Patents by Inventor Yu Wakabayashi

Yu Wakabayashi 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: 11128024
    Abstract: A combiner-divider includes a first impedance converter disposed between the first port and the second port, a second impedance converter disposed between the first port and the third port, and an isolation unit disposed between the second port and the third port. The isolation unit includes a balun formed of a first semi-rigid cable and a second semi-rigid cable, and terminating resistors. Each line length of the first impedance converter, the second impedance converter, and the third impedance converter corresponds to ¼ wavelength at a center frequency. A relationship of each impedance Ri of the second port and the third port, an impedance Ro of the first port, and each impedance W of the first impedance converter and the second impedance converters is expressed by W=(2×Ri×Ro)1/2.
    Type: Grant
    Filed: January 30, 2017
    Date of Patent: September 21, 2021
    Assignee: HITACHI KOKUSAI ELECTRIC INC.
    Inventors: Yusaburo Goto, Keiichi Sakamaki, Yu Wakabayashi
  • Publication number: 20210221636
    Abstract: A sheet conveying device includes a pair of rollers including a first roller and a second roller to hold a sheet conveyed between the first and second rollers; a biasing member to bias the first roller toward the second roller; a biasing force changer to change a biasing force of the biasing member; control circuitry to, when a predetermined changing condition is met, cause the changer to change the biasing force and cause the rollers to convey the sheet; an operation detector to detect a changing operation of the changer; and a notification device to notify an abnormality of the changing operation when the operation detector detects the abnormality. When the operation detector detects the abnormality, the control circuitry performs sheet conveyance control to cause the rollers to convey the sheet without causing the changer to change the biasing force, regardless of whether the predetermined changing condition is met.
    Type: Application
    Filed: January 11, 2021
    Publication date: July 22, 2021
    Applicant: Ricoh Company, Ltd.
    Inventors: Yu WAKABAYASHI, Kazuya YAMAMOTO, Yasuhide FUKUSHIMA, Yuuki SHIGA, Ryohhei OHYA
  • Publication number: 20210214176
    Abstract: A sheet conveying device includes a pair of rollers, a biasing member, a guide member, a biasing support, and a biasing force changer. The pair of rollers includes a first roller and a second roller disposed in contact with the first roller. The pair of rollers is configured to hold a sheet between the first roller and the second roller. The biasing member is configured to bias the first roller toward the second roller. The biasing support is configured to support the biasing member and has a guide target member configured to slide along the guide member to move the biasing support. The biasing force changer is configured to change a biasing force of the biasing member along with movement of the biasing. support. The guide target member has a portion projecting into a sheet conveyance passage through which the sheet is conveyed by the pair of rollers.
    Type: Application
    Filed: January 6, 2021
    Publication date: July 15, 2021
    Applicant: Ricoh Company, Ltd.
    Inventors: Yasuhide FUKUSHIMA, Yu WAKABAYASHI, Yuuki SHIGA, Kazuya YAMAMOTO, Ryohhei OHYA
  • Publication number: 20190379100
    Abstract: A combiner-divider includes a first impedance converter disposed between the first port and the second port, a second impedance converter disposed between the first port and the third port, and an isolation unit disposed between the second port and the third port. The isolation unit includes a balun formed of a first semi-rigid cable and a second semi-rigid cable, and terminating resistors. Each line length of the first impedance converter, the second impedance converter, and the third impedance converter corresponds to ¼ wavelength at a center frequency. A relationship of each impedance Ri of the second port and the third port, an impedance Ro of the first port, and each impedance W of the first impedance converter and the second impedance converters is expressed by W=(2×Ri×Ro)½.
    Type: Application
    Filed: January 30, 2017
    Publication date: December 12, 2019
    Inventors: Yusaburo GOTO, Keiichi SAKAMAKI, Yu WAKABAYASHI
  • Patent number: 10144599
    Abstract: A sheet feeding device, which is included in an image forming apparatus, includes a sheet container to accommodate a recording medium, a sheet feeding body to press a surface of the recording medium in the sheet container and feed the recording medium in a sheet conveying direction, a pair of sheet position regulators to regulate a position of the recording medium in a sheet width direction perpendicular to the sheet conveying direction, and a load applier to contact the surface of the recording medium and apply a load to the recording medium at the surface. The recording medium is brought to move toward one of the pair of sheet position regulators while the recording medium is being fed. A lower face position in a standby state of the sheet feeding body is lower than a lower face position in a standby state of the load applier.
    Type: Grant
    Filed: December 21, 2016
    Date of Patent: December 4, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yu Wakabayashi, Kaoru Shoji, Masashi Sato, Shohei Shinkawa, Tetsutaro Oishi, Rie Ohtsuka
  • Patent number: 10114323
    Abstract: A sheet size detector to detect a sheet size of a recording medium includes a movable member to move in a sheet size detection direction to a position corresponding to the sheet size, a magnetic flux detector including a coil disposed on a board face parallel to the sheet size detection direction to generate a magnetic flux in a direction perpendicular to the board face, and a target to oppose the board face and including a material to affect the magnetic flux. The target is different in configuration in the sheet size detection direction to change the magnetic flux in the direction perpendicular to the board face as the movable member moves. The magnetic flux detector outputs a signal corresponding to changes in magnetic flux in the direction perpendicular to the board face, and the signal corresponds to the position of the movable member.
    Type: Grant
    Filed: March 9, 2015
    Date of Patent: October 30, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsuro Hirota, Yu Wakabayashi, Shintaroh Yamada, Shun Kobayashi
  • Patent number: 9902578
    Abstract: A sheet containing device, which is included in a sheet feeder and an image forming apparatus, includes a first sheet container, a second sheet container disposed adjacent to the first sheet container, a transfer unit to transfer a bundle of sheets contained in the second sheet container to the first sheet container, a pair of side fences including a first side fence and a second side fence to regulate a position of the bundle of sheets in a width direction of the bundle of sheets loaded on the first sheet container, and a pressing unit mounted on the first side fence and pressing the bundle of sheets loaded on the first sheet container against the second side fence.
    Type: Grant
    Filed: April 27, 2016
    Date of Patent: February 27, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yu Wakabayashi, Ryuta Kaneda, Shohei Shinkawa
  • Publication number: 20170185025
    Abstract: A sheet feeding device, which is included in an image forming apparatus, includes a sheet container to accommodate a recording medium, a sheet feeding body to press a surface of the recording medium in the sheet container and feed the recording medium in a sheet conveying direction, a pair of sheet position regulators to regulate a position of the recording medium in a sheet width direction perpendicular to the sheet conveying direction, and a load applier to contact the surface of the recording medium and apply a load to the recording medium at the surface. The recording medium is brought to move toward one of the pair of sheet position regulators while the recording medium is being fed. A lower face position in a standby state of the sheet feeding body is lower than a lower face position in a standby state of the load applier.
    Type: Application
    Filed: December 21, 2016
    Publication date: June 29, 2017
    Applicant: Ricoh Company, Ltd.
    Inventors: YU WAKABAYASHI, Kaoru Shoji, Masashi Sato, Shohei Shinkawa, Tetsutaro Oishi, Rie Ohtsuka
  • Publication number: 20160334747
    Abstract: A sheet containing device, which is included in a sheet feeder and an image forming apparatus, includes a first sheet container, a second sheet container disposed adjacent to the first sheet container, a transfer unit to transfer a bundle of sheets contained in the second sheet container to the first sheet container, a pair of side fences including a first side fence and a second side fence to regulate a position of the bundle of sheets in a width direction of the bundle of sheets loaded on the first sheet container, and a pressing unit mounted on the first side fence and pressing the bundle of sheets loaded on the first sheet container against the second side fence.
    Type: Application
    Filed: April 27, 2016
    Publication date: November 17, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Yu WAKABAYASHI, Ryuta Kaneda, Shohei Shinkawa
  • Publication number: 20150268028
    Abstract: A sheet size detector to detect a sheet size of a recording medium includes a movable member to move in a sheet size detection direction to a position corresponding to the sheet size, a magnetic flux detector including a coil disposed on a board face parallel to the sheet size detection direction to generate a magnetic flux in a direction perpendicular to the board face, and a target to oppose the board face and including a material to affect the magnetic flux. The target is different in configuration in the sheet size detection direction to change the magnetic flux in the direction perpendicular to the board face as the movable member moves. The magnetic flux detector outputs a signal corresponding to changes in magnetic flux in the direction perpendicular to the board face, and the signal corresponds to the position of the movable member.
    Type: Application
    Filed: March 9, 2015
    Publication date: September 24, 2015
    Applicant: Ricoh Company, Ltd.
    Inventors: Tetsuro HIROTA, Yu WAKABAYASHI, Shintaroh YAMADA, Shun KOBAYASHI
  • Patent number: 8511668
    Abstract: A sheet feeding device includes a sheet carrying unit and an attraction separation and conveyance device. The sheet carrying unit is configured to carry thereon a sheet stack. The attraction separation and conveyance device is configured to electrostatically attract the uppermost sheet of the sheet stack and separate and convey the uppermost sheet from the sheet stack, and is placed between the upstream end and the central position in a sheet conveying direction of the sheet stack located at a sheet carrying position and having a minimum sheet size compatible with the sheet feeding device.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: August 20, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshikuni Ishikawa, Yu Wakabayashi, Toshiaki Takahashi, Manabu Nonaka
  • Patent number: 8474811
    Abstract: A sheet feeding device includes a sheet carrying unit, an attraction separation device electrostatically attracting and separating an uppermost sheet from a sheet stack and including multiple rollers, an endless dielectric belt stretched over the multiple rollers, and an elastic member provided inside a loop of the belt to cause the endless dielectric belt to contact the uppermost sheet, a sheet conveying device, and a lifting and lowering device. The lifting and lowering device lifts the sheet stack to a lift position at which the uppermost sheet contacts with the attraction separation device, and the attraction separation device stands by for a predetermined time to attract the uppermost sheet and starts to convey the uppermost sheet after the predetermined time elapses in a state in which the sheet stack remains at the lift position.
    Type: Grant
    Filed: April 10, 2012
    Date of Patent: July 2, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshiaki Takahashi, Yoshikuni Ishikawa, Yu Wakabayashi, Manabu Nonaka
  • Patent number: 8439347
    Abstract: A sheet conveying device includes an attractive separation unit and a contacting and separating device. The attractive separation unit includes an attraction belt arranged to face the upper surface of a sheet stack, two rollers that stretch the attraction belt taut, with the upstream-side roller in the sheet conveying direction supported to be movable in substantially upward and downward directions within a predetermined range with respect to the upper surface of the sheet stack, and a charging device which charges a surface of the attraction belt. The contacting and separating device swings the attractive separation unit to make the attraction belt come into contact with and separate from the sheet stack, with a fulcrum of the swing of the attractive separation unit set to a position upstream in the sheet conveying direction of the upstream-side roller in the sheet conveying direction.
    Type: Grant
    Filed: January 28, 2011
    Date of Patent: May 14, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshikuni Ishikawa, Manabu Nonaka, Yu Wakabayashi, Aki Ikeda
  • Patent number: 8428480
    Abstract: A fixing device includes a fixing member, a pressing member, a temperature detector, and a heater. The pressing member contacts an outer circumferential surface of the fixing member to form a fixing nip between the fixing member and the pressing member through which a recording medium bearing a toner image passes. The heater heats the fixing member to a predetermined temperature based on a detection result provided by the temperature detector. A circumferential distance A between the temperature detector and the heater along a circumference of the fixing member is defined by the following formula: A?v×(T1+T2) where v is a circumferential velocity of the fixing member rotating in a predetermined direction of rotation, T1 is a response time of the temperature detector, and T2 is a response time of the heater.
    Type: Grant
    Filed: October 22, 2010
    Date of Patent: April 23, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohta Takenaka, Kazunori Bannai, Yu Wakabayashi, Toshihiro Shimada, Hidehiko Fujiwara
  • Publication number: 20120193861
    Abstract: A sheet feeding device includes a sheet carrying unit, an attraction separation device electrostatically attracting and separating an uppermost sheet from a sheet stack and including multiple rollers, an endless dielectric belt stretched over the multiple rollers, and an elastic member provided inside a loop of the belt to cause the endless dielectric belt to contact the uppermost sheet, a sheet conveying device, and a lifting and lowering device. The lifting and lowering device lifts the sheet stack to a lift position at which the uppermost sheet contacts with the attraction separation device, and the attraction separation device stands by for a predetermined time to attract the uppermost sheet and starts to convey the uppermost sheet after the predetermined time elapses in a state in which the sheet stack remains at the lift position.
    Type: Application
    Filed: April 10, 2012
    Publication date: August 2, 2012
    Inventors: Toshiaki Takahashi, Yoshikuni Ishikawa, Yu Wakabayashi, Manabu Nonaka
  • Patent number: 8177217
    Abstract: A sheet feeding device includes a sheet carrying unit, an attraction separation device electrostatically attracting and separating an uppermost sheet from a sheet stack and including multiple rollers, an endless dielectric belt stretched over the multiple rollers, and an elastic member provided inside a loop of the belt to cause the endless dielectric belt to contact the uppermost sheet, a sheet conveying device, and a lifting and lowering device. The lifting and lowering device lifts the sheet stack to a lift position at which the uppermost sheet contacts with the attraction separation device, and the attraction separation device stands by for a predetermined time to attract the uppermost sheet and starts to convey the uppermost sheet after the predetermined time elapses in a state in which the sheet stack remains at the lift position.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: May 15, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshiaki Takahashi, Yoshikuni Ishikawa, Yu Wakabayashi, Manabu Nonaka
  • Publication number: 20110204557
    Abstract: A sheet conveying device includes an attractive separation unit and a contacting and separating device. The attractive separation unit includes an attraction belt arranged to face the upper surface of a sheet stack, two rollers that stretch the attraction belt taut, with the upstream-side roller in the sheet conveying direction supported to be movable in substantially upward and downward directions within a predetermined range with respect to the upper surface of the sheet stack, and a charging device which charges a surface of the attraction belt. The contacting and separating device swings the attractive separation unit to make the attraction belt come into contact with and separate from the sheet stack, with a fulcrum of the swing of the attractive separation unit set to a position upstream in the sheet conveying direction of the upstream-side roller in the sheet conveying direction.
    Type: Application
    Filed: January 28, 2011
    Publication date: August 25, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Yoshikuni Ishikawa, Manabu Nonaka, Yu Wakabayashi, Aki Ikeda
  • Publication number: 20110127711
    Abstract: A sheet feeding device includes a sheet carrying unit, an attraction separation device electrostatically attracting and separating an uppermost sheet from a sheet stack and including multiple rollers, an endless dielectric belt stretched over the multiple rollers, and an elastic member provided inside a loop of the belt to cause the endless dielectric belt to contact the uppermost sheet, a sheet conveying device, and a lifting and lowering device. The lifting and lowering device lifts the sheet stack to a lift position at which the uppermost sheet contacts with the attraction separation device, and the attraction separation device stands by for a predetermined time to attract the uppermost sheet and starts to convey the uppermost sheet after the predetermined time elapses in a state in which the sheet stack remains at the lift position.
    Type: Application
    Filed: November 23, 2010
    Publication date: June 2, 2011
    Inventors: Toshiaki Takahashi, Yoshikuni Ishikawa, Yu Wakabayashi, Manabu Nonaka
  • Publication number: 20110121506
    Abstract: A sheet feeding device includes a sheet carrying unit and an attraction separation and conveyance device. The sheet carrying unit is configured to carry thereon a sheet stack. The attraction separation and conveyance device is configured to electrostatically attract the uppermost sheet of the sheet stack and separate and convey the uppermost sheet from the sheet stack, and is placed between the upstream end and the central position in a sheet conveying direction of the sheet stack located at a sheet carrying position and having a minimum sheet size compatible with the sheet feeding device.
    Type: Application
    Filed: November 22, 2010
    Publication date: May 26, 2011
    Inventors: Yoshikuni ISHIKAWA, Yu WAKABAYASHI, Toshiaki TAKAHASHI, Manabu NONAKA
  • Publication number: 20110116822
    Abstract: A fixing device includes a fixing member, a pressing member, a temperature detector, and a heater. The pressing member contacts an outer circumferential surface of the fixing member to form a fixing nip between the fixing member and the pressing member through which a recording medium bearing a toner image passes. The heater heats the fixing member to a predetermined temperature based on a detection result provided by the temperature detector. A circumferential distance A between the temperature detector and the heater along a circumference of the fixing member is defined by the following formula: A?v×(T1+T2) where v is a circumferential velocity of the fixing member rotating in a predetermined direction of rotation, T1 is a response time of the temperature detector, and T2 is a response time of the heater.
    Type: Application
    Filed: October 22, 2010
    Publication date: May 19, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Kohta Takenaka, Kazunori Bannai, Yu Wakabayashi, Toshihiro Shimada, Hidehiko Fujiwara