KR20170090106A - Jet Mill for Making Nano Powder by Use of the Coanda Effect - Google Patents

Abstract

The present invention relates to a jet mill for producing nano powder using the Coanda effect.
The jet mill for manufacturing nano powder using the Coanda effect of the present invention has a disk-like hollow portion 10 formed therein, and an inlet 11 through which an object to be pulverized flows is formed at one side of the hollow portion 10 A plurality of collision plates 20 are disposed inside the cavity 10 to be crushed by crushing the object to be crushed into the inlet 11. The collision plate 20 is struck at the other side of the cavity 10, And a discharge port (12) through which pulverized nano powder is discharged are formed in the cavity (10), wherein a plurality of radial jet mills are installed in the cavity (10) with respect to the center of the cavity (10) 31 and the outer circumferential surface 32 are spaced apart from the inner wall surface 10a and the outer wall surface 10b of the cavity 10 to form an inner cavity 10 between the inner circumferential surface 31 and the inner wall surface 10a of the cavity 10, And an outer cavity 32 is formed between the outer peripheral surface 32 and the outer wall surface 10b of the hollow portion 10, And a plurality of partition walls 30 are formed between the adjacent side wall surfaces 35 to form a connection passage portion 36 connecting the inner cavity portion 33 and the outer cavity portion 34 to each other. The inlet port 11 is connected to the inner cavity 33 and the outlet port 12 is connected to the outer cavity 34 and the partition walls 30 are in contact with each other, A compressed air jetting port 40 for jetting high-pressure compressed air to the object to be ground is formed along the moving direction of the object to be crushed against the plate 20. The partitioning walls 30 are formed on the inner side of the compressed air jetting port 40 side The curved portion 50 is formed by curving the corners rounded so that the pulverized powder is hit by the impact plate 20 due to the Coanda effect and the pulverized powder is classified by weight so that the powder having a small weight passes through the connecting passage portion 36 To move to the outer cavity 34, and the relatively heavy powder causes the inner cavity < RTI ID = 0.0 > It characterized in that is adapted to move along a 33.
According to the present invention, a connecting passage part is formed so as to divide the cavity part into an outer cavity and an inner cavity part, and from the inner cavity part to the outer cavity part in the course of collision with the impingement plate to move the crushed powder along the inner cavity part, Pressure compressed air is separately supplied to the side of the curved portion by curving the corner portions of the partition wall adjacent to the impingement plate so as to move the fine powder through the connection passage to the outer cavity portion by utilizing the centrifugal force and the coanda effect at the curved portion, The large powder continuously circulates the inner cavity so that the powder sorting and crushing efficiency can be maximally improved.

Description

[0001] The present invention relates to a jet mill for making a nano powder using a Coanda effect,

[0001] The present invention relates to a jet mill for producing nano-powder, and more particularly to a jet mill for producing nano powder by pulverizing powder by collision with an impingement plate, classifying the powder by weight by centrifugal force using a Coanda effect, To a jet mill for producing nano powder using a Coanda effect, which is capable of separately dividing the powders so as to minimize the necessity of separate sorting operations.

Jet mill (JET MILL, grinding and dispersing apparatus) refers to a device for grinding a pulverized material in a high-speed air stream and crushing the pulverized material placed on the air stream to obtain ultrafine powder.

As an example of a ground product, the superfine clamshell is referred to as microcrystalline particles, which are used as pharmaceuticals.

Most of microcrystal particles formed through a jet mill are formed most in the range of 1 to 10 mu m, and among them, those having a particle size of about 3 mu m are most suitable.

Therefore, it can be said that the milling efficiency of the jet mill is higher as the grain size is increased by one milling step.

There are various types of jet mills, but among them, a swirl flow type is widely used in which airflow is supplied through nozzles to form airflow circulating in the pulverizing chamber.

In FIG. 3, the operation state of the swirling flow type jet mill is shown in a schematic manner.

In the structure of the figure, a disk-shaped hollow portion 10 is formed inside, and an inlet 11 through which the object to be ground flows is formed at one side of the hollow portion 10, A plurality of collision plates 20 are disposed on the other side of the hollow portion 10 so as to be collided with the collision plate 20 so that the collided nanoflowers 120 ) Are formed.

This structure causes the object to be grounded to flow into the cavity portion 10 through the inlet 11 and move along the cavity portion 11 by the injection of the compressed air.

At this time, the injection direction becomes a direction in which the compressed air can naturally be turned, thereby forming a swirl flow.

In this swirling flow, the pulverized material is hit by the impact plate 20 provided on the wall surface, and is crushed by mutual collision.

As a result, when the pulverized material is pulverized and the particle diameter is reduced, since the centrifugal force due to the swirling flow is more affected by the discharge pressure, the pulverized material and compressed air having a particle size smaller than a certain particle diameter are discharged through the passage 120.

Since the swirl flow type jet mill is pulverized by the friction between the pulverized material and the impinging impact on the impinging plate, the pulverizing device or the water mill using water, There is an advantage that the risk of mixing the pure products is remarkably low and an additional process of separating the pulverized material (the blade or the water) and the pulverized material after the pulverization is performed is unnecessary.

Further, there is an advantage that it is possible to crush smaller particles than other conventional crushing apparatuses in such a manner that the crushing is performed through collision between the crushed materials.

However, the prior art has a problem that the centrifugal separation process and the recirculation process are required due to insufficient effect in the uniformity portion of the pulverization.

As a technique for solving such a problem, in a "jet mill" (Korean Patent Registration No. 10-1511978, Patent Document 1), flow in a vertical direction is generated by a nozzle formed by a nozzle, To increase the possibility of collision between water and to increase the classification efficiency by minimizing the leakage from the side wall to the center by providing inclination to the cavity.

However, when the upper wall surface is inclined, the flow of the swirling flow itself is blocked. As shown in Patent Document 1, the present invention can be applied to a structure in which a plurality of nozzles are installed. However, The flow of the swirling flow is disturbed, and the swirling flow rate is lowered, thereby seriously lowering the grinding efficiency.

KR 10-1511978 (April 5, 2014)

A jet mill for manufacturing nano powder using the Coanda effect of the present invention is a jet mill for manufacturing nano powder which is divided to be divided into an outer cavity and an inner cavity, A connecting passage portion extending from the inner cavity portion to the outer cavity portion in the process of moving the water along the inner cavity portion is formed so that the corner portion of the partition wall adjacent to the impingement plate is curved so as to separately supply compressed air of high pressure to the curved portion side, The centrifugal force and the Coanda effect are utilized to allow the fine powder to move to the outer cavity via the connection passage and the large size powder continuously circulates in the inner cavity so that the classification and crushing efficiency of the powder can be maximally improved.

In order to solve the above-mentioned technical problem, a jet mill for manufacturing nano powder using the Coanda effect of the present invention is provided with a disk-shaped hollow portion 10 inside thereof, and on the one side of the hollow portion 10, A plurality of impingement plates 20 are disposed inside the cavity 10 in order to crush the object to be crushed and introduced into the inlet 11 to be crushed, And a discharge port (12) through which the pulverized nano powder is discharged is formed on the other side of the cavity plate (10). The jet mill for manufacturing nano powder is characterized in that the cavity The inner circumferential surface 31 and the outer circumferential surface 32 are spaced apart from the inner wall surface 10a and the outer wall surface 10b of the hollow portion 10 so that the inner circumferential surface 31 and the hollow portion 10 are formed inwardly, An inner cavity portion 33 is formed between the inner wall surfaces 10a, An outer cavity 34 is formed between the cavity 32 and the outer wall surface 10b of the cavity 10 and an inner cavity 33 and an outer cavity 34 are connected between the adjacent side walls 35 A plurality of partition walls 30 are formed in which the connection passage portion 36 is formed and the inlet port 11 is connected to the inner cavity portion 33 and the outlet port 12 is connected to the outer cavity portion The partition walls 30 are formed with a compressed air injection port 40 for spraying high pressure compressed air to the object to be crushed along the moving direction of the object to be crushed against the impact plate 20 Each of the partition walls 30 is formed with a curved portion 50 whose inner edge on the side of the compressed air injection port 40 is curved in a rounded shape so that the pulverized powder is hit by the impact plate 20 by the Coanda effect, The powder of small weight is moved along the connecting path portion 36 along the curved portion 50 to the outer cavity portion 34 And, the relatively large weight of the powder is characterized in that is adapted to move along the inner joint portion 33.

In this configuration, the connection passage portion 36 is characterized in that the inner diameter of the inner cavity portion 33 side is smaller than the inner diameter of the outer cavity portion 34 side.

The compressed air injection port (40) is formed to be inclined from the inner cavity (33) so as to have an inclination angle of less than 90 degrees.

According to the present invention, a connecting passage part is formed so as to divide the cavity part into an outer cavity and an inner cavity part, and from the inner cavity part to the outer cavity part in the course of collision with the impingement plate to move the crushed powder along the inner cavity part, Pressure compressed air is separately supplied to the side of the curved portion by curving the corner portions of the partition wall adjacent to the impingement plate so as to move the fine powder through the connection passage to the outer cavity portion by utilizing the centrifugal force and the coanda effect at the curved portion, The large powder continuously circulates the inner cavity so that the powder sorting and crushing efficiency can be maximally improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view showing a jet mill for producing nano powder using the Coanda effect of the present invention. FIG.
FIG. 2 is a schematic view showing movement, crushing and classification of powder around a curved portion in the present invention. FIG.
3 is a schematic view showing a conventional jet mill for powder production;

Hereinafter, a jet mill for manufacturing nano powder using the Coanda effect of the present invention will be described in detail with reference to the accompanying drawings.

As described above, the jet mill for manufacturing nano powder using the Coanda effect of the present invention has a disk-shaped hollow portion 10 formed therein. An inlet 11 through which the object to be pulverized flows into the hollow portion 10, And a plurality of collision plates 20 are disposed inside the cavity 10 to be crushed by crushing the object to be crushed into the inlet 11. The collision plate 20 And a discharge port 12 through which the pulverized nano powder is discharged.

As shown in FIGS. 1 and 2, the jet mill for producing nano powder using the Coanda effect of the present invention is characterized in that a partition wall body 30 is provided unlike the conventional one.

3, a plurality of partition walls 30 are radially provided inside the cavity 10 as shown in FIG. 1, with respect to the center of the cavity 10.

The partition wall 30 defines an inner cavity 33, which is a space in which the inner circumferential surface 31 is spaced apart from the inner wall surface 10a of the cavity 10.

The outer peripheral surface 32 of the partition wall body 30 forms an outer cavity portion 34 in a space separated from the outer wall surface 10b of the cavity portion 10.

That is, as shown in FIG. 1, the cavity portion 10 is divided into an inner cavity 33 and an outer cavity 34 by the partition wall 30.

At this time, as shown in the figure, the inlet 11 through which the object to be ground flows is formed to be connected to the inner cavity 33.

The object to be ground may be configured to be introduced at a time through one inlet as shown in FIG. 1, or may be configured in the form of an ejector type so that the object to be ground is sucked by the minus pressure on the jet port of the compressed air .

Alternatively, the object to be ground may be introduced into the inlet 11 of the drawing, and a plurality of compressed air injection nozzles may be installed radially in the cavity 10.

The discharge port 12 is connected to the outer cavity 34 so that the pulverized material circulating on the outer cavity 34 can be discharged.

The partition walls 30 are spaced apart from each other in a radial direction and are provided between the sidewall surfaces 35 of the adjacent partition walls 30 so as to form a connection passage portion 34 connecting the inner cavity portion 33 and the outer cavity portion 34. [ (36) are formed.

1, each of the partition walls 30 has a compressed air injection port 40 for spraying high-pressure compressed air to the object to be crushed along the direction of movement of the object to be crushed against the impingement plate 20, Is formed.

Particularly, each of the partition members 30 is characterized in that a curved portion 50 is formed in which the inner edge of the compressed air injection port 40 side is curved roundly.

The powder is crushed by the impact plate 20 due to the Coanda effect so that the pulverized powder is classified by weight so that the powder having a small weight flows along the curved portion 50 along the connecting passage portion 36 to the outer cavity portion 34 And the relatively heavy powder is allowed to move along the inner cavity portion 33. As shown in Fig.

In order to effectively generate the coanda effect, the inner diameter of the connecting cavity portion 36 on the side of the inner cavity portion 33 is preferably smaller than the inner diameter of the outer cavity portion 34, The compressed air injection port 40 is formed to be inclined from the inner cavity 33 at an oblique angle of less than 90 degrees.

Hereinafter, major effects of the present invention will be described with reference to Figs. 1 and 2. Fig.

In the inner cavity portion 33, the object to be ground is moved in a pivoting manner by the inflow of the compressed air. At this time, the object to be ground is crushed to a smaller size while being hit by the impact plate 20 together with each other.

At this time, compressed air is injected from the compressed air injection port 40 at an angle inclined to the inner cavity 33 in the process of continuously moving the objects to be crushed and having a smaller particle size along the inner cavity 33 The object to be ground is moved toward the impingement plate 20 side of the adjacent partition wall 30 in the turning direction.

Since the curved portion 50 is formed on the inner edge side of the partition wall 30 as shown in the figure, the object to be ground is grasped by the Coanda effect, A flow toward the connection passage portion 36 is formed together with the connection portion 50.

At this time, since the jetting pressure injected from the compressed air jetting port 40 is higher than the pressure to move on the curved portion 50 according to the Coanda effect, and the centrifugal force acts on the curved portion 50, The particles that are smaller in weight are subjected to the force of the centrifugal force to flow along the curved portion 50 toward the connection passage portion 36. In this case, .

Therefore, the basic particle size classification is performed inside without a separate separator or centrifuge connected to the outside.

In addition, the micronized particles flow into the connection passage portion 36 each time they pass through the partition walls 30, and are crushed by the impingement plate 20 while being rotated only in the inner cavity portion 33 Therefore, the efficiency of pulverization also increases.

Therefore, the demand of the centrifugal separator installed in conjunction with the jet mill can be minimized.

10: cavity portion 10a: inner wall surface
10b: outer wall surface 11: inlet
12: outlet 20: collision plate
30: partition wall body 31: inner peripheral surface
32: outer peripheral surface 33: inner cavity
34: outer cavity portion 35: side wall surface
36: connecting passage portion 40: compressed air nozzle
50:

Claims (3)

Shaped cavity 10 is formed in the cavity 10 and an inlet 11 through which the object to be ground flows is formed at one side of the cavity 10 and an inlet 11 is formed inside the cavity 10 A plurality of impingement plates 20 are disposed on the other side of the cavity portion 10 to form a discharge port 12 through which the pulverized nano powder is struck by the impact plate 20 In a jet mill for manufacturing a nano powder,
The inner circumferential surface 31 and the outer circumferential surface 32 are formed in the cavity 10 in the radial direction with respect to the center of the cavity 10, An inner cavity 33 is formed between the inner circumferential surface 31 and the inner wall surface 10a of the cavity 10 so as to be spaced apart from the outer circumferential surface 32 and the outer wall surface 10b And a connecting passage portion 36 connecting the inner cavity portion 33 and the outer cavity portion 34 between adjacent side wall surfaces 35 is formed between the adjacent side wall surfaces 35. [ (30) is provided,
The inlet 11 is connected to the inner cavity 33,
The outlet 12 is connected to the outer cavity 34,
The partition walls 30 are formed with compressed air ejection openings 40 for ejecting high-pressure compressed air to the object to be crushed along the moving direction of the object to be crushed against the impingement plate 20,
Each of the partition walls 30 is formed with a curved portion 50 whose inner edge on the side of the compressed air injection port 40 is curved in a rounded shape so that the pulverized powder is hit by the impact plate 20 by the Coanda effect, The small weight powder is allowed to move along the connecting path portion 36 along the curved portion 50 to the outer cavity portion 34 and the relatively heavy powder is allowed to move along the inner cavity portion 33 Features,
Jet mill for nano powder manufacturing using Coanda effect.
The method according to claim 1,
Wherein the connection passage portion (36) has an inner diameter at the side of the inner cavity portion (33) smaller than an inner diameter at the side of the outer cavity portion (34)
Jet mill for nano powder manufacturing using Coanda effect.
The method according to claim 1,
Characterized in that the compressed air injection port (40) is formed so as to be inclined from the inner cavity (33) to have an inclination angle of less than 90 degrees.
Jet mill for nano powder manufacturing using Coanda effect.

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