JPH1043692A - Air current type classifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air current type classifier which can prevent coagulated substances from mixing with a powdery material to be introduced into a classification chamber. SOLUTION: A dispersion chamber 5a for dispersing a powdery material supplied with primary air and a classification chamber 4 which is installed continuously downward from the chamber 5a and classifies the powdery material introduced from the chamber 5a into fine powder and coarse powder are provided. A rotor 17 which forms a revolving current is installed in the chamber 5a, and a natural vortex or a semi-natural vortex is formed in the chamber 5a. In this way, coagulated substances in the chamber 5a are broken by shear force generated by the difference in circumferential speeds in the radial direction, the powdery material etc., after the breakage are separated centrifugally, and the particle size distribution of the powdery material introduced into the chamber 4 is adjusted within a given range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airflow classifier utilizing a swirling airflow for classifying fine particle powders such as electrophotographic toner into a predetermined particle size.

[0002]

2. Description of the Related Art Generally, an airflow classifier that uses a swirling airflow to classify fine particle powder such as an electrophotographic toner into a predetermined particle size is used. This airflow classifier 10
Reference numeral 0 denotes, for example, as shown in FIG. 1, a dispersion chamber 102 for dispersing a powder material (flow of the powder material and the like is indicated by an arrow) supplied together with primary air from an inflow port 101, and a dispersion chamber 102
And a classifying chamber 103 (for example, a dispersion separator manufactured by Nippon Pneumatic Co., Ltd.) which is provided continuously below and separates the powder material flowing from the dispersion chamber 102 into fine powder and coarse powder by centrifugal classification.

However, in such an airflow classifier 100, ultra-fine particles smaller than the target particle size interact with each other to form aggregates, or the dispersion chamber 1
In the pipes before reaching the inflow port 101 of No. 02, aggregates aggregated due to van der Waals force, liquid crosslinking, static electricity or the like are often introduced into the dispersion chamber 102. Such aggregates did not dissociate in their entirety even after entering the airflow classifier 100, and were thus separated as coarse powder in the classification chamber 103, making it difficult to remove them as fine powder. As a result, aggregates are mixed in the final product,
Obtaining a product with a high particle size distribution has not been easy.
In particular, when the powder material is an electrophotographic toner, it is necessary to remove even the product portion in order to remove it, and as a result, the product yield is reduced. If mixed into the final product, the aggregates are dissociated again into ultrafine particles therein, which has been a cause of deteriorating the quality in forming an image by electrophotography.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to prevent agglomerates from being mixed into a powder material flowing into a classification chamber. It is an object of the present invention to provide a pneumatic classifier that can perform the classification.

[0005]

According to the present invention, in order to solve the above-mentioned problems, a dispersion chamber for dispersing a powder material supplied together with carrier air, and a dispersion chamber provided continuously below the dispersion chamber. In an airflow classifier having a classifying chamber for centrifugally classifying the powder material flowing from the dispersion chamber into fine powder and coarse powder,
An airflow type classification device is provided, wherein a rotary rotor that forms a swirling flow is provided in the dispersion chamber. Further, according to the present invention, there is provided an airflow type classification device having the above configuration, further comprising a rotation speed control device for controlling the rotation speed of the rotary rotor. Further, according to the present invention, in the above configuration, the rotary rotor has a plurality of blades spaced apart around the circumference of the rotor, and the airflow classification in which the interval between adjacent blades is adjustable. An apparatus is provided. Further, according to the present invention, in the above configuration, there is provided an airflow type classification device in which the blades of the rotary rotor are replaceable with a plurality of types of blades having different outer edge shapes.

According to the present invention, in the above structure, the upright angle of the blades of the rotary rotor is 15 to 90.
An airflow classifier is provided which is set at a predetermined temperature. Further, according to the present invention, in the above configuration, the ratio of the diameter of the rotary rotor to the diameter of the dispersion chamber is 1.1 to 3.1.
An airflow classifier set to zero is provided. Further, according to the present invention, in the above configuration, there is provided an airflow classifier having an exhaust pipe for sucking the inside of the rotary rotor. Further, according to the present invention, in the above configuration,
An airflow classifier is provided, wherein the surface of the rotary rotor is formed at least with a wear-resistant surface.

Further, according to the present invention, there is provided an airflow classifier having the above-mentioned structure, wherein a release agent film is provided on a surface of the rotary rotor. Further, according to the present invention, there is provided an airflow classification device having the above-mentioned configuration, wherein the height of the rotary rotor is adjustable in the dispersion chamber. Further, according to the present invention, in the above configuration, there is provided an air flow type classification device in which the upper wall of the dispersion chamber is openable and closable, and the rotary rotor is supported by the upper wall of the dispersion chamber. Further, according to the present invention, there is provided an airflow type classification device having the above-described configuration, in which a supply port for supplying a powder material via carrier air faces the inside of the rotary rotor.

According to the present invention, in the above structure, the ratio of the axial length of the rotary rotor to the height of the dispersion chamber is such that when the height of the dispersion chamber is 1, An airflow classifier is provided in which the axial length of the rotor is set to be 0.10 to 0.9. Further, according to the present invention, in the above configuration, there is provided an airflow type classification device in which the rotary rotor is replaceable with a plurality of types of rotary rotors having different axial lengths. Further, according to the present invention, in the above configuration, the ratio of the dispersion chamber height to the axial length of the rotary rotor,
An airflow classifier is provided in which the height of the dispersion chamber is set to be 1.1 to 4.0 when the axial length of the rotary rotor is 1.

According to the present invention, in the above configuration, a partition wall for partitioning the dispersion chamber and the classification chamber is provided between the dispersion chamber and the classification chamber so as to be vertically adjustable. There is provided an airflow classifier which is adjustable with the partition wall. Further, according to the present invention, in the above configuration, a partition wall for partitioning the dispersion chamber and the classification chamber is provided between the dispersion chamber and the classification chamber, and an upper surface of the partition wall and the partition wall are provided. An airflow classifier is provided in which the inner surface of the upper wall of the dispersion chamber facing the upper surface of the wall is configured to perform centrifugal classification in cooperation. Further, according to the present invention, in the above configuration, the upper surface of the partition wall and the inner surface of the upper wall of the dispersion chamber facing the upper surface of the partition wall may have a vertical height of the dispersion chamber equal to the diameter of the dispersion chamber. An airflow classifier configured to narrow inward in the direction is provided.

According to the present invention, in the above configuration, the inner surface of the upper wall of the dispersion chamber is a horizontal surface,
An airflow type classification device is provided in which the upper surface of the partition wall is formed to be higher inward in the radial direction of the dispersion chamber. Further, according to the present invention, in the above configuration, the upper surface of the partition wall and the lower surface of the rotary rotor facing the upper surface of the partition wall are formed so as to perform centrifugal classification in cooperation. An airflow classifier is provided. Further, according to the present invention, in the above configuration, the upper surface of the partition wall and the lower surface of the rotary rotor facing the upper surface of the partition wall are arranged so that the vertical height of the dispersion chamber is set in the radial direction of the dispersion chamber. An airflow classifier configured to narrow inward is provided. Further, according to the present invention, in the above configuration, there is provided an airflow type classification device in which a lower surface of the rotary rotor and an upper surface of the partition wall facing the lower surface of the rotary rotor are arranged close to each other. Is done.

Further, according to the present invention, in the above structure, an air flow type classification device wherein a distance between a lower surface of the rotary rotor and an upper surface of the partition wall facing the lower surface of the rotary rotor is 7 mm or less. Is provided. Further, according to the present invention, in the above configuration, in a case where a fixing member is provided as a component of the rotary rotor in a lower portion of the rotary rotor, a lower surface of the fixing member is provided on a lower surface of the rotary rotor. An included air classifier is provided. Further, according to the present invention, in the above configuration, there is provided an airflow classification device in which the partition wall is replaceable with a plurality of types of partition walls having different top shapes. Further, according to the present invention, in the above configuration, there is provided an airflow type classification device in which a communication hole for communicating the dispersion chamber and the classification chamber is formed in the partition wall.

According to the present invention, in the above configuration, a communication hole communicating the dispersion chamber and the classifying chamber is formed in the partition wall, and the communication hole is formed around the entire periphery of the partition wall. , An airflow classifier configured as a plurality of slits is provided. According to the present invention,
In the above configuration, a communication hole communicating the dispersion chamber and the classification chamber is formed in the partition wall, and the communication hole is formed at a radially central portion of the partition wall to discharge fine powder in the classification chamber. An airflow classification device facing an outlet is provided. Further, according to the present invention, in the above configuration, there is provided an airflow type classification device in which a vane into which secondary air can flow is attached around a rotary rotor of the dispersion chamber. Further, according to the present invention, in the above configuration, it is possible to flow secondary air around the rotary rotor of the dispersion chamber, and the vane can be set at an arbitrary position in the height direction of the dispersion chamber. The present invention provides an airflow type classification device equipped with. Further, according to the present invention, there is provided an airflow classifier in the above configuration, wherein an inner surface of the dispersion chamber adjacent to an upper surface of the rotary rotor is covered with a gap seal.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. In FIG. 2, reference numeral 1 denotes a cylindrical main body casing. A cylindrical upper casing 2 is connected to an upper part of the main body casing 1, and a lower casing 3 is connected to a lower part of the main body casing 1. 3 communicate with each other in the up-down direction.

The upper casing 2 forms a dispersion chamber 2a. At the upper part of the upper casing 2, a supply tube 4 forming an inflow port is provided, and the powder material is introduced into the dispersion chamber 2 a from the supply tube 4 together with the carrier air (primary air). Descend while turning along. The dispersion chamber 2a has a center core 5 as a partition wall at its lower part. The center core 5 has a conical upper surface, and an annular gap 6 is formed between the outer peripheral edge of the center core 5 and the inner wall surface of the upper casing 2.

The main casing 1 mainly includes a classifying chamber 7.
Is composed. The classifying chamber 7 is defined by a center core 5 and a classifying plate 8 disposed below the center core 5. The classifying plate 8 forms an annular coarse powder discharge port 10 between the outer peripheral edge and the inner wall surface of the main casing 1, and a fine powder discharge port 11 is provided at the center of the classifying plate 8. Further, since the upper surface of the classifying plate 8 needs to keep equilibrium particles (limit particles) of the same diameter at any radial position in the classifying chamber 7 under a semi-free vortex, the height of the classifying chamber 7 is increased. It is formed in a substantially conical shape so as to be proportional to the radius of the classifying plate 8. The main body casing 1 also includes a guide vane 12.
have. The guide vane 12 is disposed between the center core 5 and the classifying plate 8 so as to surround the classifying plate 8, and air (secondary air flow) is introduced from outside through the guide vane 12. .

The lower casing 3 also serves as a coarse powder discharging hopper. For this reason, the above-mentioned coarse powder discharge port 10 is arranged facing the lower casing 3, and a hopper discharge port 13 is opened in the lower part of the lower casing 3. The lower casing 3 has a fine powder discharge chute 14 inside, and one end of the chute 14 is connected to the fine powder discharge port 11,
The other end extends outward from the side of the lower casing 3.

A suction fan (not shown) is connected to the other end of the chute 14 for discharging fine powder via a dust collector such as a cyclone. The suction force of the suction fan is necessary for the classification in the classifying chamber 7 by drawing powder material and the like from the annular gap 6 into the classifying chamber 7 and drawing external air from the guide vanes 12 into the classifying chamber 7. Generate a swirling flow. That is, due to the cooperative action of the inward swirling flow and the classifying plate 8, the velocity of the critical particles becomes equal to the inwardly flowing air velocity at the centrifugal sedimentation velocity at an arbitrary radial position in the classification chamber 7 at that point. . Therefore, particles larger than the limit particles have a large centrifugal force, move radially outward and are discharged from the coarse powder discharge port 10, and particles smaller than the limit particles have a larger drag due to the airflow, It moves inward in the radial direction and is discharged from the fine powder discharge port 11.

A rotor 17 is provided on the upper part of the dispersion chamber 2a. The rotor 17 includes a plurality of blades 17a arranged at equal intervals so as to form a cylindrical space, a support ring 17b for supporting the blades 17a, an upper wall 3b connected to the support ring 17b, and being connected to the dispersion chamber 2a. And a support shaft 17c extending upward through the support shaft 17c. Also,
A drive motor 24 is linked to the support shaft 17c via a pulley 22, a belt 23, and the like, and the rotation of the drive motor 24 rotates the rotor 17 to generate a swirling flow in the dispersion chamber 2a.

The rotation speed of the drive motor 24 is adjusted by a rotation speed control device 25, whereby the peripheral speed of the rotor 17 can be controlled to adjust the swirling flow in the dispersion chamber 2a. ing.

In the present embodiment, the peripheral speed of the rotor 17 is adjusted in the range of 10 to 130 m / s according to the classification target particle size. This value can be determined in consideration of the generation of a swirling flow (free vortex or semi-free vortex) that destroys agglomerates. However, if the peripheral speed is less than 10 m / s, the dissociation force is reduced due to the reduced swirling flow. If it is higher than 130 m / s, the swirling flow becomes rich, and the particles tend to decrease in dissociation force due to the control of the force toward the wall surface (outward in the radial direction).

The plurality of blades 17a of the rotor 17 are shown in FIG.
As shown in (1), it is attached to the ring 17b so that the distance between adjacent blades can be adjusted. This interval adjustment can be performed by appropriately changing the number of blades 17a mounted,
This is performed by changing the mounting position, and as a result, the angle θ1 about the support shaft 17c between the adjacent blades 17a, 17a is adjusted. In the present embodiment, the angle θ1
Is set in the range of 3 degrees to 45 degrees. The specific value of the adjustment angle θ1 can be determined in consideration of the generation of a swirling flow (free vortex or semi-free vortex) or the like that destroys aggregates, but when the angle θ1 is smaller than 3 degrees, the blades And the gap between the blades becomes too narrow, resulting in a decrease in the airflow swirlability. If the angle is larger than 45 degrees, the number of blades decreases, resulting in a decrease in the airflow swirlability.

The blade 17a of the rotor 17 has such a shape that its outer edge bulges laterally as it goes upward from its lower end. In the present embodiment, the outer edge of the blade 17a is
As shown in (1), the bulging portion has an angular shape. This shape can be determined in consideration of the generation of a swirling flow (free vortex or semi-free vortex) or the like that destroys the agglomerates. In addition, for example, as shown in FIG. The shape may be an arc shape.

In this embodiment, the ratio of the diameter d of the rotor 17 to the diameter D of the dispersion chamber 2a is d: D = 1:
It is desirable to be 1.1 to 3.0. This value is also determined in consideration of the generation of a swirling flow (free vortex or semi-free vortex) that destroys the aggregates, etc., and D / d is 1.1.
If the particle size is smaller, the suspension space of the particles is narrowed, and the turning ability is apt to be reduced. If the value is larger than 3.0, the particles cannot be provided with the necessary turning force, so that the capability is apt to be reduced.

Elements such as the blades 17a of the rotor 17 are made of a wear-resistant material. This is to suppress the abrasion of the rotor 17 even when the rotor 17 and the powder material collide, and to ensure the normal use of the rotor 17 for a long time. Of course, instead of using a wear-resistant material, an ordinary material may be provided with a wear-resistant coating.

In such an airflow classifier, when the powder material flows into the dispersion chamber 2a from the supply tube 4 together with the carrier air, the powder material is determined based on its own inertial force and the rotational force of the rotor 17. Is swirled in the dispersion chamber 2 a to perform centrifugal separation based on the swirling flow and centrifugal classification based on the swirling flow and the center core 5. The fine particles move toward the radially inner side of the dispersion chamber 2a, and the coarse particles move toward the inner peripheral surface side of the dispersion chamber 2a. As a result, the powder material having a certain particle size distribution is dispersed in the dispersion chamber 2a.
Gather on the inner circumference side of. In this case, van der Waals force,
Even if the aggregates agglomerated by liquid crosslinking, static electricity or the like flow into the dispersion chamber 2a, the swirling flow by the rotor 17 is generated by the dispersion chamber 2a.
In this case, the peripheral speed changes in the radial direction of the dispersion chamber 2a as a free vortex or a semi-free vortex, so that the shearing force based on the difference in the peripheral speed acts on the agglomerate, and the agglomerate becomes coarse powder. , Ultrafine particles and the like, and the particles produced thereby are subjected to the above-described centrifugation and the like.

The above-mentioned powder material having a constant particle size distribution is subsequently drawn into the classifying chamber 7 through the annular gap 6 by a suction force of a suction fan (not shown). A so-called dry centrifugal classification is performed by a swirling flow based on the air flowing through the guide vanes with the suction force of the fan. Due to this classification, the coarse particles move to the outer peripheral side of the classification chamber 7, enter the lower casing through the coarse powder discharge port 10, and are discharged from the hopper discharge port 13. It moves inward in the direction, enters the fine powder discharge chute 14 from the fine powder discharge port 11, and is discharged to the dust collector.

Therefore, in this air-flow classifier, the use of the rotor 17 in the dispersion chamber 2a can prevent agglomerates from being mixed into the powder material flowing into the classification chamber 7, and can prevent the powder from flowing into the classification chamber 7. The powder material (powder material having a certain particle size distribution) once centrifuged in the dispersion chamber 2a can be further centrifugally classified,
As a final product, a product having a highly accurate particle size distribution can be obtained.

FIG. 6 shows a second embodiment, FIG. 7 shows a third embodiment, FIG. 8 shows a fourth embodiment, FIG. 9 shows a fifth embodiment,
10 is a sixth embodiment, FIG. 11 is a seventh embodiment, FIGS. 12 to 15 are eighth embodiments, FIG. 16 is a ninth embodiment, FIG. 17 is a tenth embodiment, FIG. 19 shows the eleventh embodiment, and FIGS. 19 and 20 show the twelfth embodiment. In each of these embodiments, the same components as those in the above-described first embodiment will be described by assigning the same reference numerals.

In the second embodiment shown in FIG. 6, the upright angle θ2 of the blade 17a of the rotor 17 is in a predetermined angle range, specifically, in a range of 15 ° to 90 ° according to the classification target particle size. Is set to This is because, by adjusting the rising angle θ2 of the blade 17a, the pressure resistance of the rotor 17 is adjusted to increase or decrease the force applied to the powder material or the like, and the state of the swirling flow (natural vortex or semi-natural) in the dispersion chamber 2a. Vortex) and the like are intended to be accurate according to the classification target particle size.
If θ2 is smaller than 15 degrees, the swirl flow velocity decreases due to the blades, and if θ2 is larger than 90 degrees, the swirl flow velocity decreases because it opposes the rotation direction.

In the third embodiment shown in FIG. 7, one end of an exhaust pipe 15 is connected to the upper casing 2, and a blower (not shown) is connected to the other end of the exhaust pipe 15. The regulating valve 16 is located closer to the dispersion chamber 2a than the blower.
Is interposed. One end opening of the exhaust pipe 15 passes through the upper wall 2b of the dispersion chamber 2a and faces the inside of the rotor 17, whereby the rotor 17 is sucked by the blower. Note that this suction force is adjusted by the adjustment valve 16.

The rotor 1 is suctioned by the exhaust pipe 15.
A new centripetal force is generated toward 7, and the centripetal force and rotor 1
Due to the centrifugal force based on the rotation of 7, a strong dissociation action acts on the aggregate carried into the dispersion chamber 2 a in the vicinity of the rotor 17. As a result, the aggregates are destroyed, and a particle having a certain particle size distribution can be introduced into the classification chamber 7 through the annular gap 6 as in the above-described embodiment.

In the fourth embodiment shown in FIG. 8, the release agent coating 1 is formed on the outer surface of an element such as the blade 17a of the rotor 17.
8 are coated so that the rotor 1
7 can be prevented from adhering to the powder material, and normal use of the rotor 17 for a long time can be ensured.

In the fifth embodiment shown in FIG. 9, the height of the rotor 17 can be adjusted in the vertical direction in the dispersion chamber 2a, whereby the rotor 17 according to the characteristics of the powder material can be adjusted. Height can be set. The reason for adjusting the height of the rotor 17 is to prevent the powder from staying in the dispersion chamber and to adjust the free vortex region.

In the sixth embodiment shown in FIG.
The upper wall 2b of the dispersion chamber 2a can be opened and closed by a hinge 19, and the rotor 17 is supported on the movable upper wall 2b. Thus, by opening the upper wall 2b, the rotor 17 is exposed to the outside, so that cleaning, inspection, and disassembly of the rotor are facilitated.

In the seventh embodiment shown in FIG.
The supply tube 4 is connected to the upper wall 2b of the dispersion chamber 2a.
Of the rotor 1 penetrates through the upper wall 2b of the dispersion chamber 2a.
7 so that its rotor 17
The carrier air and the powder material can be supplied to the inside of the device. This is because the air in the rotor 17 is
When the rotor 17 is rotated to send radially outward as a swirling flow by rotating the rotor 17, the powder material collides with the blades 17 a of the rotor 17 to destroy aggregates. As a result, in addition to the shearing force based on the difference in the circumferential speed of the swirling flow in the radial direction, the above-mentioned collision force also contributes to the destruction of the aggregates, and the aggregates are contained in the powder material flowing into the classification chamber 7. Mixing can be more reliably prevented.

The eighth embodiment shown in FIGS.
14 shows a modification of the third embodiment. Therefore, in the eighth embodiment, in addition to the first embodiment, the same components as those in the third embodiment are denoted by the same reference numerals, and the description thereof is omitted. Also in this embodiment, the rotor 17 is disposed in the dispersion chamber 2a so as to extend downward from the inner surface of the upper wall 2b of the dispersion chamber 2a with the rotation axis directed vertically.
7 is to be sucked by an exhaust pipe 15.

The rotor 17 according to the eighth embodiment
Also, as shown in FIG. 13 and FIG.
7a are arranged at equal intervals, and the upper and lower end surfaces of each blade 17a are sandwiched and fixed by a pair of upper and lower support rings 17b. The internal space 17d of the rotor 17 and the dispersion chamber 2a are interposed between each adjacent blade 17a. And are to communicate. A pair of upper and lower support rings 17b of the rotor 17 has a support shaft 17c penetrating therethrough so as to be relatively non-rotatable. The support shaft 17b extends vertically so as to coincide with the axis of the dispersion chamber 2a. I have. This support shaft 17
c extends upward through the upper wall 2b of the dispersion chamber 2a, and a drive motor 24 is linked to the extended end of the dispersion chamber 2a via a pulley 22, a belt 23, etc., while the support shaft 17c
A fixing member (for example, a nut) 30 is attached (or screwed) to the lower end of the outer side of the lower support ring 17b so that the rotor 17 does not fall off. In this case, it is preferable to provide a stopper for restricting the upward movement of the rotor 17 between the upper wall 2b of the dispersion chamber 2a and the upper support ring 17b of the rotor 17 on the support shaft 17c.

On the lower surface of the lower support ring 17b,
As shown in FIG. 13, a cap 31 is detachably mounted. The cap 31 houses the fixing member 30 therein, and the cap 31 does not expose the fixing member 30 to the outside. The outer surface (lower surface) of the cap 31 is formed in a region below the cap 31 so that dry centrifugal classification can be performed under a semi-free vortex or the like in relation to the upper surface shape of the center core 5 described above. The vertical spacing between the center core 5 and the upper surface of the center core 5 is formed so as to become narrower toward the radially inward direction of the dispersion chamber 2a. The outer surface of the cap 31 has a conical shape. Accordingly, in the present embodiment, centrifugal classification is performed by the outer surface of the cap 31 and the upper surface of the center core 5 in the region below the cap 31 in the same manner as the centrifugal classification in the classification chamber 7 described above, and the diameter is smaller than that of the cap 31. In the region outside in the direction, the centrifugal classification is similarly performed by the inner surface of the horizontal upper wall 2b in the dispersion chamber 2a and the upper surface of the center core 5.

A plurality of types of rotors 17 having at least different lengths h in the axial direction (vertical lengths in FIGS. 12, 13 and 15) are prepared. They can be exchangeably arranged in the dispersion chamber 2a (see FIG. 12 and FIG. 15). The ratio of the axial length h of the rotor 17 to the height H of the dispersion chamber 2a is such that when the height H of the dispersion chamber 2a is 1, the axial length h of the rotor 17 is h. Is 0.
Preferably, it is set to be 10 to 0.9. The reason for this setting is that when the height H of the dispersion chamber is 1 and the axial length h of the rotor 17 is less than 0.10, the obtained swirling flow reaches the adjacent classification chamber 7. And the classification effect is apt to decrease, and the height H of the dispersion chamber 2a is reduced.
Is 1, the axial length h of the rotor 17 is 0.9.
Is exceeded, the rotor contacts the center core 5 and the rotation of the rotor cannot easily be continued.

Of course, the height H of the dispersion chamber 2a may be changed based on the axial length h of the rotor 17 by changing the viewpoint. That is, the predetermined rotor 17 may be fixedly arranged and the position of the center core 5 may be adjusted in the vertical direction. In this case, rotor 1
7, the ratio of the dispersion chamber height H to the axial length h is
The reciprocal of the ratio of the axial length h of the rotor 17 to the height H of the dispersion chamber, in other words, when the axial length h of the rotor 17 is 1, the dispersion chamber height H is 1.1 to It is preferable to set it to be 4.0. When the height of the dispersion chamber is less than 1.1 with respect to the axial length 1 of the rotor, the dispersion chamber is in contact with the center core 5 and the rotation of the rotor tends to be impossible to continue. On the other hand, when the height of the dispersion chamber exceeds 4.0, the obtained swirling flow is decelerated while reaching the adjacent classification chamber 7, and the dispersion effect tends to decrease.

Therefore, also in the eighth embodiment, as in the third embodiment described above, the shear force based on the difference in the peripheral speed in the radial direction is applied to the aggregate in the dispersion chamber 2a. Or the exhaust pipe 1 inside the rotor 17
5, the centrifugal force toward the center of the rotor 17 is generated, and the centrifugal force generated by the rotor 17 and the centrifugal force can act on the aggregates. Prevention of material aggregation can be enhanced.

The rotor 17 with respect to the dispersion chamber height H
By adjusting the ratio of the length h in the axial direction, even if a situation change such as a concentration change due to a change in the supply amount of the powder material occurs in the predetermined dispersion chamber 2a having a predetermined size, The vertical height of the swirl flow by the rotor 17 with respect to the destruction and separation of the object can be made appropriate, and the destruction and separation of the aggregates can be effectively and accurately generated in the dispersion chamber 2a by the swirl flow of the rotor 17. . Moreover, such a response can be promptly performed by replacing the rotor 17.

Of course, by adjusting the ratio of the height H of the dispersion chamber to the length h in the axial direction of the rotor 17 as well, the rotor 17 against the destruction and separation of agglomerates can be formed as in the above case.
The vertical height of the swirling flow can be adjusted properly, and the rotor 1
By the swirling flow of No. 7, destruction and separation of aggregates can be effectively and accurately generated in the dispersion chamber 2a. In this case, since the position adjustment of the center core 5 is performed, it is not necessary to prepare a plurality of types of rotors 17.

Further, in a region radially outward of the rotor 17, dry centrifugal classification is performed with a swirling flow such as a semi-free vortex by the inner surface of the dispersion chamber upper wall 2 b and the upper surface of the center core 5. Similarly, in the lower region, centrifugal classification is performed by the outer surface (lower surface) of the cap 31 of the rotor 17 and the upper surface of the center core 5, so that centrifugal classification is performed in the entire dispersion chamber 2a including the lower side of the rotor 17. As a result, it is possible to prevent the powder material from being reagglomerated (fluid state or the like) in the dispersion chamber 2a. In this case, the special shape is the conical upper surface of the center core 5 and the conical outer surface of the cap 31. With respect to the special shape, it is sufficient to perform machining or the like only on small items. A configuration for centrifugal classification can be obtained.

The ninth embodiment shown in FIG.
13 shows a modification of the embodiment. Therefore, in the ninth embodiment, in addition to the first embodiment, the same components as those in the eighth embodiment are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, the upper surface of the center core 5 is not a conical shape, but a frusto-conical shape in which the tip is cut off to have a flat surface. It is arranged so as to be close to the tip. Also in this case, the vertical gap between the distal end surface 5a of the center core 5 and the outer surface of the cap 31 becomes narrower inward in the radial direction, and, similarly to the eighth embodiment, a swirling flow such as a semi-free vortex. Performs centrifugal classification. In addition, since the distal end face 5a of the center core 5 is close to the cap 31, the formation of a stagnant space below the rotor 17 can be suppressed.

The tenth embodiment shown in FIG. 17 is a modification of the eighth embodiment. For this reason, in the tenth embodiment, in addition to the first embodiment, the same components as those in the eighth embodiment are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, the upper surface of the center core 5 is not conical, but a conical recess 32 is formed at the tip thereof, and the cap 31 enters the recess 32 from the tip. The center core 5 and the rotor 17 are arranged close to each other. Thereby, formation of a stagnation space below the rotor 17 can be further suppressed.

The eleventh embodiment shown in FIG. 18 is a modification of the ninth embodiment. Therefore, in the eleventh embodiment, in addition to the first embodiment, the same components as those in the ninth embodiment are denoted by the same reference numerals, and description thereof is omitted. In this embodiment, the cap 31 is not provided on the lower surface of the lower support ring 17b of the rotor 17, the thickness of the fixing member receiving portion 33 of the support ring 17b is increased toward the inside, and the fixing member 30 is The fixing member 30 can be deeply penetrated into the inside, so that even if the fixing member 30 is present, only a small part of the fixing member 30 protrudes downward. The lower surface is to be substantially flat. The tip surface 5a of the center core 5 having substantially the same area as the lower surface of the rotor 17 is arranged close to the lower surface of the rotor 17. Specifically, the close arrangement is such that the lower surface of the fixing member 30 and the center core 5 The tip surface 5a is set to be 7 mm or less. The reason why the diameter is set to 7 mm or less is that if the distance exceeds 7 mm, a stagnation portion (dead space) that is less likely to receive the swirling flow of the rotor is likely to accumulate dispersed powder. As a result, the lower surface of the flat rotor 17 and the flat front surface 5a of the center core are arranged close to each other, and the two surfaces 17 and 5a are opposed to each other with the same area. Is gone.

In the twelfth embodiment shown in FIGS. 19 and 20, a plurality of slits 34 are formed in the periphery of the center core 5 as communication holes. The plurality of slits 34 are arranged at equal intervals in the circumferential direction of the center core 5, and each slit 34 communicates the dispersion chamber 2 a and the classifying chamber 7. This slit 34
Is preferably 1 to 10 mm, more preferably 3 to 5 mm. If it is less than 1 mm, the separation of the dispersed powder becomes poor (not separated), and if it exceeds 10 mm, the dispersed powder jumps in (a substance having a size larger than the target particle size is mixed and re-agglomerated). Thereby, the inflow path area of the powder material flowing from the dispersion chamber 2 a into the classification chamber 7 is enlarged by the plurality of slits 34, and the separated powder material (coarse powder) is formed into an annular shape by the center core 5. The powder material does not pass through only the gap 6, and it is easy to prevent them from reaggregating. As a result, the powder material can be supplied to the classification chamber 7 in a desired particle size distribution state. Moreover,
The plurality of slits 34 reduce the velocity of the inflow air flowing into the classification chamber 7 from the dispersion chamber 2a, thereby preventing the centrifugal classification in the classification chamber 7 from being adversely affected.

In the twelfth embodiment, the description has been given of the prevention of the reagglomeration of the coarse powder moving from the dispersion chamber 2a to the classification chamber 7, but a communication hole is formed in the center of the conical center core 5 in the radial direction. The fine powder classified by centrifugation in the dispersion chamber 2a may be transferred from the communication hole to the classification chamber 7. Thereby, in addition to producing the same operation and effect as the eleventh embodiment, the fine powder classified by centrifugation in the dispersion chamber 2a can be discharged through the communication hole and the fine powder discharge port 11 in the classification chamber 2a. It is possible to prevent the dispersion chamber 2a from being adversely affected.

FIG. 21 shows the structure of the guide vane 12a mounted around the rotary rotor 17. The guide vanes 12a are fixed and arranged around the entire periphery of the rotary rotor, so that the angle can be adjusted. Air required for dispersion or classification is introduced through the guide vanes 12a while maintaining a uniform vortex motion. That is, the supplied particles are more accurately influenced by the centrifugal force and the speed of the airflow toward the center of the rotor, and are accelerated to the speed required for dispersion or classification.

FIG. 22 shows the structure of a guide vane 12a 'that can be set at an arbitrary position in the height direction of the dispersion chamber. When viewed from above, the guide vanes 12a 'are fixed and arranged around the entire periphery of the rotary rotor so that the angle can be adjusted. The air required for dispersion or classification undergoes uniform vortex movement through the guide vanes 12a ', and the air required for dispersion or classification is in a more appropriate state (position) in accordance with the true specific gravity or aggregation characteristics of the supplied particles. ). That is, the supplied particles are more accurately influenced by the centrifugal force and the speed of the airflow toward the center of the rotor, and are accelerated to the speed required for dispersion or classification.

FIG. 23 shows a ring cover 1 for covering the inner surface 2c of the dispersion chamber 2b adjacent to the upper surface 17F of the rotating rotor 17.
2 shows the structure of 7 g. The compressed air 17j is discharged to the labyrinth surface 17h by the ring cover 17g, so that particles rotating in the dispersion chamber 2b do not enter.

[0053]

Embodiments of the present invention will be described below. Example 1 A mixture of 85% by weight of a styrene acrylic copolymer, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded with an extruder, rolled, cooled and solidified, and then roughly ground with a hammer mill. did. Next, this coarsely pulverized product was subjected to a jet mill to obtain a weight average particle size of 7.0 [μ].
m] to obtain a finely pulverized product. Fig. 2
And the air-flow classifier shown in FIG. 3 to classify the fine powder under the condition of a rotating rotor peripheral speed of 60 m / s, and to obtain a weight average particle size of 7.
Number content of ultrafine particles of 3 [μm] or less than 4 [μm] 1
3.0% of the electrophotographic toner particles were obtained at 80.0% with respect to the charged amount of the pulverized material.

Example 2 Styrene acrylic copolymer 85
% By weight, 3% by weight of a charge control agent and carbon black 1
2% by weight of the mixture is melt-kneaded with an extruder,
After rolling, cooling and solidifying, the mixture was roughly pulverized with a hammer mill.
Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. This finely pulverized product is classified into fine powders by the airflow classifier shown in FIGS. 2 and 3 while changing the peripheral speed of the rotary rotor to 50 and 70 m / s. When the peripheral speed is 50 m / s, the weight average particle diameter is 7.35. [Μ
m], the number content of ultrafine particles of 4 [μm] or less 10.0
% Electrophotographic toner particles with respect to the pulverized material input amount of 7%.
9.0% recovered, and finely crushed electrophotographic toner particles having a number content of 16.0% of ultrafine particles having a weight average particle diameter of 7.25 [μm] and 4 [μm] or less at a peripheral speed of 70 m / s. 79.5% of the input amount was obtained.

Example 3 Styrene acrylic copolymer 85
% By weight, 3% by weight of a charge control agent and carbon black 1
2% by weight of the mixture is melt-kneaded with an extruder,
After rolling, cooling and solidifying, the mixture was roughly pulverized with a hammer mill.
Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. The finely pulverized material was subjected to the airflow classification device shown in FIGS.
Degree), classify the fine powder under the same conditions as in Example 1,
82.0% of the electrophotographic toner particles having a number content of 10.0% of ultrafine particles having a weight average particle diameter of 7.28 [μm] and 4 [μm] or less with respect to the charged amount of the pulverized material were obtained.

[Example 4] Styrene acrylic copolymer 8
A mixture of 5% by weight, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded by an extruder, rolled, cooled and solidified, and coarsely ground by a hammer mill. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. This finely pulverized material is subjected to the airflow classifier shown in FIGS.
The vertical ratio of the shape of the blade provided on the rotating rotor is 3:
The particles were classified into fine particles under the same conditions as in Example 3 to obtain electrophotographic toner particles having a weight-average particle size of 7.30 [μm] and a number content of ultrafine particles of not more than 4 [μm] of 9.0%. 82.0% was obtained based on the pulverized material input amount.

Example 5 Styrene acrylic copolymer 8
A mixture of 5% by weight, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded by an extruder, rolled, cooled and solidified, and coarsely ground by a hammer mill. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. This finely pulverized material is subjected to the airflow classifier shown in FIGS.
Fine particles were classified under the same conditions as in Example 4 with the mounting angle θ2 of the blades provided in the rotating rotor set to 70 degrees, and the number of ultrafine particles having a weight average particle diameter of 7.20 [μm] and 4 [μm] or less was included. The electrophotographic toner particles having a ratio of 8.0% were obtained at 82.0% with respect to the charged amount of the pulverized material.

Example 6 Styrene acrylic copolymer 85
% By weight, 3% by weight of a charge control agent and carbon black 1
2% by weight of the mixture is melt-kneaded with an extruder,
After rolling, cooling and solidifying, the mixture was roughly pulverized with a hammer mill.
Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. This finely pulverized material is rotated by a rotary rotor 1 with the airflow classifier shown in FIG.
7, and the outer diameter mounting ratio of the dispersion chamber 2a is set to 1: 1.5.
Fine powder was classified under the same conditions as in Example 1, and electrophotographic toner particles having a number content of ultrafine particles having a weight-average particle diameter of 7.30 [μm] and 4 [μm] of 11.0% were pulverized. 80.5%.

Example 7 Styrene acrylic copolymer 8
A mixture of 5% by weight, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded by an extruder, rolled, cooled and solidified, and coarsely ground by a hammer mill. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. The finely pulverized material is classified by the airflow classifier shown in FIG. 7 into fine particles at a flow ratio of the primary exhaust from the rotary rotor 17 to the fine powder exhaust port 15 of 4: 5, and at a low-course rotational peripheral speed of 70 m / s. 82.5% of electrophotographic toner particles having a number content of 8.0% of ultrafine particles having a weight average particle diameter of 7.25 [μm] or 4 [μm] or less with respect to the charged amount of the finely pulverized material were obtained.

Example 8 Styrene acrylic copolymer 7
A mixture of 5% by weight, 10% by weight of a magnetic powder, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded by an extruder, roll-solidified by cooling, and coarsely ground by a hammer mill. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. The finely pulverized material was coated with an alumina agent on the surface of the rotor blade 17a and classified into fine powder by the airflow classifier shown in FIG. 2, and the weight average particle diameter was 7.45 [μ].
m], the number content of ultrafine particles of 4 [μm] or less 9.0%
When the electrophotographic toner particles were operated continuously for 1000 hours and confirmed, 80.5% was stably obtained based on the charged amount of the finely pulverized material. After operation, there was no wear on the cabin. Other examples of the antiwear agent include carbide, ceramics, nitriding, and carburizing.

Example 9 Styrene acrylic copolymer 8
0% by weight, 5% by weight of carnauba wax and charge control agent 3
A mixture of 12% by weight of carbon black and 12% by weight of carbon black was melt-kneaded by an extruder, roll-solidified, solidified, and coarsely ground by a hammer mill. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.5 [μm] to obtain a finely pulverized product. The finely pulverized product is coated with a Teflon agent on the surface of the rotor blade 17a (see FIG. 8) by the airflow classifier shown in FIG. 2 and classified into fine powder, and the weight average particle size is 7.85 [μm], 4 [ When the electrophotographic toner particles having a number content of ultrafine particles of 12.0% or less having a number content of 12.0% or less were operated continuously for 1000 hours and confirmed, 85.5% was stably obtained with respect to the charged amount of finely pulverized material. After the operation, there was no powder adhesion inside the machine. Other examples of the release agent include a fluorine resin and a silicone resin.

Example 10 A mixture of 80% by weight of a styrene acrylic copolymer, 5% by weight of carnauba wax, 3% by weight of a charge control agent and 12% by weight of carbon black was melt-kneaded with an extruder, and then solidified by rolling and cooling. After that, the mixture was roughly pulverized with a hammer mill. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.5 [μm] to obtain a finely pulverized product. The finely pulverized material is classified by the air flow classifier shown in FIG. 2 into fine powder by lowering the setting position of the rotary rotor shown in FIG. 9 by 2/5 at the total height ratio of the dispersion chamber, and the weight average particle diameter is 7.80. Electrophotographic toner particles having a particle content of 13.0% [μm] and 4 [μm] or less were obtained stably at 86.5% with respect to the pulverized material input amount.

Example 11 A mixture of 80% by weight of a styrene acrylic copolymer, 5% by weight of carnauba wax, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded with an extruder, and roll-solidified by cooling. After that, the mixture was roughly pulverized with a hammer mill. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.5 [μm] to obtain a finely pulverized product. This finely pulverized product was finely classified by an airflow classifier shown in FIG. 11, and the weight average particle diameter was 7.8.
Number content of ultrafine particles of 0 [μm] or less than 4 [μm] 1
3.0% of electrophotographic toner particles were stably obtained at 85.5% with respect to the charged amount of the pulverized material.

Example 12 A mixture of 85% by weight of a styrene acrylic copolymer, 3% by weight of a charge control agent and 12% by weight of carbon black was melt-kneaded in an extruder, rolled, cooled and solidified, and then fed into a hammer mill. And coarsely pulverized. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. This finely pulverized product is subjected to the air-flow type classification device of the present invention shown in FIGS. 12 to 14 by using a rotary rotor having a peripheral speed of 60 m / s, an exhaust air volume passing through the rotor is 30% of the exhaust air volume of the entire classifier, and a diameter of the rotor 17 d was set to 0.8: 1 with respect to the ratio of the height H of the dispersion chamber to the ratio of the height H of the dispersion chamber under the condition of 1: 1.5 with respect to the diameter D of the dispersion chamber, and the powder was classified. 82.0% of electrophotographic toner particles having a number content of 16.0% of ultrafine particles having an average particle diameter of 7.2 [μm] or 4 [μm] or less with respect to the charged amount of the finely pulverized material were obtained.

Example 13 A mixture of 85% by weight of a styrene acrylic copolymer, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded in an extruder, rolled, cooled and solidified, and then subjected to a hammer mill. And coarsely pulverized. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. This finely pulverized product is subjected to the air-flow type classification device of the present invention shown in FIGS. 12 to 14 by using a rotary rotor having a peripheral speed of 60 m / s, an exhaust air volume passing through the rotor is 30% of the exhaust air volume of the entire classifier, and a diameter of the rotor 17 d is 1: 1.5 with respect to the dispersion chamber diameter D, and the axial length h of the rotor is 0.6: 1 with respect to the rotor diameter d.
Under the conditions described above, the height H of the dispersion chamber was set to 1.4: 1 with respect to the axial length h of the rotor 17 to classify fine powder, and the weight average particle diameter was 7.2 [μm] and 4 [μm]. The following electrophotographic toner particles having an ultrafine particle number content of 15.0% were obtained in an amount of 81.0% with respect to the pulverized amount.

Example 14 A mixture of 85% by weight of a styrene acrylic copolymer, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded with an extruder, rolled, cooled and solidified, and then fed to a hammer mill. And coarsely pulverized. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. This finely pulverized product was set in a conical shape as shown in FIG. 19 by the airflow classifier of the present invention, and the fine powder was classified under the same conditions as in Example 13; The electrophotographic toner particles having a number content of ultrafine particles of not more than 0.18 [μm] and 4 [μm] of 10.0% were obtained in an amount of 82.0% based on the amount of the finely pulverized material.

Example 15 A mixture of 85% by weight of a styrene acrylic copolymer, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded by an extruder, rolled, cooled and solidified, and then fed to a hammer mill. And coarsely pulverized. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. This finely pulverized product is placed at a position 90% of the diameter from the center of the center core 5 to the outside in the radial direction from the center of the center core 5 by the airflow classifier of the present invention shown in FIGS. A slit (diameter length 5 mm in width) was set as shown below, and then fine powder was classified under the same conditions as in Example 13 to obtain a weight average particle diameter of 7.
82.0% of electrophotographic toner particles having a number content of 8.0% of ultrafine particles having a particle size of 20 [μm] or 4 [μm] or less with respect to the charged amount of the finely pulverized material were obtained.

Example 16 A mixture of 85% by weight of a styrene acrylic copolymer, 3% by weight of a charge controlling agent and 12% by weight of carbon black was melt-kneaded in an extruder, rolled, cooled and solidified, and then fed into a hammer mill. And coarsely pulverized. Next, this coarsely pulverized product was finely pulverized with a jet mill to a weight average particle size of 7.0 [μm] to obtain a finely pulverized product. This finely pulverized product is fixed by providing the fixing member 30 so as to be buried in the support ring 17b of the rotor 17, as shown in FIG. With the distance between the lower surface of the member and the tip end surface of the center core 5 set to 5 mm, fine powder classification was performed under the same conditions as in Example 13 to obtain a weight average particle size of 7.25 [μm].
82.0% of electrophotographic toner particles having a number content of ultrafine particles of not more than 4 [μm] of 9.0% with respect to the charged amount of the finely pulverized material were obtained.

Example 17 Under the same conditions as in Example 7, half of the flow rate of the primary exhaust from the rotary rotor 17 via the fine powder exhaust port 15 was introduced from the vane 12a. As a result, 83.0% of electrophotographic toner particles having a number content of 8.0% of ultrafine particles having a weight average particle diameter of 7.25 [μm] or 4 [μm] or less with respect to the amount of finely pulverized material obtained were obtained. Was.

[Embodiment 18] Under the same conditions as in Embodiment 7, half the flow rate of the primary exhaust from the rotary rotor 17 through the fine powder exhaust port 15 was introduced from the vane 12a '. At this time, the inflow position of the vane 12a 'is set to the dispersion chamber H shown in FIG.
(2/3) H from the 2b plane as a starting point. as a result,
Electrophotographic toner particles having a number content of 8.0% of ultrafine particles having a weight average particle diameter of 7.25 [μm] or 4 [μm] or less were obtained at 83.5% with respect to the pulverized material input amount.

[Embodiment 19] Under the same conditions as in Embodiment 7, 1/10 of the flow rate of the primary exhaust from the outer peripheral portion 17g of the rotary rotor 17 through the fine powder exhaust port 15 is uniformly discharged from the outside into the dispersion chamber by compressed air. I did it. And 50
The operation was performed for 0 hour, and the confirmation was performed. The amount of electrophotographic toner particles having a number content of 8.0% of ultrafine particles having a weight average particle diameter of 7.25 [μm] or 4 [μm] or less was pulverized. 82.5%. At that time, the rotating rotor 17
And no particles were mixed in the area adjacent to the upper surface of the dispersion chamber.

[Comparative Example] Under the same classification conditions as in Example 1, under the condition that only a rotating rotor was not added, the coarsely pulverized product was finely pulverized with a jet mill to a weight average particle diameter of 7.0 [μm]. I got This finely pulverized product was finely classified using the airflow classifier shown in FIG. 1, and the weight average particle size was 7.5 [μ].
m], the number content of ultrafine particles of 4 [μm] or less 14.0
% Electrophotographic toner particles with respect to the pulverized material input amount of 7%.
5.0% was obtained.

Comparing the data obtained by the classifier having the rotating rotor in the example with the data obtained by the classifier of the comparative example not having the same, the classifier of the example improved the toner particle yield by 4 to 8%. You can see that it is. Since it is very difficult to increase the yield of toner particles by 1% in a conventional classifier, it has been confirmed that the mounting of a rotary rotor has a very remarkable effect on the improvement of toner particle yield in the examples. .

[0074]

According to the first aspect of the present invention, the swirling flow generated by the rotary rotor becomes a free vortex or a semi-free vortex in the dispersion chamber, and the peripheral velocity differs in the radial direction of the dispersion chamber. Even if the aggregate that has aggregated flows into the dispersion chamber, or even if the ultrafine particles aggregate in the dispersion chamber, a shear force based on the difference in peripheral speed acts on such aggregate. Thus, the aggregate can be separated into coarse powder, ultrafine particles and the like.

In such a powder material, the coarse powder is dispersed in the dispersion chamber at least based on a horizontal flow type (a type in which the horizontal flow type gravity sedimentation method is applied to the centrifugal separation method) in the dispersion chamber. Moving radially outward, the particles flow into the classification chamber, and other smaller particles, especially ultrafine particles, move to the radial center of the classification chamber. For this reason, it is possible to prevent agglomerates from being mixed into the powder material flowing into the classifying chamber, and in the classifying chamber, the powder material (powder material having a certain particle size distribution) once centrifuged in the dispersion chamber. ) Can be further classified by centrifugation.
As a result, a product having a high-precision particle size distribution can be obtained as a final product, so that the quality at the time of forming an image by electrophotography can be maintained. Also, the product yield is improved.

According to the second aspect of the present invention, the rotation speed of the rotor can be arbitrarily adjusted by the rotation speed control device, and the state of the swirling flow (natural vortex or semi-natural vortex) in the dispersion chamber can be adjusted to the classification target particle size. It can be tailored and accurate. For this reason, it is possible to enhance the destruction of the aggregates, the prevention of aggregation of the powder material in the dispersion chamber, and the centrifugal separation of the coarse powder and the fine powder in the dispersion chamber. According to the third aspect of the present invention, since the intervals of the plurality of blades of the rotor can be adjusted in the circumferential direction of the rotor, the state of the swirling flow (natural vortex or semi-natural vortex) in the dispersion chamber is classified. It is possible to obtain an accurate one corresponding to the particle size, and it is possible to obtain the same operation and effect as the above-described claim 2.

According to the fourth aspect of the present invention, as the blades of the rotary rotor, a plurality of types of blades having different outer edge shapes are appropriately selected and exchanged, so that the state of the swirling flow in the dispersion chamber (natural vortex or semi-natural vortex) is obtained. Vortex) can be made accurate according to the classification target particle size, and the same operation and effect as the above-described claim 2 can be obtained. According to the invention of claim 5, the outer diameter of the rotor is changed by adjusting the rising angle of the rotor blades to 15 to 90 degrees, and further, the pressure resistance of the rotor is changed by changing the outer diameter of the rotor. As a result, the change in angular velocity can be greatly changed. Thereby, the state of the swirling flow in the dispersion chamber and the adjustment width of the centrifugal force are increased, and the state of the swirling flow (natural vortex or semi-natural vortex) in the dispersion chamber is made closer to an accurate one according to the classification target particle size. Becomes easier.

According to the sixth aspect of the invention, by adjusting the ratio of the diameter of the rotor to the diameter of the dispersion chamber, the state of the swirling flow (natural vortex or semi-natural vortex) in the dispersion chamber can be adjusted to the target particle size for classification. According to the present invention, it is possible to obtain the same function and effect as the above-described claim 2. According to the invention of claim 7, by adjusting suction by the exhaust pipe to the inside of the rotor, a centripetal force toward the center of the rotor is generated, and by this centripetal force and centrifugal force by the rotor,
Breakage of aggregates and prevention of aggregation of the powder material in the dispersion chamber can be enhanced. According to the invention of claim 8, even if the powder material is a one-component powder containing a magnetic substance, it is possible to prevent abrasion due to the collision of the powder material with the rotor, and to improve the separation performance in the dispersion chamber for a long time. Can be maintained.

According to the ninth aspect of the present invention, even if the powder material is a low softening or low molecular weight resin, the powder material can be prevented from adhering to the rotor, and the separation performance in the dispersion chamber can be improved for a long time. Can be maintained over time. According to the tenth aspect of the present invention, since the height of the rotor can be adjusted, the rotor can be appropriately operated according to the characteristics of the powder material. According to the invention of claim 11,
Since the upper wall of the dispersion chamber is openable and closable, cleaning, inspection and disassembly of the inside of the rotor can be easily performed by opening the upper wall.

According to the twelfth aspect of the invention, when the air in the rotor is sent radially outward by the rotor as a swirling flow, most of the powder material collides with the rotor blades, and Will be destroyed. Therefore, in addition to the shearing force based on the difference in the circumferential speed of the swirling flow in the radial direction, the above-described collision force also contributes to the destruction of the aggregates, and the aggregates are contained in the powder material flowing into the classification chamber. Mixing can be more reliably prevented.

According to the thirteenth aspect, the vertical height of the swirling flow by the rotor for destruction and separation of agglomerates is appropriately set in the dispersion chamber, and the swirling flow of the rotor causes the swirling flow to disperse in the dispersion chamber. Aggregate destruction, separation, and the like can be effectively and accurately generated in the dispersion chamber. According to the fourteenth aspect, since the rotor can be replaced with a rotor having a different axial length, a situation change such as a change in concentration due to a change in the supply amount of the powder material occurs with respect to destruction and separation of aggregates. Even so, the best condition can be quickly achieved. According to the invention of claim 15, the height of the dispersion chamber with respect to the predetermined rotor is appropriately set with respect to the destruction and separation of the aggregates, and based on the height of the dispersion chamber, the rotor is swirled by the swirling flow. Aggregate destruction, separation, and the like can be effectively and accurately generated in the dispersion chamber.

According to the sixteenth aspect of the present invention, the height of the dispersion chamber can be adjusted by adjusting the position of the partition wall. Even if the situation changes, the best condition can be quickly achieved by adjusting the position of the partition wall.

According to the seventeenth aspect, since the upper surface of the partition wall and the inner surface of the upper wall of the dispersion chamber are formed so as to perform so-called dry centrifugal classification, the centrifugal classification can be performed even below the rotor. Is performed, and it is possible to prevent the powder material from being re-agglomerated (fluid state or the like). According to the eighteenth aspect of the present invention, dry centrifugal classification is performed with a semi-free vortex or the like between the upper surface of the partition wall and the inner surface of the upper wall of the dispersion chamber. Can be specifically obtained. According to the invention of claim 19, in order to perform dry centrifugal classification, it is only necessary to apply processing to a relatively small partition wall, and a configuration for centrifugal classification can be easily obtained.

According to the twentieth aspect, in addition to the case of the partition wall and the inner surface of the dispersion chamber upper wall, the upper surface of the partition wall and the lower surface of the rotor are formed so as to perform dry centrifugal classification. The centrifugal classification is also performed directly below the rotor below the rotor, so that the powder material can be more reliably prevented from reaggregating than in the case of the above-described claim 17. According to the twenty-first aspect of the present invention, dry centrifugal classification is performed with a semi-free vortex between the upper surface of the partition wall and the lower surface of the rotor. It can be obtained specifically. Claim 2
According to the second aspect, since the lower surface of the rotor and the upper surface of the partition wall facing the lower surface of the rotor are brought close to each other, the stagnation space below the rotor can be extremely reduced, and the powder material can be reduced. Reaggregation can be prevented.

According to the twenty-third aspect, when the distance between the lower surface of the rotor and the upper surface of the partition wall exceeds 7 mm,
When the distance between the lower surface of the rotor and the upper surface of the partition wall is 7 mm or less, the stagnation portion (dead space) that is less susceptible to the swirling flow of the rotor and dispersed powder accumulate.
The same operation and effect as the above-mentioned claim 24 can be specifically obtained. According to the invention of claim 24, even if a fixing member is provided at the lower part of the rotor, the same operation and effect as those of the above-mentioned claims 22 and 23 can be specifically obtained. Claim 2
According to the fifth aspect of the present invention, the partition wall can be used as a part, and the predetermined object of the above-described claims 16 to 19 can be quickly satisfied.

According to the twenty-sixth aspect, the area of the inflow path of the powder material flowing from the dispersion chamber into the classification chamber is enlarged by the communication hole, and the powder material passes only through the inflow path narrowed by the partition wall. It is possible to prevent the re-agglomeration of the produced powder material, and the powder material can be supplied to the classifying chamber in a desired particle size distribution state. In addition, the velocity of the air flowing into the classification chamber from the dispersion chamber is reduced, so that the centrifugal classification in the classification chamber is prevented from being adversely affected.

According to the twenty-seventh aspect, the second aspect is provided.
When obtaining the same operation and effect as 6, the coarse powder classified by centrifugation in the dispersion chamber is allowed to flow into the classification chamber as much as possible,
The spread of the particle size distribution of the powder material flowing into the classification chamber can be prevented as much as possible. According to the twenty-eighth aspect of the invention, in addition to producing the same effect as that of the twenty-sixth aspect, the fine powder classified by centrifugation in the dispersion chamber can be discharged through the communication hole and the fine powder discharge port in the classification chamber. In addition, it is possible to prevent stagnation in the dispersion chamber and adversely affect separation, classification, and the like.

According to the twenty-ninth aspect of the present invention, the classification accuracy is further improved by enhancing the dispersion or the classification force by the uniform swirling motion around the rotor. According to the invention of claim 30, classification accuracy is further improved by strengthening the dispersion or the classification force in the dispersion chamber according to the properties and characteristics of the particles. According to the thirty-first aspect of the present invention, continuous performance stability can be ensured by preventing particles from entering the rotor adjacent part.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of an airflow classifier according to the related art.

FIG. 2 is a conceptual diagram illustrating an airflow classifier according to the first embodiment.

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

FIG. 4 is an enlarged sectional view taken along line II-II of FIG.

FIG. 5 is a view showing a modified example of the outer edge shape of the rotor blade.

FIG. 6 is a conceptual diagram of a rotor according to a second embodiment.

FIG. 7 is a conceptual diagram illustrating an airflow classifier according to a third embodiment.

FIG. 8 is an explanatory diagram of a fourth embodiment.

FIG. 9 is a conceptual diagram illustrating an airflow classifier according to a fifth embodiment.

FIG. 10 is a conceptual diagram illustrating an airflow classifier according to a sixth embodiment.

FIG. 11 is a conceptual diagram showing an airflow classifier according to a seventh embodiment.

FIG. 12 is a conceptual diagram illustrating an airflow classifier according to an eighth embodiment.

FIG. 13 is an enlarged sectional view taken along the line AA of FIG.

FIG. 14 is an enlarged sectional view taken along line BB of FIG. 12;

FIG. 15 is a conceptual diagram showing a state where a different rotor is replaced in the eighth embodiment.

FIG. 16 is a conceptual diagram showing an airflow classification device according to a ninth embodiment.

FIG. 17 is a conceptual diagram showing a center core according to a tenth embodiment.

FIG. 18 is a conceptual diagram showing an airflow classification device according to an eleventh embodiment.

FIG. 19 is a conceptual diagram showing a center core according to a twelfth embodiment.

20 is a plan view of the center core shown in FIG.

FIG. 21 is a schematic view showing a dispersion chamber of Example 17.

FIG. 22 is a schematic view showing a dispersion chamber of Example 18.

FIG. 23 is a schematic view showing an adjacent surface of a rotor of Example 19.

[Explanation of symbols]

 2a Dispersion chamber 2b Upper wall 2c Inner surface 5 Center core 7 Classification chamber 8 Classification plate 12a Guide vane 12a 'Guide vane 15 Exhaust pipe 17 Rotor 17a Blade 17g Ring cover 17h Labyrinth surface 17j Compressed air 18 Coating 25 Rotation control device 30 Fixing member 31 Cap 34 Slit θ2 Blade rising angle d Rotor diameter D Dispersion chamber diameter H Dispersion chamber height h Rotor axial direction length

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Satoru Okano 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Kazuyuki Matsui 1-3-6 Nakamagome, Ota-ku, Tokyo Share Ricoh Company (72) Inventor Keiko Watanabe 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh Company

Claims (31)

[Claims] 1. A dispersion chamber for dispersing a powder material supplied together with carrier air, and a powder material continuously provided below the dispersion chamber and centrifuging the powder material flowing from the dispersion chamber into fine powder and coarse powder. An airflow classifier having a classification chamber for classifying, wherein a rotary rotor for forming a swirling flow is provided in the dispersion chamber. 2. The airflow classification device according to claim 1, further comprising a rotation speed control device for controlling a rotation speed of the rotary rotor. 3. The airflow classification device according to claim 1, wherein the rotary rotor has a plurality of blades spaced around the circumference of the rotor, and the interval between adjacent blades is adjustable. . 4. The blade of the rotary rotor is interchangeable with a plurality of types of blades having different outer edge shapes.
The airflow classifier according to any one of claims 1 to 3. 5. The airflow classification device according to claim 1, wherein the upright angles of the blades of the rotary rotor are set to 15 to 90 degrees. 6. The airflow classification device according to claim 1, wherein a ratio between a diameter of the rotary rotor and a diameter of the dispersion chamber is set to 1.1 to 3.0. 7. The airflow classification device according to claim 1, further comprising an exhaust pipe for sucking the inside of the rotary rotor. 8. The airflow classifier according to claim 1, wherein the surface of the rotary rotor is formed at least with a wear-resistant surface. 9. The airflow classification device according to claim 1, wherein a release agent film is provided on a surface of the rotary rotor. 10. The airflow classifier according to claim 1, wherein the height of the rotary rotor is adjustable in the dispersion chamber. 11. An upper wall of the dispersion chamber can be opened and closed,
The airflow classification device according to any one of claims 1 to 10, wherein the rotary rotor is supported by the upper wall of the dispersion chamber. 12. A supply port for supplying a powder material on carrier air in the rotary rotor.
12. The airflow classifier according to any one of claims 6 to 8 to 11. 13. The ratio of the axial length of the rotary rotor to the height of the dispersion chamber, where the axial length of the rotary rotor is 0, assuming that the height of the dispersion chamber is 1. 10
The airflow classification device according to claim 1 or 7, wherein the airflow classification device is set to 0.9. 14. The airflow classification device according to claim 13, wherein the rotary rotor is replaceable with a plurality of types of rotary rotors having different axial lengths. 15. The ratio of the height of the dispersion chamber to the length of the rotary rotor in the axial direction is 1.1 to 1.0 when the length of the rotary rotor in the axial direction is 1. 4.0
The airflow classifier according to claim 1, wherein the airflow classifier is set to be: 16. A partition wall for partitioning the dispersion chamber and the classification chamber is provided between the dispersion chamber and the classification chamber so as to be vertically adjustable, and can be adjusted by the partition wall. The airflow classification device according to claim 15, wherein 17. A partition wall for partitioning the dispersion chamber and the classification chamber is provided between the dispersion chamber and the classification chamber, and an upper surface of the partition wall and an upper surface of the partition wall facing the upper surface of the partition wall. The airflow classification device according to any one of claims 1, 7, 13 to 16, wherein the inner surface of the upper wall of the dispersion chamber is formed so as to perform centrifugal classification in cooperation. 18. An upper surface of the partition wall and an inner surface of an upper wall of the dispersion chamber facing the upper surface of the partition wall, the vertical height of the dispersion chamber being reduced toward a radially inward direction of the dispersion chamber. The air-flow classification device according to claim 17, which is formed as follows. 19. The dispersion chamber according to claim 17, wherein the upper surface of the upper wall of the dispersion chamber is a horizontal surface, and the upper surface of the partition wall is formed to be higher inward in the radial direction of the dispersion chamber. 2. An airflow classifier according to item 1. 20. The method according to claim 17, wherein an upper surface of the partition wall and a lower surface of the rotary rotor facing the upper surface of the partition wall cooperate to perform centrifugal classification. An airflow classifier according to any one of the preceding claims. 21. An upper surface of the partition wall and a lower surface of the rotary rotor facing the upper surface of the partition wall so as to reduce the vertical height of the dispersion chamber as it goes radially inward of the dispersion chamber. 21. The airflow classification device according to claim 20, wherein the airflow classification device is formed as follows. 22. The method according to claim 17, wherein the lower surface of the rotary rotor and the upper surface of the partition wall facing the lower surface of the rotary rotor are arranged close to each other. Airflow classifier. 23. The airflow classification device according to claim 22, wherein a distance between a lower surface of the rotary rotor and an upper surface of the partition wall facing the lower surface of the rotary rotor is 7 mm or less. 24. When a fixed member is provided as a component of the rotary rotor below the rotary rotor, the lower surface of the fixed member is included in the lower surface of the rotary rotor. 2. An airflow classifier according to item 1. 25. The airflow classification device according to claim 17, wherein the partition wall is replaceable with a plurality of types of partition walls having different top shapes. 26. A communication hole communicating with the dispersion chamber and the classification chamber is formed in the partition wall.
The airflow classifier according to any one of claims 5 to 10. 27. A communication hole communicating the dispersion chamber and the classifying chamber is formed in the partition wall, and the communication hole is formed as a plurality of slits around the entire periphery of the partition wall. The airflow classification device according to any one of claims 17 to 21. 28. A communication hole communicating with the dispersion chamber and the classification chamber is formed in the partition wall, and the communication hole is formed at a radially central portion of the partition wall, and fine powder in the classification chamber is formed. The airflow classification device according to any one of claims 17 to 21, which faces the discharge port. 29. The airflow classification device according to claim 1, wherein a vane into which secondary air can flow is mounted around the rotary rotor of the dispersion chamber. 30. A vane capable of inflow of secondary air and being set at an arbitrary position in the height direction of the dispersion chamber is mounted around the rotary rotor of the dispersion chamber. 30. The airflow classifier according to any one of items 29. 31. The airflow classification device according to claim 1, wherein an inner surface of the dispersion chamber adjacent to an upper surface of the rotary rotor is covered with a gap seal.