JP4911991B2 - Airflow classifier, vibration device - Google Patents

Description

  The present invention relates to a classification apparatus and classification method for electrophotographic powders such as containers or hoppers or filter-type filtration devices or collection containers or feeders suitable for adhering and removing powders such as electrophotographic powders and toners for electrophotography. In particular, the present invention relates to a classification device and a classification method suitable for classification of a small particle size toner for low-temperature fixing.

In recent years, the demand for powders or fine particle powders has increased, and various containers and apparatuses have been used to handle these powders. For example, in image forming methods such as electrophotography and electrostatic photography, toner is used to develop an electrostatic latent image. In order to obtain the final product by crushing and classifying the solid particles in the production of electrostatic latent image toner, which requires the final product to be fine particles, a binder resin, a colorant (dye, pigment, magnetic) A predetermined material such as a body is melt-kneaded, cooled and solidified, and then pulverized and classified.
In recent years, based on customer demand for high-speed printing and high image quality in electrophotography, the specific surface area of toner has increased due to low melting point for high-speed printing and small particle size for high image quality.
Furthermore, in order to cope with high definition of the system, high Wax filling into the toner is required.

For example, in order to classify a fine particle powder such as an electrophotographic toner, a classifier using a swirling airflow is generally used. For example, a dispersion separator (DS type: manufactured by Nippon Pneumatic Co., Ltd.) as shown in FIG. ) Is used. Also, in the production of such toner, a container or hopper for primary storage of powder, or a filter type filtration device or collection container or powder for solid-gas separation of toner during transport, pulverization and classification A feeder is used to quantitatively supply the material, but the increase in specific surface area associated with atomization or a decrease in fluidity occurs to meet the quality requirements of the powder, resulting in agglomeration and adhesion on the inner wall surface, and deposition collapse There is a problem in quantitative discharge to repeat the process. Also, with conventional DS classifiers, when the classified coarse particles are discharged, they aggregate and adhere to the inner wall surface of the hopper, and do not discharge quantitatively due to repeated collapse of the sediment, and in the worst case, impede the next process It has become.
In particular, when precise classification is required, closed-class classification, in which the classifiers are combined in two stages in series and connected between them by a conveyance path, is the mainstream, so the amount of powder circulation in the machine due to pulsation is disturbed and classification accuracy decreases. Or, in the worst case, powder clogging occurs in the machine, and a state where classification cannot be continued occurs.

In recent years, the same phenomenon occurs in the classification stage even in a toner manufactured by a chemical reaction without being pulverized as a polymerized toner.
As an invention aiming at preventing adhesion in the machine by processing on the adhesion surface of the classifier, those using a fluororesin at the classification edge are disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 02-294660) and Patent Document 2 ( Japanese Patent Laid-Open No. 02-294661), Patent Document 3 (Japanese Patent Laid-Open No. 02-294661), and Patent Document 4 (Japanese Patent Laid-Open No. 02-294663) are not sufficient during continuous classification.

  There are Patent Document 5 (Japanese Patent Laid-Open No. 2004-113939) and Patent Document 6 (Japanese Patent Laid-Open No. 2003-280263) as those using a conductive fluororesin on the wall surface of the fluidized bed grinder. That's not true.

  A method for preventing adhesion using a vibration hopper is also proposed in Patent Document 7 (Japanese Utility Model Publication No. 61-037674), but the classification accuracy is lowered because the main body vibrates.

Japanese Patent Laid-Open No. 02-294660 JP 02-294661 A Japanese Patent Laid-Open No. 02-294661 Japanese Patent Laid-Open No. 02-294663 JP 2004-1113839 A JP 2003-280263 A Japanese Utility Model Publication No. 61-037674

An object of the present invention is to suppress adhesion and aggregation in a hopper, a filter-type filtration device, a collection container, or a feeder, and to perform smooth powder filtration, collection, or supply. In addition, in the pulverization of producing a toner that provides a stable charge amount and good image quality with a toner for developing electrostatic images, it suppresses adhesion / aggregation, reduces the incidence of ultrafine powder and coarse particles, and is economical in terms of production efficiency. It is to provide an advantageous manufacturing method.
Further, the object of the present invention with respect to the above-mentioned problems of the prior art is to facilitate discharge of coarse particles and fine particle hopper inner wall surface and container inner wall surface, and smoothly discharge coarse particles and fine particles to the next process by pulsating flow. The purpose is to propose a new classification method.

The said subject is solved by following (1)-( 12 ) of this invention.
(1): A classification device including classification means and a powder container for temporarily storing powder under the classification means , wherein the powder container includes a hopper-shaped vibrating portion that vibrates due to vibration of the classification means. The vibrating part has a scissors sandwiched at least at a part of the slit and the upper peripheral edge, and the sandwich scissors are sandwiched between the upper edge of the powder container and the lower edge of the classification chamber of the classification means Thus, the classification device characterized in that the vibration hopper is held in a suspended state .
(2) The classification device according to item (1), wherein the powder is an electrophotographic powder .
(3): The slit length (P) is 1 / 10H ≦ P ≦ 9 / 10H with respect to the hopper height (H), wherein the item (1) or the item (2) is characterized. Classification device according to.
(4) The classifying device according to any one of (1) to (3), wherein the interval between the slits divides the hopper circumference into two to eight.
(5): The classification device according to any one of (1) to (4), wherein a cyclone collector is used as the classification means.
(6): the classification unit includes a dispersion chamber, and a classifying chamber underneath, the dispersion chamber, the dispersion chamber inlet for introducing a fluid mixture of powder material and the primary air, the internal An exhaust pipe for discharging gas, and the classification chamber has a secondary air flow inlet for introducing a secondary air flow from the peripheral portion, a conical center core, and a lower outer periphery of the center core. A fine powder that has a separator core provided, a coarse powder lowering port provided in a peripheral region, and a fine powder lowering port provided in a central region, and the hopper discharges fine powder guided from the fine powder lowering port. Item (1) to Item (1) , wherein a discharge port and a coarse powder discharge port for discharging coarse powder from the coarse powder descending port are provided, and a vibrating part is arranged in a suspended state in the hopper. The classification device according to any one of (5) .
(7): The classification device according to any one of (1) to (6), wherein the vibration section is formed of a conductive material.
(8) The classification device according to any one of (1) to (7), wherein a surface of the vibrating portion is formed of a release agent.
(9) The classification device according to any one of (1) to (8), wherein a surface of the vibration part is formed of a conductive release agent.
(10) The classification device according to any one of (1) to (9), wherein the surface of the vibration unit is polished.
(11) The surface area (S1) of the vibrating portion is any of the items (1) to (10) characterized by the following range with respect to the surface area (S) of the inner wall surface of the hopper: The classifier described;
0.30 × S ≦ S1 ≦ 0.99 × S
(12) A method for classifying an electrophotographic powder, characterized in that the classification apparatus according to any one of (1) to (11) is used.

As will be understood from the following detailed description, the present invention eliminates the adhesion of powder stored in the container by the vibrating part, facilitates moving storage of the powder, and also allows the powder stored in the container by the vibrating part. Since the adhesion of the body is eliminated, the powder state in the container is stabilized, the quantitative property of the feeder is improved, and the adhesion of the powder stored in the container by the vibrating part is eliminated, so that the hopper utilizing this function The powder state is stable, and the performance of ancillary equipment using this machine is improved.
Further, according to the present invention, it is possible to move and store in the hopper without changing the state of the powder supplied quantitatively from the feeder, and the performance of the filter type filtration device can be maintained over a long period of time. The powder adhesion is eliminated, stable classification accuracy is maintained for a long time, the suspended state of the vibration hopper can be easily mounted, and workability is greatly improved.

In addition, by using the device of the present invention, vibrations are transmitted over a wide range with minute vibrations, and classification accuracy is improved and can be stably maintained. Also, toner adhesion due to frictional charging is eliminated and static electricity is prevented. Therefore, safety can be secured, the releasability of the surface of the vibration hopper is improved, classification accuracy is maintained for a long time, and adhesion in the classification hopper is eliminated in a wide range.
Further, by using the apparatus of the present invention, toner adhesion with high frictional charge or adhesion is also eliminated, safety and releasability are greatly improved, and adhesion in the classification hopper is eliminated in a wide range, and the apparatus Adhesion can be freely removed regardless of whether or not the apparatus is in operation, and adhesion can be removed and removed in a wide range regardless of whether or not the apparatus is in operation.

  Further, by using the toner using the apparatus of the present invention, a sharp toner with less skipping can be obtained, and by using the apparatus of the present invention, a classified toner having a high product recovery rate can be obtained. Is demonstrated.

Hereinafter, in order to facilitate understanding of the present invention, the details of a conventional airflow DS classifier and apparatus will be described with reference to FIG. 1 (and the numbers after each name in the following text are figures). Corresponding to the numbers inside).
In FIG. 1, the airflow type DS classifier is composed of a dispersion chamber (5), a classification chamber (4), and a hopper (3) from the top, and the junction between the dispersion chamber (5) and the classification chamber (4) is It is detachably joined by being held in the upper casing (1), and the joint between the classification chamber (4) and the hopper (3) is detachable by being held in the lower casing (2). Joined freely.

  A dispersion chamber inlet (6) for supplying the primary air flow and the powder material is connected to the upper outer peripheral surface of the dispersion chamber (5) as an inflow from the peripheral surface, and exhaust for discharging the internal gas. A tube is provided. A conical center core (7) having a high center is attached below the dispersion chamber (5), and a separator core (10) for guiding fine powder around the lower edge of the center core (7); An annular coarse powder lowering port (11) is formed around the periphery, a fine powder lowering port (9) is provided in the central area, and the hopper (3) receives coarse powder from the coarse powder lowering port (11). A coarse powder discharge port (13) for discharging and a fine powder discharge port (14) of a fine powder discharge pipe (9a) for discharging the fine powder guided from the fine powder lowering port (9) are provided.

  In addition, a secondary air inlet (12) in which a flow path for the secondary air flow into the lower peripheral wall outer peripheral edge of the classification chamber (4) is partitioned into a plurality of small regions by a wing-shaped partition plate (Also called a louver) is provided in at least one place, and is configured to disperse the powder material and accelerate the turning speed.

  The classification principle of the airflow DS classification method is that when the secondary air flow that flows in the classification chamber causes the powder material to swirl counter-freely, the difference in mass between coarse particles and fine particles causes the circular motion of the particles. By multiplying the acceleration constant based on (swirl flow) (multiplying the square of acceleration by the mass) and making a large difference (mechanical difference), the powder material is utilized because it is easier to separate. It utilizes the fact that centrifugal force (and centripetal force) acting on the coarse particles and fine particles inside is different. Accordingly, the coarse particles and fine particles dispersed in the classification chamber are quickly classified without adhering to the inner wall of the apparatus or re-aggregating, and the coarse particles lose their kinetic energy and are discharged from the discharge port (13). Is preferably discharged from the discharge port (14).

Next, embodiments of the present invention will be shown.
[1] FIG. 7 shows an outline of one method of the present invention.
In the present invention, the adhesion strength of the powder adhering to the inner wall of the container (19) or the hollow housing is reduced by the vibrating section (20) to prevent the adhesion, and the separated coarse particles are quickly dropped to the bottom of the container. . As will be described later, the vibrating section (20) can be a hopper-shaped vibrating section in some cases, and is preferable.

[2] FIG. 11 shows an outline of an example of the powder processing method using the feeder of the present invention.
The powder input from the input port (29-1) is discharged to the discharge port (29-3) by the discharge screw (29-2), but the adhesion strength of the powder adhering to the inner wall of the feeder is determined by the vibrating portion (29 ) To prevent adhesion and quickly discharge the separated particles to the discharge port (29-3).

[3] FIG. 8 shows an outline of an example of a powder processing method using the hopper of the present invention.
The coarse particles separated by preventing the adhesion by lowering the adhesion strength of the powder that is primarily stored and adhered to the inner wall of the hopper container (20A) by the vibration part (21) and the vibration part (22) of the hopper part (20C). Is quickly dropped onto the bottom of the container (20B).

[4] FIG. 11 shows an outline of an example of a powder processing method using a hopper having a feeder according to the present invention at the bottom. In the system of this example, unlike the previous system having the vibration part in the container (20A), the container (20A) has the vibration part (27), and the hopper (20C) has the vibration part (28).
The powder input from the input port (27-1) is discharged to the discharge port (27-3) by the discharge screw (27-2). The adhesion strength of the powder adhering to the feeder inner wall is controlled by the vibrating portion (27). ), (28) to prevent adhesion and quickly discharge the separated particles to the outlet (27-3).

[5] FIG. 9 shows an outline of an example of a filtration method using a filter-type filtration device using a container in which the vibration unit is suspended in the interior of the present invention.
After the powder fluid flowing in from the inflow port (23-1) is adsorbed by the internal filter (23-3), the fluid (air flow) is discharged from the air discharge port (23-2). The adsorbed powder falls by its own weight by the cleaning air injected into the filter (23-3) from the injection port (23-5) at the top of the container (23A), and the discharge port (23-4) below the hopper (23C). More drain. The adhesion strength of the powder attached to and adhered to the inner wall of the filter filtration device is reduced by the vibrating portion (23) to prevent the adhesion, and the powder is also hopper (23C) by the vibrating portion (24) disposed in the hopper (23C). ) And quickly discharged from the powder discharge port (23-4) without remaining on the inner wall.
In order to dispose the vibrating part (24) in a suspended state in the container (23A), for example, a pinch is provided on at least a part of the upper peripheral edge of the vibrating part (23), and the pinch is attached to the hopper. It can be placed in a suspended state by being sandwiched between the upper edge and the lower edge of the classifying chamber, or can be supported on the inner wall surface of the container (23A) using a suitable elastic suspension member. Can also

[6] FIG. 13 shows an example of a rotary rotor classification as an example of a classification method using a classification device provided with a hopper using a container with a vibrating part and a classification S 裡 means according to the present invention. The classification material supplied from the inclined material supply port (30) is located in the upper part of the apparatus, and the coarse powder is positioned downward by the centrifugal force of the rotating classification rotor (31) and the centripetal force of the air volume sucked from the inside. The fine powder is discharged from the coarse powder outlet (33), and the fine powder is discharged from the fine powder outlet (32) located above. At that time, since the vibration part (34-1) is mounted on the classifier hopper (34), coarse particles do not stay in the machine, and stable classification accuracy is maintained. As long as the classifier is provided with a hopper and classification means and satisfies the requirements of the present invention, there is no definition of the system and structure.

[7] In the present invention, the “dispersion chamber, the classification chamber below it, and the powder classification device having the hopper below it”, that is, the “dispersion chamber, the classification chamber below it, and the A powder classification apparatus having the hopper, wherein the dispersion chamber includes a dispersion chamber inlet for introducing a fluid mixture of the powder material and primary air, and an exhaust pipe for discharging the internal gas. The classification chamber has a secondary air flow port for introducing a secondary air flow from the peripheral portion, a conical center core, a separator core provided on the lower outer periphery of the center core, and a peripheral region. A coarse powder lowering port provided in the center area, and the hopper includes a fine powder discharge port for discharging fine powder guided from the fine powder downward port, and the coarse powder lowering port. A coarse powder outlet is provided for discharging the coarse powder, and the vibrating part is suspended in the hopper. For classifying apparatus of the powder, characterized in that the "shows the outline in FIG.

In the following description, each name not shown in the corresponding figure and the number after that name are the same as those in FIG. 1 and other figures.
The characteristics of the classifier of the present invention are shown below.
In the airflow type DS classifying apparatus shown in FIG. 2, a vibrating part (3a) (made in this example a hopper) made by a sheet-like plate thickness of 0.3 to 3.0 mm inside a hopper (3) which is an object of the present invention. If there is no vibrating part (3a), the adhesion strength of the powder adhering to the inner wall of the hopper (3) is reduced by vibration to prevent adhesion, and the separated coarse particles are discharged quickly. Guide to (13).

  The details of the vibration part (3a) will be described with reference to the three-dimensional view of FIG. 3 (A). Thus, it has a structure that easily resonates to the vibration part (3a) by vibration of the classifying device. The jig connected to the hopper (3) only needs to be able to easily transmit vibration, and other materials such as rubber and silicon can be used, and there is no particular limitation.

With the cantilever structure, the hopper-shaped vibrating part (3a) vibrates the classifier main body and affects the classification accuracy. By using the cantilevered hopper-shaped vibrating part (3a) Since the vibration surface (hopper surface) vibrates with less energy without vibrating the classifier body, the adhesion strength of the particles can be reduced and adhesion can be prevented.
The connecting portion of the vibrating portion (3a) with the hopper (3) is fixed, and a plate thickness of 0.3 to 3.0 mm is preferable in terms of resonance with respect to natural vibration.

  A vibrator (V) is generally used as a vibrator for the vibrating part (3a). This vibrator includes a mechanical type using an electromagnetic action or an air type using a piston or a rotary type, and the air rotary type is used as a mainstream, judging from safety, functionality and operability. The vibration mode is effective for both continuous and intermittent operation, but intermittent operation is used as the mainstream in consideration of noise or energy consumption.

[8] The airflow DS classifier of the present invention shown in FIG. 2 is shown in FIGS. 4 (A) and 5 (A) (detailed view).
Here, the vibrating part has a scissors on at least a part of the upper peripheral edge, and the scissors are sandwiched between the upper edge of the hopper and the lower edge of the classification chamber (removably). In the case where the vibrating hopper is held in a suspended state, an example will be described. Such a classifying device is provided with a scissors (3C) sandwiched between the upper edges of the vibrating portion (3a) to be mounted, By sandwiching the pinch white (3C) between the upper edge of the hopper (3) and the lower edge of the classification chamber (4), the vibrating part (3a) is held in a suspended state.
FIG. 4B shows another preferred example of a specific method for attaching the pinch scissors. A scissors (3c) is detachably set and fixed between the lower surface of the secondary air inlet member (12) at the lower edge of the classification chamber (4) and the upper edge surface of the hopper (3). Since the vibrating part (3a) is cantilevered and fixed in the hopper (3) by the vibrating part (3a) and the pinch scissors (3c), the vibration is easily transmitted to the entire vibrating part (3a).

[9] A device in which a slit is attached to the vibration part (3a) according to the present invention is provided on the side surface of the vibration part (3a) to be attached in the classification devices of (7) and (8). The classifying apparatus is characterized in that one to ten slits (3S) shown in (B) are attached to the side surface of the vibrating section (3a).
The installation position (P) of the slit (3S) is 1 / 10H ≦ P ≦ 9/10 with respect to the hopper height (H), and the interval between the slits (3S) is 2-8 divisions with respect to the hopper circumference. Is easier to communicate.

[10] In the apparatus in which the vibration part (3a) in the present invention is formed of a conductive material, the material of the vibration part (3a) of [7] to [9] is made of a conductive metal. This prevents the powder from adhering due to frictional charging.
As a specific conductive metal, SUS, Al, Cu, SS material or the like is generally used, but is not limited.

[11] The apparatus in the case where the vibration part (3a) in the present invention is formed of a releasable material is generated by subjecting the material surface of the vibration part (3a) to a release agent treatment and pulverization. It is an airflow type pulverizing / classifying machine characterized by suppressing adhesion, aggregation, fusion, and adhesion in the apparatus.
The conductive mold release agent treatment is, for example, in the range of an electric resistance value of 10 ³ to 10 ¹⁶ Ω · cm and a volume resistance value of 10 ³ to 10 ¹⁶ Ω · cm, and the electric resistance value is mainly 10 ⁶ to 10 ⁹ Ω. Basic fluororesin that is cm: PTFE (Teflon: registered trademark), PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), FEP (tetrafluoroethylene-hexafluoropropylene copolymer), ETFE (tetral) A vibration hopper is coated with a fluoroethylene-ethylene copolymer).

[12] The apparatus in the case where the vibration part (3a) in the present invention is made of a conductive releasable material, the vibration part (3a) has both conductivity and releasability. It is characterized by a classifier that is mounted on a hopper (3).

[13] In the apparatus when the surface of the vibration part (3a) in the present invention is polished, the material surface of the vibration part (3a) is subjected to polishing treatment such as blasting, and the uneven surface is Ra0. 0.05 to 1.0 μm, Ry 1.0 to 5.0 μm, Rz 1.0 to 5.0 μm, Rq Ra 0.05 to 1.0 μm.
As a polishing method, dry blasting is generally performed in which a surface is irradiated with high-pressure air on a medium of 5 to 50 μm fine metal powder or resin beads.

[14] In the present invention, the surface area (S1) of the vibrating portion (3a) is in the range of [0.30 × S ≦ S1 ≦ 0.99 × S] with respect to the surface area (S) of the inner wall surface of the hopper. The classifying device is characterized in that the vibrating part (3a) in the classifier can be completely attached and removed in accordance with the powder characteristics, so that the vibrating part (3a) with respect to the surface area (S) of the hopper (3) can be removed. The shape, particularly the surface area (S1), is preferably 0.30 × S ≦ S1 ≦ 0.99 × S, and most desirably is characterized by a range of 0.6 × S ≦ S1 ≦ 0.9 × S. This is a classification device.

[15] In the classifying apparatus according to the present invention, a vibrator capable of self-vibration is provided in the vibrating section (3a). The classifying apparatus includes a vibrator (V) shown in FIG. 6 on the outer surface of the vibrating section (3a) in the classifier. The vibration part (3a) is capable of self-vibration.
For example, in addition to an air vibration vibrator such as an ABB company netter pneumatic turbine vibrator, an electric vibration vibrator or the like is generally used, but the invention is not limited to this.
The range of the vibrator is a frequency (number of times / min) of 3000 to 25000 min-1, preferably 7000 to 23000 min-1, and the range of vibration force (1N = 0.102 kg) is 1000 to 4000 N, preferably 1500 to 3000 N. .

[16] The vibrator mounting position (VS) in this case is in the range of [0.3 × H ≦ VS ≦ 0.8H] with respect to the height (H) of the vibrating portion (3a) shown in FIG. 6, preferably It is desirable to be in the range of [0.5 × H ≦ VS ≦ 0.6H]. If the vibrator attachment position (VS) is mounted in the HS direction smaller than 0.3 × H, vibration cannot reach the vibration vibrator and sufficient vibration cannot be transmitted. On the other hand, if it is larger than 0.8H, the amplitude to the vibration hopper becomes large, which interferes with the classification hopper (3), and noise and metal wear occur.
A vibrator is generally used as the vibrator. This vibrator includes a mechanical type using an electromagnetic action or an air type using a piston or a rotary type, and the air rotary type is used as a mainstream, judging from safety, functionality and operability. The vibration mode is effective for both continuous and intermittent operation, but intermittent operation is used as the mainstream in consideration of noise or energy consumption.

[17] A case where a cyclone collector is used as the classification device in the present invention will be described with reference to FIG.
The pulverized fluid that flows in the tangential direction from the pulverized fluid inlet (25-1) provided on the outer periphery of the device acts by centrifugal force due to the swirling flow effect of the cyclone, and the powder swirls on the inner wall surface, and the fluid (air flow) is above the device It is made to discharge from the air discharge port (25-2) provided in. The powder falls by its own weight while continuing to swivel and is discharged from the powder discharge port (25-3) provided at the lower part of the apparatus. The adhesion strength of the powder adhering to the inner wall of the collection container cyclone is controlled by the vibrating portion (25 ) And (26) to prevent adhesion and quickly drop the separated coarse particles to the bottom of the cyclone container.

Hereinafter, the situation classified with the classifier of this invention is shown concretely.
These are only one aspect of the present invention, and the technical scope of the present invention is not limited thereto.
The operating time is constant, and the efficiency is shown by operating until the degree of classification in that case or a certain condition.

Reference example 1 (container in which the vibrating part (3a) is suspended in a suspended state, an example of using a feeder using the container)
A mixture of 70% by weight of styrene-acrylic copolymer resin, 10% by weight of polyester resin and 5% by weight of Carnauba WAX was melt kneaded with a roll mill, cooled and solidified, and then coarsely pulverized with a hammer mill.
Next, this coarsely pulverized product is finely pulverized to a particle size of 6.4 μm by a jet mill, and the finely pulverized product is put into a container. Using.
There was no toner adhesion or segregation on the inner wall of the container or feeder.

Reference Example 2 ( Example of use of filter type filtration device)
A mixture of 70% by weight of styrene-acrylic copolymer resin, 10% by weight of polyester resin and 5% by weight of Carnauba WAX was melt kneaded with a roll mill, cooled and solidified, and then coarsely pulverized with a hammer mill.
Next, this coarsely pulverized product was finely pulverized to a finely pulverized particle size of 6.0 μm with a jet mill to obtain a finely pulverized product.
Vibration conditions, etc .: A frequency of 21000 min −1 and a vibration force range of 2200 N were used.
The finely pulverized product was classified with an airflow DS classifier shown in FIG.
A number content of 10% was obtained with ultrafine particles having a weight-pulverized particle size of 6.4 μm and 4 μm or less.
The above pulverized and classified products are pulverized using the filter type filtration device shown in FIG. 9, and vibration conditions are the same as in the classification step: the frequency is 21000 min-1, the range of vibration force is 2200 N. Body discharge was 99.5%.

Reference Example 3 (Usage example of a classification device having a cyclone collector as a classification means)
A mixture of 70% by weight of styrene-acrylic copolymer resin, 10% by weight of polyester resin and 5% by weight of Carnauba WAX was melt kneaded with a roll mill, cooled and solidified, and then coarsely pulverized with a hammer mill.
Next, this coarsely pulverized product was finely pulverized to a weight-pulverized particle size of 6.4 μm with a jet mill to obtain a finely pulverized product.
Vibration conditions, etc .: A frequency of 21000 min −1 and a vibration force range of 2200 N were used.
The finely pulverized product was classified with an airflow DS classifier shown in FIG.
A number content of 8% was obtained with ultrafine particles having a weight-pulverized particle diameter of 6.8 μm and 4 μm or less.
The above pulverized and classified products are pulverized using the cyclone shown in FIG. 10, and vibration conditions are the same as in the classification process: the frequency is 21000 min-1, the range of vibration force is 2200 N. 0%.

Reference Example 4 (Usage example of a container hopper having a lower feeder and a vibrating part (3a) arranged in a suspended state)
A mixture of 70% by weight of styrene-acrylic copolymer resin, 10% by weight of polyester resin and 5% by weight of Carnauba WAX was melt kneaded with a roll mill, cooled and solidified, and then coarsely pulverized with a hammer mill.
Next, the coarsely pulverized product was finely pulverized with a jet mill to a weight pulverized particle size of 6.4 μm to obtain a finely pulverized product, using the feeder shown in FIG. 11;
Vibration conditions, etc .: Using a frequency of 20000 min-1 and a vibration force range of 2100 N, classification was performed by supplying the airflow DS classifier shown in FIG.
A number content of 9% was obtained with ultrafine particles having a weight-pulverized particle size of 6.8 μm and 4 μm or less.

Reference Example 5 (Usage example of a classifier equipped with a vibrator in the vibrating part (3a))
A mixture of 70% by weight of styrene-acrylic copolymer resin, 10% by weight of polyester resin and 5% by weight of Carnauba WAX was melt kneaded with a roll mill, cooled and solidified, and then coarsely pulverized with a hammer mill.
Next, this coarsely pulverized product was finely pulverized to a weight-pulverized particle size of 6.4 μm with a jet mill to obtain a finely pulverized product.
Vibration conditions, etc .: A frequency of 21000 min −1 and a vibration force range of 2200 N were used.
This finely pulverized product was classified with an airflow DS classifier shown in FIG.
A number content of 8% was obtained with ultrafine particles having a weight-pulverized particle diameter of 6.8 μm and 4 μm or less.

Comparative Example 1
As a result of classification using the current classifier shown in FIG. 1 under the same conditions as in Example 5, a number content of 10% was obtained with very fine particles having a weight-pulverized particle size of 6.90 μm and 4 μm or less in one hour of operation. After 2 hours, the number content of ultrafine particles of 4 μm or less increased to 12%. As a result of checking the inside of the apparatus, toner adhesion was confirmed in the hopper.

Example 1 (Usage example of the airflow type DS classifier shown in FIG. 2)
The finely pulverized product obtained through the same kneading and pulverization as in Reference Example 5 was classified using the airflow DS classifier shown in FIG.
A number content of 8% was obtained with ultrafine particles having a weight-pulverized particle diameter of 6.8 μm and 4 μm or less.

Example 2 ((Usage example of the airflow type DS classifier shown in FIG. 4)
The finely pulverized product obtained through the same kneading and pulverization as in Reference Example 5 is classified by the airflow DS classifier shown in FIG. 5% was obtained.

Example 3 (Usage example of a classifier having a vibrating part (3a) formed of a conductive material)
The finely pulverized product obtained through the same kneading and pulverization as in Reference Example 5 was operated for 10 hours using a vibration hopper made of a copper plate having a conductivity of 95%, and the finely pulverized particle size was 6.85 μm and ultrafine particles of 4 μm or less. A number content of 8% was obtained.

Example 4 (Usage example of a classifier having a vibrating part (3a) formed of a conductive release agent material)
A finely pulverized product obtained by kneading and pulverizing in the same manner as in Reference Example 5 was manufactured using a copper plate having a conductivity of 95%, and then coated on a fluororesin vibration hopper having an electric resistance of 108 Ω · cm and a volume resistance of 106 Ω · cm The mixture was operated for a while, and a number content of 7.5% was obtained with ultrafine particles having a weight-pulverized particle size of 6.8 μm and 4 μm or less.

Example 5 (Usage example of a classifier having a vibration part (3a) subjected to blast polishing)
After a finely pulverized product obtained by kneading and pulverizing in the same manner as in Reference Example 5 was produced with a copper plate having a conductivity of 95%, the uneven surface was changed to Ra 0.10 μm, Ry 3.0 μm, Rz 3.0 μm, Rq Ra 3.0 μm. It was operated for 15 hours using a blasted vibration hopper, and a number content of 7.0% was obtained with extremely fine particles having a weight-pulverized particle size of 6.8 μm and 4 μm or less.

Reference Example 6 (Usage example of a classification device in which the vibrator mounting position (VS) and the height (H) of the vibration hopper are in the relationship of [0.3 × H ≦ VS ≦ 0.8H] shown in FIG. 6)
The finely pulverized product obtained through the same kneading and pulverization as in Example 5 was operated for 15 hours using a vibration hopper surface area (S1) of 0.8 × S with respect to the hopper surface area (S). A number content of 7.0% was obtained with ultrafine particles of 7 μm and 4 μm or less.

Reference Example 7 (Usage example of a classifier equipped with a vibrator that can vibrate on the vibrating part (3a))
The finely pulverized product obtained through the same kneading and pulverization as in Reference Example 5 was operated in a vibration hopper for 15 hours using a frequency (number of times / min) of 22500 min-1, a vibration force of 500 to 5000 N, and a weight pulverized particle size of 6 A number content of 7.0% was obtained with ultrafine particles of 7 μm and 4 μm or less.

Reference Example 8 Example of use of classification device in which vibrator mounting position (VS) and vibration hopper height (H) are in a relationship of [0.3 × H ≦ VS ≦ 0.8H]
A finely pulverized product obtained through the same kneading and pulverization as in Reference Example 5 is mounted on a vibration hopper at 0.5 H from the HS direction with respect to the height H of the hopper, and the vibration frequency (frequency / min) of the vibrator is 22500 min-1, The vibration force was operated for 15 hours using 500 to 5000 N, and a number content of 6.5% was obtained with ultrafine particles having a weight-pulverized particle size of 6.7 μm and 4 μm or less.

It is a figure which shows the conventional classification apparatus. It is a figure which shows the classification apparatus of this invention. (A) is an enlarged view of the hopper part of this invention, (B) is an enlarged view (slit) of the hopper part of this invention. (A) is a classification device (pinching white) of the present invention, and (B) is a mounting view of a vibration hopper of the present invention. (A) is an enlarged view of the hopper portion of the present invention (pinching white), and (B) is an enlarged view of the hopper portion with a slit pinch of the present invention. It is an enlarged view (vibration device) of the hopper part of this invention. The vibration part of the present invention is a container showing the mounting of (20), 20-a is a three-dimensional view of the vibration part, and 20-b is a slit-type three-dimensional view. The vibration part of the present invention is a hopper showing attachment of (21), 21-a, 22-a are three-dimensional views of the vibration part, 21-b, 22-b are slit-type three-dimensional views. The filter type filtration device 23-a, 24-a showing the attachment of the vibration part (23) of the present invention is a three-dimensional view of the vibration part, 23-b, 24-b are slit-type three-dimensional views. The vibrating part of the present invention is a collection container cyclone showing the mounting of (25), 25-a and 26-a are three-dimensional views of the vibrating part, and 25-b and 26-b are slit-type three-dimensional views. It is a figure which shows an example of the feeder mounting | wearing of this invention. It is a figure which shows the other example of the feeder mounting | wearing of this invention. It is a figure which shows an example of the rotary rotor classification | category of this invention.

Explanation of symbols

1: Upper casing part 2: Lower casing part 3: Hopper 3a: Vibrating part 3b: Spring 3C: Scissors white 3S: Slit 4: Classification room 5: Dispersion room 6: Classification room inlet 7: Center core 9: Fine powder lowering hole 9a: Fine powder discharge pipe 10: Separator core 11: Coarse powder lowering port 12: Secondary air inlet 13: Coarse particle discharge port 14: Fine particle discharge port 17: Exhaust pipe 20: Vibrating part 20A: Container 20B: Container bottom part 20C: Hopper part 21: Vibrating part 22: Vibrating part 23: Vibrating part 23A: Container 23C: Hopper 23-3: Filter 23-2; Air outlet 23-3: Filter 23-4: Powder outlet 23-5: Injection Port 24: Vibrating unit 25: Vibrating unit 25A; Container 25-1: Powder fluid inlet 25-2: Air outlet 25-3: Powder outlet 26: Vibrating unit 26A: Hopper unit 27: Vibrating unit 27-1 :powder Inlet 27-2: Powder discharge screw 27-3: Discharge port 27-1: Particle discharge port 23-1: Powder fluid inlet 28: Vibrating unit 29: Vibrating unit 29-1: Powder inlet 29-2: Powder discharge screw 29-3: Particle discharge port 30: Material supply port 31: Classification rotor 32: Fine powder discharge port 33: Coarse powder discharge port 34: Classifier hopper 34-1: Vibration part H: High vibration part & hopper height S: Surface area of hopper V: Vibrator S1: Surface area of vibration part VS: Vibrator mounting position HS: Vibrator mounting position reference P: Slit mounting position

Claims (12)

A classification apparatus comprising a classification means and a powder container for temporarily storing powder under the classification means , wherein the powder container has a hopper-shaped vibration part that vibrates due to vibration of the classification means, The vibrating part has a scissors on at least a part of the slit and the upper peripheral edge, and the scissors are sandwiched between the upper edge of the powder container and the lower edge of the classification chamber of the classification means, A classification device characterized in that the vibration hopper is held in a suspended state . The classification device according to claim 1, wherein the powder is an electrophotographic powder . The classification device according to claim 1, wherein the slit length (P) is 1 / 10H ≦ P ≦ 9 / 10H with respect to the hopper height (H). The classifying apparatus according to any one of claims 1 to 3, wherein the interval between the slits divides the hopper circumference into 2 to 8 parts. The classification device according to any one of claims 1 to 4 , wherein a cyclone collector is used as the classification means. The classification unit comprises: a dispersion chamber, and a classifying chamber underneath, the dispersion chamber is discharged and the dispersion chamber inlet for introducing a fluid mixture of powder material and the primary air, an interior gas The classification chamber has a secondary air flow inlet for introducing a secondary air flow from the peripheral portion, a conical center core, and a separator provided on the lower outer periphery of the center core. A core, a coarse powder lowering port provided in the peripheral region, and a fine powder lowering port provided in the central region, and the hopper has a fine powder discharge port for discharging fine powder guided from the fine powder lowering port; it has a coarse powder discharge port for discharging the coarse powder from the coarse powder falling opening, into the hopper, according to any one of claims 1 to 5, characterized in that arranged in a state suspended the air vibration unit Classification device. The classification device according to any one of claims 1 to 6 , wherein the vibration section is made of a conductive material. The classifying apparatus according to claim 1, wherein a surface of the vibration part is formed of a release agent. The classifying apparatus according to claim 1, wherein the surface of the vibration part is formed of a conductive release agent. Wherein the surface of the vibrating portion, the classification apparatus according to any one of claims 1 to 9, characterized in that it is polished. The classification device according to any one of claims 1 to 10 , wherein the surface area (S1) of the vibrating portion has the following range with respect to the surface area (S) of the inner wall surface of the hopper.
0.30 × S ≦ S1 ≦ 0.99 × S 12. A method for classifying an electrophotographic powder, characterized in that the classification apparatus according to claim 1 is used.

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