JP2885581B2 - Temperature and humidity detection circuit - Google Patents
Temperature and humidity detection circuitInfo
- Publication number
- JP2885581B2 JP2885581B2 JP22888792A JP22888792A JP2885581B2 JP 2885581 B2 JP2885581 B2 JP 2885581B2 JP 22888792 A JP22888792 A JP 22888792A JP 22888792 A JP22888792 A JP 22888792A JP 2885581 B2 JP2885581 B2 JP 2885581B2
- Authority
- JP
- Japan
- Prior art keywords
- temperature
- sensitive
- resistor
- humidity
- resistance
- 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.)
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- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Description
【0001】[0001]
【産業上の利用分野】本発明は温湿度検出回路に関し、
詳しくは、特に加熱調理装置の絶体湿度及び温度検出を
兼用する温湿度検出回路に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature and humidity detecting circuit,
More particularly, the present invention relates to a temperature / humidity detection circuit that also serves to detect the absolute humidity and temperature of a cooking device.
【0002】[0002]
【従来の技術】図6は従来例1の湿度検出回路である。
図6に示すように、Rsは湿気を含む雰囲気に暴露され
湿度変化を検出する第1感温抵抗素子、Rrはその雰囲
気の温度変化を検出する第2感温抵抗素子、A1はオペ
アンプ、R1、R2は固定抵抗である。Evはこの湿度検
出回路に供給される直流定電圧であり、Eoは固定抵抗
R 1、R2で決定される基準電圧である。Io(=Eo/R
r)は第1感温抵抗素子Rs及び第2感温抵抗素子Rr に
流れる電流値である。この時の絶対湿度値を示す出力V
out は次式で示される。 Vout =(1+Rs/Rr)×Eo2. Description of the Related Art FIG. 6 shows a humidity detection circuit of a first conventional example.
As shown in FIG. 6, Rs was exposed to an atmosphere containing moisture.
The first temperature-sensitive resistance element for detecting a change in humidity, Rr, represents the atmosphere.
A second temperature-sensitive resistance element for detecting a temperature change of air, A1Is an operation
Amplifier, R1, RTwoIs a fixed resistance. Ev is the humidity detection
DC constant voltage supplied to the output circuit, Eo is a fixed resistance
R 1, RTwoIs the reference voltage determined by Io (= Eo / R
r) corresponds to the first temperature-sensitive resistor Rs and the second temperature-sensitive resistor Rr.
It is the value of the flowing current. Output V indicating absolute humidity value at this time
out is represented by the following equation. Vout = (1 + Rs / Rr) × Eo
【0003】図7は従来例2の湿度検出回路である。図
7に示すように、図6の回路にオペアンプA2、固定抵
抗R3〜R5で構成される演算増幅回路を追加した例であ
り、この時の絶対湿度値を示す出力Voutは次式で示さ
れる。 Vout =−(Rs/Rr)×(R5/R3)×Eo +(1+R5/
R4)×EoFIG. 7 shows a humidity detection circuit of a second conventional example. As shown in FIG. 7, this is an example in which an operational amplifier composed of an operational amplifier A 2 and fixed resistors R 3 to R 5 is added to the circuit of FIG. 6. The output Vout indicating the absolute humidity value at this time is expressed by the following equation. Indicated by Vout = − (Rs / Rr) × (R 5 / R 3 ) × Eo + (1 + R 5 /
R 4 ) × Eo
【0004】第1、第2感温抵抗素子は略同一温度で少
なくとも100℃以上に加熱されるように構成された感
温抵抗素子を利用した湿度検出回路においては、感温抵
抗素子は、通常、少なくとも水の沸点温度以上に自己加
熱させられている。このような温度で自己加熱している
第1感温抵抗素子は雰囲気温度の変化による抵抗値変化
の外にその時の絶体湿度量に応じた抵抗値変化を示す。
すなわち湿度量が多いと自己加熱温度が湿度により冷却
され雰囲気温度より低くなる。従って上記の式でも示さ
れるように第1の感温抵抗素子と第2の感温抵抗素子の
抵抗比を電圧変換することで雰囲気温度を補正しつつ絶
対湿度量を検出する方式が知られている。In a humidity detecting circuit using a temperature-sensitive resistance element configured so that the first and second temperature-sensitive resistance elements are heated to at least 100 ° C. at substantially the same temperature, the temperature-sensitive resistance element is usually , At least to the boiling point of water. The first temperature-sensitive resistance element that is self-heated at such a temperature exhibits a resistance value change according to the absolute humidity at that time, in addition to a resistance value change due to a change in ambient temperature.
That is, when the humidity is large, the self-heating temperature is cooled by the humidity and becomes lower than the ambient temperature. Therefore, a method of detecting the absolute humidity while correcting the ambient temperature by converting the resistance ratio of the first temperature-sensitive resistance element to the resistance value of the second temperature-sensitive resistance element as shown in the above equation is known. I have.
【0005】[0005]
【発明が解決しようとする課題】しかしながら、上記の
ように構成された従来の湿度検出回路では、絶対湿度量
を検出できても温度変化を検出することはできなかっ
た。従って、温度測定が必要な場合は新たな温度測定装
置を設ける必要であった。However, in the conventional humidity detecting circuit constructed as described above, a change in temperature cannot be detected even if the absolute humidity amount can be detected. Therefore, when temperature measurement is required, it is necessary to provide a new temperature measuring device.
【0006】[0006]
【課題を解決するための手段】本発明には以下に示す3
種類の発明がある。第1の発明は、第1および第2感温
抵抗素子を具備し、第1感温抵抗素子を雰囲気に暴露す
ると共に、第2感温抵抗素子を密閉状態にし、第1、第
2感温抵抗素子を略同一温度で少なくとも100℃以上
に加熱される雰囲気中に置き、その雰囲気による第1、
第2感温抵抗素子の抵抗値変化を電圧変換して温湿度変
化を検出するように構成した温湿度検出回路であって、
第1と第2の感温抵抗素子を直列に接続し、さらに第1
感温抵抗素子に直列に接続した抵抗体と、第2感温抵抗
素子を定電圧駆動するとともに定電圧駆動された第2感
温抵抗素子に流れる同じ電流値で第1感温抵抗素子およ
び抵抗体を駆動する定電圧駆動回路とを備え、前記抵抗
体の両端電圧を検出し温度出力とすることを特徴とする
温湿度検出回路を提供するものである。Means for Solving the Problems The present invention provides the following 3
There are different kinds of inventions. A first invention includes first and second temperature-sensitive resistance elements, exposing the first temperature-sensitive resistance element to an atmosphere, and closing the second temperature-sensitive resistance element to form a first and second temperature-sensitive resistance element. The resistance element is placed in an atmosphere heated to at least 100 ° C. or more at substantially the same temperature, and the first,
A temperature / humidity detection circuit configured to detect a temperature / humidity change by converting a resistance value change of a second temperature-sensitive resistance element into a voltage,
First and second temperature-sensitive resistance elements are connected in series, and
A resistor connected in series with the temperature sensitive resistive element, a first temperature sensitive resistor element and the resistor with the same current flowing through the second temperature sensitive resistor element to a second temperature sensitive resistor element constant voltage drive with a constant voltage drive and a constant voltage drive circuit for driving the body, there is provided a temperature and humidity detecting circuit, characterized in that the detected temperature output voltage across the resistor.
【0007】第2の発明は、第1および第2感温抵抗素
子を具備し、第1感温抵抗素子を雰囲気に暴露すると共
に、第2感温抵抗素子を密閉状態にし、第1、第2感温
抵抗素子を略同一温度で少なくとも100℃以上に加熱
される雰囲気中に置き、その雰囲気による第1、第2感
温抵抗素子の抵抗値変化を電圧変換して温湿度変化を検
出するように構成した温湿度検出回路であって、第1と
第2の感温抵抗素子を直列に接続し、さらに第2感温抵
抗素子に直列に接続した電流設定用の抵抗体と、この抵
抗体に並列に接続したスイッチング素子と、第2感温抵
抗素子および抵抗体を定電圧駆動するとともに定電圧駆
動された第2感温抵抗素子および抵抗体に流れる同じ電
流値で第1感温抵抗素子を駆動する定電圧駆動回路とを
備え、湿度検出時には前記スイッチング素子をオンと
し、温度検出時には前記スイッチング素子をオフとして
切り替えることを特徴とする温湿度検出回路を提供する
ものである。According to a second aspect of the present invention, the first and second temperature-sensitive resistance elements are provided, and the first and second temperature-sensitive resistance elements are exposed to an atmosphere, and the second temperature-sensitive resistance element is sealed. The two temperature-sensitive resistance elements are placed in an atmosphere heated to at least 100 ° C. or more at substantially the same temperature, and a change in the resistance value of the first and second temperature-sensitive resistance elements due to the atmosphere is converted into a voltage to detect a change in temperature and humidity. A temperature-humidity detecting circuit configured as described above, wherein a first and second temperature-sensitive resistance elements are connected in series, and a current setting resistor connected in series to the second temperature-sensitive resistance element; a switching element connected in parallel to the body, a first temperature sensitive resistor with the same current flowing through the second temperature sensitive resistor element and the resistor to the second temperature sensitive resistor element and the resistor is constant voltage drive with a constant voltage drive and a constant voltage drive circuit for driving the device, when the humidity detected And ON the switching element
And, at the time of temperature detection is to provide a temperature and humidity detecting circuits and switches <br/> the switching element as an off.
【0008】第3の発明は、第1および第2感温抵抗素
子を具備し、第1感温抵抗素子を雰囲気に暴露すると共
に、第2感温抵抗素子を密閉状態にし、第1、第2感温
抵抗素子を略同一温度で少なくとも100℃以上に加熱
される雰囲気中に置き、その雰囲気による第1、第2感
温抵抗素子の抵抗値変化を電圧変換して温湿度変化を検
出するように構成した温湿度検出回路であって、第1感
温抵抗素子に第2感温抵抗素子を直列に接続し、さらに
第2感温抵抗素子に並列に接続した電流設定用の抵抗体
と、第2感温抵抗素子または抵抗体を定電圧駆動すると
ともに第2感温抵抗素子または抵抗体に流れる同じ電流
値で第1感温抵抗素子を駆動する定電圧駆動回路と、第
2感温抵抗素子か抵抗体を定電圧駆動するかを切り替え
るスイッチング素子とを備え、前記スイッチング素子に
より、湿度検出時には前記第2感温抵抗体素子を定電圧
駆動し、温度検出時には前記抵抗体を定電圧駆動するよ
うに切り替えることを特徴とする温湿度検出回路を提供
するものである。According to a third aspect of the present invention, there are provided first and second temperature-sensitive resistance elements. The first and second temperature-sensitive resistance elements are exposed to an atmosphere, and the second temperature-sensitive resistance element is sealed. The two temperature-sensitive resistance elements are placed in an atmosphere heated to at least 100 ° C. or more at substantially the same temperature, and a change in the resistance value of the first and second temperature-sensitive resistance elements due to the atmosphere is converted into a voltage to detect a change in temperature and humidity. A temperature-humidity detecting circuit configured as described above, wherein a second temperature-sensitive resistor is connected in series to the first temperature-sensitive resistor, and a current setting resistor connected in parallel to the second temperature-sensitive resistor.
When the second temperature-sensitive resistor or resistor is driven at a constant voltage ,
The same current both flowing through the second temperature-sensitive resistance element or resistor
Includes a constant voltage drive circuit for driving the first temperature sensitive resistor element with a value, and switching elements of the second temperature sensitive resistance element or resistor switching between the constant voltage driving, by the switching element, wherein at the time of the humidity detecting the (2) The temperature- sensitive resistor element is driven at a constant voltage, and when the temperature is detected, the resistor is driven at a constant voltage.
The temperature and humidity detection circuit is characterized in that switching is performed in the following manner.
【0009】前記スイッチング素子により温度出力に切
り替える際に、電流設定用の抵抗体の抵抗値は、第1感
温抵抗素子が湿度に対しては抵抗値変化を示すことが無
い自己加熱温度以下になる通電電流値に設定するように
構成されることが好ましい。When switching to the temperature output by the switching element, the resistance value of the current setting resistor is set to be equal to or lower than the self-heating temperature at which the first temperature-sensitive resistance element does not show a change in resistance value against humidity. It is preferable that the configuration is such that the current value is set as follows.
【0010】[0010]
【作用】第1の発明によれば、第2感温抵抗素子の抵抗
値は雰囲気温度で決定されるが通電電流値は第2感温抵
抗素子の抵抗値と印加電圧で決定されるため、この通電
電流値を第1感温抵抗素子に接続された抵抗体で検出す
ることで温度出力を得ることができる。According to the first aspect of the invention, the resistance value of the second temperature-sensitive resistor is determined by the ambient temperature, but the current value is determined by the resistance value of the second temperature-sensitive resistor and the applied voltage. A temperature output can be obtained by detecting this energizing current value with a resistor connected to the first temperature-sensitive resistance element.
【0011】第2の発明によれば、温度検出時は、第
1、第2感温抵抗素子の通電電流値が小さく設定される
ので、自己加熱温度が下がり、第1感温抵抗素子は湿度
の影響による抵抗値変化を示さなくなる。よって、出力
電圧は第1感温抵抗素子の抵抗値と第2感温抵抗素子の
抵抗値と直列に接続された抵抗値との合算値との比を示
すこととなり、温度変化による抵抗比の変化を電圧変換
により温度出力を得ることができる。According to the second aspect of the present invention, when the temperature is detected, the current values of the first and second temperature-sensitive resistance elements are set to be small. No change in resistance value due to the influence of. Therefore, the output voltage indicates the ratio of the resistance value of the first temperature-sensitive resistance element to the sum of the resistance value of the second temperature-sensitive resistance element and the resistance value connected in series. The temperature output can be obtained by converting the change into a voltage.
【0012】第3の発明によれば、温度検出時は、第1
感温抵抗素子の通電電流値が小さく設定されるので、自
己加熱温度が下がり、第1感温抵抗素子は湿度の影響に
よる抵抗値変化を示さなくなる。よって、出力電圧は第
1感温抵抗素子の抵抗値と、抵抗体の抵抗値との比を示
すこととなり、温度変化による抵抗比の変化を電圧変換
により温度出力を得ることができる。According to the third aspect, when the temperature is detected, the first
Since the current value of the temperature-sensitive resistance element is set to be small, the self-heating temperature decreases, and the first temperature-sensitive resistance element does not show a resistance value change due to the influence of humidity. Therefore, the output voltage indicates the ratio of the resistance value of the first temperature-sensitive resistance element to the resistance value of the resistor, and a temperature output can be obtained by converting the change in the resistance ratio due to the temperature change into a voltage.
【0013】[0013]
【実施例】以下、図面に示す3種類の実施例を用いて本
発明を詳述する。なお、これによって本発明が限定され
るものでない。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to three embodiments shown in the drawings. Note that the present invention is not limited by this.
【0014】図1は本発明による実施例1の温湿度検出
回路である。図1において、Rsは湿気を含む雰囲気に
暴露され湿度変化を検出する第1感温抵抗素子、Rrは
その雰囲気の温度変化を検出する第2感温抵抗素子、A
1はオペアンプ、R1、R2 R6は固定抵抗、Evはこの温
湿度検出回路に供給される直流定電圧である。また、E
oはR1とR2で決定される基準電圧でありオペアンプA1
で定電圧駆動回路を構成している。FIG. 1 shows a temperature and humidity detecting circuit according to a first embodiment of the present invention. In FIG. 1, Rs is a first resistance element for detecting a change in humidity when exposed to an atmosphere containing moisture, Rr is a second resistance element for detecting a change in temperature of the atmosphere, A
1 is an operational amplifier, R 1 , R 2 and R 6 are fixed resistors, and Ev is a DC constant voltage supplied to the temperature / humidity detecting circuit. Also, E
o is a reference voltage determined by R 1 and R 2 , and the operational amplifier A 1
Constitute a constant voltage drive circuit.
【0015】Io(=Eo/Rr)は固定抵抗R6 、第1感
温抵抗素子Rs 、第2感温抵抗素子Rrに流れる電流値
である。この時の湿度検知出力VAHは次式で示される。 VAH=V1=(1+Rs/Rr)×Eo また、この時の温度検知出力VTは次式で示され、固定
抵抗(R6)の両端電圧VTを検知している。 VT=V2−V1={1+( Rs +R6)/ Rr }×Eo −
( 1+Rs/Rr)×Eo=(R6/Rr)×Eo 即ち、湿度検知出力はRs/Rrの比を、温度検知出力は
R6/Rrの比をそれぞれ電圧変換していることになる。Io (= Eo / Rr) is a current value flowing through the fixed resistor R 6 , the first temperature-sensitive resistor Rs, and the second temperature-sensitive resistor Rr. The humidity detection output V AH at this time is expressed by the following equation. V AH = V 1 = (1 + Rs / Rr) × Eo The temperature detection output V T at this time is represented by the following formula, which detects a fixed voltage across V T of the resistor (R 6). V T = V 2 -V 1 = {1+ (Rs + R 6) / Rr} × Eo -
(1 + Rs / Rr) × Eo = (R 6 / Rr) × Eo i.e., humidity detection output ratio of Rs / Rr, so that the temperature detection output are respectively voltage conversion ratio of R 6 / Rr.
【0016】図2は第1、第2感温抵抗素子に用いられ
る白金抵抗の温度−抵抗値特性を示す説明図である。図
2に示すように、白金抵抗は正の温度係数を持つために
図2に示すような特性を示す。FIG. 2 is an explanatory diagram showing temperature-resistance characteristics of platinum resistors used in the first and second temperature-sensitive resistance elements. As shown in FIG. 2, the platinum resistor has a positive temperature coefficient and thus exhibits the characteristics shown in FIG.
【0017】以下、図1に基づいて検出原理を説明す
る。通常湿度検知時は200〜400°C程度に自己加
熱するように電流値は設定される。即ちRrの両端電圧
は上記温度に設定されるような抵抗値になるようにIo
=Eo/Rrで設定される電流値で駆動される。この場合
でも第1、第2の感温抵抗素子は雰囲気の温度変化に対
して抵抗値を同一の変化率で変化させる。Hereinafter, the principle of detection will be described with reference to FIG. At the time of normal humidity detection, the current value is set so as to self-heat to about 200 to 400 ° C. That is, Io is set so that the voltage across Rr becomes a resistance value set at the above temperature.
= Eo / Rr. Even in this case, the first and second temperature-sensitive resistance elements change their resistance values at the same rate of change with respect to the temperature change of the atmosphere.
【0018】一方湿度変化が生じると湿度の状態に応じ
て第1感温抵抗素子のみが抵抗値を変化させるためにR
s/Rrの比に変化が生じ湿度に応じた出力変化が発生す
る。一方当該回路における通電電流値はEo/Rrで決定
される。即ち温度が変化したとき第2の感温抵抗素子の
抵抗値はその変化に応じて変動するがそれに従い通電電
流値も変化する。従って、その通電電流値の変化を抵抗
R6の両端電圧の変化として検出すれば温度検出ができ
る。On the other hand, when a change in humidity occurs, only the first temperature-sensitive resistance element changes the resistance value according to the state of humidity.
The ratio of s / Rr changes, and the output changes according to the humidity. On the other hand, the current value in the circuit is determined by Eo / Rr. That is, when the temperature changes, the resistance value of the second temperature-sensitive resistance element changes according to the change, and the current value changes accordingly. Therefore, the temperature can be detected by detecting the change in the electric current value as a change in voltage across the resistor R 6.
【0019】図3は本発明による実施例2の温湿度検出
回路である。図3において、Rsは湿気を含む雰囲気に
暴露され湿度変化を検出する第1感温抵抗素子、Rrは
その雰囲気の温度変化を検出する第2感温抵抗素子、A
1、A2はオペアンプ、R1〜R3、R40、R41、R60は固
定抵抗、S1、S2はスイッチ(スイッチング素子)であ
る。Evはこの温湿度検出回路に供給される直流定電圧
である。また、EoはR1とR2で決定される基準電圧で
ありオペアンプA1で定電圧・定電流回路を構成してい
る。また、Io(=Eo/(Rr +R60) )は第1感温抵
抗素子Rs 、第2感温抵抗素子Rr 、固定抵抗R60(電
流設定用の抵抗)に流れる電流値である。なお、Rs 、
Rr には正の温度係数の白金抵抗が用いられる。FIG. 3 shows a temperature and humidity detecting circuit according to a second embodiment of the present invention. In FIG. 3, Rs is a first temperature-sensitive resistance element that detects a change in humidity when exposed to an atmosphere containing moisture, Rr is a second temperature-sensitive resistance element that detects a temperature change in the atmosphere, A
1 and A 2 are operational amplifiers, R 1 to R 3 , R 40 , R 41 and R 60 are fixed resistors, and S 1 and S 2 are switches (switching elements). Ev is a DC constant voltage supplied to the temperature and humidity detection circuit. Further, Eo constitute a constant voltage and constant current circuit in the operational amplifier A 1 is a reference voltage determined by R 1 and R 2. Furthermore, Io (= Eo / (Rr + R 60)) is a current value flowing first temperature sensitive resistor element Rs, second temperature sensitive resistor element Rr, the fixed resistor R 60 (resistance of the current setting). Note that Rs,
A platinum resistance having a positive temperature coefficient is used for Rr.
【0020】図3の(1)はスイッチS1、S2がオンさ
れた湿度検出時の状態を示す。従って、この時の湿度検
知出力VAHは次式で示される。 VAH=Vout =−(Rs/Rr)×(R5/R3)×Eo +(1+
R5/Z4)×Eo 但し Z4 =R40×R41/(R40+R41) 図3の(2)はスイッチS1、S2がオフされた温度検知
時の状態を示す。従って、この時の温度検知出力VTは次
式で示される。 VT =Vout =−{Rs/( Rr +R60)}×(R5/R3)×
Eo+(1+R5/R4)×EoFIG. 3A shows a state when the switches S 1 and S 2 are turned on and humidity is detected. Therefore, the humidity detection output V AH at this time is expressed by the following equation. V AH = Vout = - (Rs / Rr) × (R 5 / R 3) × Eo + (1+
R 5 / Z 4 ) × Eo where Z 4 = R 40 × R 41 / (R 40 + R 41 ) FIG. 3B shows the state at the time of temperature detection when the switches S 1 and S 2 are turned off. Accordingly, the temperature detection output V T at this time is represented by the following formula. V T = Vout = - {Rs / (Rr + R 60)} × (R 5 / R 3) ×
Eo + (1 + R 5 / R 4 ) × Eo
【0021】即ち、湿度検知時はRs/Rrの比を、温度
検知時はRs/(Rr +R60)の比をそれぞれ電圧変換して
いることになる。尚、Z4の値は湿度検知時、温度検知
時それぞれの比に応じたR3/Z4になるようにR41の切
り替えで設定される。That is, when humidity is detected, the ratio of Rs / Rr is converted, and when temperature is detected, the ratio of Rs / (Rr + R 60 ) is converted. The value of Z 4 when the humidity detecting, set by switching of the R 41 to be R 3 / Z 4 in accordance with the respective ratios during temperature detection.
【0022】図4は第1、第2感温抵抗素子に用いられ
る白金抵抗の電流−電圧特性を示す説明図である。白金
抵抗は正の温度係数を持つために図4に示すような特性
を示す。FIG. 4 is an explanatory diagram showing current-voltage characteristics of platinum resistors used for the first and second temperature-sensitive resistance elements. Since the platinum resistance has a positive temperature coefficient, it exhibits characteristics as shown in FIG.
【0023】以下、図3に基づいて検出原理を説明す
る。即ち印加電流(電圧)が小さいと抵抗値は小さく自
己加熱温度も低い。一方印加電流(電圧)が大きいと抵
抗値は大きく自己加熱温度が高くなる。通常湿度検知時
は200〜400°C程度に自己加熱するように電流値
は設定される。即ち、Rrの両端電圧は上記温度に設定
されるような抵抗値になるようにIo=Eo/Rrで設定さ
れる電流値で駆動される。Hereinafter, the principle of detection will be described with reference to FIG. That is, when the applied current (voltage) is small, the resistance value is small and the self-heating temperature is low. On the other hand, when the applied current (voltage) is large, the resistance value is large and the self-heating temperature is high. At the time of normal humidity detection, the current value is set so as to self-heat to about 200 to 400 ° C. That is, the voltage across Rr is driven with a current value set by Io = Eo / Rr such that the resistance value is set to the above-mentioned temperature.
【0024】この場合でも第1、第2の感温抵抗素子は
雰囲気の温度変化に対して抵抗値を同一感温抵抗素子の
みが抵抗値を変化させるためRs/Rrの比に変化が生じ
湿度に応じた出力変化が発生する。一方温度検出時は同
様のEoに対して第2の感温抵抗素子に直列に接続され
たR 60 の合成抵抗値で設定される電流値Io=Eo/(Rr
+R60)で駆動されることになる。Even in this case, the first and second temperature-sensitive resistance elements have the same resistance value with respect to a change in ambient temperature, and only the same temperature-sensitive resistance element changes the resistance value. An output change occurs according to. On the other hand the current value Io at the temperature detection is set by the combined resistance value of R 60 which are connected in series to the second thermo-sensitive resistance elements for similar Eo = Eo / (Rr
+ R 60 ).
【0025】この時R60の値は感温抵抗体が湿度に対し
ては抵抗値変化を生じない自己加熱温度になる電流値に
なるように設定される。この場合でも第1、第2の感温
抵抗素子は温度変化に対して同様の変化率を示すが、第
2の感温抵抗素子にはR60が直列に接続されるためにR
s/(Rr+R60)の比は温度によって異なることなり、従
って温度変化により出力が変化するので、この出力変化
より温度検知が可能となる。The value of this time R 60 is set to be the current value becomes self-heating temperature thermo-sensitive resistor does not produce a change in resistance against humidity. First In this case, the second temperature sensitive resistor element exhibits a similar change rate with respect to temperature changes, the second temperature sensitive resistor element R to R 60 are connected in series
Since the ratio of s / (Rr + R 60 ) varies depending on the temperature, and the output changes according to the temperature change, the temperature can be detected from the output change.
【0026】図5は本発明による実施例3の温湿度検出
回路である。図5において、Rsは湿気を含む雰囲気に
暴露され湿度変化を検出する第1感温抵抗素子、Rrは
その雰囲気の温度変化を検出する第2感温抵抗素子、A
1、A2はオペアンプ、R1〜R3、R40、R41、R60は固
定抵抗、S2、S3はスイッチ(スイッチング素子)であ
る。Evはこの温湿度検出回路に供給される直流定電圧
である。また、EoはR 1とR2で決定される基準電圧で
ありオペアンプA1で定電圧・定電流回路を構成してい
る。また、Io(=Eo/(Rr+R60))は第1感温抵抗素
子Rs、第2感温抵抗素子Rr、固定抵抗R60に流れる電
流値である。なお、Rs、Rrはの正の温度係数の白金抵
抗が用いられる。FIG. 5 shows temperature and humidity detection according to a third embodiment of the present invention.
Circuit. In FIG. 5, Rs is an atmosphere containing moisture.
The first temperature-sensitive resistance element that detects the change in humidity due to exposure, Rr
A second temperature-sensitive resistance element for detecting a temperature change of the atmosphere, A
1, ATwoIs an operational amplifier, R1~ RThree, R40, R41, R60Is solid
Constant resistance, STwo, SThreeIs a switch (switching element)
You. Ev is the DC constant voltage supplied to this temperature and humidity detection circuit.
It is. Eo is R 1And RTwoWith the reference voltage determined by
Operational amplifier A1Constitute a constant voltage / constant current circuit.
You. Also, Io (= Eo / (Rr + R60)) Is the first temperature-sensitive resistor
Child Rs, second temperature-sensitive resistance element Rr, fixed resistance R60Electricity flowing through
It is a streaming value. Note that Rs and Rr are platinum resistors having a positive temperature coefficient.
Anti is used.
【0027】図5の(1)はスイッチS2がオン、スイ
ッチS3が第2感温度抵抗素子を通電した湿度検出時の
状態を示す。従って、この時の湿度検知出力VAHは次式
で示される。 VAH=Vout =−(Rs/Rr)×(R5/R3)×Eo+(1+R
5/Z4)×Eo 但し Z4=R40×R41/(R40+R41) 図5の(2)はスイッチS2がオフ、スイッチS3が固定
抵抗R61を通電した温度検知時の状態を示す。 従って、
この時の温度検知出力VTは次式で示される。 VT =Vout =−(Rs/R61)×(R5/R3)×Eo+(1+
R5/R4)×EoFIG. 5A shows the state when the switch S 2 is turned on and the switch S 3 detects the humidity when the second temperature-sensitive resistance element is energized. Therefore, the humidity detection output V AH at this time is expressed by the following equation. V AH = Vout = - (Rs / Rr) × (R 5 / R 3) × Eo + (1 + R
5 / Z 4 ) × Eo where Z 4 = R 40 × R 41 / (R 40 + R 41 ) FIG. 5 (2) shows the temperature detection when the switch S 2 is off and the switch S 3 is energized through the fixed resistor R 61. The state of is shown. Therefore,
Temperature detection output V T at this time is represented by the following formula. V T = Vout = − (Rs / R 61 ) × (R 5 / R 3 ) × Eo + (1+
R 5 / R 4 ) × Eo
【0028】即ち印加電流(電圧)が小さいと抵抗値は
小さく自己加熱温度も低い。一方印加電流(電圧)が大
きいと抵抗値は大きく自己加熱温度が高くなる。通常湿
度検知時は200〜400℃程度に自己加熱するように
電流値は設定される。即ちRrの両端電圧は上記温度に
設定されるような抵抗値になるようにIo=Eo/Rrで設
定される電流値で駆動される。That is, when the applied current (voltage) is small, the resistance value is small and the self-heating temperature is low. On the other hand, when the applied current (voltage) is large, the resistance value is large and the self-heating temperature is high. At the time of normal humidity detection, the current value is set so as to self-heat to about 200 to 400 ° C. That is, the voltage across Rr is driven by a current value set by Io = Eo / Rr so that the resistance value is set to the above-mentioned temperature.
【0029】この場合でも第1、第2の感温抵抗素子は
雰囲気の温度変化に対して抵抗値を同一の変化率で変化
させる。一方湿度変化が生じると湿度の状態に応じて第
1感温抵抗体のみが抵抗値を変化させるためにRs/Rr
の比に変化が生じ湿度に応じた出力変化が発生する。一
方温度検出時は同様のEoに対して固定抵抗R 61 で設定
される電流値Eo/R 61 で駆動されることになる。Even in this case, the resistance values of the first and second temperature-sensitive resistance elements change at the same rate of change with respect to the temperature change of the atmosphere. On the other hand, when the humidity changes, only the first temperature-sensitive resistor changes the resistance value according to the humidity state, so that Rs / Rr
And the output changes according to the humidity. While the temperature detection time will be driven at a current value Eo / R 61 that is set by the fixed resistor R 61 for similar Eo.
【0030】この時R 61 の値は感温抵抗体が湿度に対し
ては抵抗値変化を生じない自己加熱温度になる電流値に
なるように設定される。この場合でも第1感温抵抗素子
は温度変化に対して同様の変化率を示すが、電流設定用
の固定抵抗R 61 は固定値のためRs/R 61 の比は温度によ
って異なることになり温度変化により出力が変化するこ
とになり、この出力変化より温度検知が可能となる。The value of this time R 61 is set to be the current value becomes self-heating temperature thermo-sensitive resistor does not produce a change in resistance against humidity. The first temperature sensitive resistor element even when the shows a similar change rate with respect to temperature changes, the fixed resistor R 61 for current setting ratio Rs / R 61 for a fixed value will be depend on the temperature the temperature The output changes due to the change, and the temperature can be detected from the output change.
【0031】[0031]
【発明の効果】本発明によれば温度検知用の専用の装置
を用いることなく温湿度の検出が可能になる。According to the present invention, temperature and humidity can be detected without using a dedicated device for detecting temperature.
【図1】本発明による実施例1の温湿度検出回路であ
る。FIG. 1 is a temperature and humidity detection circuit according to a first embodiment of the present invention.
【図2】第1、第2感温抵抗素子に用いられる白金抵抗
の温度−抵抗値特性を示す説明図である。FIG. 2 is an explanatory diagram showing temperature-resistance characteristics of platinum resistors used for first and second temperature-sensitive resistance elements.
【図3】本発明による実施例2の温湿度検出回路であ
る。FIG. 3 is a temperature and humidity detection circuit according to a second embodiment of the present invention.
【図4】第1、第2感温抵抗素子に用いられる白金抵抗
の電流−電圧特性を示す説明図である。FIG. 4 is an explanatory diagram showing current-voltage characteristics of platinum resistors used for first and second temperature-sensitive resistance elements.
【図5】本発明による実施例3の温湿度検出回路であ
る。FIG. 5 is a temperature and humidity detection circuit according to a third embodiment of the present invention.
【図6】従来例1の湿度検出回路である。FIG. 6 is a humidity detection circuit of Conventional Example 1.
【図7】従来例2の湿度検出回路である。FIG. 7 is a humidity detection circuit of Conventional Example 2.
R1 固定抵抗 R2 固定抵抗 R3 固定抵抗 R4 固定抵抗 R5 固定抵抗 R6 固定抵抗 R40 固定抵抗 R41 固定抵抗 R60 固定抵抗 R61 固定抵抗 Rs 感温抵抗素子 Rr 感温抵抗素子 A1 オペアンプ A2 オペアンプ S1 スイッチ S2 スイッチ S3 スイッチR 1 fixed resistor R 2 fixed resistor R 3 fixed resistor R 4 fixed resistor R 5 fixed resistor R 6 fixed resistor R 40 fixed resistor R 41 fixed resistor R 60 fixed resistor R 61 fixed resistor Rs temperature sensitive resistive element Rr temperature sensitive resistive element A 1 operational amplifier A 2 op-amp S 1 switch S 2 switch S 3 switch
Claims (4)
第1感温抵抗素子を雰囲気に暴露すると共に、第2感温
抵抗素子を密閉状態にし、第1、第2感温抵抗素子を略
同一温度で少なくとも100℃以上に加熱される雰囲気
中に置き、その雰囲気による第1、第2感温抵抗素子の
抵抗値変化を電圧変換して温湿度変化を検出するように
構成した温湿度検出回路であって、第1と第2の感温抵
抗素子を直列に接続し、さらに第1感温抵抗素子に直列
に接続した抵抗体と、第2感温抵抗素子を定電圧駆動す
るとともに定電圧駆動された第2感温抵抗素子に流れる
同じ電流値で第1感温抵抗素子および抵抗体を駆動する
定電圧駆動回路とを備え、前記抵抗体の両端電圧を検出
し温度出力とすることを特徴とする温湿度検出回路。And a first temperature-sensitive resistance element.
The first temperature-sensitive resistor is exposed to the atmosphere, the second temperature-sensitive resistor is sealed, and the first and second temperature-sensitive resistors are placed in an atmosphere heated to at least 100 ° C. at substantially the same temperature. A temperature-humidity detecting circuit configured to detect a temperature-humidity change by converting a resistance value change of the first and second temperature-sensitive resistance elements due to the atmosphere into a voltage, and comprising a first and a second temperature-sensitive resistance element. were connected in series, further a resistor connected in series to the first temperature sensitive resistor element, constant voltage driven the same current flowing through the second temperature sensitive resistive element with a second temperature sensitive resistive element to a constant voltage drive in a constant-voltage drive circuit for driving the first temperature sensitive resistor element and the resistor, the temperature and humidity detecting circuit, characterized in that the detected temperature output voltage across the resistor.
第1感温抵抗素子を雰囲気に暴露すると共に、第2感温
抵抗素子を密閉状態にし、第1、第2感温抵抗素子を略
同一温度で少なくとも100℃以上に加熱される雰囲気
中に置き、その雰囲気による第1、第2感温抵抗素子の
抵抗値変化を電圧変換して温湿度変化を検出するように
構成した温湿度検出回路であって、第1と第2の感温抵
抗素子を直列に接続し、さらに第2感温抵抗素子に直列
に接続した電流設定用の抵抗体と、この抵抗体に並列に
接続したスイッチング素子と、第2感温抵抗素子および
抵抗体を定電圧駆動するとともに定電圧駆動された第2
感温抵抗素子および抵抗体に流れる同じ電流値で第1感
温抵抗素子を駆動する定電圧駆動回路とを備え、湿度検
出時には前記スイッチング素子をオンとし、温度検出時
には前記スイッチング素子をオフとして切り替えること
を特徴とする温湿度検出回路。2. It comprises first and second temperature-sensitive resistance elements,
The first temperature-sensitive resistor is exposed to the atmosphere, the second temperature-sensitive resistor is sealed, and the first and second temperature-sensitive resistors are placed in an atmosphere heated to at least 100 ° C. at substantially the same temperature. A temperature-humidity detecting circuit configured to detect a temperature-humidity change by converting a resistance value change of the first and second temperature-sensitive resistance elements due to the atmosphere into a voltage, and comprising a first and a second temperature-sensitive resistance element. Are connected in series, and furthermore, a current setting resistor connected in series to the second temperature-sensitive resistor, a switching element connected in parallel to this resistor, and a constant voltage connected to the second temperature-sensitive resistor and the resistor. Driven and constant voltage driven second
And a constant voltage drive circuit for driving the first temperature sensitive resistor element at the same current value flowing through the temperature sensing resistor element and the resistor, humidity test
When the temperature is detected, the switching element is turned on.
Temperature and humidity detecting circuit, characterized in that switching the switching element as an off to.
第1感温抵抗素子を雰囲気に暴露すると共に、第2感温
抵抗素子を密閉状態にし、第1、第2感温抵抗素子を略
同一温度で少なくとも100℃以上に加熱される雰囲気
中に置き、その雰囲気による第1、第2感温抵抗素子の
抵抗値変化を電圧変換して温湿度変化を検出するように
構成した温湿度検出回路であって、第1感温抵抗素子に
第2感温抵抗素子を直列に接続し、さらに第2感温抵抗
素子に並列に接続した電流設定用の抵抗体と、第2感温
抵抗素子または抵抗体を定電圧駆動するとともに第2感
温抵抗素子または抵抗体に流れる同じ電流値で第1感温
抵抗素子を駆動する定電圧駆動回路と、第2感温抵抗素
子か抵抗体を定電圧駆動するかを切り替えるスイッチン
グ素子とを備え、前記スイッチング素子により、湿度検
出時には前記第2感温抵抗体素子を定電圧駆動し、温度
検出時には前記抵抗体を定電圧駆動するように切り替え
ることを特徴とする温湿度検出回路。3. It comprises first and second temperature-sensitive resistance elements,
The first temperature-sensitive resistor is exposed to the atmosphere, the second temperature-sensitive resistor is sealed, and the first and second temperature-sensitive resistors are placed in an atmosphere heated to at least 100 ° C. at substantially the same temperature. A temperature / humidity detecting circuit configured to detect a temperature / humidity change by converting a resistance value change of the first and second temperature-sensitive resistance elements due to the atmosphere into a voltage. the temperature resistance element connected in series, further a resistor for current setting is connected in parallel to a second temperature sensitive resistor element, the second sense with the second temperature sensitive resistive element or resistor to a constant voltage drive
The first temperature sensing with the same current value flowing through the temperature resistance element or resistor
It includes a constant voltage drive circuit for driving the resistive element, and switching elements of the second temperature sensitive resistance element or resistor switching between the constant voltage driving, by the switching element, the humidity test
At the time of output, the second temperature-sensitive resistor element is driven at a constant voltage ,
A temperature / humidity detection circuit that switches the resistor so as to be driven at a constant voltage upon detection.
切り替える際に、電流設定用の抵抗体の抵抗値は、第一
感温抵抗素子が湿度に対しては抵抗値変化を示すことが
無い自己加熱温度以下になる通電電流値に設定すること
を特徴とした請求項3記載の温湿度検出回路。4. When the switching element switches to temperature output, the resistance value of the current setting resistor is set to a self-heating temperature at which the first temperature-sensitive resistance element does not show a resistance value change with respect to humidity. 4. The temperature / humidity detecting circuit according to claim 3, wherein the current value is set to the following value.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP22888792A JP2885581B2 (en) | 1992-08-27 | 1992-08-27 | Temperature and humidity detection circuit |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP22888792A JP2885581B2 (en) | 1992-08-27 | 1992-08-27 | Temperature and humidity detection circuit |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0674929A JPH0674929A (en) | 1994-03-18 |
JP2885581B2 true JP2885581B2 (en) | 1999-04-26 |
Family
ID=16883418
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JP22888792A Expired - Fee Related JP2885581B2 (en) | 1992-08-27 | 1992-08-27 | Temperature and humidity detection circuit |
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JP (1) | JP2885581B2 (en) |
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JP2010256172A (en) * | 2009-04-24 | 2010-11-11 | Yazaki Corp | Gas detector and method of correcting temperature of the same |
CN114977504B (en) * | 2022-06-02 | 2023-10-24 | 国网山东省电力公司泰安供电公司 | Bypass load switch control system |
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1992
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