SU1305590A1 - Device for flaw detection of ferromagnetic articles - Google Patents

Abstract

The invention relates to the field of non-destructive testing and can be used to detect defects in ferromagnetic products with an untreated complex surface. The aim of the invention is to increase the effectiveness of control by automating the tuning process and limiting its cycle. The generator 2 excites a vortex converter 3, the signals from which are fed to the detector 4 and the phase meter 8. When the distance between the eddy current transducer and the monitored product changes, the comparators 23 and 24 form a control pulse for the memory cell 11, at which moment the memory cell remembers input voltage. In the event that the signal from the detector 4 changes at this time, the differential amplifier 12 amplifies the difference signal by switching the reversible counter 19 to complex & (L co o JV ate with

Description

or subtraction. The signal from the counter is converted to analog value and controls the frequency of oscillator 2 by adjusting it to those

one

The invention relates to non-destructive testing of materials and products and can be used to detect defects in ferromagnetic products with an untreated, complex surface.

The purpose of the invention is to increase the efficiency of control by automating the tuning process and limiting its cycle.

The drawing shows a block diagram of the device.

The device contains a voltage source 1 connected in series, generator 2, eddy current transducer 3, detector 4, signal gain analysis unit 5 and indicator 6, control unit 7 connected to the second input of cycle increment analysis unit 5, phase meter 8 connected between generator outputs 2 and the eddy current transducer 3 and the second input of the signal increment analysis unit 5, the tuning unit 9 connected between the output of the detector 4 and the control input of the generator 2, and the tuning cycle limiter 10 connected between the output ode phase meter 8 and the second input unit 9 settings.

The tuning unit 9 comprises a memory cell 11 connected in series, a differential amplifier 12, the second input of which is combined with the memory cell input 11, a forward and backward counting generator 13, an OR 14 circuit and a zero indicator 15, and a series 16 counting generator connected in series pulses, two circuits And 17 and 18, the second inputs of which are connected to the output of the imaging unit 13 direct and reverse counting, reversible counter 19 and digital-to-analog converter 20 ..

The limiter 10 tuning cycle contains two sources 21 and 22 of the reference voltage, two comparator

until the voltage at the inputs of the differential amplifier is matched, i.e. the amplitude of the signal will not change. 1 il.

23 and 24, the first inputs of which are connected to the respective sources 21 and 22 of the reference voltage, and the second inputs are combined and are the input

limiter 10 of the tuning cycle, two formers 25 and 26 and trigger 27, whose inputs through the formers 25 and 26 are connected to comparators 23 and 24, and the output is the output of limiter 10 for the tuning cycle and is connected to the memory cell 11.

The device works as follows.

The generator 2 excites a vortex converter with a frequency determined by the source 1 of the reference voltage. The information signal is fed to the detector 4 and simultaneously to the phase meter 8, where the amplitude and phase characteristic of the signal are separated.

The signal from the output of the phase meter 8 is supplied to the comparators 23 and 24 and through the formers 25 and 26 to the trigger 27,

As the eddy current transducer 3 is retracted from the part being monitored (not shown), the signal decreases, which causes the comparators 23 and 24 to operate sequentially, and consequently, the trigger 27, which controls the operation of the cell, switches. 11 memories.

With a zero signal at its control input; The memory cell 11 exerts a voltage repeater function, and the setting unit 9 does not work. With a single signal, the memory cell remembers the signal magnitude and if a signal changes during this time, a signal will appear at the output of the differential amplifier 12 that will cause the formation of pulses at the outputs of the normalizer 13 forward and reverse counting. This signal will open the circuits of And 17 and 18, and the pulses from the generator 16 of the counting pulses are sent to the reversible counter 19, measuring

31305590

its state and, therefore, the voltage at the output of the analog-to-digital converter 20, which buoses the oscillator frequency 2 until the signal level at the differential amplifier 12 is equal to zero. This state is indicated by a null indicator 13.

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Claims (1)

Invention Formula A flaw detection device for ferromagnetic products containing a generator connected in series, a eddy current transducer, a detector, a signal increment analyzer and an indicator, a control unit connected to the second input of the signal increment analyzer, and a phase meter connected between the generator and the eddy current transducer outputs and the third input of the unit analysis of signal increments, different connected between the detector output and the second control input of the generator and consisting of a serially connected memory cell, a differential amplifier, the second input of which is combined with the input of the memory cell, a forward and reverse counting circuit, an OR and zero-organ circuit, and connected in series a counting pulse generator, two 2I circuits, the second inputs of which are connected to the forward and reverse counting drivers, a reversible counter and a digital-to-analog converter, and a tuning cycle limiter enabled Between the output of the phase meter and the control input of the memory cell, consisting of two sources of reference voltage, two comparators, the first inputs of which are combined and are the input of the limiter of the tuning cycle, and the second inputs are connected to the sources of reference voltage, two drivers and trigger so that, in order to increase the monitoring efficiency, it is equipped with source and -25 control inputs of which are connected by a reference voltage, connected via drivers to the output to the generator, tuner, comparators. Compiled by Yu. Glazkov Editor A, Kozoriz Tehred M. Khodanych Proofreader L. Pilipenko 1423/42 Circulation 777 Subscription VNISTI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 connected between the detector output and the second control input of the generator and consisting of a serially connected memory cell, a differential amplifier, the second input of which is combined with the input of the memory cell, a forward and reverse counting circuit, an OR and zero-organ circuit, and connected in series counting pulse generator, two 2I circuits, the second inputs of which are connected to a forward and reverse counting drivers, a reversible counter and a digital-to-analog converter, and a tuning cycle limiter enabled Between the output of the phase meter and the control input of the memory cell, consisting of two sources of reference voltage, two comparators, the first inputs of which are combined and are the input of the limiter of the tuning cycle, and the second inputs are connected to the sources of reference voltage, two drivers and trigger the control inputs of which are connected via drivers to the outputs of the comparators.