Patents by Inventor Kaori Hemmi

Kaori Hemmi 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).

  • Publication number: 20210088948
    Abstract: An image forming apparatus includes a plurality of temperature-influence members, a first-point temperature acquisition unit, a second-point temperature estimation unit, and a controller. The plurality of temperature-influence members have influence on a temperature of a recording medium on which an image is formed. The first-point temperature acquisition unit is configured to detect or estimate a temperature of the recording medium at a first point. The second-point temperature estimation unit is configured to estimate a temperature of the recording medium at a second point, based on a detection result of at least one of a temperature of the recording medium at a point different from the second point and a temperature of a member or atmosphere. The controller is configured to control the plurality of temperature-influence members, based on an acquisition result from the first-point temperature acquisition unit and an estimation result from the second-point temperature estimation unit.
    Type: Application
    Filed: September 24, 2020
    Publication date: March 25, 2021
    Applicants: Ricoh Company, Ltd., TOKYO INSTITUTE OF TECHNOLOGY
    Inventors: Kaori HEMMI, Koichi KATO, Kimiharu YAMAZAKI, Kazuyoshi FUSHINOBU, Shunsuke KAWASAKI, Shinichi KURAMOTO
  • Patent number: 10488774
    Abstract: An image forming apparatus including a developing device and a fixing device is provided. The fixing device includes a fixing rotator having a fixing surface, an opposing rotator opposing the fixing rotator to form a nip portion therebetween, and a fixing surface reformer having an abutting layer to abut the fixing surface. The abutting layer contains abrasive grains having an average grain size of 2.0-6.5 ?m on a surface which abuts the fixing surface. The toner comprises a crystalline polyester resin and exhibits G? (storage elastic modulus) of 1.0×107 Pa or lower at 70° C. in a temperature rising in a viscoelasticity measurement, G? of 1.0×107 Pa or higher at 70° C. in a temperature falling in the viscoelasticity measurement, and an endothermic peak indicating an amount of heat absorption of from 2.0 to 8.0 J/g, derived from the crystalline polyester resin, in a first temperature rising in DSC.
    Type: Grant
    Filed: March 1, 2019
    Date of Patent: November 26, 2019
    Assignee: Ricoh Company, Ltd.
    Inventors: Daisuke Inoue, Takahiro Honda, Masami Okamoto, Kenta Kashiwagi, Kaori Hemmi, Yoshihisa Hara
  • Patent number: 10481530
    Abstract: A separation member that is used to separate a conveyance object from two rotation members, the conveyance object having been sent out from a nip that is formed by the two rotation members that are in contact with one another, the separation member includes a wavy part directed toward the nip and inclined from a normal to a center line of the two rotation members at a predetermined angle. The wavy part covers a contact zone where the conveyance object can come into contact with the separation member along a conveyance direction and along a width direction of the conveyance object, and the wavy part has a plurality of depressions parallel to each other and extending in a direction inclined from the conveyance direction and inclined from the width direction, at least two of the depressions overlapping along the conveyance direction.
    Type: Grant
    Filed: June 18, 2018
    Date of Patent: November 19, 2019
    Assignee: RICOH COMPANY, LTD.
    Inventors: Seiji Saitoh, Keisuke Kubota, Masami Okamoto, Kenji Nozawa, Fumihiro Hirose, Kensuke Yamaji, Shuutaroh Yuasa, Yuuki Kikushima, Kaori Hemmi, Yuuta Kanda
  • Publication number: 20190271927
    Abstract: An image forming apparatus including a developing device and a fixing device is provided. The fixing device includes a fixing rotator having a fixing surface, an opposing rotator opposing the fixing rotator to form a nip portion therebetween, and a fixing surface reformer having an abutting layer to abut the fixing surface. The abutting layer contains abrasive grains having an average grain size of 2.0-6.5 ?m on a surface which abuts the fixing surface. The toner comprises a crystalline polyester resin and exhibits G? (storage elastic modulus) of 1.0×107 Pa or lower at 70° C. in a temperature rising in a viscoelasticity measurement, G? of 1.0×107 Pa or higher at 70° C. in a temperature falling in the viscoelasticity measurement, and an endothermic peak indicating an amount of heat absorption of from 2.0 to 8.0 J/g, derived from the crystalline polyester resin, in a first temperature rising in DSC.
    Type: Application
    Filed: March 1, 2019
    Publication date: September 5, 2019
    Inventors: Daisuke Inoue, Takahiro Honda, Masami Okamoto, Kenta Kashiwagi, Kaori Hemmi, Yoshihisa Hara
  • Patent number: 10114322
    Abstract: A fixing device includes a fixing belt that is rotatable and a pressure rotator that is pressed against the fixing belt to form a fixing nip therebetween. A polishing roller separably contacts the fixing belt and slides over an outer circumferential surface of the fixing belt while the polishing roller is pressed against the fixing belt. At least one support supports and stretches the fixing belt. A polishing aid, which is disposed opposite the polishing roller via the fixing belt, supports and stretches the fixing belt. The polishing roller is disposed opposite the polishing aid via the fixing belt to form a polishing nip between the polishing roller and the fixing belt while the polishing roller is pressed against the fixing belt. The polishing roller changes a rotation locus of the fixing belt along at least a part of a circumferential face of the polishing roller.
    Type: Grant
    Filed: July 24, 2017
    Date of Patent: October 30, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Kenichi Hasegawa, Takashi Fujita, Hiroyuki Shimada, Kaori Hemmi
  • Publication number: 20180299809
    Abstract: A separation member that is used to separate a conveyance object from two rotation members, the conveyance object having been sent out from a nip that is formed by the two rotation members that are in contact with one another, the separation member includes a wavy part directed toward the nip and inclined from a normal to a center line of the two rotation members at a predetermined angle. The wavy part covers a contact zone where the conveyance object can come into contact with the separation member along a conveyance direction and along a width direction of the conveyance object, and the wavy part has a plurality of depressions parallel to each other and extending in a direction inclined from the conveyance direction and inclined from the width direction, at least two of the depressions overlapping along the conveyance direction.
    Type: Application
    Filed: June 18, 2018
    Publication date: October 18, 2018
    Inventors: Seiji Saitoh, Keisuke Kubota, Masami Okamoto, Kenji Nozawa, Fumihiro Hirose, Kensuke Yamaji, Shuutaroh Yuasa, Yuuki Kikushima, Kaori Hemmi, Yuuta Kanda
  • Patent number: 10012936
    Abstract: A fixing device includes a fixing belt that is endless and rotatable in a rotation direction and a nip former stretching the fixing belt and including an elastic layer as a surface layer. A pressure rotator presses against the nip former via the fixing belt to form a fixing nip between the fixing belt and the pressure rotator, through which a recording medium is conveyed. A presser is disposed downstream from an exit of the fixing nip in a recording medium conveyance direction. The presser brings the fixing belt into contact with the pressure rotator.
    Type: Grant
    Filed: March 2, 2017
    Date of Patent: July 3, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Kensuke Yamaji, Keisuke Kubota, Seiji Saitoh, Masami Okamoto, Fumihiro Hirose, Shuutaroh Yuasa, Kenji Nozawa, Kaori Hemmi, Jun Ogino, Yuuta Kanda
  • Patent number: 9939761
    Abstract: A fixing device includes an endless fixing belt stretched taut across a first roller and a second roller and rotatable in a predetermined direction of rotation. A pressure rotator is pressed against the first roller via the fixing belt to form a fixing nip between the pressure rotator and the fixing belt, through which a recording medium is conveyed. A separation aid, disposed downstream from the fixing nip in the direction of rotation of the fixing belt to separate the recording medium from the fixing belt, includes a contact face contacting an inner circumferential surface of the fixing belt and a bulge disposed at a center of the contact face in a longitudinal direction of the separation aid. The bulge projects toward the inner circumferential surface of the fixing belt relative to each lateral end of the contact face in the longitudinal direction of the separation aid.
    Type: Grant
    Filed: October 27, 2015
    Date of Patent: April 10, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Kenji Nozawa, Masahiko Satoh, Masami Okamoto, Keisuke Kubota, Yuuki Kikushima, Shuutaroh Yuasa, Fumihiro Hirose, Kensuke Yamaji, Kaori Hemmi
  • Publication number: 20180059598
    Abstract: A fixing device includes a fixing belt that is rotatable and a pressure rotator that is pressed against the fixing belt to form a fixing nip therebetween. A polishing roller separably contacts the fixing belt and slides over an outer circumferential surface of the fixing belt while the polishing roller is pressed against the fixing belt. At least one support supports and stretches the fixing belt. A polishing aid, which is disposed opposite the polishing roller via the fixing belt, supports and stretches the fixing belt. The polishing roller is disposed opposite the polishing aid via the fixing belt to form a polishing nip between the polishing roller and the fixing belt while the polishing roller is pressed against the fixing belt. The polishing roller changes a rotation locus of the fixing belt along at least a part of a circumferential face of the polishing roller.
    Type: Application
    Filed: July 24, 2017
    Publication date: March 1, 2018
    Inventors: Kenichi HASEGAWA, Takashi FUJITA, Hiroyuki SHIMADA, Kaori HEMMI
  • Patent number: 9811034
    Abstract: An image forming apparatus includes an image forming device that forms an image on a sheet, a fixing device including a fixing member that fixes the image formed on the sheet and a polishing device that polishes a surface of the fixing member, and circuitry that determines whether an interruption required operation is to be performed, at a time while image formation is being performed by the image forming device to execute an image forming job, or at a time after image formation is executed for one job and before image formation is to be executed for a subsequent job, controls the image forming device to stop image formation to perform the interruption required operation, based on a determination indicating that the interruption required operation is to be performed, and controls the polishing device to polish the surface of the fixing member concurrently with the interruption required operation.
    Type: Grant
    Filed: August 2, 2016
    Date of Patent: November 7, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Kawabe, Kaori Hemmi, Keisuke Kubota
  • Publication number: 20170269524
    Abstract: A fixing device includes a fixing belt that is endless and rotatable in a rotation direction and a nip former stretching the fixing belt and including an elastic layer as a surface layer. A pressure rotator presses against the nip former via the fixing belt to form a fixing nip between the fixing belt and the pressure rotator, through which a recording medium is conveyed. A presser is disposed downstream from an exit of the fixing nip in a recording medium conveyance direction. The presser brings the fixing belt into contact with the pressure rotator.
    Type: Application
    Filed: March 2, 2017
    Publication date: September 21, 2017
    Inventors: Kensuke YAMAJI, Keisuke KUBOTA, Seiji SAITOH, Masami OKAMOTO, Fumihiro HIROSE, Shuutaroh YUASA, Kenji NOZAWA, Kaori HEMMI, Jun OGINO, Yuuta KANDA
  • Patent number: 9733600
    Abstract: A fixing device includes a fixing belt looped over a first roller and a second roller and rotatable in a predetermined direction of rotation and a pressure rotator to press against the first roller via the fixing belt to form a fixing nip between the fixing belt and the pressure rotator. A separation aid, disposed downstream from the fixing nip in the direction of rotation of the fixing belt, contacts an inner circumferential surface of the fixing belt to decrease a radius of curvature of the fixing belt. A polishing roller, disposed downstream from the separation aid and upstream from the second roller in the direction of rotation of the fixing belt, contacts an outer circumferential surface of the fixing belt. An opposed roller, disposed opposite the polishing roller via the fixing belt, forms a polishing nip between the polishing roller and the fixing belt.
    Type: Grant
    Filed: March 14, 2016
    Date of Patent: August 15, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Kenji Nozawa, Masami Okamoto, Yuuki Kikushima, Keisuke Kubota, Shuutaroh Yuasa, Kaori Hemmi
  • Publication number: 20170052492
    Abstract: An image forming apparatus includes an image forming device that forms an image on a sheet, a fixing device including a fixing member that fixes the image formed on the sheet and a polishing device that polishes a surface of the fixing member, and circuitry that determines whether an interruption required operation is to be performed, at a time while image formation is being performed by the image forming device to execute an image forming job, or at a time after image formation is executed for one job and before image formation is to be executed for a subsequent job, controls the image forming device to stop image formation to perform the interruption required operation, based on a determination indicating that the interruption required operation is to be performed, and controls the polishing device to polish the surface of the fixing member concurrently with the interruption required operation.
    Type: Application
    Filed: August 2, 2016
    Publication date: February 23, 2017
    Inventors: Hiroshi KAWABE, Kaori HEMMI, Keisuke KUBOTA
  • Patent number: 9519249
    Abstract: A fixing device includes a cylindrical heat roller; a plurality of heaters disposed inside the heat roller, extending along a longitudinal axis of the heat roller; and a heat adjuster, disposed among the plurality of heaters, to adjust heat from one to another of the plurality of heaters. An image forming apparatus includes an image forming section to form an image on a recording medium; and the fixing device as described above, to fix the image onto the recording medium.
    Type: Grant
    Filed: December 14, 2015
    Date of Patent: December 13, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Fumihiro Hirose, Masami Okamoto, Kenji Nozawa, Yuuki Kikushima, Kensuke Yamaji, Keisuke Kubota, Shuutaroh Yuasa, Kaori Hemmi
  • Publication number: 20160306304
    Abstract: A fixing device includes a heater, a fixing rotator, a pressure rotator, a slider, and a controller. The fixing rotator is heated by the heater. The pressure rotator presses at least a portion of the fixing rotator and forms a nip between the pressure rotator and the fixing rotator. The fixing rotator fixes an unfixed toner image on a recording material in the nip. The slider slides over a surface of the fixing rotator. The controller causes the slider to perform a first sliding operation for a predetermined time after a predetermined condition is satisfied. The controller causes the slider to perform a second sliding operation for a time equal to or less than the predetermined time at earlier timing than when the predetermined condition is satisfied, in addition to the first sliding operation.
    Type: Application
    Filed: April 13, 2016
    Publication date: October 20, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Kaori Hemmi, Masami Okamoto, Keisuke Kubota, Yuuki Kikushima, Shuutaroh Yuasa, Fumihiro Hirose, Kensuke Yamaji, Kenji Nozawa
  • Publication number: 20160209789
    Abstract: A sheet separation device includes a separator disposed to contact one face of a sheet conveyed through a nip between conveyors contacting each other. The separator configured to separate from surfaces of the conveyors the sheet conveyed through the nip. The separator includes a conveyance face and a slanted face. The conveyance face is configured to contact and convey the sheet conveyed through the nip. The slanted face is disposed closer to the nip than the conveyance face and inclined with respect to the conveyance face toward one conveyor of the conveyors at a same side as the one face of the sheet.
    Type: Application
    Filed: January 18, 2016
    Publication date: July 21, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Kenji NOZAWA, Masami OKAMOTO, Yuuki KIKUSHIMA, Fumihiro HIROSE, Kensuke YAMAJI, Keisuke KUBOTA, Shuutaroh YUASA, Kaori HEMMI, Seiji SAITOH
  • Patent number: 9389560
    Abstract: A fixing device includes a guide disposed downstream from a fixing nip formed between a fixing rotator and a pressure rotator, through which a recording medium is conveyed. A pressure rotator side separator, disposed downstream from the fixing nip in a recording medium conveyance direction, includes an opposed tip disposed opposite an outer circumferential surface of the pressure rotator and a separation-conveyance face that separates the recording medium from the pressure rotator. The opposed tip and the separation-conveyance face define a hypothetical circle having a curvature not smaller than 1/20 that intersects a guide face of the guide at an intersection at which a hypothetical tangent is tangent to the hypothetical circle. The hypothetical tangent and the guide face define a downstream intersection angle that is downstream from the hypothetical tangent in the recording medium conveyance direction and is greater than 90 degrees.
    Type: Grant
    Filed: August 19, 2015
    Date of Patent: July 12, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Fumihiro Hirose, Masami Okamoto, Kenji Nozawa, Yuuki Kikushima, Kensuke Yamaji, Keisuke Kubota, Shuutaroh Yuasa, Kaori Hemmi
  • Publication number: 20160170350
    Abstract: A fixing device includes a cylindrical heat roller; a plurality of heaters disposed inside the heat roller, extending along a longitudinal axis of the heat roller; and a heat adjuster, disposed among the plurality of heaters, to adjust heat from one to another of the plurality of heaters. An image forming apparatus includes an image forming section to form an image on a recording medium; and the fixing device as described above, to fix the image onto the recording medium.
    Type: Application
    Filed: December 14, 2015
    Publication date: June 16, 2016
    Inventors: Fumihiro HIROSE, Masami OKAMOTO, Kenji NOZAWA, Yuuki KIKUSHIMA, Kensuke YAMAJI, Keisuke KUBOTA, Shuutaroh YUASA, Kaori HEMMI
  • Publication number: 20160170348
    Abstract: A fixing device includes a cylindrical heat roller; a plurality of heaters disposed inside the heat roller, extending along a longitudinal axis of the heat roller; and a heat adjuster, disposed among the plurality of heaters, to adjust heat from one to another of the plurality of heaters. An image forming apparatus includes an image forming section to form an image on a recording medium; and the fixing device as described above, to fix the image onto the recording medium.
    Type: Application
    Filed: December 1, 2015
    Publication date: June 16, 2016
    Inventors: Fumihiro HIROSE, Masami Okamoto, Kenji Nozawa, Yuuki Kikushima, Kensuke Yamaji, Keisuke Kubota, Shuutaroh Yuasa, Kaori Hemmi
  • Publication number: 20160139549
    Abstract: A fixing device includes an endless fixing belt stretched taut across a first roller and a second roller and rotatable in a predetermined direction of rotation. A pressure rotator is pressed against the first roller via the fixing belt to form a fixing nip between the pressure rotator and the fixing belt, through which a recording medium is conveyed. A separation aid, disposed downstream from the fixing nip in the direction of rotation of the fixing belt to separate the recording medium from the fixing belt, includes a contact face contacting an inner circumferential surface of the fixing belt and a bulge disposed at a center of the contact face in a longitudinal direction of the separation aid. The bulge projects toward the inner circumferential surface of the fixing belt relative to each lateral end of the contact face in the longitudinal direction of the separation aid.
    Type: Application
    Filed: October 27, 2015
    Publication date: May 19, 2016
    Inventors: Kenji NOZAWA, Masahiko SATOH, Masami OKAMOTO, Keisuke KUBOTA, Yuuki KlKUSHIMA, Shuutaroh YUASA, Fumihiro HIROSE, Kensuke YAMAJI, Kaori HEMMI