JPS638422B2 - - Google Patents
Info
- Publication number
- JPS638422B2 JPS638422B2 JP54009517A JP951779A JPS638422B2 JP S638422 B2 JPS638422 B2 JP S638422B2 JP 54009517 A JP54009517 A JP 54009517A JP 951779 A JP951779 A JP 951779A JP S638422 B2 JPS638422 B2 JP S638422B2
- Authority
- JP
- Japan
- Prior art keywords
- humidity
- voltage
- humidity sensor
- pulse
- changes
- 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
- 238000005259 measurement Methods 0.000 claims description 5
- 230000010355 oscillation Effects 0.000 claims description 4
- 238000010586 diagram Methods 0.000 description 4
- 230000006866 deterioration Effects 0.000 description 3
- 238000005868 electrolysis reaction Methods 0.000 description 2
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
Landscapes
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Description
【発明の詳細な説明】
本発明は相対湿度の測定が、高精度、長寿命で
行なえるようにした湿度測定回路に関するもので
ある。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a humidity measuring circuit that can measure relative humidity with high accuracy and long life.
従来より、相対湿度を測定するために湿度セン
サに交流信号を印加し、その出力端に相対湿度に
応じた電圧を得るようにしたものが知られている
が、この種の測定回路においては、交流電圧の安
定化が困難で精度も高くとれないという問題があ
る。 Conventionally, in order to measure relative humidity, it has been known to apply an AC signal to a humidity sensor and obtain a voltage corresponding to the relative humidity at its output terminal.In this type of measurement circuit, There are problems in that it is difficult to stabilize the AC voltage and high accuracy cannot be achieved.
そこで、第１図に示すようにパルス発生器１か
らの第２図に示すようなパルス電圧を、
MgCr2O4とTiO2とからなる多孔質焼結体で構成
した湿度センサー２に印加し、出力端子３から相
対湿度に応じた電圧をとり出すようにした測定回
路が使用されている。 Therefore, as shown in FIG. 1, the pulse voltage as shown in FIG. 2 from the pulse generator 1 is
A measuring circuit is used which applies a voltage to a humidity sensor 2 made of a porous sintered body made of MgCr 2 O 4 and TiO 2 and extracts a voltage corresponding to the relative humidity from an output terminal 3.
ところが、このような測定回路においては、湿
度センサ２の抵抗値が相対湿度の変化に対して第
３図に示すような関係で変化し、相対湿度が数％
のときは108Ωという非常に大きな抵抗値を示す。
このため、パルス電圧のパルス幅ｔが小さければ
小さいほど湿度センサ２の線間容量の影響によつ
て精度が悪くなる。 However, in such a measurement circuit, the resistance value of the humidity sensor 2 changes in the relationship shown in Figure 3 with respect to changes in relative humidity, and the relative humidity changes by a few percent.
When , it shows a very large resistance value of 10 8 Ω.
Therefore, the smaller the pulse width t of the pulse voltage, the worse the accuracy becomes due to the influence of the line capacitance of the humidity sensor 2.
一方、このような問題を解決するためにパルス
幅ｔを大きくすると、湿度センサ２に長時間直流
電圧を印加することになるので、特に高湿度のと
きに電気分解を起し、劣化の原因となる。 On the other hand, if the pulse width t is increased to solve this problem, a DC voltage will be applied to the humidity sensor 2 for a long time, which may cause electrolysis and deterioration, especially in high humidity. Become.
本発明はこのような相矛盾する問題を解決する
ようにした湿度測定回路を提供するものである。 The present invention provides a humidity measuring circuit that solves these contradictory problems.
以下本発明の一実施例について第４図、第５図
とともに説明する。第４図において４はパルス電
圧を出力するパルス発生器、２および３は第１図
と同一の湿度センサおよび出力端子、５は出力端
子３の電圧に応じて発振周波数が変化する電圧制
御発振器である。そして上記パルス発生器４は電
圧制御発振器５の発振周波数に応じて出力パルス
のパルス幅が制御されるように構成されている。 An embodiment of the present invention will be described below with reference to FIGS. 4 and 5. In Figure 4, 4 is a pulse generator that outputs a pulse voltage, 2 and 3 are the same humidity sensors and output terminals as in Figure 1, and 5 is a voltage controlled oscillator whose oscillation frequency changes according to the voltage at output terminal 3. be. The pulse generator 4 is configured such that the pulse width of the output pulse is controlled according to the oscillation frequency of the voltage controlled oscillator 5.
上記構成において、相対湿度が低湿度から高湿
度に変化すると、出力端子３の電圧はそれに応じ
て変化し、電圧制御発振器５の発振周波数もそれ
に応じて変化する。その結果、パルス発生器４の
パルス幅は小さくなり、湿度センサ２の電気分解
による劣化を防止する。逆に相対湿度が高湿度か
ら低湿度に変化すると、パルス幅が大きくなり、
精度の低下を防止する。第５図は上記実施例の相
対湿度とパルス幅の関係を示したものである。 In the above configuration, when the relative humidity changes from low humidity to high humidity, the voltage at the output terminal 3 changes accordingly, and the oscillation frequency of the voltage controlled oscillator 5 also changes accordingly. As a result, the pulse width of the pulse generator 4 becomes smaller, thereby preventing deterioration of the humidity sensor 2 due to electrolysis. Conversely, when the relative humidity changes from high humidity to low humidity, the pulse width increases,
Prevent loss of accuracy. FIG. 5 shows the relationship between relative humidity and pulse width in the above embodiment.
このように本発明によれば、低湿度での測定精
度を高くすると同時に高湿度領域での湿度センサ
の劣化を防止し、全体として測定範囲を広くする
ことができるという優れた効果が得られる。 As described above, according to the present invention, excellent effects can be obtained in that measurement accuracy at low humidity can be increased, while at the same time deterioration of the humidity sensor can be prevented in high humidity regions, and the measurement range can be widened as a whole.
第１図は従来例のブロツク図、第２図、第３図
はその動作説明図、第４図は本発明の一実施例を
示すブロツク図、第５図はその動作説明図であ
る。
２……湿度センサ、３……出力端子、４……パ
ルス発生器、５……電圧制御発振器。
FIG. 1 is a block diagram of a conventional example, FIGS. 2 and 3 are diagrams explaining its operation, FIG. 4 is a block diagram showing an embodiment of the present invention, and FIG. 5 is a diagram explaining its operation. 2... Humidity sensor, 3... Output terminal, 4... Pulse generator, 5... Voltage controlled oscillator.
Claims (1)
を供給するパルス発生器と、上記湿度センサの出
力に対応した発振周波数を上記パルス発生器に供
給する電圧制御発振器を有する湿度測定回路。1. A humidity measurement circuit including a humidity sensor, a pulse generator that supplies a pulse voltage to the humidity sensor, and a voltage controlled oscillator that supplies the pulse generator with an oscillation frequency corresponding to the output of the humidity sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP951779A JPS55101851A (en) | 1979-01-29 | 1979-01-29 | Humidity measuring circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP951779A JPS55101851A (en) | 1979-01-29 | 1979-01-29 | Humidity measuring circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS55101851A JPS55101851A (en) | 1980-08-04 |
| JPS638422B2 true JPS638422B2 (en) | 1988-02-23 |
Family
ID=11722443
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP951779A Granted JPS55101851A (en) | 1979-01-29 | 1979-01-29 | Humidity measuring circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS55101851A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63171878U (en) * | 1987-04-28 | 1988-11-08 |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS492596A (en) * | 1972-04-19 | 1974-01-10 | ||
| JPS5410787A (en) * | 1977-06-27 | 1979-01-26 | Yamatake Honeywell Co Ltd | Hygrometer |
-
1979
- 1979-01-29 JP JP951779A patent/JPS55101851A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS492596A (en) * | 1972-04-19 | 1974-01-10 | ||
| JPS5410787A (en) * | 1977-06-27 | 1979-01-26 | Yamatake Honeywell Co Ltd | Hygrometer |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63171878U (en) * | 1987-04-28 | 1988-11-08 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS55101851A (en) | 1980-08-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3932810A (en) | Temperature compensated combined current and voltage measuring apparatus | |
| KR880011601A (en) | Battery remaining capacity alarm | |
| US4282480A (en) | Apparatus for humidity detection | |
| JPS6026164B2 (en) | Tilt detection device | |
| JPS638422B2 (en) | ||
| US4793187A (en) | Circuit arrangement for the compensation of temperature-dependent and temperature-independent drift and for the compensation of the sensitivity of a capacitive sensor | |
| US3879657A (en) | Electrical apparatus for minimizing polarization of conductivity cell electrodes | |
| JPH057582Y2 (en) | ||
| JPS551507A (en) | Humidity detector | |
| US5119096A (en) | Analog to frequency converter with balancing compensation cycles | |
| GB1299203A (en) | Direct reading water content meter | |
| JPS635011Y2 (en) | ||
| SU1000932A1 (en) | Device for measuring phase shift | |
| JPS6236333Y2 (en) | ||
| JPH0256849B2 (en) | ||
| JP3045664B2 (en) | Electric conductivity measuring device | |
| JPH0521026Y2 (en) | ||
| JPS649581B2 (en) | ||
| JPH0527830B2 (en) | ||
| SU1356208A1 (en) | Complex conductance active component pickup for automatic matching devices | |
| SU412557A1 (en) | QUASI-ADVANCED BRIDGE FOR MEASUREMENT OF ACTIVE OR REACTIVE COMPONENT OF COMPLEX RESISTANCE | |
| JPS6318178Y2 (en) | ||
| SU391485A1 (en) | DEVICE FOR MEASURING RESISTANCE OF RESISTORS | |
| KR930004305Y1 (en) | Noise compensation circuit of signal generator | |
| JPS5587957A (en) | Voltage detection circuit |