SU1675682A1 - Float-type level indicator - Google Patents

Abstract

The invention relates to instrumentation engineering and makes it possible to increase the accuracy of measuring the level of aggressive and explosive liquids. When a control signal appears, a current flows through the coil of the solenoid 6, as a result of which a core 3 of magnetic material is drawn into the solenoid 6 together with a cylindrical float 1. When the extreme upper position is reached, the measuring circuit is started and the current through the solenoid 6 is turned off. float 1 begins to sink. The immersion speed and the time the float reaches the lowest lower value are determined by the level of the liquid in the monitored tank 4. When the float reaches the extreme position, the measurement circuit is turned off, consisting of a clock generator 19, a counter 20. timer 18, a random access memory 21 and a persistent memory 22. The measurement result is displayed on the display unit 23. 1 il. W o o VI ate Os 00 hO

Description

The invention relates to instrument engineering and is intended to control the level of aggressive and explosive liquids.

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

The drawing shows a block diagram of a float gauge.

The level gauge contains a cylindrical float 1, at the bottom of which there is a permanent magnet 2, and in the upper part there is a core 3 made of magnetic material, placed in a non-magnetic material fixed to a monitored capacitance A, 5, on which a solenoid 6 and a Wigand 7 sensor are mounted. . A comparator 8 is connected to the output of Wigand's sensor 7 and connected via its output via a delay unit 9 to the first input of the trigger 10 connected to the second input through a series-connected regenerative comparator 11, differentiator 12 and preamplifier 13 to the output of the magnetoelectric converter 14 mounted on the bottom controlled capacitance 4. To the output of trigger 10, connected in series are amplifier 15, amplifier 16, direct current and solenoid 6, OR circuit 17, and timer start input 18. Clock input the timer is connected to the second input of the OR circuit 17 and to the output of the clock generator 19, while the first and second outputs of the timer 18 are connected respectively to the zero input input of counter 20 and the random access memory recording input 21, through which constant information is connected to the information outputs of the counter 20 memory 22 and display unit 23.

The gauge works as follows.

Let the output of the trigger 10 there is a level log. 1. In this case, a high level potential is formed at the output of the amplifier 15 and a current flows through the solenoid 6 connected to the output of the amplifier 16, causing a magnetic field to appear, by means of which the core 3 is drawn into the inside of the solenoid 6.

When the core 3 reaches an extremely high position due to an increase in magnetic induction, the Wigand sensor 7 is triggered and a short pulse is generated at its output, which arrives at the input of the comparator 8, from which the pulse of a given polarity is formed after a delay of the time required for the end of transients and rewriting information from the output of the delay unit is fed to the first input of the static trigger 10, on

the output of which at the same time forms the log level. A. At the same time, at the outputs of amplifiers 15 and 16, respectively, the voltage and current are zero, and consequently, the magnetic field of solenoid 6 is zero.

With the disappearance of the magnetic field of the solenoid 6, the cylindrical float 1 begins to sink. Moreover, the rate of its immersion decreases with an increase in the level of liquid in the controlled container 4 due to an increase in the Archimedean force.

The immersion time of the cylindrical float from the extreme upper position and the extreme lower position is determined by the counter 20 connected by a counting input through the OR circuit 17 to the output of the clock generator 18. When the cylindrical float 1 reaches the lowest lower position, the output potential increases as the permanent magnet 2 approaches. magnetoelectric converter 14.

The signal amplified by the preamplifier 13 and differentiated by the differentiator 12 in the form of a short pulse arrives at the input of the regenerative comparator 11, at the output of which a log level is formed. 1 with the arrival of which to the second input of the trigger 10, a log level is formed at its output. G.

When level 1 arrives at the first input of the OR circuit 17, the latter ceases to transmit pulses from the output of the reference generator to the counting input of counter 20, after which the information at its output ceases to change.

With the entry level log. 1, from the output of trigger 10 to the start input of timer 18, at its second and first outputs, a sequence of two pulses is formed, with which the information from the output of counter 20 is copied to the random access memory 21, and then the counter 20 is zeroed.

With the advent of level log. 1, at the output of trigger 10, a magnetic field is again formed in the solenoid and the entire measurement cycle is repeated.

Claims (1)

Invention Formula A float gauge containing a solenoid mounted on the nozzle, connected to the output of a DC amplifier, a core of magnetic material installed inside the nozzle, connected to a cylindrical float, characterized in that, in order to improve the measurement accuracy, a permanent magnet is inserted into it the bottom of a cylindrical float, a magnetoelectric converter, A preamplifier connected to the output of a magneto-electric converter, a differentiator, a regenerative comparator, a trigger and an amplifier connected to the input of a DC amplifier, series-connected clock generator, OR circuit, counter, connected to the outside of the controlled capacitance coaxially with a cylindrical float. random-access memory device and display unit connected in series Wigand sensor mounted on the nozzle coaxially with the solenoid, a comparator and a delay unit connected to the second trigger input, timer, start input connected to the trigger output and the second input of the OR circuit, first and second outputs to the input zeroing the counter and to the recording entry of the random access memory, respectively, and the clock input to the output of the clock generator.