SU1335862A1 - Eddy-current flaw detector - Google Patents

Abstract

This invention relates to the field of non-destructive testing. The purpose of the invention is to increase the reliability of control by reducing: neither the effect of the gap on the parameters being monitored. The information about the monitored parameters in the form of a time interval for the establishment of oscillations of the measuring oscillator 2 is converted into a digital code and compared with the setting stored in the block 11 of the permanent memory. If the magnitude of the signal above the installation is exceeded, the indicator enable signal is generated. To compensate for the gap, the oscillation frequency of the auxiliary auto-oscillator 7 is converted into a code that serves as an address for the fixed memory unit 9, which output the correction signal for the controlled measuring auto-oscillator 2. I Il. 00 with SP 00 ate ND

Description

 one

The invention of the OTHOCPSTCH is to the field of non-destructive testing and can be used to detect defects in metal products using eddy current methods.

The purpose of the invention is to increase the reliability of control by reducing the influence of the gap on the monitored parameters.

The drawing shows a flow chart of an eddy current flaw detector.

The device contains an eddy current transducer 1 connected in series, a controlled measuring auto-oscillator 2, a transducer 3 duration — a code, a comparison circuit 4 and an indicator 5 connected in series, an eddy current transducer 6, a controlled auxiliary auto-oscillator 7, a frequency transducer 8 — code, –block 9 constant nnoy. memory and digital-to-analog converter 10, the output of which is connected to the second input of the controlled measuring auto-oscillator 2.

The device also contains the second block 11 of the permanent memory connected between the output of the frequency converter 8 code and the second input of the comparison circuit 4, and the distributor 12, the outputs of which are connected to the control inputs of the controlled measuring 2. and auxiliary 7 generators and to the converter 8 frequency code

The flaw detector works as follows.

Distributor 12 periodically turns on and off the controlled measuring auto-oscillator 2, the oscillation time of which is strongly dependent on the electromagnetic properties of the object being monitored, shown, gaps and the presence of deektov. The converter 3 duration-code forms at its output military numbers uniquely associated with the duration of the establishment of oscillations. In comparison circuit 4, the obtained value is compared with the value received from memory unit 11. If the measured value exceeds the specified value, the indicator 5 shows the signal of the defect level.

The remaining blocks are used for the sub-high sensitivity control 35862 2

of the measuring measuring oscillator 2 and work as follows.

The frequency of the controlled auxiliary auto-generator 7 depends on the gap between the eddy-current transform-i tele 6 and the product. At the output of the frequency-code converter 8, a binary code is formed of the corresponding gap size. This code serves as the address code for block 9 of the permanent memory, by which the selection of information for block 11 of the permanent memory takes place and by which

15 correction of the operation of the controlled measuring oscillator 2 using a digital-to-analog converter 10.

The installation of the converter 3 and 8 duration-code and frequency-code in the initial state is carried out according to the commands of the distributor I 2.

Claims (1)

Invention Formula 25 Eddy current flaw detector, content-. A driven controlled measurement oscillator, in the oscillatory circuit of which a first eddy current transducer is connected, connected 30 successively the comparison circuit and the indicator and the distributor, the output of which is connected to a controllable measuring oscillator, is in order. what with 35 in order to increase the reliability of control, it is equipped with a series-connected auxiliary self-oscillator, the oscillating circuit of which includes a second curved converter, and a control input connected to the output of the distributor, the frequency-code converter, the control input of which is connected to the distributor, 45 by a block of the Permanent memory and a D / A converter, the output of which is connected to a controlled measuring oscillator, a second block of permanent memory, connected between the output of the frequency-code converter and the input of the comparison circuit, and a converter-duration-code connected between the output controlled measuring oscillator and gg is the second input of the comparison circuit, and the control input of the converter duration-ko.d is connected to the distributor.