RU8468U1 - DEVICE FOR MEASURING FLOWS OF LIQUID AND GAS MEDIA - Google Patents

Abstract

1. A device for measuring the flow rate of liquid and gaseous media, containing a measuring section of the pipeline, at the input of which a label former is installed, and at the output there is a registration sensor, the output of which is connected to the first input of the comparator, the second input connected to the output of the reference sensor, and the output to the input of the label former and to the input of the measuring circuit, including a frequency counter, characterized in that a second measuring section of the piping, which is equivalent to the first and is installed next to it in the general medium flow, is introduced into it water, at the input of which a second label former is installed, and a reference sensor is installed at the output, while the input of the second label former is connected to the inverse output, and the input of the first former is connected to the direct output of the comparator, the first of which is inverted, and the second is direct, the output counter connected to the indicator input. 2. The device according to claim 1, characterized in that the sensors are introduced into the comparator, forming together with it an oscillator. The device according to claim 1, characterized in that the formers of the labels are thermocouples, and the sensors are thermally sensitive. The device according to claim 1, characterized in that the number of measuring sections of the pipeline is more than two.

Description

Device for measuring the flow rate of liquid and gaseous media

The utility model relates to means for measuring the flow of liquids and gases using labels inside the fluid and can be used in utilities, automobiles, the chemical industry, etc.

A device for measuring the flow rate of liquid and gaseous Fed, described in paragraph France No. 2623617 class. GO IF 1/68, c. 11/18/87, op. 05/26/89 A device for measuring the flow of liquid or gas in a pipeline.

The known device comprises a measuring pipe, a tag former mounted on it in the form of a heated element connected to a heater for receiving a tag, several temperature sensors arranged in series along the pipeline and connected to the measurement circuit.

A disadvantage of the known device is. that its accuracy is low, because the mark cools as it moves along the Tp j npole from one sensor to another, and to ensure the necessary accuracy, the signal must be linked to a certain level, which changes in this technical solution.

MKI-6: 1/00, 1/704

A device for measuring the flow rate of liquid media, described in 3. France, No. 2611269 class. GO IF 7/00, 1/00 Combined water meter, c. 08/29/87 (West Germany No. 3705218), Op. 26.08.88.

The known device comprises two main measuring pipelines for high flow rates with a primary meter installed in it and an additional one with an additional low flow meter installed in it, a switching valve with a shut-off element installed in the main channel behind the main meter in the tubular tip of the measuring device of the main meter; while the locking element is equipped with a spring and has the ability to move along the axis to open or close the passage through the main pipeline when the specified pressure drop is reached.

A disadvantage of the known device is its complexity - the presence of two counters - the main and additional in the channels for high and low flow rates - due to the fact that otherwise the design does not provide measurements of a sufficiently large flow range.

The closest in technical essence to the claimed is a device for measuring the flow of liquid and gaseous media, described in application No. 94038133/28/038054 A method of measuring the flow of liquid and gaseous media and a device for its implementation according to cl. GO IF 1/00, 1/704, according to which a decision was made to extend the patent from

01/23/96, the corresponding fees were paid, and selected as a prototype.

The known device contains a measuring section of the pipeline, at the input of which there is a label former in the form of a heater, and in front of it is a reference sensor, the output of which is connected to one input of the comparator, to the second input of which is connected the output of the registration sensor installed at the output of the measuring section of the pipeline, the output of the comparator connected to the input of the label former and to the input of the flow measurement circuit, consisting of a frequency divider and a pulse counter connected in series.

A disadvantage of the known device is its unsatisfactory accuracy and sensitivity, due to the presence of one measuring pipeline and the installation of a reference sensor at the input and a registration sensor at the output, due to which the comparator fails once on the front label signal frack, and a second time on it trailing edge - decline; moreover, if the leading edge can be set by a powerful heater and be steep enough, then the decline is not adjustable (it depends on the cooling speed of the mark). This difference in the level of the compared signals results in a significant measurement error. The difference between the sensor signals is also small, so the sensitivity of the device is insufficient.

The purpose of the claimed utility model is to increase the accuracy of measurements and the sensitivity of the device.

This goal is achieved by the fact that in the device for measuring the flow rate of liquid and gaseous media containing a measuring section of the pipeline, at the input of which a label former is installed, and at the output there is a registration sensor, the output of which is connected to the first input of the comparator, the second input connected to the output of the reference sensor and the output - to the input of the mettsi shaper and to the input of the measurement circuit that includes the counter, according to the utility model, a second one is entered, equivalent to the first and installed next to it in the general medium flow from a measuring pipe, at the input of which a second label former is installed, and a reference sensor is installed at the output, while the input of the first label former is connected to the direct output of the comparator, and the input of the second former is connected to the inverted output of the comparator, the first input of the comparator is inverse, and the second input is direct, the counter output is connected to the indicator input.

In this case, the sensors are introduced into the comparator, forming together with it an oscillator.

In this case, the shapers of the tags are thermocouples, and the sensors are made thermosensitive.

in addition, the number of measuring sections of the pipeline may be more than two.

Introduction to the measuring device of a second pipeline equivalent to the first measuring section with the second label former and the reference sensor installed in it, in conjunction with the connection of the first former and the direct, and the second with the inverted outputs of the comparator and the outputs of the registration sensor and the reference sensor, respectively, with inverse and direct the comparator inputs allows you to compare sensor signals on steep leading edges and significantly reduces the measurement error; the range of the signal difference between the sensors, provided by the connection scheme of the sensors with the comparator, increases by about a factor of two, this increases the sensitivity of the device.

The introduction of sensors in the comparator circuits} for the formation of a self-oscillator together with it makes it possible to ensure high sensitivity of the sensor to the marks and to connect the autogenerator directly to digital indication circuits.

The use of thermocouples as shapers and the implementation of thermally sensitive sensors simplifies the implementation of the device.

The number of measuring sections more than two gives a multiphase system, where the spread of the parameters and technological tolerances of the measurement is removed, which increases accuracy.

The inventive device has a novelty in comparison with the prototype, differing from it by the presence of a second measuring section of the pipeline with a second tag former and a reference sensor installed in it, as well as the connections of the tag formers and sensors with the comparator.

In addition, the inclusion of sensors in the comparator circuit for the formation of a self-oscillator and the use of the number of measuring sections of more than two may be new.

The inventive device can be widely used in utilities, in the operation of automobiles, in the chemical industry, etc. , and therefore meets the criterion of industrial applicability. The utility model is illustrated by drawings, which are presented on;

-Fig. 1 is a diagram of a flow measuring device;

-Fig. 2 are diagrams illustrating the operation of the device.

A device for measuring the flow rate of liquid and gaseous media contains two equivalent measuring sections 1, 2 of the pipeline, installed side by side in the general stream of the fed, at the inlet of each of which there is a shaper 3, 4 tags. At the exit of the first

of section 1, a recording sensor 5 is installed, and at the output of the second section 2, a reference sensor 6, while the output of the sensor 5 is connected to the inverse input of the comparator 7, and the output of the reference sensor 6 is connected to the direct input of the comparator 7. The inverse output of the comparator 7 is connected to the input of the second the shaper 4 labels, and its direct output is connected to the input of the shaper 3 labels and to the input of the measurement circuit 8, consisting of series-connected counter 9 and indicator 10.

The purpose and implementation of the nodes and elements of the device is as follows. Measuring port I and 2 pipelines are used for measurements.

Shapers 3, 4 labels are designed to create at the input of the measuring sections 1, 2 labels in the form of an abnormal, for example, thermal region and are made, in particular, in the form of nichrome spirals.

The registration sensor 5 and the reference sensor 6 are used to measure the fedora’s temperature, they are heat-sensitive and each is made on a KT625 microtransistor. (see. Handbook Transistors of medium and high power. Edited by A.V. Golomedov, ed. 2nd Radio and Communications, M. 1994. p. 271).

Comparator 7 is designed to provide a signal at the output when it receives a signal that a tag has arrived at sensor 5 or 6. It is made on a 544CAZ chip with two emitter repeaters and

yjgajux yy jt vu {shdral & disch, 2a-b5us e,

one inverter on the transistor KT817 (see the above manual).

The measurement circuit 8 serves to provide a measurement result and consists of a counter 9 and an indicator 10.

The pulse frequency counter 9 counts the number of pulses from the output of the comparator 7 and is executed on a PIC16F84 type P1C controller (see MICROCHIP catalog).

The indicator 10 is designed to display the flow rate in units of volume, for example, in liters and graduated by the formula:

 I VHSM Vpacx / ceK

where f is the label repetition rate, V is the volume.

The indicator is made on LCD crystals.

The device operates as follows. (See FIGS. 1 and 2).

The medium, the flow rate of which is measured, is supplied by the operator to the input of the measuring sections 1, 2 TRZ of the line. At the first time, the signals at the outputs of the registration sensor 5 and the reference sensor 6 are approximately the same and equal to zero. However, the signals at the outputs of the comparator 7 due to the natural imbalance are different, for example, zero (logical O) on the direct and single (logical 1) on the inverse output; the latter enters the second shaper 4 tags and turns it on. A thermal mark is formed (see FIG. 2-a), which begins to move along the second measuring section 2; when

it reaches the reference sensor 6, the signal at its output changes to a single one, and arriving at comparator 7, changes the signals at its outputs - a single signal appears at the direct output, and zero at the inverse. Now a single signal is fed to the input of the shaper 3 labels and turns it on. the heat label begins to move along the measuring section 1 of the pipeline and reaches the sensor 5 registration. A single signal comes from the output of the sensor 5 to the input of the comparator 7 and along its rising edge at the output of the comparator 7, the signals are again reversed: the label former 4 is turned on again and the process is repeated. The voltage drops at the output of the comparator 7 in the form of pulses with a duty cycle of approximately 2 are calculated by the frequency counter 9 of the measurement circuit 8 and the frequency of their repetition, indicated on the indicator 10, is directly proportional to the flow rate.

In comparison with the prototype of the inventive device for measuring flow is more accurate and sensitive.

The author is Mr. Nagovitsyn AL.

Claims (4)

1. A device for measuring the flow rate of liquid and gaseous media, containing a measuring section of the pipeline, at the input of which a label former is installed, and at the output there is a registration sensor, the output of which is connected to the first input of the comparator, the second input connected to the output of the reference sensor, and the output to the input of the label former and to the input of the measuring circuit, including a frequency counter, characterized in that a second measuring section of the piping, which is equivalent to the first and is installed next to it in the general medium flow, is introduced into it water, at the input of which a second label former is installed, and a reference sensor is installed at the output, while the input of the second label former is connected to the inverse output, and the input of the first former is connected to the direct output of the comparator, the first of which is inverted, and the second is direct, the output counter connected to the input of the indicator.  2. The device according to claim 1, characterized in that the sensors are introduced into the comparator, forming together with it an oscillator.  3. The device according to claim 1, characterized in that the formers of the labels are thermocouples, and the sensors are thermally sensitive.  4. The device according to claim 1, characterized in that the number of measuring sections of the pipeline is more than two.