SU1285631A1 - Versions of linear shift converter - Google Patents

Abstract

The invention relates to jc magnetostrictive linear displacement transducers with ratiometric transform. The purpose of the invention is to increase the conversion accuracy. Frequency modulated pulse digital interrogation signal at the output

Description

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The interrogator 12 is fed through the converter 9 to the input of the recording element 7 and energizes channel 2 (MK) in the magnetostrictive channel 2. ultrasound waves of modulating frequency propagating in both directions from the sources of communication. Spread to the left, the waves are scattered on the absorber 4. Spreading to the right along MK 2, the ultrasonic waves reach the reflection boundaries formed by the slider 3 of the magnet of the 1st liquid, and

having reflected, they change the direction of the stroke. At the outputs of the reading element 8 voltage modulated frequency pulses are generated due to the inverse magnetostrictive conversion. According to them, at the outputs of the analog-digital driver 13, a synchronization signal is generated, which writes the digital code into the register 17. At the output of the result calculation unit 21, a final conversion result code will be generated. 1 sec. f-ly, 3 ill.

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 1. The invention relates to the technique of measuring, testing and controlling linear transitions, namely magnetostrictive linear displacement transducers with ratiometric transformation, and can be used in automatic control systems. The purpose of the invention is to improve the accuracy of the conversion.

Figures 1 and 2 show variants of the device for transforming linear displacements with one-sided and differential transformations; on. figure 3 - timing diagram.

The linear displacement transducer of the scientific research institute (Figures 1 and 2) contains a magnetostriction linear displacement sensor 1, consisting of a magnetostricted transmission channel 2 with a magnetic slider 3 in its working cavity, an acoustic absorber 4, fixed and mobile elements 5 and 6 bias, write and read elements 7 and 8, a voltage-current converter 9, a selective reading amplifier 10, and an analog-to-digital conversion channel 11 consisting of a poll generator 12, an analog digital read driver 13, a digital switch 14, digital oscillator 15 weighted frequencies, first, second, third registers 16-18, first and second adders 19 and 20, result calculation unit 21, fourth register 22, delay element 23, block 24, synchronization, motion control unit 25, first and second input buses 26 and 27 control

f5

five

YU

, -, 35 a

25

No, the first output bit data bus 28, the second gating bus 29, the third output bit bus 30 of the motion control. In addition, the transducer (Fig. 2), in addition to the indicated features, includes an acoustic absorber 31, a biasing element 32 with writing and reading elements 33 and 34, a voltage-current converter 35, a selective reading amplifier 36, a digital-analog reading device 37 and a digital comparator 38 .

The device works as follows.

At the initial moment, the device (Fig. 1) is reset. Switching the device to the operation mode is made by lio to a digital control signal received via the first control input bus 26 to its analog-to-digital input. channel 11 conversion. This signal is used to unlock the synchronization unit 24 and start the polling generator 12 and the digital generator 15 weighted frequencies. The current digital code NJ is formed at the n-bit output of the latter, where i is the number of conversion cycles represented by a highly stable reference grid of frequencies of durations T - T, T 2 T, n 1,2 ..., where n is bit dna device. From the outputs of the digital oscillator 15 of weighted frequencies, the current digital code Nj arrives at the information inputs of the first, second and third registers 16-18 and records312

in them, using pulse digital synchronization signals generated at the second output of the polling generator 12 and the outputs of the digital switch 14 at the corresponding points in time of the current conversion cycle.

At the same time, digital p-bit codes and Nrp are set on the second input bit bus 27 of the control bus. g linear motion boundaries of the movable element 6 of the magnetization of the magnetostrictive linear displacement sensor 1, having a kinematic connection with the external object of the controlled linear displacement.

The pulse digital synchronization signal from the second output of the polling generator 12 records the current digital code of the initial conversion phase into the first register 16, which is set at the outputs of the digital generator 15 of weighted frequencies, and also block 24

sync.

At the same time (synchronously), a digital polling signal modulated in frequency is generated at the first output of the interrogation generator 12, and a voltage is applied to the input of the transducer 9 - a current installed in the housing of the magnetostrictive sensor 1 of linear displacements. arriving at the input of the fixed element 7 of the record. Below it, in the transmission magnetostriction channel 2, an ultrasonic wave of mechanical deformation modulated in frequency is excited, propagating in both directions along the magnetostrictive transmission channel of the sensor with a velocity V,

Spreading to the left (as shown in FIG. 1) through the magnetostriction channel 2 of the sensor transmission from the source of the message, the pulsed ultrasonic wave reaches the acoustic absorber 4 and dissipates its energy on it, ceasing to exist.

Spreading to the right, the ultrasonic wave passes under the immovable reading element 8 and induces in its code a frequency-modulated voltage pulse that is amplified and demodulated by a selective reading amplifier 10 installed in the case of the linear displacement 1, and

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passes from its output to the input of the analog-digital driver 13 reading the analog-digital channel 11 of the device conversion. At the output of the analogue-digital read generator 13, a pulsed digital synchronization signal is generated, which passes through the digital switch 14 to the synchronization input of the second register 17 and writes the current digital code of the initial main conversion phase into it, which is currently set at the outputs of the digital generator 15 weighted frequencies . This digital synchronization signal asynchronously starts the synchronization unit 24, the output of which generates a pulsed digital gate signal, which switches to the second state of the digital switch 14, and also generates a digital strobe signal on the second output bus 29.

Spread to the right through the magnetostrictive channel 2 of the sensor transmission, the ultrasonic wave reaches the reflection boundary formed by the magnetic slider 3 of the magnetic fluid located in the working cavity of the magnetostrictive transmission channel and held by the radial magnetostatic field of the moving biasing element 6, and having reflected, changes its direction move and at some point will re-reach the stationary reading element 8. The passage of the ultrasonic wave under the reading element 8 forms at its output a voltage pulse that passes through the selective reading amplifier 10, is demodulated, and is fed to the input of the analog-digital reading device 13. From its output, a pulsed digital synchronization signal passes through a digital switch 14 to the synchronization input of a third register 18 and writes the current digital code of the final phase of the transformation phase, which is set at the outputs of the digital generator 15 of weighted frequencies at a given time.

At the next moment, the final digital result code of the linear displacement transform is formed at the p-bit output of the result calculator 21.

Nx.i N; z.i / N ,,), (1) where N j i is a digital code generated at the outputs of the first and second adders 19 and 20, which is proportional to the resulting linear time interval generated

TKL Tg .., / T .. | where Ii Zo / V;

Tj.i 2, / V;

  zones of ratiometric and ocNoY transformation. This digital code Ny is rewritten into the fourth register 22 by a pulsed digital synchronization signal of the polling generator 12 delayed by the first output of the delay element 23. From its p-bit output, the digital code of the final conversion goes to the first output bit bus 28 of the device Data and simultaneously enters the movement control unit 25 on a pulsed synchronization digital signal delayed by the second output of the delay element 23. In block 25, the analysis of the current digital code NH of the result with respect to the specified linear motion boundaries specified by the digital codes J and Nrp.2 is performed. As a result of this analysis, the digital code Ncq.i of the position (displacement) state is formed at its t-bit output. which enters the third, output bit bus 30, controlling movement of the device.

This completes the current conversion cycle, and the device is prepared for the next conversion cycle, which starts from the moment the pulse digital is formed.

synchronization signal on the second; 45 magnetic fluids 3 of magnetic fluid located in the location of the movable bias element 6, which has a kinematic connection with the external object 50 controlled linear displacement of the device's polling generator and is performed without modification in accordance with formula (1).

The use of a magnetostrictive transmission channel with a magnetic slider from a magnetic fluid in the converter and the use of intrapulse modulation make it possible to increase the To iHocTb conversion of the linear movement into a code by increasing its noise immunity and decrease the L-offset from the center of the zone (+

nor, and, reflected from the reflection boundary, change the direction of their

move.

At times

 .

5 2 ("; ± Л) / У and Tj.i 2 (#, + 4) / V,

+ 1 ,,) linear displacement, at the outputs of the first and second elements, non-uniformly 9, these reflection boundaries with respect to the known transformation 35

calling person And the use of a contactless way of converting a linear displacement allows an increase. reduce its reliability by increasing the lifetime of 5 compared with the known converter.

In the linear displacement transducer. (Fig. 1), the relationship between the displacement direction and the final O result of the transformation takes place.

The indicated linear displacement transducer allows eliminating the marked dependence, the magnetostrictive sensor of which is made according to the differential circuit (Fig. 2).

The linear displacement transducer in a differential circuit operates as follows.

Frequency modulated pulsed digital interrogation signal on the first. Output of the interrogation generator 12 is fed through the first and second transforms.

The 9 and 35 voltage detectors are a current installed in the housing of the magnetostrictive sensor 1. of linear displacement to the inputs of the first and second elements 7 and 33 of the recording and excite the ultrasound waves of the modulating frequency propagating in the magnetostrictive channel 2 of the transmission both sides of the sources of communication on the magnetostrictive channel with speed V.

Spread left and right through the magnetostriction channel 2 of the transmission, the ultrasonic waves experience complete absorption on acoustic absorbers 4 and 31.

At the same time, spreading to the right and left through the magnetostriction channel 2 of the transmission of the sensor 1 from the sources of messages, the ultrasonic waves reach the limits of reflection,

nitric fluid located in the area of the movable bias element 6, having a kinematic connection with an external object controlled by a linear displacement where the L-offset from the center of the zone (+

where L is the offset from the center of the zone (+

nor, and, reflected from the reflection boundary, change the direction of their

where L is the offset from the center of the zone (+

move.

At times

 .

 2 ("; ± Л) / У and Tj.i 2 (#, + 4) / V,

where L is the offset from the center of the zone (+

+ 1 ,,) linear displacement at the outputs of the first and second elements

Readings 8 and 34 generate voltage pulses of the modulated frequency due to the inverse magnetostrictive transformation.

These voltage pulses at the outputs of the first and second analog-digital reading drivers 13 and 37 generate pulsed digital synchronization signals that record the current digital differential conversion codes to the second and third registers 17 and 18. The first register 16 stores the current digital code of the initial phase of the transformation, recorded in it by the pulsed digital synchronization signal on the second output of the polling generator 12.

As an n-bit output of the result calculation unit 21, the final digital result code of the linear displacement transform is generated.

N

V.i

 I N.j /Nj.il

Next, the entire conversion process fully coincides with the described conversion process for the linear displacement transducer of FIG.

Claims (2)

1. A linear displacement transducer containing a magnetostriction linear displacement transducer. Consisting of a magnetostrictive transmission channel on which an acoustic absorber is mounted and recording and reading elements with bias elements, in order to improve the accuracy of the conversion, The magnetostriction linear displacement sensor is made in the form of a tubular magnetostriction transmission channel, a moving bias element, mounted coaxially with the magnetostriction channel transmission, magnetic slider from magnetic fluid, located in the hollow of the tubular transmission channel, voltage converters - current, selective amplifier, and linear displacement transducer is equipped with an analog-digital conversion channel, consisting of a generator, a survey: analog-digital read driver, | Digital switch, digital. generation 6ra of weighted frequencies, pair, second, third and fourth registers, first and second adders, element a block for calculating the result delays, block synchronization - 5 JO 15  20 25 40 50 movement control unit, the output of the selective reading amplifier of the Magnetostriction linear displacement sensor is connected to the input of the analog-digital reading device of the analog-digital conversion channel, the output of which is connected to the input of the digital switch, the first output of which is connected to the synchronization input of the second register and the third input synchronization unit, and its second output is connected to the synchronization input of the third register, the information inputs of which are connected to the outputs of the digital generator ora of the frequencies and information inputs of the first and second registers, the outputs of the second and third registers are connected to the first inputs of the first and second adders, the second inputs of which are connected to the outputs of the first register, the outputs of the first and second adders are connected to the first and second inputs of the result calculator its outputs are connected to the information inputs of the fourth register, the synchronization input of which is connected to the first output of the delay element, and its outputs are connected to the first output bit bus and data and with the first information inputs of the motion control unit, 35 of which the second group of information inputs is connected to the second input bit bus of control, the outputs are connected to the third output bit switchboard of the motion control, and its synchronization input is connected to the second input of the delay element, the first input of which is connected to the input - synchronization of the first register, with the second the input of the synchronization unit and the second output of the polling generator, while its first output is connected to the input of the voltage converter - the current of the Magnetostrictive linear displacement sensor connected to the element ntom recording, and its control input connected to a first control input bus, a control input of the digital oscillator and the frequency-weighted with the control unit inlet sinhro55 tions whose output is connected to a digital switch with the control input and the second output line stro- birovani linear displacement transducer. 45 9 . one 2. A linear displacement transducer containing a magnetostrictive linear displacement sensor, derived from a magnetostrictive transmission channel, on which an acoustic absorber and recording and reading elements are installed with bias elements, characterized in that, in order to increase the accuracy, the magnetostrictive linear sensor Now, the displacements are made in the form of a tubular magnetostricdionic transmission channel with two acoustic absorbers at the ends, two fixed and one moving elements of the magnetisation and with the recording and reading elements installed coaxially with the magnetostrictive transmission channel, a magnetic slider from magnetic fluid located in the cavity of the tubular transmission channel, two voltage-current transducers, two selective reading amplifiers, and the linear displacement transducer is also equipped with an analog-digital conversion channel, consisting of a survey generator, the first and second analog-digital read drivers, a digital weighted frequency generator, first, second, third and fourth regis the first and second adders, the result calculation unit, the delay element, the synchronization unit, the displacement control unit, the digital comparator, the output of the first selective reading amplifier of the linear displacement magnetostrictive sensor is connected to the input of the first analog-digital reading device, and the output of the selective amplifier connected to the input of the second analog-digital read driver, the first input of the polling generator is connected to the inputs of the first and second converters; voltage — current, output per10 20 8563110 the second analog-digital reading driver is connected to the second register and the synchronization unit, and the output of the second analog-digital reading reader is connected to the third register, the information outputs of the third register are connected to the outputs of the digital frequency generator, and the outputs of the second and the third registers are connected to the first inputs of the first and second adders, the second inputs of which are connected to the outputs of the first register 5 tra, the outputs of the first and second adders with connected to the first and second inputs of the result calculator and the digital comparator inputs, which are connected to the result calculator, whose outputs are connected to the information inputs of the fourth register, whose synchronization input is connected to the first output of the delay element, and its outputs are connected to the first output bit data bus and the first information inputs of the motion control unit, in which the second group of information inputs are connected to the second input bit control bus, the highways are connected to the third output bit bus. motion control, and its synchronization output is connected to the second input 35 of the delay element, the input of which is connected to the synchronization input of the first register, with the second input of the synchronization unit and the second output of the interrogation generator, while its control input is connected to the first input control bus, to the control input of the digital weighted frequency generator and to the control input of the synchronization unit which exit is 30 45 Connie: Inen with the second bus strobe. 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