JPS6239940B2 - - Google Patents
Info
- Publication number
- JPS6239940B2 JPS6239940B2 JP2144582A JP2144582A JPS6239940B2 JP S6239940 B2 JPS6239940 B2 JP S6239940B2 JP 2144582 A JP2144582 A JP 2144582A JP 2144582 A JP2144582 A JP 2144582A JP S6239940 B2 JPS6239940 B2 JP S6239940B2
- Authority
- JP
- Japan
- Prior art keywords
- humidity sensor
- temperature compensation
- temperature
- sensor element
- heating
- 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
Links
- 238000004140 cleaning Methods 0.000 claims description 21
- 238000010438 heat treatment Methods 0.000 claims description 17
- 238000000034 method Methods 0.000 claims description 8
- 238000010586 diagram Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 1
- 230000007423 decrease Effects 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
- G01N27/121—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 for determining moisture content, e.g. humidity, of the fluid
Description
【発明の詳細な説明】
本発明は加熱クリーニング機構により湿度セン
サ素子の汚れを焼き切るタイプの湿度センサのク
リーニング方法に関し、その目的とするところは
正確に湿度センサ素子の加熱温度を検出できる方
法を提供することにある。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cleaning a humidity sensor of the type that burns off dirt on a humidity sensor element using a heating cleaning mechanism, and its purpose is to provide a method that can accurately detect the heating temperature of a humidity sensor element. It's about doing.
第１図は従来のクリーニング状態を示し、１は
湿度センサ素子２とサーミスタ等の温度補償要素
３とを直列接続して成る湿度センサで、湿度セン
サ素子２の温度特性を温度補償要素３で補償して
接続点Ｊの分圧電圧Vsを計測して湿度情報が検
出される。４は湿度センサ素子２の近傍に配設さ
れたクリーニング用ヒータである。 FIG. 1 shows a conventional cleaning state, where 1 is a humidity sensor consisting of a humidity sensor element 2 and a temperature compensation element 3 such as a thermistor connected in series, and the temperature characteristic of the humidity sensor element 2 is compensated by the temperature compensation element 3. Humidity information is detected by measuring the partial voltage Vs at the connection point J. Reference numeral 4 denotes a cleaning heater disposed near the humidity sensor element 2.
前記湿度センサ素子２は高温領域においてサー
ミスタ特性を示すため、従来の加熱クリーニング
は、ヒータ４で湿度センサ素子２を加熱クリーニ
ングに必要な400℃〜500℃に加熱し、湿度センサ
素子２の抵抗値が低下して前記分圧電圧Vsが所
定電圧を上回つた時にヒータ４への通電をオフす
ることにより行われている。 Since the humidity sensor element 2 exhibits thermistor characteristics in a high temperature range, conventional heating cleaning involves heating the humidity sensor element 2 to 400°C to 500°C, which is necessary for heating cleaning, using a heater 4 to reduce the resistance value of the humidity sensor element 2. This is done by turning off the power to the heater 4 when the voltage Vs decreases and the divided voltage Vs exceeds a predetermined voltage.
しかしながら、湿度センサ素子２が置かれてい
る雰囲気の温度〔正確には温度補償要素３が置か
れている雰囲気の温度〕が変ることにより、温度
補償要素３の抵抗値も変化するため、前記分圧電
圧Vsからは湿度センサ素子２の加熱温度を正確
に測れていないのが現状である。即ち、このよう
な従来の方法によると、低温の場合と高温の場合
とでは、湿度センサ素子２が同一温度でクリーニ
ングされず、クリーニング温度が低過ぎたり、高
過ぎたりするものである。クリーニング温度が低
過ぎると、湿度センサ素子２の汚れが十分に焼き
切れずに汚れが蓄積して精度を悪くしたり、信頼
性が低下し、またクリーニング温度が高過ぎると
湿度センサ素子２の寿命を短かくしたり、過度の
時には湿度センサ素子２を破壊に到らしめるもの
である。 However, as the temperature of the atmosphere in which the humidity sensor element 2 is placed (more precisely, the temperature of the atmosphere in which the temperature compensation element 3 is placed) changes, the resistance value of the temperature compensation element 3 also changes. Currently, the heating temperature of the humidity sensor element 2 cannot be accurately measured from the piezoelectric voltage Vs. That is, according to such a conventional method, the humidity sensor element 2 is not cleaned at the same temperature when the temperature is low or high, and the cleaning temperature is either too low or too high. If the cleaning temperature is too low, the dirt on the humidity sensor element 2 will not be sufficiently burned off and dirt will accumulate, impairing accuracy and reliability, and if the cleaning temperature is too high, the life of the humidity sensor element 2 will be shortened. If the humidity is too short or excessive, the humidity sensor element 2 may be destroyed.
そこで本発明のクリーニング方法は、湿度セン
サ素子と直列に温度補償要素を接続し、前記湿度
センサ素子と前記温度補償要素との接続点の電位
から湿度を検出するよう構成された湿度センサの
クリーニングに際し、前記湿度センサ素子を加熱
すると共に温度補償要素による前記接続点の電位
の温度補償を禁止し、前記接続点の電位から湿度
センサ素子の加熱温度を検出して、湿度センサ素
子の加熱温度が雰囲気温度に左右されないように
したものであつて、以下本発明の具体的な一実施
例を第２図に基づいて説明する。なお、第１図と
同様の作用を成すものには同一符号を付けてその
説明を省く。 Therefore, the cleaning method of the present invention includes a temperature compensation element connected in series with a humidity sensor element, and humidity sensor configured to detect humidity from a potential at a connection point between the humidity sensor element and the temperature compensation element. , heating the humidity sensor element and prohibiting temperature compensation of the potential of the connection point by the temperature compensation element, detecting the heating temperature of the humidity sensor element from the potential of the connection point, and adjusting the heating temperature of the humidity sensor element to the ambient temperature. A specific embodiment of the present invention, which is not affected by temperature, will be described below with reference to FIG. Components having the same functions as those in FIG. 1 are given the same reference numerals and their explanations will be omitted.
５は温度補償要素３のとり得る抵抗値の最小値
よりも十分小さな抵抗値の固定抵抗器で、トラン
ジスタ６を介して温度補償要素３と並列に接続さ
れている。７はトランジスタ６のスイツチングを
制御する駆動回路で、クリーニング時には端子８
が論理レベル“Ｈ”に引き上げられる。 A fixed resistor 5 has a resistance value sufficiently smaller than the minimum resistance value that the temperature compensation element 3 can take, and is connected in parallel with the temperature compensation element 3 via a transistor 6. 7 is a drive circuit that controls switching of transistor 6, and terminal 8 is connected during cleaning.
is pulled to logic level "H".
このように構成したため、クリーニングに際し
て前記端子８が論理レベル“Ｈ”にセツトされる
と、インバータ９を介してトランジスタ１０が
ON状態となり、前記トランジスタ６のベースに
高レベル電位が印加されてトランジスタがON状
態となる。これによつて、温度補償要素３に前記
固定抵抗器５が並列接続されて、温度補償要素３
による前記分圧電圧Vsの温度補償が禁止され、
分圧電圧Vsから湿度センサ素子２の加熱温度が
正しく計測できるため、周囲温度によつて加熱ク
リーニング温度が異なることがない。 With this configuration, when the terminal 8 is set to logic level "H" during cleaning, the transistor 10 is turned on via the inverter 9.
The transistor 6 is turned on, and a high level potential is applied to the base of the transistor 6, turning the transistor on. As a result, the fixed resistor 5 is connected in parallel to the temperature compensation element 3, and the temperature compensation element 3 is connected in parallel with the fixed resistor 5.
Temperature compensation of the divided voltage Vs is prohibited by
Since the heating temperature of the humidity sensor element 2 can be accurately measured from the partial voltage Vs, the heating cleaning temperature does not vary depending on the ambient temperature.
今、一例として温度補償要素３として100KΩ
で温度定数〔Ｂ定数とも云う〕が4000のサーミス
タを使用したとする。また、湿度センサの使用温
度領域を０℃〜100℃とすると、温度補償要素３
の抵抗値は約7KΩ〜340KΩにわたつて変化す
る。この場合、前記固定抵抗器５として抵抗値が
1KΩのものを用いれば、雰囲気温度０℃〜100℃
の加熱クリーニングに及ぼす影響がほとんどなく
なることがわかる。 Now, as an example, temperature compensation element 3 is 100KΩ.
Assume that a thermistor with a temperature constant (also called B constant) of 4000 is used. In addition, if the operating temperature range of the humidity sensor is 0°C to 100°C, the temperature compensation element 3
The resistance value varies from about 7KΩ to 340KΩ. In this case, the resistance value of the fixed resistor 5 is
If you use a 1KΩ one, the ambient temperature will be between 0°C and 100°C.
It can be seen that the influence on heating cleaning is almost eliminated.
以上説明のように本発明の湿度センサの加熱ク
リーニング法によると、湿度センサの使用温度領
域の全ての範囲で一定な加熱クリーニングが行え
るため、湿度センサは広い使用温度範囲において
高精度、高信頼性を有することになり、実用上き
わめて有用なものである。 As explained above, according to the heating cleaning method for a humidity sensor of the present invention, constant heating cleaning can be performed over the entire operating temperature range of the humidity sensor, so the humidity sensor has high accuracy and high reliability over a wide operating temperature range. Therefore, it is extremely useful in practice.
第１図は従来のクリーニング方法の説明図、第
２図は本発明のクリーニング方法の具体的な一実
施例の説明図である。
２…湿度センサ素子、３…温度補償要素、４…
ヒータ、５…固定抵抗器。
FIG. 1 is an explanatory diagram of a conventional cleaning method, and FIG. 2 is an explanatory diagram of a specific embodiment of the cleaning method of the present invention. 2... Humidity sensor element, 3... Temperature compensation element, 4...
Heater, 5...Fixed resistor.
Claims (1)
し、前記湿度センサ素子と前記温度補償要素との
接続点の電位から湿度を検出するよう構成された
湿度センサのクリーニングに際し、前記湿度セン
サ素子を加熱すると共に温度補償要素による前記
接続点の電位の温度補償を禁止し、前記接続点の
電位から湿度センサ素子の加熱温度を検出する湿
度センサの加熱クリーニング法。 ２ 温度補償要素による温度補償動作の禁止を、
温度補償要素と並列に前記温度補償要素に比べて
十分小さな抵抗値の固定抵抗器を接続して行う特
許請求の範囲第１項記載の湿度センサの加熱クリ
ーニング法。[Claims] 1. When cleaning a humidity sensor configured to connect a temperature compensation element in series with a humidity sensor element and detect humidity from a potential at a connection point between the humidity sensor element and the temperature compensation element, A heating cleaning method for a humidity sensor, which heats the humidity sensor element, prohibits temperature compensation of the potential at the connection point by a temperature compensation element, and detects the heating temperature of the humidity sensor element from the potential at the connection point. 2 Prohibition of temperature compensation operation by temperature compensation element,
2. The heating cleaning method for a humidity sensor according to claim 1, which is carried out by connecting a fixed resistor having a sufficiently smaller resistance value than the temperature compensation element in parallel with the temperature compensation element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2144582A JPS58139058A (en) | 1982-02-12 | 1982-02-12 | Cleaning method for humidity sensor by heating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2144582A JPS58139058A (en) | 1982-02-12 | 1982-02-12 | Cleaning method for humidity sensor by heating |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58139058A JPS58139058A (en) | 1983-08-18 |
| JPS6239940B2 true JPS6239940B2 (en) | 1987-08-26 |
Family
ID=12055158
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2144582A Granted JPS58139058A (en) | 1982-02-12 | 1982-02-12 | Cleaning method for humidity sensor by heating |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58139058A (en) |
-
1982
- 1982-02-12 JP JP2144582A patent/JPS58139058A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58139058A (en) | 1983-08-18 |
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