GB2267568A - Acoustic flowmeter - Google Patents

Acoustic flowmeter

Info

Publication number
GB2267568A
GB2267568A GB9314722A GB9314722A GB2267568A GB 2267568 A GB2267568 A GB 2267568A GB 9314722 A GB9314722 A GB 9314722A GB 9314722 A GB9314722 A GB 9314722A GB 2267568 A GB2267568 A GB 2267568A
Authority
GB
United Kingdom
Prior art keywords
signal
generate
signals
flow path
mixed
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
Application number
GB9314722A
Other versions
GB9314722D0 (en
GB2267568B (en
Inventor
Lawrence Anthony Jones
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Endress and Hauser Ltd
Original Assignee
Endress and Hauser Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Endress and Hauser Ltd filed Critical Endress and Hauser Ltd
Publication of GB9314722D0 publication Critical patent/GB9314722D0/en
Publication of GB2267568A publication Critical patent/GB2267568A/en
Application granted granted Critical
Publication of GB2267568B publication Critical patent/GB2267568B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/66—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
    • G01F1/667—Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters

Abstract

An acoustic flowmeter comprising an acoustic signal source, which launches a signal output into a flow path and detects the signal after transmission through the flow path. The time taken for the signal to be transmitted through the flow path is measured and the rate of flow within the flow is calculated from the measured transmission time. In order to improve the signal to noise ratio of the meter, acoustic signals transmitted through the flow path generate a first signal which is mixed with a second signal of different frequency to generate a third signal. The first signal is also mixed with a fourth signal to generate a fifth signal, the second and fourth signals being of the same frequency and in quadrature. The third and fifth signals are applied to a pair of low pass filters (79) having a cut-off frequency selected such that signals at a frequency substantially equal to or less than the difference in frequency between the first and second signals are passed. The filtered third signal is mixed with the second to generate a sixth signal, and the filtered fifth signal is mixed with the fourth signal to generate a seventh signal. The sixth and seventh signals are combined to generate an eighth signal which is representative of the signal transmitted through the flow path. The signal to noise ratio of the eighth signal is very much larger than the signal to noise ratio of the first signal as a result of rejection of unwanted signal components in the low pass filters. <IMAGE>
GB9314722A 1991-03-26 1993-07-16 Acoustic flowmeter Expired - Fee Related GB2267568B (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB919106465A GB9106465D0 (en) 1991-03-26 1991-03-26 Acoustic flowmeter
PCT/GB1992/000550 WO1992017753A1 (en) 1991-03-26 1992-03-25 Acoustic flowmeter

Publications (3)

Publication Number Publication Date
GB9314722D0 GB9314722D0 (en) 1993-09-29
GB2267568A true GB2267568A (en) 1993-12-08
GB2267568B GB2267568B (en) 1994-08-03

Family

ID=10692266

Family Applications (2)

Application Number Title Priority Date Filing Date
GB919106465A Pending GB9106465D0 (en) 1991-03-26 1991-03-26 Acoustic flowmeter
GB9314722A Expired - Fee Related GB2267568B (en) 1991-03-26 1993-07-16 Acoustic flowmeter

Family Applications Before (1)

Application Number Title Priority Date Filing Date
GB919106465A Pending GB9106465D0 (en) 1991-03-26 1991-03-26 Acoustic flowmeter

Country Status (3)

Country Link
EP (1) EP0577679A1 (en)
GB (2) GB9106465D0 (en)
WO (1) WO1992017753A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4556253B2 (en) * 1999-06-24 2010-10-06 パナソニック株式会社 Flowmeter
EP2642256B1 (en) 2012-03-23 2018-07-18 ams AG Measurement arrangement and method

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3307408A (en) * 1966-08-10 1967-03-07 Int Research & Dev Co Ltd Synchronous filter apparatus in which pass-band automatically tracks signal, useful for vibration analysis
US3949605A (en) * 1974-07-02 1976-04-13 The United States Of America As Represented By The Secretary Of The Navy Acoustic current/flow measuring system
EP0250660A1 (en) * 1986-06-05 1988-01-07 Moore Products Co. Fluid velocity measuring method and apparatus
GB2205645A (en) * 1987-06-12 1988-12-14 Milan Herman Miessler Fluid flow measurement

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3307408A (en) * 1966-08-10 1967-03-07 Int Research & Dev Co Ltd Synchronous filter apparatus in which pass-band automatically tracks signal, useful for vibration analysis
US3949605A (en) * 1974-07-02 1976-04-13 The United States Of America As Represented By The Secretary Of The Navy Acoustic current/flow measuring system
EP0250660A1 (en) * 1986-06-05 1988-01-07 Moore Products Co. Fluid velocity measuring method and apparatus
GB2205645A (en) * 1987-06-12 1988-12-14 Milan Herman Miessler Fluid flow measurement

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
EDN ELECTRICAL DESIGN NEWS. Vol.31,no.7, April 1986, NEWTON,MASSACHUSETTS US pages 119 - 126. *

Also Published As

Publication number Publication date
GB9106465D0 (en) 1991-05-15
EP0577679A1 (en) 1994-01-12
WO1992017753A1 (en) 1992-10-15
GB9314722D0 (en) 1993-09-29
GB2267568B (en) 1994-08-03

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Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 20080325