SU1234767A1 - Ultrasonic speed meter - Google Patents

Abstract

This invention relates to a measurement technique and can be used to measure the speed of ultrasound in various media. In order to improve speed, the probe pulse generator 7 excites the ultrasonic emitter 8, the signal of which is received by the ultrasonic receiver I, is amplified by the amplifier 2 and is fed to the first input of the pulse phase comparator 3, to the second input of which the signal from the square-wave generator 5 divided by is received. frequency divider 6 frequency. The error signal from the output of the phase comparator 3, integrated by integrator 4, controls the frequency of the oscillator 5 square wave so that the half voltage of the square wave becomes equal to the propagation time of the ultrasonic signal in the studied medium between the ultrasonic emitter 8 and the receiver 1. To measure the measurement accuracy by eliminating depending on the measurement result on the delay in the elements of the device, the output of the frequency divider 6 is connected to the second input of the phase comparator 3 via the delay element 9. 1 hp f-ly, 1 ill. i. (Lü so 4 05

Description

one

The invention relates to a measurement technique and can be used to measure the time and speed of propagation of ultrasonic vibrations in various media.

The purpose of the invention is to increase speed and accuracy.

The drawing shows a structural diagram of the meter.

The device contains a series-connected ultrasonic receiver 1, amplifier 2, pulse phase comparator 3, integrator 4, generator 5, frequency divider 6 and probe pulses generator 7 and ultrasonic emitter 8. Generator 5 and divider 6 form an oscillator. The output of the frequency divider 6 is further connected to the second input of the pulsed phase comparator 3 either directly or to improve the measurement accuracy through the delay unit 9.

The device works as follows.

The probe pulse generator 7 excites the ultrasonic emitter 8. The acoustic signal is received by the ultrasonic receiver 1 and the electrical signal from its output is amplified by the amplifier 2 and is fed to the input of the pulse phase comparator 3. The first positive voltage front of the meander from the frequency divider 6 passes to the comparative input of the pulse phase comparator 3, the output of which in the initial state was the average value of the voltage. After a signal arrives, this voltage either decreases or increases, depending on which of the signals at its two inputs came first. The error signal from the output of the comparator 3 controls the frequency of the oscillator 5 so that the half-period eg Editor L. Avramenko

Compiled by L. Kondrykinsk

Tehred I.Popovich Proofreader I.Musk

Order 2979/48 Circulation 778 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

ten

34767

the meander becomes equal to the time of the ultrasonic signal propagation through the test medium between the ultrasonic emitter 8 and the ultrasonic receiver 1.

To increase the measurement accuracy between the output of the frequency divider and the input of the pulsed phase comparator 3, a delay unit 9 is included which makes the measurement result independent of the delay in other elements of the measurement circuit.

The invention makes it possible to increase the measurement speed by reducing the transients of the following system over the half-period of the square wave voltage and to increase the accuracy by reducing the effect of delays in the electrical circuits, and thereby increasing the noise immunity from the interference of multiple reflections of ultrasound.

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20

Formula inventions

Claims (2)

1. Measuring the speed of ultrasound, containing series-connected probe pulse generator and ultrasonic emitter, ultrasonic receiver and amplifier, an integrator, a generator and a frequency divider, the output of which is connected to the input of the probe pulse generator, characterized in that, in order to improve speed, it equipped with a pulse phase comparator, the first input of which is connected to the output of the amplifier, the second input - to the output of the frequency divider, and the output - to the input of the integrator. 2. Pop-1 meter, characterized in that, in order to improve accuracy, it is equipped with a delay unit connected between the second input of the pulse phase comparator and the output of the frequency divider,