JPS58160856A - Humidity detector - Google Patents

Abstract

PURPOSE:To make the temperature compensation of a humidity sensitive element and to obtain the relation of uniform correspondence between relative humidity and an output of a bridge circuit, by providing the bridge circuit having the humidity sensitive element which performs physical change by temperature and a temperature sensitive element provided in the neighborhood of the humidity sensitive element and performe physical change by the temperature on two sides. CONSTITUTION:A negative characteristic thermistor is used for a temperature sensitive element TH1 and a humidity sensitive element RH is constituted by a bridge circuit together with the element TH1 positioned to the opposite side and resistances R1, R2 and then, this element TH1 is provided in the neighborhood of the element RH. Accordingly, a temperature characteristic of the element RH is corrected in the bridge circuit by using the temperature characteristic of the element TH1 and the relation of uniform correspondence is obtained between relative humidity and an output e0 by a differential amplifier A.

Description

【発明の詳細な説明】 本発明は相対湿度により抵抗値の変化するｓ＆１素子を
用いた湿度検出器に係り、特に感温素子に温度補償を施
したものであるっ 一般に高分子８Ｍ素子の相対湿度、湿度、抵抗値の間に
は第１図に示す如き特性があることが知られているっす
なわち、相対湿度が増加すると抵抗値が減少する特性を
もち、合わせて温度が増加しても抵抗値が減少する特性
をもっているっ従って、相対湿度が一定でも温度が異な
ると異なる抵抗値を示すっ言い換えると、抵抗値が一定
でも温度が異なると異なる相対湿度を示すことになるう
このように、温度条件により相対軽度と抵抗値とが一意
対応しない特性を何しているう無層、ある所定の相対軽
度のみを検出して加湿器、除Ｍ器等を０Ｎ−ＯＦＦ制御
する場合には感温素子の使用原作における麺皮変化が比
較的に小さいため、適当な固定抵抗等を付加するのみで
ある程度の温度補償が行えるものの、複数の近接した相
対湿度を検出しようとすると温度による影響が大さく作
用し、誤動作による弊害をまねくものであったっ そこで、第２図（イ）（ロ）に示す如く温度特性を有す
る感ＩｊＡ素子（ＴＨ）を感湿素子（ＲＨ）と直列もし
くは並列に接続して直接温度補償を行なうなどが試みら
れたが、感温素子（ＴＨ）の抵抗値が物性上感湿素子（
ＲＨ）の抵抗値に比べて小さいため第２図（イ）の場合
には温度補正の範囲が狭いものとなり、第２図（ロ）の
場合には合成インピーダンスが小さくなりマツチングが
悪くなるなどの欠点をもっていたつ 本発明は祈る欠点に饋みてなされ、広い温度範囲におい
て＃８湿素子の温度補償を行なうことを目的としたもの
であり、温度により物理的な変化をする感湿素子と、感
湿素子の近傍に配設され温度シでより物理的な変化をす
る感温素子とを二辺に有するブリッジ回路を設けること
により感湿素子の泥炭補償を行ない、相対す度とブリッ
ジ回路の出力との間に一意対応の関係を得るようにした
ものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a humidity detector using an S&1 element whose resistance value changes depending on relative humidity, and in particular, a humidity sensor in which a temperature-sensitive element is temperature-compensated. It is known that there is a characteristic between humidity, humidity, and resistance value as shown in Figure 1. In other words, when the relative humidity increases, the resistance value decreases, and even when the temperature increases, the resistance value decreases. It has the characteristic that the resistance value decreases. Therefore, even if the relative humidity is constant, it will show a different resistance value when the temperature changes. In other words, even if the resistance value is constant, it will show a different relative humidity when the temperature changes. When detecting only a certain relative lightness and controlling the humidifier, M remover, etc. to ON-OFF, there is a characteristic that the relative lightness and resistance value do not correspond uniquely depending on the temperature condition. Using a thermosensor Since the change in the noodle skin in the original work is relatively small, it is possible to compensate for the temperature to a certain extent by simply adding an appropriate fixed resistor, but if you try to detect multiple relative humidities in close proximity, the effect of temperature will increase. Therefore, as shown in Figure 2 (a) and (b), a temperature-sensitive IjA element (TH) with temperature characteristics was connected in series or parallel with a humidity-sensitive element (RH). Attempts have been made to directly compensate for temperature by connecting the temperature sensitive element (TH), but due to physical properties, the resistance value of the temperature sensing element (TH) is higher than that of the moisture sensing element (TH).
In the case of Figure 2 (a), the range of temperature correction is narrow, and in the case of Figure 2 (b), the combined impedance is small and the matching becomes poor. The present invention, which had its drawbacks, has been made to address the drawbacks and aims to compensate for the temperature of the #8 humidity element over a wide temperature range. Peat compensation for the humidity sensing element is performed by providing a bridge circuit on two sides with a temperature sensing element that is placed near the humidity element and has a temperature sensing element that changes physically depending on the temperature, and the relative temperature and output of the bridge circuit are This is to obtain a unique correspondence relationship between .

以下、本発明の一実施例を第６図に基ついて説明すると
、感温素子（ＴＨＥ）として負特性サーミスタを用いて
おり、（ＲＨ）は対辺に位置するｂ＃Ａ素子（ＴＨＥ）
と抵抗（Ｒ１）、（Ｒ２）と共にブリッジ回路を構成す
る感湿素子であり、この感＃Ａｉｆｉ子（ＴＨＥ）は１
８昼素子（ＲＨ）の近傍に配設されているっまた、囚、
（Ｒ５）はブリッジ回路の出力′を増幅する差動増幅器
および帰還抵抗であろう従って、８Ｍ素子（ＲＨ）の温
′度特性を感湿素子（ＴＨＥ）の温度特性を用いてブリ
ッジ回路内で補正し差動増幅器（３）より第６図に示す
如き相対経度と出力（ｅｏ）との間に一意対応の関係を
得ることができる。Hereinafter, one embodiment of the present invention will be explained based on FIG. 6. A negative characteristic thermistor is used as the temperature sensing element (THE), and (RH) is the b#A element (THE) located on the opposite side.
It is a moisture sensing element that constitutes a bridge circuit together with resistors (R1) and (R2), and this sensing element (THE) is 1
8. There is also a prisoner located near the daylight element (RH).
(R5) is a differential amplifier and feedback resistor that amplifies the output of the bridge circuit. Therefore, the temperature characteristics of the 8M element (RH) can be calculated within the bridge circuit using the temperature characteristics of the moisture sensing element (THE). Through the correction and differential amplifier (3), a unique correspondence relationship between the relative longitude and the output (eo) as shown in FIG. 6 can be obtained.

壱→Ｆも舎−← 第４図、第５図は感湿素子（ＴＨｌ）として正特性サー
ミスタを用いた他の実施例であり、（ＲＨ）は隣辺に位
置する感温素子（ＴＨｌ）と抵抗（Ｒ１）、（Ｒ２）と
共にブリッジ回路を構成する感温素子であり、この感温
素子（ＴＨｌは感湿素子（ＲＨ）の近傍に配設されてい
るっまた、（Ａ）、（Ｒ５）はブリッジ回路の出力を増
幅する差動増幅器および帰還抵抗であろう 従って、上記と同様に第６図の如き関係を得ることがで
きろう ゛またグリッジ回路の出力を差動の対数増幅器に入力す
ると線形出力を得ることが口Ｉ能であり、さらにグリッ
ジ回路の出力を比較器に入力し所定の相対湿度で出力を
切換えることも＝Ｊ能であるっなうことができ、相対湿
度と感湿素子の抵抗値と　　　　　；！の闇に一意対応
の関係をもつ出力を得ることかできるなど極めて効果の
太さいものであるっ1 → F Mosha - ← Figures 4 and 5 show other embodiments in which a positive temperature coefficient thermistor is used as the moisture sensing element (THl), and (RH) is the temperature sensing element (THl) located on the adjacent side. It is a temperature sensing element that constitutes a bridge circuit together with resistors (R1) and (R2), and this temperature sensing element (THl) is arranged near the humidity sensing element (RH). R5) is a differential amplifier that amplifies the output of the bridge circuit and a feedback resistor.Therefore, similarly to the above, we can obtain the relationship shown in Figure 6.Also, if we connect the output of the bridge circuit to a differential logarithmic amplifier, we can obtain the relationship shown in Figure 6. It is a function to obtain a linear output when inputting an input, and it is also a function to input the output of the glitch circuit to a comparator and switch the output at a predetermined relative humidity. It is extremely effective, as it is possible to obtain an output that has a unique correspondence between the resistance value of the humidity sensing element and the darkness of ;!

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は＆８湿素子の一例を示す特性図、第２図（イ）
、（ロ）は本発明改良前の電気回路図、第５図は本発明
の一実施例を示す電気回路図、第４図、第５図は本発明
の他の実施例を示す電気回路図、第６図は第６図乃至第
５図の端子（ｅｏ　）における出力図であるっ （ＲＨ）・・・感湿素子、（ＴＨＥ）、（ＴＨｌ）・・
・感温素子っ 裟曇呵＜ＲＨ 第２図 ｃｃ 第３１４１ ｃｃFigure 1 is a characteristic diagram showing an example of &8 wet element, Figure 2 (a)
, (b) are electric circuit diagrams before the improvement of the present invention, FIG. 5 is an electric circuit diagram showing one embodiment of the present invention, and FIGS. 4 and 5 are electric circuit diagrams showing other embodiments of the present invention. , FIG. 6 is an output diagram at the terminal (eo) in FIGS. 6 to 5 (RH)...moisture sensing element, (THE), (THl)...
・Temperature sensing element cloud <RH Figure 2 cc No. 3141 cc

Claims (1)

【特許請求の範囲】[Claims] （１）　　湿度により物理的な変化をする感湿素子と、
該感温素子の近傍に配設され温度により物理的な変化を
する感温素子とをブリッジ回路の二辺に設けたことを特
徴とする軽度検出器。(1) A moisture-sensitive element that physically changes depending on humidity;
1. A light-duty detector characterized in that temperature-sensitive elements that are arranged near the temperature-sensitive element and physically change depending on temperature are provided on two sides of a bridge circuit.