JP7246021B2 - ultrasonic flow meter - Google Patents

ultrasonic flow meter Download PDF

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JP7246021B2
JP7246021B2 JP2019082373A JP2019082373A JP7246021B2 JP 7246021 B2 JP7246021 B2 JP 7246021B2 JP 2019082373 A JP2019082373 A JP 2019082373A JP 2019082373 A JP2019082373 A JP 2019082373A JP 7246021 B2 JP7246021 B2 JP 7246021B2
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ultrasonic
propagation time
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delay time
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弘 中井
憲司 安田
康雄 木場
祐大 石崎
貴士 萱場
裕史 藤井
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Panasonic Intellectual Property Management Co Ltd
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本発明は、一対の送受信可能な超音波振動子を用いて超音波の伝搬時間を測定し、被測定流体の流量を計測する超音波流量計に関するものである。 The present invention relates to an ultrasonic flowmeter that measures the propagation time of ultrasonic waves using a pair of ultrasonic transducers that can transmit and receive, and measures the flow rate of a fluid to be measured.

従来の超音波流量計に用いられている超音波伝搬時間の測定方法は、一対の送受信可能な超音波振動子を対向して配置し、一方の超音波振動子をバースト信号で駆動し、超音波を送信し、他方の超音波振動子で受信して測定していた。図3は、伝搬時間の測定方法を説明する為の受信波形のイメージ図で、横軸に時間を、縦軸に電圧を示す。図中の起点T0は駆動波13の開始時点を、終点T1は駆動開始後、第m(図ではm=3)波終了時点を示す。R0は受信開始時点を、終点R1は受信開始後、第m波終了時点を示す。 The ultrasonic propagation time measurement method used in conventional ultrasonic flowmeters is to arrange a pair of ultrasonic transducers capable of transmitting and receiving to face each other, drive one of the ultrasonic transducers with a burst signal, and A sound wave was transmitted and received by the other ultrasonic transducer for measurement. FIG. 3 is an image diagram of a received waveform for explaining the method of measuring the propagation time, in which the horizontal axis indicates time and the vertical axis indicates voltage. The start point T0 in the figure indicates the start point of the driving wave 13, and the end point T1 indicates the end point of the m-th (m=3 in the figure) wave after the start of driving. R0 indicates the start point of reception, and R1 indicates the end point of the m-th wave after the start of reception.

このように、駆動波13の第m波目のゼロクロス点を終点T1とし、他方の超音波送受信器で受信した受信波14の第m波目のゼロクロス点を終点R1として、終点T1と終点R1との間の時間を超音波の伝搬時間TP1として測定し、この伝搬時間を用いて流体の流速を計測し、流量を演算していた(例えば、特許文献1参照)。 In this way, the zero-crossing point of the m-th wave of the driving wave 13 is defined as the end point T1, and the zero-crossing point of the m-th wave of the received wave 14 received by the other ultrasonic transmitter/receiver is defined as the end point R1. is measured as the propagation time TP1 of the ultrasonic wave, the flow velocity of the fluid is measured using this propagation time, and the flow rate is calculated (see, for example, Patent Document 1).

図4は特許文献2に記載された超音波流量計の構成を示すものである。この超音波流量計100は流体の流れる測定流路101に設置した超音波振動子102と、超音波振動子102を駆動する駆動回路103と、駆動回路103にスタート信号を出力する制御部104と、超音波の伝搬時間を測定する伝搬時間測定部105と、超音波振動子102から送信した超音波を受ける超音波振動子107と、超音波振動子107の出力を増幅するアンプ106と、アンプ106の出力と検知基準電圧15とを比較し大小関係が反転したときに伝搬時間測定部105を停止させる受信検知回路108から構成されている。 FIG. 4 shows the configuration of the ultrasonic flowmeter described in Patent Document 2. As shown in FIG. This ultrasonic flowmeter 100 includes an ultrasonic transducer 102 installed in a measurement channel 101 through which a fluid flows, a drive circuit 103 for driving the ultrasonic transducer 102, and a control unit 104 for outputting a start signal to the drive circuit 103. , a propagation time measurement unit 105 for measuring the propagation time of ultrasonic waves, an ultrasonic transducer 107 for receiving ultrasonic waves transmitted from the ultrasonic transducer 102, an amplifier 106 for amplifying the output of the ultrasonic transducer 107, an amplifier 106 is compared with the detection reference voltage 15, and the reception detection circuit 108 stops the propagation time measurement unit 105 when the magnitude relationship is reversed.

また、音速に対する温度の影響を無視できるように伝搬時間逆数差法を用いるために、測定流路101の上流側から下流側への超音波の伝搬時間と下流側から上流側への伝搬時間が測定できるように、切り替えスイッチ109を備えている。 In addition, in order to use the propagation time reciprocal difference method so that the effect of temperature on the speed of sound can be ignored, the propagation time of the ultrasonic wave from the upstream side to the downstream side of the measurement channel 101 and the propagation time from the downstream side to the upstream side are A changeover switch 109 is provided for measurement.

さらに、超音波振動子のバラツキや温度変化等によって超音波振動子内の遅れ時間や受信波形の変化による遅れ時間が変化した場合でも、超音波の伝搬時間が正確に測定できるように、送信側の超音波振動子から超音波を送信して1回目の受信波(第1受信波)の第m波目を受信検知回路で受信するまでの伝搬時間TPと、受信側の超音波振動子と送信側の超音波振動子に1回づつ反射して受信側の超音波振動子に達した2回目の受信波(第2受信波)の第m波目を受信検知回路で受信するまでの伝搬時間TP2を測定し、伝搬時間TPと第2伝搬時間TP2の差の2分の1より超音波振動子間の真の伝搬時間TP0と真の受信遅れ時間TRを求める受信遅れ時間測定手段110を備えたている。 Furthermore, even if the delay time inside the ultrasonic transducer or the delay time due to changes in the received waveform changes due to fluctuations in the ultrasonic transducer or temperature changes, etc., it is possible to accurately measure the propagation time of the ultrasonic waves. Propagation time TP from transmitting ultrasonic waves from the ultrasonic transducer to receiving the m-th wave of the first received wave (first received wave) by the reception detection circuit, and the ultrasonic transducer on the receiving side Propagation until the reception detection circuit receives the m-th wave of the second received wave (second received wave) that is reflected once by the ultrasonic transducer on the transmitting side and reaches the ultrasonic transducer on the receiving side A reception delay time measuring means 110 for measuring the time TP2 and obtaining the true propagation time TP0 between ultrasonic transducers and the true reception delay time TR from half the difference between the propagation time TP and the second propagation time TP2. are ready.

図5に第1受信波と第2受信波のイメージ図を示す。図に示すように、送信側の超音波振動子は、駆動波13で駆動されて超音波信号を送信し、受信側の超音波振動子は第1受信波14として受信する。同時に、反射波が発生して送信側の超音波振動子に波形21として到達して反射される。そして、この反射波を受信側の超音波振動子が第2受信波22として受信する。ここで、TRが測定した伝搬時間の遅れ時間である(例えば、特許文献2参照)。 FIG. 5 shows an image diagram of the first received wave and the second received wave. As shown in the figure, the ultrasonic transducer on the transmitting side is driven by the driving wave 13 to transmit an ultrasonic signal, and the ultrasonic transducer on the receiving side receives the first received wave 14 . At the same time, a reflected wave is generated, reaches the ultrasonic transducer on the transmission side as a waveform 21, and is reflected. Then, the ultrasonic transducer on the receiving side receives this reflected wave as the second received wave 22 . Here, TR is the delay time of the measured propagation time (see Patent Document 2, for example).

特開平9-33308号公報JP-A-9-33308 特開2005-172556号公報JP-A-2005-172556

しかしながら、特許文献2に記載された超音波流量計によると真の受信遅れ時間の測定が可能となり高精度の流量計測が行えるが、2回目の受信波を測定するためには通常の3倍の長さの伝搬時間を測定する必要があり、伝搬時間測定部を長く動作させるために、消費電流が非常に多くなるという課題があった。 However, according to the ultrasonic flowmeter described in Patent Document 2, it is possible to measure the true reception delay time and perform highly accurate flow measurement, but in order to measure the second received wave, it takes three times as much as usual. Since it is necessary to measure the length of the propagation time, and the propagation time measuring unit is operated for a long time, there is a problem that the current consumption becomes very large.

本発明は、前記従来の課題を解決するもので、2回目の受信波を測定する回数を大幅に減らしても、計測精度を劣化させることなく超音波流量計の消費電流を削減できる超音波流量計を提供することを目的とする。 The present invention solves the above-mentioned conventional problems, and even if the number of times of measuring the second received wave is greatly reduced, the ultrasonic flow rate that can reduce the current consumption of the ultrasonic flow meter without degrading the measurement accuracy. The purpose is to provide

前記従来の課題を解決するために、本発明の超音波流量計は、超音波信号を送受信可能な一対の超音波振動子と、一方の前記超音波振動子から送信され、流体を伝搬した超音波信号を他方の前記超音波振動子が受信するまでの超音波の伝搬時間を測定する伝搬時間測定部と、受信側の前記超音波振動子が受信した受信波の第m波目を検知する受信検知回路と、送信側の超音波振動子から超音波を送信して1回目の受信波の第m波目を前記受信検知回路で検知するまでの第1伝搬時間TPと、受信側の超音波振動子と送信側の超音波振動子で1回づつ反射して受信側の超音波振動子に達した2回目の受信波の第m波目を前記受信検知回路で検知するまでの第2伝搬時間TP2を測定し、前記第1伝搬時間TPと前記第2伝搬時間TP2の差の2分の1より前記超音波振動子間の真の伝搬時間TP0を求め、この真の伝搬時間TP0と前記第1伝搬時間TPの差より受信側の前記超音波振動子に超音波が到達して受信検知回路で受信開始から超音波の受信波の第m波目を受信したと検知するまでの受信遅れ時間TRを算出する受信遅れ時間測定手段と、前記受信遅れ時間測定手段による前記受信遅れ時間TRの測定を所定のタイミングで行って保存し更新する伝搬時間補正値保存手段と、前記受信遅れ時間TRを用いて前記伝搬時間測定部で測定した前記第1伝搬時間TPから前記受信遅れ時間TRを引いて補正伝搬時間TPCを求める伝搬時間補正手段と、前記補正伝搬時間TC又は前記真の伝搬時間TP0から演算によって前記超音波振動子間を満たす流体の流量を求める制御部と、を備えたことを特徴としたものである。 In order to solve the above-described conventional problems, the ultrasonic flowmeter of the present invention includes a pair of ultrasonic transducers capable of transmitting and receiving ultrasonic signals, and an ultrasonic transducer transmitted from one of the ultrasonic transducers and propagating through a fluid. A propagation time measuring unit for measuring the propagation time of the ultrasonic wave until the other ultrasonic transducer receives the sound wave signal, and the m-th wave of the received wave received by the ultrasonic transducer on the receiving side is detected. a reception detection circuit, a first propagation time TP from when an ultrasonic wave is transmitted from an ultrasonic transducer on the transmission side until the m-th wave of the first received wave is detected by the reception detection circuit; The second reception until the reception detection circuit detects the m-th wave of the second reception wave that is reflected once by the ultrasonic transducer and the ultrasonic transducer on the transmission side and reaches the ultrasonic transducer on the reception side. The propagation time TP2 is measured, the true propagation time TP0 between the ultrasonic transducers is obtained from half the difference between the first propagation time TP and the second propagation time TP2, and this true propagation time TP0 and From the difference of the first propagation time TP, the ultrasonic wave reaches the ultrasonic transducer on the receiving side and the reception detection circuit detects that the m-th wave of the received ultrasonic wave has been received from the start of reception. a reception delay time measuring means for calculating a delay time TR; a propagation time correction value storage means for measuring the reception delay time TR by the reception delay time measuring means at a predetermined timing and storing and updating the reception delay time; a propagation time correcting means for obtaining a corrected propagation time TPC by subtracting the reception delay time TR from the first propagation time TP measured by the propagation time measuring unit using TR; and the corrected propagation time TC or the true propagation time. and a control unit for determining the flow rate of the fluid that fills the space between the ultrasonic transducers by calculation from TP0.

これによって、2回目の受信波を測定する回数を大幅に減らしても、計測精度を劣化させることなく超音波流量計の消費電流を削減できる。 As a result, even if the number of times of measuring the second received wave is greatly reduced, the current consumption of the ultrasonic flowmeter can be reduced without degrading the measurement accuracy.

本発明の超音波流量計は、計測精度を劣化させることなく消費電流を削減できるため、超音波流量計に搭載する電池を少なくすることができ、超音波流量計の小型化とコストダウンが可能になる。 Since the ultrasonic flowmeter of the present invention can reduce current consumption without degrading measurement accuracy, it is possible to reduce the number of batteries installed in the ultrasonic flowmeter, and it is possible to reduce the size and cost of the ultrasonic flowmeter. become.

本発明の実施の形態1における超音波流量計の構成図FIG. 1 is a configuration diagram of an ultrasonic flowmeter according to Embodiment 1 of the present invention; 本発明の実施の形態2における超音波流量計の構成図Configuration diagram of an ultrasonic flowmeter according to Embodiment 2 of the present invention 超音波の伝搬時間の測定方法を説明する為の受信波形のイメージ図Image diagram of the received waveform for explaining the method of measuring the propagation time of ultrasonic waves 従来例の超音波流量計の構成図Configuration diagram of a conventional ultrasonic flowmeter 第1受信波、第2受信波を含む受信波形のイメージ図Image diagram of received waveform including first received wave and second received wave

第1の発明は、超音波信号を送受信可能な一対の超音波振動子と、一方の前記超音波振動子から送信され、流体を伝搬した超音波信号を他方の前記超音波振動子が受信するまでの超音波の伝搬時間を測定する伝搬時間測定部と、受信側の前記超音波振動子が受信した受信波の第m波目を検知する受信検知回路と、送信側の超音波振動子から超音波を送信して1回目の受信波の第m波目を前記受信検知回路で検知するまでの第1伝搬時間TPと、受信側の超音波振動子と送信側の超音波振動子で1回づつ反射して受信側の超音波振動子に達した2回目の受信波の第m波目を前記受信検知回路で検知するまでの第2伝搬時間TP2を測定し、前記第1伝搬時間TPと前記第2伝搬時間TP2の差の2分の1より前記超音波振動子間の真の伝搬時間TP0を求め、この真の伝搬時間TP0と前記第1伝搬時間TPの差より受信側の前記超音波振動子に超音波が到達して受信検知回路で受信開始から超音波の受信波の第m波目を受信したと検知するまでの受信遅れ時間TRを算出する受信遅れ時間測定手段と、前記受信遅れ時間測定手段による前記受信遅れ時間TRの測定を所定のタイミングで行って保存し更新する伝搬時間補正値保存手段と、前記受信遅れ時間TRを用いて前記伝搬時間測定部で測定した前記第1伝搬時間TPから前記受信遅れ時間TRを引いて補正伝搬時間TPCを求める伝搬時間補正手段と、前記補正伝搬時間TC又は前記真の伝搬時間TP0から演算によって前記超音波振動子間を満たす流体の流量を求める制御部と、を備えたことによって、2回目の受信波を測定する回数を大幅に減らすことが可能になり、計測精度を劣化させることなく超音波流量計の消費電流を削減できる。 A first invention is a pair of ultrasonic transducers capable of transmitting and receiving ultrasonic signals, and one of the ultrasonic transducers transmits the ultrasonic signal and propagates through a fluid, and the other ultrasonic transducer receives the ultrasonic signal. a propagation time measuring unit for measuring the propagation time of the ultrasonic wave to, a reception detection circuit for detecting the m-th wave of the received wave received by the ultrasonic transducer on the receiving side, and from the ultrasonic transducer on the transmitting side A first propagation time TP from when an ultrasonic wave is transmitted until the m-th wave of the first received wave is detected by the reception detection circuit, and the ultrasonic transducer on the receiving side and the ultrasonic transducer on the transmitting side are 1. A second propagation time TP2 until the reception detecting circuit detects the m-th wave of the second reception wave that has been reflected one by one and reaches the ultrasonic transducer on the receiving side is measured, and the first propagation time TP2 is measured. and the second propagation time TP2, the true propagation time TP0 between the ultrasonic transducers is obtained. From the difference between the true propagation time TP0 and the first propagation time TP, the a reception delay time measuring means for calculating a reception delay time TR from when the ultrasonic wave reaches the ultrasonic transducer and when the reception detecting circuit detects that the m-th wave of the received ultrasonic wave has been received; a propagation time correction value storing means for storing and updating the reception delay time TR measured by the reception delay time measuring means at a predetermined timing; a propagation time correcting means for obtaining a corrected propagation time TPC by subtracting the reception delay time TR from the first propagation time TP; and a fluid filling between the ultrasonic transducers by calculation from the corrected propagation time TC or the true propagation time TPO By providing a control unit that obtains the flow rate of , it is possible to greatly reduce the number of times the second received wave is measured, and the current consumption of the ultrasonic flowmeter can be reduced without degrading the measurement accuracy. .

第2の発明は、第1の発明の構成に加えて、前記伝搬時間補正値保存手段は、一定間隔のタイミングで前記受信遅れ時間測定手段を用いた前記受信遅れ時間TRの測定を行い、保存されている前記受信遅れ時間TRを更新するものである。 In a second invention, in addition to the configuration of the first invention, the propagation time correction value storage means measures and stores the reception delay time TR using the reception delay time measurement means at regular intervals. It updates the received reception delay time TR.

第3の発明は、第1の発明の構成に加えて、被測定流体の温度を測定するための温度センサと、前記温度センサで測定した流体の温度と前記第1伝搬時間TPと超音波の受信信号を所定の振幅に増幅する増幅率のいずれかが所定の値以上変化した場合に受信遅れ時間TRを更新するタイミングと判定する受信遅れ時間測定タイミング決定手段とを備え、前記伝搬時間補正値保存手段は、前記受信遅れ時間測定タイミング決定手段で受信遅れ時間TRを更新するタイミングと判定されたら、前記受信遅れ時間測定手段を用いて前記受信遅れ時間TRを測定し、保存されている前記受信遅れ時間TRを更新することによって、前記受信遅れ時間補正値が変化するタイミングで適格に受信遅れ時間を再測定することができるため、計測精度を劣化させずに超音波流量計の消費電流を削減できる。 A third invention, in addition to the configuration of the first invention, further includes a temperature sensor for measuring the temperature of the fluid to be measured, the temperature of the fluid measured by the temperature sensor, the first propagation time TP, and the ultrasonic waves. reception delay time measurement timing determining means for determining timing for updating the reception delay time TR when any of the amplification factors for amplifying the received signal to a predetermined amplitude changes by a predetermined value or more; and the propagation time correction value The storage means measures the reception delay time TR using the reception delay time measurement means when the reception delay time measurement timing determination means determines that it is time to update the reception delay time TR, and stores the stored reception delay time TR. By updating the delay time TR, the reception delay time can be properly remeasured at the timing when the reception delay time correction value changes, so the current consumption of the ultrasonic flowmeter can be reduced without degrading the measurement accuracy. can.

以下、本発明の実施の形態について、図面を参照しながら説明する。なお、この実施の形態によって本発明が限定されるものではない。 BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the present invention is not limited by this embodiment.

(実施の形態1)
以下、本発明の実施の形態1について、図1、図3、図5を用いて説明する。
(Embodiment 1)
Embodiment 1 of the present invention will be described below with reference to FIGS. 1, 3, and 5. FIG.

図1は、本発明の実施の形態1における超音波流量計の構成図を示すものである。図1に示すように、本実施の形態の超音波流量計20は、流体の流れる測定流路1の上流と下流に設置した一対の超音波振動子2、7と、一対の超音波振動子2、7の送受信の設定切り替えを行う切り替えスイッチ9と、送信側に設定された超音波振動子を駆動する駆動回路3と、駆動回路3にスタート信号を出力する制御部4と、超音波の伝搬時間を測定する伝搬時間測定部5と、受信側に設定された超音波振動子で受信した超音波信号を所定の振幅に増幅するアンプ6と、アンプ6で増幅された受信波の第m波目を検知する受信検知回路8を備えている。なお、本実施の形態では、m=3としており、以下、第m波目を第3波目として説明する。 FIG. 1 shows a configuration diagram of an ultrasonic flowmeter according to Embodiment 1 of the present invention. As shown in FIG. 1, an ultrasonic flowmeter 20 of the present embodiment includes a pair of ultrasonic transducers 2 and 7 installed upstream and downstream of a measurement channel 1 in which a fluid flows, and a pair of ultrasonic transducers 2 and 7, a switch 9 for switching transmission/reception settings, a drive circuit 3 for driving the ultrasonic transducer set on the transmission side, a control unit 4 for outputting a start signal to the drive circuit 3, and an ultrasonic wave. A propagation time measuring unit 5 for measuring the propagation time, an amplifier 6 for amplifying the ultrasonic signal received by the ultrasonic transducer set on the receiving side to a predetermined amplitude, and the m-th of the received wave amplified by the amplifier 6. A reception detection circuit 8 for detecting waves is provided. In this embodiment, m=3, and the m-th wave will be described as the third wave hereinafter.

ここで、受信検知回路8は、予め設定された検知基準電圧15とアンプ6で増幅された
受信波を比較し、大小関係が反転したことで第3波目を検知(タイミングP)し、その後の最初のゼロクロス点である終点R1を受信タイミングとし、伝搬時間測定部5は、送信開始から受信タイミングまでの時間を伝搬時間として測定する構成である。
Here, the reception detection circuit 8 compares the preset detection reference voltage 15 with the received wave amplified by the amplifier 6, detects the third wave (timing P) when the magnitude relationship is inverted, and then detects the third wave. The end point R1, which is the first zero-crossing point of , is used as the reception timing, and the propagation time measurement unit 5 measures the time from the start of transmission to the reception timing as the propagation time.

また、伝搬時間測定部5は、送信側の超音波振動子から超音波を送信して1回目の受信波(第1受信波)の第3波目を受信検知回路8で検知するまでの第1伝搬時間TPと、受信側の超音波振動子と送信側の超音波振動子で1回づつ反射して受信側の超音波振動子に達した2回目の受信波(第2受信波)の第3波目を受信検知回路8で検知するまでの第2伝搬時間TP2を測定し、第1伝搬時間TPと第2伝搬時間TP2の差の2分の1より超音波振動子間の真の伝搬時間TP0を求め、この真の伝搬時間TP0と第1伝搬時間TPの差より受信側の超音波振動子に超音波が到達して受信検知回路で受信開始から超音波の受信波の第3波目を受信したと検知するまでの受信遅れ時間TRを算出する受信遅れ時間測定手段10と、受信遅れ時間測定手段10による受信遅れ時間TRの測定を所定のタイミングでのみ行って保存し更新する伝搬時間補正値保存手段12と、受信遅れ時間TRを用いて測定した第1伝搬時間TPから受信遅れ時間TRを引いて補正伝搬時間TPCを求める伝搬時間補正手段11とを備えている。 Also, the propagation time measuring unit 5 measures the time from when an ultrasonic wave is transmitted from the ultrasonic transducer on the transmitting side to when the reception detecting circuit 8 detects the third wave of the first received wave (first received wave). 1 propagation time TP and the second received wave (second received wave) reflected once by the ultrasonic transducer on the receiving side and the ultrasonic transducer on the transmitting side and reaching the ultrasonic transducer on the receiving side The second propagation time TP2 until the third wave is detected by the reception detection circuit 8 is measured, and the true difference between the ultrasonic transducers is calculated from half the difference between the first propagation time TP and the second propagation time TP2. The propagation time TP0 is obtained, and from the difference between the true propagation time TP0 and the first propagation time TP, the ultrasonic wave reaches the ultrasonic transducer on the receiving side, and the reception detection circuit detects the third ultrasonic wave from the start of reception. A reception delay time measuring means 10 for calculating a reception delay time TR until a wave is detected, and the reception delay time TR is measured by the reception delay time measuring means 10 only at a predetermined timing, stored, and updated. A propagation time correction value storage means 12 and a propagation time correction means 11 for obtaining a corrected propagation time TPC by subtracting the reception delay time TR from the first propagation time TP measured using the reception delay time TR.

そして、制御部4は、補正伝搬時間TC又は真の伝搬時間TP0から演算によって超音波振動子2,7間を満たす流体の流量を求める。 Then, the control unit 4 calculates the flow rate of the fluid that fills the space between the ultrasonic transducers 2 and 7 from the corrected propagation time TC or the true propagation time TP0.

本実施の形態1において、伝搬時間補正値保存手段12は、受信遅れ時間測定手段10をあらかじめ設定された時間間隔で動作させて、測定された受信遅れ時間TRを用いて、保存されている受信遅れ時間TRを更新することを特徴としている。 In Embodiment 1, the propagation time correction value storage means 12 operates the reception delay time measurement means 10 at preset time intervals, and uses the measured reception delay time TR to calculate the stored reception It is characterized by updating the delay time TR.

そして、通常の流量計測時(受信遅れ時間測定手段10による受信遅れ時間TRの算出を行わない時)には、伝搬時間補正値保存手段12に保存されている受信遅れ時間TRを用いて第1伝搬時間TPを補正して流量計算に使用する補正伝搬時間TPCをTPC=TP-TRで求めている。ここで、伝搬時間補正値保存手段12としては、EEPROMやマイコン内のRAMを使用して実現可能である。 During normal flow measurement (when the reception delay time TR is not calculated by the reception delay time measurement means 10), the reception delay time TR stored in the propagation time correction value storage means 12 is used to obtain the first The corrected propagation time TPC used for calculating the flow rate by correcting the propagation time TP is obtained by TPC=TP-TR. Here, the propagation time correction value storage means 12 can be implemented using an EEPROM or a RAM within a microcomputer.

なお、受信遅れ時間測定手段10による受信遅れ時間TRの算出を行なう場合は、第2伝搬時間TP2と第1伝搬時間TPから真の伝搬時間TP0を求めることができるので、流量計算には真の伝搬時間TP0を使用することもできる。 When the reception delay time TR is calculated by the reception delay time measuring means 10, the true propagation time TP0 can be obtained from the second propagation time TP2 and the first propagation time TP. A propagation time TP0 can also be used.

また、受信遅れ時間測定手段10を動作させる間隔としては、通常の使用環境での温度変化によって、受信遅れ時間TRの変化が流量計算に影響しない程度として1分から10分程度の所定のタイミングとすることが望ましい。通常、超音波流量計の計測間隔は数秒であるが、受信遅れ時間測定手段10を動作させるタイミングを数分の一定間隔にすることによって、大幅に消費電流を削減できる。また、受信遅れ時間TRの測定タイミングが減っても周囲環境で受信遅れ時間TRが変化しないレベルでの頻度で更新するために、計測精度の劣化には繋がらない。 Also, the interval at which the reception delay time measuring means 10 is operated is set to a predetermined timing of about 1 minute to 10 minutes so that the change in the reception delay time TR does not affect the flow rate calculation due to the temperature change in the normal use environment. is desirable. Normally, the measurement interval of the ultrasonic flow meter is several seconds, but by setting the operation timing of the reception delay time measuring means 10 to a constant interval of several minutes, the current consumption can be greatly reduced. Further, even if the measurement timing of the reception delay time TR decreases, the update is performed at a frequency at which the reception delay time TR does not change in the surrounding environment, so that the measurement accuracy is not deteriorated.

以上のように、受信遅れ時間測定手段10による受信遅れ時間TRの算出を所定のタイミング或いは一定間隔のタイミングで行うことで、2回目の受信波を測定する回数を大幅に減らすことが可能になり、計測精度を劣化させることなく超音波流量計の消費電流を削減できる。 As described above, the calculation of the reception delay time TR by the reception delay time measuring means 10 is performed at a predetermined timing or at constant intervals, thereby greatly reducing the number of times the second reception wave is measured. , the current consumption of the ultrasonic flowmeter can be reduced without degrading the measurement accuracy.

(実施の形態2)
図2は、本発明の実施の形態2における超音波流量計の構成図を示すものである。本実施の形態における超音波流量計30の基本的な構成、動作は実施の形態1と同じである。
実施の形態1との差異は、測定流路1内に温度センサ16を備え、被測定気体の温度を測定可能にしたことと、制御部4に受信遅れ時間測定タイミング決定手段17を備えたことである。
(Embodiment 2)
FIG. 2 shows a configuration diagram of an ultrasonic flowmeter according to Embodiment 2 of the present invention. The basic configuration and operation of the ultrasonic flowmeter 30 in this embodiment are the same as in the first embodiment.
The difference from the first embodiment is that a temperature sensor 16 is provided in the measurement channel 1 to enable measurement of the temperature of the gas to be measured, and that the controller 4 is provided with reception delay time measurement timing determination means 17. is.

受信遅れ時間測定タイミング決定手段17では、温度センサ16で測定した現在の温度と現在の第1伝搬時間TPと現在の受信検知回路8で設定されている受信信号を所定の振幅に増幅するためのアンプ6の増幅率が前回の受信遅れ時間TRを測定したタイミングのそれぞれの値と所定の値以上の差が無いかを判定し、流体の温度、第1伝搬時間TP、増幅率のいずれかが所定の値以上変化した場合に受信遅れ時間TRを更新するタイミングと判定する。 In the reception delay time measurement timing determination means 17, the current temperature measured by the temperature sensor 16, the current first propagation time TP, and the current reception signal set in the reception detection circuit 8 are amplified to a predetermined amplitude. It is determined whether or not the amplification factor of the amplifier 6 differs from each value at the timing at which the previous reception delay time TR is measured and a predetermined value or more. It is determined that it is time to update the reception delay time TR when it has changed by a predetermined value or more.

そして、前記伝搬時間補正値保存手段は、受信遅れ時間測定タイミング決定手段17で受信遅れ時間TRを更新するタイミングと判定され場合のみ受信遅れ時間測定手段10を動作させ、受信遅れ時間TRを測定し、伝搬時間補正値保存手段12に保存されている受信遅れ時間TRを更新する。 Then, the propagation time correction value storage means operates the reception delay time measurement means 10 only when the reception delay time measurement timing determination means 17 determines that it is time to update the reception delay time TR, and measures the reception delay time TR. , the reception delay time TR stored in the propagation time correction value storage means 12 is updated.

以上により、周囲環境の温度変化や被測定気体のガス種の変化があった場合のみ受信遅れ時間測定手段を動作させることになるため、2回目の受信波を測定する回数を実施の形態1以上に減らすことが可能になり、消費電流の更なる削減が可能になる。 As described above, the reception delay time measuring means is operated only when there is a change in the temperature of the surrounding environment or a change in the gas type of the gas to be measured. , and the current consumption can be further reduced.

なお、本実施の形態では、超音波の伝搬経路が測定流路1の流れ方向に一致するように上流と下流に一対の超音波振動子2,7を対向して配置した構成で説明したが、一対の超音波振動子2,7と超音波の伝搬経路はこれに限らず、(1)超音波の伝搬経路が測定流路1の流れ方向に対して斜めに横切るように上流と下流に一対の超音波振動子2,7を対向して配置したもの、(2)測定流路1の上流と下流の同一面に一対の超音波振動子2,7を配置し、超音波の伝搬経路が測定流路1の対向する面に1回反射するようにしたもの、(3)測定流路1の上流と下流の同一面に一対の超音波振動子2,7を配置し、超音波の伝搬経路が測定流路1の対向する面に2回反射するようにしたものなど、種々の形態を採用できる。 In this embodiment, a pair of ultrasonic transducers 2 and 7 are arranged facing each other upstream and downstream so that the propagation path of ultrasonic waves matches the flow direction of the measurement flow path 1. , the pair of ultrasonic transducers 2 and 7 and the propagation paths of the ultrasonic waves are not limited to the above. (2) A pair of ultrasonic transducers 2 and 7 are arranged on the same surface upstream and downstream of the measurement channel 1, and the ultrasonic wave propagation path (3) A pair of ultrasonic transducers 2 and 7 are arranged on the same surface upstream and downstream of the measurement flow channel 1, and the ultrasonic wave Various forms can be adopted, such as one in which the propagation path reflects twice on the opposite surfaces of the measurement channel 1 .

以上のように、本発明にかかる超音波流量計は、2回目の受信波を測定するタイミングを大幅に減らすことが可能になり、計測精度を劣化させることなく超音波流量計の消費電流を削減できるため、搭載する電池を削減し、小型で高精度な超音波流量計を実現することが可能となり、ガスメータ等の用途にも適用できる。 As described above, the ultrasonic flowmeter according to the present invention can greatly reduce the timing of measuring the second received wave, and reduce the current consumption of the ultrasonic flowmeter without degrading the measurement accuracy. Therefore, it is possible to reduce the number of batteries to be mounted, realize a small and highly accurate ultrasonic flowmeter, and apply it to applications such as gas meters.

1 測定流路
2、7 超音波振動子
3 駆動回路
4 制御部
5 伝搬時間測定部
6 アンプ
8 受信検知回路
9 切り替えスイッチ
10 受信遅れ時間測定手段
11 伝搬時間補正手段
12 伝搬時間補正値保存手段
16 温度センサ
17 受信遅れ時間測定タイミング決定手段
20、30 超音波流量計
1 measurement channel 2, 7 ultrasonic transducer 3 drive circuit 4 control unit 5 propagation time measurement unit 6 amplifier 8 reception detection circuit 9 switch 10 reception delay time measurement means 11 propagation time correction means 12 propagation time correction value storage means 16 Temperature sensor 17 Reception delay time measurement timing determining means 20, 30 Ultrasonic flow meter

Claims (3)

超音波信号を送受信可能な一対の超音波振動子と、
一方の前記超音波振動子から送信され、流体を伝搬した超音波信号を他方の前記超音波振動子が受信するまでの超音波の伝搬時間を測定する伝搬時間測定部と、
受信側の前記超音波振動子が受信した受信波の第m波目を検知する受信検知回路と、
送信側の超音波振動子から超音波を送信して1回目の受信波の第m波目を前記受信検知回路で検知するまでの第1伝搬時間TPと、受信側の超音波振動子と送信側の超音波振動子で1回づつ反射して受信側の超音波振動子に達した2回目の受信波の第m波目を前記受信検知回路で検知するまでの第2伝搬時間TP2を測定し、前記第1伝搬時間TPと前記第2伝搬時間TP2の差の2分の1より前記超音波振動子間の真の伝搬時間TP0を求め、この真の伝搬時間TP0と前記第1伝搬時間TPの差より受信側の前記超音波振動子に超音波が到達して受信検知回路で受信開始から超音波の受信波の第m波目を受信したと検知するまでの受信遅れ時間TRを算出する受信遅れ時間測定手段と、
前記受信遅れ時間測定手段による前記受信遅れ時間TRの測定を所定のタイミングで行って保存し更新する伝搬時間補正値保存手段と
記伝搬時間測定部で測定した前記第1伝搬時間TPから前記伝搬時間補正値保存手段に保存されている前記受信遅れ時間TRを引いて補正伝搬時間TPCを求める伝搬時間補正手段と、
前記補正伝搬時間TPC又は前記真の伝搬時間TP0から演算によって前記超音波振動子間を満たす流体の流量を求める制御部と、
を備えた超音波流量計。
a pair of ultrasonic transducers capable of transmitting and receiving ultrasonic signals;
a propagation time measuring unit that measures the propagation time of an ultrasonic wave until the other ultrasonic transducer receives an ultrasonic signal transmitted from one of the ultrasonic transducers and propagating through a fluid;
a reception detection circuit for detecting the m-th wave of the reception wave received by the ultrasonic transducer on the reception side;
A first propagation time TP from when an ultrasonic wave is transmitted from the ultrasonic transducer on the transmitting side until the m-th wave of the first received wave is detected by the reception detection circuit, and the ultrasonic transducer on the receiving side and transmission Measure the second propagation time TP2 until the reception detecting circuit detects the m-th wave of the second received wave that is reflected once by the ultrasonic transducer on the receiving side and reaches the ultrasonic transducer on the receiving side. Then, the true propagation time TP0 between the ultrasonic transducers is obtained from half the difference between the first propagation time TP and the second propagation time TP2, and this true propagation time TP0 and the first propagation time From the difference in TP, the reception delay time TR from when the ultrasonic wave reaches the ultrasonic transducer on the receiving side and when the reception detection circuit detects that the m-th wave of the received ultrasonic wave has been received is calculated. a reception delay time measuring means for
Propagation time correction value storage means for measuring the reception delay time TR by the reception delay time measuring means at a predetermined timing and storing and updating the correction value ;
a propagation time correction means for obtaining a corrected propagation time TPC by subtracting the reception delay time TR stored in the propagation time correction value storage means from the first propagation time TP measured by the propagation time measuring unit ;
a control unit that obtains a flow rate of the fluid that fills between the ultrasonic transducers by calculation from the corrected propagation time TPC or the true propagation time TP0;
Ultrasonic flow meter with
前記伝搬時間補正値保存手段は、一定間隔のタイミングで前記受信遅れ時間測定手段を用いた前記受信遅れ時間TRの測定を行い、保存されている前記受信遅れ時間TRを更新する請求項1に記載の超音波流量計。 2. The propagation time correction value storage means according to claim 1, wherein said reception delay time TR is measured using said reception delay time measuring means at regular intervals, and said stored reception delay time TR is updated. of ultrasonic flowmeters. 被測定流体の温度を測定するための温度センサと、
前記温度センサで測定した流体の温度と前記第1伝搬時間TPと超音波の受信信号を所定の振幅に増幅する増幅率のいずれかが所定の値以上変化した場合に受信遅れ時間TRを更新するタイミングと判定する受信遅れ時間測定タイミング決定手段とを備え、
前記伝搬時間補正値保存手段は、前記受信遅れ時間測定タイミング決定手段で受信遅れ時間TRを更新するタイミングと判定されたら、前記受信遅れ時間測定手段を用いて前記受信遅れ時間TRを測定し、保存されている前記受信遅れ時間TRを更新する請求項1に記載の超音波流量計。
a temperature sensor for measuring the temperature of the fluid to be measured;
The reception delay time TR is updated when any one of the temperature of the fluid measured by the temperature sensor, the first propagation time TP, and the amplification factor for amplifying the received ultrasonic signal to a predetermined amplitude changes by a predetermined value or more. Reception delay time measurement timing determination means for determining timing,
The propagation time correction value storage means measures and stores the reception delay time TR using the reception delay time measurement means when the reception delay time measurement timing determination means determines that it is time to update the reception delay time TR. 2. The ultrasonic flowmeter according to claim 1, wherein the received reception delay time TR is updated.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3419341B2 (en) 1999-04-02 2003-06-23 松下電器産業株式会社 Flow measurement device
JP3427762B2 (en) 1999-01-21 2003-07-22 松下電器産業株式会社 Ultrasonic flow meter
JP4561088B2 (en) 2003-12-10 2010-10-13 パナソニック株式会社 Ultrasonic flow meter
JP2011158470A (en) 2010-01-07 2011-08-18 Panasonic Corp Ultrasonic flowmeter
JP4792653B2 (en) 2001-04-20 2011-10-12 パナソニック株式会社 Flowmeter

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3427762B2 (en) 1999-01-21 2003-07-22 松下電器産業株式会社 Ultrasonic flow meter
JP3419341B2 (en) 1999-04-02 2003-06-23 松下電器産業株式会社 Flow measurement device
JP4792653B2 (en) 2001-04-20 2011-10-12 パナソニック株式会社 Flowmeter
JP4561088B2 (en) 2003-12-10 2010-10-13 パナソニック株式会社 Ultrasonic flow meter
JP2011158470A (en) 2010-01-07 2011-08-18 Panasonic Corp Ultrasonic flowmeter

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