KR100507838B1 - Electrospray Device Having Guard Plate Of Insulated Electric Potential And Method Thereof - Google Patents

Abstract

The present invention relates to an electrostatic spraying device having an independent potential guard plate capable of controlling the generation of charged uniform microdroplets sprayed using an electrostatic sprayer and the spraying angle of the charged uniform microdroplets sprayed, and a method thereof. By installing a guard plate with an independent voltage applied to the capillary tube through which the working fluid is supplied, it is possible to stabilize the conjet mode and freely adjust the spray angle while maintaining the advantages of the conjet mode formed at the end of the capillary tube. There is a feature that can produce uniform droplets having a high charge amount.

Description

Electrostatic spraying device having independent potential guard plate and its method {Electrospray Device Having Guard Plate Of Insulated Electric Potential And Method Thereof}

The present invention relates to an apparatus and a method for controlling the generation of charged uniform microdroplets of a working fluid and the spraying angle of the working fluid to be sprayed by using an electrospray, and more particularly, to apply an independent voltage to a capillary tube. Independent dislocation guard plate which can install the guard plate to stabilize the cone-mode and control the spray angle freely while maintaining the advantage of the con-jet mode formed at the end of the capillary, and to generate uniform droplets with high charge amount The present invention relates to an electrostatic spray device having the same and a method thereof.

In general, electrostatic spray (Electrostatic Spray) is a device for generating micro droplets using a pure electrical force, has a number of advantages compared to various types of pressure spray (Spray Nozzle), droplet generator (Nebulizer) and the like.

The electrostatic spraying device is easy to manufacture a system because of the simple shape and structure of the nozzle and to generate droplets (droplets) of several hundred nanometers to tens of micrometers. In addition, the droplets have a monodisperse distribution (which keeps the particles uniformly sized and not uniformly distributed), and because the surface of the droplets is charged, the droplets do not combine well with each other and the trajectory control of the droplets is easy. have.

Recently, research on the generation and control of microdroplets of submicron size has been of great interest in relation to NT. Electrostatic spray is also used to prepare micrometallic powder by melting metal such as tin to form microdroplets and then condensing them, or to prepare high molecular weight and nonvolatile protein molecules such as insulin into microparticles of uniform size. In addition, the droplets generated by using electrostatic spray are charged, so that the application of the ceramic thin film coating or charging particles entering the electrostatic precipitator increases efficiency.

 However, in order to maximize the advantages of the electrostatic sprayer, it is necessary to control the electrostatic spray to occur in the cone-jet mode. In this electrostatic sprayer, the operating flow rate must be supplied very low to generate the cone-jet mode. Therefore, there is a disadvantage that the range of the operating voltage accordingly becomes narrow.

Hereinafter, the conventional electrostatic sprayer will be described together with the accompanying drawings.

1 is a configuration diagram showing a conventional electrostatic sprayer. As shown in FIG. 1, the conventional electrostatic spraying machine 9 includes a capillary tube 1 to which a working fluid 7 is supplied and a ground plate 5 positioned at a predetermined distance from an end of the capillary tube 1. It is composed. At this time, the insulating holder 3 is sheathed upward so that one side of the capillary tube 1 is exposed.

The conventional electrostatic atomizer 9 is configured to supply a working fluid 7 into the capillary tube 1 and apply a voltage of several kV to the capillary tube 1 so that droplets of several microns can be generated. Form a conjet-mode.

However, since the electrostatic spraying machine 9 is composed of only the capillary tube 1 and the ground plate 5 subjected to a high voltage, a conjet-mode can be formed when the distance between the ground plate 5 and the capillary tube 1 is fixed. The range of possible voltages is limited to the range of the electric field and has the disadvantage of being unable to adjust the angle at which the droplets are sprayed through the conjet-mode.

On the other hand, in order to realize a large flow rate electrostatic spraying in a limited space, each independent capillary tube 1 must be arranged in a line. In this case, the structure of the conventional electrostatic spraying machine 9 is provided by adjacent capillaries 1. Since the electric field at the end of the capillary tube 1 is mutually influenced, there is a disadvantage that it is difficult to form uniform conjet conditions in each capillary tube 1.

This is applied to the same voltage to each capillary (1), the conjet is normally formed only in the capillary (1) located in the center and there is a disadvantage that the conjet is bent outwards as the electrical interference between each capillary (1) is severe toward the edge.

Accordingly, the present invention provides an electrostatic spraying device and a method of maximizing the range of the conjet-mode generated voltage formed at the end of the capillary tube 1 and minimizing electrical interference between each capillary tube 1 in the design of the multiple capillary tube 1. .

Accordingly, the present invention has been made in view of the above-described conventional problems, and a first object of the present invention is to control the spray angles of charged uniform microdroplets sprayed through a capillary and charged uniform microdroplets sprayed. The present invention provides an electrostatic spraying device having an independent potential guard plate and a method thereof.

The second object of the present invention is to provide a guard plate to which an independent voltage is applied to the capillary electrostatic sprayer to stabilize the spray-mode and maintain the advantage of the spray-mode formed at the end of the capillary. The present invention provides an electrostatic spraying device and a method thereof, which have an independent potential guard plate that can be freely adjusted and can generate uniform droplets having a high charge amount.

The object of the present invention is a metal capillary tube to which the working fluid is supplied to the inside, a metal guard plate through which the capillary tube is exposed so as to expose the one side portion is vertically coated, the capillary tube is insulated against the guard plate to be covered Achieved by an electrostatic spraying device having an independent potential guard plate comprising an insulating member, a ground plate positioned to face one surface of the guard plate at a predetermined distance, and an insulating holder external to a capillary tube located above the guard plate. do.

The working fluid preferably has the corresponding polar ions depending on the polarity voltage applied to the capillary.

In addition, it is preferable that a separate independent voltage supply means is configured to be electrically connected to the capillary and the guard plate.

In addition, the ground plate is preferably made of a metal having the properties of the conductor so that the electric field having the polarity can be applied according to the polarity voltage applied.

And the capillary and the guard plate is preferably configured by each polar separator is electrically connected.

In addition, the above object of the present invention, the step of supplying a working fluid into the inside of the metal capillary tube, the end of the capillary tube by applying a corresponding polar voltage to the capillary tube so that the supplied working fluid can be sprayed with the selected polar ion Forming a conjet mode having a cone shape of a liquid phase and spraying the working fluid; and applying a separate external polarity voltage to the guard plate to adjust the spray angle of the working fluid sprayed into the capillary. It is achieved by the electrostatic spraying method having a potential guard plate.

The step of applying a separate external polarity voltage to the guard plate, the step of applying a polarity voltage equal to the polarity voltage applied to the capillary to the guard plate in order to reduce the spray angle of the working fluid sprayed into the capillary It is preferable.

In addition, the step of applying a separate external polarity voltage to the guard plate preferably further includes applying a voltage opposite to the polarity voltage applied to the capillary tube to increase the spray angle of the working fluid sprayed on the capillary tube.

Other objects, specific advantages and novel features of the invention will become more apparent from the following detailed description and the preferred embodiments associated with the accompanying drawings.

Hereinafter, the configuration and operation of the electrostatic spraying device having an independent potential guard plate according to the present invention will be described in detail with the accompanying drawings.

Figure 2 is a block diagram showing an electrostatic spraying device having an independent potential guard plate according to the present invention, Figure 3 is an enlarged view along line A of Figure 2, Figure 4 is a block diagram of the electrostatic sprayer according to the present invention. .

2, 3 and 4, the electrostatic spraying device 100 has a guard plate 40 to which an independent voltage is applied to the capillary 10 to which the working fluid 60 is supplied. It is a device that can be installed to control the spray angle of the working fluid (60).

In order to achieve such an electrostatic spraying device 100, it consists of three parts, which is a capillary tube 10 to which a working fluid 60 is supplied and a guard plate through which one side portion of the capillary tube 10 is exposed. 40 and a ground plate 50 positioned at a predetermined interval so as to face the guard plate 40.

In this case, the capillary 10 and the guard plate 40 are configured to be electrically connected to each other by a separate independent first voltage supply 11 and second voltage supply 41, and from each voltage supply 11, 41. It is configured to be electrically connected to the first polar separator 12 and the second polar separator 42 for separating the polarity.

At this time, the insulating member 20 is coated on one side of the capillary 10 so that the polarity voltage applied to the capillary 10 and the guard plate 40 can be blocked.

In addition, in order to block the loss of the polarity voltage flowing to the capillary 10 and the polar interference with the external polarity, the insulating holder 30 is sheathed on the capillary 10 located above the guard plate 40.

The electrostatic spraying device 100 configured as described above is sprayed with the working fluid 60 supplied according to the polarity voltage applied to the capillary 10 having the corresponding polar ions, which is a voltage having a “+” electrode through the capillary 10. This is because the negative ions dissolved in the working fluid 60 are implanted or moved to the wall surface of the capillary tube 10 and the remaining cations are pushed to the ends of the capillary tube 10.

In addition, when a high voltage is applied to the capillary tube 10, the working fluid 60 has a repulsive force of the electric force and cations acting on the liquid curved surface than the surface tension, and as shown in FIG. Where a liquid curved surface has a cone shape, and a liquid column 62 is formed at the end of the liquid cone 61 in a straight line.

At this time, the liquid column 62 is broken into droplets having a uniform fine powder shape by the disturbance of the surface waves acting on the surface of the liquid column 62 at the end, and broken droplets are sprayed at a predetermined angle.

The spray angle of the working fluid 60 broken in this way can be adjusted according to the magnitude of the polarity voltage selected of the guard plate 40.

Hereinafter, the spray angle of the working fluid according to the selected polarity voltage of the guard plate together with the accompanying drawings will be described.

5 is an exemplary view showing the spray angle of the working fluid according to the application of the polarity voltage to the capillary tube, Figure 6 is an illustration showing the spray angle of the working fluid according to the application of the same polarity voltage to the capillary tube and the guard plate, Figure 7 Is an illustration showing the spray angle of the working fluid according to the application of different polarity voltage to the capillary and the guard plate.

First, as shown in FIG. 5, the polarizing voltage is applied only to the capillary 10 without applying a voltage to the guard plate 40. At this time, it can be seen that the working fluid 60 is sprayed at a predetermined angle by an electric field formed at the end of the capillary 10. Here, the operating fluid 60 has a relatively larger spray angle than when the guard plate 40 is not installed, because the guard plate 40 replaces the role of the ground plate 50.

When the voltage having the same polarity as that of the capillary 10 is applied to the guard plate 40, the external electric field of the guard plate 40 is charged in a straight line toward the ground plate 50 as shown in FIG. 6. When the working fluid 50 is sprayed at a predetermined angle can be seen that the spray angle is reduced by the same polarity by the external magnetic field from the guard plate 40.

On the contrary, the spray angle of the working fluid 60 according to the application of different polarity voltages to the capillary 10 and the guard plate 40 is widened as shown in FIG. 7. This can be seen that the spray angle is increased to the opposite polarity due to the external magnetic field generated in the guard plate (40).

Therefore, as described through each exemplary view, the spray angle of the working fluid 60 can be selectively finely adjusted according to the magnitude of the polarity voltage selected on the guard plate (40).

Therefore, the present invention can actively control the spray angle of the working fluid 60 to prevent collision of the droplets generated in the adjacent nozzle in the precise electrostatic coating or multi-capillary tube can implement a more compact multi-capillary tube.

Hereinafter, the technical effects such as the mall will be checked in some aspects along with the attached graph.

FIG. 8 is a graph showing the range of the cone-mode applied voltage and the flow rate according to the present invention, FIG. 9 is a graph showing the range of the spray current and the flow rate of the capillary tube according to the present invention, and FIG. 10 is the conjet according to the present invention. -Graph showing the range of the mode spray angle and the flow rate, and FIG. 11 is a graph showing the range of the cone-mode droplet size and the flow rate according to the present invention.

When the applied voltage of the guard plate 40 is fixed at 0 kV, 5 kV, and 10 kV, respectively, a voltage section in which a stable cone-mode is formed according to the operating flow rate is obtained as shown in FIG. In this case, when the applied voltage of the guard plate 40 is increased more closely, it can be seen that the voltage section in which the conjet-mode is formed becomes very wide and has a continuous value.

9 shows the spray current in the section in which the cone-mode is formed. When the applied voltage of the guard plate 40 is increased or the operating flow rate is increased, a higher spray current can be obtained. Therefore, even under the same operating flow conditions, a very large spray current can be obtained by applying a high voltage to the guard plate 40.

10 shows the working fluid spray angle according to the working flow rate. As the voltage applied to the guard plate 40 increases to 0 kV, 5 kV, and 10 kV, the external electric field of the guard plate 40 acts more strongly, such that the spray angles of the automatic fluid 60 are 110 °, 33 °, and 17. Reduced to °. This can be seen that the higher the applied voltage applied to the guard plate 40, the stronger the electric force applied to the charged droplets in the axial direction, the stronger the spray angle is significantly reduced.

 11 shows the size of the droplets according to the respective flow rates when the applied voltage is 0kV, 5kV, 10kV. As a result, when the flow rate was 5 μl / min to 30 μl / min, fine droplets having a diameter of 2 μm to 16 μm were generated. Because of the same flow conditions, it can be seen that the size of the droplets generated are similar, even though the voltage applied to the ends of the guard plate 40 and the capillary 10 is different.

Hereinafter, the operation method of the electrostatic spraying device having an independent potential guard plate according to the present invention will be described in detail with the accompanying drawings.

FIG. 12 is a flowchart illustrating the electrostatic spraying method according to the present invention step by step. FIG. 13 is a first flowchart illustrating the step of applying an external polarity voltage to the guard plate of FIG. 12. FIG. 14 is a view of the guard plate of FIG. 2 is a flowchart illustrating a step of applying an external polarity voltage.

12, 13, and 14, the electrostatic spraying method is a separate external polarity voltage to the guard plate 40 to adjust the spray angle of the working fluid 60 sprayed to the capillary 10 Can be authorized.

To this end, first, a working fluid 60 having a conductive property is supplied into the metal capillary 10 (S100).

The polarity voltage is applied such that the working fluid 60 supplied to the capillary 10 can be sprayed with the selected polar ions. At this time, the polarity voltage is increased until a conjet-mode having a liquid cone shape is formed at the end of the capillary 10.

At this time, the working fluid 60 is sprayed at a predetermined angle to the droplets broken into a uniform fine powder (S200). Then, a separate external polarity voltage is applied to the guard plate 40 to selectively adjust the spray angle of the working fluid 60 (S300).

Here, if the spray angle of the working fluid 60 is to be reduced, the same polarity voltage as that applied to the capillary 10 is applied to the guard plate 40. This is because as the applied voltage applied to the guard plate 40 increases, the electric field applied to the charged droplets (grains broken by the fine powder) in the axial direction acts more strongly, and the spray angle is reduced (S310).

On the contrary, if the spray angle of the working fluid 60 is to be increased, the polarity voltage opposite to the polarity voltage applied to the capillary 10 is applied to the guard plate 40. This is because the electric field of the guard plate 40 attracts the polar ions in the charged droplet toward the guard plate 40. Therefore, the spray angle can be adjusted within the size of the guard plate 40 according to the magnitude of the polarity voltage applied (S320).

In the electrostatic spraying device having an independent potential guard plate and the method according to the present invention as described above, it can be applied to a corona discharge device or an electrostatic precipitator implemented in a similar manner and device.

As described above, according to the electrostatic spraying device having the independent potential guard plate and the method according to the present invention, if the independent potential guard plate is installed in the capillary tube, even if the distance between the capillary tube and the ground plate is constant, the range of the electrospray generation voltage It is possible to maximize, and to reduce the electrical interference between the nozzles in the manufacture of multiple nozzles to form a uniform cone jet at each nozzle, it is characterized by the high flow rate of the jet jet electrostatic spraying.

In addition, the spray angle of the sprayed droplets decreases dramatically as the voltage applied to the guard plate increases regardless of the change in the flow rate of the working fluid, thus preventing collisions between droplets generated from neighboring nozzles when installing multiple nozzles. It is characterized in that a large amount of fine droplets of uniform size can be obtained.

In addition, the independent potential guard plate can be used to obtain the cone jet mode even at a very high voltage has the advantage of obtaining a high-speed charged droplets and a high spray current.

Meanwhile, even if the independent potential guard plate is used, the droplet size does not change as compared with the case where there is no guard plate, so that the electrostatic sprayer designed in advance can be used. Therefore, the use of the independent potential guard plate can overcome the narrow range of the operating voltage range and the very small operating flow rate due to the technical limitations of the cone-jet electrostatic spraying and the electrostatic spraying technology because the spray angle can be actively controlled. There is a characteristic that can maximize the application range of the.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, various other modifications and variations may be made without departing from the spirit and scope of the invention. Accordingly, it is intended that the appended claims cover such modifications and variations as fall within the true scope of the invention.

1 is a configuration diagram showing a conventional electrostatic sprayer,

2 is a block diagram showing an electrostatic spraying device having an independent potential guard plate according to the present invention,

3 is an enlarged view taken along line A of FIG. 2;

4 is a block diagram of an electrostatic spraying machine having an independent potential guard plate according to the present invention;

5 is an exemplary view showing the spray angle of the working fluid according to the application of the polarity voltage to the capillary,

6 is an exemplary view showing the spray angle of the working fluid according to the application of the same polarity voltage to the capillary and the guard plate,

7 is an exemplary view showing the spray angle of the working fluid according to the application of different polarity voltage to the capillary and the guard plate,

8 is a graph showing the range of the conjet-mode applied voltage and flow rate according to the present invention;

9 is a graph showing the range of the spray current and flow rate of the capillary tube according to the present invention,

10 is a graph showing the range of cone-mode spray angles and flow rates in accordance with the present invention;

11 is a graph showing a range of cone-mode droplet sizes and flow rates in accordance with the present invention;

12 is a flowchart showing step by step the electrostatic spraying method according to the present invention;

FIG. 13 is a first flowchart illustrating a step of applying an external polarity voltage to the guard plate of FIG. 12;

FIG. 14 is a second flowchart illustrating a step of applying an external polarity voltage to the guard plate of FIG. 12.

<Description of the code | symbol about the principal part of drawing>

1: capillary, 3: insulated holder,

5: ground plate, 7: working fluid,

9: electrostatic spray, 10: capillary,

11: first voltage supply, 12: first polar separator,

20: insulating member, 30: insulating holder,

40: guard plate, 41: second voltage supply,

42: second polar separator, 50: ground plate,

60: working fluid, 61: liquid cone,

62: liquid column, 100: electrostatic spray device.

Claims (8)

A metal capillary 10 into which the working fluid 60 is supplied; A metal guard plate 40 through which the capillary tube 10 penetrates to expose one side thereof and is vertically coupled; An insulating member 20 coated on a portion through which the capillary tube 10 is insulated from the guard plate 40; A ground plate 50 positioned to face one surface of the guard plate 40 at a predetermined interval; In the electrostatic spraying device having an independent potential guard plate comprising a; and an insulating holder (30) external to the capillary tube (10) located above the guard plate (40), The electrostatic spraying device having an independent potential guard plate, characterized in that the working fluid (60) has a corresponding polar ion in accordance with the polarity voltage applied to the capillary (10). delete The electrostatic spraying device having an independent potential guard plate according to claim 1, wherein a separate independent voltage supply unit (11, 41) is electrically connected to the capillary tube (10) and the guard plate (40). The electrostatic spraying device having an independent potential guard plate according to claim 1, wherein the ground plate (50) is made of a metal having a property of a conductor so that an electric field having a corresponding polarity can be applied according to an applied polarity voltage. The method according to claim 1 or 3, The capillary tube 10 and the guard plate 40 are electrostatic spraying device having an independent potential guard plate, characterized in that each polar separator 12, 42 is configured to be electrically connected. Supplying a working fluid into the metal capillary 10 (S100); A working fluid is formed by applying a corresponding polar voltage to the capillary 10 so that the supplied working fluid 60 can be sprayed with a selected polar ion to form a liquid cone shape at the end of the capillary 10. Spraying (S200); And Applying a separate external polarity voltage to the guard plate 40 to adjust the spray angle of the working fluid 60 sprayed to the capillary 10 (S300); electrostatic having an independent potential guard plate comprising Spraying method. The method of claim 6, wherein the step (S300), Applying a polarity voltage equal to the polarity voltage applied to the capillary 10 to the guard plate 40 to reduce the spray angle of the working fluid 60 sprayed onto the capillary 10 (S310); Electrostatic spraying method having an independent potential guard plate, characterized in that. The method of claim 6, wherein the step (S300), Independently characterized in that the step of applying a voltage opposite to the polarity voltage applied to the capillary 10 in order to increase the spray angle of the working fluid 60 sprayed on the capillary (10); Electrostatic spraying method having a potential guard plate.