SU1619400A1 - Magnetostriction displacement converter - Google Patents

Abstract

The invention relates to automation and computing and can be used to convert information about linear and angular movements into analog and digital forms. The aim of the invention is to increase the accuracy, simplify the transducer and expand its field of application. To do this, the E magnetostrictive displacement transducer, containing a waveguide 1 made of magnetostrictive material, reflective surfaces 2, an electroacoustic transducer 3, a fattening device 4 pulses, a recording amplifier 5, a reading amplifier 6 and a comparator 8, introduced a single vibrator 7 and 9 and a time interval converter . This goal is achieved due to the fact that a wild electroacoustic transducer 3 is used, as well as by reducing the error caused by the effect of multiply reflected acoustic pulses in waveguide 1 and forming information at the output both in digital and analog form. 2 hp f-ly, 2 ill. (L & amp & amp & 4

Description

The invention relates to automation and computing and can be used to convert information about linear and angular movements into analog and digital forms.

The purpose of the invention is to improve accuracy, simplify the converter and expand the scope of its application.

Figure 1 shows the structural scheme of the magnetostrictive displacement transducer; in fig. 2 - time diagrams of currents and voltages, which describe the operation of the converter.

The magnetostrictive displacement transducer contains a waveguide 1 made of a magnetostrictive material, reflective surfaces 2, an electroacoustic transducer 3, a shaper 4 pulses, a recording amplifier 5, a read amplifier 6, one comparators vibrator 7, a single vibrator 9, a 10 time converter, which is made in the form of a shaper And pulses, integrator 12, comparator 13, and lowpass filter 14.

Magnetostrictive displacement transducer works as follows.

When the device is turned on, there are no acoustic pulses in waveguide 1, as a result of which read pulses are also absent and no zero M R input of one-oscillator 9 pulses from the output of comparator 8 are received. In this case, one vibrator 9 produces pulses

U0 (FIG. 2), having the longest duration C06cr indicated on the Uq diagram with a dashed line. The duration T9 C05 (HGb is determined solely by the parameters of the RC circuit of the one-oscillator 9 and is chosen to be longer than the maximum value of the propagation time of the acoustic pulse through the waveguide 1. Of these pulses, the driver 11 of the input integrating signal generates an input current for the integrator 12, the output of which is U ° a (Fig. 2) linearly increases over the time TcSBOTB of the pulse Ug existence and decreases linearly to zero level over time to Tg, where the coefficient K shows the ratio of the charge current l | 4 to the discharge current yes, and is set by the parameters of the converter 10 time intervals

0

five

0

five

0

five

0

5 Q 5

(figure 1). The comparator 13 captures the moments when the voltage U (Fig. 2) reaches zero, and the pulses U, from the output of the comparator 13, restart the one-oscillator 9 (Fig, 1) and re-excite the acoustic pulse in waveguide 1 through the driver 4 and the recording amplifier 5. The presence at the outputs of the device of the values and 2tzhdi T (Eta1 ((sovstv)) (Fig.2) indicates the absence of a readable acoustic pulse U6, which occurs in the event of a malfunction or at the location of the electroacoustic transducer 3 (Fig.1) in the inactive zone of the waveguide 1, t i.e. outside the permissible conversion zone of the input angular displacements In normal mode, the permissible zone of the input displacements of the UFDD magnetostrictive displacement transducer works as follows: Under the influence of a pulse Uq. (Figure 2) an electrical recording pulse Uj is excited, converted by means of an electro-acoustic transducer 3 Fig. 1) into an acoustic pulse propagating in waveguide 1 at a constant speed from an excitation point in opposite directions to the end surfaces of 2 waves 1 water from which the reflection occurs. The reflected acoustic pulses return back to the excitation point after a time

v§-24 "t- {f

C is the speed of propagation of the acoustic pulse through waveguide 1; R is the waveguide radius 1; tp - input angular displacement (measured between the end of the waveguide 1 and the electro-acoustic transducer 3). At the same point, by means of the inverse electro-acoustic conversion, the same transducer 3 reads the delayed electric pulse U6 (Fig. 2), and the moment of fixation of the pulse Ug is produced according to the value Unfl0 by the comparator 8

2 () where

(fig.l)

In tension

U,

jg at the output of the readout amplifier 6, along with the readable delayed in waveguide 1

m

and

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waveguide 1 at the time of the V-zolol hL k

M J t i Jt 2

a pulse at the beginning of each cycle is also present and a large amplitude disturbance impulse, which is a recording pulse and a decaying process.

516

from the effect of the latter in the winding of an electroacoustic converter 3 with a duration of 2.5-4 μs. In order to avoid the comparator 8 triggering from interference for the duration of its operation, the comparator 8 is locked by sending a prohibition signal to its gate input from the inverse output of the one-vibrator 7, which is triggered by pulses AND from the output of the converter 10; at the same time, the duration of the U pulses produced by the single vibrator 7 is set slightly longer than the duration of the interference from the write pulse (i.e. 4.5-5 μs).

The first of the series of recorded read pulses UQ (Lig.2), delayed by the time h, - 2 CP, postuo

It goes to the installation input of the one-shot 9 (Fig, 1) and produces a breakdown of its own pulses, shown by a dotted line on the UQ diagram (Figure 2). The moments of failure, shown by the arrows Ч between the Ug and Un diagrams, determine the duration Ta of pulses U, which depends linearly on the input angular displacement (0, the same duration is given by 1 ″ charging current pulses, which are the input signal for integrator 12 (FIG. 1), and at this time Ј (C () 3 at the output of the integrator 12, a linear increase in voltage occurs (Fig. 2). After the termination of the pulse U and a discharge occurs in K times lower than the current UK and the linearly decreasing voltage U at the output de integrator 12 (FIG. 1) reaches zero level fixed by the comparato rum 13, through time (K + 1) T9 () after the start moment.From the output of the comparator 13, pulses (figure 2) are sent to a recurrent excitation of an acoustic pulse in waveguide 1 (figure 1) through shaper 4 and amplifier 5 records and also for restarting of monovibrators 7 and 9 (explained by the arrows between the U and UQ diagrams in Fig. 2). The length T is different (in the left and right parts of the diagrams (Fig. 2) it illustrates the operation of the magnetostriction displacement transducer using the example of two different values of input displacement Cfx sov U outputted from the transducer is an information parameter which is linearly dependent on the input movement

06

and is easily represented in digital form, and the constant component of the voltage Uvi, taken from the output of the integrator 12 (AIG.1), allocated by the Ailtra 14 low frequencies at the output by voltage, also linearly depends on the input displacement Cf and is convenient for analog representation of the conversion result.

Claims (3)

1. A magnetostrictive displacement transducer containing a waveguide, made of a magnetostrictive material, an electroacoustic transducer mounted against a waveguide that is connected to the input a read amplifier, the output of which is connected to the first analog input of a comparator, a write amplifier, characterized in that, in order to improve the accuracy and simplify the converter, two single vibrators are introduced into it, Force pulse, time converter and reflecting surfaces that are located on the ends waveguide output pulse generator is connected to the input of the recording amplifier, the output of which is connected to the electroacoustic converter, the second analogue input of the comparator is connected to the bus the reference voltage, and the output — to the installation input of the first one-oscillator, the output of which is connected to the input of the time converter, the output of which is the pulse output of the converter and connected to the input of the pulse shaper, the start input of the first one-oscillator and the start input of the second one. the output of which is connected with an aetrating comparator input. 2. The converter according to claim. Characterized in that the time converter is made in the form of a pulse shaper, an integrator and a comparator, the input of the pulse shaper is the input of the converter, and the output is connected to the integrator's input, the output of which connected to the first input of the comparator, the second input of which is connected to the common bus, and the output is the output of the time converter 3. Converter on PP. 1 and 2, characterized in that, in order to expand the scope of application of the converter, a low-pass filter is inserted into it, the input of which is connected to the integrator output of converters (coScmB) 6194008 time range generator, and the output of the low-pass filter is the analog output of the magnetostrictive displacement converter S J Research Institute Bootstrap or run cycles without a read signal Ug