SU1322137A1 - Digital eddy-current meter of conductance deviation from rated value - Google Patents

Abstract

This invention relates to the field of non-destructive testing using eddy current methods. The aim of the invention is to improve the measurement accuracy by stabilizing the excitation frequency. The device operates in two modes: the measurement mode of the electrical conductivity of the monitored product and in the mode of measuring the variation of electrical conductivity from the nominal value. In the first case, signals with a vortex are

Description

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The second converter 3 in the form of bursts of pulses goes to counter 6, and the pulses from generator 14 of the reference signal go to counter 12. After counter 6 overflows in counter 12, an exemplary number characterizing the value of conductivity is fixed and recorded in register 13. In the second mode in the counter 12 records

The invention relates to the field of non-destructive testing using eddy current methods and can be used to measure the electrical conductivity of non-ferromagnetic materials.

The aim of the invention is to improve the measurement accuracy by stabilizing the excitation frequency.

The drawing shows a block diagram of the device.

The device contains a frequency control unit 1 connected in series, an excitation signal generator 2, an eddy current transducer 3 and two former-amplifier 4 and 5

The device also contains a serially connected first counter 6 connected to the output of the amplifier maker 4, the first trigger 7, the second input of which is connected to terminal 8 Start, the second trigger 9, the clock input of which is connected to terminal 8 Start, the third trigger 10, the second input connected to the amplifier-driver 4, the first circuit And 11, the inputs of which are connected to the outputs of the amplifiers-drivers 4 and 5, the second counter 12 and the register 13, the outputs of which are connected to the data inputs of the counter 12.

The device also contains connected in series generator 14 exemplary frequency, the output of which is connected to the circuit And 11, and the circuit 15, the inputs of which created with the outputs of the shaping amplifiers 4 and 5 and the trigger 10, and the circuit 15 is connected to the counter 12,

The device also includes a trigger 16, the first input of which is connected to terminal 8 Start, and second 37

the contents of register 13 are countered, counter 6 starts counting the pulses of the measuring signal, and pulses of the reference frequency are subtracted from the contents of counter 12 before it is set to zero. After that, in the counter 6, the value of the electrical conductivity deviation from the nominal value will be recorded, 1 slug.

the swarm - with the output of the overflow of the counter 12,; and the three circuits 1SH17-19, the first inputs of which are combined and connected to the terminal 20 Mode, together

And the fifth inputs of the circuits AND 11, 15, the second inputs of the OR circuit 17, 18 are combined and connected to the Start terminal, the second input of the OR circuit 19 is connected to the overflow output of counter 6, the outputs

first and second circuits OR 17, i8

connect 1 to the input of the counter 12, and the output of the third SHS 19 circuit is connected to the setup input of the register 13,

The device operates in two modes, max: the conductivity measurement mode of the monitored product and in the conductivity measurement mode of the conductivity from the nominal value.

In the conductivity measurement mode, the device operates as follows.

A potential zero is applied to terminal 20 of the Mode and the eddy current transducer 3 is installed on the monitored product (not shown). The zero level signal arriving at terminal 8 sets the device to the initial position, translates trigger 9 into one state, which is fed to trigger information input 10, The measuring signal from the output of the amplifier -former 2 4 will switch the trigger 10, a single signal from its output will open the AND 11 circuit and the counter 12, the Counter 12 will begin to calculate the number of pulses of the reference frequency, and 6 hic number of pulses of the measuring signal. When counter 6 overflows, the signal from its output enters the register

31

13 is the measurement result of the nominal conductivity value.

When measuring the conductivity deviation by 20, a single potential is applied, the contents of register 13 are overwritten into counter 12, and counter 12 begins to subtract from the recorded number the number of pulses of exemplary frequency. Counter 6 starts counting the number of pulses of the measuring signal. When the counter 6 overflows, the counting stops and in the counter 12 there will be a number characterizing the deviation of the electrical conductivity of the product from the nominal value.

Claims (1)

Invention Formula A digital eddy-current meter for the deviation of electrical conductivity from the nominal value, containing a series-connected excitation signal generator, a eddy-current converter, and two shaping amplifiers, connected in series. the first counter connected to the output of the first amplifier maker, the first trigger, the second input of which is connected to the Start terminal, the second trigger ger, clock input of which is connected to the Start terminal of the third trigger, clock input of which is connected Or S. Patrusheva 2855/38 Compiled by Yu.Glazkov Tehred I.Popovich Cor Pod Circulation 776 VNRSHPI State Committee of the USSR for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 374 whose first amplifier is the first amplifier, the first circuit is And, the second and third inputs of which are connected to the outputs of the amplifier drivers, the second counter and the register, whose outputs are connected to the installation inputs of the second counter, connected in series to the generator of the reference frequency, the output of which is connected to the input of the first And, and the second circuit And, the inputs of which are connected to the outputs of the amplifier-shapers and the output of the third trigger, and the output of the second circuit And connected to the second counter, and the OR circuit connected between the terminal Start input of a second counter, characterized in that, in order : improve measurement accuracy, it is equipped with a frequency control unit, the output of which is connected to the excitation signal generator, a fourth trigger, the first input of which is connected to the overflow output of the second counter, and the second input is connected to the Start terminal, the second OR circuit connected between the Start terminal and the installation the input of the second counter, and the third OR circuit with terminal Re20 25 30 bench, which is connected to the fifth the inputs of the AND circuits and the second inputs of the OR circuits, and the output of the third OR circuit is connected by a JC register input. Proofreader V. But ha ha Subscription