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: 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
  • Patent number: 9454114
    Abstract: A fixing device including a fixing member, an opposing member, a plurality of heat sources, and a voltage detector. The opposing member is disposed opposite the fixing member to contact the fixing member to form a nip portion at which an unfixed image on a recording medium is fixed. The plurality of heat sources heats the fixing member. The voltage detector detects an applied voltage of at least one of the plurality of heat sources. Upon detection of the applied voltage of the heat sources by the voltage detector, a voltage is applied to at least one of the heat sources.
    Type: Grant
    Filed: April 9, 2015
    Date of Patent: September 27, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Takamasa Hase, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tadashi Ogawa, Takeshi Uchitani, Hiromasa Takagi, Naoki Iwaya, Teppei Kawata, Takuya Seshita, Arinobu Yoshiura, Takahiro Imada, Hajime Gotoh, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Kensuke Yamaji, Akira Suzuki
  • Patent number: 9448514
    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: December 9, 2014
    Date of Patent: September 20, 2016
    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: 9439070
    Abstract: A user authentication system 4 includes an authentication processing module 44, which authenticates a user terminal device 1 based on received account identification information and authentication information; a fraud determination module 48, which detects fraud in a login request from the user terminal device 1 based on the access history of the user terminal device 1; and a response control module 46, which allows the user of said user terminal device 1 to log in to a predetermined account if no fraud is detected in the login request and the user terminal device 1 has been authenticated, and, on the other hand, allows the user of said user terminal device 1 to log in to a dummy account in accordance with predetermined criteria if fraud is detected in the login request from the user terminal device 1.
    Type: Grant
    Filed: April 17, 2015
    Date of Patent: September 6, 2016
    Assignee: DeNA CO., LTD.
    Inventors: Toshiharu Sugiyama, Masaaki Yoshikawa
  • Patent number: 9405250
    Abstract: A fixing device includes at least one heater disposed opposite an inner circumferential surface of an endless rotary body to heat the endless rotary body and a shield interposed between the endless rotary body and the at least one heater to shield the endless rotary body from heat radiated from the at least one heater. A first size recording medium passes over a first passage region of the endless rotary body and a second size recording medium passes over a second passage region of the endless rotary body. The shield includes a notch disposed opposite a lateral end of the second passage region of the endless rotary body in an axial direction thereof. The lateral end of the second passage region overlaps a non-passage region of the endless rotary body in the axial direction thereof where the first size recording medium does not pass.
    Type: Grant
    Filed: February 25, 2015
    Date of Patent: August 2, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Tadashi Ogawa, Masahiko Satoh, Masaaki Yoshikawa, Hiroshi Yoshinaga, Kenji Ishii, Takeshi Uchitani, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Takamasa Hase, Toshihiko Shimokawa, Shuutaroh Yuasa, Teppei Kawata, Arinobu Yoshiura, Kensuke Yamaji, Akira Suzuki
  • Patent number: 9405242
    Abstract: According to an embodiment, provided is a fixing device that includes: a rotatable fixing member that heats a recording medium on a side carrying an unfixed image; a rotatable pressing member that is pressed and is contacted with the fixing member to form a nip portion between the pressing member and the fixing member; a heat source heating the fixing member; a relay switch provided in an energizing path for the heat source; a temperature detection sensor detecting a temperature of the fixing member; and a control unit that controls energization of the heat source according to the temperature detected by the temperature detection sensor. The control unit keeps the relay switch in an off state if the temperature of the fixing member is equal to or more than a predetermined temperature when the fixing member has stopped rotation.
    Type: Grant
    Filed: May 4, 2015
    Date of Patent: August 2, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Takamasa Hase, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Takeshi Uchitani, Shuutaroh Yuasa, Masaaki Yoshikawa, Hiroshi Yoshinaga, Hiromasa Takagi, Naoki Iwaya, Takahiro Imada, Hajime Gotoh, Takuya Seshita, Ryota Yamashina, Yasunori Ishigaya
  • Patent number: 9405270
    Abstract: A fixing device capable of incorporating in an image forming apparatus includes a belt unit including a rotatable elastic endless belt having a sleeve shape without a driving shaft and a nip forming member disposed contactable against an inner surface of the endless belt, and a pressing member to form a nip contact portion through which a recording medium passes by pressing against the nip forming member via the endless belt. The endless belt is configured to be removable from the fixing device without contacting the endless belt.
    Type: Grant
    Filed: January 29, 2013
    Date of Patent: August 2, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Tadashi Ogawa, Kenji Ishii, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Yuji Arai, Yoshiki Yamaguchi, Hiromasa Takagi, Naoki Iwaya, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Masaaki Yoshikawa
  • Patent number: 9367010
    Abstract: According to an embodiments, provided is a fixing device that includes: an endless fixing belt, heats and melts a toner image, and has flexibility; a stationary member that is set stationary on an inner peripheral surface side of the fixing belt and comes into contact under pressure to form a nip portion; and a reinforcement member that is set stationary on the inner peripheral surface side of the fixing belt and comes into abutment with the stationary member. If it is assumed that a length of the nip portion in a direction of conveyance of the recording medium is designated as A; and a length between an upstream-side abutment portion and a downstream-side abutment portion at which the stationary member and the reinforcement member come into abutment with each other is designated as B, following relation is established: A<B, and interval B includes interval A.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: June 14, 2016
    Assignee: RICOII COMPANY, LIMITED
    Inventors: Hiromasa Takagi, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tadashi Ogawa, Takahiro Imada, Kazuya Saito, Naoki Iwaya, Toshihiko Shimokawa, Kensuke Yamaji, Teppei Kawata, Takamasa Hase, Shuutaroh Yuasa, Takuya Seshita, Takeshi Uchitani, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki
  • Patent number: 9316972
    Abstract: A fixing device includes a fixing rotary body rotatable in a given direction of rotation and a pressing rotary body pressed against the fixing rotary body to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed. A heater is disposed inside the fixing rotary body to heat the fixing rotary body. A reflector, disposed opposite an inner circumferential surface of the fixing rotary body via the heater, reflects light emitted from the heater onto the fixing rotary body. The reflector includes a movable portion movable relative to the heater to direct the light emitted from the heater onto a variable heating span of the fixing rotary body spanning in an axial direction thereof. The variable heating span varies depending on a width of the recording medium in the axial direction of the fixing rotary body.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: April 19, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Yuji Arai, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Yoshiki Yamaguchi, Hiromasa Takagi, Naoki Iwaya, Takahiro Imada, Hajime Gotoh, Akira Suzuki
  • Patent number: 9310733
    Abstract: A fixing device includes a substantially cylindrical metal member, a heater, an endless, flexible fixing member, a rotary pressing member, and a stationary member. The heater heats the metal member. The fixing member is disposed rotatable around the metal member. An inner circumferential surface of the fixing member is heated by the metal member to heat and fix a toner image. The rotary pressing member is disposed opposite the metal member and pressed against an outer circumferential surface of the fixing member to form a nip between the rotary pressing member and the fixing member through which a recording medium bearing the toner image passes. The stationary member is disposed in pressure contact with the inner circumferential surface of the fixing member, and has an opposing face opposing the rotary pressing member and having a curvature smaller than a curvature of the rotary pressing member.
    Type: Grant
    Filed: February 4, 2011
    Date of Patent: April 12, 2016
    Assignee: Ricoh Company, LTD.
    Inventors: Hiroshi Yoshinaga, Masaaki Yoshikawa, Kenichi Hasegawa, Kenji Ishii, Akira Shinshi, Naoki Iwaya, Yutaka Ikebuchi, Ippei Fujimoto, Yoshiki Yamaguchi, Shuntaroh Tamaki, Tetsuo Tokuda, Takamasa Hase, Takahiro Imada, Toshihiko Shimokawa
  • Publication number: 20160098003
    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: December 11, 2015
    Publication date: April 7, 2016
    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: 9291967
    Abstract: A fixing device that fixes an image on a recording medium includes a rotatable endless belt, deployed in a loop supported by rollers, a nip forming member provided inside the loop formed by the belt, a support member that supports the nip forming member, a counter rotation body disposed outside the loop formed by the belt and configured to form a nip with the belt by being in contact with the nip forming member through the belt, and a heat source configured to heat the belt directly by a radiant heat except at the nip. The support member includes a base portion that contacts the nip forming member and two arms extending from the base portion in a direction away from the nip forming member to partially surround a part of heat generating portion of the heat source.
    Type: Grant
    Filed: November 7, 2014
    Date of Patent: March 22, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Naoki Iwaya, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tadashi Ogawa, Takeshi Uchitani, Hiromasa Takagi, Takuya Seshita, Takahiro Imada, Takamasa Hase, Hajime Gotoh, Arinobu Yoshiura, Teppei Kawata, Toshihiko Shimokawa, Shuutaroh Yuasa, Kazuya Saito, Kensuke Yamaji, Akira Suzuki
  • Publication number: 20160054691
    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: October 30, 2015
    Publication date: February 25, 2016
    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
  • Publication number: 20160036853
    Abstract: To prevent logins to illegitimate sites such as phishing sites, a terminal device according to an embodiment stores authentication information used for login to a destination site in a storage (the authentication information storage area) in association with the site, and determines whether authentication information corresponding to the authentication information input for login to the destination site is stored in the storage in association with a site different from the destination site. The terminal device performs a predetermined alert process in response to the determination that the corresponding authentication information is stored in association with the different site.
    Type: Application
    Filed: July 22, 2015
    Publication date: February 4, 2016
    Inventors: Toshiharu SUGIYAMA, Masaaki YOSHIKAWA
  • Patent number: 9239559
    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: February 8, 2013
    Date of Patent: January 19, 2016
    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: 9239553
    Abstract: A fixing device includes a fixing rotary body and a heater disposed opposite the fixing rotary body. A heat shield is movable in a circumferential direction of the fixing rotary body and interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater. An overheating suppressor is interposed between the heater and the heat shield to shield the heat shield from the heater. The heat shield includes an intermediate portion spanning in the circumferential direction of the fixing rotary body and movable between a shield position where the intermediate portion is disposed opposite the heater directly and a retracted position where the intermediate portion is disposed opposite the heater via the overheating suppressor.
    Type: Grant
    Filed: May 5, 2015
    Date of Patent: January 19, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuji Arai, Takayuki Seki, Yoshiki Yamaguchi, Shuntaroh Tamaki, Yutaka Ikebuchi, Kazuya Saito, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Masaaki Yoshikawa, Hiromasa Takagi, Naoki Iwaya, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Hiroshi Yoshinaga, Ryuuichi Mimbu, Takuya Seshita, Takeshi Yamamoto, Shuutaroh Yuasa
  • Patent number: 9235177
    Abstract: A fixing device comprises a rotatable fixing member to apply heat to a recording medium bearing an unfixed image thereon, a heat source to heat the fixing member, and a rotatable pressing member pressing against the fixing member forming a nip therebetween. A driving source rotates and drives the fixing member and the pressing member. An overheat safety device has a relay to open and close a power supply path connected to the heat source. A temperature detector is connected to both the relay and the control unit to detect temperature of the fixing member. The overheat safety device turns off the relay and cuts off power supply to the heat source when the fixing member is overheated. The fixing member is allowed to radiate heat and cool down when the temperature detected by the temperature detector is more than a prescribed level.
    Type: Grant
    Filed: December 31, 2012
    Date of Patent: January 12, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuya Seshita, Masahiko Satoh, Masaaki Yoshikawa, Hiroshi Yoshinaga, Kenji Ishii, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Toshihiko Shimokawa, Kensuke Yamaji, Teppei Kawata, Takamasa Hase, Shuutaroh Yuasa, Takeshi Uchitani, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki, Ryota Yamashina, Yasunori Ishigaya