SU1249328A1 - Ultrasonic device for measuring thickness - Google Patents

Abstract

The invention relates to a measurement technique and can be used in measuring the waveform. The aim of the invention is to improve the measurement accuracy by eliminating the instability of the generator on time. In an ultrasonic device for measuring the thickness of moving objects, the combined transducers of the first and second measuring channels sound the test item from two sides. The combined converter of the compensation channel is voiced by the reflector. The time of the measuring unit measures the number of pulses proportional to the sum of the propagation time of acoustic pulses from the combined transducers to the controlled product and back to the nerve and the second measuring channels and the time difference of the propagation of acoustic pulses from the combined transducer of the compensation channel to the reflector and back. 2 Il. (L to; oo to 00

Description

This invention relates to a measurement technique and can be used to measure thickness.

The purpose of the invention is to improve the measurement accuracy by eliminating the instability of the generator on time.

FIG. 1 shows a block diagram of an ultrasonic device for measuring the toli of moving objects; in fig. 2 is a block diagram of the time of the measuring unit.

The ultrasonic thickness measuring device contains the first 1 and second 2 measuring channels, each of which consists of a series-connected combined transducer 3 (4) and a selective amplifier 5 (6).

scaled converters 3 and 4 of the first 1 and second 2 measuring channels, and the distance between the combined converters 3 and 4 of the first 1 and second 2 of the measuring channels is equal to the distance 5 between the combined converter 8 of the compensation measuring channel 7 and the reflector 9 The switching unit 25 is provided for switching between the output of the first generator 12 and the inputs

Q first 22, second 23 and third 24 single-oscillators, as well as the inclusion of the key 26 between the input and output of the conversion unit 25.

Ultrasonic device for measuring the thickness of moving objects Work Compensation channel 7, made 5 em as follows, in the form of serially connected together-Operating in autogeneration mode

With the transducer 8 with the reflector 9, the first generator 12 excites simultaneously the selective amplifier 10, the time is measured by three combined transducers 3,

The unit is 11, the first input of which is co-4 and 8 of the first 1, second 2 and is compensated with the output of the selective 6th 7 channel. The emitted pulses of the second measuring channel 2, second propagated in the medium, reach the surface of the tested product from different sides, are reflected from it and re-enter the corresponding combined transducers 3 and 4, exciting an electric pulse. These pulses are amplified, formed by selective amplifiers 5 and 6, and supplied to the first and third inputs of the time of the measuring unit 11, to the fourth input of which a pulse is also output from the output of the first generator 12. Radiated channel 2 is connected to the output of the first 30 combined generator 12. generator of acoustic acoustical impulse spreading to

The time measuring unit 11 is designed as an EiTOporo generator 13, the first 14 and second 15 triggers, the first inputs of the co-input - with the output of the selective amplifier

10 of the compensation channel 7, the first generator 12, the output of which is connected to the inputs of the combined transducers 3 and 8 of the first and compensation channels 1 and 7.

The third input is the time of the measuring unit

11 is connected to the output of the intelligent amplifier 5 of the first channel 1, the input of the combined converter 4 of the second meter is connected

selective outputs

environment, reaches the surface of the reflector 9, is reflected from it and re-enters the combined converter 8 of the compensation channel, exciting the silytel 6 element of the second channel 2 and the selective 35 pulse that is amplified and the second amplifier 10 of the compensation channel 7 is formed by the selective amplifier 10 and

series-connected logical input to the second time input - the measurement element OR 12, the inputs of which are the connecting block 11 (Fig. 2).

The first and second triggers 14 and 15 of the forstate pulse pulses, the duration of which is equal to the time of propagation of acoustic pulses from the combined transducers 3 and 4 of the first 1 and second 2 measuring channels to the test item and vice versa. The third flip-flop 20 of the Andy element 21, the output of which is connected to 45 em pulses, the duration of which is equal to the second input of the reversing counter 18, the propagation time of the acoustic

impulse from the combined converter 8 to the reflector 9 and back is compensated with the outputs of the first 14 and second 15 triggers, the first logic element AND 17, the reversing counter 18 and the indicator 19 connected in series to the third trigger 20, the first input of which is connected to the output of the selective amplifier 5 of the first channel 1 and second logical

the first 22, second 23 and third 24 single-vibrators, the inputs of which are connected to the output of the first generator 12, the outputs, respectively, with the second input of the indicator 19, with the third and fourth inputs of the reversing counter 18. The second inputs of the first 14, second 15 and third 20 triggers connected to the outputs of the first generator 12, and the second inputs of logic elements

50

7. The pulses from the outputs of the first 14 and second 15 triggers are fed to the input of the logical element OR 16, from the output of which the signals arrive at the first input of the first logical element And 17, the second input of which receives the pulses from the output of the second generator 13. and 21 are connected to the outputs of the second output input of the reversible counter 18 of the post-generator 13. pulses are output from the first logical unit. There is a provision to install a monitored product (not labeled) between the And 17 element, and to the second input - pulses from the output of the second logical logic units with converters 3 and 4 of the first 1 and second 2 measuring channels, and the distance between the combined converters 3 and 4 of the first 1 and second 2 of the measuring channels is equal to the distance between the combined converter 8 of the compensation measuring channel 7 and the reflector 9. Provision is made for the switching unit 25 between the output of the first generator 12 and the inputs

the first 22, the second 23, and the third 24 single-oscillators, as well as the inclusion of the key 26 between the input and output of the conversion unit 25.

Ultrasonic device for measuring the thickness of moving objects

7. The pulses from the outputs of the first 14 and second 15 triggers are fed to the input of an OR 16 gate, the output of which sends signals to the first input of the first AND 17 gate, to the second input of which pulses come from the output of the second generator 13. To the first input the reversing counter 18 receives impulses from the output of the first logical input of the reversible counter 18, impulses from the output of the first logical element I 17, and to its second input - pulses from the output of the second logical element I 21, to the nerve input Secondly, signals are output from the third trigger 20, and to the second - from the second generator 13. Reversible counter 8 records the number of pulses proportional to the sum of the propagation time of the acoustic pulse from the combined transducers 3 and 4 to the tested product and back to the first 1 and second 2 measurement channels and the time difference between the propagation of acoustic pulses from the combined converter 8 of the compensation channel to the reflector 9 and vice versa. For controlling the time, the measuring unit 11 is the counting unit 25, a key. 26 and three one-shot 22-24 pulses with a duration slightly less than the period following the first generator 12. The falling edge of the pulse generated by the one-shot 22 clears the previous indicators of indicator 19. The falling edge of the pulse generated by the one-shot 23 causes the resolution of the reversal counter 18 to be thrown the indicator 19, the falling edge of the pulse generated by the single vibrator 24, is reset to the reversible counter. If it is necessary to average readings from 10 or 100 measurements, the key 26 opens, shunting the scaler 25, and the one-shot 22-24 are triggered by every 10th or 100th pulse (depending on the conversion factor).

Claims (1)

Invention Formula Ultrasonic device for measuring the thickness, containing the first and second measuring channels, each made in the form of a series-connected combined transducer and a selective amplifier, a compensation channel made in the form of a series-connected combined transducer with a reflector and a selective amplifier, the time of the measuring unit, the first the input of which is connected to the output of the selective amplifier of the second measuring channel, the second input - to the output of the selective amplifier compensating channel, the first generator, the output of which is connected to the inputs of the combined transducers of the first measuring and compensation channels, characterized in that, in order to improve accuracy, the third input time of the measuring unit is connected to the output of the selective amplifier of the first measuring channel, the input of the combined transducer of the second channel is connected to the output the first generator, while the measuring unit is designed as a second generator, the first and second triggers, the first inputs of which are connected to the outputs amplifiers of the second measuring and compensation channels, connected in series OR logic element, whose inputs are connected. to the outputs of the first and second flip-flops, the first logic element AND, a reversible counter and indicator connected in series to the third flip-flop, the first input of which is connected to the output of the selective amplifier of the first measuring channel, and the second logical element And, the output of which is connected to the second input of the reversible counter, the first, second and third one-shot, the inputs of which are connected to the output of the first generator, and the outputs, respectively, with the second input of the indicator, with the third and fourth inputs of the reversible counter, the second inputs of the first, second and third triggers are connected to the output of the first generator, and the second inputs of logic gates And are connected to the output of the second generator . (DU2.2