JPS60213822A - Liquid-level measuring device - Google Patents
Liquid-level measuring deviceInfo
- Publication number
- JPS60213822A JPS60213822A JP59069858A JP6985884A JPS60213822A JP S60213822 A JPS60213822 A JP S60213822A JP 59069858 A JP59069858 A JP 59069858A JP 6985884 A JP6985884 A JP 6985884A JP S60213822 A JPS60213822 A JP S60213822A
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- liquid level
- electrodes
- terminal
- circuits
- 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.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
- G01F23/26—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields
- G01F23/263—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields by measuring variations in capacitance of capacitors
- G01F23/266—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields by measuring variations in capacitance of capacitors measuring circuits therefor
Abstract
Description
【発明の詳細な説明】 るようにした液位計測装置に関する。[Detailed description of the invention] The present invention relates to a liquid level measuring device configured to
従来液位計測装置としては、フロートを用いたものや、
静電容量式で信号をアナログ量で取り出す方式のものが
あった。・
しかし、フロート式は機械的構成部を備えるため、故障
が起きた時修理が困難であり、また静電容量を用いたア
ナ筒グ式の方法では高精度のものとするには極めて高価
につくという欠点がある。Conventional liquid level measuring devices include those using floats,
There was a capacitive type that extracted the signal in analog form.・However, since the float type has mechanical components, it is difficult to repair when a failure occurs, and the analog tube type method using capacitance is extremely expensive to achieve high precision. There is a drawback that it sticks.
本発明は静電容量の違いにより検出された液位な直接デ
ジタル量で取り出せるようにしたもので、機械的構成部
分が全くな（、高精度の液位計測装置を安価に提供でき
るようにした。The present invention enables the liquid level detected by the difference in capacitance to be taken out directly in digital quantities, and there are no mechanical components (it is possible to provide a high-precision liquid level measuring device at a low cost). .
以下本発明を実施例図に基いて説明する。The present invention will be explained below based on embodiment figures.
第１図において、１底面が閉塞した保護筒１に、液流入
口２ａを下部に有する電極収納管２が貫通し、同電極収
納管２内には相対向したコンデンサ用の一対の電極３ａ
と８ｂ，４ａと４ｂ，５ａと５ｂ，６ａと６ｂ，７ａと
７ｂを設は文ある。各電極の一方の極３ｂ〜７ｂは保護
筒１内で全て接地され、他方の極３ａ〜７ａは、保護筒
ｌ内にあるフリップフロップ回路８， ９， １０，
１１， １２の各クロック端ＣＫと、抵抗１３， １４
， １５， １６， １７を介してクロック入力端ＣＫ
Ｉに接続されている。In FIG. 1, an electrode storage tube 2 having a liquid inlet 2a at the bottom passes through a protection tube 1 with a closed bottom, and a pair of electrodes 3a for a capacitor facing each other are inside the electrode storage tube 2.
and 8b, 4a and 4b, 5a and 5b, 6a and 6b, 7a and 7b. One pole 3b to 7b of each electrode is all grounded inside the protective tube 1, and the other pole 3a to 7a are connected to flip-flop circuits 8, 9, 10, inside the protective tube 1.
Each clock terminal CK of 11 and 12 and resistors 13 and 14
, 15, 16, 17 via the clock input terminal CK
Connected to I.
また各フリップフロップ回路のＤ入力端は、フリップフ
ロップ回路８のＤ入力端だけが接地され、他は全て１つ
前の７リツプ７０ツブ回路のＱ出力端に接続されており
、これによりシフトレジスタを形成している。In addition, only the D input terminal of the flip-flop circuit 8 is grounded, and the other D input terminals of each flip-flop circuit are connected to the Q output terminal of the previous 7-lip 70-tub circuit. is formed.
イニシャル入力端ＩＮＴには、フリップフロップ回路８
のみがセット入力端Ｓを接続しであるが、他のフリップ
フロップ回路は全てリセット端Ｒを接続してあり、レベ
ル検出端ＬＶＥは各抵抗２２．２３．２４．２５と、こ
れらに直列に接続されたダイオード１８．１９．２０．
２１を介して各７リツプフロツプ回路のＱ端に接続しで
ある。The initial input terminal INT has a flip-flop circuit 8.
Only one flip-flop circuit has the set input terminal S connected, but all the other flip-flop circuits have the reset terminal R connected, and the level detection terminal LVE is connected in series with each resistor 22, 23, 24, 25. diode 18.19.20.
21 to the Q terminal of each of the seven lip-flop circuits.
次に本発明の回路動作について説明する。Next, the circuit operation of the present invention will be explained.
第１図において、電極６，７が液中に没していると、空
中にある電極３．４．５に比べて電極６゜７の静電容量
は、液体の比誘電率ｔεＳとすると６８倍となる。In Figure 1, when the electrodes 6 and 7 are submerged in the liquid, the capacitance of the electrode 6°7 is 68, compared to the electrode 3.4.5 in the air, assuming the relative dielectric constant tεS of the liquid. It will be doubled.
ここでクロック入力端ＣＫＩよりクロックパルスを入力
すると、空気の静電容量を有する電極３、４．５に接続
されたａ、 ｂ、 ｃ点の波形は、第２図のように元の
クロックパルスよりｔ８時間遅れたクロック波形となる
。ところが液により増大した静電容量を持つ電極６，７
に接続されたｄ、ｅ点の波形は、同じく第２図のように
元のクロック波形よりさらＫｔ１＋ｔｓ時間遅れた波形
を示す。Here, when a clock pulse is input from the clock input terminal CKI, the waveforms at points a, b, and c connected to the electrodes 3 and 4.5, which have air capacitance, are the original clock pulse as shown in Figure 2. The clock waveform is delayed by time t8. However, the electrodes 6 and 7 have increased capacitance due to the liquid.
The waveforms at points d and e, which are connected to , show waveforms that are further delayed by Kt1+ts from the original clock waveform, as shown in FIG.
このためフリップフロップ回路１１．１２はフリップフ
ロップ回路８．９．１０より常にｔまたけ遅れたクロッ
クを受けることになる。Therefore, the flip-flop circuits 11.12 always receive a clock delayed by t from the flip-flop circuits 8.9.10.
最初イニシャル入力端ＩＮＴにイニシャルセットパルス
を入力すると、第３図に示すように７リツプ７０クプ回
路８が七ットされ、他は全てリセットされろ。次にＣＫ
Ｉより１番目のクロックＰ１が入力されると、フリップ
フロップ回路８の状態はフリップフロップ回路９に移動
し、以後クロック入力がＰｓ、Ｐｓと入力される度に下
段のフリップフロップ回路にＱ出力状態がシフトされて
行（。ところが７リツプフロツプ回路１１のクロック端
ＣＫＫ接続されている電極は液中に没しているため静電
容量が多（、実際に７リツプフＨｙプ回路１１のｃＨに
入力されるクロックパルスはフリップフロップ回路１０
に入力されたものよりもｔ！秒はと遅れて入力されてく
る。これがＰｒであり、Ｐｒが入力されてくる時点では
すでにフリップフロップ回路１０はＱ出力状態になって
いるためフリップフレ２１回路１１のＤ端は高レベルで
あり、したがって１２秒後に７リツプフロツグ回路１１
もＱ出力状態になりてしまう。When an initial set pulse is first input to the initial input terminal INT, the 7-rip 70-cup circuit 8 is set to 7 as shown in FIG. 3, and everything else is reset. Next, C.K.
When the first clock P1 is input from I, the state of the flip-flop circuit 8 is transferred to the flip-flop circuit 9, and thereafter, every time the clock input is input as Ps and Ps, the Q output state is changed to the lower flip-flop circuit. is shifted to the row (. However, since the electrode connected to the clock terminal CKK of the 7 lip flop circuit 11 is submerged in the liquid, it has a large capacitance (actually input to ch of the 7 lip flop circuit 11. The clock pulse is sent to the flip-flop circuit 10.
t! Seconds are input with a delay. This is Pr, and since the flip-flop circuit 10 is already in the Q output state when Pr is input, the D terminal of the flip-flop circuit 11 is at a high level.
also enters the Q output state.
このためクロックパルスＰｆ入力後Ｐ３人力までのｔＢ
・秒間、液面直前と直後の２つの７リツプフロツ、プ回
路が同時にＱ出力状態となる。この状態を検出すること
により液位なめることができる。この検出はレベル検出
端ＬＶＥから行なっており、そのレベル検出回路を第４
図に基いて説明する。Therefore, tB up to P3 human power after inputting clock pulse Pf
・For a second, the two 7-lip flop circuits immediately before and immediately after the liquid level are in the Q output state at the same time. By detecting this state, the liquid level can be determined. This detection is performed from the level detection terminal LVE, and the level detection circuit is connected to the fourth
This will be explained based on the diagram.
同図にはオペアンプを用いた加算回路を示してあり、抵
抗の値が全て等しいとみなすと、出力ｖ０は、
Ｖｏ ＝（Ｖｓ ＋ Ｖａ ＋ Ｖａ ＋ Ｖ４ ）と
なり、■ｏ端電位は複数電圧の加算の和となっている。The figure shows an adder circuit using an operational amplifier.If all resistance values are assumed to be equal, the output v0 will be Vo = (Vs + Va + Va + V4), and the potential at the o end will be the sum of multiple voltages. It is the sum of additions.
通常７リツプ７０ッグ回路８〜１２は１個ずっＱ出力状
態となるためＶｏの値も定まったものとなるが、水面付
近の電極に接続された２つのフリップフロップ回路が同
時出力状態になるとＶ。Normally, one of the 7-rip-flop circuits 8 to 12 is in the Q output state, so the value of Vo is also fixed, but if the two flip-flop circuits connected to the electrode near the water surface are in the simultaneous output state, V.
出力は変化するので、これを検出回路２６で検出する。Since the output changes, this is detected by the detection circuit 26.
電極間のピッチをＰｂ≠＃４、イニシャルセット後検出
回路２６で同時出力状態が検知されるまでに７リツプ７
四ツブ回路に加えたクロックパルス数をｎ、基準点Ｐａ
から液面までの相離をＬとすると、
Ｌ ＝ ｎＰ
となるので、この演算を行なう回路を設けることにより
液位な算出できる。The pitch between the electrodes is Pb≠#4, and after the initial setting, it takes 7 rips 7 before the simultaneous output state is detected by the detection circuit 26.
The number of clock pulses applied to the four-tube circuit is n, and the reference point Pa
Letting L be the phase separation from the liquid level to the liquid level, L = nP. Therefore, by providing a circuit for performing this calculation, the liquid level can be calculated.
次に計測値を遠方に伝送する手段を第５〜７図によって
説明する。Next, means for transmitting measured values to a distant place will be explained with reference to FIGS. 5 to 7.
第５図において、２７は水晶発振子等を用Ｌミたクロッ
クパルス発生回路、２８は計測制御回路であり、クロッ
クパルスを入力して一定の時間割に従りてパルスを発生
する。発生するパルスは、ＩＴσ端からはイニシャルセ
ットパルス、国からはマークパルス、ＳＴＡ端からはス
タートパルスである。まず制御回路２８がＩＴ◇端によ
りイニシャルセラ） パルスを出力するとフリップフロ
ップ回路群が初期化される。次にＭＫｍより長いマーク
信号検出後さし、同パルスはケ−）２９を通りて受信側
Ｐに行き、同時にＳＴＡ端よりのパルスにより制御用フ
リップフロップ回路３１がＱ出力状態となりてＡＮＤゲ
ート３０より発振器２７よりのクロックパルスがＣＫＩ
Ｋ出力される。このりはツクパルスは同時にデータパル
スとして受信側Ｐにも出力される。やがて検出回路２６
により水面が検出されると、ＳＴＰ端よりストップパル
スが出力され、制御用フリラグフロップ回路３１がＱ出
力状態となり、クロックパルスの出力は停止する。一方
受信側が受けとるパルスを示したのが第６図で、１周期
内忙マークパルスとデータパルスがあり、これを受信側
では第７図に示すように、マーク信号検出後、データパ
ルスの数を計数し、スペース信号を検出した時点のパル
ス数にピッチＰを掛ければ液位が算出される。これによ
り液位表示の更新を行ない、以後同じ操作を行なうこと
で常に最新の液位な知ることができるようになっている
。In FIG. 5, 27 is a clock pulse generation circuit using a crystal oscillator or the like, and 28 is a measurement control circuit which inputs clock pulses and generates pulses according to a fixed time schedule. The pulses generated are an initial set pulse from the ITσ end, a mark pulse from the country, and a start pulse from the STA end. First, when the control circuit 28 outputs an initial cell pulse from the IT◇ terminal, the flip-flop circuit group is initialized. Next, after detecting a mark signal longer than MKm, the same pulse passes through K) 29 to the receiving side P, and at the same time, the control flip-flop circuit 31 enters the Q output state due to the pulse from the STA terminal, and the AND gate 30 Therefore, the clock pulse from the oscillator 27 becomes CKI.
K is output. This pulse is also output to the receiving side P at the same time as a data pulse. Eventually the detection circuit 26
When the water surface is detected, a stop pulse is output from the STP end, the control free lag flop circuit 31 enters the Q output state, and the output of the clock pulse is stopped. On the other hand, Fig. 6 shows the pulses received by the receiving side. There are busy mark pulses and data pulses within one cycle, and the receiving side calculates the number of data pulses after detecting the mark signal as shown in Fig. 7. The liquid level is calculated by counting and multiplying the number of pulses at the time the space signal is detected by the pitch P. This allows the liquid level display to be updated, and by performing the same operation in the future, you can always know the latest liquid level.
以上のように本発明によれば、簡単な回路により正確な
液位なデジタル値で検出することができ、クロックパル
スをデータパルスとして直接送信することＫより液位デ
ータを送信回路等で処理する手間が省ける利点がある。As described above, according to the present invention, accurate liquid level digital values can be detected using a simple circuit, and rather than directly transmitting clock pulses as data pulses, the liquid level data is processed by a transmitting circuit, etc. This has the advantage of saving time and effort.
なお第８図は液位計測回路と電極群とを１個・の保護筒
に設けず、分離して別々（した他の実施例を示す。Note that FIG. 8 shows another embodiment in which the liquid level measuring circuit and the electrode group are not provided in one protective tube, but are separated.
また電極の構造は、第９図に示すように一様な導体３５
を内側に設けた円筒３４内に、電極板３７を所要ピッチ
で表面に設けた筒３６を設けた構造のものとするばあい
もある。さらに第１０図に示すように、導体３５はタン
ク側壁に設け、電極板３７は、導体３５側タンク内側壁
近くに立設したボスト３６へ所定ピッチで設けて導体３
５と対向させるようにするばあいもある。The structure of the electrode is a uniform conductor 35 as shown in FIG.
In some cases, the structure is such that a cylinder 36 having electrode plates 37 provided at a required pitch on the surface thereof is provided in a cylinder 34 having an electrode plate 37 provided on the inside thereof. Furthermore, as shown in FIG. 10, the conductor 35 is provided on the side wall of the tank, and the electrode plates 37 are provided at a predetermined pitch on the bosses 36 that are erected near the inner wall of the tank on the conductor 35 side.
In some cases, it is made to face 5.
第１図は本発明に係る液位計測装置の一例を示す回路図
、第２図はクロックパルス波形図、第３図はクロックパ
ルスとフリップフロップ回路の出力との関係を示す出力
波形図、第４図＆ニレベル検出回路図、第５図は信号伝
送回路図、第６図は送信データの出方波形図、第７図は
計測データを処理する方法を示すフローチャート、第８
図は電極と計測回路とを別々にしてタンクに取り付けた
状態を示す図、第９図と第１０図は電極構造の他の実施
例を示す図である。
図 中
ｌ 保護筒 ２ 電極収納管
２ａ 液流入口 ３，４．５．６．７ 電 極８．９．
１０．１１，１２ フリラグフロップ回路１３．１４，
１５，１６，１７，２２，２３，２４，２５抵抗１８、
１９．２０．２１ ダイオード ２６ 検出回路２７
発振器 ２８ 制御回路
２９、３０ ゲート回路 ３１ 制御用フリップ７０ツ
ブ回路３２ タ／り ３３ 液位計測回路
出願人 東京計装株式会社
第１ ｉ＊１
第８図
１１
第９図
第１０妥１
６FIG. 1 is a circuit diagram showing an example of a liquid level measuring device according to the present invention, FIG. 2 is a clock pulse waveform diagram, FIG. 3 is an output waveform diagram showing the relationship between the clock pulse and the output of a flip-flop circuit, and FIG. Figure 4 & two-level detection circuit diagram, Figure 5 is a signal transmission circuit diagram, Figure 6 is a waveform diagram of how the transmitted data is output, Figure 7 is a flowchart showing the method of processing measurement data, Figure 8
The figure shows a state where the electrode and the measurement circuit are separated and attached to the tank, and FIGS. 9 and 10 are diagrams showing other embodiments of the electrode structure. Figure middle l Protective tube 2 Electrode storage tube 2a Liquid inlet 3, 4.5.6.7 Electrode 8.9.
10.11, 12 Free lag flop circuit 13.14,
15, 16, 17, 22, 23, 24, 25 resistance 18,
19.20.21 Diode 26 Detection circuit 27
Oscillator 28 Control circuit 29, 30 Gate circuit 31 Control flip 70 tube circuit 32 T/R 33 Liquid level measurement circuit Applicant Tokyo Keiso Co., Ltd. No. 1 i*1 Fig. 8 11 Fig. 9 Fig. 10 1 6
Claims (1)
るようタンク内に所定ピッチで垂直に設けられた静電容
量を有する複数の電極、これら各電極に対応するシフト
レジスタを構成するフリップフロップ回路の各りｐツク
端とクロックパルスを出力するクロック入力端に前記各
電極を接続し、各７リツプ７ｏツブ回路の出力を検知す
る液位計測回路、とを備えてなる液位計測装置。A conductor provided vertically within the tank, a plurality of electrodes having capacitance provided vertically within the tank at a predetermined pitch to face the conductor, and flip-flops forming a shift register corresponding to each of these electrodes. A liquid level measuring device comprising: a liquid level measuring circuit for detecting the output of each 7-lip, 7-o-tub circuit, with each of the electrodes connected to each of the circuit's pin terminals and a clock input terminal for outputting clock pulses.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59069858A JPS60213822A (en) | 1984-04-07 | 1984-04-07 | Liquid-level measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59069858A JPS60213822A (en) | 1984-04-07 | 1984-04-07 | Liquid-level measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60213822A true JPS60213822A (en) | 1985-10-26 |
| JPH0246885B2 JPH0246885B2 (en) | 1990-10-17 |
Family
ID=13414922
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59069858A Granted JPS60213822A (en) | 1984-04-07 | 1984-04-07 | Liquid-level measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60213822A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0587728A1 (en) * | 1991-05-29 | 1994-03-23 | Lee/Maatuk Engineering, Inc. | Digital level sensing probe system |
| EP1744132A1 (en) * | 2005-07-11 | 2007-01-17 | Siemens Milltronics Process Instruments Inc. | Capacitive level sensor with a plurality of segments comprising each a capacitor and a circuit |
| CN105572479A (en) * | 2015-11-27 | 2016-05-11 | 贵州铜仁高新区科创互联生产力促进中心 | Circuit module for capacitor capacity measurement and capable of realizing stacked expansion and liquid level height detection circuit convenient to expand |
| WO2017189009A1 (en) | 2016-04-29 | 2017-11-02 | Hewlett-Packard Development Company, L.P. | Printing apparatus and methods for detecting fluid levels |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007218740A (en) * | 2006-02-16 | 2007-08-30 | Taiheiyo Cement Corp | Liquid level sensor device, concrete product, and submergence state detection system |
-
1984
- 1984-04-07 JP JP59069858A patent/JPS60213822A/en active Granted
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0587728A1 (en) * | 1991-05-29 | 1994-03-23 | Lee/Maatuk Engineering, Inc. | Digital level sensing probe system |
| EP0587728A4 (en) * | 1991-05-29 | 1994-04-27 | Lee/Maatuk Engineering, Inc. | |
| EP1744132A1 (en) * | 2005-07-11 | 2007-01-17 | Siemens Milltronics Process Instruments Inc. | Capacitive level sensor with a plurality of segments comprising each a capacitor and a circuit |
| WO2007006788A1 (en) * | 2005-07-11 | 2007-01-18 | Siemens Milltronics Process Instruments, Inc. | Capacitive level sensor with a plurality of segments comprising each a capacitor and a circuit |
| CN105572479A (en) * | 2015-11-27 | 2016-05-11 | 贵州铜仁高新区科创互联生产力促进中心 | Circuit module for capacitor capacity measurement and capable of realizing stacked expansion and liquid level height detection circuit convenient to expand |
| WO2017189009A1 (en) | 2016-04-29 | 2017-11-02 | Hewlett-Packard Development Company, L.P. | Printing apparatus and methods for detecting fluid levels |
| CN109070617A (en) * | 2016-04-29 | 2018-12-21 | 惠普发展公司，有限责任合伙企业 | For detecting the printing equipment and method of liquid level |
| US20190126631A1 (en) * | 2016-04-29 | 2019-05-02 | Hewlett-Packard Development Company, L.P. | Printing apparatus and methods for detecting fluid levels |
| EP3448688A4 (en) * | 2016-04-29 | 2019-12-25 | Hewlett-Packard Development Company, L.P. | Printing apparatus and methods for detecting fluid levels |
| US10926548B2 (en) | 2016-04-29 | 2021-02-23 | Hewlett-Packard Development Company, L.P. | Printing apparatus and methods for detecting fluid levels |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0246885B2 (en) | 1990-10-17 |
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| EXPY | Cancellation because of completion of term |