Patents by Inventor Masaaki Yoshikawa

Masaaki Yoshikawa 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: 10935911
    Abstract: A fixing device includes an endless belt rotatable in a predetermined direction of rotation and a nip formation assembly disposed opposite an inner circumferential surface of the endless belt. An opposed rotary body is pressed against the nip formation assembly via the endless belt to form a fixing nip between the endless belt and the opposed rotary body through which a recording medium bearing a toner image is conveyed. A belt holder contacts and supports each lateral end of the endless belt in an axial direction thereof. The belt holder is isolated from the opposed rotary body with a first interval interposed therebetween in the axial direction of the endless belt.
    Type: Grant
    Filed: October 30, 2017
    Date of Patent: March 2, 2021
    Assignee: Ricoh Company, Ltd.
    Inventors: Teppei Kawata, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Kensuke Yamaji, Takamasa Hase, Toshihiko Shimokawa, Shuutaroh Yuasa, Takuya Seshita, Takeshi Uchitani, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki
  • Patent number: 10001735
    Abstract: A fixing device may include an endless fixing member; a heater inside the fixing member; and a nip forming unit configured to form a nip through which a recording sheet is conveyed, the nip forming unit including a supporting member and a contact member supported by the supporting member, the supporting member including at least one contact surface and the contact member including a plurality of protrusions protruding towards the supporting member such that two or more of the plurality of protrusions are configured to contact one of the at least one contact surface of the supporting member, each of the plurality of protrusions having a height associated there with such that the height of the plurality of protrusions increases in a direction from ends of the contact member towards a center of the contact member.
    Type: Grant
    Filed: December 20, 2016
    Date of Patent: June 19, 2018
    Assignee: Ricoh Company, Limited
    Inventors: Takahiro Imada, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Yuji Arai, Naoki Iwaya, Tetsuo Tokuda, Hiromasa Takagi, Yoshiki Yamaguchi, Ippei Fujimoto, Takuya Seshita, Yutaka Ikebuchi, Arinobu Yoshiura, Toshihiko Shimokawa, Hajime Gotoh
  • Patent number: 9983526
    Abstract: A fixing device includes a heat source; a fixing member looped into a generally cylindrical shape to rotate in a circumferential direction thereof and partially heated by the heat source and to heat a surface of a recording medium bearing an unfixed toner image to fix the unfixed toner image thereon in a fixing process; a rotary pressing member disposed facing the fixing member to form a nip therebetween, through which the recording medium is transported in a transport direction; and a rotation driver to rotate one of the fixing member and the pressing member. In a case in which the fixing member is halted for a reason other than the fixing process while power of the fixing device is on, electric power is not supplied to the heat source and the fixing member is rotated by a predetermined amount or more after the fixing member is halted.
    Type: Grant
    Filed: June 9, 2017
    Date of Patent: May 29, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Uchitani, Masahiko Satoh, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Takamasa Hase, Shuutaroh Yuasa, Masaaki Yoshikawa, Hiromasa Takagi, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Takuya Seshita, Hiroshi Yoshinaga, Kazuya Saito, Shinichi Namekata, Takayuki Seki, Yuji Arai, Ryuuichi Mimbu, Yoshiki Yamaguchi, Shuntaroh Tamaki, Yutaka Ikebuchi
  • Patent number: 9971289
    Abstract: An image forming apparatus includes a fixing device. The fixing device includes a rotatable endless fixing member, a nip forming member arranged inside the fixing member, a pressing member in contact with the nip forming member via the fixing member, and a heating source configured to heat the fixing member. When an abnormality occurs in at least one of the fixing device and other devices included in the image forming apparatus, a rotation of the fixing member is stopped prior to stopping a rotation driving of a discharging unit and, after stopping, the fixing member is controlled to rotate.
    Type: Grant
    Filed: May 23, 2017
    Date of Patent: May 15, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Takamasa Hase, Masahiko Satoh, Shinichi Namekata, Kenji Ishii, Takeshi Uchitani, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Kensuke Yamaji, Masaaki Yoshikawa, Hiroshi Yoshinaga, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Akira Suzuki
  • Patent number: 9927748
    Abstract: A fixing device includes: a rotatable endless fixing belt; a nip forming member arranged inside the fixing belt; a facing rotating body that abuts the nip forming member via the fixing belt to form a nip portion with the fixing belt; a heat source that directly heats up the fixing belt at a portion other than the nip portion; and a supporting member that supports the nip forming member. The fixing device conveys a recording medium carrying an unfixed image to the nip portion to fix the unfixed image to the recording medium, and the supporting member includes a rising portion extending in an abutting direction of the facing rotating body against the fixing belt and having a tip close to an inner circumferential surface of the fixing belt, and is set to have a section modulus of 200 mm3 or higher.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: March 27, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hiroshi Yoshinaga, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Teppei Kawata, Toshihiko Shimokawa, Arinobu Yoshiura, Takamasa Hase, Takeshi Uchitani, Shuutaroh Yuasa, Kensuke Yamaji
  • Publication number: 20180046121
    Abstract: A fixing device includes an endless belt rotatable in a predetermined direction of rotation and a nip formation assembly disposed opposite an inner circumferential surface of the endless belt. An opposed rotary body is pressed against the nip formation assembly via the endless belt to form a fixing nip between the endless belt and the opposed rotary body through which a recording medium bearing a toner image is conveyed. A belt holder contacts and supports each lateral end of the endless belt in an axial direction thereof. The belt holder is isolated from the opposed rotary body with a first interval interposed therebetween in the axial direction of the endless belt.
    Type: Application
    Filed: October 30, 2017
    Publication date: February 15, 2018
    Inventors: Teppei KAWATA, Masahiko SATOH, Masaaki YOSHIKAWA, Kenji ISHll, Hiroshi YOSHINAGA, Tadashi OGAWA, Takahiro IMADA, Hiromasa TAKAGI, Kazuya SAITO, Naoki IWAYA, Kensuke YAMAJI, Takamasa HASE, Toshihiko SHIMOKAWA, Shuutaroh YUASA, Takuya SESHITA, Takeshi UCHITANI, Arinobu YOSHIURA, Hajime GOTOH, Akira SUZUKI
  • Patent number: 9811031
    Abstract: A fixing device includes an endless belt rotatable in a predetermined direction of rotation and a nip formation assembly disposed opposite an inner circumferential surface of the endless belt. An opposed rotary body is pressed against the nip formation assembly via the endless belt to form a fixing nip between the endless belt and the opposed rotary body through which a recording medium bearing a toner image is conveyed. A belt holder contacts and supports each lateral end of the endless belt in an axial direction thereof. The belt holder is isolated from the opposed rotary body with a first interval interposed therebetween in the axial direction of the endless belt.
    Type: Grant
    Filed: September 8, 2015
    Date of Patent: November 7, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Teppei Kawata, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Kensuke Yamaji, Takamasa Hase, Toshihiko Shimokawa, Shuutaroh Yuasa, Takuya Seshita, Takeshi Uchitani, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki
  • Publication number: 20170293245
    Abstract: A fixing device for fixing an image on a recording medium includes an endless fixing rotary member which is formed into a loop and comes into contact with the image on the recording medium, an opposed rotary member which is in contact with the fixing rotary member, a nip forming member provided inside the loop of the fixing rotary member to be in contact with the opposed rotary member via the fixing rotary member to form a nip portion to which the recording medium is fed in a feeding direction, a support member which supports the nip forming member, and a heating source which heats the fixing rotary member. The nip forming member includes a downstream portion extending downstream in the feeding direction from a center of the nip portion and an upstream portion extending upstream in the feeding direction from the center and longer than the downstream portion.
    Type: Application
    Filed: June 27, 2017
    Publication date: October 12, 2017
    Inventors: Teppei Kawata, Masahiko Satoh, Kenji Ishii, Masaaki Yoshikawa, Hiroshi Yoshinaga, Takeshi Uchitani, Tadashi Ogawa, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Takamasa Hase, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Arinobu Yoshiura, Kensuke Yamaji, Akira Suzuki
  • Publication number: 20170277091
    Abstract: A fixing device includes a heat source; a fixing member looped into a generally cylindrical shape to rotate in a circumferential direction thereof and partially heated by the heat source and to heat a surface of a recording medium bearing an unfixed toner image to fix the unfixed toner image thereon in a fixing process; a rotary pressing member disposed facing the fixing member to form a nip therebetween, through which the recording medium is transported in a transport direction; and a rotation driver to rotate one of the fixing member and the pressing member. In a case in which the fixing member is halted for a reason other than the fixing process while power of the fixing device is on, electric power is not supplied to the heat source and the fixing member is rotated by a predetermined amount or more after the fixing member is halted.
    Type: Application
    Filed: June 9, 2017
    Publication date: September 28, 2017
    Inventors: Takeshi UCHITANI, Masahiko SATOH, Kenji ISHII, Tadashi OGAWA, Teppei KAWATA, Arinobu YOSHIURA, Toshihiko SHIMOKAWA, Kensuke YAMAJI, Takamasa HASE, Shuutaroh YUASA, Masaaki YOSHIKAWA, Hiromasa TAKAGI, Takahiro IMADA, Hajime GOTOH, Akira SUZUKI, Takuya SESHITA, Hiroshi YOSHINAGA, Kazuya SAITO, Shinichi NAMEKATA, Takayuki SEKI, Yuji ARAI, Ryuuichi MIMBU, Yoshiki YAMAGUCHI, Shuntaroh TAMAKI, Yutaka IKEBUCHI
  • Publication number: 20170255150
    Abstract: An image forming apparatus includes a fixing device. The fixing device includes a rotatable endless fixing member, a nip forming member arranged inside the fixing member, a pressing member in contact with the nip forming member via the fixing member, and a heating source configured to heat the fixing member. When an abnormality occurs in at least one of the fixing device and other devices included in the image forming apparatus, a rotation of the fixing member is stopped prior to stopping a rotation driving of a discharging unit and, after stopping, the fixing member is controlled to rotate.
    Type: Application
    Filed: May 23, 2017
    Publication date: September 7, 2017
    Inventors: Takamasa HASE, Masahiko SATOH, Shinichi NAMEKATA, Kenji ISHll, Takeshi UCHITANI, Tadashi OGAWA, Teppei KAWATA, Arinobu YOSHIURA, Kazuya SAITO, Toshihiko SHIMOKAWA, Shuutaroh YUASA, Kensuke YAMAJI, Masaaki YOSHIKAWA, Hiroshi YOSHINAGA, Hiromasa TAKAGI, Naoki IWAYA, Takuya SESHITA, Takahiro IMADA, Hajime GOTOH, Akira SUZUKI
  • Patent number: 9727011
    Abstract: An image forming apparatus includes a first heater disposed opposite and heating at least a center of a fixing belt in an axial direction thereof and a second heater disposed opposite and heating at least a lateral end of the fixing belt in the axial direction thereof. A power supply supplies power to the first heater and the second heater. A controller that controls the power supply includes a calculator to calculate an elapsed time elapsed after at least one of the first heater and the second heater starts heating the fixing belt. The controller controls the power supply to supply power to the first heater and the second heater such that a power density of the second heater is greater than a power density of the first heater when the elapsed time calculated by the calculator is smaller than a predetermined time.
    Type: Grant
    Filed: July 22, 2016
    Date of Patent: August 8, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Yutaka Ikebuchi, Hiroshi Yoshinaga, Takayuki Seki, Yuji Arai, Ryuuichi Mimbu, Shuntaro Tamaki, Kazuya Saito, Shuutaroh Yuasa, Toshihiko Shimokawa, Masaaki Yoshikawa, Toshiharu Hachisuka
  • Patent number: 9727008
    Abstract: A fixing device for fixing an image on a recording medium includes an endless fixing rotary member which is formed into a loop and comes into contact with the image on the recording medium, an opposed rotary member which is in contact with the fixing rotary member, a nip forming member provided inside the loop of the fixing rotary member to be in contact with the opposed rotary member via the fixing rotary member to form a nip portion to which the recording medium is fed in a feeding direction, a support member which supports the nip forming member, and a heating source which heats the fixing rotary member. The nip forming member includes a downstream portion extending downstream in the feeding direction from a center of the nip portion and an upstream portion extending upstream in the feeding direction from the center and longer than the downstream portion.
    Type: Grant
    Filed: December 17, 2012
    Date of Patent: August 8, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Teppei Kawata, Masahiko Satoh, Kenji Ishii, Masaaki Yoshikawa, Hiroshi Yoshinaga, Takeshi Uchitani, Tadashi Ogawa, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Takamasa Hase, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Arinobu Yoshiura, Kensuke Yamaji, Akira Suzuki
  • Patent number: 9715203
    Abstract: A fixing device includes a heat source; a fixing member looped into a generally cylindrical shape to rotate in a circumferential direction thereof and partially heated by the heat source and to heat a surface of a recording medium bearing an unfixed toner image to fix the unfixed toner image thereon in a fixing process; a rotary pressing member disposed facing the fixing member to form a nip therebetween, through which the recording medium is transported in a transport direction; and a rotation driver to rotate one of the fixing member and the pressing member. In a case in which the fixing member is halted for a reason other than the fixing process while power of the fixing device is on, electric power is not supplied to the heat source and the fixing member is rotated by a predetermined amount or more after the fixing member is halted.
    Type: Grant
    Filed: December 11, 2015
    Date of Patent: July 25, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Uchitani, Masahiko Satoh, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Takamasa Hase, Shuutaroh Yuasa, Masaaki Yoshikawa, Hiromasa Takagi, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Takuya Seshita, Hiroshi Yoshinaga, Kazuya Saito, Shinichi Namekata, Takayuki Seki, Yuji Arai, Ryuuichi Mimbu, Yoshiki Yamaguchi, Shuntaroh Tamaki, Yutaka Ikebuchi
  • Patent number: 9690243
    Abstract: An image forming apparatus includes a fixing device. The fixing device includes a rotatable endless fixing member, a nip forming member arranged inside the fixing member, a pressing member in contact with the nip forming member via the fixing member, and a heating source configured to heat the fixing member. When an abnormality occurs in at least one of the fixing device and other devices included in the image forming apparatus, a rotation of the fixing member is stopped prior to stopping a rotation driving of a discharging unit and, after stopping, the fixing member is controlled to rotate.
    Type: Grant
    Filed: October 30, 2015
    Date of Patent: June 27, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Takamasa Hase, Masahiko Satoh, Shinichi Namekata, Kenji Ishii, Takeshi Uchitani, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Kensuke Yamaji, Masaaki Yoshikawa, Hiroshi Yoshinaga, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Akira Suzuki
  • Publication number: 20170102652
    Abstract: According to an embodiments, a fixing device includes: an endless fixing member; a heating unit that is provided inside an inner peripheral surface of the fixing member; and a nip forming unit that comes into press-contact with a rotationally driven pressing member with the fixing member interposed therebetween to form a nip. The nip forming unit has a shape in which a center of a contact surface protrudes toward the pressing member compared to both ends. The nip forming unit has a protruding amount at a center toward the pressing member compared to both ends of the nip forming unit in no-load state is set to be less than a bent amount of the nip forming unit when the nip forming unit comes into press-contact with the pressing member with the fixing member interposed therebetween.
    Type: Application
    Filed: December 20, 2016
    Publication date: April 13, 2017
    Applicant: Ricoh Company, Ltd.
    Inventors: Takahiro IMADA, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Yuji Arai, Naoki Iwaya, Tetsuo Tokuda, Hiromasa Takagi, Yoshiki Yamaguchi, Ippei Fujimoto, Takuya Seshita, Yutaka Ikebuchi, Arinobu Yoshiura, Toshihiko Shimokawa, Hajime Gotoh
  • Patent number: 9564262
    Abstract: A superconducting magnetic field generating device includes: a superconductor including an outer superconductor formed with a high temperature superconducting material in a cylindrical shape and generating a trapped magnetic field, and an inner superconductor formed with a high temperature superconducting material in a cylindrical shape and coaxially disposed with the outer superconductor on the inner circumferential side; and a cooling device cooling the outer and inner superconductors to a temperature equal to or lower than the superconducting transition temperature, wherein the inner superconductor is formed so that a ratio (Jc?1/Jcz1) of a critical current density (Jc?1) of the inner superconductor in the circumferential direction to a critical current density (Jcz1) of the inner superconductor in the axial direction is closer to 1 than a ratio (Jc?2/Jcz2) of the critical current density (Jc?2) in the circumferential direction to a critical current density (Jcz2) of the outer superconductor of the outer s
    Type: Grant
    Filed: June 18, 2015
    Date of Patent: February 7, 2017
    Assignee: AISIN SEIKI KABUSHIKI KAISHA
    Inventors: Yoshitaka Ito, Yousuke Yanagi, Masaaki Yoshikawa
  • Patent number: 9557692
    Abstract: A fixing device may include an endless fixing member; a heating unit that is provided inside an inner peripheral surface of the fixing member; and a nip forming unit that comes into press-contact with a rotationally driven pressing member with the fixing member interposed therebetween to form a nip. The nip forming unit has a shape in which a center of a contact surface protrudes toward the pressing member compared to both ends. The nip forming unit has a protruding amount at a center toward the pressing member compared to both ends of the nip forming unit in no-load state is set to be less than a bent amount of the nip forming unit when the nip forming unit comes into press-contact with the pressing member with the fixing member interposed therebetween.
    Type: Grant
    Filed: September 11, 2015
    Date of Patent: January 31, 2017
    Assignee: Ricoh Company, Limited
    Inventors: Takahiro Imada, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Yuji Arai, Naoki Iwaya, Tetsuo Tokuda, Hiromasa Takagi, Yoshiki Yamaguchi, Ippei Fujimoto, Takuya Seshita, Yutaka Ikebuchi, Arinobu Yoshiura, Toshihiko Shimokawa, Hajime Gotoh
  • Patent number: 9535380
    Abstract: A fixing device includes a fixing rotator, a first heat generator and a second heat generator that heat the fixing rotator, and a support disposed inside the fixing rotator. A reflector, interposed between the support and each of the first heat generator and the second heat generator, reflects light radiated from the first heat generator and the second heat generator toward the fixing rotator. The reflector includes a body mounted on the support and a shield portion projecting from the body toward the first heat generator and the second heat generator to shield the fixing rotator from the first heat generator and the second heat generator. An electric circuit is connected to the first heat generator and the second heat generator. A heat generation restrainer is provided in the electric circuit to restrict heat generation in the electric circuit.
    Type: Grant
    Filed: May 15, 2014
    Date of Patent: January 3, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshihiko Shimokawa, Yutaka Ikebuchi, Hiroshi Yoshinaga, Takayuki Seki, Yuji Arai, Ryuuichi Mimbu, Shuntaro Tamaki, Kazuya Saito, Shuutaroh Yuasa, Masaaki Yoshikawa, Takuya Seshita, Hajime Gotoh, Takahiro Imada, Kensuke Yamaji, Akira Suzuki
  • Patent number: 9507306
    Abstract: A fixing device for fixing an unfixed image onto a recording medium includes a fixing belt, a nip forming member, an opposing rotary member, a heater, and a temperature detector. The fixing belt is formed into a loop to move endlessly and fix the unfixed image on the recording medium. The nip forming member is disposed inside the loop formed by the fixing belt. The opposing rotary member contacts the nip forming member via the fixing belt to form a nip portion therebetween while rotating. The heater heats the fixing belt at a place other than the nip portion. The temperature detector detects a temperature of the surface of the fixing belt. The temperature detector detects the temperature near a place of the fixing belt that easily deforms as the fixing belt is heated by the heater.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: November 29, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Uchitani, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Toshihiko Shimokawa, Kensuke Yamaji, Teppei Kawata, Takamasa Hase, Takuya Seshita, Shuutaroh Yuasa, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki, Hiroshi Yoshinaga
  • Publication number: 20160327891
    Abstract: An image forming apparatus includes a first heater disposed opposite and heating at least a center of a fixing belt in an axial direction thereof and a second heater disposed opposite and heating at least a lateral end of the fixing belt in the axial direction thereof. A power supply supplies power to the first heater and the second heater. A controller that controls the power supply includes a calculator to calculate an elapsed time elapsed after at least one of the first heater and the second heater starts heating the fixing belt. The controller controls the power supply to supply power to the first heater and the second heater such that a power density of the second heater is greater than a power density of the first heater when the elapsed time calculated by the calculator is smaller than a predetermined time.
    Type: Application
    Filed: July 22, 2016
    Publication date: November 10, 2016
    Inventors: Yutaka IKEBUCHI, Hiroshi YOSHINAGA, Takayuki SEKI, Yuji ARAI, Ryuuichi MIMBU, Shuntaro TAMAKI, Kazuya SAITO, Shuutaroh YUASA, Toshihiko SHIMOKAWA, Masaaki YOSHIKAWA, Toshiharu HACHISUKA