JPH0472177B2 - - Google Patents
Info
- Publication number
- JPH0472177B2 JPH0472177B2 JP58113722A JP11372283A JPH0472177B2 JP H0472177 B2 JPH0472177 B2 JP H0472177B2 JP 58113722 A JP58113722 A JP 58113722A JP 11372283 A JP11372283 A JP 11372283A JP H0472177 B2 JPH0472177 B2 JP H0472177B2
- Authority
- JP
- Japan
- Prior art keywords
- flow rate
- value
- time
- measured value
- measurement
- 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 - Lifetime
Links
- 238000005259 measurement Methods 0.000 claims description 42
- 239000012530 fluid Substances 0.000 claims description 6
- 239000012528 membrane Substances 0.000 description 8
- 235000014676 Phragmites communis Nutrition 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F3/00—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow
- G01F3/02—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow with measuring chambers which expand or contract during measurement
- G01F3/20—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow with measuring chambers which expand or contract during measurement having flexible movable walls, e.g. diaphragms, bellows
- G01F3/22—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow with measuring chambers which expand or contract during measurement having flexible movable walls, e.g. diaphragms, bellows for gases
- G01F3/227—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow with measuring chambers which expand or contract during measurement having flexible movable walls, e.g. diaphragms, bellows for gases characterised by the means for transfer of membrane movement information to indicating means
Description
【発明の詳細な説明】
産業上の利用分野
本発明は流体の流量測定に関し、特に単位時間
当りの流量を測定することを目的とした流量測定
装置に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to measuring the flow rate of fluid, and more particularly to a flow rate measuring device for measuring the flow rate per unit time.
従来例の構成とその問題点
従来の流体の流量装置としては、例えば、いわ
ゆる膜式のガスメータがある。このガスメータは
例えば、２枚の膜で仕切れた４つの計量室と、膜
の移動を伝達するリンク機構と、リンク機構を介
して駆動されるバルブ、指示部とより成る。膜が
一往復する都度ガスメータの大きさ毎に定めた単
位計量体積が計測される。ガスメータの計測値は
指示部にて表示されるが、周知の如く、この指示
部はメータを通過するガス量の積算値を指示し、
単位時間当りの流量を指示するものではない。2. Description of the Related Art Structures of Conventional Examples and Their Problems As a conventional fluid flow rate device, there is, for example, a so-called membrane type gas meter. This gas meter consists of, for example, four measuring chambers partitioned by two membranes, a link mechanism that transmits movement of the membranes, a valve driven via the link mechanism, and an indicator. Each time the membrane moves back and forth, a unit measurement volume determined for each gas meter size is measured. The measured value of the gas meter is displayed on the indicator, and as is well known, this indicator indicates the integrated value of the amount of gas passing through the meter.
It does not indicate the flow rate per unit time.
上述したガスメータの回転軸に永久磁石を円周
の一部に取付けた円盤と、前記永久磁石の磁界を
検出するホールICとで構成した流量センサと、
この流量センサからの流量パルスをカウントし一
分ごとに平均流量を計算する装置が知られてい
る。この装置では、所定時間（１分間）のパルス
数をカウントしているから、所定時間内に流量変
化があれば、その回の平均流量は、変化前の流量
QPと変化後の流量QP+1との時間平均となり、変
化後の流量を正確に計測できない。 A flow rate sensor composed of a disk in which a permanent magnet is attached to a part of the circumference of the rotating shaft of the gas meter described above, and a Hall IC that detects the magnetic field of the permanent magnet;
A device is known that counts flow rate pulses from this flow rate sensor and calculates the average flow rate every minute. This device counts the number of pulses in a predetermined period of time (1 minute), so if there is a change in flow rate within a predetermined period of time, the average flow rate for that time is the flow rate before the change.
It becomes a time average of Q P and the flow rate after the change Q P+1 , and the flow rate after the change cannot be measured accurately.
発明の目的
本発明は上記従来の欠点を解消するもので、流
体の流量変化後の流量を単位時間当り流量として
正確に計測することを目的とする。OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, and aims to accurately measure the flow rate of a fluid after a change in flow rate as a flow rate per unit time.
発明の構成
上記目的を達成するため、本発明の流量測定装
置は、流体供給ライン中に設けられ、単位計量体
積を計量するつど流量パルスを発信する流量セン
サと、前記流量パルスを入力とし、この流量パル
スに基づき単位時間当りの流量を演算する演算処
理装置とを備え、前記演算処理装置は、少くとも
前回の測定値を記憶する記憶部と、今回の測定値
に所定の係数を乗ずる演算手段と、その結果と、
前記記憶部に記憶している前回測定値と今回の測
定値との差の絶対値とを比較する比較手段と、前
記今回測定値に所定の係数を乗じた演算結果が前
記差の絶対値よりも大きいときに、今回測定値と
記憶部に記憶されている測定値とより単位時間当
りの流量演算し、前記今回測定値に所定の係数を
乗じた演算結果が前記差の絶対値よりも小さい時
に前記記憶部に記憶されている測定値を消去する
流量演算手段を備えたものであり、今回測定値所
定演算結果は、一定流量を流した場合に生ずる測
定毎のばらつき等を考慮した許容変動巾を示し、
この許容変動巾以内であれば変化なしとして流量
を演算するから、もしも流量変化が生じ、今回測
定値が許容変動巾よりも大きくなれば変化ありと
し、測定値が許容変動巾以内になつたとき流量を
演算し、その演算結果は極めて正確な単位時間当
り流量となるという効果を有するものである。Composition of the Invention In order to achieve the above object, the flow rate measuring device of the present invention includes a flow rate sensor that is installed in a fluid supply line and that emits a flow rate pulse every time a unit measurement volume is measured, and a flow rate sensor that receives the flow rate pulse as an input. a calculation processing device that calculates the flow rate per unit time based on the flow rate pulse; the calculation processing device includes a storage unit that stores at least the previous measurement value; and calculation means that multiplies the current measurement value by a predetermined coefficient. and the result,
a comparison means for comparing the absolute value of the difference between the previous measured value and the current measured value stored in the storage unit; is also large, the flow rate per unit time is calculated from the current measurement value and the measurement value stored in the storage unit, and the calculation result of multiplying the current measurement value by a predetermined coefficient is smaller than the absolute value of the difference. The device is equipped with a flow rate calculation means that erases the measured value stored in the storage section, and the predetermined calculation result of the current measured value is an allowable variation that takes into account variations in each measurement that occur when a constant flow rate is flowed. Show the width,
If the flow rate is within this allowable fluctuation range, the flow rate is calculated assuming that there is no change, so if a flow rate change occurs and the current measured value is larger than the allowable fluctuation range, it is assumed that there has been a change, and when the measured value falls within the allowable fluctuation range. The flow rate is calculated, and the result of the calculation is an extremely accurate flow rate per unit time.
実施例の説明
以下、本発明の一実施例につて、図面に基づい
て説明する。DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.
第１図において、１は流量センサで、ガス供給
ライン中に設けられており、膜式ガスメータ２
と、膜式ガスメータ２の膜またはリンク機構に永
久磁石を設け、膜の一往復を前記永久磁石の磁界
の変化として検出する磁界検出器であるリードス
イツチ３とで構成する。リードスイツチ３は、メ
ータ２が単位計量体積を計量する都度一回オンオ
フし、このリードスイツチ３のオフからオンへの
変化が流量パルスとして発信される。４は演算処
理装置で、流量パルスの時間間隔を測定するタイ
マ５と、過去に測定した時間間隔を記憶する記憶
部７を有し、タイマ５の測定値と記憶部７に記憶
している過去の測定値とから単位時間当りの流量
を演算する演算処理部６とから構成する。演算処
理部は、さらに、今回の測定値に所定の演算を施
す演算手段と、その結果と、前回測定値と今回測
定値の差の絶対値を比較する比較手段と、前記演
算結果が大なるとき今回測定値と記憶部の測定値
とから単位時間当りの流量を演算する流量演算手
段を備えている。演算処理部６の典型的な例はマ
イクロコンピユータであつて、時間計測機能を有
するマイクロコンピユータを使用する場合には、
タイマ５をマイクロコンピユータに内蔵させるこ
とができる。 In Fig. 1, 1 is a flow rate sensor, which is installed in the gas supply line, and a membrane gas meter 2.
A permanent magnet is provided on the membrane or link mechanism of the membrane gas meter 2, and a reed switch 3 is a magnetic field detector that detects one round trip of the membrane as a change in the magnetic field of the permanent magnet. The reed switch 3 is turned on and off once every time the meter 2 measures a unit measurement volume, and this change of the reed switch 3 from off to on is transmitted as a flow rate pulse. Reference numeral 4 denotes an arithmetic processing unit, which has a timer 5 for measuring time intervals of flow rate pulses and a storage section 7 for storing previously measured time intervals. and an arithmetic processing unit 6 that calculates the flow rate per unit time from the measured value of . The arithmetic processing unit further includes a calculation means that performs a predetermined calculation on the current measurement value, a comparison device that compares the result with the absolute value of the difference between the previous measurement value and the current measurement value, and a comparison unit that performs a predetermined calculation on the current measurement value. A flow rate calculation means is provided for calculating the flow rate per unit time from the current measurement value and the measurement value in the storage section. A typical example of the arithmetic processing unit 6 is a microcomputer, and when using a microcomputer with a time measurement function,
The timer 5 can be built into the microcomputer.
以下上記構成における作用について説明する。
メータ２が単位計量体積を計量するづとリードス
イツチ３がオフからオンになる流量パルスを発信
する。流量パルスの時間間隔が、タイマ５によつ
て測定され、測定値が演算処理部に入力される。
演算処理部６は、測定時間間隔が所定の時間（例
えば20秒）以下であるか否かを比較する。もしも
20秒以下であれば、一定流量を流した場合の測定
時間のばらつき等を考慮した一定の係数α（例え
ば１％）を測定値に乗ずる。式で表せば、測定時
間をTP、係数をαとすれば、α・TPとなる。 The operation of the above configuration will be explained below.
When the meter 2 measures a unit measurement volume, the reed switch 3 emits a flow pulse that turns from off to on. The time interval of the flow rate pulses is measured by the timer 5, and the measured value is input to the arithmetic processing section.
The arithmetic processing unit 6 compares whether the measurement time interval is less than or equal to a predetermined time (for example, 20 seconds). If
If it is 20 seconds or less, the measured value is multiplied by a certain coefficient α (for example, 1%) that takes into account variations in measurement time when a constant flow rate is applied. Expressed in a formula, if the measurement time is T P and the coefficient is α, then α·T P is obtained.
次に記憶部に記憶している過去の測定値のうち
最新のものすなわち前回測定値TP-1と今回測定
値TPとの差の絶対値｜TP-1−TP｜を演算する。
次に△TP＝α・TPと上述の｜TP-1−TP｜とを比
較し、△TP≧｜TP-1−TP｜であれば変化なしと
して、記憶部に記憶している過去の所定数の測定
値と、今回の測定値とから平均値Pを求める。
例えば前々回、前回と今回との測定値（すなわち
３回の平均）を求めるには、（TP-2＋TP-1＋
TP）／３＝TPと演算する。次にこうして求めた
平均時間間隔Pと、メータの単位計量体積Fuと
から、単位時間当りの流ｑはFu／TPにより演算
し、その結果を流量ｑとして出力する。もしも△
TP＝ｄ・TP＜｜TP-1−TP｜であれば、流量変化
有として、変化有信号qcとして出力するととも
に、記憶部７のデータを全て消去する。このよう
にして、記憶部７に記憶している測定値と今回の
測定値との回数和が所定回数に達し（例えば３
回）、前回の測定値と今回の測定値とが上述した
関係を満足する（△TP＝ｄ・TP≧｜TP-1−TP
｜）場合に、記憶部７に記憶している測定値と今
回の測定値とから平均時間間隔を演算し、単位時
間当り流量を演算する。 Next, calculate the absolute value |T P-1 −T P | of the difference between the latest measured value of the past stored in the storage unit, that is, the previous measured value T P-1 and the current measured value T P .
Next, compare △T P = α・T P and the above |T P-1 −T P |, and if △T P ≧ |T P-1 −T P |, it is assumed that there is no change and the An average value P is calculated from a predetermined number of stored past measured values and the current measured value.
For example, to find the measurement value from the time before the previous time, the previous time, and this time (i.e., the average of the three measurements), (T P-2 + T P-1 +
Calculate as T P )/3=T P. Next, from the average time interval P obtained in this way and the unit metering volume F u of the meter, the flow q per unit time is calculated by F u /T P , and the result is output as the flow rate q. What if△
If T P =d·T P <|T P-1 −T P |, it is determined that a flow rate change has occurred, and a change signal qc is outputted, and all data in the storage unit 7 is erased. In this way, the sum of the number of times the measured value stored in the storage unit 7 and the current measured value reaches a predetermined number (for example, 3
times), the previous measured value and the current measured value satisfy the above relationship (△T P = d・T P ≧｜T P-1 −T P
|), the average time interval is calculated from the measured value stored in the storage unit 7 and the current measured value, and the flow rate per unit time is calculated.
次に、測定した時間間隔が所定の時間以上の場
合につき説明する。この場合も、上述の場合同様
に、まず一定の係数βを測定値に乗ずる。この場
合のβは、係数αと同一であつてもよいし、また
長時間測定となるので、大きな値であつてもよ
い。次に、前回測定値TP-1と今回測定値TPの差
の絶対値を先に計算したβ・TPと比較し、β・
TP≧｜TP-1−TP｜となれば、今回の測定値TP
と、単位計量体積Fuにより、Fu／TPの演算によ
り単位時間当り流量ｑを出力する。次にβ・TP
＜｜TP-1−TP｜であれば、変化有信号qcを出力
し、記憶部７の記憶内容を消去し、今回測定値を
前回測定値として記憶部７に記憶し、次回の測定
演算に備える。このようにして記憶部７に記憶し
ている前記測定値TP-1と今回測定値TPとがβ・
TP≧｜TP-1−TP｜を満足すると上述したように、
Fu／TPを演算し、単位時間当り流量ｑを出す。
上述の例では、今回測定結果TPより流量ｑ演算
したが、前回測定値TP-1と今回測定値TPとの平
均値TP＝（TP-1＋TP）／２より流量ｑを演算して
もよい。 Next, a case in which the measured time interval is longer than a predetermined time will be explained. In this case, as in the case described above, the measured value is first multiplied by a constant coefficient β. In this case, β may be the same as the coefficient α, or may be a large value since the measurement is for a long time. Next, compare the absolute value of the difference between the previous measurement value T P-1 and the current measurement value T P with the previously calculated β・T P , and
If T P ≧｜T P-1 −T P ｜, then the current measured value T P
Then, the flow rate q per unit time is outputted by calculating F u /T P using the unit measured volume F u . Next, β・T P
If <|T P-1 −T P |, output the change signal qc, erase the memory contents of the storage unit 7, store the current measurement value in the storage unit 7 as the previous measurement value, and start the next measurement. Prepare for calculation. In this way, the measured value T P-1 stored in the storage unit 7 and the current measured value T P are β・
As mentioned above, if T P ≧ |T P-1 −T P | is satisfied,
Calculate F u /T P and obtain the flow rate q per unit time.
In the above example, the flow rate q is calculated from the current measurement result T P , but the flow rate q is calculated from the average value T P = (T P-1 + T P )/2 of the previous measurement value T P -1 and the current measurement value T P may be calculated.
次に、流量パルスの時間間隔が極めて長く、す
なわち流量が極めて少くなり、或いはゼロとなつ
た場合、すなわちタイマ５で計測している時間間
隔が第２の所定時間よりも長くなつたときは、演
算処理部６は、流量ゼロとしてゼロ流量をｑとし
て出力し、記憶部７の記憶内容を全て消去し、次
の流量パルスがタイマ５に入力されるのを待機す
る。 Next, when the time interval of the flow rate pulses is extremely long, that is, the flow rate becomes extremely low or zero, that is, when the time interval measured by the timer 5 becomes longer than the second predetermined time, The arithmetic processing unit 6 outputs the zero flow rate as q, erases all the stored contents of the storage unit 7, and waits for the next flow rate pulse to be input to the timer 5.
上述した実施例では、流量パルスの時間間隔に
基づいて単位時間当り流量を測定したが、所定時
間内の流量パルス数に基づくもの等、いずれの手
段であつてもよい。また記憶部には、流量パルス
の時間間隔の測定値を記憶させ、時間間隔の測定
値の処理をまず行なうが、時間間隔から直ちに単
位時間当りの流量を求め、その単位時間当り流量
において前回流量との比較等の処理を施しても同
一の効果が得られる。 In the embodiments described above, the flow rate per unit time is measured based on the time interval of the flow rate pulses, but any method may be used, such as one based on the number of flow rate pulses within a predetermined time. In addition, the storage unit stores the measured value of the time interval of the flow rate pulse, and the measured value of the time interval is first processed, but the flow rate per unit time is immediately calculated from the time interval, and the previous flow rate is calculated based on the flow rate per unit time. The same effect can be obtained even if processing such as comparison with is performed.
このように本実施例によれば、流量パルス間隔
が所定時間内の場合は過去の所定数の測定結果と
の平均を求め、この平均値より単位時間当り流量
を演算し、流量パルス間隔が所定時間以上であれ
ば、今回の測定時間間隔からまたは今回と前回の
測定時間間隔の平均値から単位時間当りの流量を
演算するものであり、流量パルスと測定時間が完
全に同期状態となり、非同期測定の如き誤差が発
生せず正確に単位時間当り流量が測定できる。ま
た所定時間以上の流量パルス間隔となるような低
流量でも測定できる。また大流量になるほど流量
パルスの時間間隔が短くなり、従つて計測時間が
短くなる、流量変化が発生した場合、流量変化後
ほぼ一定の流量となつた時点で変化後の流量を測
定するので、正確に変化後の流量を測定できると
いう効果を有する。 As described above, according to this embodiment, when the flow rate pulse interval is within a predetermined time, the average of a predetermined number of past measurement results is calculated, and the flow rate per unit time is calculated from this average value. If it is more than 1 hour, the flow rate per unit time is calculated from the current measurement time interval or from the average value of the current and previous measurement time intervals, and the flow rate pulse and measurement time are completely synchronized, resulting in asynchronous measurement. Flow rate per unit time can be measured accurately without errors such as. Furthermore, it is possible to measure even a low flow rate with a flow rate pulse interval of a predetermined time or longer. In addition, as the flow rate increases, the time interval between flow rate pulses becomes shorter, and therefore the measurement time becomes shorter.When a flow rate change occurs, the flow rate after the change is measured when the flow rate becomes almost constant after the change in flow rate. This has the effect of accurately measuring the flow rate after the change.
発明の効果
以上のように本発明によれば、流体の流量測定
装置において、流量が変化した後の流量を正確に
測定できるものである。Effects of the Invention As described above, according to the present invention, a fluid flow rate measuring device can accurately measure the flow rate after the flow rate has changed.
図は本発明の一実施例の流量測定装置の概略構
成図である。
１……流量センサ、４……演算処理装置、７…
…記憶部。
The figure is a schematic configuration diagram of a flow rate measuring device according to an embodiment of the present invention. 1...Flow rate sensor, 4...Arithmetic processing unit, 7...
...Memory Department.
Claims (1)
を計量するつど流量パルスを発信する流量センサ
と、前記流量パルスを入力とし、この流量パルス
に基づき単位時間当りの流量を演算する演算処理
装置とを備え、前記演算処理装置は、少くとも前
回の測定値を記憶する記憶部と、今回の測定値に
所定の係数を乗ずる演算手段と、その結果と、前
記記憶部に記憶している前回測定値と今回の測定
値との差の絶対値とを比較する比較手段と、前記
今回測定値に所定の係数を乗じた演算結果が前記
差の絶対値よりも大きいときに、今回測定値と記
憶部に記憶されている測定値とより単位時間当り
の流量を演算し、前記今回測定値に所定の係数を
乗じた演算結果が前記差の絶対値よりも小さい時
に前記記憶部に記憶されている測定値を消去する
流量演算手段を備える構成とした流量測定装置。1. A flow rate sensor installed in a fluid supply line that emits a flow rate pulse each time a unit measurement volume is measured, and an arithmetic processing device that takes the flow rate pulse as input and calculates the flow rate per unit time based on this flow rate pulse. The arithmetic processing device includes a storage unit that stores at least a previous measurement value, an arithmetic unit that multiplies the current measurement value by a predetermined coefficient, the result, and a previous measurement value that is stored in the storage unit. and a comparison means for comparing the absolute value of the difference between the current measured value and the current measured value; The flow rate per unit time is calculated from the measured value stored in the storage unit, and the current measured value is multiplied by a predetermined coefficient. When the calculation result is smaller than the absolute value of the difference, the measurement is stored in the storage unit. A flow rate measuring device configured to include a flow rate calculation means for erasing a value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11372283A JPS604818A (en) | 1983-06-23 | 1983-06-23 | Flow rate measuring apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11372283A JPS604818A (en) | 1983-06-23 | 1983-06-23 | Flow rate measuring apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS604818A JPS604818A (en) | 1985-01-11 |
| JPH0472177B2 true JPH0472177B2 (en) | 1992-11-17 |
Family
ID=14619479
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11372283A Granted JPS604818A (en) | 1983-06-23 | 1983-06-23 | Flow rate measuring apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS604818A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6122210A (en) * | 1984-07-10 | 1986-01-30 | Noritsu Co Ltd | Flow rate detector |
| JPH07111360B2 (en) * | 1988-05-10 | 1995-11-29 | トキコ株式会社 | Turbine flow meter correction circuit |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54108654A (en) * | 1978-02-14 | 1979-08-25 | Toyo Kogyo Co | Degital type fuel residue display system |
-
1983
- 1983-06-23 JP JP11372283A patent/JPS604818A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54108654A (en) * | 1978-02-14 | 1979-08-25 | Toyo Kogyo Co | Degital type fuel residue display system |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS604818A (en) | 1985-01-11 |
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