SU666962A1 - Device for measuring ultrasonic velocity in materials - Google Patents

Abstract

ULTRASONIC SPEED METER IN THE MATERIAL, containing serially connected synchronizer, ultrasonic oscillator and piezotransducer, receiver, gating pulse generators, whose inputs are connected to the synchronizer, selectors of useful signals, time-frequency converter connected to the outputs of the latter, counting pulse generator, switch, serially connected selector unit, counting unit, digital indicator, and adjustable single-vibrator, the output of which is connected selector unit., characterized in that, in order to improve measurement accuracy, it is equipped with series-connected cascade connected to the output of the receiver, a frequency divider, two triggers connected between strobe generators and selectors of the useful signal, the second inputs of the trigger and selectors of the useful signal are connected respectively to each other and to the output of a frequency divider, a time delay unit connected between the output of the synchronizer and the input of the adjustable one-oscillator.

Description

CD 0: 5 U The invention relates to a measuring technique and can be used in devices for measuring the speed of ultrasound in various materials. A device for measuring the speed of ultrasound in materials is known, comprising a modulator connected in series, a frequency divider, a synchronization unit, the second input of which is connected to the modulator, a generator, a piezo transducer, a receiver, a former, a time discriminator, a control unit connected to the input of the module a torus, a phasing unit whose input is connected to the modulator output, a gate trigger, the output of which is connected to the second | discriminator input, a measuring unit connected to the modulator output, and selec a torus whose input is connected to the generator output, and an output to the input of the forming unit 1; Also known is an ultrasound velocity meter in materials containing a synchronously connected synchronizer, an ultrasonic oscillator and a piezoelectric transducer, generators of gates pulses, whose inputs are connected to the synchronizer, selectors useful signals, a time interval to frequency converter connected to the outputs of the latter, a generator of counting pulses, a switch, sequentially connected Vectorial block counting unit, a digital display and adjustment monostable multivibrator, whose output is connected to the selector block 2. The disadvantage of such devices is the low accuracy of measurement. The purpose of the invention is to improve the measurement accuracy. This is achieved by the fact that the meter is equipped with a series-connected forming cascade connected to the receiver output, a frequency divider, two triggers connected between the strobe generators and selectors of the useful signal, the second inputs of the triggers and selectors of the useful signal are connected between each other and with you the course of the frequency divider, the time delay unit connected between the synchronizer output and the input of the controlled one-shot. The drawing shows a block diagram of the meter. The meter contains sequentially connected synchronizer 1, gannator 2 ultrasonic vibrations and. a piezoelectric transducer 3, a receiver 4, 5- and 6-gating pulse generators, whose inputs are connected to a synchronizer. And the outputs are in series with selectors 7 and 8 of useful signals and an interval-to-frequency converter 9, a generator of 10 counting pulses, a switch 11 connected in series the selector unit 12, the counting unit 13, a digital indicator 14 and an adjustable one-shot 15, the output of which is connected to the block 12, a time delay flea 16, the input of which is connected to the synchronizer 1, and the output to the adjustable one-shot 15, and that Also, the flip-flops 17 and 18 are connected, respectively, between the outputs of the gates 5 and 6 of the gating pulses and the inputs of the selectors 7 and 8 of the useful signals, the second inputs of which and the second inputs of the flip-flops 17 and 18 are connected in parallel with each other and connected in series. The frequency separator 19 and the cascade 20 - with the output of the receiver 4. The meter works as follows. The synchronization pulse triggered by torus 1 and the ultrasound generator 2 (the pulses are excited with the help of a piezo-transducer 3 in a 2: 1 product, ultrasonic, and sonic vibrations. Ultrasonic vibrations, repeatedly reflected from the plane-parallel edges of the product 21, are converted into electrical pulses by the piezoelectric transducer 3 and, together with the probes pulses after amplification in receiver 4 arrive at cascade 20, which converts the positive half cycles of radio pulses into rectangular pulses. As a formative cascade 20, you can The Schmidt trigger is applied, for example. From cascade 20, a sequence of rectangular pulses goes to frequency divider 19 with a division factor n, for which, for example, a trigger in counting mode can be applied. Thus, from the output of frequency divider 19, of the impulses whose duration is equal to fi / 2f, where is the frequency of the radio pulses of the generator 2. Using the generators 5 and 6 of the gating pulses, the trigger 17 and 18 of the selectors 7 and 8 of the useful signals, the fronts of the half semiconductors are allocated The periods of the two ultrasonic radio pulses repeatedly reflected from the plane-parallel faces of the product 21. The speed is measured as follows. Switch 11 to the entrance of the unit 12 connects the generator of 10 counting pulses, the period of which is stable. Then, by adjusting the pulse duration of the one-shot 15 on the digital indicator 14, the thickness of the product 21 is set to 3. f 669624

Rum is necessary to measure the speed of which quality can be ultrasound. Last measured by user, for example, odiovibrator,

connecting to block 12 conversion-duration of which varies by

tel 9 using the switch 11. noise law. Thanks to this when

In this run one-shot 15 vibrator (for example,) will be erroneous from the time delay unit 16, the measurement accuracy decreases by a factor of

averaging the measurement result for

Claims (1)

ULTRASONIC SPEED MEASURER IN MATERIALS, containing a synchronizer, a ultrasonic oscillator and a piezo transducer, a receiver, gating pulse generators whose inputs are connected to the synchronizer, useful signal selectors, a time interval to frequency converter connected to the outputs of the latter, a counting generator a switch, a series-connected selector block, a counting block, a digital indicator, and an adjustable single-shot, the output of which is connected a selector block § The signal paths are respectively connected with each other and with the output of the frequency divider ζ, the time delay block f connected between the synchronizer output 1a 'and the input is adjustable ·? th single vibrator. £ 0 * 4 about SO