CN112414482A - Ultrasonic fluid metering transducer based on digital technology - Google Patents
Ultrasonic fluid metering transducer based on digital technology Download PDFInfo
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- CN112414482A CN112414482A CN202011243277.9A CN202011243277A CN112414482A CN 112414482 A CN112414482 A CN 112414482A CN 202011243277 A CN202011243277 A CN 202011243277A CN 112414482 A CN112414482 A CN 112414482A
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- 238000005516 engineering process Methods 0.000 title claims abstract description 24
- 239000012530 fluid Substances 0.000 title claims abstract description 20
- 238000012545 processing Methods 0.000 claims abstract description 22
- 230000005284 excitation Effects 0.000 claims abstract description 17
- 230000008859 change Effects 0.000 claims abstract description 5
- 238000005070 sampling Methods 0.000 claims description 13
- 238000006243 chemical reaction Methods 0.000 claims description 11
- 230000004044 response Effects 0.000 claims description 4
- 239000003292 glue Substances 0.000 claims description 3
- 238000007711 solidification Methods 0.000 claims description 3
- 230000008023 solidification Effects 0.000 claims description 3
- 238000003860 storage Methods 0.000 claims description 3
- 238000013461 design Methods 0.000 abstract description 3
- 230000005540 biological transmission Effects 0.000 description 5
- 238000005259 measurement Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 238000004891 communication Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000005236 sound signal Effects 0.000 description 3
- 230000003068 static effect Effects 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 239000000919 ceramic Substances 0.000 description 2
- 230000003111 delayed effect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000008054 signal transmission Effects 0.000 description 2
- 241000659073 Achaea echo Species 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 230000026683 transduction Effects 0.000 description 1
- 238000010361 transduction Methods 0.000 description 1
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- 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
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Transducers For Ultrasonic Waves (AREA)
Abstract
The invention relates to an ultrasonic fluid metering transducer based on digital technology, which comprises: a transducer base unit having a cavity in which the described sound (acoustic wave) generating unit and sound (acoustic wave) receiving unit can be placed is required; the excitation device drives the initial transducer which generates the sound wave according to the driving signal; the modulation device samples the output signal of the sound wave receiving unit according to the amplitude change of the output signal of the sound wave signal received by the initial transducer; the driving signal presetting device is used for calculating echo signals, and according to the result of calculating the echo signals, the operation circuit unit adjusts the pulse number and the pulse period (frequency) of driving pulses according to the result, so that the transducer basic unit obtains proper driving signals, and the receiving transducer receives proper echo signals, and the scheme is simple and clear; the design and implementation difficulty of a signal processing circuit of an ultrasonic metering application scheme is reduced.
Description
Technical Field
The present invention relates to a radio frequency output/receiving device in conventional information communication equipment, electroacoustic equipment, measuring instrument and system for processing sound, in particular, it relates to an ultrasonic fluid metering transducer based on digital technology.
Background
With the further deepening of the reform, the coal-to-gas work is promoted, the development of intelligent water affairs is promoted, the intelligent degree of the metering instrument is greatly improved, and the fluid metering instrument including a gas meter and a water meter is promoted to develop towards the direction of safer, more reliable, more intelligent and higher metering precision; the main functions are divided into the following aspects, metering (magnetic metering, non-magnetic metering, photoelectric metering and ultrasonic metering), remote communication (metering data uploading) and local communication (configuration parameters).
The demand of higher metering precision prompts the electronic fluid meter to gradually replace the mechanical fluid meter, and the transducer for fluid metering is the core device of the ultrasonic fluid meter.
In the conventional transducer, electrical-to-acoustic transmission is excited by digital pulses, acoustic-to-electrical echo signal transmission is analog millivolt-level small signals, and the analog small signals are processed (amplified and filtered) in a circuit unit, but the signal-to-noise ratio of the transmitted analog signals is extremely large, so that the lower limit of the small flow meter is limited. Transducer digitization is used for metrology performance, integration, consistency, and cost considerations.
The ultrasonic measurement of gas and water meter is a fluid electronic meter using ultrasonic measurement technology, and the core technical theory and difficulty is the analog small signal processing after the sound-to-electric conversion. The following difficulties exist in the processing:
a. echo signals, the signal-to-noise ratio is low;
b. the transmission process of the echo signal is easily subjected to crosstalk;
c. the problem of co-channel interference;
d. simulating the problem of small signal transmission attenuation;
e. residual vibration of the transducer and static charge of the cavity in the shell cause the amplitude of the signal to be reduced.
These difficulties lead to the fact that the threshold for popularizing the metering technology is raised, the development of the fluid metering technology is indirectly delayed, and the popularization schedule is delayed.
Disclosure of Invention
In view of the above-mentioned prior art, the technical problem to be solved by the present invention is to provide an ultrasonic fluid metering transducer based on digital technology, which reduces the design and implementation difficulty of the signal processing circuit of the ultrasonic metering application scheme.
The technical scheme adopted by the invention for solving the technical problems is as follows: an ultrasonic fluid metering transducer based on digital technology, comprising:
a transducer base unit having a cavity in which the described sound (acoustic wave) generating unit and sound (acoustic wave) receiving unit can be placed is required;
the excitation device drives the initial transducer which generates the sound wave according to the driving signal;
the modulation device samples the output signal of the sound wave receiving unit according to the amplitude change of the output signal of the sound wave signal received by the initial transducer;
and the driving signal presetting device is used for calculating the echo signal, and according to the result of calculating the echo signal, the calculating circuit unit adjusts the pulse number and the pulse period (frequency) of the driving pulse according to the result, so that the transducer basic unit obtains a proper driving signal, and the receiving transducer receives a proper echo signal.
Further, each transducer base unit includes: vibration conducting layer, hollow cavity, piezoelectric transducer, matching soft solidification body, hard glue body and village bottom.
Further, the transducer base unit is connected with the circuit processing unit and is provided with an impedance conversion circuit.
Further, the excitation device comprises an electrode driving power supply; and the electrode driving circuit is used for connecting and disconnecting the transducer basic unit and the electrode driving power supply and is connected with the excitation driving signal correspondingly.
Further, the modulation apparatus includes: a preamplifier, a sample-and-hold circuit and a delta-debug circuit.
Further, the preamplifier: for amplifying the output signal of the sound (echo) receiving unit; a sample-and-hold circuit: sampling an output signal of the preamplifier according to a predetermined excitation pulse frequency; debugging the circuit: the output signal for the sampling circuit is compared with a set threshold value to obtain one code symbol of the code pulses "1" and "0".
Further, the drive signal presetting device includes: an arithmetic circuit and a signal driving circuit.
Further, the arithmetic circuit: the digital signal processing circuit is used for coding a coded pulse signal output by a debugging circuit into a binary value and is divided into 2 paths, one path of transmission and external devices (storage, conversion and processing), and the other path of transmission and external devices adjusts a driving signal, pulse quantity and adjusting frequency according to received data and transmits the driving signal, the pulse quantity and the adjusting frequency to a signal driving circuit; the signal driving circuit: the signal output from the arithmetic circuit is sampled in response to a clock frequency matching an interface for connection between the "ultrasonic metering transducer for digital technology" and the outside, and the sampled signal is supplied as the drive signal to a drive device as the drive signal and a predetermined form (number of pulses, frequency).
Further, the charges are applied to the transducer initial unit, the static charges drive the piezoelectric converter to generate partial deformation, vibration is generated to generate sound waves, and otherwise the sound waves enable the piezoelectric converter to be deformed to generate the charges to form an electret shape.
Compared with the prior art, the invention has the advantages that: the scheme of the invention is simple and clear; the design and implementation difficulty of a signal processing circuit of an ultrasonic metering application scheme is reduced; functionally, a sound (sound wave) generating unit that converts an electric signal into sound (vibration sound wave); the device is provided with a sound (sound wave) receiving unit, transmits the sound (sound wave) to the piezoelectric ceramics according to the action on the vibration conduction layer, generates electric charge according to the deformation of the piezoelectric ceramics and outputs a corresponding output electric signal.
Drawings
FIG. 1 is a block diagram of the circuit elements of a digital ultrasonic metering transducer of the present invention;
FIG. 2 is a functional block diagram of a digital ultrasonic measurement transducer of the present invention;
FIG. 3 is a schematic diagram of a digital ultrasonic metrology transducer of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings.
A transducer base unit having a cavity in which the described sound (acoustic wave) generating unit and sound (acoustic wave) receiving unit can be placed is required;
the excitation device drives the initial transducer which generates the sound wave according to the driving signal;
the modulation device samples the output signal of the sound wave receiving unit according to the amplitude change of the output signal of the sound wave signal received by the initial transducer;
and the driving signal presetting device is used for calculating the echo signal, and according to the result of calculating the echo signal, the calculating circuit unit adjusts the pulse number and the pulse period (frequency) of the driving pulse according to the result, so that the transducer basic unit obtains a proper driving signal, and the receiving transducer receives a proper echo signal.
Ultrasonic measurement transducer of digital technique, every transducer basic unit includes: the vibration conduction layer, the hollow cavity, the piezoelectric conversion body, the matched soft solidification body, the hard glue body and the village bottom;
the ultrasonic metering transducer of the digital technology, the basic unit of the transducer is connected with circuit processing unit and has impedance conversion circuit;
the ultrasonic measuring transducer of digital technology, the exciting arrangement includes, the electrode drives the power; the electrode driving circuit is used for connecting and disconnecting the transducer basic unit and the electrode driving power supply and corresponds to the connection of the excitation driving signal;
ultrasonic measuring transducer of digital technique, modulating device includes: the device comprises a preamplifier, a sample-hold circuit and a debugging circuit;
a preamplifier: for amplifying the output signal of the sound (echo) receiving unit;
a sample-and-hold circuit: sampling an output signal of the preamplifier according to a predetermined excitation pulse frequency;
debugging the circuit: the output signal of the sampling circuit is compared with a set threshold value, so that one code symbol of code pulses '1' and '0' is obtained;
the ultrasonic metering transducer of digital technique, the preset device of the driving signal includes: an arithmetic circuit and a signal driving circuit;
an arithmetic circuit: the digital signal processing circuit is used for coding a coded pulse signal output by a delta debugging circuit into a binary value, and is divided into 2 paths, one path is transmitted to an external device (storage, conversion and processing), and the other path adjusts a driving signal, the pulse number and the adjusting frequency according to received data and transmits the driving signal, the pulse number and the adjusting frequency to a signal driving circuit;
the signal driving circuit: sampling a signal output from the arithmetic circuit in response to a clock frequency matching an interface for connection between the "ultrasonic metering transducer for digital technique" and the outside, and supplying the sampled signal as the drive signal to a drive device as the drive signal and a predetermined form (number of pulses, frequency);
the ultrasonic metering transducer of the digital technology is characterized in that charges are applied to an initial unit of the transducer, static charges drive a piezoelectric converter to generate partial deformation to generate vibration to generate sound waves, and otherwise the sound waves enable the piezoelectric converter to generate the charges through deformation to form an electret shape;
in order to achieve the purpose, the ultrasonic fluid metering transducer of the digital technology comprises a transducer base unit, a transducer base unit and a transducer base unit, wherein the transducer base unit is used for converting an electric signal into a sound wave (sound) and also converting the sound wave (sound) into the electric signal; the electric signal link of the transducer basic unit is connected with the circuit processing unit, the exciting device drives the transducer basic unit (piezoelectric converter) according to the driving signal, the modulating device samples the output signal of the sound wave receiving unit according to the amplitude change of the output signal of the transducer basic unit to generate a pulse, the driving signal presetting device is used for calculating an operation digital signal and outputting the operation digital signal to the peripheral instrument circuit for processing, the other signal is used for internal closed loop processing, the pulse from the modulating device according to the operation signal is used for enabling the transducer basic unit to obtain proper amplitude by changing the number and frequency of the pulse, and the digital audio signal input by an external circuit is superposed with the digital audio signal to synthesize the driving signal of the exciting device.
The conversion of the echo analog signal into the digital signal is high in efficiency, and the electro-acoustic transduction and the digital-analog conversion of the circuit processing unit are synchronously carried out. When the applied digital electrical signal has a fixed voltage to the driven unit while ensuring that the upper limit of the clock frequency is sufficiently high, the frequency characteristic of the signal driving capability can be understood as being flat and linear.
The sound emitted by the transmitting transducer is detected by the receiving transducer piezoelectric transducer. The piezoelectric transducer is connected to a terminal circuit (circuit processing unit) from which an acoustic echo signal is obtained. This signal is amplified by a preamplifier, and then sampled by a high-speed clock sampling signal (sampling the input signal) in a sample-and-hold circuit. The value of the sampled signal is compared with the signal value sampled in the delta debugging circuit to obtain a sampling envelope. When the sampling point of the sampling envelope is less than or equal to the threshold level, no output pulse, namely 0, is generated; conversely, a high level pulse, i.e., "1"; the resulting output pulse is supplied to the digital signal of the arithmetic circuit. The operation circuit accumulates and outputs a pulse value to obtain a new excitation operation signal; meanwhile, the output pulse signal is transmitted back to the system core processing circuit unit.
When no digital excitation signal is supplied to the signal input/output terminal from the outside, only a signal generated by a sound pressure driving force acting on a vibration conduction layer of the transducer base unit is amplified, sampled, and supplied to the arithmetic circuit. The excitation signal providing circuit samples binary digital signals generated by a clock signal matched with an interface of the measuring transducer and an external link through the arithmetic circuit, sums the sampled signals with digitized sound pressure signals sent to the arithmetic circuit to generate reverse phase signals to be provided for the electrode driving circuit, and provides electric energy from a driving power supply to the electrode driving circuit to eliminate residual vibration of the transducer.
The frequency of the sampling clock signal is settable and can be 2 times or 2n times, so that direct conversion between the analog signal and the digital signal sound is obtained. Meanwhile, the sound pressure generated by the noise in the hollow housing and the composite sound pressure emitted by the circuit processing unit in response to the signal provided from the arithmetic circuit through the signal driving circuit and the electrode driving circuit are balanced within an error redundancy range. The output signal of the transducer basic unit is in the closed-loop control of the arithmetic circuit, so that the output signal is controlled in a proper range. The digital excitation audio signal is supplied to the digital input/output terminal, superimposed on the arithmetic signal in the arithmetic circuit, thereby realizing transmission of the excitation signal.
Claims (9)
1. An ultrasonic fluid metering transducer based on digital technology, comprising:
a transducer base unit having a cavity in which the described sound (acoustic wave) generating unit and sound (acoustic wave) receiving unit can be placed is required;
the excitation device drives the initial transducer which generates the sound wave according to the driving signal;
the modulation device samples the output signal of the sound wave receiving unit according to the amplitude change of the output signal of the sound wave signal received by the initial transducer;
and the driving signal presetting device is used for calculating the echo signal, and according to the result of calculating the echo signal, the calculating circuit unit adjusts the pulse number and the pulse period (frequency) of the driving pulse according to the result, so that the transducer basic unit obtains a proper driving signal, and the receiving transducer receives a proper echo signal.
2. The digital technology based ultrasonic fluid metering transducer of claim 1, wherein each transducer base unit comprises: vibration conducting layer, hollow cavity, piezoelectric transducer, matching soft solidification body, hard glue body and village bottom.
3. The digital technology based ultrasonic fluid metering transducer of claim 1, wherein the transducer base unit is connected with a circuit processing unit and is provided with an impedance conversion circuit.
4. An ultrasonic fluid-metering transducer based on digital technology according to claim 1, characterised in that the excitation means comprises an electrode drive power supply; and the electrode driving circuit is used for connecting and disconnecting the transducer basic unit and the electrode driving power supply and is connected with the excitation driving signal correspondingly.
5. An ultrasonic fluid-metering transducer based on digital technology according to claim 1, characterised in that the modulation means comprise: a preamplifier, a sample-and-hold circuit and a debug circuit.
6. The digital technology based ultrasonic fluid metering transducer of claim 5, wherein the preamplifier: for amplifying the output signal of the sound (echo) receiving unit; a sample-and-hold circuit: sampling an output signal of the preamplifier according to a predetermined excitation pulse frequency; debugging the circuit: the output signal for the sampling circuit is compared with a set threshold value to obtain one code symbol of the code pulses "1" and "0".
7. An ultrasonic fluid-metering transducer based on digital technology according to claim 1, characterized in that the drive signal presetting device comprises: an arithmetic circuit and a signal driving circuit.
8. The digital technology based ultrasonic fluid metering transducer of claim 7, wherein the operational circuitry: the digital signal processing circuit is used for coding a coded pulse signal output by a delta debugging circuit into a binary value, and is divided into 2 paths, one path is transmitted to an external device (storage, conversion and processing), and the other path adjusts a driving signal, the pulse number and the adjusting frequency according to received data and transmits the driving signal, the pulse number and the adjusting frequency to a signal driving circuit; the signal driving circuit: the signal output from the arithmetic circuit is sampled in response to a clock frequency matching an interface for connection between the "ultrasonic metering transducer for digital technology" and the outside, and the sampled signal is supplied as the drive signal to a drive device as the drive signal and a predetermined form (number of pulses, frequency).
9. The ultrasonic fluid metering transducer based on the digital technology as claimed in claim 1, wherein the electric charges are applied to an initial unit of the transducer, the electrostatic charges drive the piezoelectric transducer to generate partial deformation to generate vibration to generate sound waves, and the sound waves cause the piezoelectric transducer to generate electric charges to form an electret shape.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011243277.9A CN112414482A (en) | 2020-11-10 | 2020-11-10 | Ultrasonic fluid metering transducer based on digital technology |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011243277.9A CN112414482A (en) | 2020-11-10 | 2020-11-10 | Ultrasonic fluid metering transducer based on digital technology |
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| CN112414482A true CN112414482A (en) | 2021-02-26 |
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| CN202011243277.9A Pending CN112414482A (en) | 2020-11-10 | 2020-11-10 | Ultrasonic fluid metering transducer based on digital technology |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002236040A (en) * | 2001-02-08 | 2002-08-23 | Matsushita Electric Ind Co Ltd | Flow rate measuring apparatus |
| US20020124662A1 (en) * | 2001-02-28 | 2002-09-12 | Matsushita Electric Industrial Co., Ltd | Ultrasonic transducer, method for manufacturing ultrasonic transducer, and ultra sonic flowmeter |
| CN101093172A (en) * | 2002-06-04 | 2007-12-26 | 东京电力株式会社 | Doppler type ultrasonic flowmeter, flow rate measuring method |
| FR2952221A1 (en) * | 2009-10-29 | 2011-05-06 | Bosch Gmbh Robert | Ultrasonic transducer for use in fluid environment e.g. gas and/or liquid such as air or exhaust fumes, has damping element equipped at outer side of cavity for dampening structure-borne noise |
| CN102265332A (en) * | 2008-12-23 | 2011-11-30 | 罗伯特·博世有限公司 | Ultrasonic transducer for use in a fluid medium |
| JP2012107874A (en) * | 2010-11-15 | 2012-06-07 | Panasonic Corp | Ultrasonic flowmeter |
| CN111157623A (en) * | 2020-01-17 | 2020-05-15 | 中山大学 | High-power self-adaptive ultrasonic pulse emission and nonlinear ultrasonic guided wave measuring device |
-
2020
- 2020-11-10 CN CN202011243277.9A patent/CN112414482A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002236040A (en) * | 2001-02-08 | 2002-08-23 | Matsushita Electric Ind Co Ltd | Flow rate measuring apparatus |
| US20020124662A1 (en) * | 2001-02-28 | 2002-09-12 | Matsushita Electric Industrial Co., Ltd | Ultrasonic transducer, method for manufacturing ultrasonic transducer, and ultra sonic flowmeter |
| CN101093172A (en) * | 2002-06-04 | 2007-12-26 | 东京电力株式会社 | Doppler type ultrasonic flowmeter, flow rate measuring method |
| CN102265332A (en) * | 2008-12-23 | 2011-11-30 | 罗伯特·博世有限公司 | Ultrasonic transducer for use in a fluid medium |
| FR2952221A1 (en) * | 2009-10-29 | 2011-05-06 | Bosch Gmbh Robert | Ultrasonic transducer for use in fluid environment e.g. gas and/or liquid such as air or exhaust fumes, has damping element equipped at outer side of cavity for dampening structure-borne noise |
| JP2012107874A (en) * | 2010-11-15 | 2012-06-07 | Panasonic Corp | Ultrasonic flowmeter |
| CN111157623A (en) * | 2020-01-17 | 2020-05-15 | 中山大学 | High-power self-adaptive ultrasonic pulse emission and nonlinear ultrasonic guided wave measuring device |
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Application publication date: 20210226 |