SU1095039A1 - Device for measuring speed of ultrasound materials - Google Patents

Abstract

A device for measuring the speed of ultrasound in a material, containing a series-connected synchronizer, a generator of pulses KHpJX pulses and an emitting electro-acoustic transducer, a receiving electro-acoustic transducer, an amplifier with automatic gain control, the input of which is connected to the output of the electro-acoustic transducer, an amplifier with an automatic gain control, whose input is connected to the output of the acoustic transducer, and the pattern has a closed pattern and has a pattern and has a pattern and a teller pattern, the pattern and the tweeter are connected to the receiver. automatic gain control, first threshold block whose input is connected to the output ohm analog key, a generator of forbidden pulses, the first input of which is connected to the output of the first threshold unit, the second input - to the synchronizer output, a first output - to the second input of the analog key, the second threshold unit, the input of which is connected to the output of the analog key, the first circuit And , the first input of which is connected to the output of the second threshold unit, a second input is connected to the second output of the forbidden pulse generator, the first unit of time, the first input of which is connected to the output of the first AND circuit, and the second input - from the output synchronizer house, time converter into a digital code, i the first input of which is connected to the output of the first time master, (L characterized in that, with: in order to improve the measurement accuracy, it is equipped with a third threshold unit, a second And circuit and a second time master, the input of the third threshold unit is connected to the output of the analog switch, a output connects to the first input of the second circuit And, the second coaxial input of the latter is connected to the output of the first time master, the output is with a co; o the input of the second time master, a out One of the latter is connected to the second input of the time interval converter into a digital code.

Description

The invention relates to a measurement technique and can be used, in particular, to control product quality in mechanical engineering, metallurgy and other industries.

A device for measuring the speed of ultrasound in materials is known, comprising a synchronizer connected in series, a probe pulse generator and an electroacoustic transducer, an amplifier receiving transducer with automatic gain control, the input of which is connected to the output of a receiving electroacoustic converter, an analog switch which input is connected to the output of amplifier automatic gain control, the first threshold unit whose input is connected with the output of the analog key, the generator of forbidden pulses, the first input of which is connected to the output of the first threshold unit, the second input - to the synchronizer output, and the first output - to the second input of the analog key, the second threshold unit, the input of which is connected to the output of the analog key, first circuit And, the first input of which is connected to the output of the second threshold unit, and the second input is connected to the second output of the forbidden pulses generator, the first time master, the first input of which is connected to the output of the first And circuit, and the second input - with a synchronizer output, a time interval converter into a digital code, the first input of which is connected to the output of the first time master Sch. The disadvantage of this device is the low accuracy of the ultrasound velocity measurements.

The purpose of the invention is to improve the measurement accuracy.

The goal is achieved by the fact that a device for measuring the velocity of ultrasound in materials, containing a series-connected synchronizer, probe pulse generator and radiating electro-acoustic transducer, receiving electro-acoustic transducer, amplifier with automatic (gain control, input of which is connected to the output of the receiving electro-acoustic transducer, analog key whose input is connected to the output of the amplifier with automatic gain control, the first thresholds th block, the input of which is connected to the 5 output of the analog key, the generator of forbidden pulses, the first input of which is connected to the output of the first threshold unit, the second input to the synchronizer output, and the first

® output - with the second input of the analog switch, the second threshold unit, the input of which is connected to the output of the analog switch, the first And circuit, the first input of which is connected to the code

5 of the second threshold unit, and the second input is connected to the second output of the forbidden pulse generator, the first time master, the first input of which is connected to the output of the first circuit

0 and, and the second input - with the synchronizer output, the time interval converter into the digital code, the first input of which is connected to the output of the first time master, is equipped with

5 third threshold block, the second

And the second time setting device, the input of the third threshold block is connected to the output of the analog switch, and the output is connected to the first input of the second AND connection, the second input of the last is connected to the output of the first time setting device, the output is connected to the input of the second time setting device connected to the second input of the time interval converter into a digital code.

FIG. 1 is a block diagram of a device for measuring ultrasound velocity; in fig. 2 - stress diagrams.

The device contains a synchronizer 1, a generator of 2 probe pulses, an emitting electroacoustic transducer 3, a receiving electroacoustic transducer 4, an amplifier 5 with automatic gain control, an analog switch 6, the first threshold unit 7, the generator 8 forbidden pulses, the second threshold unit 9, the first circuit And 10 and the first unit 11 of time, the Converter 12 time interval into a digital code, the third threshold unit 13, the second circuit And 14 and the second unit 15

of time.

The device works as follows. The synchronizer 1 generates pulses (Fig. 2.0), triggering the generator 2 probe pulses. The latter excites a radiating electroacoustic transducer 3, which emits ultrasonic pulses of oscillations into the article under study (not indicated). The receiving electroacoustic transducer 4 receives these ultrasonic pulses, converting them into electrical pulses. An amplifier 5 with automatic gain control maintains a constant amplitude of the first half-wave of the received pulse signal (Fig. 2, b), which is fed to the analog key 6. The first threshold unit 7, tuned to the second half-wave of the received signal, produces a pulse (Fig. 2, i) which goes to the first input of the 8 forbidden pulses generator, to the second input of which I get the pulse from the output of the synchronizer 1 (Fig. 2, a). The generator 8 of the forbidden pulses contains a pulse (Fig. 2.4), the beginning of which corresponds to the start time of the generator 2 probe pulses (Fig. 2, a), and the end - the moment of the beginning of the pulse output by the first threshold unit 7 (Fig. 2.6) . This pulse (Fig. 2, i) is fed to the second input of the analog switch 6, to the first input of which a signal comes from the output of the amplifier 5 with automatic gain control (Fig. 2, K); The output of the analog key 6 passes the first half-wave of the received signal (Fig. 2). The threshold blocks 9 and 13 operate from the leading edge of the received signal, and the trigger level of threshold block 9 is higher than the trigger threshold of block 13. Threshold blocks 9 and 13 pick pulses that go to the first inputs of the first and second circuits And 10 and 14. To the second input of the first circuit AND 10, the signal from the second code of the generator1 394 rator of 8 forbidden pulses (figure 2, circuit 10) produces a pulse (fig. 2, c) which goes to the first input of the first time sensor 11, to the second input of which signal is coming from sync output Ator 1. Timer 11 generates a pulse (Fig. 2, "Jc), which is fed to the second input of the second circuit AND 14 and to the first input of the transducer-t l 12 time interval into a digital code. The duration of this pulse (Fig. 2, X, the true time of propagation of ultrasonic oscillations in the product under study, is measured in measurement due to the response level of the second threshold unit 9. A second circuit 14 produces a pulse, the duration of it, (FIG. 2, U) which corresponds to the difference between the levels of operation of the threshold blocks 9 and 13. The pulse from the output of the circuit 14 goes to the second time master 15, which performs the operation of multiplying by a factor, so that & i - O.: - ut . The signal from the output of the second unit 15 of time is fed to the second input of the Converter 12 time interval in the digital code. The 12 V1 converter of the interval into the digital code performs the operation of subtracting the pulses arriving at its inputs so that the duration of the resulting pulse is equal to the propagation time of the ultrasonic oscillations in the article under study. The use of a device for measuring the speed of ultrasound makes it possible to increase the accuracy of measurements.

Claims (1)

DEVICE FOR MEASURING THE SPEED OF ULTRASOUND IN MATERIALS, containing a synchronizer, a probe pulse generator and a radiating electro-acoustic transducer, a receiving electro-acoustic transducer, an amplifier with automatic gain control, the input of which is connected to the output of the receiving electro-acoustic transducer, an analog key, the input of which is connected to the output automatic gain control, the first threshold block, the input of which is connected to the output a log key, a forbidden pulse generator, the first input of which is connected to the output of the first threshold block, the second input - to the output of the synchronizer, and the first output - to the second input of the analog key, the second threshold block, the input of which is connected to the output of the analog key, the first AND circuit, the first input of which is connected to the output of the second threshold block, and the second input is connected to the second output of the forbidden pulse generator, the first time clock, the first input of which is connected to the output of the first circuit And, and the second input to the synchronous output isator, a time interval converter into a digital code, the first input of which is connected to the output of the first time clock, characterized in that, in order to improve the measurement accuracy, it is equipped with a third threshold block, a second circuit I and a second time clock, the input of the third the threshold block is connected to the analog key output, and the output is connected to the first input of the second AND circuit, the second input of the last is connected to the output of the first time clock, the output is connected to the input of the second time clock, and the output of the last is connected to the second input The time converter to digital code. f