Patents by Inventor Takayuki Koike

Takayuki Koike has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7116932
    Abstract: A developing unit includes a developer containing unit that contains developer, a developer carrier that has a moving surface, and carries the developer, a magnetic force generator that attracts the developer onto the moving surface by a magnetic force generated from a plurality of magnets, and a restricting member that restricts a layer thickness of the developer. The magnets includes a restricting magnet arranged closest to the restricting member and has a restricting magnetic pole of which a first surface toward the moving surface and a second surface toward an upstream adjacent magnet that is arranged so as to be adjacent to an upstream side of the developer carrier in a direction of movement of the moving surface and has an upstream adjacent magnetic pole form a ridged corner portion, and the ridged corner portion is chamfered.
    Type: Grant
    Filed: June 22, 2004
    Date of Patent: October 3, 2006
    Assignee: Ricoh Company, Limited
    Inventors: Nobutaka Takeuchi, Hajime Oyama, Hiromitsu Takagaki, Takayuki Koike
  • Patent number: 7103305
    Abstract: A developing apparatus which uses a two-component developer consisting of a toner and carrier. The ratio between the amount of the developer M1 which is drawn onto a developing sleeve and refluxes while being regulated by a doctor blade, and the amount of the developer (drawn amount) M2 which passes through the doctor blade is M1/M2<10. The toner is a negatively-charged toner. In a charge amount distribution the number of toners of ?1 fc/10 ?m or more is 20% or less of the total number of toners.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: September 5, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Takayuki Koike, Nobutaka Takeuchi, Nobuo Iwata, Satoshi Muramatsu, Junichi Matsumoto
  • Publication number: 20060140679
    Abstract: A developing apparatus for use in an image forming apparatus includes a developing roller, a developing agent, a refilling port, a transport member, and an agitation enhancer. The developing agent includes toner particles and carrier particles and is refilled to the developing apparatus from the refilling port. The transport member transports the developing agent to the developing roller while agitating the developing agent. The agitation enhancer is provided on a peripheral portion of the transport member to increase agitation movement of the developing agent.
    Type: Application
    Filed: December 12, 2005
    Publication date: June 29, 2006
    Inventors: Nobuo Iwata, Satoshi Muramatsu, Nobutaka Takeuchi, Junichi Matsumoto, Takayuki Koike
  • Publication number: 20060127136
    Abstract: A method of developing a latent image formed on an image carrier with toner, including causing a developer carrier, which faces the image carrier and accommodates a magnet therein, to support a developer having a toner and a magnetic carrier supporting the toner and convey the developer to a developing zone between the developer carrier and the image carrier, and providing an apparent coating ratio M of a surface of the developer carrier coated with the developer. The coating ration M is, in a zone upstream of the developing zone in a direction of rotation of the developer carrier, expressed as M=?A2+? (%), where a denotes a coefficient of the coating ratio, A2 denotes an amount of developer for a unit area, ? denotes a value determined by a powder characteristic of the developer for an apparent coating ratio calculated with A2=0, and the coating ratio M is between 90% and 120%.
    Type: Application
    Filed: February 8, 2006
    Publication date: June 15, 2006
    Inventors: Nobutaka Takeuchi, Hajime Oyama, Hiromitsu Takagaki, Takayuki Koike
  • Patent number: 7024141
    Abstract: A method of developing a latent image formed on an image carrier with toner, including causing a developer carrier, which faces the image carrier and accommodates a magnet therein, to support a developer having a toner and a magnetic carrier supporting the toner and convey the developer to a developing zone between the developer carrier and the image carrier, and providing an apparent coating ratio M of a surface of the developer carrier coated with the developer. The coating ration M is, in a zone upstream of the developing zone in a direction of rotation of the developer carrier, expressed as M=?A2+? (%), where ? denotes a coefficient of the coating ratio, A2 denotes an amount of developer for a unit area, ? denotes a value determined by a powder characteristic of the developer for an apparent coating ratio calculated with A2=0, and the coating ratio M is between 90% and 120%.
    Type: Grant
    Filed: December 15, 2003
    Date of Patent: April 4, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Nobutaka Takeuchi, Hajime Oyama, Hiromitsu Takagaki, Takayuki Koike
  • Publication number: 20060008281
    Abstract: A developer container includes a developer container configured to contain a developer including a toner and a carrier, a developer delivering mechanism configured to deliver the developer toward an image bearing member of an image forming apparatus, and a detecting mechanism configured to detect deterioration of the developer based on a predetermined characteristic of the developer.
    Type: Application
    Filed: June 20, 2005
    Publication date: January 12, 2006
    Inventors: Junichi Matsumoto, Nobuo Iwata, Satoshi Muramatsu, Nobutaka Takeuchi, Takayuki Koike, Eriko Maruyama
  • Publication number: 20050265759
    Abstract: An image forming apparatus, using a developer including toner particles and carrier particles, includes a developing unit, a cleaning unit, and a conveying unit. The developing unit contains the developer and develops an electrostatic latent image formed on an image carrying member as a toner image with the toner particles. The cleaning unit contains the developer and mixes the developer with the toner particles collected from the image carrying member after transferring the toner image. The conveying unit conveys a mixture of the collected toner particles and the developer from the cleaning unit to the developing unit.
    Type: Application
    Filed: May 17, 2005
    Publication date: December 1, 2005
    Inventors: Nobutaka Takeuchi, Nobuo Iwata, Satoshi Muramatsu, Junichi Matsumoto, Takayuki Koike, Eriko Maruyama
  • Patent number: 6946229
    Abstract: A color toner which gives a suitable image gloss and has an excellent color reproducibility, which has sufficient anti-offset properties even when a release oil is not coated on a fixing roller or is coated in only a small amount, and which has excellent transfer properties, durability, and charge stability relative to humidity is disclosed. Also, an image-forming apparatus using the color toner and a toner container filled with the color toner are disclosed. The color toner comprises a continuous phase of a resin containing a urea-modified polyester resin; and a modified resin dispersed in the continuous phase, wherein the modified resin contains a release polymer portion containing a release polymer; and a modified portion containing a plurality of vinyl monomer units, the modified portion having an average ester group concentration of 8% by weight to 30% by weight.
    Type: Grant
    Filed: August 26, 2003
    Date of Patent: September 20, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Masanori Suzuki, Takuya Saito, Hiroshi Yamashita, Yohichiroh Watanabe, Takeshi Takada, Tsunemi Sugiyama, Satoshi Mochizuki, Yasuaki Iwamoto, Takayuki Koike
  • Publication number: 20050163537
    Abstract: An image forming apparatus of the present invention includes a developing unit for developing a latent image formed on an image carrier with a two-ingredient type developer, i.e., a toner and carrier mixture. A toner replenishing device replenishes toner stored in a toner storing portion to the developing unit. A carrier storing portion, storing a carrier therein, is constructed independently of the toner storing portion. The carrier is fed from the carrier storing portion to the developing unit by a toner conveying force available with the toner replenishing device.
    Type: Application
    Filed: December 22, 2004
    Publication date: July 28, 2005
    Inventors: Satoshi Muramatsu, Nobuo Iwata, Nobutaka Takeuchi, Junichi Matsumoto, Takayuki Koike, Eriko Maruyama
  • Publication number: 20050095037
    Abstract: A developing apparatus which uses a two-component developer consisting of a toner and carrier. The ratio between the amount of the developer M1 which is drawn onto a developing slave and refluxes while being regulated by a doctor blade, and the amount of the developer (drawn amount) M2 which passes through the doctor blade is M1/M2<10. The toner is a negatively-charged toner. In a charge amount distribution the number of toners of ?1 fc/10 ?m or more is 20% or less of the total number of toners.
    Type: Application
    Filed: September 15, 2004
    Publication date: May 5, 2005
    Inventors: Takayuki Koike, Nobutaka Takeuchi, Nobuo Iwata, Satoshi Muramatsu, Jyunichi Matsumoto
  • Patent number: 6887636
    Abstract: A toner for a two-component developer comprising the toner and carrier particles, the developer being used for an oilless fixing-type image forming apparatus comprising a developer carrier rotatable at a linear speed of 360-1,680 mm/sec, and a developer adjusting member extending in a lateral direction parallel to the rotational axis of the developer carrier and disposed adjacent to the developer carrier to define a gap therebetween of 0.3-1.0 mm, said image forming apparatus being operated so that the amount of the developer conveyed by the developer carrier and passing through the gap per 1 second is 5.0-25.0 g per 1 cm of the lateral width of the gap, the toner comprising a wax dispersed therein and the toner having a coefficient of dynamic friction in the range of 0.18-0.45.
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: May 3, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroaki Matsuda, Kazuyuki Yazaki, Takayuki Koike, Koji Suzuki, Tadashi Kasai, Yutaka Takahashi, Mitsuo Aoki, Naohito Shimota, Akihiro Itoh
  • Publication number: 20050089347
    Abstract: A developer container includes a developer storage unit made of a flexible sheet material for storing developer, and a cap unit from which the developer is discharged. The developer storage unit includes a holding member that holds a folded state when the developer storage unit is folded.
    Type: Application
    Filed: September 17, 2004
    Publication date: April 28, 2005
    Inventors: Satoshi Muramatsu, Nobuo Iwata, Junichi Matsumoto, Nobutaka Takeuchi, Takayuki Koike
  • Publication number: 20040265015
    Abstract: A developing device includes a developer carrier that carries a developer and a developer restricting member that restricts a layer thickness of the developer on the developer carrier. The developer carrier carries the developer in such a manner that a thickness Tup of a layer of the developer when the layer passes through the developer restricting member and a gap Gd between the developer restricting member and the developer carrier satisfy an inequality 7<Tup/Gd<20.
    Type: Application
    Filed: June 25, 2004
    Publication date: December 30, 2004
    Inventors: Takayuki Koike, Hajime Oyama, Hiromitsu Takagaki, Nobutaka Takeuchi
  • Publication number: 20040265014
    Abstract: A developing unit includes a developer containing unit that contains developer, a developer carrier that has a moving surface, and carries the developer, a magnetic force generator that attracts the developer onto the moving surface by a magnetic force generated from a plurality of magnets, and a restricting member that restricts a layer thickness of the developer. The magnets includes a restricting magnet arranged closest to the restricting member and has a restricting magnetic pole of which a first surface toward the moving surface and a second surface toward an upstream adjacent magnet that is arranged so as to be adjacent to an upstream side of the developer carrier in a direction of movement of the moving surface and has an upstream adjacent magnetic pole form a ridged corner portion, and the ridged corner portion is chamfered.
    Type: Application
    Filed: June 22, 2004
    Publication date: December 30, 2004
    Inventors: Nobutaka Takeuchi, Hajime Oyama, Hiromitsu Takagaki, Takayuki Koike
  • Publication number: 20040190947
    Abstract: A developing device of the present invention includes stationary layer angle setting means. Assume that a developer layer, staying at a position upstream of a metering member in a direction in which a developer carrier conveys a developer, consists of a stationary layer in which the developer is not replaced and a flowing layer in which it is replaced, that an angle between, as seen from the axis of the developer carrier, the upstream edge portion, in the above direction, of the end portion of the metering member, which faces the developer carrier, and a position where the end of the stationary layer upstream of, but remote from the edge portion, is located is &thgr;d, and that an angle between, as seen from the above axis, the edge portion and a position where a magnetic pole is positioned just upstream of a doctor pole in the above direction is &thgr;1. Then, the angle &thgr;d lies in a preselected range relative to the angle &thgr;1.
    Type: Application
    Filed: December 15, 2003
    Publication date: September 30, 2004
    Inventors: Nobutaka Takeuchi, Hajime Oyama, Hiromitsu Takagaki, Takayuki Koike
  • Publication number: 20040121256
    Abstract: A color toner which gives a suitable image gloss and has an excellent color reproducibility, which has sufficient anti-offset properties even when a release oil is not coated on a fixing roller or is coated in only a small amount, and which has excellent transfer properties, durability, and charge stability relative to humidity is disclosed. Also, an image-forming apparatus using the color toner and a toner container filled with the color toner are disclosed. The color toner comprises a continuous phase of a resin containing a urea-modified polyester resin; and a modified resin dispersed in the continuous phase, wherein the modified resin contains a release polymer portion containing a release polymer; and a modified portion containing a plurality of vinyl monomer units, the modified portion having an average ester group concentration of 8% by weight to 30% by weight.
    Type: Application
    Filed: August 26, 2003
    Publication date: June 24, 2004
    Inventors: Masanori Suzuki, Takuya Saito, Hiroshi Yamashita, Yohichiroh Watanabe, Takeshi Takada, Tsunemi Sugiyama, Satoshi Mochizuki, Yasuaki Iwamoto, Takayuki Koike
  • Publication number: 20030180643
    Abstract: A developer for developing an electrostatic latent image, including a carrier which includes core particles, and a surface layer surrounding each of the core particles and containing an acrylic resin binder; and a toner which includes toner particles and an external additive of inorganic or organic fine particles present on each of the toner particles. Each of the toner particles comprises a colorant, a matrix of a first resin, and a plurality of domains of a second resin dispersed in the matrix and containing a wax. The first resin is substantially free of tetrahydrofuran insoluble matters and has a weight average molecular weight of 3,000 to 90,000.
    Type: Application
    Filed: March 20, 2003
    Publication date: September 25, 2003
    Inventors: Kohsuke Suzuki, Satoshi Mochizuki, Tomio Kondou, Masahide Yamashita, Tomomi Tamura, Takayuki Koike
  • Publication number: 20030104297
    Abstract: A toner for a two-component developer comprising the toner and carrier particles, the developer being used for an oilless fixing-type image forming apparatus comprising a developer carrier rotatable at a linear speed of 360-1,680 mm/sec, and a developer adjusting member extending in a lateral direction parallel to the rotational axis of the developer carrier and disposed adjacent to the developer carrier to define a gap therebetween of 0.3-1.0 mm, said image forming apparatus being operated so that the amount of the developer conveyed by the developer carrier and passing through the gap per 1 second is 5.0-25.0 g per 1 cm of the lateral width of the gap, the toner comprising a wax dispersed therein and the toner having a coefficient of dynamic friction in the range of 0.18-0.45.
    Type: Application
    Filed: May 31, 2002
    Publication date: June 5, 2003
    Inventors: Hiroaki Matsuda, Kazuyuki Yazaki, Takayuki Koike, Koji Suzuki, Tadashi Kasai, Yutaka Takahashi, Mitsuo Aoki, Naohito Shimota, Akihiro Itoh
  • Patent number: 6324942
    Abstract: An engine crankshaft (1) made by forging, that has larger counter weights (8) without increasing a manufacturing cost. Engaging two dies with each other performs the forging. Each counter weight (8) has a plurality of inclinations (&thgr;1, &thgr;2) to facilitate removal of the dies from the crankshaft after the forging process is complete. The inclinations are reduced as they are apart from a die mating surface (P). The maximum thickness (T) of each counter weight (8) is not enlarged so that interference between the counter weights and neighboring parts is avoided. No machining is required after the forging process.
    Type: Grant
    Filed: January 4, 2000
    Date of Patent: December 4, 2001
    Assignee: Isuzu Motors Limited
    Inventors: Takayuki Koike, Toshihiro Matsui