JPH0334976B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a particle mixing and dispersion method applying the principle of a contact type electric field curtain and an apparatus therefor.

[Prior Art] A contact type electric field curtain is a group of electrodes for configuring an electric field curtain, as described in Japanese Patent Publication No. 54-12667 (Method for Configuring a Contact Type Electric Field Curtain and Contact Type Electric Field Curtain Device Using the Same). A dielectric layer is placed in close proximity to or in contact with the dielectric layer, and a light object on the dielectric layer obtains a contact charge due to contact charging with the surface of the dielectric layer, and is subjected to the electrodynamic action of the electric field curtain. It is driven by repulsion from the layer.

This will be explained with reference to FIG.

By arranging mutually insulated bar-shaped or annular electric field curtain forming electrodes a in a row and applying an alternating voltage b between adjacent electrodes a, an electric force as shown by the dotted line in the figure is generated within each electrode a. An alternating unequal electric field with lines c is formed. This electrode a
Needless to say, the alternating unequal electric field with lines of electric force formed between them changes spatially in both magnitude and direction, and the direction alternates sinusoidally in time. It forms an alternating unequal electric field array. When a charged particle approaches this electric field region, it receives an alternating electric force in the direction along the electric field line c, and vibrates along the almost curved electric field line c, and every half cycle of the vibration is perpendicular to the field line c. subjected to a pulsating outward centrifugal force. As a result, the particle has an average centrifugal force
Fc acts.

In addition, the vibration phase of particles is due to vibration in a viscous medium, so that in places with a strong electric field near electrode a, the electric force is directed away from electrode a, and conversely, in places with a weak electric field far from electrode a. As a result of receiving an electric force in the direction toward the electrode a at a location, the average gradient force Fg along the electric force line c in the direction away from the electrode acts on the particle as a difference between the electric forces.

The average centrifugal force Fc is the acting force caused by the spatial change (curvature) in the direction of the line of force c, and the gradient force Fg is the acting force caused by the spatial change in the density of the line of force c (field intensity gradient). Both occur because the electric fields are unequal and alternating. As a resultant force of both, an electrodynamic reaction repulsion force Fr in the direction away from the electrode array acts on the particles.

When a dielectric layer is placed in this electric field region, particles are charged by contact charging as soon as they adhere to the dielectric layer and come to float from the dielectric layer due to the electrodynamic repulsion described above.

[Problems to be Solved by the Invention] By the way, this contact type electric field curtain device is mainly used in applications such as electrostatic precipitators, electrostatic coating booths, and electrostatic coating guns, where particles are removed or moved by repulsive force. It is currently being used.

The present inventors created the present invention by paying attention to the fact that particles cause violent disturbance motion when they are within the action area of an electric field curtain.The purpose of this invention is to electrodynamically mix or disperse particles. The object of the present invention is to provide a method for mixing and dispersing particles and an apparatus for the same.

[Means and effects for solving the problems] In order to achieve the above-mentioned object, the present invention includes the steps of: placing particles to be mixed or dispersed in a container made of a derivative;
This is a method in which the particles in the container are mixed or dispersed by placing the container in the action area of the electric field curtain,
Further, an electric field curtain forming electrode formed to surround a dielectric container containing particles to be mixed or dispersed, and an electric field curtain forming electrode for forming an alternating electric field of a standing wave or a traveling wave in the electric field curtain forming electrode. This device is equipped with a power supply device.

According to the above configuration, several types of powder or aggregated particles to be mixed or dispersed are placed in a container made of a dielectric material such as glass, and the container is exposed to the action area of the electric field curtain, so that the inside of the container is The particles of
The material is charged by contact with the container, and violently stirred within the action area of the electric field curtain, resulting in uniform mixing or dispersion.

[Embodiments] Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes an electrode body for forming an electric field curtain, which is formed into a cylindrical shape by arranging ring-shaped electrodes 2 at regular intervals while insulating them from each other. Although not shown, each electrode 2 is formed, for example, on the inner peripheral surface of a cylindrical shape made of an insulating material or embedded therein.

Conductive wires 3 and 4 are alternately connected to every other electrode 2 of this electric field curtain forming electrode body 1, and also connected to a power source 5 such as a single-phase alternating current.

To form this electric field curtain, the electrode body 1 is arranged in an inclined manner, and the carrying-in conveyor 6 is installed above it.
A carry-out conveyor 7 is arranged below.

On the other hand, particles p to be mixed or dispersed are housed in a container 8 made of dielectric material such as glass or plastic.

The particles p may be of any type as long as they can be mixed or dispersed, such as various powders to be mixed, powders in an agglomerated state to be dispersed, colloids, emulsions, slurries, etc., such as the main drug and additives of pharmaceuticals. Mixing for pharmaceutical preparations, mixing various drug powders for dispensing, mixing raw material powders for superconducting materials as applications for fine ceramics, and coloring and reinforcing plastics for injection molding. This includes mixing additives for food preparations, mixing vitamin additives with flour in the bread-making process, etc.

In addition, dispersion can be used to uniformly disperse powder particles that have aggregated in the container 8, or to uniformly disperse powder or particles in a slurry, colloid, or emulsion.

The container 8 may be of any shape such as a capsule, an ampoule, a reagent bottle, or a test tube, and its outer diameter _D8 is smaller than the inner diameter D1 of the electric field curtain forming electrode body ₁ . It is formed into a shape that can pass through the electrode body 1.

Next, the operation of this embodiment will be explained.

First, when a single-phase high voltage is applied to each electrode 2 of the electrode body 1 for forming an electric field curtain from the single-phase AC power supply device 5, an electric field curtain is formed in the electrode body 1 for forming an electric field curtain as explained in FIG. Ru.

Next, when the container 8 containing the particles p to be mixed or dispersed is dropped from the carry-in conveyor 6 into the electric field curtain forming electrode body 1, the particles p in the container 8 pass through the electric field curtain action area. As a result of each particle p being charged by contact with the container 8 and subjected to disturbance motion by the electric field curtain, complete mixing or dispersion is performed until reaching the carry-out conveyor 7.

This mixing and dispersion is carried out in many containers 8 as shown in the figure.
By sequentially passing through the electrode body 1 for forming an electric field curtain in the carrying-in conveyor 6, it is possible to carry out substantially continuously.

Next, the behavior of particles within the action area of this electric field curtain will be explained with reference to FIG.

FIG. 4 shows the behavior of the charged particles p in the container 8 when a single-phase AC voltage of 14 kV is applied between the electrodes 2.

As shown by the behavior trajectory R, the particle p falls in the direction shown by the illustrated arrow while reciprocating in the direction of the electric force lines.

In this way, each particle p in the container 8 undergoes a disturbance motion under the electrodynamic action of the electric field curtain, and as a result,
If various powders are stored in the container 8, they can be mixed uniformly, and if they are in an agglomerated state, they can be uniformly dispersed.

In addition, if a three-phase AC power source is used as the power supply device 5, a traveling wave electric field curtain will be created, and in this case, as shown in FIG. Move in the direction of the arrow shown. In the case of the electric field curtain forming electrode body 1 shown in FIG. 1, the traveling wave may be directed in the direction in which the container 8 falls, or the power source may be connected so that the traveling wave is directed upward.

FIGS. 2 and 3 show other embodiments of the present invention.

In FIG. 2, the electrode 2 is formed of rod-shaped electrodes, which are arranged in a cage shape in the circumferential direction to form the electrode body 1 for forming an electric field curtain. Although this electrode body 1 is not shown, each electrode 2 is connected to a single-phase or three-phase AC power source. Other container 8
Using a reagent bottle or the like, open the stopper 9, add the powder particles p to be mixed or dispersed, close the stopper 9, and insert the container 8 into the electrode body 1 for forming an electric field curtain by inserting it into the chain double-dashed line shown in the figure. Particles can be mixed and dispersed by adding as shown in . In addition, FIG. 3 shows the formation of an annular electric field curtain forming electrode body 1.
A container 8 is formed from a test tube inside the container 8, and after accommodating the particles P therein, the stopper 9 is closed, and mixing and dispersion are performed in the same manner as in the embodiment shown in FIG.

In the above-mentioned embodiment, an example was explained in which the electrode body 1 for forming an electric field curtain was formed into a cylindrical shape, but the electrode body 1 may be formed into a flat plate shape or a curved shape. Further, although an example has been described in which a single-phase or three-phase AC power source is used as the power supply device 5, a power source in which a DC power source is superimposed on these power sources may also be used. In addition, although an example has been described in which the container 8 containing the particles p is passed through or placed inside the electrode body 1 for forming an electric field curtain, the electric field can be applied by moving the electrode body 1 side for forming an electric field curtain. It may also be made to face the area.

[Effects of the Invention] As is clear from the above explanation, the present invention exhibits the following excellent effects.

(1) By placing a dielectric container in the area of action of the electric field curtain, the particles inside the container can be charged by contact and uniformly mixed and dispersed.

(2) Unlike conventional mechanical mixing and dispersion, each particle is mixed and dispersed in a disturbed state, allowing for more complete mixing and dispersion.

[Brief explanation of drawings]

FIG. 1 is a front sectional view showing an embodiment of the present invention;
Figures 2 and 3 are perspective views showing other embodiments of the present invention, Figures 4 and 5 are explanatory diagrams showing the behavior of particles in the present invention, and Figure 6 shows the principle of electric field curtain. It is a diagram. In the figure, 1 is an electrode body for forming an electric field curtain, 2 is an electrode, 5 is a power supply device, 8 is a container, and p is a particle.

Claims (1)

[Claims] 1. Particles to be mixed or dispersed are placed in a dielectric container, and the container is placed in the action area of an electric field curtain to mix or disperse the particles in the container. Method of mixing and dispersing particles. 2. A dielectric container containing particles to be mixed or dispersed, an electric field curtain forming electrode body formed to surround the dielectric container, and a fixed electrode for each electrode of the electric field curtain forming electrode body. 1. A particle mixing/dispersing device comprising a power supply device for applying a high voltage in the form of a current wave or a traveling wave.