SU510081A1 - Oscillographic ferrometer - Google Patents

Description

(54) FERROMETER

A period whose output is connected to the input of the trigger 18, which divides the frequency of the following rectangular pulses into two, whose output is connected to the single-oscillator 19 via adjustable from O to T delay element 20. Single-oscillator 19 provides for the amplification of the rectangular strobe pulse through the inverting amplifier 21 with modulator 22 CRT 23 and with inputs of amplitude modulators 24-27 of instantaneous value measurement units E N, 14, number e 11,

The unit 14 for measuring instantaneous values of 3 and H includes amplitude modulators 24 and 25 channels Ne controlled by strobe pulses from amplifier 21, the output of which includes amplitude detectors 28, 29, tJ and H, connected to display devices 30 and 31 sensitive to polarities of signals and graduated in scale units of magnetization; j and Paul N.

The differential permeability and susceptibility calculation unit 11 includes amplitude modulators 26 and 27 of channels H and tJ, controlled by a strobe pulse of amplifier 21, the outputs of which are connected to amplitude detectors 32 and 33, of which the first is connected to key 34, the output of which is connected a voltage-to-time converter 35, the output of the latter is connected to one input of flip-flop 36, and the other input of which is connected to a clock generator 37. The output of flip-flop 36 is connected to the control inputs of a switch 34 and an amplitude modulator 38.

The output of the amplitude modulator 38 is connected via a filter 39 to the indicating device 30, graded in scale units JU d.

Block 12 includes an addition circuit 40 with a square 41 at the output and a subtraction circuit 42 with a square 43 at the output. Moreover, the outputs of blocks 41 and 43 are connected to the input of the subtraction circuit 44, the output of which is connected to the integrator 4S. The output of the latter is associated with the input of the display device 30, graded in scale units of total losses.

Block 15 includes a pulse generator marking axes 46, the input of which is connected to the output of the scale element 8 of channel H, and the output with serially connected frequency dividers 47 and 48 controlling the sawtooth voltage generator 49. The output of the generator 49 is connected to the inputs of circuits Comparisons 50 and 51 channels and H, the second inputs of which are connected to the inputs of the differentiator 1O of the channel and the link 8 channels N. The outputs of the comparison circuits 50 and 51 are connected to the inputs of the matching circuits 52 and 53, the second inputs of which are connected to the outputs of the trigger 54. signal m divider 48, and outputs scheme matcher 52 and 53 are connected to inputs rtravl kushimi keys 55, 56 in the channels

3 and H, the second inputs of which are connected to the output of the generator 49, the outputs of the keys 55 and 56 are connected to the inputs of the auto-switch 13, to which the outputs of the coincidence circuits are also connected. 57 and 58 channels and H, the inputs of which are connected to the outputs of the divider 47, the output of the generator 46 and the stroke of the trigger 54. The outputs of the auto switch 13 are connected to the deflecting plates 59 of the SLT 23.

Ferrometer works as follows.

The tD | c sensor signals (i and dH / di enter channels E and H, where they are corrected by phase correctors, integrated by integrators, brought to a single masiltab, and fed through a switch to the adder or directly to the differentiator. In the first case, the adder performs step 3 and The dBjdi signal is removed from the differentiator output, in the second case, the d J / df signal. The H (f) signal is converted into square pulses, triggering trigger 18, and a back-edge pulses of a given duration, with a falling edge, trigger a single-shot 19 strobe A pulse of a duration much shorter than the field, arriving at the CRT modeling electrode 22 and observing the observation point on the reversal loop induced on the CRT screen when the signals (t) and H (i) are applied through the autocommutator 13 to the E.GGT plates. 3 and H at a fixed .spKcx T with a label at the loop point is measured by calibrators, for which signals (t) to H {t) are sent to amplitude modulators of block 14, controlled by a tsazannogo strobe pulse, and detected.

At the same time, dlJ / df or / dt and dH / df signals are fed to the inputs of amplitude modulators 26 and 27, controlled by the same strobe pulse, and detected by amplitude detectors 32, 33. To calculate the differential susceptibility by dividing these signals at a given point

U (d3 / di) dJ TTTuH / dt cpt d

Claims (3)

a clock oscillator of rectangular pulses of a period T 37 tilts the trigger 36, which opens the key 34 and the amplitude -. The modulator 38 and the converter 35 receive a signal from the H channel detector which it converts to a time interval t ifuCdH / diJB the end of which the converter generates a short pulse returning the trigger 36 to the initial position at which the key 34 and the modulator 38 are locked and so on. d. At the output of the amplitude modulator 38, a sequence of pulses of duration t and period T has an amplitude and (, and its mean value (d3 / dt.) Is t -U () tpV tKclH / di) where is the scale factor. The signal from the filter 39 of nonzero frequencies is fed to the display device 30, to accurately measure the coercive force, the H mark is re-entered into a position in which the differential susceptibility of the Bone reaches its maximum and pokes on the device 31. For accurate measurement of the residual magnetization f or H the period of the frequency of the magnetizing field switches the phase of the H signal. As a result, a combined image of a remagnetization loop is induced on the CRT screen. and its mirror image about axis 3. The bright label is fixed at the intersection points of the branches of these pegel and tJ-b is counted on the device 30. Simultaneously, the demagnetization of the measured samples is monitored by symmetry about the H axis of the differential susceptibility at the central symmetric points of the loop. To calculate the total loss of the signal, dT | dt or dB / dt and H ({) go to the inputs of the readout circuit and the block 12 in which the output of the readout circuit 44 is implemented (dJ + H) - (dJ -H) 4H ctJ, and at the output of the integrator, the signal is U 4oSH, where K p is the scale loss factor; P - total loss. By the loss calculation unit 12, the device is certified by a reference sample certified by the State Standard for full losses Р in saturation mode 3 f when a constant loss level of 30 is reached. The brightness label leads to the loop top and the indicating device is graduated by Dm D direct documentation of the measured samples by reproducing the image of the magnetization reversal loop and decreasing the reference errors due to nonlinear distortions introduced by the CRT and thereby increasing the In order to use the screen, a block of indication of calibrated labeled coordinate axes is inserted, operating as follows. The generator of short pulses of the scale mark of the axes 46, synchronized with the signal H, the frequency of which is divided twice in the ratio of 1:10 by dividers 47 and 48, sets the duration of the sawtooth pulses of the generator 49. The amplitude of the sawtooth voltage of the generator 49 is limited to values equal to the amplitudes of the signals H - and tJ g, by means of comparison circuits 50 and 51, the signals from the output of which through the clock are opened by the keys 55 and 56 using the matching circuits 52 and 53, the second inputs of which are supplied with clock amplitudes from the trigger 54, controlled by the signals c divider 48 generator of scale marking of axes. Pilo-phase signals from the keys, having amplitudes H f and 3 m, are fed to the auto-switch 13, which, after a period of a magnetizing field, supplies the CRT plates with a string of signals with the signals H (i:) and {i}. The imposition of scale mark pulses from generator 46 and divider 47 form scale scales, which are supplied by coincidence circuits 57 and 58 to deflection plates at clock intervals between the passage of sawtooth voltages, thus ensuring uniformity of the images of the loop, axes and decimal marks. Claim 1. Ferrometer for oscillographic measurement of magnetic characteristics of core samples of hard magnetic materials according to ed. By 192937, characterized in that, in order to increase accuracy and speed, it is equipped with a gating converter, an instantaneous value converter and H to a constant voltage, a unit for calculating differential magnetic permeability and susceptibility, a unit for calculating total losses, and a unit for forming scale-marked coordinate axes 3 and H, a differentiator and an auto-switch with a phase switch of the H channel, the gate of the converter being connected to the output of the scale link of the H channel, and the output from the modules The CRT electrode and amplitude modulators of the instantaneous values tJ and H conversion unit and the jUg calculation unit or the instantaneous value converter inputs are connected to the outputs of the scale link of the H channel and the integrator or the channel adder Tj the inputs of the calculator ju are connected to the inputs of the H channel integrator and the output the channel differentiator t3 inputs of the loss computation unit are connected to the outputs of the channel differentiator and the scale even of the channel H; and the outputs of these blocks are connected with the appropriate calibrators, scaled in the scale units of magnetic quantities; the input unit forming the axes J and I is connected to the outputs of the scale link of the channel H and the differentiator of channel 3, and the output with the plates of a CRT through an auto switch, the input of which is connected to the output of the scale link of the channel N. 2. A ferrometer according to claim 1, characterized in that the strobe converter is equipped with an inverting amplifier connected to the instantaneous value converter and H modulator, and the input 5 1® is connected to the strobe pulse former, 3. A ferrometer according to claim 1, characterized in that the block forming the calibrated axes includes a generator of pulses of the scale mark, the input of which is connected to the output of the scale link of channel H, and the output is connected to successive scale, for example decimal, frequency dividers connected to the generator sawtooth voltage, and the output of the latter is connected to the inputs of the comparison circuits 3 and H, the second inputs of which are connected to the input of the differentiator channel 3 and the output of the scale link of the channel H, and the outputs of the comparison circuits are connected with matching schemes, keys in channels 3 and H, and a trigger, and the outputs of the keys with the input of the auto switch. J2j