JPH0852376A - Collision type airflow grinder - Google Patents

Abstract

PURPOSE:To use effectively grinding energy and to attempt highly efficient grinding by a machine wherein the inner peripheral face of an accelerating pipe connected with a compressed-air feeding nozzle and with a feeding hole for a substance to be ground is formed so as to satisfy a specified equation and a collision member for grinding the substance to be ground is provided and an compressed gas with a proper pressure is used. CONSTITUTION:A compressed-air feeding nozzle 2, an accelerating pipe 3 connected with the feeding nozzle 2 and with a feeding hole 1 for a substance to be ground and a collision member for grinding the substance to be ground are provided. In this grinder, the accelerating pipe 3 which satisfies the equation, Ltan(theta/2)>=L1tan(theta1/2)>(1/2)Ltan(theta/2) is provided (wherein, the effective length of the accelerating pipe 3 is L; a distance wherein the distance from a throat part 2a is 1/2 of the effective length L is L1; the diffluent angle of the accelerating pipe is theta; two-fold of an angle formed by a line 11 connecting a point 3a on the inner peripheral face of the accelerating pipe with a distance of L1 along the common central line C form the throat part 2a and a point on the inner peripheral face of the throat part 2a and the common central line C is theta1).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision type airflow pulverizer equipped with a pressure reducing portion supply type pulverization nozzle using a jet jet, and more specifically, a toner or a colored resin for toner used for image formation by electrophotography. The present invention relates to a collision type airflow crusher suitable for producing powder.

[0002]

2. Description of the Related Art A collision-type airflow crusher using a jet jet supplies an object to be crushed into a jet jet, collides the object with a collision member, and crushes it by its impact force. A general structure of such a collision type airflow crusher will be described with reference to FIG. FIG. 4 is a flow sheet of a crushing / classifying process in which a collision type airflow crusher and a classifier are combined, and the collision type airflow crusher is shown in a schematic vertical sectional view.

In this collision type air flow pulverizer, a collision member 4 is provided so as to face the acceleration pipe outlet 8 of the acceleration pipe 3 connected to the compressed gas supply nozzle 2, and the high speed air flow 14 which is a jet jet by the acceleration pipe 3 is generated. The object to be crushed 6 is moved by the flow, and the acceleration tube 3
Is sucked into the accelerating pipe 3 from the crushed object supply port 1 provided in the middle of the crushing process, and is injected together with the high-speed air flow 14 into the crushing chamber 7 to collide with the collision surface 9 of the collision member 4 and crushed by the impact force. To do.

Usually, in order to crush the material to be crushed 6 to a desired particle size, the classifier 1 is provided between the material supply port 1 and the discharge port 5 of the material to be crushed.
3 is deployed to form a closed circuit. In this case, the classifier 13
After the classification by, the coarse powder is sent to the object to be crushed supply port 1 through the return path 11 to perform the crushing, and the crushed material 1
0 is returned from the outlet 5 to the classifier 13 and classified again, and the fine powder is obtained via the path 12 to obtain a desired finely pulverized product.

[0005]

However, in the conventional collision type airflow crusher having the decompression section supply type crushing nozzle, the accelerating tube 3 is effective in the injection nozzle constituted by the compressed air supply nozzle 2 and the accelerating tube 3. The relationship between the length L and the spread angle θ (see FIG. 4) is not sufficiently appropriate, and under normal pressure, the jet jet flow when passing through the acceleration tube 3 is Sufficient expansion cannot be obtained on the wall surface and the engine stalls during passage. Further, if the effective length L is short, the acceleration distance becomes insufficient, and if the effective length L is too long, pressure loss occurs and deceleration causes stall.

In order to solve such a problem, the divergence angle θ of the accelerating tube 3 is set to 7 ° in JP-A-3-26349, JP-A-3-26350, and JP-A-3-30845. An injection nozzle defined within a range of up to 9 ° has been proposed, but it has not always been possible to obtain sufficient pulverization processing capacity.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to make effective use of the energy of a compressed gas to improve the crushing capacity of a collision type air flow. To provide a crusher. The crusher of the present invention, in order to achieve this object,
The structure of the injection nozzle is improved as follows.

[0008]

The structure and operation of the present invention will be described more specifically below with reference to FIGS. The collision type airflow crusher of the present invention ejects from the acceleration tube 3 into the crushing chamber 7 after the depressurization part supply acceleration pipe 3 that accelerates the transportation of the crushed object 6 through the crushed object supply port 1 by the high-speed airflow. The collision surface 9 (FIG. 4) for crushing the crushed object 6 by the impact force.
) Is provided and the high pressure gas ejected from the compressed gas supply nozzle 2 passes through the accelerating tube 3 and becomes supersonic due to ideal adiabatic expansion. Therefore, according to the collision type airflow crusher of the present invention,
It is possible to efficiently use the high-speed airflow to pulverize the object 6 to be pulverized to the order of several μm.

FIG. 1 is a schematic vertical sectional view of a compressed gas supply nozzle 2 and an accelerating pipe 3 provided in a collision type airflow crusher according to claims 1 to 6. That is, the collision type airflow crusher according to claim 1 is an acceleration tube 3 having a compressed gas supply nozzle 2 and a crushed object supply port 1 connected to the supply nozzle 2.
And a collision member 4 for colliding and crushing the crushed object 6.
In the crusher equipped with, for the acceleration tube 3, the effective distance along the common center line C of the supply nozzle 2 and the acceleration tube 3 from the throat portion 2a of the compressed gas supply nozzle 2 to the effective outlet portion 3b of the acceleration tube 3. (The effective length of the accelerating tube 3) is L, and for the accelerating tube 3, the distance from the throat 2a is 1/2 the effective distance L, and the distance along the common center line C is L ₁ . As for the inner peripheral surface of the acceleration tube 3, the angle formed by the line 1 connecting the throat portion 2a and the effective outlet portion 3b and the common center line C is doubled (the divergence angle of the acceleration tube (3)) is θ. Furthermore, regarding the inner peripheral surface of the acceleration tube 3, a point 3a on the inner peripheral surface of the acceleration tube 3 whose distance from the throat 2a along the common center line C is L ₁
Let θ ₁ be the angle between the common centerline C and the line l ₁ that connects the point on the inner peripheral surface of the throat 2 a with the inner peripheral surface of the accelerating tube 3 as It is formed so that the relational expression [1] is satisfied.

[0010]

[Number 1] Ltan (θ / 2) ≧ L 1 tan (θ 1/2)
> (1/2) Ltan (θ / 2)

In the collision type air flow crusher having such an accelerating nozzle, the crushed material 6 supplied from the crushed material supply port 1 to the accelerating pipe 3 is conveyed by the air flow ejected from the compressed gas supply nozzle 2. It In this case, the compressed gas supply nozzle 2
The airflow reaching the sonic velocity in the throat portion 2a is accelerated to supersonic velocity by the angle θ ₁ , and the gas velocity can be maintained by the angle θ ₂ (see FIG. 1). The angle θ ₂ is, as shown in FIG. 1, a point 3 a on the inner peripheral surface of the acceleration tube 3 whose distance from the throat 2 a along the common center line C is L ₁ and the effective outlet portion 3
The angle between the line l ₂ connecting the line b and the common center line C is doubled.

In the collision type airflow crusher according to claim 2, the acceleration pipe 3 according to claim 1 has a diameter D of the throat portion 2a, an effective length L of the acceleration pipe 3, and a spread angle θ of the acceleration pipe 3. Between
The relational expression shown in the following [Equation 2] holds and θ is 1
It is characterized in that it has a smooth spread shape in which L is in the range of 8D to 30D at 0 to 7 °.

[0013]

[Expression 2] 1.8D ≧ Ltan (θ / 2) ≧ 0.13D

A collision-type airflow crusher according to a third aspect is the collision member according to the second aspect, wherein the crusher has a shape in which the jets from the accelerating pipe 3 generate a non-uniform flow and collide while being dispersed.
₂ (see FIG. 6) and uses a compressed gas having a pressure of 0.7 MPa or more, and the acceleration tube 3 has a throat portion 2a.
, The effective length L of the accelerating tube 3 and the divergence angle θ of the accelerating tube 3 satisfy the relational expression shown by the following [Equation 3], and when the angle θ is 2 ° to 7 °, L Is in the range of 10D to 30D, and has a gentle spread shape.

[0015]

## EQU00003 ## 1.8D ≧ Ltan (θ / 2) ≧ 0.19D

According to the study by the present inventors, when crushing the crushed object 6 having low crushability in the crusher of claim 3, the pressure in the compressed gas supply nozzle 2 is set to 0.7 MPa or more. It has been confirmed that the above is effective in improving the pulverizability and reducing the amount of fine powder generated by over-pulverization.

A collision-type airflow crusher according to a fourth aspect is the collision member 4 according to the second aspect, wherein the crusher has a shape in which the jets from the accelerating pipe 3 generate a non-uniform flow and collide while being dispersed.
₂ (see FIG. 6) and uses a compressed gas having a pressure of 0.7 MPa or less, and the acceleration tube 3 includes a throat portion 2a.
, The effective length L of the accelerating tube 3 and the divergence angle θ of the accelerating tube 3 satisfy the relational expression shown in the following [Equation 4], and when the angle θ is 2 ° to 7 °, L Is in the range of 8D to 25D, and has a smooth spread shape.

[0018]

(4) 1.2D ≧ Ltan (θ / 2) ≧ 0.19D

According to the study by the present inventors, in the crusher of claim 4, when the crushed object 6 having relatively good crushability is crushed, the pressure in the compressed gas supply nozzle 2 is set to 0.7.
It has been confirmed that setting to MPa or less is effective for reducing the amount of fine powder generated by over-pulverization, and that the amount of molten agglomerates produced by the heat of pulverization can be reduced.

A collision-type airflow crusher according to a fifth aspect is the collision member 4 according to the second aspect, wherein the crusher directly collides with the jet from the acceleration tube 3 without causing any uneven flow or dispersion. ₁ (see FIG. 5), the acceleration tube 3 has a throat 2a.
, The effective length L of the accelerating tube 3 and the divergence angle θ of the accelerating tube 3 satisfy the relational expression shown in the following [Equation 5], and when the angle θ is 1 ° to 5 °, L Is in the range of 8D to 30D, and has a smooth spread shape.

[0021]

[Expression 5] 0.78D ≧ Ltan (θ / 2) ≧ 0.13D

According to the study by the present inventors, the crushing ability of the crusher of claim 5 is slightly lower than that of the crusher of claims 3 and 4, but it is effective in preventing the generation of fine powder due to over-milling. Yes,
It has been confirmed that high-efficiency crushing with a high yield is possible.

In the pulverizer shown in FIG. 2, the effective outlet portion 3b at the end of the accelerating tube 3 is provided with a diverging outlet portion 3c to rapidly enlarge the accelerating tube 3 outlet portion. The angle set by the throat portion 2a of the compressed gas supply nozzle 2 and the effective outlet portion 3b of the acceleration tube 3 is not the angle set by the throat portion 2a and the spread outlet portion 3c. The accelerating tube 3 of FIG. 2 is provided with a portion that is abruptly expanded before the effective length L portion, but the effect of the present invention can still be obtained.

FIG. 7 shows the definition of the throat 2a and the effective distance L. 1 to 3, the throat portion 2a shows a joint surface between the acceleration tube 3 and the compressed gas supply nozzle 2.
The throat 2a itself refers to the narrowest part between the compressed gas supply nozzle 2 and the acceleration tube 3. Therefore, the throat 2a is connected to the supply nozzle 2
Is not limited to the joint boundary portion between the supply nozzle 2 and the acceleration tube 3,
It may exist inside both of the acceleration tubes 3. Further, when the value of the narrowest part showing the throat 2a has the same size and width in the longitudinal direction, the effective distance L of the acceleration tube 3 is from the position of the throat 2a closest to the exit 8 of the acceleration tube 3 to the exit 8. (See FIG. 7).

The diameter D of the throat 2a and the effective distances L and L ₁ will be supplementarily described with reference to FIG. In FIG. 8, the compressed gas supply nozzle 2 is made long and the divergence angle θ in the compressed gas supply nozzle 2 is made extremely small. In this case, the acceleration effect does not exceed the effect of the acceleration tube 3 shown in FIG. The diameter D is the diameter of the narrowest part of the acceleration tube 3 or the compressed gas supply nozzle 2. Effective distance L
Regarding, regarding the extension line l _{3 of the} contour line representing the tapered inner peripheral surface of the accelerating tube 3 and the intersection point of the straight line l _{4 which is in contact} with the narrowest portion and is parallel to the common center line C, the intersection point is 2b. The distance from 2b to the effective outlet portion 3b of the acceleration tube 3 along the common center line C. Further, L ₁ is a distance along the common center line C, which is 1/2 the effective distance L from the intersection 2b.

FIG. 3 is a schematic vertical sectional view of the compressed gas supply nozzle 2 and the accelerating pipe 3 provided in the crusher of claim 1.
That is, the accelerating tube 3 is formed by arranging the annular bodies 3d and 3e in the longitudinal direction of the accelerating tube 3 and connecting them so as to be separable from each other. In the collision type air flow pulverizer, the material to be pulverized is conveyed to the accelerating pipe outlet 8 by the high-pressure gas ejected from the compressed gas supply nozzle 2. The material to be pulverized has a true specific gravity, a bulk density, and a particle size distribution depending on the application and type. Is different. In order to form a crushing air flow suitable for different crushed objects, the accelerating tube according to claim 6 is configured so that the combination of θ ₁ and θ ₂ is freely configured, and the crushed object is accelerated at high speed in an optimum state. The accelerating tube 3 is configured so that it can be divided and combined so that the expansion shape of the accelerating tube 3 can be easily formed. In addition,
In FIG. 3, two annular bodies are combined to form the acceleration tube 3, but three or more annular bodies may be combined.

As described above, the collision type airflow crusher of the present invention is provided with the accelerating tube and the collision member having the predetermined characteristics, and by using the compressed gas of an appropriate pressure, the crushing energy is effectively used. This enables high-efficiency crushing.

[0028]

Embodiments of the present invention will be described below. Example 1 (according to claim 3) Polyester resin 100 parts by weight Phthalocyanine pigment 8 parts by weight Toner pigments having the above formulation were mixed in a mixer, and the mixture was melt-kneaded at about 200 ° C. in an extruder. Then, it was cooled and solidified, and the cooled product of the melt-kneaded product was roughly crushed into particles of 200 to 2000 μm by a hammer mill. This coarsely pulverized material was used as an object to be pulverized and pulverized by the pulverizer and flow shown in FIG. A fixed wall air classifier was used as a classifier for classifying the crushed powder into fine powder and coarse powder.

Compressed gas supply nozzle 2 of collision type air flow crusher
Compressed air having a pressure of 0.882 MPa is introduced from the pulverized material supply port 1 shown in FIG. 1 to the pulverized material 6 at 34 kg / Hr.
Supplied at the rate of The obtained pulverized product 10 was sent to the classifier 13, fine powder was removed as classified powder, and coarse powder was again charged into the accelerating pipe 3 as the pulverized product 6 together with the powder material from the pulverized product supply port 1.

The accelerating tube 3 is indicated by D in FIG.
= 9 mm, L = 25 D, θ = 7 °, θ ₁ = 12.8 °,
θ ₂ = 1 ° is used, and as the collision member, the collision member 4 ₂ shown in FIG. Although it was carried out, a large amount of molten agglomerates were generated on the way, and the experiment could not be continued. Even if the supply amount of the pulverized material was reduced, it was not effective in preventing the generation of molten agglomerates.

Example 2 (according to claim 4) The same pulverized material 6 as in Example 1 was pulverized with a classifier and a flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air with a pressure of 0.686 MPa was introduced from the compressed gas supply nozzle 2 of the collision type air flow crusher, and
34 kg / H of crushed material 6 from crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

The accelerating tube 3 is indicated by D in FIG.
= 9 mm, L = 18.5 D, θ = 5 °, θ ₁ = 8.9.
, Θ ₂ = 1 °, and the collision member 4 ₂ shown in FIG. 6 is used as the collision member, in which the jet flow from the accelerating tube 3 causes uneven flow and collides while being dispersed. Continuous operation was performed for an hour. As a result, the volume average particle diameter is 9 μm.
A fine powder having a particle size of 4 μm or less and 14% of the total amount of fine powder generated was obtained.

Example 3 (according to claim 5) The same pulverized material 6 as in Example 1 was pulverized with a classifier and a flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air with a pressure of 0.686 MPa was introduced from the compressed gas supply nozzle 2 of the collision type air flow crusher, and
30 kg / H of the crushed material 6 from the crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

The accelerating tube 3 is indicated by D in FIG.
= 9 mm, L = 18.5 D, θ = 3.5 °, θ ₁ = 6
And θ ₂ = 1 ° are used, and as the collision member, a collision member 4 ₁ shown in FIG. 5 having a shape in which the jet from the accelerating tube 3 directly collides without any uneven flow or dispersion is used. Then 1
Two hours of continuous operation was performed. As a result, the volume average particle size was 9 μm, and the amount of fine powder with a particle size of 4 μm or less was 1% of the whole.
A fine powder of 2% was obtained. Under the conditions of Example 3, it was tried to introduce compressed air of 0.882 MPa from the compressed gas supply nozzle 2, but a molten aggregate was generated and the experiment could not be continued.

Example 4 (according to claim 6) The same pulverized material 6 as in Example 1 was pulverized with a classifier and a flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air with a pressure of 0.686 MPa was introduced from the compressed gas supply nozzle 2 of the collision type air flow crusher, and
30 kg / H of the crushed material 6 from the crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

As the acceleration tube 3 and the collision member,
Although the same shape and size as those in Example 3 were used, Example 3
To the acceleration tube 3 that is indivisible structure, as in the present embodiment shown in FIG. 3, L ₁ from the throat portion 2a of the acceleration tube 3
Continuous operation was carried out for 12 hours using a material that could be divided at the position. As a result, a fine powder having a volume average particle diameter of 9 μm and a generation amount of fine powder of 4 μm or less was 12% of the whole was obtained.

Comparative Example 1 The same pulverized material 6 as in Example 1 was pulverized by the classifier and flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air with a pressure of 0.686 MPa was introduced from the compressed gas supply nozzle 2 of the collision type air flow crusher, and
20 kg / H of crushed material 6 from crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

The accelerating tube 3 is indicated by D in FIG.
= 9 mm, L = 25 D, θ = θ ₁ = θ ₂ = 7 °, and the collision member has a shape in which the jets from the accelerating tube 3 collide with each other while generating a drift and dispersed. using the collision member 4 _2, it was continuously operated for 12 hours. As a result, fine powder having a volume average particle diameter of 9 μm and a generation amount of fine powder having a particle diameter of 4 μm or less was 18% of the whole was obtained.

Further, under the conditions of Comparative Example 1, an attempt was made to introduce compressed air of 0.882 MPa from the compressed gas supply nozzle 2, but a molten aggregate was generated and the experiment could not be continued, and the supply amount was reduced. However, it was not effective in preventing the formation of melt aggregates.

Comparative Example 2 The same pulverized material 6 as in Example 1 was pulverized by the classifier and flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air with a pressure of 0.686 MPa was introduced from the compressed gas supply nozzle 2 of the collision type air flow crusher, and
17 kg / H of the crushed material 6 from the crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

The accelerating tube 3 is indicated by D in FIG.
= 9 mm, L = 25 D, θ = θ ₁ = θ ₂ = 7 °, and the collision member has a shape in which the jet from the accelerating tube 3 directly collides without causing uneven flow or dispersion. Figure 5
The collision member 41 shown in ₁ was used and continuously operated for 12 hours. As a result, the volume average particle diameter was 9 μm, and the particle diameter was 4
A fine powder having a generation amount of fine powder of less than μm of 14% of the whole was obtained.

Further, compressed air of 0.882 MPa was introduced from the compressed gas supply nozzle 2 under the conditions of Comparative Example 2, but melt agglomerates were generated, and the experiment could not be continued. Even if the supply amount was reduced, it was not effective in preventing the generation of molten aggregates.

Example 5 (according to claim 3) Styrene acrylic resin 100 parts by weight Phthalocyanine pigment 8 parts by weight Toner pigments having the above formulation are mixed in a mixer, and this mixture is extruded at about 200 ° C. After melt-kneading, the mixture was cooled and solidified, and the cooled product of the melt-kneaded mixture was roughly crushed into particles of 200 to 2000 μm with a hammer mill. This coarsely pulverized material was used as an object to be pulverized and pulverized by the pulverizer and flow shown in FIG. A fixed wall air classifier was used as a classifier for classifying the crushed powder into fine powder and coarse powder.

Compressed gas supply nozzle 2 of collision type air flow crusher
Compressed air having a pressure of 0.882 MPa is introduced from the pulverized material supply port 1 shown in FIG. 1 to the pulverized material 6 at 34 kg / Hr.
Supplied at the rate of The obtained pulverized product 10 was sent to the classifier 13, fine powder was removed as classified powder, and coarse powder was again charged into the accelerating pipe 3 as the pulverized product 6 together with the powder material from the pulverized product supply port 1.

The accelerating tube 3 is indicated by D in FIG.
= 9 mm, L = 25 D, θ = 7 °, θ ₁ = 12.8 °,
θ ₂ = 1 ° is used, and as the collision member, the collision member 4 ₂ shown in FIG. went. As a result, the volume average particle diameter was 9 μm, and the particle diameter was 4
A fine powder having a generation amount of fine particles of not more than μm of 16% of the whole was obtained.

Example 6 (according to claim 4) The same pulverized material 6 as in Example 5 was pulverized with a classifier and a flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air with a pressure of 0.686 MPa was introduced from the compressed gas supply nozzle 2 of the collision type air flow crusher, and
28 kg / H of the crushed material 6 from the crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

The accelerating tube 3 is designated as D in FIG.
= 9 mm, L = 18.5 D, θ = 5 °, θ ₁ = 8.9.
, Θ ₂ = 1 °, and the collision member 4 ₂ shown in FIG. 6 is used as the collision member, in which the jet flow from the accelerating tube 3 causes uneven flow and collides while being dispersed. Continuous operation was performed for an hour. As a result, the volume average particle diameter is 9 μm.
A fine powder having a particle size of 4 μm or less and 14% of the total amount of fine powder generated was obtained.

Example 7 (according to claim 5) The same pulverized material 6 as in Example 5 was pulverized with a classifier and a flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air having a pressure of 0.882 MPa was introduced from the compressed gas supply nozzle 2 of the collision type airflow crusher, and
30 kg / H of the crushed material 6 from the crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

The accelerating tube 3 is indicated by D in FIG.
= 9 mm, L = 18.5 D, θ = 3.5 °, θ ₁ = 6
And θ ₂ = 1 ° are used, and as the collision member, a collision member 4 ₁ shown in FIG. 5 having a shape in which the jet from the accelerating tube 3 directly collides without any uneven flow or dispersion is used. Then 1
Two hours of continuous operation was performed. As a result, the volume average particle size was 9 μm, and the amount of fine powder with a particle size of 4 μm or less was 1% of the whole.
A fine powder of 2% was obtained.

Example 8 (according to claim 6) The same pulverized material 6 as in Example 5 was pulverized by a classifier and a flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air having a pressure of 0.882 MPa was introduced from the compressed gas supply nozzle 2 of the collision type airflow crusher, and
34 kg / H of crushed material 6 from crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

As the acceleration tube 3 and the collision member,
Although the same shape and size as in Example 5 were used, Example 5
To the acceleration tube 3 that is indivisible structure, as in the present embodiment shown in FIG. 3, L ₁ from the throat portion 2a of the acceleration tube 3
Continuous operation was carried out for 12 hours using a material that could be divided at the position. As a result, fine powder having a volume average particle diameter of 9 μm and a generation amount of fine powder having a particle diameter of 4 μm or less was 16% of the whole was obtained.

Comparative Example 3 The same pulverized material 6 as in Example 5 was pulverized by the classifier and flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air having a pressure of 0.882 MPa was introduced from the compressed gas supply nozzle 2 of the collision type airflow crusher, and
20 kg / H of crushed material 6 from crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

The accelerating tube 3 is indicated by D in FIG.
= 9 mm, L = 25 D, θ = θ ₁ = θ ₂ = 7 °, and as a collision member, a jet flow from the accelerating tube 3 causes a non-uniform flow to collide while being dispersed. using the collision member 4 ₂ shown, was continuously operated for 12 hours. As a result, fine powder having a volume average particle diameter of 9 μm and a generation amount of fine powder having a particle diameter of 4 μm or less was 18% of the whole was obtained.

Comparative Example 4 The same pulverized material 6 as in Example 5 was pulverized by the classifier and flow shown in FIG. A fixed wall type air classifier was used as a classifier for classifying the pulverized powder into fine powder and coarse powder. Compressed air having a pressure of 0.882 MPa was introduced from the compressed gas supply nozzle 2 of the collision type airflow crusher, and
17 kg / H of the crushed material 6 from the crushed material supply port 1 shown in
It was supplied in the ratio of r. The crushed product 10 obtained is a classifier 13
, Fine powder is removed as classified powder, coarse powder again,
The pulverized material was supplied from the pulverized material supply port 1 into the acceleration tube 3 as the pulverized material 6 together with the powder raw material.

The accelerating tube 3 is indicated by D in FIG.
= 9 mm, L = 25 D, θ = θ ₁ = θ ₂ = 7 °, and the collision member has a shape in which the jet from the accelerating tube 3 directly collides without causing uneven flow or dispersion. Figure 5
The collision member 41 shown in ₁ was used and continuously operated for 12 hours. As a result, the volume average particle diameter was 9 μm, and the particle diameter was 4
A fine powder having a generation amount of fine powder of less than μm of 14% of the whole was obtained.

The crushing / classifying conditions and results of Examples 1 to 8 and Comparative Examples 1 to 4 are shown in the following [Table 1] and [Table 2], respectively.
Shown in

[0056]

[Table 1]

[0057]

[Table 2]

[0058]

As is apparent from the above description, claim 1
According to the collision type airflow pulverizer equipped with the decompression unit supply type pulverizing nozzle described in any one of 5 to 5, the high pressure gas is accelerated to supersonic velocity by the nozzle angle θ ₁ in the accelerating nozzle, and the velocity is increased by the nozzle angle θ _{2 in the} nozzle. Since the particles are collided and crushed in a state of being uniformly dispersed in the collision member in a state of being dispersed in the collision member, there is an effect that pulverization can be performed with high efficiency with little variation. According to the collision type airflow crusher of claims 1 to 5, when a high-pressure airflow of the same energy is used, the energy used for crushing can be effectively derived, and the crushing processing capacity is improved. Since generation of fine powder due to over-pulverization can be prevented, a pulverized product having a narrow particle size distribution can be obtained. Further, by appropriately changing and setting the pressure of the high-pressure gas, it becomes possible to carry out the grinding suitable for the property of the material to be ground, and it is possible to carry out the grinding with high yield and high productivity. According to the collision type airflow crusher described in claim 6, since the acceleration tube is configured by combining a plurality of annular bodies that can be disassembled and assembled, it is optimal according to the use and type of the crushed object. The shaped accelerating nozzle can be easily selected and configured. As described above, the crusher of the present invention can be very effectively applied to the production of fine powder products such as resins, agricultural chemicals, cosmetics, and pigments having a particle size of micron.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing a configuration example of a jet nozzle in a collision type airflow crusher of the present invention.

FIG. 2 is a schematic vertical cross-sectional view showing another configuration example of the ejection nozzle in the collision type airflow crusher of the present invention.

FIG. 3 is a schematic vertical cross-sectional view showing still another configuration example of the ejection nozzle in the collision type airflow crusher of the present invention.

FIG. 4 is a schematic explanatory view of a crushing device including a collision type airflow crusher and a classifier.

FIG. 5 is a schematic explanatory view showing an example of a collision member in the collision type airflow crusher of the present invention.

FIG. 6 is a schematic explanatory view showing another example of the collision member in the collision type airflow crusher of the present invention.

FIG. 7 is a schematic vertical cross-sectional view showing an example of the effective distance structure of the acceleration tube in the collision type airflow crusher of the present invention.

FIG. 8 is a schematic vertical cross-sectional view showing another example of the effective distance configuration of the acceleration tube in the collision type airflow crusher of the present invention.

[Explanation of symbols]

1 crushed object supply port 2 compressed gas supply nozzle 2a throat section 2b, 3a point 3 acceleration tube 3b effective outlet section 3c divergent outlet section 3d, 3e annular body 4, 4 ₁ , 4 ₂ collision member 5 discharge port 6 crushed object 7 Grinding chamber 8 Accelerator outlet 9 Collision surface 10 Crushed material 11, 12 Path 13 Classifier 14 High-speed airflow C Common centerline D Throat diameter L Effective length of acceleration tube θ Spread angle

Claims (6)

[Claims] 1. A crusher comprising a compressed gas supply nozzle, an acceleration pipe connected to the supply nozzle and having an object to be ground supply port, and a collision member for colliding and grinding the object to be ground, Regarding the pipe, the effective distance (effective length of the acceleration pipe) along the common center line of the supply nozzle and the acceleration pipe from the throat of the compressed gas supply nozzle to the effective outlet of the acceleration pipe is L, and
For the acceleration tube, the distance from the throat is 1 / the effective distance L
2, the distance along the common center line is L _1, and the inner peripheral surface of the accelerating tube has a double angle between the line connecting the throat and the effective outlet and the common center line (acceleration). The divergence angle of the tube is θ, and further, regarding the inner peripheral surface of the acceleration tube, the point on the inner peripheral surface of the acceleration tube whose distance from the throat along the common center line is L ₁ and the inner peripheral surface of the throat section The line connecting the points,
When θ ₁ is the angle formed by doubling the angle with the common center line, the collision type air flow crushing is characterized by having an accelerating tube that satisfies the relational expression shown in the following [Equation 1]. Machine. [Number 1] Ltan (θ / 2) ≧ L 1 tan (θ 1/2)
> (1/2) Ltan (θ / 2) 2. The acceleration tube has a diameter D of the throat portion, an effective length L of the acceleration tube, and a divergence angle θ of the acceleration tube, and a relational expression represented by the following [Formula 2] is satisfied, and , Θ is 1 ° to 7
The collision type airflow crusher according to claim 1, wherein the collision type airflow crusher has a gentle spread shape in which L is in the range of 8D to 30D at 0 °. [Expression 2] 1.8D ≧ Ltan (θ / 2) ≧ 0.13D 3. The crusher is provided with a collision member having a shape in which a jet flow from an accelerating tube causes uneven flow and collides while being dispersed, and uses a compressed gas having a pressure of 0.7 MPa or more. Is the relational expression shown in the following [Formula 3] between the diameter D of the throat, the effective length L of the acceleration tube, and the spread angle θ of the acceleration tube, and the angle θ is 2 ° to 7 °. so,
The collision-type airflow crusher according to claim 2, wherein L has a gentle spreading shape with a range of 10D to 30D. ## EQU00003 ## 1.8D ≧ Ltan (θ / 2) ≧ 0.19D 4. The crusher is provided with a collision member having a shape in which a jet flow from an accelerating tube causes a drift and collides while being dispersed, and uses a compressed gas having a pressure of 0.7 MPa or less. Is the relational expression shown in the following [Formula 4] between the diameter D of the throat, the effective length L of the acceleration tube, and the divergence angle θ of the acceleration tube, and the angle θ is 2 ° to 7 °. so,
The collision-type airflow crusher according to claim 2, wherein L has a gentle spread shape with a range of 8D to 25D. (4) 1.2D ≧ Ltan (θ / 2) ≧ 0.19D 5. The crusher is provided with a collision member having a shape in which a jet from the acceleration tube directly collides with neither uneven flow nor dispersion, and the acceleration tube has a throat diameter D and an effective acceleration tube. The relational expression shown by the following [Formula 5] is established between the length L and the divergence angle θ of the acceleration tube, and when the angle θ is 1 ° to 5 °, L
Is in the range of 8D to 30D, and has a gentle spreading shape, The collision type airflow crusher according to claim 2. [Expression 5] 0.78D ≧ Ltan (θ / 2) ≧ 0.13D 6. The accelerating tube is constituted by arranging a plurality of annular bodies side by side in the longitudinal direction of the accelerating tube and connecting them.
The collision type airflow crusher according to claim 1, 2, 3, 4, or 5, wherein the plurality of annular bodies are separable from each other.