SU845084A1

SU845084A1 - Device for measuring ultrasound velocity in media

Info

Publication number: SU845084A1
Application number: SU782657596A
Authority: SU
Inventors: Владимир Антонович Худяков
Original assignee: Алтайский Научно-Исследовательский Институттехнологии Машиностроения
Priority date: 1978-08-14
Filing date: 1978-08-14
Publication date: 1981-07-07

Description

(54) ИЗМЕРИТЕЛЬ СКОРОСТИ УЛЬТРАЗВУКА В СРЕДАХ(54) ULTRASONIC SPEED METER IN ENVIRONMENTS

1one

Изобретение относитс к устройствам дл неразрушающего контрол ультразвуковыми методами и может быть использовано при исследовании физических свойств материалов.The invention relates to devices for non-destructive testing by ultrasonic methods and can be used in the study of the physical properties of materials.

Известен автоциркул ционный измеритель скорости ультразвука, содержащий последовательно соединенные стартовый генератор, генератор зондирующих импульсов , излучающий и приемный преобразователи; усилитель, селекторный блок, формирователь импульсов, выход которого подключен к входу генератора зондирующих импульсов , частотомер, ключевой каскад и ф(1рмирователь стробирующих импульсов 1There is a known autocirculation ultrasound velocity meter, which contains in series a starting generator, a probe pulse generator, and a radiating and receiving transducer; amplifier, selector unit, pulse shaper, the output of which is connected to the input of the probe pulse generator, a frequency meter, a key stage and f (1 gate of gating pulses 1

Недостатком этого устройства вл етс сложность формировател стробирующих импульсов и низка точность измерений.A disadvantage of this device is the complexity of the gating pulse shaper and the low measurement accuracy.

Известен также измеритель скорости ультразвука в средах, содержащий последовательно соединенные генератор зондирующих импульсов, излучающий преобразователь, приемный преобразователь, усилитель и селектор , триггер, выход которого соединен со вторым входом селектора, опорный генератор и частотомер 2.Also known is an ultrasound velocity meter in media containing a series-connected probe pulse generator, a radiating transducer, a receiving transducer, an amplifier and a selector, a trigger whose output is connected to the second input of the selector, a reference oscillator and a frequency meter 2.

Недостатком его вл етс низка точность измерений, обусловленна возможностью срабатывани устройства от помех.The disadvantage of it is the low accuracy of the measurements, due to the possibility of the device to respond to interference.

Целью изобретени вл етс повыщение помехоустойчивости и точности измерений.The aim of the invention is to increase the noise immunity and accuracy of measurements.

Поставленна цель достигаетс тек, что измеритель снабжен делителем частоты, вход которого соединен с выходом опорного генератора, а выход - с входом генератора зондирующих импульсов и входом триггера, последовательно соединенными 10 и включенными между выходом селектора и входом частотометра, с.хемой управлени и элементом И, второй вход которого соединен с выходом опорного генератора и вторым входом схемы управлени , второй выход последней соединен с входом опорного генератора, а выход селектора - со вторым входом триггера.The goal is achieved that the meter is equipped with a frequency divider, the input of which is connected to the output of the reference generator, and the output is connected to the input of the probe pulse generator and the trigger input, connected in series 10 and connected between the selector output and the frequencyometer input, control circuit and the AND element whose second input is connected to the output of the reference generator and the second input of the control circuit, the second output of the latter is connected to the input of the reference generator, and the output of the selector is connected to the second input of the trigger.

На чертеже представлена блок-схема измерител .The drawing shows a block diagram of the meter.

Claims

The meter contains serially connected generator .1 of probe pulses, radiating transducer 2, receiving transducer 3, amplifier 4 and selector 5, trigger 6, the output of which is connected to the second input of the selector; reference generator 7 and frequency meter 8, as well as a divider. 9 frequency, the input of which is connected to the output of the reference generator 7, and the output to the input of the generator of sounding pulses and the trigger input, sequentially connected and connected between the output of the selector 5 and the input of the frequency meter 8; control circuit 10 and element 11 whose second input is connected to the output of the reference generator 7 and the second input of the control circuit 10, the second output of the latter is connected to the input of the reference generator, and the output of the selector 5 to the second input of the trigger 6. The meter works as follows. In the search mode, the frequency of the reference oscillator 7 is increased linearly, due to the supply of a sawtooth voltage from the second output of the control circuit 10. The divider 9 divides the frequency of the reference generator 7 n times and starts the probe pulse generator. The period of the output pulses of the divider 9 is chosen to have a large damping time for the multiply reflected ultrasonic signals in the medium. Due to the radiating and receiving transducer m 2 and 3, ultrasonic vibrations are introduced into the test medium 12 and are fed as electrical signals to the input of amplifier 4. The amplified signal is fed to the first input of the pre-opened selector 5. The resolving potential to the second input of the selector is output from the trigger output 6, a divider 9 set in 1 by the output pulse. After the signal passes through the selector 5, the trigger 6 records an "O" prohibiting the passage through the noise selector. The signal passed through the selector is also fed to the input of the control circuit 10. As the pulse frequency of the generator 7 increases, there comes a moment when the signal through the generator is continuous, the signal collector coincides in time with one of the pulses of the reference generator, as a result of which the circuit 10 switches to the control voltage level storage mode The meter changes from search mode to measurements. Simultaneously, from the first output of the control circuit to the input of the element And 11, the resolving potential is applied, and the frequency meter 12 measures the frequency of the reference oscillator, corresponding to the ultrasound velocity in the medium. By searching for the magnitude of the ultrasound delay time in the medium and gating in the described meter, the possibility of a false, noisy period of auto-circulation is eliminated. Thus, the proposed meter significantly improves the noise immunity and accuracy of ultrasound velocity measurements in the medium. Claims An ultrasound velocity meter in media containing a series-connected probe pulse generator, an emitter transducer, a receiving transducer, an amplifier and a selector, a trigger whose output is connected to the second selector input, a reference oscillator and a frequency meter, characterized in that, in order to improve noise immunity and accuracy of ultrasound velocity measurements; it is equipped with a frequency divider, the input of which is connected to the output of the reference generator, and the output - to the input of the generator probing them pulses and trigger INPUT, serially connected and switched between the selector output and the frequency counter input, the control circuit and the element, the second input of which is connected to the output of the reference generator and the second input of the control circuit, the second output of the latter is connected to the input of the reference generator, and the output of the selector - with the second input of the trigger. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 503140, cl. G 01 H, 5/00, 01.22.1975.

2. USSR author's certificate No. 461362, cl. G 01 N Z9 / 04, 09.08,1973 (prototype).