JPS624660B2 - - Google Patents
Info
- Publication number
- JPS624660B2 JPS624660B2 JP8650481A JP8650481A JPS624660B2 JP S624660 B2 JPS624660 B2 JP S624660B2 JP 8650481 A JP8650481 A JP 8650481A JP 8650481 A JP8650481 A JP 8650481A JP S624660 B2 JPS624660 B2 JP S624660B2
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- signal
- detection
- diode
- grain
- 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
- 238000001514 detection method Methods 0.000 claims description 27
- 239000003990 capacitor Substances 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 7
- 238000012937 correction Methods 0.000 description 3
- 230000001419 dependent effect Effects 0.000 description 2
- 238000009499 grossing Methods 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 238000005259 measurement Methods 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
- G01N27/045—Circuits
- G01N27/046—Circuits provided with temperature compensation
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Description
【発明の詳細な説明】
本発明は温度補償機能を備えた穀物水分測定装
置、詳しくは、測定装置に起因する温度ドリフト
の影響を除去した穀物の含水率を測定するための
高周波式水分測定装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention provides a grain moisture measuring device with a temperature compensation function, and more specifically, a high-frequency moisture measuring device for measuring the moisture content of grain that eliminates the influence of temperature drift caused by the measuring device. Regarding.
穀物の水分値を測定するための装置として高周
波発振器を含む高周波式水分計が知られている。
この水分計においては、一定容積の穀物が電極容
器中に挿入され、電極間に高周波電圧を加えて、
穀物の水分値に依存するその静電容量を測定する
ことにより穀物の水分値に比例した高周波電圧を
検出し、この高周波電圧を検波して、直流電圧に
変換し、この直流電圧値から穀物の水分率を測定
している。しかしながら、穀物の含水率は温度依
存性を有しているので、一般にサーミスタにより
穀物の温度を検出することで、穀物の温度補正が
成されているが、高周波式水分計自体の温度ドリ
フトによる温度補正は成されていなかつた。すな
わち、高周波式水分計は被測定穀物に高周波信号
を加える高周波発振器、および穀物の水分率を測
定する為の水分測定回路を有している。この水分
測定回路をトランジスタ、ダイオード等温度依存
性を有する回路素子を使用して構成する場合、こ
れら素子に起因する温度ドリフトを補償しなけれ
ば正確な水分率の測定はできない。 A high-frequency moisture meter including a high-frequency oscillator is known as a device for measuring the moisture value of grain.
In this moisture meter, a certain volume of grain is inserted into an electrode container, and a high frequency voltage is applied between the electrodes.
By measuring the capacitance, which depends on the moisture content of the grain, a high-frequency voltage proportional to the moisture content of the grain is detected, and this high-frequency voltage is detected and converted to a DC voltage. Measuring moisture content. However, since the moisture content of grain is temperature-dependent, grain temperature correction is generally performed by detecting the grain temperature with a thermistor, but the temperature due to the temperature drift of the high-frequency moisture meter itself No corrections were made. That is, the high-frequency moisture meter has a high-frequency oscillator that applies a high-frequency signal to the grain to be measured, and a moisture measuring circuit for measuring the moisture content of the grain. When this moisture measuring circuit is configured using circuit elements having temperature dependence, such as transistors and diodes, accurate moisture content measurement cannot be performed unless temperature drift caused by these elements is compensated for.
従つて、本発明の目的は、簡単な回路構成で測
定回路自体に起因する温度ドリフトを補正するこ
とのできる高周波式穀物水分測定装置を提供する
ことである。本出願人が本出願と同日に出願した
「発振回路の温度補償機能を備えた穀物水分測定
装置」（特開昭57―200842）の明細書には発振回
路の温度ドリフトの影響を除去するための高周波
式穀物水分測定装置が記載されている。 SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a high-frequency grain moisture measuring device that can correct temperature drift caused by the measuring circuit itself with a simple circuit configuration. The specification of "Grain Moisture Measuring Apparatus Equipped with Temperature Compensation Function of Oscillation Circuit" (Japanese Patent Application Laid-Open No. 57-200842), filed by the present applicant on the same day as this application, states that in order to eliminate the influence of temperature drift of the oscillation circuit, A high-frequency grain moisture measuring device is described.
以下、本発明を添付図面に示す一実施例を参照
して詳細に説明する。 Hereinafter, the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.
第１図に示す高周波式穀物水分測定装置におい
て、１は被測定試料すなわち穀物に高周波信号を
加えるための高周波発振器、３は被測定穀物を介
在させるための一対の電極、５は穀物からの高周
波被測定信号を検出するための検出用トランジス
タであり、そのベース端子に電極３からの被測定
信号が加えられる。９は基準電源１３からの基準
電圧に基づき検出用トランジスタ５のコレクタの
直流電圧成分Ｖが一定値になるように制御するた
めの比較回路である。比較回路９の出力は検出用
トランジスタ５のベース端子に接続され、コレク
タ端子の直流成分はＶに固定されるので、トラン
ジスタ５に起因する直流分の温度ドリフトは除去
される。穀物の被測定信号および比較回路９の出
力信号により、トランジスタ５のコレクタ側のP1
点には直流電圧成分Ｖと高周波の被測定信号ＶAC
の和Ｖ＋ＶACが検出される。このように、トラン
ジスタ５および比較回路９によつて穀物の含水率
に関する検出信号を発生するための検出回路Ａが
構成されている。 In the high-frequency grain moisture measuring device shown in Fig. 1, 1 is a high-frequency oscillator for applying a high-frequency signal to the sample to be measured, that is, the grain, 3 is a pair of electrodes for intervening the grain to be measured, and 5 is a high-frequency signal from the grain. This is a detection transistor for detecting a signal to be measured, and the signal to be measured from the electrode 3 is applied to its base terminal. Reference numeral 9 denotes a comparison circuit for controlling the DC voltage component V of the collector of the detection transistor 5 to a constant value based on the reference voltage from the reference power supply 13. The output of the comparison circuit 9 is connected to the base terminal of the detection transistor 5, and the DC component at the collector terminal is fixed to V, so the temperature drift of the DC component caused by the transistor 5 is removed. P 1 on the collector side of the transistor 5 due to the measured grain signal and the output signal of the comparison circuit 9
At the point, there is a DC voltage component V and a high frequency signal under test V AC
The sum of V+V AC is detected. In this way, the transistor 5 and the comparison circuit 9 constitute a detection circuit A for generating a detection signal regarding the moisture content of grain.
１５はダイオードであり、その電圧降下Ｖfは
温度依存性を有する。ダイオード１５はそのカソ
ード側に接続された抵抗とコンデンサから成る平
滑回路と共に検波回路Ｂを構成している。ダイオ
ード１５のアノード側には第２図に示すような検
出信号Ｖ＋ＶACが加えられている。ここでＶACは
穀物の水分値を示す高周波成分である。ダイオー
ド１５のカソード端子における検出信号は（Ｖ−
Ｖf）＋ＶACとなり、Ｖfを温度補償するための温
度補償回路Ｃが必要となる。 15 is a diode, the voltage drop V f of which has temperature dependence. The diode 15 constitutes a detection circuit B together with a smoothing circuit consisting of a resistor and a capacitor connected to its cathode side. A detection signal V+V AC as shown in FIG. 2 is applied to the anode side of the diode 15. Here, V AC is a high frequency component indicating the moisture content of the grain. The detection signal at the cathode terminal of the diode 15 is (V-
V f )+V AC , and a temperature compensation circuit C is required to temperature compensate V f .
参照番号７は補償用トランジスタであり、その
コレクタ端子を直流電圧Ｖに固定するために、コ
レクタの直流電圧と基準電源１３からの基準電位
とに基づきトランジスタ７を制御する比較回路１
１が設けられている。これらの構成要素によつて
温度補償回路が形成される。１７はダイオード１
５と同一の温度特性の補償用ダイオードであり、
そのアノード側には、トランジスタ７のコレクタ
が接続されている。従つて、ダイオード１７のカ
ソード側のB2点の電位は補償信号Ｖ−Ｖfとな
る。また、ダイオード１５のカソード側に接続さ
れた平滑回路によつて高周波成分ＶACは直流成分
ＶDCに変換されるので、B1点における検出信号
は、第３図に示すとおり（Ｖ−Ｖf）＋ＶDCとな
る。 Reference number 7 is a compensation transistor, and in order to fix its collector terminal to a DC voltage V, a comparator circuit 1 controls the transistor 7 based on the DC voltage of the collector and a reference potential from a reference power supply 13.
1 is provided. These components form a temperature compensation circuit. 17 is diode 1
It is a compensation diode with the same temperature characteristics as 5,
The collector of the transistor 7 is connected to its anode side. Therefore, the potential at point B2 on the cathode side of the diode 17 becomes the compensation signal V-V f . Furthermore, the high frequency component V AC is converted into the DC component V DC by the smoothing circuit connected to the cathode side of the diode 15 , so the detection signal at point B is as shown in FIG. 3 (V-V f )+V DC .
１９は減算回路であり、B1点およびB2点の電
圧の差に基づく出力信号ＶDCを発生するものであ
る。（Ｖ−Ｖf）＋（ＶDC−（Ｖ−Ｖf）＝ＶDCであり
温度依存性の電圧成分Ｖfが除外される。ＶDCは
純粋に穀物の水分値に基づいており、この直流電
圧に基づき、穀物の含水率が表示される。すなわ
ち、ＶDCはダイオード１５の温度ドリフトを含ま
ない値であつて、ＶDCに基づけば検出信号の温度
ドリフトを除去した正確な水分率を測定すること
ができる。 Reference numeral 19 denotes a subtraction circuit that generates an output signal V DC based on the difference in voltage between one point B and two points B. (V - V f ) + (V DC - (V - V f ) = V DC , which excludes the temperature-dependent voltage component V f . V DC is purely based on the moisture value of the grain; Based on the DC voltage, the moisture content of the grain is displayed. That is, V DC is a value that does not include the temperature drift of the diode 15, and based on V DC , the accurate moisture content with the temperature drift of the detection signal removed is displayed. can be measured.
第４図は比較回路９の一実施例である。同図に
おいて、２１は演算増巾器であり、その＋入力端
子に加えられる検出信号Ｖ＋ＶACから高周波成分
ＶACを除去するコンデンサをその＋入力端子に接
続しており、演算増巾器２１の出力には直流電圧
Ｖを発生する。２３はトランジスタ５のコレクタ
端子の直流電圧成分をＶに固定するために、演算
増巾器２１の出力電圧を基準電源１３からの基準
電位と比較する制御回路であり、演算増巾器２５
を有している。また、比較回路１１は制御回路２
３と同一の回路構成を有するものである。 FIG. 4 shows one embodiment of the comparator circuit 9. In the same figure, 21 is an operational amplifier, and a capacitor for removing a high frequency component V AC from the detection signal V + V AC applied to the + input terminal is connected to the + input terminal of the operational amplifier 21. A DC voltage V is generated at the output. 23 is a control circuit that compares the output voltage of the operational amplifier 21 with the reference potential from the reference power supply 13 in order to fix the DC voltage component of the collector terminal of the transistor 5 to V;
have. Further, the comparison circuit 11 is connected to the control circuit 2.
It has the same circuit configuration as No. 3.
上記本発明の一実施例においては、温度補正回
路はトランジスタ７、比較回路１１およびダイオ
ード１７によつて構成されているが、ダイオード
１７のアノード側は一定直流電圧Ｖに保たれれば
よいので、その為の基準電源を使用してもよい。
例えば、演算増巾器２１の出力直流電圧Ｖをダイ
オード１７のアノードに加えてもよい。 In the above embodiment of the present invention, the temperature correction circuit is composed of the transistor 7, the comparison circuit 11, and the diode 17, but since the anode side of the diode 17 only needs to be maintained at a constant DC voltage V, A reference power supply for this purpose may be used.
For example, the output DC voltage V of the operational amplifier 21 may be applied to the anode of the diode 17.
第１図は本発明の一実施例の高周波式穀物水分
測定装置の回路構成図、第２図は第１図の回路構
成図中A1点の電圧波形図、第３図は同図中B1点
の電圧波形図、および第４図は第１図の比較回路
の一実施例の回路構成図である。
５，７：トランジスタ、９，１１：比較回路、
１３：基準電源、１５，１７：ダイオード、１
９：減算回路、Ａ，１，３，５，９：検出回路、
Ｂ，１５，Ｃ，Ｒ：検波回路、Ｃ，７，１１，１
７：温度補償回路。
Figure 1 is a circuit diagram of a high-frequency grain moisture measuring device according to an embodiment of the present invention, Figure 2 is a voltage waveform diagram at point A in the circuit diagram in Figure 1 , and Figure 3 is a voltage waveform diagram at point B in the diagram. A voltage waveform diagram of one point and FIG. 4 are circuit configuration diagrams of an embodiment of the comparison circuit of FIG. 1. 5, 7: transistor, 9, 11: comparison circuit,
13: Reference power supply, 15, 17: Diode, 1
9: Subtraction circuit, A, 1, 3, 5, 9: Detection circuit,
B, 15, C, R: Detection circuit, C, 7, 11, 1
7: Temperature compensation circuit.
Claims (1)
号を発生する検出回路、 前記検出信号から前記信号成分に関する検波信
号を得るため、の検波回路、 前記検波信号に含まれている温度誤差成分に相
当する信号成分を含む補償信号を発生する温度補
償回路、および 前記検波信号から前記補償信号を減算すること
によつて、温度誤差成分を除去した穀物の水分値
を示す信号を発生させるための減算回路を有する
温度補償機能を備えた高周波穀物水分測定装置。 ２ 前記検出回路は前記検出信号を発生するため
のトランジスタと、前記検出信号に含まれる直流
成分を所定の基準電位と比較して前記トランジス
タからの前記検出信号中の前記直流電圧成分が一
定値となるように前記トランジスタを制御する比
較回路を有する特許請求の範囲第１項記載の高周
波穀物水分測定装置。 ３ 前記検波回路はダイオードと前記ダイオード
に直列接続された抵抗と容量との並列回路を有す
る特許請求の範囲第１項記載の高周波穀物水分測
定装置。 ４ 前記温度補償回路は前記検出回路および前記
検波回路と実質的に同一の回路構成を有する特許
請求の範囲第１項記載の高周波穀物水分測定装
置。 ５ 前記温度補償回路は、前記検波回路のダイオ
ードと同一温度特性の補償用ダイオードを有し、
前記ダイオードのアノード側に前記検知信号の直
流電圧成分が印加される特許請求の範囲第３項記
載の高周波穀物水分測定装置。[Scope of Claims] 1. A detection circuit for generating a detection signal including a signal component based on the moisture value of grain; a detection circuit for obtaining a detection signal related to the signal component from the detection signal; a temperature compensation circuit that generates a compensation signal including a signal component corresponding to a temperature error component, and a temperature compensation circuit that generates a signal indicating a grain moisture value from which the temperature error component is removed by subtracting the compensation signal from the detected signal; High frequency grain moisture measuring device with temperature compensation function with subtraction circuit for generating. 2. The detection circuit includes a transistor for generating the detection signal, and compares a DC component included in the detection signal with a predetermined reference potential to determine that the DC voltage component in the detection signal from the transistor is a constant value. 2. The high-frequency grain moisture measuring device according to claim 1, further comprising a comparison circuit for controlling said transistor so that the amount of moisture in grain is determined. 3. The high-frequency grain moisture measuring device according to claim 1, wherein the detection circuit includes a parallel circuit including a diode and a resistor and a capacitor connected in series with the diode. 4. The high-frequency grain moisture measuring device according to claim 1, wherein the temperature compensation circuit has substantially the same circuit configuration as the detection circuit and the detection circuit. 5. The temperature compensation circuit includes a compensation diode having the same temperature characteristics as the diode of the detection circuit,
4. The high-frequency grain moisture measuring device according to claim 3, wherein the DC voltage component of the detection signal is applied to the anode side of the diode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8650481A JPS57200843A (en) | 1981-06-05 | 1981-06-05 | Cereals moisture measuring device equipped with temperature compensating function |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8650481A JPS57200843A (en) | 1981-06-05 | 1981-06-05 | Cereals moisture measuring device equipped with temperature compensating function |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57200843A JPS57200843A (en) | 1982-12-09 |
| JPS624660B2 true JPS624660B2 (en) | 1987-01-31 |
Family
ID=13888805
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8650481A Granted JPS57200843A (en) | 1981-06-05 | 1981-06-05 | Cereals moisture measuring device equipped with temperature compensating function |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57200843A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04203556A (en) * | 1990-11-29 | 1992-07-24 | Hino Motors Ltd | Transmission |
-
1981
- 1981-06-05 JP JP8650481A patent/JPS57200843A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04203556A (en) * | 1990-11-29 | 1992-07-24 | Hino Motors Ltd | Transmission |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57200843A (en) | 1982-12-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7403020B2 (en) | Method and device for measuring capacitances | |
| US4282480A (en) | Apparatus for humidity detection | |
| US4272718A (en) | Moisture meter | |
| JPS624660B2 (en) | ||
| Enke et al. | A versatile and inexpensive controlled potential polarographic analyzer | |
| JPS6215415A (en) | Detector for ink level | |
| JP4072030B2 (en) | Sensor capacity detection device and sensor capacity detection method | |
| JPS6156460B2 (en) | ||
| JPS59780B2 (en) | measuring device | |
| JP2003156524A (en) | Potential fixing apparatus and potential fixing method | |
| JP2862761B2 (en) | Capacitance type alcohol concentration measurement device | |
| JPS6152945B2 (en) | ||
| US4047105A (en) | Method and apparatus for providing an output indication proportional to the moisture content of particulate material | |
| JPH0722036Y2 (en) | High voltage power supply | |
| JP2648966B2 (en) | Vacuum pressure gauge | |
| SU61680A1 (en) | Lamp voltmeter | |
| JPS6313486Y2 (en) | ||
| JPH0746067A (en) | Voltage-frequency converting method | |
| JP2657279B2 (en) | How to determine the polarity of electrolytic capacitors | |
| SU612185A1 (en) | Arrangement for measuring dynamic resistance of quartz resonators | |
| SU993365A1 (en) | Device for measuring internal resistance of electrochemical current source | |
| SU1427282A1 (en) | Voltamperograph | |
| SU709990A1 (en) | Electronic moisture-content meter | |
| KR960013754B1 (en) | Condenser test circuit | |
| KR20000000362A (en) | Nonlinearity compensation method and its apparatus of capacitive sensor controller sensing the position precisely |