SU1657968A1 - Electromagnetic level meter - Google Patents

Abstract

The invention relates to instrumentation engineering, and permits an increase in the accuracy of measurement of the level of aggressive and explosive liquids. At the output of the direct current amplifier 9, an increasing signal is formed, due to which the magnetic field of the electromagnet 8 increases. After the ejecting force of the liquid and the force of interaction of the magnetic field of the electromagnet 8 with the core 3 total exceeds the force of gravity of the cylindrical float 1, the latter will pop up . In this case, the buoyancy force is a function of the code at the information output of the counter 12, through which the signal is formed at the output of the DC amplifier 9. 1 il.

Description

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The invention relates to instrument making and is intended to control the level of aggressive and explosive liquids under pressure other than normal.

The aim of the invention is to improve the measurement accuracy.

The drawing shows the block diagram of the proposed electromagnetic level gauge.

The level gauge contains a cylindrical float 1 with negative buoyancy, at the bottom of which there is a permanent magnet 2, and in the upper part there is a core 3 of magnetic material. The cylindrical float 1 is suspended by means of two strands 4 and 5 to a flange 7 mounted on a controlled volume 6, on which an electromagnet 8 is attached, connected to the output of a DC amplifier 9. The amplifier 9 is connected to its input with an output of a digital-to-analog converter 10 connected to the information outputs of a binary counter 12 connected to the installation input together with the recording input of the random access memory 11 to the first and second outputs of timer 13. The latter is connected to the start input to the output of the static trigger 14 together with the first input of the element OR 15, connected by its output with the counting input of the binary counter 12, and the second input through the frequency divider 16 together with the clock input time ra 13 connected to the output of the clock generator 17. The magnetoelectric transducer 18 is connected through a preamplifier 19 with an input differentsiaoe installed in the bottom part of the container being tested b

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torus BUT. The first 1 and second 22 regenerative comparators are connected to the output of the differentiator. To the pyhod of the first regenerative comparator 21 is connected by the first input a static trigger 14 directly, and to the pyhode of the second regenerative comparator 22 by the second input to the skull 23 impulse delay unit. To the information outputs of the random access memory 11 via the reprogrammed 1mixable memory (P1PU). connected block. 5 digital display.

The gauge works as follows.

From the output of the clock generator 17, divide 16 frequencies and an element; UTH 15 pulses arrive at the counting input of the binary counter 12, which implements the counting of pulses on a cumulative basis.

At the same time, at the output of the digital-to-analog converter 10, a potential is formed at a given speed, and by increasing it, the current at the output of the DC amplifier 9 proportionally increases, thereby increasing the intensity of the magnetic field of the electromagnet 8.

| After the buoyancy force of the fluid and the force of the interaction of the magnetic field of the electromagnet 8 with the core 3 total exceeds the force of gravity of the cylindrical float 1, the latter will emerge. At the same time, at the output of the magnetoelectric converter 18, the potential decreases due to a change in the magnetic induction due to an increase in the distance between the magnetoelectric converter 18 L of the permanent magnet L.

Amplified by iredamplifier 19 and differentiated by differentiator A) a negative polarity pulse is fed to the inputs of the comparators 21 and 22.

Only the first one will work.

regenerative comparator 2, the logical unit from the output of which goes to the first input of the static trigger 14, the output of which also forms the level of the logical unit. At the same time, the MIDI element 15 will cease to pass the audio from the output of the divider 16 to the counting pass of the binary counter 1 -, the information on the output of which will cease to be measured.

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At the same time, using the level of the logical unit formed at the output of the trigger 14, the timer 13 is started, on the second and first outputs of which two pulses are sequentially generated.

(; using a pulse arriving from the second output of timer 13, the information from the output of binary counter 12 will be overwritten into random access memory 11 and after being converted by LIZU, 14 is displayed on digital display unit 25.

Thus, in an electromagnetic flow meter, information is recorded when the inequality

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where t is the power of tin of the cylindrical float; Р „- ejector force control1

ruemon fluid;

K is the interaction force between the magnetic field of the electromagnet 8 and the core of magnetic material.

From the p level of the monitored fluid, the ejection of the Fft ejector will increase, and therefore the force F will decrease accordingly, at which the cylindrical float 1 will float. Moreover, the force F is a function of the code at the information output of the binary counter 12.

With the arrival of the logical unit level from the first timer 13 output to the binary zero setting input (quarter 12), the latter is zeroed.

In this case, the potential at the output of the digital-analog converter 10 and the current at the output of the amplifier 9 of the direct current will be equal to zero.

In the absence of the magnetic field of the electromagnet I, the cylindrical float 1 is lowered again, and its position in the controlled volume 6 will be fixed with the help of the threads 4 and 5.

When a cylindrical pick 1 is immersed, the permanent magnet 2 moves closer to the magnetoelectric transducer 18, the output signal of which increases in this case.

 - A preamplifier 19i and a signal differentiated by a 2h differentiator in the form of a short pulse is fed to the inputs of regenerative comparators.

At -JTOM, the second comparator is triggered,., The output of which is formed516

the pulse, which, after the delay by the block .3, for the time necessary for calming the cylindrical float 1, arrives at the second input of the static trigger, at the output of which the logical zero level is forced.

In this case, the OR 15 element opens again and starts to transmit pulses g of the output of divider 1 of frequency i to the counting input of counter 1.1.

Since the output of the installation of zero of binary counter 12 will be at the level of logical zero, it will again begin counting pulses with a napier total.

Formula of invention

The ZLS-kromatirovni level gauge, containing a cylindrical float of negative buoyancy with a core made of magnetic material installed in its upper part, is so that, in order to improve the measurement accuracy, a constant a magnet mounted at the bottom of a cylindrical float, an electromagnet, a series-connected clock generator, a frequency divider, an And element, a binary

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a counter, a digital-analog converter and a DC amplifier, a digital diode connected to an electro-electromagnetic converter mounted at the bottom of a monitored capacitor, a preamplifier, a differentiator, a first regenerative

comparator, trigger and timer, sequentially connected random access memory, inputs connected to the outputs of a binary counter, reprogrammable memory

a device and a display unit, sequentially connected to a second regenerative comparator connected to the output of the differentiator, and a pulse delay unit connected to the output to the second input of the trigger, with the output of the clock generator connected to the clock input of the timer; the first and second outputs of which are connected respectively to the input of the installation of the counter and the recording entry of the random access memory, the output of the trigger is connected to the second input of the element I, the internal float is suspended on two threads to the flange,

which is installed electromagnet.

Claims (1)

SUMMARY OF THE INVENTION An electromagnetic level gauge containing a cylindrical negative buoyancy float with a core made of magnetic material mounted on its upper part is noteworthy in that, in order to increase the measurement accuracy, . we are a permanent magnet installed in the bottom of a cylindrical float, an electromagnet, a series-connected clock generator, a frequency divider, an AND element, a binary counter, a digital-to-analog converter and a DC amplifier, a digital output connected to an electro5 magnet, a series-connected magnetoelectric converter installed in the bottom of the monitored capacitance, preamplifier, differentiator, first regenerative 10 comparator, trigger and timer, connected in series an external memory device connected to the outputs of the binary counter, a reprogrammable memory device 15 and an indication unit connected in series to a second regenerative comparator connected to the output of the differentiator and a pulse delay unit connected to the output of the trigger to the second trigger input, the output of the clock generator being connected to timer clock input; the first and second outputs of which are connected respectively to the input of the counter installation 25 and the recording input of the random access memory, the trigger output is connected to the second input of the And element, the cylindrical float is suspended on two threads to a flange, on which 30 an electromagnet is mounted.