JPH0531391A - Impact-type air current pulverizer and pulverization of raw material to powder - Google Patents

Abstract

PURPOSE:To improve the efficiency of pulverization of an impact-type air current pulverizer used for the manufacture of color resin powder for toner. CONSTITUTION:The subject impact-type air current pulverizer is composed of a speed acceleration tube 3 for accelerating the speed of raw material for powder transported using a high pressure air, a pulyarization chamber 5 and an impact member 6 provided at an opposite position to the speed acceleration tube outlet in the pulverization chamber. In addition, supply apertures 1 for raw material for powder are provided in the speed acceleration tube, and a secondary air introduction aperture 11 for the speed acceleration tube is formed between the supply aperture for raw material for powder and the speed acceleration tube outlet. Further, the gradient angle (psi) of the secondary air introduction aperture with the center shaft of the speed acceleration tube satisfies 10 deg.<=psi<=80 deg., the gradient angle (rho) of the secondary air introduction aperture with a cross section which is vertical to the speed acceleration tube satisfies 10 deg.<=rho<=80 deg., and the tip of a collision surface of the impact member is allowed to assume a conical shape with a vertical angle of 110 deg. or larger to 180 deg. or smaller.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision type air flow pulverizer using a jet air flow (high pressure gas) and a method for pulverizing powder raw materials, and more particularly to toner or toner for use in an image forming method by electrophotography. The present invention relates to a collision type air flow pulverizer and a pulverizing method of powder raw materials for efficiently producing a colored resin powder.

[0002]

2. Description of the Related Art A collision type air flow crusher using a jet air flow conveys a powder raw material by a jet air flow, collides the powder raw material with a collision member, and pulverizes the powder by the impact force.

The details will be described below with reference to FIG.

Acceleration tube 1 connected to a compressed gas supply nozzle 2
3 is provided with a collision member 16 facing the outlet 14, and the flow of the high-pressure gas supplied to the accelerating pipe 13 causes the powder raw material supply port 1 communicated with the accelerating pipe 13 to enter the accelerating pipe 13. The body material 15 is sucked, jetted with high-pressure gas to collide with the collision surface of the collision member 16, and the impact is crushed. When the powder raw material 15 is used for pulverizing to a desired particle size,
A classifier is arranged between the powder raw material supply port 1 and the discharge port 9 to form a closed circuit, the powder raw material 15 is supplied to the classifier, and the coarse powder is supplied from the powder raw material supply port 1 for pulverization. The pulverized product is returned to the classifier from the discharge port 9 and classified again, and the fine powder becomes a fine pulverized product having a desired particle size.

However, in the above conventional example, the acceleration tube 1
Since it is difficult to sufficiently disperse the powder raw material 15 sucked and introduced into the high pressure gas stream 3, the acceleration pipe outlet 1
The powder flow ejected from No. 4 is separated into a flow having a high dust concentration and a light flow.

Therefore, the powder flow which hits the collision surface 17 facing each other becomes partial (local), and the efficiency is lowered,
Causes a decrease in processing capacity. In addition, if the treatment capacity is increased in such a state, the dust concentration is further increased locally, so that the efficiency is further reduced, and particularly in the case of the resin-containing material, a fused substance is generated on the collision surface 17, which is preferable. Absent.

Moreover, when the powder raw material 7 containing a large amount of coarse particles is introduced into the accelerating tube 13 by suction, the suction capacity of the powder raw material supply port 1 is lowered, and as a result, the processing capacity is lowered.

In order to improve the efficiency of crushing particles inside the accelerating tube 13, a crushing tube provided with a high-pressure gas feed tube for ejecting secondary high-pressure gas in front of the accelerating tube outlet 14 is disclosed in JP-B-4.
It is proposed in Japanese Patent Publication No. 6-22778. This is intended to promote the collision inside the acceleration tube 13, and is a useful means for a crusher that crushes only inside the acceleration tube 13, but it is made to collide with the collision member 16 to perform crushing. It is not a useful method in a collision-type airflow mill. because,
If the secondary high-pressure gas is introduced to accelerate the collision in the acceleration tube 13, the carrier gas flow due to the high-pressure gas introduced from the compressed gas supply nozzle 2 is obstructed, and the velocity of the powder flow ejected from the acceleration tube outlet 14 is increased. Will fall. Therefore, the impact force that collides with the collision member 16 decreases, and the pulverization efficiency decreases, which is not preferable.

On the other hand, as shown in FIGS. 9 and 10, the collision surface of the collision member in the conventional crusher is perpendicular or inclined (eg, to the axial direction of the accelerating tube) to the high-pressure air stream on which the powder material is placed. A flat surface having an angle of 45 ° has been used (see JP-A-57-50554 and JP-A-58-143853).

However, in the case of the collision surface 17 perpendicular to the axial direction of the acceleration tube 13 as shown in FIG. 9, the powder material 15 blown out from the acceleration tube outlet 14 collides with the pulverized material reflected on the collision surface 17. The coexistence ratio is high in the vicinity of the surface 17, and therefore the powder (powder raw material and pulverized material) in the vicinity of the collision surface 17
The concentration is high and the pulverization efficiency is not good.

Further, the primary collision on the collision surface 17 is the main component, and it cannot be said that the secondary collision with the crushing chamber inner wall 8 is effectively utilized. Furthermore, when crushing the thermoplastic resin, fusion and agglomerates are likely to occur due to local heat generation at the time of collision, which makes stable operation of the device difficult and causes a decrease in crushing ability. Therefore, it was difficult to increase the powder raw material concentration and use it.

Further, in the crusher of FIG. 10, since the collision surface 27 is inclined with respect to the axial direction of the acceleration tube 13, the powder concentration in the vicinity of the collision surface 27 is smaller than that of the crusher of FIG. However, the collision force due to the high pressure air flow is dispersed and decreases. Further, it cannot be said that the secondary collision with the crushing chamber inner wall 8 is effectively utilized. For example, as shown in FIG. 10, when the angle of the collision surface 27 is 45 ° with respect to the acceleration tube,
When crushing the thermoplastic resin, the above problems are few. However, since the impact force used for the crushing at the time of collision is small and the crushing due to the secondary collision with the crushing chamber inner wall 8 is small, the crushing capacity is 1 compared with the crusher of FIG.
The crushing ability drops to / 2 to 1 / 1.5.

Therefore, a crusher and a crushing method having good crushing efficiency have been desired.

On the other hand, the toner or the colored resin powder for toner used in the image forming method by electrophotography usually contains at least a binder resin and a colorant or magnetic powder. The toner develops the electrostatic image formed on the latent image carrier, and the formed toner image is transferred to a transfer material such as plain paper or a plastic film, and is heated and fixed, a pressure roller and a heating roller, or a heat and pressure roller. The toner image on the transfer material is fixed to the transfer material by a fixing device such as fixing means. Therefore, the binder resin used for the toner has a characteristic of being plastically deformed when heat and / or pressure is applied.

At present, a toner or a colored resin powder for a toner is melt-kneaded with a mixture containing at least a binder resin and a colorant or a magnetic powder (and optionally a third component), and the melt-kneaded product is cooled. Then, the cooled product is crushed and the crushed product is classified. Generally, the crushed product is roughly crushed (or medium crushed) by a mechanical impact crusher, and then the crushed coarse powder is finely crushed by a collision type air flow crusher using a jet stream. is there.

In such a case, in the conventional collision type air flow crusher and crushing method as shown in FIG. 9, if it is attempted to further improve the processing capacity, the powder raw material supply port 1 provided in the accelerating pipe 13 is insufficiently sucked. Occurs, or a fusion product is generated on the collision surface 17, and stable production cannot be performed. Therefore, in order to more efficiently generate the toner or the colored resin powder for the toner used in the image forming method by electrophotography, an efficient collision type airflow crusher and a crushing method that solve the above problems are desired. There is.

[0017]

SUMMARY OF THE INVENTION An object of the present invention is to provide an efficient collision type air flow crusher and a powder raw material crushing method in which the above problems are solved.

An object of the present invention is to provide a collision type air flow pulverizer for efficiently pulverizing powder mainly composed of a thermoplastic resin and a pulverizing method for powder raw material.

An object of the present invention is to provide a collision type air flow pulverizer for efficiently pulverizing a powder mainly composed of a thermoplastic resin and a method for pulverizing a powder raw material.

An object of the present invention is to provide a collision type airflow pulverizer and a powder raw material pulverizing method capable of efficiently producing toner or colored resin particles for toner used in a copying machine and a printer having a heating and pressing roller fixing means. To provide.

The object of the present invention is to obtain an average particle size of 20 to 2000.
An object of the present invention is to provide a collision type air flow pulverizer and a powder raw material pulverizing method capable of efficiently finely pulverizing resin particles having an average particle diameter of 3 to 15 μm.

An object of the present invention is to provide a collision type air flow pulverizer and a pulverizing method of powder raw material which efficiently pulverize by ejecting the powder from the outlet of the accelerating tube with good dispersion to prevent agglomerated powder in the accelerating tube. To do.

An object of the present invention is to provide a collision-type air flow which can effectively carry out a secondary collision in which the powder raw material injected from the outlet of the accelerating tube and colliding with the collision surface of the collision member further collides with the inner wall of the grinding chamber. An object of the present invention is to provide a pulverizer and a method for pulverizing powder raw materials.

[0024]

According to the present invention, an accelerating tube 3, a crushing chamber 5 for accelerating and conveying a powder material 15 by a high pressure gas, and a powder material 15 ejected from the accelerating tube 3.
In the collision type air flow pulverizer, which is provided with a collision member 6 for crushing by means of a collision force, the collision member 6 being provided in the crushing chamber 5 facing the acceleration tube outlet 4, The body raw material supply port 1 is provided, and the powder raw material supply port 1 and the acceleration pipe outlet 4 are provided.
And an acceleration pipe secondary air inlet 11 is provided between the secondary air inlet 11 and the secondary air inlet 11, and the inclination angle (ψ) of the secondary air inlet 11 with respect to the central axis of the acceleration pipe 3 satisfies 10 ° ≦ ψ ≦ 80 °. The inclination angle (ρ) of the air inlet 11 with respect to the cross section perpendicular to the central axis of the acceleration tube 3 satisfies 10 ° ≦ ρ ≦ 80 °, and the tip portion of the collision surface 7 of the collision member 6 has an apex angle 1
The present invention relates to a collision type airflow pulverizer having a cone shape of 10 ° or more and less than 180 °.

According to the present invention, the powder material 15 is conveyed and accelerated by the high pressure gas in the accelerating tube 3, the powder material 15 is jetted from the accelerating tube outlet 4 into the crushing chamber 5, and the powder material 15 is made to collide with the opposing collision member 6. In the crushing method of the crushed raw material to be crushed, the powder raw material 15 is introduced from a plurality of powder raw material supply ports 1 provided in the acceleration tube 3, and the powder raw material supply port 1 and the acceleration tube outlet 4 of the acceleration tube 3 are introduced.
Secondary air is introduced into the accelerating tube 3 from the accelerating tube secondary air introduction port 11 provided between the accelerating tube 3 and the accelerating tube 3 and the inclination angle (ψ) with respect to the central axis of the accelerating tube 3 is 10 ° ≦ ψ ≦ 80 degrees,
The inclination angle (ρ) with respect to the cross section perpendicular to the central axis of the acceleration tube 3 is 10 ° ≦ ρ ≦ 80 °, and the collision member 6 has a cone shape in which the tip portion of the collision surface 7 has an apex angle of 110 ° or more and less than 180 °. The powder raw material 15 is crushed by colliding with the powder raw material 15, and the pulverized material after the collision is further secondary collided with the crushing chamber inner wall 8 to pulverize the powder raw material 15.

According to the collision type air flow pulverizer and the method for pulverizing the powder raw material of the present invention, the powder which is the raw material to be powder can be efficiently pulverized to the order of several μm by utilizing the high-speed air flow.

In particular, the powder of the thermoplastic resin or the powder containing the thermoplastic resin as the main component can be efficiently pulverized to the order of several μm by utilizing the high-speed air stream.

The present invention will now be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic cross-sectional view of a collision type air flow crusher of the present invention and a flowchart of a crushing method in which a crushing process using the crusher and a classifying process by a classifier are combined. The powder raw material 15 to be crushed is supplied to the accelerating tube 3 through the powder raw material charging port 1 provided in the accelerating tube 3. A compressed gas such as compressed air is introduced into the accelerating tube 3 from the compressed gas supply nozzle 2, and the powder raw material 15 supplied to the accelerating tube 3 is instantaneously accelerated to have a high speed. The powder material 15 discharged into the crushing chamber 5 from the accelerating pipe outlet 4 at high speed collides with the collision surface 7 of the collision member 6 and is pulverized.

According to the present invention, as shown in FIG. 2 which is a sectional view taken along the line CC ′ of FIG. 1, a plurality of powder raw material charging ports 1 are provided for the acceleration tube 3, and a plurality of acceleration tube 3 are provided. A secondary air introduction port 11 is provided between the powder raw material charging port 1 and the acceleration pipe outlet 4, and the secondary air is introduced into the acceleration pipe 3 to disperse the powder in the acceleration pipe 3 and By more uniformly ejecting the powder from the outlet 4 and efficiently colliding with the opposing collision surface 7 of the collision member 6, the pulverization efficiency can be improved as compared with the conventional case.
The powder raw material 15 to be crushed is supplied to the accelerating pipe 3 by dispersing the powder raw material 15 from seven powder raw material supply ports 1 provided above the accelerating pipe 3 in FIG. Compressed gas such as compressed air is introduced into the accelerating tube 3 from the compressed gas supply nozzle 2, and the powder raw material 15 supplied to the accelerating tube 3 is supplied.
Is instantly accelerated and has a high velocity. The powder raw material 15 discharged into the crushing chamber 51 from the accelerating pipe outlet 4 at high speed collides with the collision surface 7 of the collision member 6 and is pulverized. Further, in such a crusher, a secondary air inlet 11 is provided between the powder raw material supply port 1 of the acceleration tube 3 and the acceleration tube outlet 4.
By introducing the secondary air into the acceleration tube 3, the suction capacity of the powder material supply port 1 is improved and the powder material 1 in the acceleration tube 3 is introduced.
By dispersing 5 and more uniformly ejecting the powder raw material 15 from the accelerating pipe outlet 4, and making it collide with the collision surface 7 of the opposing collision member 6 efficiently, pulverizability can be improved more than before. Here, the secondary air introduced contributes to deagglomerate and disperse the agglomeration of the powder raw material 15 that moves at high speed in the acceleration tube 3. In addition, there is an effect of accelerating the flow along the inner wall of the accelerating pipe, which is a portion where the accelerating gas flow velocity distribution is slow in the accelerating pipe 3.

This will be described in more detail by showing enlarged side views of the accelerating tube in FIGS. 5 and 6. As a result of extensive studies on the method of introducing the secondary air to be introduced, the following conclusion was reached.

That is, regarding the position of the introduction of the secondary air,
In FIG. 8, assuming that the distance between the powder raw material charging port 1 and the acceleration tube outlet 4 is x and the distance between the powder raw material charging port 1 and the secondary air inlet 11 is y, x and y are

[0032]

[Outside 3] Good results were obtained when

Regarding the introduction angle of the secondary air introduction port 11, when the angle with respect to the axial direction of the acceleration tube is ψ (FIG. 5), ψ is 10 ° ≦ ψ ≦ 80 °, more preferably 20 °.
When the condition of ≦ ψ ≦ 80 ° is satisfied and the angle with respect to the cross-sectional direction perpendicular to the central axis of the acceleration tube is ρ (FIG. 6),
ρ is 10 ° ≦ ρ ≦ 80 °, more preferably 20 ° ≦ ρ ≦
Good crushing results were obtained when the condition of 80 ° was satisfied.

Regarding the air volume of the secondary air to be introduced, the air volume of the carrier air flow by the high pressure gas introduced from the compressed gas supply nozzle 2 is aNm ³ / min, and the secondary air introduced from the secondary air inlet port. When the total air volume of bNm ³ / min is

[0035]

[Outside 4] Good results were obtained when pulverization was carried out under the conditions satisfying

The technical idea of the present invention is that a powder material is introduced into a carrier gas stream of high-pressure gas introduced from a compressed gas supply nozzle, jetted from an outlet of an accelerating tube, and collided with an opposing collision member surface to pulverize. It is based on the idea that the dispersion state of the powder in the acceleration tube may affect the pulverization efficiency in the collision type air flow pulverizer. That is, since the powder raw material supplied from the accelerating tube flows into the accelerating tube in an agglomerated state, the dispersion in the accelerating tube becomes insufficient, and when it is ejected from the accelerating tube outlet, the dust concentration varies and collides. It was thought that the member surface could not be used effectively and the crushing efficiency would decrease. This phenomenon becomes more remarkable as the crushing amount increases.

In order to solve this, the present inventors have devised the provision of a plurality of powder raw material charging ports and the introduction of secondary air. The present invention has been accomplished based on the idea that secondary air is introduced into an accelerating tube so as to disperse the powder raw material without disturbing the carrier flow of high-pressure gas. As the secondary air, either a highly compressed gas or a normal pressure gas may be used. It is very preferable to install an opening / closing device such as a valve at the secondary air inlet to control the amount of introduced air.

The number of inlets to be attached at which position in the circumferential direction of the accelerating tube may be appropriately set depending on the powder raw material, the target particle size and the like. As an example, FIG. 7 shows a case where eight secondary air inlets are attached in the circumferential direction of the acceleration tube.
7 is a sectional view taken along line BB ′ in FIG. In this case, the distribution of the secondary air from the eight locations may be appropriately set. Further, the cross section of the acceleration tube is not limited to the circular shape.

The inner diameter of the accelerating tube outlet 4 is usually 10 to 100.
It is preferable to have an inner diameter of mm and an inner diameter smaller than the diameter of the collision member 6.

The distance between the acceleration tube outlet 4 and the tip of the collision member 6 is preferably 0.3 to 3 times the diameter of the collision member 6. If it is less than 0.3 times, over-milling tends to occur, and 3
If it exceeds twice, the pulverization efficiency tends to decrease.

On the other hand, in the crusher of FIG. 1, since the collision surface 7 has a conical shape having an apex angle of 110 ° or more and less than 180 °, preferably around 160 °, the crushed pulverized material is substantially The particles are dispersed in the entire circumferential direction, cause a secondary collision with the crushing chamber inner wall 8, and are further crushed. FIG. 8 is a diagram schematically showing a cross section taken along the line AA ′ of the collision type airflow crusher shown in FIG. 1, and schematically showing a dispersed state of the pulverized material after the collision on the collision surface 7. ing. From FIG. 8, it is found that the air current type crusher of the present invention effectively utilizes the secondary collision of the crushed material on the crushing chamber inner wall 8. further,
In the crusher of the present invention, as shown in FIG. 1, the crushed material is well diffused in the radial direction of the collision member on the collision surface 7, so that the crushing chamber inner wall 8 is widely used for the secondary collision. Therefore, the concentration of the (crushed) material in the vicinity of the collision surface 7 does not become high, so that the processing efficiency of the crushing can be improved, and the fusion of the (crushed) material on the collision surface 7 can be effectively suppressed. It is possible.

The powder material 15 introduced into the crushing chamber 5 is crushed by the primary collision on the collision surface 7, and then further crushed by the secondary collision on the inner wall 8 of the crushing chamber. The crushed material is further crushed by the tertiary (and quaternary) collision with the crushing chamber inner wall 8 and the side surface of the collision member 6 before being conveyed to the discharge port 9. The pulverized product discharged from the discharge port 9 is classified into fine powder and coarse powder by a classifier such as a fixed wall airflow classifier. The classified fine powder is taken out as a crushed product. The classified coarse powder is fed into the powder raw material supply port 1 together with the powder raw material 15 which is newly fed.

As another example, FIG. 3 and FIG.
FIG. 2 is a cross-sectional view (cross section taken along the line CC ′ in FIG. 1) in which one and four powder raw material supply ports 1 are provided. Further, the cross section of the acceleration tube 3 is not limited to the circular shape.

The crushing chamber 5 of the collision type airflow crusher according to the present invention is not limited to the box type shown in FIG.

As described above, according to the apparatus and method of the present invention, the powder raw material is well dispersed in the accelerating tube, so that the powder collides efficiently with the collision surface of the collision member and the pulverization efficiency is improved. . That is, compared with the conventional crusher, the processing capacity is improved, and the particle size of the obtained product can be made smaller with the same processing capacity.

Further, in the conventional example, since the powder raw material collides with the collision surface of the collision member in a state where the powder raw material is agglomerated, a fusion material is easily generated especially when powder mainly containing a thermoplastic resin is used as the raw material. However, according to the present invention, since the colliding member collides with the colliding surface of the colliding member in a dispersed state, it is difficult to generate a fused substance.

Further, in the conventional example, since the powder raw material is agglomerated, there is a problem that over-pulverization is likely to occur, and the resulting pulverized product has a wide particle size distribution, but according to the present invention. It is possible to prevent excessive pulverization and obtain a pulverized product with a sharp particle size distribution.

Further, by efficiently introducing the secondary air, the air suction capacity at the powder raw material inlet is improved, so that the powder raw material conveying ability in the accelerating pipe is improved and the pulverization processing amount is improved. It can be higher than before. The effect of the apparatus and method of the present invention becomes more remarkable as the particle size becomes smaller.

Further, in the conventional example, the powder material injected from the accelerating tube outlet and colliding with the collision surface of the collision member has a high coexistence ratio with the powder material injected from the accelerating tube outlet and has a high powder concentration. However, according to the present invention, the tip of the collision surface of the collision member has an apex angle of 110 ° or more.
Since it has a cone shape of less than 80 °, the pulverized material after colliding with the collision surface is reflected to the inner wall side of the pulverization chamber, so that the powder concentration does not increase or is small, and the pulverization efficiency is improved.

Further, the crushed material after the collision with the collision surface effectively collides with the inner wall of the crushing chamber, so that the secondary collision is effectively performed, so that the pulverization efficiency is further improved.

[0051]

【Example】

Example 1 100 parts by weight of polyester resin (weight average molecular weight (M
w) = 50,000, Tg = 60 ° C. Phthalocyanine pigment 6 parts by weight Low molecular weight polyethylene 2 parts by weight Negative charge control agent 2 parts by weight (azo metal complex)

The above raw materials were mixed with a Henschel mixer to obtain a mixture. Next, this mixture is melt-kneaded at about 180 ° C. in an extruder, then cooled and solidified, and a cooled product of the melt-kneaded product is heated to 100 to 1000 μm with a hammer mill.
Coarsely crushed into m particles. This coarsely pulverized material was used as the powder raw material 7 and pulverized with the pulverizer and the flow shown in FIGS. 1, 2, 5, 6, 7 and 8. A fixed wall type air classifier was used as a classifying means for classifying the crushed powder into fine powder and coarse powder.

Here, in the collision type airflow crusher, the inner diameter of the outlet 4 of the acceleration tube 3 is 25 mm, and x = 80 mm, y = 45 mm, ψ = 45 °, ρ = 40 ° in FIGS. 5 and 6. Next air inlet 11 ... 8 conditions are satisfied in the circumferential direction, the collision member 6 is a columnar shape made of aluminum oxide ceramic having a diameter of 60 mm, and the tip of the collision surface 7 has an apex angle of 160 °. Had a conical shape with. The central axis of the acceleration tube 3 and the tip of the collision member 6 were aligned. The closest distance from the acceleration pipe outlet 4 to the collision surface 7 was 60 mm, and the closest distance between the collision member 6 and the crushing chamber inner wall 8 was 18 mm.

Flow rate 6.4 Nm ³ / min (pressure 6.0 kg / cm ² ) from the compressed gas supply nozzle of the collision type air flow crusher.
The compressed air was introduced to supply the powder raw material 15 from the powder raw material supply port 1 shown in FIG. 2 at a rate of 48 kg / hour. The pulverized powder raw material 15 was conveyed to a classifier, fine powder was removed as a classified powder, and coarse powder was again fed into the accelerating tube 3 together with the powder raw material 15 from the powder raw material supply port 1. As the secondary air, 0.1 Nm ^{3 /} min (5.0 kg / cm ² ) of compressed air was introduced from each of 8 locations A, B, C, D, E, F, G and H in FIG. 7.

[0055]

[Outside 5]

As a result, the fine powder has a volume average particle diameter of 7.5.
Milled powder (measured by Coulter Counter) was collected at a rate of 48 kg / hour. Further, no fusion deposit was generated even after continuous operation for 6 hours.

The particle size distribution of the toner can be measured by various methods, but in this embodiment, it was measured using a Coulter counter.

That is, a Coulter counter TA-II type (manufactured by Coulter) is used as a measuring device, and an interface (manufactured by Nikkaki) for outputting number distribution and volume distribution and a CX-1 personal computer (manufactured by Canon) are connected. , Electrolyte is 1st class sodium chloride
% NaCl aqueous solution is prepared. As a measuring method, a surfactant, preferably an alkylbenzene sulfonate, as a dispersant is added in an amount of 0.1 to 100 ml in the electrolytic aqueous solution of 100 to 150 ml.
Add ~ 5 ml, and then add 2 to 20 mg of the measurement sample. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment for about 1 to 3 minutes by an ultrasonic disperser, and a Coulter Counter TA-II type is used to form a 100 μm aperture as an aperture, and a particle number of 2 to 40 μm is used as a reference. The particle size distribution was measured and then the values according to this example were determined.

Example 2 The powder raw material used in Example 1 was prepared with the acceleration tube outlet 4 having an inner diameter of 2
5 mm, and x = 80 mm, y = 45 mm, ψ = 45 °, ρ = 45 ° in FIGS. 5 and 6, secondary air inlets ... Eight conditions are satisfied in the circumferential direction, and the collision member 6 is It was a columnar body made of aluminum oxide ceramics having a diameter of 60 mm, and the tip of the collision surface 7 had a conical shape with an apex angle of 120 °. The central axis of the acceleration tube 3 and the tip of the collision member 6 were aligned. The closest distance from the acceleration pipe outlet 4 to the collision surface 7 was 60 mm, and the closest distance between the collision member 6 and the crushing chamber inner wall 8 was 18 mm.

Compressed air of 6.4 Nm ³ / min (6 kgf / cm ² ) was introduced from the compressed gas supply nozzle of the collision type air flow crusher, and the secondary air was changed to A, B, C, D in FIG.
0.1 Nm ³ / min each from 8 locations of E, F, G and H
Compressed air of (5 kgf / cm ² ) was introduced, and the powder material 15 was supplied from the powder material supply port 1 shown in FIG. 3 at a rate of 40 kg / hour. The pulverized powder raw material 15 was conveyed to a classifier, fine powder was removed as a classified powder, and coarse powder was again fed into the accelerating tube 3 together with the powder raw material 15 from the powder raw material supply port 1.

As a result, the fine powder has a volume average particle diameter of 7.5.
A pulverized powder of μm (measured by Coulter counter) was collected at a rate of 40 kg / hour. Further, no fusion deposit was generated even after continuous operation for 6 hours.

Example 3 The powder raw material used in Example 1 was used, and the inner diameter of the accelerating tube outlet 4 was 2
5 mm, x = 80 mm, y = 45 mm, ψ = 45 °, ρ = 45 ° in FIGS. 5 and 6, secondary air inlets ... 8 conditions are satisfied in the circumferential direction, and the collision member 6 Was a columnar shape made of aluminum oxide ceramics having a diameter of 60 mm, and the tip of the collision surface 7 had a conical shape with an apex angle of 120 °. The central axis of the acceleration tube 3 and the tip of the collision member 6 were aligned. The closest distance from the acceleration pipe outlet 4 to the collision surface 7 was 60 mm, and the closest distance between the collision member 6 and the crushing chamber inner wall 8 was 18 mm.

Compressed air of 6.4 Nm ³ / min (6 kgf / cm ² ) was introduced from the compressed gas supply nozzle of the collision type air flow crusher, and the secondary air was A, B, C, D in FIG.
0.1 Nm ³ / min each from 8 locations of E, F, G and H
Compressed air (5 kgf / cm ² ) was introduced, and the powder material 15 was supplied from the powder material supply port 1 shown in FIG. 4 at a rate of 45 kg / hour. The pulverized powder raw material 15 was conveyed to a classifier, fine powder was removed as a classified powder, and coarse powder was again fed into the accelerating tube 3 together with the powder raw material 15 from the powder raw material supply port 1.

As a result, the fine powder has a volume average particle diameter of 7.5.
Pulverized powder of μm (measured by Coulter counter) was collected at a rate of 45 kg / hour. Further, no fusion deposit was generated even after continuous operation for 6 hours.

Comparative Example 1 The pulverized raw material used in Example 1 was pulverized by a conventional collision type pulverizer shown in FIG. In the crusher, the collision surface 17 at the tip of the collision member 6 is a plane perpendicular to the axial direction of the acceleration tube 12, and the inner diameter of the acceleration tube outlet 14 is 25 mm. The accelerating tube 12 is connected to the compressed gas supply nozzles 2 to 7.2.
Compressed gas of Nm ³ / min (6 kgf / cm ² ) was supplied, and fine powder (crushed product) was crushed by setting a classifier so that the weight average particle diameter was 7.5 μm. The crushed material that collided with the collision surface 17 is reflected in the direction opposite to the discharge direction from the accelerating tube, so that the existing concentrations of the pulverized material and the powder raw material in the vicinity of the collision surface are remarkably high. Therefore, if the supply rate of the powder raw material exceeds 4.5 kg / hour, fusion and agglomerates may start to occur on the collision surface 17 of the collision member 16, and the fusion may clog the crushing chamber or the classifier. It was Therefore, it was forced to reduce the crushing amount to 15 kg per hour, which became the limit of the crushing capacity.

When fine powder (crushed product) having a weight average particle diameter of 11 μm is obtained, if the feed rate of the powder raw material exceeds 9 kg / hour, the collision surface 17 of the collision member 16 will be affected. At this point, fusion and agglomerates began to occur, which became the limit of the crushing ability.

Comparative Example 2 The powder raw material used in Example 1 was pulverized in the same manner as Comparative Example 1 using the collision type air flow pulverizer shown in FIG. The crusher is the same as the crusher used in Comparative Example 1 except that the collision surface 27 at the tip of the collision member 6 is a plane having an inclination of 45 ° with respect to the axial direction of the acceleration tube 12. Is.

The crushed material that collided with the collision surface was reflected in a direction away from the acceleration tube outlet 14 as compared with Comparative Example 1, so that fusion and agglomeration did not occur on the collision surface 27 of the collision member 26. However, since the impact force becomes weak upon collision, the pulverization efficiency was poor, and only about 15 kg of fine powder (pulverized product) having a weight average particle diameter of 7.5 μm was obtained per hour.

Further, when obtaining fine powder (crushed product) having a weight average particle diameter of 11 μm, only about 9 kg per hour was obtained.

Table 1 shows the results of Examples 1 to 3 and Comparative Examples 1 and 2 obtained as described above.

[0071]

[Table 1]

[0072]

As described above, according to the collision type air flow pulverizer and the method for pulverizing the powder raw material according to the present invention, the acceleration tube, the pulverizing chamber and the accelerating tube for accelerating the transportation of the powder raw material by the high pressure gas. In a crusher equipped with a collision member for crushing the powder material ejected more by collision force, the powder material is dispersed and supplied into the acceleration tube by providing a plurality of powder material supply ports in the acceleration tube. In addition, the secondary air is introduced in a spiral shape to enhance the suction ability of the powder raw material, and the powder material is ejected from the acceleration tube with good dispersion, and the crushed object efficiently collides with the collision surface of the collision member, so that the pulverization efficiency is improved. .

Furthermore, by making the shape of the collision surface of the collision member a specific cone shape, it is possible to prevent fusion and agglomerates from being generated when the object to be crushed is crushed, and to enable stable operation of the apparatus. In addition, since the crushed material strongly collides against the inner wall of the crushing chamber, the conventional crushing ability can be significantly improved.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a collision type crusher of the present invention and an example of a flowchart of a method for pulverizing a powder raw material in which the pulverizer and a classifier are combined.

FIG. 2 shows a specific example of a powder raw material supply port, and FIGS.
FIG. 9 is a sectional view taken along line CC ′ of FIG.

FIG. 3 is a view showing a specific example of a powder raw material supply port, and FIGS.
FIG. 9 is a sectional view taken along line CC ′ of FIG.

FIG. 4 is a view showing a specific example of a powder raw material supply port.
FIG. 9 is a sectional view taken along line CC ′ of FIG.

5 is a cross-sectional view taken along the line AA ′ of FIG. 1 showing the crushing chamber.

FIG. 6 is a cross-sectional view showing an acceleration tube of the collision type crusher of the present invention.

FIG. 7 is a cross-sectional view showing an acceleration tube of the collision type crusher of the present invention.

FIG. 8 is a BB ′ of FIGS. 5 and 6 showing a secondary air supply port.
FIG.

FIG. 9 is a diagram showing a schematic cross-sectional view of a collision type crusher of a conventional example and a flowchart of a crushing method.

FIG. 10 is a diagram showing a schematic sectional view of a collision type crusher of a conventional example and a flowchart of a crushing method.

[Explanation of symbols]

1 Powder raw material supply port 2 Compressed gas supply nozzle 3 Accelerator 4 Accelerator outlet 5 crushing room 6 collision member 7 collision surface 8 crushing room wall 9 outlet 11 Secondary air supply port 13 Accelerator 14 Accelerator outlet 15 Powder raw material 16 Collision member 17 Collision surface 26 Collision member 27 Collision surface

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuhide Goseki             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation

Claims (4)

[Claims] 1. A collision member for crushing the powder raw material ejected from the accelerating pipe by a collision force, the accelerating tube for accelerating the powder raw material by high-pressure gas, and the crushing member. In a collision type air flow crusher provided in the crushing chamber facing the acceleration pipe outlet, the acceleration pipe is provided with a plurality of powder raw material supply ports, and the acceleration pipe two is provided between the powder raw material supply port and the acceleration pipe outlet. A secondary air introduction port is provided, and an inclination angle (ψ) of the secondary air introduction port with respect to the central axis of the acceleration pipe satisfies 10 ° ≦ ψ ≦ 80 °, and the secondary air introduction port has a central axis of the acceleration pipe. The inclination angle (ρ) with respect to the vertical cross section satisfies 10 ° ≦ ρ ≦ 80 °, and the tip portion of the collision surface of the collision member has an apex angle of 110.
A collision-type airflow crusher characterized by having a cone shape of not less than 180 ° and less than 180 °. 2. The distance between the powder raw material supply port provided in the acceleration pipe and the acceleration pipe outlet is x, and the distance between the powder raw material supply port and the acceleration pipe secondary air introduction port provided in the acceleration pipe is y. If
x and y are The collision type airflow crusher according to claim 1, wherein 3. A method for pulverizing a pulverizing raw material, which comprises accelerating a powder raw material by high-pressure gas in an accelerating tube, jetting the powder raw material from an accelerating tube outlet into a pulverizing chamber, and crushing the powder raw material by colliding with an opposing collision member. The powder raw material is introduced from a plurality of powder raw material supply ports provided in the acceleration tube, and the acceleration is performed from an acceleration tube secondary air introduction port provided between the powder raw material supply port of the acceleration tube and the acceleration tube outlet. Secondary air is introduced into the tube, and the direction of introduction is such that the inclination angle (ψ) with respect to the central axis of the acceleration tube is 10 ° ≦ ψ ≦ 80 °, and the inclination angle (ρ) with respect to the cross section perpendicular to the central axis of the acceleration tube.
Is 10 ° ≦ ρ ≦ 80 °, and the powder raw material is crushed by colliding the powder raw material with a collision member having a cone shape with the tip portion of the collision surface having an apex angle of 110 ° or more and less than 180 °, and the pulverized product after the collision is further A method of pulverizing a powder raw material, which comprises crushing the powder raw material by secondary collision with a crushing chamber wall. 4. If air amount ANM ³ / min of high pressure gas for transporting accelerate grinding object that is introduced into the acceleration tube, the air volume of the secondary air introduced into the acceleration tube was BNM ³ / min,
a and b are [outside 2] 4. Grinding under conditions satisfying
A method for pulverizing the powder raw material as described.