｋ値は（６）式からｋ＞2N＋１＝17
を満足するものでなければならない。即ち油を検知した
時のセンサー抵抗値が初期値を10kΩとすれば170kΩ以
上のものでなければ使用できない。油と接触後10から20
秒の間でこの条件を満足するセンサーはタイプ（Ｃ）で
ある。仮にタイプ（Ｂ）を選択する場合は油との接触後
の経過時間は30秒以上、タイプ（Ａ）の場合は60秒以上
と、検出が長時間化する。For example, when eight unit detection units each having two resistors connected in parallel are connected in series, the k value is k> 2N + 1 = 17 from the equation (6).
Must be satisfied. That is, if the initial value of the sensor resistance value when detecting oil is 10 kΩ, it cannot be used unless it is 170 kΩ or more. 10 to 20 after contact with oil
Sensors that satisfy this condition in seconds are type (C). If type (B) is selected, the elapsed time after contact with oil is 30 seconds or longer, and if type (A) is 60 seconds or longer, detection is prolonged.
尚、以上の例ではブリッジ回路を利用した検知回路を
示したが、第５図に示すように電流測定器（13）と比較
器（11）を利用した電流測定回路によって検知回路を構
成しても同様の効果を奏する。従って測定対象の油種、
測定場所、使用目的に応じてこれらのブリッジ回路と電
流測定回路を適宜使い分ける事が望ましい。In the above example, the detection circuit using the bridge circuit is shown. However, as shown in FIG. 5, the detection circuit is configured by the current measurement circuit using the current measuring device (13) and the comparator (11). Has the same effect. Therefore, the oil type to be measured,
It is desirable to appropriately use these bridge circuits and current measurement circuits depending on the measurement place and the purpose of use.
又実質的に同じ抵抗値をもつ２本の抵抗体にそれぞれ
例えば低抵抗値の温度特性補償素子などを直列に挿入し
たものを二個並列に接続するなどの接続方法も含めて実
質的に並列と称することとする。A substantially parallel connection is also possible, including a connection method in which, for example, two resistors each having a resistance value and a temperature characteristic compensating element having a low resistance value inserted in series are connected in parallel to two resistors having substantially the same resistance value. Shall be referred to as
以上のように、本発明の請求項（１）の油漏れ検知方
法によれば、油漏れ検知時に抵抗値が通常時の抵抗値Ｒ
のｋ倍に変化する抵抗体をｍ（２≦ｍ＜ｋ）個並列に接
続して、その合成抵抗値が（1/m）・kR以上に変化した
時に油漏れ警報を発生する。従ってｍ個の抵抗体のうち
ｍ−１個の抵抗体が切断又はリード線切れ等によって破
損しても、誤って油漏れ警報を発生することがなくか
つ、少なくとも１つの抵抗体が破損等していない限り、
油漏れ検知時に油漏れ警報を発生することが可能となっ
ている。As described above, according to the oil leakage detection method of the present invention, the resistance value when the oil leakage is detected is the normal resistance value R.
M (2 ≦ m <k) resistors are connected in parallel, and an oil leak alarm is generated when the combined resistance value changes to (1 / m) · kR or more. Therefore, even if m-1 resistors out of the m resistors are broken due to cutting or broken lead wires, an oil leak alarm is not erroneously generated and at least one of the resistors is damaged. Unless
It is possible to generate an oil leak alarm when an oil leak is detected.
本発明の請求項（２）の油漏れ検知方法によれば、油
漏れ検知時に抵抗値が通常時の抵抗値Ｒのｋ倍に変化す
る抵抗体をｍ（２≦ｍ＜ｋ）個並列に接続した単位検知
部を更にＮ（＜（ｋ−１）／（ｍ−１））個直列に接続
して、その全体の合成抵抗値が（1/m）・（kR＋Ｒ（Ｎ
−１））以上に変化した時に油漏れ警報を発生する。従
って、各々の単位検知部においてｍ−１個の抵抗体が切
断又はリード線切れ等によって破損しても、誤って油漏
れ警報を発生することがなくかつ、各単位検知部におい
て少なくとも１つの抵抗体が破損等していない限り、最
小１箇所の単位検知部での油漏れ検知時に、油漏れ警報
を発生することが可能となっている。According to the oil leak detection method of claim 2 of the present invention, m (2 ≦ m <k) resistors whose resistance changes k times the normal resistance R at the time of oil leak detection are connected in parallel. N (<(k−1) / (m−1)) connected unit detection units are further connected in series, and the total combined resistance value is (1 / m) · (kR + R (N
-1)) Generates an oil leak alarm when the above changes occur. Therefore, even if the m-1 resistors in each unit detector are broken due to a cut or a broken lead wire, an oil leak alarm is not erroneously generated and at least one resistor is detected in each unit detector. As long as the body is not damaged, it is possible to generate an oil leak alarm when oil leak is detected by at least one unit detection unit.
第１図はこの発明の実施に使用する油漏れ検知器駆動回
路、第２図はこの発明の実施に使用する他の油漏れ検知
器駆動回路、第３図は炭素皮膜型油敏感性抵抗体の構造
図、第４図は重油と接触後のセンサー抵抗値変化を示す
グラフ、第５図はこの発明の実施に使用する他の油漏れ
検知器駆動回路、第６図は従来の油漏れ検知器駆動回路
である。 図中、１は抵抗体、２は単位検知部、R1,R2,R3は抵抗
器、Ｅは電源、11は比較器、12は単位検知部群である。FIG. 1 is an oil leak detector drive circuit used in the embodiment of the present invention, FIG. 2 is another oil leak detector drive circuit used in the embodiment of the present invention, and FIG. 3 is a carbon film type oil sensitive resistor. FIG. 4 is a graph showing a change in resistance of the sensor after contact with heavy oil, FIG. 5 is another drive circuit for an oil leak detector used in the embodiment of the present invention, and FIG. It is a device drive circuit. In the figure, 1 is the resistor, 2 units detecting unit, R 1, R 2, R 3 resistors, E is the power supply, 11 is a comparator, 12 is a unit detecting portion group.
Claims (4)
る実質的に同じ抵抗値の抵抗体をｍ（２≦ｍ＜ｋ）個実
質的に並列に接続し、その並列に接続した抵抗体の合成
抵抗値が（1/m）・kR以上kR以下に変化した時、油漏れ
警報を発生する油漏れ検知方法。When detecting an oil leak, m (2 ≦ m <k) resistors having substantially the same resistance whose resistance R changes to kR are connected in parallel and connected in parallel. An oil leak detection method that generates an oil leak alarm when the combined resistance value of the changed resistor changes from (1 / m) · kR to kR.
る実質的に同じ抵抗値の抵抗体をｍ（２≦ｍ＜ｋ）個実
質的に並列に接続してなる単位検知部をＮ（＜（ｋ−
１）／（ｍ−１））個直列に接続し、そのＮ個の抵抗体
の合成抵抗値が（1/m）・（kR＋Ｒ（Ｎ−１））以上kRN
以下に変化した時に油漏れ警報を発生する油漏れ検知方
法。2. A unit detection unit comprising m (2 ≦ m <k) resistors having substantially the same resistance value whose resistance value R changes to kR when oil leakage is detected, which are connected in parallel. To N (<(k−
1) / (m-1)) resistors are connected in series, and the combined resistance value of the N resistors is (1 / m) · (kR + R (N−1)) or more and kRN
An oil leak detection method that generates an oil leak alarm when the following changes occur.
る実質的に並列に接続された実質的に同じ抵抗値のｍ
（２≦ｍ＜ｋ）個の抵抗体、 前記並列に接続された抵抗体の合成抵抗値を測定する抵
抗測定手段、 前記抵抗測定手段の抵抗測定値が（1/m）・kR以上kR以
下に変化した場合、油漏れ警報を発生する比較手段、 を具備する油漏れ検知器。3. When an oil leak is detected, its resistance R changes to kR.
(2 ≦ m <k) resistors, a resistance measuring means for measuring a combined resistance value of the resistors connected in parallel, and a resistance measured value of the resistance measuring means being (1 / m) · kR or more and kR or less. An oil leak detector that generates an oil leak alarm when the oil leak detector changes to
る実質的に並列に接続された実質的に同じ抵抗値のｍ
（２≦ｍ＜ｋ）個の抵抗体よりなる単位検知部がＮ（＜
（ｋ−１）／（ｍ−１）個直列に接続されたその単位検
知群、 前記単位検知群の合成抵抗値を測定する抵抗測定手段、 前記抵抗測定手段の抵抗測定値が（1/m）・（kR＋Ｒ
（Ｎ−１））以上kRN以下に変化した場合、油漏れ警報
を発生する比較手段、 を具備する油漏れ検知器。4. When an oil leak is detected, the resistance value R changes to kR.
The unit detection unit composed of (2 ≦ m <k) resistors is N (<
(K-1) / (m-1) unit detection groups connected in series, a resistance measuring means for measuring a combined resistance value of the unit detection group, and a resistance measurement value of the resistance measuring means being (1 / m ) ・ (KR + R
(N-1)) a comparison means for generating an oil leak alarm when the value changes from kRN to kRN.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2064723A JP2597028B2 (en) | 1990-03-14 | 1990-03-14 | Oil leak detection method and detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2064723A JP2597028B2 (en) | 1990-03-14 | 1990-03-14 | Oil leak detection method and detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03264854A JPH03264854A (en) | 1991-11-26 |
| JP2597028B2 true JP2597028B2 (en) | 1997-04-02 |
Family
ID=13266361
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2064723A Expired - Lifetime JP2597028B2 (en) | 1990-03-14 | 1990-03-14 | Oil leak detection method and detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2597028B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102539077A (en) * | 2012-01-02 | 2012-07-04 | 税爱社 | Big tank statistics-compiling material balance leak detecting method and leak detecting system |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6883382B2 (en) * | 2015-10-05 | 2021-06-09 | スリーエム イノベイティブ プロパティズ カンパニー | Leakage detector |
-
1990
- 1990-03-14 JP JP2064723A patent/JP2597028B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102539077A (en) * | 2012-01-02 | 2012-07-04 | 税爱社 | Big tank statistics-compiling material balance leak detecting method and leak detecting system |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03264854A (en) | 1991-11-26 |
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