SU1527483A1 - Device for converting linear displacements into frequency - Google Patents

Abstract

The invention relates to a measurement technique and permits an increase in the accuracy of converting linear displacements into frequency by compensating for the effects of external magnetic fields. In the device containing measles 1, P - shaped magnetic core 2, input winding 3, sensor 4 nuclear magnetic resonance, amplifier 6, filter 8, driver 10, current generator 14, input source 17, sensor 5, amplifier 7, filter added 9, driver 11, element OR 12, frequency divider 13, one-shot 15, 16. When external magnetic fields are applied to a U-shaped magnetic circuit 2, the magnetic field increases in one of the rods and decreases in a second one by a certain amount B, hence the frequency of the pulses on one of the entrances OR gate 12 is reduced by the amount of F / B /, and the other is incremented by F / B /. Considering the frequency at the inputs of the element OR 12, corresponding to a magnetic field without interference, equal to F / A /, at the output of the element OR 12 we get: F = (F (A) + F (B)) + (F (A) -F (B )) = 2F (A). At the output of the divider 13 frequency receive frequency F / A /, proportional to the linear movement of the core 1. 1 Il.

Description

one

(21) 4330942 / 24-28

(22) 11/18/87

(46) 12/07/89. Bul Number 45

(72) A.V. Abramushkin and A.V. Levitsky

(53) 621.317.39: 531.717 (088.8)

(56) USSR Author's Certificate No. 1404801, cl. G 01 B 7/00, 1986.

(54) DEVICE FOR TRANSFORMING LINEAR DISPLACEMENTS TO FREQUENCY

(57) The invention relates to a measurement technique and makes it possible to improve the accuracy of converting linear displacements into frequency by compensating for the effects of external magnetic fields. In the device containing measles 1, U-shaped magnetic core

2, input winding 3, nuclear magnetic resonance sensor 4, amplifier 6, filter 8, driver 10, current generator 14, input source 17, sensor 5, amplifier 7, filter 9, driver 11, element OR 12, divider 13 are added frequencies, one-shot 15, 16. When external magnetic fields are applied to a U-shaped magnetic circuit 2 in one of the rods, the magnetic field increases and in the other decreases by a certain amount B, therefore, the frequency of the pulses at one of the inputs of the OR 12 element decreases by f (B), and on the other m is increased by f (B). Considering the frequency at the inputs of the element OR 12, corresponding to a magnetic field without interference, equal to f (A), at the output of the element OR 12, we get F «(f (A) + f (B)) + (f (A) -f ( B)) - 2f (A). At the output of the divider 13, frequencies are obtained frequency f (A), which is proportional to the linear movement of the core 1. 1 Il.

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The invention relates to a measurement technique and can be used to measure linear displacements.

The purpose of the invention is to improve the accuracy of transformations by compensating for the effects of external magnetic fields.

The drawing shows the block diagram of the device.

The device contains measles 1, P-shaped magnetic core 2, input winding 3, sensors 4 and 5 nuclear magnetic resonance, amplifiers 6 and 7, filters 8 and 9, drivers 10 and 11, element OR 12, frequency divider 13, current generator 14, one-shot 15 and 16, the source 17 of the input signal.

The input winding 3 is located on the jumper of the U-shaped magnetic circuit 2. Sensor 4 is located in the section of the first rod of magnetic circuit 2, sensor 5 is located in the section of the second rod, sensor 4 output is connected via i connected in series amplifier 6, filter I, shaper 10, one-shot 15 to the first input of the element OR 12, the output of sensor 5 is connected in a similar way via a sequential amplifier 7 filter 9, driver 11, one-shot 16 to the second input of the element OR 12, the output of the element OR 12 is connected to the input of the divider 13 hour plots, the output of the generator 14 current is connected to the sensor inputs 4 and 5.

A device for converting linear displacements into frequency by working as follows.

A stabilized voltage from source 17 is fed to the input winding 3, as a result of which a magnetic field is generated in the magnetic circuit 2 and in sensors 4 and 5. Using a current generator 14 in sensors 4 and 5, an auxiliary magnetic field is induced for a short time, after which a precession of the field occurs, sensors 4 and 5 remove the nuclear induction signal with a frequency proportional to the values of the magnetic fields in the corresponding rods of the magnetic circuit 2. Signals the first sensor 4 is amplified by the amplifier biv to the filter 8, it is separated from the noise by a block; with the block 10, a sequence and 1 pulses of a wave are generated from the voltage of a sinusoidal damping waveform of nuclear induction

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of the same fronts of which receive at the output of a single-vibrator 15 short pulses. The frequency of the obtained sequence of these pulses is proportional to the magnitude of the magnetic field in the first core of the magnetic circuit 2. Similarly, the nuclear induction signal from sensor 5 is removed and processed by amplifier 7, filter 9, driver 11 and single-axis 16. At the output of the frequency element OR 12, the resulting sequence of pulses serves to the input of the divider frequency 13. Changing the position of the core 1 changes the magnitude of the magnetic resistance in the gap between the core 1 and the rods of the magnetic circuit 2, and hence the magnitude of the magnetic field in the rods of the magnetic circuit 2, as a result of which the frequency of the pulses at the output of the formers 6 and 7 changes, in block 12 these the frequencies are summed, and in the divider 13, the frequencies are divided by 2, as a result, at the output of the element OR 12, we obtain a frequency proportional to the magnitude of the linear movement of the core 1. When exposed to external magnetic fields on the U-shaped magnetic circuit 2 in one of the rods In this case, the magnetic field increases, while in the other it decreases by a certain magnitude B. Therefore, the frequency of the pulses at one of the inputs of the OR element 12 decreases by f (B), and at the other increases by f (B), receiving a magnetic field without external magnetic fields in the magnetic circuit 2 for A and the corresponding frequency at the inputs of the mixer 12 for f (A), we have the frequency at the output of the element OR 12

F (f (A) + f (B)) + (f (A) -f (B)) 2f (A).

Thus, by dividing this frequency by a divider 13 frequency by 2, receive a frequency proportional to the linear movement of the core 1.

Claims (1)

Invention Formula A device for converting linear displacements into a frequency containing measles, U-shaped magnetic core, input winding, input source, current generator, first nuclear magnetic resonance sensor, first amplifier, first filter and first driver, input winding is located on P shaped: - 51527483 the first conductor of the turf second shaper, two single-magnetic resonance is located the second, the OR element and the divider is a partial section of the first rod of the U-shaped, the second sensor of the nuclear magnetic field, the output of the generator of the resonance is in the section ka through a serially connected second rod of a U-shaped magnetic first sensor of nuclear magnetic wire, output current generator resonance, the first amplifier, first through a series connected The filter is connected to the input of the first nuclear magnetic sensor. shaper, inputs of an input-resonance source, second amplifier, second The signal is connected to the filter pins, the second driver and the primary winding, which distinguishes the one-shot vibrator connected to the first one, in order to increase the input element of the OR element, which by connecting external magnets to the input of the splitter frequency splitter, into the black The second f5Ts are introduced, the output of the first generator of the nuclear magnetic resonance-cut second second one-shot is connected ca, second amplifier, second filter, to the second input of the element OR.