Ricoh Company, Ltd.

Ricoh UK Products Ltd.

Nobuyasu Makino

Fumitoshi Murakami

Tetsuya Tanaka

Mutsumi Takahashi

Yasuaki Iwamoto

Masakazu Nakada

Kazuyuki Yazaki

Ryoichi Ito

Makoto Hirai

Kouji Noge

Tomotsugu Miyamoto

Kazuo Kuratani

Mitsuyoshi Izu

Hideyuki Santo

Satoshi Okano

Satoru Miyamoto

Tohru Suganuma

Kenichi Uehara

Natsuko Matsushita

Hiroyuki Yoshikawa

Kazuyuki Matsui

Kohji Kubota

Shoji Watanabe

Kohta Wakimoto

Toshiyuki Fukase

Masakazu Yashiro

Eiichi Masushio

Eisuke Sugisawa

Keiko Watanabe

Shinji Hirata

Nagaki Sato

Shigeaki Kakuda

Tsutomu Kagawa

David Roberts

Colin Weaver

Kenta Kawasumi

A classifying apparatus including a cylindrical casing, a powder material feeding port, a louver ring disposed in the casing to be in communication with the powder material feeding port in a horizontal direction, a center core, a separator core, a dispersion chamber defined by the center core and an inner wall of the casing at the powder material-fed side, a classification chamber defined by the center core, the separator core and a side inner wall of the casing, and a flow path encircling the louver ring, wherein in a horizontal cross section of part of the classifying apparatus where the part contains the powder material feeding port and the louver ring, the louver ring is located at a position where the louver ring does not intersect with an extended line of a wall surface of the powder material feeding port at the side of the louver ring.

Classifying apparatus, classifying method, toner and method for producing the toner

The pulverizer including a pulverization chamber, a jet nozzle, a pulverization nozzle, and a collision member is provided. The pulverization nozzle includes an acceleration tube. The acceleration tube includes an acceleration part A and an acceleration part B. A center (a) of the supply aperture is positioned within the acceleration part A. A point of intersection (b) where central axes of the acceleration tube and the supply aperture intersect is positioned within the acceleration part B. An angle &#x3b8; formed between the central axes of the acceleration tube and the supply aperture satisfies an inequation 30&#xb0;&#x2266;&#x3b8;&#x3c;60&#xb0;.

Pulverizer

A pulverizer, including a spray nozzle to spray airstream; a pulverization chamber to pulverize a subject with the airstream; and a cylindrical adaptor to be fitted to the spray nozzle, including a flow path to pass the airstream sprayed from a front end face of the spray nozzle, including an inlet hole to inhale the subject pulverized in the pulverization chamber into the flow path on a side wall thereof, wherein the front end face of the spray nozzle and a rear end face of the inlet hole are located on the same plane when the cylindrical adaptor is fitted to the spray nozzle.

Pulverizer and cylindrical adaptor

A classification device for classifying particles by size including an upper impeller-type rotor, a first end of which is covered with a cover disc without penetration hole and a second end of which is covered with an upper cover disc with a penetration hole; and a lower impeller-type rotor, a first end of which is covered with a cover disc without penetration hole and a second end of which is covered with a lower cover disc with a penetration hole. The upper impeller-type rotor and the lower impeller-type rotor are provided so that axes thereof are coincident and the first ends face with each other forming a gap therebetween in an axial direction, and the diameters of the penetration holes of the upper cover disc and the lower cover disc are different.

Classification device

An air classifier contains a cylindrical casing provided with at an upper part thereof a feed port to feed high pressure air and a powder material, an umbrella-shaped center core in the casing, and an umbrella-shaped separator core arranged downstream of the center core in the casing and including an opening at center thereof. The air classifier has a configuration containing a dispersion chamber to disperse the powder material, being surrounded by an inner wall of the upper part casing and the center core, and a classification chamber to classify the powder material into fine and coarse powders by centrifugation, being surrounded by the center core, separator core and inner wall of the casing. In the dispersion chamber provided are a louver ring containing guide slats circularly arranged at regular intervals, and a space encircling the louver ring and serving as flow passage of the air and powder material.

Air classifier

A method for producing powder including supplying a powder material to a fluidized bed container, jetting fluid from each of a plurality of fluid jetting nozzles provided in the fluidized bed container to collide against each other, thereby fluidizing and pulverizing the powder material in the fluidized bed container to form powder, classifying the powder using a centrifugal classification rotor provided at the upper part of the fluidized bed container and discharging the classified powder from an outlet by being guided by the centrifugal classification rotor, wherein the centrifugal classification rotor is rotated at a first rotating speed for a predetermined time from the beginning of the flow of the powder material in the fluidized bed container, and at a second rotating speed after the predetermined time has passed, and the centrifugal classification rotor is controlled so that the first rotating speed is higher than the second rotating speed.

Method for producing powder and fluidized bed pulverizing apparatus

The airflow classifier includes a dispersing chamber dispersing a powdery raw material with high pressure air; a classifying chamber located below the dispersing chamber and including a center core located on an upper portion thereof and a separator core having an opening at a center thereof and located on a lower portion of the classifying chamber to subject the raw material, which is fed from the dispersing chamber, to centrifugal classification to classify the raw material into coarse particles and fine particles; a fine particle feeding pipe connected with a lower portion of the opening of the separator core; a shield ring to cover an upper portion of the opening; and a louver pipe which is located above the shield ring and in which plural blades are arranged on an edge of the opening at predetermined intervals.

Airflow classifier and particulate material preparing apparatus using the airflow classifier

The airflow pulverization and classification device includes a pulverizer and a classifier. The pulverizer includes a pulverization chamber including a collision member; a jet nozzle directing jet flow toward the pulverization chamber; a feeder feeding a particulate material; a supply nozzle having an acceleration tube connected with the jet nozzle and the pulverization chamber, and a supply tube connected with the feeder and the acceleration tube to supply the particulate material the acceleration tube so that the particulate material is collided with the collision member; and a pressure gauge measuring a static pressure in the feeder and/or the supply tube, and/or a static pressure at the junction of the acceleration tube and the supply tube to control the supply conditions of the particulate material supplied to the acceleration tube on the basis of the measured static pressure.

Airflow pulverization and classification device, and pulverization method

To provide an electrophotographic toner pulverizing apparatus and an electrophotographic toner pulverizing method for preventing reduction in wear resistance of a rotor, a stator, and the like even in long-term pulverizing of toner. The electrophotographic toner pulverizing apparatus according to the present invention has a pulverizing chamber with at least a rotor and a stator disposed therein. The surface of at least one of the rotor and the stator has a chromium plated layer having Cr as a main component and containing Mg, Al, Si, Ti, Mn, Fe, and C elements.

Electrophotographic toner pulverizing apparatus and electrophotographic toner pulverizing method

A pulverizing and coarse powder classifying apparatus including: a mechanical pulverizer that pulverizes a powder raw material, a cyclone that collects pulverized powder, and a coarse powder classifier that separates coarse powder from the collected powder, wherein the coarse powder classifier is a cyclone classifier including a dispersion chamber equipped with a center core and used for dispersing the powder, and a classification chamber equipped with a separator core, and wherein the center core has at its center a fine powder discharge pipe.

Pulverizing and coarse powder classifying apparatus and fine powder classifying apparatus

The present invention provides a method for manufacturing particles, where a viscous material is sprayed with a high-pressure gas for atomization while the viscous material is being discharged in a chamber, and cooling air is introduced in the chamber for granulation. The present invention also provides a method for manufacturing a toner, where a mixture containing at least a binding resin and a colorant is melt mixed under pressure or melt mixed with an injection of a supercritical fluid, the obtained melt-mixed substance is sprayed with a high-pressure gas for atomization while the melt-mixed substance is being discharged in a chamber, and cooling air is introduced in the chamber from an air inlet formed on the chamber.

Particles and manufacturing method thereof, toner and manufacturing method thereof, and developer, toner container, process cartridge, image forming method and image forming apparatus

A pulverization/classification apparatus including a cylindrical vessel having an inner wall, on a surface of which a layer including a release agent is located; a pulverizer configured to pulverize a material such as toner raw materials in the cylindrical vessel using a compressed air to prepare a particulate material; and a classifier configured to classify the particulate toner material to prepare a powder of the material. Alternatively, the inner wall of the cylindrical vessel has a circumferentially projected portion. A method for manufacturing a powder such as toners using the pulverization/classification apparatus is also provided.

Pulverization/classification apparatus for manufacturing powder, and method for manufacturing powder using the pulverization/classification apparatus

To provide a method for producing a toner, containing a milling step containing finely milling particles and classifying coarse particles by using at least a mill and a cyclone unit, and a classifying step containing classifying pulverized particles by using at least a classifier and a cyclone unit, wherein any of the pulverized particles and other particles, which are classified by the classifier in the classifying step and returned, are returned to the cyclone unit in the milling step, and a toner produced by the method for producing the toner.

Toner and method for producing the same

A toner manufacturing process, includes: melting a kneaded composition, to thereby obtain a melted composition; and spraying the melted composition with a high pressure gas, to thereby form a fine particle. The kneaded composition is selected from the group consisting of the following &#x3c;1&#x3e;, &#x3c;2&#x3e; and &#x3c;3&#x3e;: &#x3c;1&#x3e; a first kneaded composition including a binder resin, a colorant, and a charge controlling agent, &#x3c;2&#x3e; a second kneaded composition including a binder resin, a colorant, a charge controlling agent, and a releasing agent, and &#x3c;3&#x3e; a third kneaded composition including a binder resin, a magnetic agent, a charge controlling agent, and a releasing agent.

Toner, process of manufacturing toner, developer, toner container, process cartridge, image forming apparatus, and image forming process

A pulverization/classification apparatus includes a plurality of air nozzles, a milling chamber as a space for pulverizing particles by compressed air jetted by the air nozzles, and a rotor installed at an upper part of the milling chamber that classifies powder materials flowing into the rotor from the milling chamber with centrifuging into fine particles and coarse particles. The rotor includes plural blade members, and a width of the blade members within the rotor are set to be 1/50- 2/25 of the rotor's diameter.

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Numazu, Japan

Nobuyasu Makino