JPH0472176B2 - - Google Patents
Info
- Publication number
- JPH0472176B2 JPH0472176B2 JP58113720A JP11372083A JPH0472176B2 JP H0472176 B2 JPH0472176 B2 JP H0472176B2 JP 58113720 A JP58113720 A JP 58113720A JP 11372083 A JP11372083 A JP 11372083A JP H0472176 B2 JPH0472176 B2 JP H0472176B2
- Authority
- JP
- Japan
- Prior art keywords
- flow rate
- time
- measurement
- pulse
- interval
- 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
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
Landscapes
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Volume Flow (AREA)
- Details Of Flowmeters (AREA)
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、流体の流量測定装置に関し、特にガ
ス事後防止装置等単位時間当りの流量の測定が必
要な装置に好適な流量測定装置に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a fluid flow rate measuring device, and particularly to a flow rate measuring device suitable for devices such as gas post-prevention devices that require measurement of flow rate per unit time.
従来例の構成とその問題点
従来の流量測定装置としては、流体としてのガ
スの供給ライン中に設けたガスメータと、ガスメ
ータ内の回転軸に永久磁石を円周の一部に取付け
た円盤を固定し、永久磁石の磁界を検出するホー
ルiCを設けて、円盤が一回転するごとに１パルス
の流量パルスを発信させ、この流量パルスの一分
間の数をカウンタでカウントし平均流量を計算す
る制御装置とで構成する。この装置では、所定時
間内の流量パルス数に基づいて平均流量を計算す
るが、所定時間内に流量変化が発生すれば、所定
時間内の流量パルス数が変化するとともに、その
計算結果としての平均流量は、変化前流量と変化
後流量の時間平均の流量となり、正確な流量が測
定できない。またその次の計測時にようやく正確
な変化後の流量が測定できるが、測定には所定の
時間を要するから、例えば測定開始直後に流量変
化があつた場合、所定時間の２倍（上例では所定
時間が１分だから２分）の時間が必要となる。Configuration of conventional examples and their problems Conventional flow rate measuring devices include a gas meter installed in the gas supply line as a fluid, and a disk with a permanent magnet attached to a part of the circumference fixed to the rotating shaft inside the gas meter. A Hall iC is installed to detect the magnetic field of the permanent magnet, and one flow pulse is emitted every time the disk rotates, and the number of flow pulses per minute is counted by a counter to calculate the average flow rate. It consists of a device. This device calculates the average flow rate based on the number of flow pulses within a predetermined time, but if a change in flow rate occurs within a predetermined time, the number of flow pulses within a predetermined time changes, and the average flow rate as a result of the calculation changes. The flow rate is the time average flow rate of the flow rate before the change and the flow rate after the change, and an accurate flow rate cannot be measured. In addition, the flow rate after the change can be accurately measured at the next measurement, but since the measurement requires a predetermined time, for example, if the flow rate changes immediately after the start of measurement, it will take twice the predetermined time (in the above example, the predetermined time). Since the time is 1 minute, it will take 2 minutes.
発明の目的
本発明は上記従来の欠点を解消するもので、測
定途中に流量変化があつた場合、変化後の流量を
迅速かつ正確に測定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 quickly and accurately measure the flow rate after the change when the flow rate changes during measurement.
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、所定の単位
計算体積を計算するつど流量パルスを発信する流
量センサからの流量パルスを演算処理装置に入力
し、演算処理装置内のクウンタにより流量パルス
をカウントし、演算処理部により所定時間毎の流
量パルス数に基づいて単位時間当り流量を演算す
るとともに、流量パルスの時間間隔をタイマで測
定し、記憶部に記憶している前回測定した時間間
隔と、今回測定した時間間隔とが所定の関係を満
足したとき、その回の流量測定を中止させ、次回
の流量測定を新たに開始させる構成であり、流量
測定中に流量変化が生じた場合、直ちにその回の
流量測定を中止し、次回の流量測定を新たに開始
するので、変化後の流量が迅速にかつ正確に測定
できる、流量変化の有無は流量パルスの時間間隔
により常に監視されているので、速かに流量の変
化を検出できる、測定開始直後に流量変化が発生
した場合にも、その回の流量測定を中止し新たに
次回の流量測定を開始させるので、所定時間が例
えば１分である場合、流量変化発生後約１分の後
には変化後の流量を正確に測定でき従来例の装置
よりも速く測定できるという効果を有するもので
ある。Structure of the Invention In order to achieve the above object, the flow rate measurement device of the present invention is provided in a fluid supply line and uses a flow rate pulse from a flow rate sensor that transmits a flow rate pulse each time a predetermined unit calculation volume is calculated to be processed by an arithmetic processing device. The counter in the arithmetic processing unit counts the flow rate pulses, and the arithmetic processing unit calculates the flow rate per unit time based on the number of flow rate pulses at each predetermined time, and also measures the time interval of the flow rate pulses with a timer. , when the time interval measured last time stored in the storage unit and the time interval measured this time satisfy a predetermined relationship, the current flow rate measurement is stopped and the next flow rate measurement is newly started. If a flow rate change occurs during flow rate measurement, the current flow rate measurement is immediately stopped and the next flow rate measurement is started anew, so the flow rate after the change can be measured quickly and accurately. Since the presence or absence is constantly monitored by the time interval of flow pulses, changes in flow rate can be detected quickly. Even if a change in flow rate occurs immediately after the start of measurement, the flow rate measurement for that time is stopped and the next one is restarted. Since the flow rate measurement is started, if the predetermined time is 1 minute, for example, the flow rate after the change can be accurately measured approximately 1 minute after the flow rate change occurs, which has the effect of being able to measure the flow rate faster than conventional devices. It is.
実施例の説明
以下本発明の一実施例について図面に基づいて
説明する。DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below based on the drawings.
第１図において、１はガス供給ライン、２はガ
ス供給ライン中に設けられた流量センサで、膜式
ガスメータ３、膜式ガスメータの計量応動部分の
例えば膜、膜の変位を伝達するリンク機構部等に
設けた磁石、磁石の磁界を検出する磁界センサと
してのリードスイツチ４より構成され、リードス
イツチはメータ３が単位計算体積を計量するつど
オフからオンとなる流量パウスを発信する。５は
流量パルスＦを入力とする演算処理装置で、以下
のように構成する。は流量パルスＦをカウントし
カウント数をFCとして出力するカウンタ、７は
タイマで、測定時間をＴとして出力する。８は演
算処理部で、流量パルスＦ、カウンタ出力FCタ
イマ出力Ｔ、９なる記憶部の出力としての前回測
定流量パルス時間間隔（以下前回間隔と略述）
T′および１０なる記憶部の積算時間間隔TAを入
力とし、カウンタ６をリセツトする信号CR、タ
イマ７をリセツトする信号TR、記憶部９の記憶
データとしての信号TP、記憶部１０の記憶デー
タとしてのTA′、単位時間当り流量演算結果の
Ｑ、変化有信号qcを出力とする。記憶部１０は、
測定開始後の積算測定時間を記憶している一種の
タイマとして動作する。なお演算処理部１０は、
タイマ７からの測定値と記憶部９の前回間隔を比
較し計測の中止等を判定する判定手段を備える。 In FIG. 1, 1 is a gas supply line, 2 is a flow rate sensor provided in the gas supply line, and is a membrane gas meter 3, a link mechanism that transmits the displacement of the metering response part of the membrane gas meter, such as a membrane, The reed switch 4 serves as a magnetic field sensor that detects the magnetic field of the magnet, etc., and the reed switch emits a flow rate that changes from off to on each time the meter 3 measures a unit calculation volume. Reference numeral 5 denotes an arithmetic processing unit which inputs the flow rate pulse F, and is configured as follows. 7 is a counter that counts the flow rate pulse F and outputs the count as FC, and 7 is a timer that outputs the measurement time as T. 8 is an arithmetic processing unit which outputs the flow rate pulse F, the counter output FC timer output T, and the previously measured flow rate pulse time interval (hereinafter abbreviated as the previous interval) as the output of the storage unit 9.
T' and the accumulated time interval TA of the storage section 10 are input, and the signal CR for resetting the counter 6, the signal TR for resetting the timer 7, the signal T P as the storage data of the storage section 9, and the storage data of the storage section 10 are input. The outputs are T A ' as , Q as the flow rate calculation result per unit time, and change signal qc. The storage unit 10 is
It operates as a type of timer that stores the cumulative measurement time after the start of measurement. Note that the arithmetic processing unit 10 is
A determining means is provided for comparing the measured value from the timer 7 and the previous interval stored in the storage section 9 to determine whether or not to stop the measurement.
以下上記構成における作用について、第２図の
動作説明用タイミング図を参照しつつ説明する。
第２図でイはガス供給ラインを流れている単位時
間当りの流量値、ロは流量パルスＦ、ハは測定に
当つての所定時間、ニは流量測定回、ホは演算処
理装置により出力される流量Ｑ、ヘは変化有信号
pcを示す。今一定流量Ｑ１が流れている状態で、
時刻toにてｉ回目の測定を開始したとする。この
ときのパルス間隔はＴ１であり、toより時間Ｔ１
の後に１発目の流量パルスＦが発信される。カウ
ンタ６はこれを１と計数し、演算処理部８は、タ
イマ７の出力Ｔ１を入力し、記憶部９の前回間隔
T′とを次のようにして比較する。まず今回測定
間隔Ｔ１に所定数αを乗ずる。このαは、一定流
量が流れている状態で発生する流量パルスの時間
間隔のばらつき等を考慮した許容変動巾であつ
て、例えば１％である。次に、前回間隔T′と今
回間隔の差の絶対値｜T′−T1｜を演算する。次
に先に演算したα・T1と｜T′−T1｜とを比較
し、α・T1≧｜T′−T1｜なら測定し続行し、
α・T1＜｜T′−T1｜ならこの回の測定を中止
し、前回間隔データとして今回間隔データＴ１を
記憶部９に出力し記憶部９の記憶データを変更し
次回の比較に備える。同時にタイマ７を信号TR
によりリセツトし、次の流量パルス（２発目の流
量パルス）までの時間を測定する。今まで一定量
流Ｑ１が流れ続けていたので１発目の流量パルス
までの時間間隔Ｔ１と、前回間隔T′とはα・T1
≧｜T′−T1｜を満足し、測定を続行する。演算
処理部８は時間間隔Ｔ１と記憶部１０に記憶され
ているこれまでの積算時間（上例ではゼロ）を加
え、結果を記憶部１０に記憶させる。時刻ｔ１で
所定の時間TMが経過したので、演算処理部８は、
カウンタ６の計数値FC（図の例では２）と、これ
まで積算した時間間隔TA（図の例では２Ｔ１）
とから、単位時間当り流量Ｑを、Ｑ＝Fu・Fc／
TAにより演算し出力する。ここでFuは、単位数
量体積を示い、ガスメータ３が例えばＮ型３号メ
ータであれば、0.9である。演算処理部８はそ
の次にカウンタ６を信号CRによりリセツトし記
憶部１０の記憶データをゼロとし次の測定（ｉ＋
１回目）に待機させる。時刻ｔ２で、流量がＱ１
よりＱ２に変化したとする。（ｉ＋１）回目の計
測中の１発目から２発目の重量パルスが入力され
る時刻ｔ３までの時間間隔はT2≠T1となり、
α・T2＜｜T1−T2｜を満足するので、演算処理
部８は流量測定を中止し、カウンタ６を信号CR
によりリセツトし、次の回すなわち（ｉ＋２）回
目の測定を新たにスタートさせるとともに流量変
化有信号qCを出力する。時刻ｔ３以降の流量は
Ｑ２と一定であるから、１発目の流量パルスが入
力される時刻＋４以降流量パルスの時間間隔はＴ
３となり略々一定となる。（ｉ＋２）回目の測定
で、１発目の流量パルスまでの時間間隔Ｔ３はＴ
２とは異なり、α・T3＜｜T2−T3｜を満足する
ので、（ｉ＋２）回目の測定を中止し、（ｉ＋３）
回目の測定を新たに開始する。量流Ｑ１を測定し
たｉ回目の流量測定と同様に、時刻ｔ５で所定の
時間TMが経過すると、カウンタ６の計数値FC
（図の例では３）、記憶部１０に記憶されている積
算間隔TA（図の例では約３．T3）と単位計量体
積Fuより、流量Q2をFu・Fc／TAにより演算し
出力するとともに、カウンタ６を信号によりリセ
ツトし、記憶部１０の内容をリセツトする。 The operation of the above structure will be explained below with reference to the timing chart for explaining the operation in FIG.
In Figure 2, A is the flow rate per unit time flowing through the gas supply line, B is the flow rate pulse F, C is the predetermined time for measurement, D is the number of flow rate measurements, and E is the value output by the arithmetic processing unit. Flow rate Q, F is a change signal
Shows pc. Now, with a constant flow rate Q1 flowing,
Assume that the i-th measurement is started at time to. The pulse interval at this time is T1, and the time T1 from to
After that, the first flow rate pulse F is transmitted. The counter 6 counts this as 1, and the arithmetic processing unit 8 inputs the output T1 of the timer 7 and stores the previous interval in the storage unit 9.
Compare with T′ as follows. First, the current measurement interval T1 is multiplied by a predetermined number α. This α is a permissible fluctuation range that takes into account variations in the time intervals of flow pulses that occur when a constant flow rate is flowing, and is, for example, 1%. Next, the absolute value |T'-T1| of the difference between the previous interval T' and the current interval is calculated. Next, compare α・T1 calculated earlier and |T′−T1|, and if α・T1≧|T′−T1|, measure and continue.
If α·T1<|T′−T1|, the current measurement is stopped, the current interval data T1 is output to the storage section 9 as the previous interval data, and the stored data in the storage section 9 is changed in preparation for the next comparison. At the same time, timer 7 is set to signal TR.
and measure the time until the next flow pulse (second flow pulse). Since a constant flow Q1 has been flowing until now, the time interval T1 until the first flow pulse and the previous interval T' are α・T1
≧｜T′−T1｜ is satisfied and the measurement is continued. The arithmetic processing unit 8 adds the time interval T1 and the accumulated time up to now stored in the storage unit 10 (zero in the above example), and stores the result in the storage unit 10. Since the predetermined time T M has passed at time t1, the arithmetic processing unit 8
Count value FC of counter 6 (2 in the example shown) and time interval TA accumulated so far (2T1 in the example shown)
From this, the flow rate Q per unit time is Q=Fu・Fc/
Calculate and output using TA. Here, Fu indicates unit quantity volume, and if the gas meter 3 is, for example, an N type No. 3 meter, it is 0.9. The arithmetic processing unit 8 then resets the counter 6 with the signal CR, sets the stored data in the storage unit 10 to zero, and starts the next measurement (i+
1st time). At time t2, the flow rate is Q1
Suppose that the situation changes to Q2. The time interval from the first weight pulse to the time t3 when the second weight pulse is input during the (i+1)th measurement is T2≠T1,
Since α・T 2 <|T 1 −T 2 | is satisfied, the arithmetic processing unit 8 stops flow rate measurement and outputs the counter 6 to the signal CR.
is reset, and the next measurement, that is, the (i+2)th measurement is started anew, and a flow rate change signal qC is output. Since the flow rate after time t3 is constant as Q2, the time interval between flow rate pulses after time +4 when the first flow pulse is input is T.
3, which is approximately constant. In the (i+2)th measurement, the time interval T3 until the first flow pulse is T
2, the (i + 2 )th measurement is canceled and the (i+ 3 )
Start a new measurement. Similarly to the i-th flow rate measurement in which the flow rate Q1 was measured, when the predetermined time T M has elapsed at time t5, the count value FC of the counter 6 is
(3 in the example in the figure), the flow rate Q 2 is calculated by Fu・Fc/TA from the integration interval TA (approximately 3.T 3 in the example in the figure) stored in the storage unit 10 and the unit measurement volume Fu and is output. At the same time, the counter 6 is reset by a signal, and the contents of the storage section 10 are reset.
このように本実施例によれば、流量変化が発生
すれば、前回の流量パルス間隔と今回のパルス間
隔とが所定の関係を万沿するか否かで判定してい
るので、直ちにこれを検出できる。また変化を検
出した時点でその回の測定を中止し、直ちに次の
測定を開始するので、変化後の流量を従来例より
は速く測定できるという効果を有する。 According to this embodiment, when a flow rate change occurs, it is determined whether the previous flow rate pulse interval and the current pulse interval match a predetermined relationship, so that this can be detected immediately. can. Furthermore, since the current measurement is stopped when a change is detected and the next measurement is immediately started, the flow rate after the change can be measured faster than in the conventional example.
なお上述した演算処理装置としては、例えばカ
ウンタやタイマを内蔵したマイクロコンピユータ
や、記憶部をRAMとして内蔵しているマイクロ
コンピユータを用いることができ、マイクコンピ
ユータを用いれば、容易にこの装置を実現でき
る。 Note that as the arithmetic processing device mentioned above, for example, a microcomputer with a built-in counter or timer, or a microcomputer with a built-in memory section as RAM can be used, and if a microphone computer is used, this device can be easily realized. .
発明の効果
以上のように本発明によれば次の効果を得るこ
とができる。Effects of the Invention As described above, according to the present invention, the following effects can be obtained.
(1) 流量変化が発生すれば、直ちにこの変化を検
出できる。(1) If a change in flow rate occurs, this change can be detected immediately.
(2) 変化後の流量をす速く測定できる。(2) The flow rate after change can be quickly measured.
(3) パルス間隔の変化が、一定流量時のばらつき
によるものなのか、真に流量が変化したものな
のかを判別でき、測定精度がよい。(3) It is possible to determine whether changes in pulse intervals are due to variations at a constant flow rate or true changes in flow rate, and the measurement accuracy is good.
第１図は本発明の一実施例である流量測定装置
の概略構成図、第２図は第１図の装置の動作説明
用タイミング図である。
１……流体供給ライン、２……流量センサ、５
……演算処理装置、６……カウンタ、７……タイ
マ、８……演算処理部、９……記憶部。
FIG. 1 is a schematic configuration diagram of a flow rate measuring device which is an embodiment of the present invention, and FIG. 2 is a timing chart for explaining the operation of the device shown in FIG. 1...Fluid supply line, 2...Flow rate sensor, 5
...Arithmetic processing unit, 6...Counter, 7...Timer, 8...Arithmetic processing section, 9...Storage section.
Claims (1)
量体積を計算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、所定時間
毎の流量パルス数に基づいて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、前記流量パルス数をカウントするカウン
タと、流量パルスの時間間隔を測定するタイマ
と、少くとも１回前に前記タイマにて測定した流
量パルスの時間間隔を前回間隔として記憶する記
憶部と、前記カウンタにてカウントする所定時間
毎の流量パルス数に基づき単位時間当り流量を演
算すると共に前記タイマにて今回測定した流量パ
ルス時間間隔と、前記記憶部に記憶されている前
回間隔とが所定の関係を満足したとき、今回の流
量の測定を中止し、新たに次回の流量の測定を開
始させる演算処理部からなる流量測定装置。1. A flow rate sensor that is installed in a fluid supply line and emits a flow rate pulse every time a predetermined unit measurement volume is calculated, and a flow rate sensor that uses the flow rate pulse as input and calculates the flow rate per unit time based on the number of flow pulses for each predetermined time. a calculation processing device that performs calculations; the calculation processing device includes a counter that counts the number of flow rate pulses, a timer that measures the time interval of the flow rate pulses, and a flow rate pulse that has been measured by the timer at least once before. a storage unit that stores the time interval of as the previous interval; a flow rate pulse time interval that calculates the flow rate per unit time based on the number of flow rate pulses counted by the counter at each predetermined time interval; and a flow rate pulse time interval that is currently measured by the timer; A flow rate measuring device comprising a calculation processing unit that stops measuring the current flow rate and starts a new measurement of the next flow rate when a predetermined relationship is satisfied with the previous interval stored in the storage unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58113720A JPS604816A (en) | 1983-06-23 | 1983-06-23 | flow measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58113720A JPS604816A (en) | 1983-06-23 | 1983-06-23 | flow measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS604816A JPS604816A (en) | 1985-01-11 |
| JPH0472176B2 true JPH0472176B2 (en) | 1992-11-17 |
Family
ID=14619430
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58113720A Granted JPS604816A (en) | 1983-06-23 | 1983-06-23 | flow measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS604816A (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5853723B2 (en) * | 1978-02-14 | 1983-12-01 | マツダ株式会社 | Automotive digital fuel level display device |
| JPS57520A (en) * | 1980-06-02 | 1982-01-05 | Ricoh Co Ltd | Electronic type flowmeter |
-
1983
- 1983-06-23 JP JP58113720A patent/JPS604816A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS604816A (en) | 1985-01-11 |
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