KR102025985B1 - Mass flow control apparatus using capacitance measuring and mass flow control method using the same - Google Patents

Abstract

Mass flow rate control apparatus using the capacitance measurement according to an embodiment of the present invention comprises a first capacitor located on the movement path of the fluid; A second capacitor spaced apart from the first capacitor and positioned on the movement path of the fluid; A measuring circuit connected to the first and second capacitors and measuring first and second capacitances of the fluid through the first and second capacitors; And a controller configured to measure and control the flow rate of the fluid moving on the movement path of the fluid based on the capacitance value measured from the measurement circuit.

Description

Mass flow control device using capacitance measurement and mass flow control method using same {MASS FLOW CONTROL APPARATUS USING CAPACITANCE MEASURING AND MASS FLOW CONTROL METHOD USING THE SAME}

The present invention relates to a mass flow control device using capacitance measurement and a mass flow control method using the same.

Gas or gas measurement by mass flow rate has been efficiently applied in various industrial fields. Typical flowmeters for measuring gases or gases include orifices, differential pressure flowmeters, vortex flowmeters, turbine flowmeters, ultrasonic flowmeters, area flowmeters, and thermal mass flowmeters.

Among these flowmeters, except for the thermal mass flow meter, only the volume of the fluid is measured. The temperature or pressure of the process requiring the fluid measurement can not be properly compensated when it differs from the design. It is a flow meter which measures only quantity.

A thermal mass flow meter is also known as a classification tubular flow meter. In the thermal mass flow meter, when a heated object is placed in a flowing fluid, the heated object is cooled as heat exchange occurs between the fluid and the heated object. Since this cooling rate is a function of the flow rate, the flow rate can be obtained by measuring the temperature of the heated object. In addition, since the energy required to heat the fluid to a constant temperature is a function of the flow rate, the flow rate can be obtained by measuring the energy required to raise the flowing fluid to a certain temperature.

1 is a view showing the principle of measuring the flow rate.

Referring to FIG. 1, a measuring tube 120, which is a long U-shaped capillary tube (also referred to as bypass), is formed in a main pipe 110 that is a pipe through which a fluid passes. The measuring tube 120 is provided with first and second resistance heating elements 122 and 124 at predetermined intervals. In the case where the fluid does not flow, the first and second resistance heating elements 122 and 124 of the measurement tube 120 are thermally balanced to have the same temperature. However, when the fluid flows, heat is moved by the flow of the fluid. Therefore, the thermal equilibrium is broken and a temperature difference occurs between the first and second resistance heating elements 122 and 124. The generated temperature difference is detected through the measuring circuit 126 and the controller 130. Based on the temperature difference in the measuring tube 120 can be measured by inferring the flow rate of the fluid flowing in the main pipe (110).

However, since the flow rate is measured using the temperature difference, it may be affected by the external environment (for example, the temperature of the place where the main pipe is installed). In addition, the value measured by the measuring circuit 126 is corrected using an algorithm and then transferred to the controller 130, and the controller 130 measures the flow rate of the fluid based thereon. The controller 130 controls the flow rate of the fluid passing through the main pipe 110 by driving the motor 162 connected to the valve 164 based on the measured flow rate. If the correction value accumulates in the repeated flow measurement process, a deviation between the actual flow rate and the corrected value occurs. These deviations can cause difficulties in measuring the correct flow rate of the fluid. In addition, accurate flow control requires accurate flow measurement.

Modern industries have been increasingly sophisticated and diversified, and high precision fluid measurement is required in a wide variety of processes for measuring the flow of fluids, especially gases. Expensive flow rate measuring device is required for high accuracy measurement.

An object of the present invention is to measure the capacitance value of a fluid using a capacitor and then to measure the flow rate of the fluid using the same, the mass flow rate control device using the capacitance measurement capable of controlling the flow rate and the mass flow rate control method using the same To provide.

In order to solve the above technical problem, the mass flow control device using the capacitance measurement according to an embodiment of the present invention is spaced apart from the first capacitor, the first capacitor located on the fluid path of the fluid A second capacitor located on a movement path, a measurement circuit connected to the first and second capacitors and measuring first and second capacitances of the fluid through the first and second capacitors, and from the measurement circuits It may include a control unit for measuring and controlling the flow rate of the fluid moving on the movement path of the fluid based on the measured capacitance value.

In some embodiments, each of the first capacitor and the second capacitor may include a pair of first and second plates and a pair of third and fourth plates provided to face each other.

In an embodiment, at least one or more of the first capacitor and the second capacitor may be located inside a fluid movement tube including a movement path of the fluid.

In some embodiments, at least one of the pair of first and second plates and the pair of third and fourth plates may be positioned in the same direction as the fluid moves, or the fluid may move. It may be located in a direction different from the direction to.

In some embodiments, the first and second plate pairs and the third and fourth plate pairs may be provided in at least one pair of at least one pair, and the intervals between the plates may be spaced at regular intervals or at non-uniform intervals. Can be spaced apart.

In example embodiments, the measurement circuit may include a bridge circuit.

In an embodiment, the apparatus may further include a flow rate distributor configured to at least one or more of the first and second plates and the third and fourth plates to distribute the flow of the fluid.

In an embodiment, the flow rate distribution part may include a distillation element.

In an embodiment, the controller may further include a control valve configured to control the flow rate of the fluid moving on the fluid movement path by controlling the opening and closing.

According to an embodiment of the present invention, a flow rate control method using a mass flow rate control apparatus using capacitance measurement includes a step of moving a fluid into a fluid moving tube, wherein the mass flow rate control apparatus according to any one of claims 1 to 9 is used. Measuring a first capacitance value of the fluid by using a first capacitor; a second capacitance of the fluid by using a second capacitor of the mass flow controller according to any one of claims 1 to 9 Measuring a value, transferring the first and second capacitance values measured by the first and second capacitors to a controller, based on the measured first and second capacitance values, by the controller Measuring the flow rate of the fluid, and controlling the flow rate of the fluid in the control unit.

The control unit may measure the first and second capacitance values sequentially using the first and second capacitors, or simultaneously use the first and second capacitors to simultaneously measure the first and second capacitors. 2 Capacitance value can be measured.

Referring to the effect of the mass flow control device using the capacitance measurement according to the present invention and the mass flow control method using the same as follows.

According to at least one of the embodiments of the present invention, it is possible to accurately measure the flow rate of the fluid flowing using the capacitor. Based on this, accurate flow control is possible.

In addition, according to at least one of the embodiments of the present invention, the capacitor can be installed in the tube through which the fluid flow, it is not necessary to provide a separate measuring tube for the flow rate measurement.

1 is a view showing the principle of measuring the flow rate.
2 is a view showing the concept of a mass flow controller according to a preferred embodiment of the present invention.
3 is a view showing a mass flow controller according to a preferred embodiment of the present invention.
4 is a view showing the first and second capacitors of the mass flow controller according to an embodiment of the present invention.
5 is a view showing a measuring circuit of the mass flow controller according to a preferred embodiment of the present invention.
6 is a view showing a mass flow control device according to another embodiment of the present invention.
7 is a view showing a mass flow control device according to another preferred embodiment of the present invention.
8 is a view showing a mass flow control device according to another preferred embodiment of the present invention.
FIG. 9 is a view showing a cross section of the mass flow controller of FIG. 8. FIG.
10 is a flowchart illustrating a method of controlling a flow rate of a fluid using a mass flow controller according to a preferred embodiment of the present invention.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings, and the same or similar components are denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used in consideration of ease of specification, and do not have distinct meanings or roles from each other. In addition, in describing the embodiments disclosed herein, when it is determined that the detailed description of the related known technology may obscure the gist of the embodiments disclosed herein, the detailed description thereof will be omitted. In addition, the accompanying drawings are intended to facilitate understanding of the embodiments disclosed herein, but are not limited to the technical spirit disclosed herein by the accompanying drawings, all changes included in the spirit and scope of the present invention. It should be understood to include equivalents and substitutes.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, the terms "comprises" or "having" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It is apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential features of the present invention.

2 is a view showing the concept of a mass flow controller according to a preferred embodiment of the present invention.

Referring to FIG. 2, the mass flow controller 200 of the present invention may include a first capacitor 220, a second capacitor 230, a measurement circuit 250, and a controller 260. The first and second capacitors 220 and 230 may be located on a movement path through which the fluid moves. In the exemplary embodiment of the present invention, the first and second capacitors 220 and 230 may be provided inside the fluid movement pipe 210. The fluid movement tube 210 may be provided with a hollow space in which the fluid moves inside the tubular shape. The fluid may move while flowing into the inner space of the fluid movement pipe 210. The fluid movement pipe 210 may be a separate pipe having the first and second capacitors 220 and 230 provided therein. In this case, the fluid movement pipe 210 may be inserted in the middle of a general conduit (main pipe) through which the fluid is moved. Alternatively, the first and second capacitors 220 and 230 may be inserted into a general conduit (main pipe) through which the fluid moves. The fluid moving tube 210 may be, for example, a quartz tube.

In the present invention, a case where the first and second capacitors 220 and 230 are provided inside the fluid movement pipe 210 which is a general conduit will be described. The fluid moving along the fluid movement pipe 210 may be moved while sequentially passing through the first capacitor 220 and the second capacitor 230. The first and second capacitors 220 and 230 are configured to measure capacitance values of the fluid.

In the present invention, a case in which two capacitors 220 and 230 are used is illustrated and described based on this. However, the number of capacitors is not limited, and three or more capacitors may be used.

The measurement circuit 250 may be electrically connected to the first and second capacitors 220 and 230, and measure capacitance values of the fluid passing through the first and second capacitors 220 and 230. The measured capacitance value of the fluid correlates with the permittivity of the fluid passing through the fluid motion tube 210, the speed of fluid movement, the cross-sectional area of the fluid motion tube 210 and the density of the fluid (hereinafter referred to as parameters for flow measurement). Has Therefore, the flow rate of the moving fluid can be measured using the capacitance value of the fluid.

The first and second capacitors 220 and 230 may be sequentially driven to measure capacitance values of the fluid. In another embodiment, the first and second capacitors 220 and 230 may be driven simultaneously to measure capacitance values of the fluid.

The controller 260 may receive the capacitance values measured by the first and second capacitors 220 and 230 from the measurement circuit 250 and perform an algorithm for measuring the flow rate of the fluid based on the capacitance values. The controller 260 may include a flow rate measuring unit 262 and a control signal generator 264. The flow rate measuring unit 262 may measure the flow rate of the fluid using the capacitance values measured by the first and second capacitors 220 and 230 through the measuring circuit 250. The flow rate measuring unit 260 may store data on the flow rate of the fluid according to the capacitance value by an algorithm. The flow rate measuring unit 262 may be connected to the control signal generator 264. The control signal generator 264 may generate a control signal and control the opening and closing of the control valve 274 provided in the fluid movement pipe 210 by controlling the motor 272 using the control signal. It is determined whether the control of the control valve 274 is necessary according to the flow rate of the fluid measured by the flow rate measuring unit 262, and if it is determined that the control of the control valve is necessary, the control signal through the control signal generator 264 By controlling the flow rate of the fluid can be controlled by adjusting the opening and closing degree of the control valve 274.

The mass flow control apparatus 200 may further include a display unit (not shown). The display unit may display the capacitance of the fluid measured by the first and second capacitors 220 and 230 and the flow rate of the fluid measured by the controller 260 using the measurement circuit 250. The display unit may be located outside the fluid movement tube 210, and the user may check the flow rate of the fluid moving inside the fluid movement tube 210.

3 is a view showing a mass flow controller according to a preferred embodiment of the present invention.

Referring to FIG. 3, the first capacitor 320 may be configured as a pair of first and second plates 322 and 324. The first and second plates 322 and 324 may be manufactured as a conductor in a plate shape. The first and second plates 322 and 324 may be spaced apart to face each other at regular intervals, and in particular, may be provided inside the fluid movement tube 310. Fluid may pass through the spaces between the first and second plates 322 and 324 facing each other, such that the first and second plates 322 and 324 may function as the first capacitor 320. Although the first and second plates 322 and 324 are illustrated in a rectangular plate shape, the first and second plates 322 and 324 may be modified in various shapes to measure the capacitance of the fluid.

A portion of the fluid passing through the fluid moving tube 310 may move through the space between the first and second plates 322 and 324. When the fluid is moved, the measurement circuit 250 may be used to measure the capacitance value of the fluid passing through the first and second plates 322 and 324.

For example, the first and second plates 322 and 324 may be provided to face in the same direction as the moving direction of the fluid. The fluid movement tube 310 may be positioned at an upper portion in the internal space, and the second plate 324 may be positioned at a lower portion in the fluid movement tube 310 in the inner space so as to face the first plate 322. The first and second plates 322 and 324 may be connected to the measurement circuit 250.

The second capacitor 330 may be configured of the third and fourth plates 332 and 334 in the same manner as the first capacitor 320. The third and fourth plates 332 and 334 may be manufactured as conductors in a plate shape. The third and fourth plates 332 and 334 may be spaced apart to face each other to have a predetermined interval, and in particular, may be provided inside the fluid movement tube 310. Fluid may pass through the spaces between the third and fourth plates 332 and 334 facing each other, such that the third and fourth plates 332 and 334 may function as the second capacitor 330. Although the third and fourth plates 332 and 334 are illustrated in a rectangular plate shape, the third and fourth plates 332 and 334 may be modified in various shapes capable of measuring the capacitance of the fluid.

A portion of the fluid passing through the fluid moving tube 310 may move through the space between the third and fourth plates 332 and 334. When the fluid is moved, the capacitance of the fluid passing through the third and fourth plates 332 and 334 may be measured using the measuring circuit 250.

For example, the third and fourth plates 332 and 334 may be provided to face each other in a direction different from the moving direction of the fluid (eg, perpendicular to the moving direction of the fluid). The third plate 332 may be located forward in the fluid movement tube 310 internal space, and the fourth plate 334 may be located rearward in the fluid movement tube internal space to face the third plate 332. The third and fourth plates 332 and 334 may be connected to the measuring circuit 250.

Fluid moving inside the fluid movement tube 310 may move while passing through the first capacitor 320 and the second capacitor 330. In this case, the first and second capacitance values of the fluid passing through the first and second capacitors 320 and 330 may be measured using the measuring circuit 250. Here, since the fluid moves through the first and second capacitors 320 and 330, the first and second capacitance values measured by the first and second capacitors 320 and 330 continue to change. Therefore, the flow rate measuring unit 260 may measure the flow rate using the measured change rate of the capacitance value as a parameter for measuring the flow rate.

A flow distribution part 340 may be further provided between the first capacitor 320 and the second capacitor 330 so that the fluid is evenly distributed and flows in the fluid movement tube 310. The flow rate distributor 340 may perform a function of uniformly distributing the fluid in order to prevent the fluid from concentrating and passing through a portion of the fluid movement pipe 310. The flow rate distributor 340 may include, for example, a distillation element.

4 is a view showing the first and second capacitors of the mass flow controller according to an embodiment of the present invention.

Referring to FIG. 4, the first and second plates 422 and 424 and the third and fourth plates 432 and 434 may be positioned at predetermined intervals d1 and d2. The first to fourth plates 422, 424, 432, and 434 have a plate shape, and the facing areas thereof vary according to the widths w1 and w2.

The first and second capacitance values measured through the first and second capacitors 420 and 430 pass between the first and second plates 422 and 424 and the third and fourth plates 432 and 434. It is closely related to the permittivity, density, and velocity of the fluid. Therefore, the capacitance of the fluid may be measured using the first and second capacitors 420 and 430, and the flow rate of the fluid may be measured using the same.

The first and second plates 422 and 424 and the third and fourth plates 432 and 434 may adjust the area facing each other. Alternatively, the distance between the first and second plates 422 and 424 and the third and fourth plates 722 and 724 may be adjusted.

The first to fourth plates 422, 424, 432, and 434 may be formed in the same area, and may be formed in different areas, respectively. Alternatively, the areas of the facing plates may be the same or different from each other. In addition, the first and second plates 422 and 424 may be spaced at regular intervals or spaced at irregular intervals. Alternatively, the third and fourth plates 432 and 434 may be spaced at regular intervals or spaced at irregular intervals.

5 is a view showing a measuring circuit of the mass flow controller according to a preferred embodiment of the present invention.

Referring to FIG. 5, the measurement circuit 550 in the present invention may include a bridge circuit. The bridge circuit includes two fixed resistors 540 and 545, first and second capacitors 520 and 530, and a power supply 510, and the capacitance through the first and second capacitors 520 and 530. The value can be measured. The measured capacitance value may be rectified and amplified through the amplifier 557 and transferred to the flow rate measuring unit 560.

In the flow rate measuring unit 560, an algorithm for measuring the flow rate using the capacitance value may be performed. The flow rate measuring unit 560 stores the capacitance value according to the flow rate of the fluid as data, so that the flow rate of the fluid can be measured by comparing the measured capacitance value with the stored data.

6 is a view showing a mass flow control device according to another embodiment of the present invention.

Referring to FIG. 6, the flow rate distributor 640 may be further included in the first and second capacitors 620 and 630. A flow rate distributor 640 may be provided between the first and second plates 622 and 624 and between the third and fourth plates 632 and 634. Fluid passing between the second plates 622 and 624 and the third and fourth plates 632 and 634 may be uniformly distributed and passed through.

Referring to FIG. 6A, the first and second plates 622 and 624 of the first capacitor 620 may face each other to be parallel to the direction in which the fluid moves. Here, the flow distribution unit 640 may be provided between the first and second plates 622 and 624. In addition, the third and fourth plates 632 and 634 of the second capacitor 630 may be provided to face each other to be perpendicular to the direction in which the fluid moves. A flow distribution unit 640 may be provided between the third and fourth plates 632 and 634.

Referring to FIG. 6B, the first and second capacitors 620 and 630 may be provided in the same manner as in FIG. 6A. Here, the flow distribution unit 640 may be provided between the first and second capacitors 620 and 630 as well as included in the first and second capacitors 620 and 630 as shown in FIG. . The fluid passing through the entire fluid movement pipe 610 may be uniformly distributed by the flow distribution unit 640.

The flow distribution unit 640 may be provided in at least one or more positions within the first and second capacitors 620 and 630 or between the first and second capacitors 620 and 630. The number of flow distribution units 640 is not limited to the number shown in the figure.

7 is a view showing a mass flow control device according to another preferred embodiment of the present invention.

Referring to FIG. 7, the first and second capacitors 720 and 730 may be variously located with respect to the moving direction of the fluid.

Referring to FIG. 7A, first and second plates 722 and 724 of the first capacitor 720 may face each other to be perpendicular to the direction in which the fluid moves. In addition, the first and second plates 732 and 734 of the second capacitor 730 may be provided to face each other in the same direction as the fluid moves. The first capacitor 720 and the second capacitor 730 may be provided in the same direction as the moving direction of the fluid or may be provided in different directions.

The flow distribution unit 740 may be provided in at least one of the first capacitor 720, the second capacitor 730, and the first and second capacitors 720 and 730.

Referring to FIG. 7B, the first and second plates 722 and 724 of the first capacitor 720 and the third and fourth plates 732 and 734 of the second capacitor 730 are fluids. It may be provided to face the same as the moving direction.

The flow distribution unit 740 may be included in at least one of the first capacitor 720, the second capacitor 730, and the first and second capacitors 720 and 730.

Referring to FIG. 7C, the first and second plates 722 and 724 of the first capacitor 720 and the third and fourth plates 732 and 734 of the second capacitor 730 are fluids. It may be provided to face perpendicular to the moving direction.

The flow distribution unit 740 may be included in at least one of the first capacitor 720, the second capacitor 730, and the first and second capacitors 720 and 730.

8 is a view showing a mass flow control device according to another preferred embodiment of the invention, Figure 9 is a view showing a cross section of the mass flow control device of FIG.

8 and 9, the first and second plates 822 and 824 of the first capacitor 820 may be provided in the fluid movement tube 810. In other words, the groove 812 may be formed to face each other in the fluid movement pipe 810, and the first and second plates 822 and 824 may be installed in the groove 812. Capacitive values of the fluid passing through the fluid moving tube 810 may be measured by the first and second plates 822 and 824.

In addition, third and fourth plates 832 and 834 functioning as the second capacitor 830 may be provided in the fluid movement tube 810. The third and fourth plates 832, 834 may be positioned to be perpendicular to the direction of movement of the fluid.

The installation directions of the first to fourth plates 822, 824, 832, and 834 may be applied to various modified embodiments described above, but are not limited to the drawings. In addition, although not shown in the drawings, a flow rate distribution unit may be provided as described above.

10 is a flowchart illustrating a method of controlling a flow rate of a fluid using a mass flow controller according to a preferred embodiment of the present invention.

Referring to FIG. 10, the fluid may be injected and moved into the fluid moving tube to allow the fluid to flow into the fluid moving tube (S110). The fluid moved in step S110 may pass through the first capacitor included in the fluid movement tube. The measurement circuit may measure a first capacitance value of the fluid flowing in the fluid movement tube through the first capacitor (S120). The fluid that has passed through the first capacitor may again pass through the second capacitor. The measurement circuit may measure a second capacitance value of the fluid flowing in the fluid movement tube through the second capacitor (S130). The flow rate measuring unit of the controller receives the first and second capacitance values measured from the measuring circuit (S140). The first and second capacitance values correlate with each other and also with the permittivity, density, and velocity of the fluid. Therefore, the flow rate of the fluid moving along the inside of the fluid movement tube can be measured using the capacitance value of the fluid (S150).

The controller determines whether to control the amount of fluid flowing into the fluid movement tube after measuring the flow rate of the fluid (S160). If it is determined that the flow rate of the fluid should be controlled, the control unit may control the opening and closing of the control valve. Opening and closing of the control valve is controlled to control the flow rate of the fluid (S170).

For example, if it is determined that the amount of fluid moving inside the fluid movement pipe is greater than the reference amount, the controller may control the motor to close the control valve. As the control valve is closed, the amount of fluid moved in the fluid movement tube can be reduced. Alternatively, when it is determined that the amount of fluid moving inside the fluid movement tube is less than the reference amount, the controller may control the motor to open the control valve. The controller may control the control valve to be completely opened or closed, or may control the opening / closing degree of the control valve. The opening and closing degree of the control valve may be determined according to the flow rate to be adjusted.

The first capacitor and the second capacitor may be simultaneously driven to measure the capacitance of the fluid, or the first capacitor and the second capacitor may be sequentially driven to measure the capacitance of the fluid.

The above detailed description should not be construed as limiting in all respects but should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

Claims (11)

A first capacitor located on the path of fluid movement;
A second capacitor spaced apart from the first capacitor and positioned on the movement path of the fluid;
A measuring circuit connected to the first and second capacitors and measuring first and second capacitances of the fluid through the first and second capacitors; And
A control unit for measuring and controlling the flow rate of the fluid moving on the movement path of the fluid based on the capacitance value measured from the measuring circuit,
Each of the first capacitor and the second capacitor,
A pair of first and second plates and a pair of third and fourth plates provided to be spaced apart and facing each other in the fluid moving tube through which the fluid is plate-shaped,
Mass flow control device using a capacitance measurement further comprises a flow rate distribution unit which is provided between at least one of the first and second plates and the third and fourth plates, and distributes the flow of the fluid.
delete delete The method of claim 1,
At least one pair of the first and second plate pair and the third and fourth plate pair,
Mass flow control device using a capacitance measurement is located in the same direction as the direction in which the fluid moves, or in a direction different from the direction in which the fluid moves.
The method of claim 1,
The interval between the plates provided in at least one pair of the first and second plate pair and the third and fourth plate pair,
Mass flow control with capacitive measurements spaced at regular intervals or spaced at irregular intervals.
The method of claim 1,
The measuring circuit,
Mass flow control device using capacitance measurement including a bridge circuit.
delete The method of claim 1,
The flow distribution unit,
Mass flow rate control device using a capacitance measurement comprising a distillation element.
The method of claim 1,
According to the control unit, the mass flow control device using the capacitance measurement further comprises a control valve for controlling the flow rate of the fluid moving on the fluid movement path is controlled.
Moving the fluid into the fluid movement tube;
Measuring a first capacitance value of the fluid using a first capacitor of the mass flow control device according to any one of claims 1, 4 to 6, 8 and 9;
Measuring a second capacitance value of the fluid using a second capacitor of the mass flow control device according to any one of claims 1, 4 to 6, 8 and 9;
Transferring first and second capacitance values measured by the first and second capacitors to a controller;
Measuring a flow rate of the fluid in the controller based on the measured first and second capacitance values; And
Including the step of controlling the flow rate of the fluid in the control unit,
Each of the first capacitor and the second capacitor,
A pair of first and second plates and a pair of third and fourth plates provided to be spaced apart and facing each other in the fluid moving tube through which the fluid is plate-shaped,
A flow rate distribution unit is provided between at least one of the first and second plates and the third and fourth plates, further comprising the step of distributing the flow of the fluid mass flow control device using a capacitance measurement Flow control method used.
The method of claim 10,
The control unit,
Capacitance for measuring the first and second capacitance values sequentially using the first and second capacitors, or simultaneously measuring the first and second capacitance values using the first and second capacitors. Flow control method using mass flow control device using measurement.

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