Patents by Inventor Keiji Okano

Keiji Okano 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: 7289756
    Abstract: A developer regulating member abutting against a developer carrying member carrying a mono-component developer to regulate the layer thickness of the developer on the developer carrying member has a supported portion supported by a support member, and an abutting portion abutting against the developer carrying member, the surface roughness parameters of this abutting portion satisfying the following expressions (1) to (5): 0.30?Sm?0.170??(1) Rpk?2.0??(2) Rp?5.0??(3) 0.10?Rvk×(100?Mr2)/100?1.30??(4) Rpk<Rvk,??(5) where Sm is a mean spacing [mm] of profile irregularities prescribed by JIS-B0601-1994, Rp is a maximum profile peak height [?m] prescribed by ISO4287-1997, Rpk is an initial wear height [?m] prescribed by DIN4776, Rvk is an oil retaining depth [?m] prescribed by DIN4776, and Mr2 is a profile bearing length ratio 2 [%] prescribed by DIN4776.
    Type: Grant
    Filed: October 24, 2005
    Date of Patent: October 30, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideaki Hasegawa, Keiji Okano
  • Publication number: 20070065185
    Abstract: A developer regulating member abutting against a developer carrying member carrying a mono-component developer to regulate the layer thickness of the developer on the developer carrying member has a supported portion supported by a support member, and an abutting portion abutting against the developer carrying member, the surface roughness parameters of this abutting portion satisfying the following expressions (1) to (5): 0.30?Sm?0.170??(1) Rpk?2.0??(2) Rp?5.0??(3) 0.10?Rvk×(100?Mr2)/100?1.30??(4) Rpk<Rvk??(5), where Sm is a mean spacing [mm] of profile irregularities prescribed by JIS-B0601-1994, Rp is a maximum profile peak height [?m] prescribed by ISO4287-1997, Rpk is an initial wear height [?m] prescribed by DIN4776, Rvk is an oil retaining depth [?m] prescribed by DIN4776, and Mr2 is a profile bearing length ratio 2 [%] prescribed by DIN4776.
    Type: Application
    Filed: October 24, 2005
    Publication date: March 22, 2007
    Applicant: Canon Kabushiki Kaisha
    Inventors: Hideaki Hasegawa, Keiji Okano
  • Patent number: 7194215
    Abstract: A memory medium is provided to a cartridge detachably mountable to an image forming apparatus. Into the memory medium, as information for performing charge control, information on the amount of usage of an image-bearing member and information on a charging alternating voltage (a threshold value for selection control of a charging peak-to-peak voltage Vpp) are written. The image forming apparatus includes a charging-bias power-supply circuit, on its body side, including AC oscillation output circuit capable of outputting two or more species of alternating peak-to-peak voltages and an AC detector for detecting an alternating current passing through the image-bearing member. Charge control is performed on the basis of a detected value detected by the AC detector and memory information for the cartridge, whereby good charge control space saving, and cost reduction of the power-supply circuit are compatibly realized.
    Type: Grant
    Filed: August 16, 2005
    Date of Patent: March 20, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiji Okano, Satoshi Sunahara, Satoru Motohashi
  • Patent number: 7035560
    Abstract: A memory medium is provided to a cartridge detachably mountable to an image forming apparatus. Into the memory medium, as information for performing charge control, information on the amount of usage of an image-bearing member and information on a charging alternating voltage (a threshold value for selection control of a charging peak-to-peak voltage Vpp) are written. The image forming apparatus includes a charging-bias power-supply circuit, on its body side, including AC oscillation output circuit capable of outputting two or more species of alternating peak-to-peak voltages and an AC detector for detecting an alternating current passing through the image-bearing member. Charge control is performed on the basis of a detected value detected by the AC detector and memory information for the cartridge, whereby good charge control space saving, and cost reduction of the power-supply circuit are compatibly realized.
    Type: Grant
    Filed: April 3, 2003
    Date of Patent: April 25, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiji Okano, Satoshi Sunahara, Satoru Motohashi
  • Publication number: 20050271406
    Abstract: A memory medium is provided to a cartridge detachably mountable to an image forming apparatus. Into the memory medium, as information for performing charge control, information on the amount of usage of an image-bearing member and information on a charging alternating voltage (a threshold value for selection control of a charging peak-to-peak voltage Vpp) are written. The image forming apparatus includes a charging-bias power-supply circuit, on its body side, including AC oscillation output circuit capable of outputting two or more species of alternating peak-to-peak voltages and an AC detector for detecting an alternating current passing through the image-bearing member. Charge control is performed on the basis of a detected value detected by the AC detector and memory information for the cartridge, whereby good charge control space saving, and cost reduction of the power-supply circuit are compatibly realized.
    Type: Application
    Filed: August 16, 2005
    Publication date: December 8, 2005
    Applicant: Canon Kabushiki Kaisha
    Inventors: Keiji Okano, Satoshi Sunahara, Satoru Motohashi
  • Patent number: 6898401
    Abstract: A charging system includes a rotatable member to be charged, and a rotatable charging member provided with electroconductive particles thereon and forming a nip part with the member to be charged and disposed in the nip part to charge the member to be charged. When the diameter of the member to be charged is defined as LD (mm) and the diameter of the charging member is defined as LC (mm), LD?25 and LD×LC?350. As a result,, in the charging system, and a process cartridge and an image-forming apparatus including such a charging system, an image-bearing member can be made small in diameter.
    Type: Grant
    Filed: April 18, 2003
    Date of Patent: May 24, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiji Okano, Masahiro Yoshida
  • Patent number: 6882806
    Abstract: A charging apparatus includes a charging member, contactably provided to a member to be charged, for charging the member to be charged; a voltage application device for applying alternating voltages having different peak-to-peak voltages to the charging member; and a determination device for determining a peak-to-peak voltage to be applied to the charging member with respect to a second area of the member to be charged, on the basis of a peak-to-peak voltage corresponding to a minimum current which is not less than a predetermined current of alternating currents through the member to be charged when the alternating voltages having the different peak-to-peak voltages are applied to the charging member with respect to a first area of the member to be charged.
    Type: Grant
    Filed: April 3, 2003
    Date of Patent: April 19, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Satoshi Sunahara, Keiji Okano, Satoru Motohashi
  • Patent number: 6829447
    Abstract: A developing apparatus includes developer carrying member for carrying a developer; wherein the developer carrying member is supplied with a developing voltage comprising a superimposed DC voltage component and AC voltage component to develop an electrostatic latent image formed on an image bearing member; switching means for switching an image density of a developed image on the image bearing member; wherein when the image density of the developed image is made higher than a predetermined image density in accordance with an output of the switching means, the frequency of the AC voltage component is made higher than a predetermined frequency.
    Type: Grant
    Filed: December 10, 2001
    Date of Patent: December 7, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventor: Keiji Okano
  • Patent number: 6741824
    Abstract: An image forming apparatus has an image bearing member; and a charging member forming a nip with the image bearing member to charge the image bearing member. Conductive particles are provided in the nip and a time factor &agr; represented by a following equation satisfies a condition &agr;>15: &agr;=2&pgr;·k·Nc·(W/Vc)/(&rgr;·Cd·Z) Z=−0.5·1n(&pgr;·k·Nc)−1n({square root over (&bgr;)}·D/2) (&bgr;=1.
    Type: Grant
    Filed: April 18, 2003
    Date of Patent: May 25, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaki Ojima, Noboru Kashimura, Keiji Okano, Junichi Kato
  • Publication number: 20040022558
    Abstract: A charging system is provided with a rotatable member to be charged, and a rotatable charging member provided with electroconductive particles thereon and forming a nip part with the member to be charged and disposed in the nip part to charge the member to be charged, wherein when the diameter of the member to be charged is defined as LD (mm) and the diameter of the charging member is defined as LC (mm), LD≦25 and LD×LC≧350 are satisfied. Thereby, in the charging system, a process cartridge and an image forming apparatus, an image bearing member can be made small in diameter.
    Type: Application
    Filed: April 18, 2003
    Publication date: February 5, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Keiji Okano, Masahiro Yoshida
  • Patent number: 6686942
    Abstract: When a user changes a density adjusting value (developing contrast), and even when variations in the usage state of process characteristics (of the photosensitive body and the developing device) of the cartridge change, the amount of recording agent consumed can be suppressed to be low, and a sharp line image can be recorded. An image forming apparatus of this invention includes an edge detecting portion for detecting an edge of image data, an image data correcting portion for correcting image data inside the edge so as to decrease its density, a laser driving circuit for forming an electrostatic latent image on a photosensitive body, and a correction value determining table for acquiring an instruction value for giving an instruction to correct a density contrast, wherein a correction condition for image data changes in accordance with an instruction value.
    Type: Grant
    Filed: November 21, 2002
    Date of Patent: February 3, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiji Okano, Gaku Konishi, Akira Domon
  • Publication number: 20030215253
    Abstract: A memory medium is provided to a cartridge detachably mountable to an image forming apparatus. Into the memory medium, as information for performing charge control, information on an amount of usage of an image-bearing member and information on a charging alternating voltage (a threshold value for selection control of charging peak-to-peak voltage Vpp) are written. The image forming apparatus includes a charging bias power supply circuit, on its body side, including AC oscillation output means capable of outputting two or more species of alternating peak-to-peak voltages and AC detection means for detecting an alternating current through the image-bearing member. Charge control is performed on the basis of a detected value detected by the AC detection means and memory information for the cartridge, whereby good charge control and space saving and cost reduction of the power supply circuit are compatibly realized.
    Type: Application
    Filed: April 3, 2003
    Publication date: November 20, 2003
    Applicant: Canon Kabushiki Kaisha
    Inventors: Keiji Okano, Satoshi Sunahara, Satoru Motohashi
  • Publication number: 20030198485
    Abstract: An image forming apparatus according to the present invention includes an image bearing member, and a charging member for forming a nip with the image bearing member thereby charging the image bearing member, wherein conductive particles are provided in the nip, wherein a time factor a represented by a following equation satisfies a condition &agr;>15:
    Type: Application
    Filed: April 18, 2003
    Publication date: October 23, 2003
    Applicant: Canon Kabushiki Kaisha
    Inventors: Masaki Ojima, Noboru Kashimura, Keiji Okano, Junichi Kato
  • Publication number: 20030090559
    Abstract: When a user changes a density adjusting value (developing contrast), and even variations and usage state of the process characteristics (photosensitive body and developing) of the cartridge change, the amount of recording agent consumed can be suppressed low, and a sharp line image can be recorded. An image forming apparatus of this invention includes an edge detecting portion for detecting an edge of image data, an image data correcting portion for correcting image data inside the edge so as to decrease its density, a laser driving circuit for forming an electrostatic latent image on a photosensitive body, and a correction value determining table for acquiring an instruction value for giving an instruction to correct a density contrast, wherein a correction condition for image data changes in accordance with an instruction value.
    Type: Application
    Filed: November 21, 2002
    Publication date: May 15, 2003
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Keiji Okano, Gaku Konishi, Akira Domon
  • Patent number: 6559875
    Abstract: An image forming apparatus which includes an image bearing body and a light beam scanner for exposing the image bearing body, which is charged, based on an image signal and forming an electrostatic latent image on the image bearing body. A rise time or a fall time of a light beam emitted from the light beam scanner is controlled when a pixel density of the electrostatic latent image is switched.
    Type: Grant
    Filed: June 13, 2001
    Date of Patent: May 6, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiji Okano, Shinichi Tsukida, Akira Domon
  • Patent number: 6532030
    Abstract: When a user changes a density adjusting value (developing contrast), and even when variations in the usage state of process characteristics (of the photosensitive body and the developing device) of the cartridge change, the amount of recording agent consumed can be suppressed to be low, and a sharp line image can be recorded. An image forming apparatus of this invention includes an edge detecting portion for detecting an edge of image data, an image data correcting portion for correcting image data inside the edge so as to decrease its density, a laser driving circuit for forming an electrostatic latent image on a photosensitive body, and a correction value determining table for acquiring an instruction value for giving an instruction to correct a density contrast, wherein a correction condition for image data changes in accordance with an instruction value.
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: March 11, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiji Okano, Gaku Konishi, Akira Domon
  • Publication number: 20020164174
    Abstract: A developing apparatus includes developer carrying member for carrying a developer; wherein the developer carrying member is supplied with a developing voltage comprising a superimposed DC voltage component and AC voltage component to develop an electrostatic latent image formed on an image bearing member; switching means for switching an image density of a developed image on the image bearing member; wherein when the image density of the developed image is made higher than a predetermined image density in accordance with an output of the switching means, the frequency of the AC voltage component is made higher than a predetermined frequency.
    Type: Application
    Filed: December 10, 2001
    Publication date: November 7, 2002
    Inventor: Keiji Okano
  • Publication number: 20020119381
    Abstract: A photosensitive member which can prevent occurrence of a streak image due to wear of a surface of the photosensitive member while preventing occurrence of image-flow is provided, and an average particle diameter of a scraped particle obtained from a surface of the photosensitive member by the rubbing of a cleaning member is 9.0 &mgr;m or less.
    Type: Application
    Filed: October 28, 1999
    Publication date: August 29, 2002
    Inventors: SATORU MOTOHASHI, KEIJI OKANO, MASANOBU SAITO, GAKU KONISHI, YASUSHI SHIMIZU, HIROSHI SATO, AKIRA DOMON
  • Publication number: 20020097314
    Abstract: When a user changes a density adjusting value (developing contrast), and even variations and usage state of the process characteristics (photosensitive body and developing) of the cartridge change, the amount of recording agent consumed can be suppressed low, and a sharp line image can be recorded. An image forming apparatus of this invention includes an edge detecting portion for detecting an edge of image data, an image data correcting portion for correcting image data inside the edge so as to decrease its density, a laser driving circuit for forming an electrostatic latent image on a photosensitive body, and a correction value determining table for acquiring an instruction value for giving an instruction to correct a density contrast, wherein a correction condition for image data changes in accordance with an instruction value.
    Type: Application
    Filed: November 9, 2001
    Publication date: July 25, 2002
    Inventors: Keiji Okano, Gaku Konishi, Akira Domon
  • Patent number: 6370348
    Abstract: A developing apparatus includes a developer containing portion containing a developer having a weight average particle diameter of not more than 7 &mgr;m, a developer bearing member for bearing a developer, and an agitating member that agitates the developer contained in the developer containing portion. The agitating member is intermittently driven with respect to rotation of a developing sleeve. The agitating member is driven to rotate for one page every time the image forming apparatus performs a predetermined number of printing operations. A rod member having a crank-like shape may be used as the agitating member and both of the end portions serve as the center of rotation. By controlling the drive of the agitating member, it is possible to effectively adjust the supply of toner to the developing sleeve and prevent the density lowering phenomena caused due to inflow of a large amount of the new toner presented at the rear of the developing container.
    Type: Grant
    Filed: May 12, 2000
    Date of Patent: April 9, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keiji Okano, Koichi Suwa, Masahiro Yoshida, Hideki Matsumoto