Patents by Inventor Takamasa Hase

Takamasa Hase 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: 8918042
    Abstract: A fixing device for fixing an image on a recording medium includes a rotatable endless fixing rotary member, a heating source which heats the fixing rotary member, an opposite rotary member in contact with the fixing rotary member, a nip forming member provided inside the fixing rotary member and in contact with the opposite rotary member via the fixing rotary member to form a nip portion to which the recording medium is fed, holding members rotatably holding end portions of the fixing rotary member, and protecting members provided between the holding members and end surfaces of the fixing rotary member to protect the end portions. Each of the protecting members has an opposite surface facing the corresponding end surface of the fixing rotary member, and including an inner diameter-side end edge having an inclined surface inclined in an inner diameter direction and away from the fixing rotary member.
    Type: Grant
    Filed: November 12, 2012
    Date of Patent: December 23, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Takahiro Imada, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Hiroshi Yoshinaga, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Toshihiko Shimokawa, Kensuke Yamaji, Teppei Kawata, Takamasa Hase, Shuutaroh Yuasa, Takuya Seshita, Takeshi Uchitani, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki
  • Publication number: 20140369703
    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: September 2, 2014
    Publication date: December 18, 2014
    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: 20140363184
    Abstract: An image forming apparatus, including: electrostatic latent image bearing member; electrostatic latent image forming unit; developing unit configured to develop with toner to form visible image; transferring unit; fixing unit; and discharging unit, the toner containing binder resin, colorant, and releasing agent, the binder resin containing crystalline resin containing urethane or urea bond, or both, the toner satisfying: C/(C+A)?0.15, C being integrated intensity of part of spectrum derived from crystalline structure of the binder resin, A being integrated intensity of part of the spectrum derived from non-crystalline structure, the spectrum being diffraction spectrum of the toner as obtained by X-ray diffraction spectroscopy, storage elastic modulus G?(70) of the toner at 70° C. being 5.0×104 Pa?G?(70)?1.0×106 Pa, and storage elastic modulus G?(160) thereof at 160° C. being 1.0×103 Pa?G?(160)?1.
    Type: Application
    Filed: May 29, 2014
    Publication date: December 11, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Hideyuki Santo, Yukiko Iwasaki, Takamasa Hase
  • Patent number: 8909117
    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: December 17, 2012
    Date of Patent: December 9, 2014
    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: 20140342283
    Abstract: To provide a toner for developing an electrostatic image, the toner including toner particles, wherein the toner particles contain: a non-crystalline resin A; and a crystalline resin, wherein the crystalline resin contains a crystalline resin C containing a urethane bond, or a urea bond, or both thereof, and wherein the toner particles each have a sea-island structure, where the resin C is dispersed in the non-crystalline resin on a cross-section of the toner particle.
    Type: Application
    Filed: May 12, 2014
    Publication date: November 20, 2014
    Inventors: Atsushi Yamamoto, Hiroshi Yamada, Takamasa Hase, Kohsuke Nagata
  • Patent number: 8891990
    Abstract: An image forming apparatus includes a fixing device disposed downstream from an image forming device in a recording medium conveyance direction to fix a toner image formed by the image forming device on a recording medium. The fixing device includes a pressing rotary body separatably pressed against a fixing rotary body to form a nip therebetween through which the recording medium bearing the toner image passes, and a moving assembly to move the pressing rotary body bidirectionally to press the pressing rotary body against the fixing rotary body and separate the pressing rotary body from the fixing rotary body. A controller controls the moving assembly to change a post-fixing pressing time period for which the moving assembly presses the pressing rotary body against the fixing rotary body after the recording medium bearing the toner image is discharged from the nip according to image data.
    Type: Grant
    Filed: September 27, 2011
    Date of Patent: November 18, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Shuutaroh Yuasa, Tadashi Ogawa, Takeshi Uchitani, Satoshi Ueno, Teppei Kawata, Takamasa Hase, Kazuya Saito, Kensuke Yamaji
  • Publication number: 20140334838
    Abstract: A method for forming a toner image on a recording medium includes receiving a job, rotating a pressing rotary body in a predetermined direction of rotation, rotating a flexible endless belt disposed opposite the pressing rotary body to form a nip therebetween, turning on a belt heater disposed opposite to an inner circumferential surface of the flexible endless belt, conveying the recording medium bearing the toner image through the nip, turning off the belt heater for a predetermined first time period after the recording medium is discharged from the nip while the flexible endless belt and the pressing rotary body rotate, stopping the flexible endless belt and the pressing rotary body, turning on the belt heater when a predetermined second time period elapses after stopping the flexible endless belt and the pressing rotary body, and turning off the belt heater.
    Type: Application
    Filed: July 23, 2014
    Publication date: November 13, 2014
    Inventors: Takamasa HASE, Tadashi Ogawa, Takeshi Uchitani, Satoshi Ueno, Teppei Kawata, Kazuya Saito, Shuutaroh Yuasa, Kensuke Yamaji
  • Patent number: 8886103
    Abstract: A fixing device includes an endless belt and a belt holder contacting and rotatably supporting each lateral end of the endless belt in an axial direction thereof. A first protection ring and a second protection ring are interposed between the endless belt and the belt holder in the axial direction of the endless belt and rotatable in accordance with rotation of the endless belt to protect each lateral end of the endless belt as the endless belt is skewed in the axial direction thereof and brought into contact with the first protection ring. A friction coefficient between the first protection ring and the second protection ring is smaller than a friction coefficient between the first protection ring and the endless belt.
    Type: Grant
    Filed: January 22, 2013
    Date of Patent: November 11, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Kensuke Yamaji, Masahiko Satoh, Masaaki Yoshikawa, Hiroshi Yoshinaga, Kenji Ishii, Tadashi Ogawa, Takeshi Uchitani, Hiromasa Takagi, Naoki Iwaya, Teppei Kawata, Arinobu Yoshiura, Takahiro Imada, Hajime Gotoh, Takamasa Hase, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Akira Suzuki
  • Patent number: 8886101
    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: November 15, 2012
    Date of Patent: November 11, 2014
    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: 8867976
    Abstract: A fixing device includes a support member fixedly provided inside a loop formed by a fixing member to support a nip formation member provided inside the loop formed by the fixing member. A biasing member is provided between the support member and a heater support that supports a laminated heater that generates heat to be transmitted to the fixing member. The heater support thermally expands in a first direction due to heat generated by the laminated heater. The biasing member applies bias to the heater support in a second direction opposite the first direction and in which the heater support presses the laminated heater against an inner circumferential surface of the fixing member.
    Type: Grant
    Filed: February 16, 2011
    Date of Patent: October 21, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Ippei Fujimoto, Kenji Ishii, Masaaki Yoshikawa, Hiroshi Yoshinaga, Naoki Iwaya, Yoshiki Yamaguchi, Yutaka Ikebuchi, Tetsuo Tokuda, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa, Takuya Seshita
  • Patent number: 8855506
    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: February 8, 2013
    Date of Patent: October 7, 2014
    Assignee: Ricoh Company, Limited
    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: 20140270874
    Abstract: An image forming apparatus includes: an image bearing member; a charger; an irradiator; a development device having an accommodation unit to accommodate toner to obtain a visible image; a transfer device; and a fixing device to fix the visible image transferred onto a recording medium. The fixing device having a fixing rotation member; and a pressure rotation member to form a nipping portion by contacting the fixing rotation member, wherein the surface pressure of the nipping portion is 1.5 kgf/cm2 or less, wherein the fixing rotation member has a Martens hardness of 1.0 N/mm2 or less at 23° C., wherein the ratio of the projected area of a single particle of the toner onto the recording medium at 120° C. to the projected area of a single particle of the toner onto the recording medium at 23° C. is 1.60 or less.
    Type: Application
    Filed: February 26, 2014
    Publication date: September 18, 2014
    Inventors: Takamasa Hase, Shinya Nakayama, Atsushi Yamamoto, Hideyuki Santo, Minoru Masuda, Yukiko Iwasaki, Tsuneyasu Nagatomo
  • Patent number: 8831494
    Abstract: A fixing device includes a substantially cylindrical metal member, a heater positioned to heat the metal member, an endless, flexible fixing member disposed rotatably around the metal member and heated by the metal member to heat and fix a toner image, a rotary pressing member disposed opposite the metal member and pressed against an outer circumferential surface of the fixing member to form a nip therebetween, and a stationary member disposed at an inner circumferential surface side of the fixing member and pressed by the pressing member via the fixing member to form the nip. At least when the fixing member is relatively moved toward the metal member during assembly of the fixing member with the metal member, the metal member includes at least one protruding portion protruding axially outward from an axial end of the metal member to guide the fixing member axially toward the metal member.
    Type: Grant
    Filed: February 15, 2011
    Date of Patent: September 9, 2014
    Assignee: Ricoh Company Limited
    Inventors: Yutaka Ikebuchi, Hiroshi Yoshinaga, Toshihiko Shimokawa, Masaaki Yoshikawa, Yoshiki Yamaguchi, Naoki Iwaya, Tetsuo Tokuda, Kenji Ishii, Ippei Fujimoto, Shuntaroh Tamaki, Akira Shinshi, Takahiro Imada, Takamasa Hase, Kenichi Hasegawa
  • Patent number: 8831498
    Abstract: A fixing device includes a rotatable, endless flexible belt, an elongated stationary pad, a rotatable pressure member, a rotary driver, a releasable biasing mechanism, a first guide member, and a second guide member. The endless flexible belt is looped into a generally cylindrical configuration. The elongated stationary pad is stationarily disposed inside the loop of the belt. The rotatable pressure member is disposed parallel to the stationary pad with the belt interposed between the pressure member and the stationary pad. The rotary driver is operatively connected with the pressure member to impart torque to the pressure member. The releasable biasing mechanism is operatively connected with the pressure member to apply a releasable pressure to the pressure member against the belt in a load direction. The first guide member defines a first elongated opening. The second guide member defines a second elongated opening.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: September 9, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Naoki Iwaya, Masahiko Satoh, Masaaki Yoshikawa, Hiroshi Yoshinaga, Kenji Ishii, Tadashi Ogawa, Hiromasa Takagi, Takeshi Uchitani, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Teppei Kawata, Toshihiko Shimokawa, Arinobu Yoshiura, Takamasa Hase, Shuutaroh Yuasa, Kensuke Yamaji
  • Patent number: 8811843
    Abstract: An image forming apparatus for performing a copier job and a printer job includes a controller operatively connected to a fixing rotary body heater and a pressing rotary body heater to control the fixing rotary body heater and the pressing rotary body heater. The controller activates a standby mode after the copier job and the printer job are finished in which the controller turns off at least the fixing rotary body heater and a subsequent off mode in which the controller turns off the pressing rotary body heater and the fixing rotary body heater, and identifies which of the copier job and the printer job is to be performed to turn on and off the pressing rotary body heater in the standby mode according to the identified job.
    Type: Grant
    Filed: October 25, 2011
    Date of Patent: August 19, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Takamasa Hase, Tadashi Ogawa, Takeshi Uchitani, Satoshi Ueno, Teppei Kawata, Kazuya Saito, Shuutaroh Yuasa, Kensuke Yamaji
  • Patent number: 8811837
    Abstract: A fixing device includes a substantially cylindrical metal member, a heater, an endless, flexible fixing member, a rotary pressing member, a stationary member, a first temperature detector, and a second temperature detector. The first temperature detector is disposed upstream from a nip in a rotation direction of the fixing member to detect a surface temperature of the fixing member. The second temperature detector is disposed downstream from the nip in a rotation direction of the pressing member to detect a surface temperature of the pressing member. When a difference between a surface temperature of the fixing member detected by the first temperature detector and a surface temperature of the pressing member detected by the second temperature detector after a predetermined time has elapsed since the first temperature detector detects the surface temperature of the fixing member is greater than a predetermined threshold, the heater stops heating the metal member.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: August 19, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yoshinaga, Kenichi Hasegawa, Masaaki Yoshikawa, Kenji Ishii, Akira Shinshi, Naoki Iwaya, Yutaka Ikebuchi, Tetsuo Tokuda, Ippei Fujimoto, Yoshiki Yamaguchi, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa
  • Patent number: 8811842
    Abstract: The fixing device using an electromagnetic induction heating (IH) method includes a fixing sleeve having a heating layer, a pressure roller to form a nip while contacting the fixing roller and rotate to drive the fixing sleeve, a temperature detector to detect a temperature on a circumference of the fixing sleeve, and an excitation coil provided near the fixing sleeve and configured to perform induction heating of the heating layer of the fixing sleeve based on the detection result from the temperature detector. The fixing device is configured to change a rotation speed of the fixing sleeve in a standby time during which the fixing sleeve, while rotating, is controlled to be heated so as to maintain a target temperature when a periodic temperature difference occurs on a circumference of the fixing rotary member and having a fluctuation amplitude larger than a predetermined value compared to the target temperature.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: August 19, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Takamasa Hase, Masanao Ehara, Kenji Ishii, Tadashi Ogawa, Satoshi Ueno, Hiroshi Seo, Takahiro Imada, Shuutaroh Yuasa
  • Patent number: 8811874
    Abstract: A belt device includes a flange assembly including a tube inserted into a loop formed by an endless belt at each lateral end of the endless belt in an axial direction thereof and a slip ring slidably contacting a groove mounted on the tube. An inner diameter ID 51 of the slip ring through a rotation axis of the slip ring is smaller than a minimum outer diameter OD50a of the tube through the rotation axis of the slip ring. The minimum outer diameter OD50a is smaller than a maximum outer diameter OD21 of a track of the endless belt rotating in a predetermined direction of rotation through the rotation axis of the slip ring. The maximum outer diameter OD21 is smaller than an outer diameter OD51 of the slip ring through the rotation axis of the slip ring.
    Type: Grant
    Filed: July 25, 2012
    Date of Patent: August 19, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshihiko Shimokawa, Kenji Ishii, Masaaki Yoshikawa, Hiroshi Yoshinaga, Naoki Iwaya, Yoshiki Yamaguchi, Yutaka Ikebuchi, Tetsuo Tokuda, Takahiro Imada, Takamasa Hase, Ippei Fujimoto, Takuya Seshita
  • Patent number: 8774666
    Abstract: A fixing device includes a heating device to heat an endless rotary body with radiant heat, a power source to supply power to the heating device, a first heat source to heat a region on the endless rotary body corresponding to a width of the small size sheet, and a second heat source to heat regions on the endless rotary body corresponding to both widthwise ends of the large size sheet outside the width of the small size sheet. The power source supplies power only to the first heat source when the small size sheet is printed and to both the first and second heat sources when the large size sheet is printed. The power source supplies more power to the first heat source when the small size sheet is printed than when the large size sheet is printed within a maximum power available to the fixing device.
    Type: Grant
    Filed: December 17, 2012
    Date of Patent: July 8, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuya Saito, Takeshi Uchitani, Takamasa Hase, Shuutaroh Yuasa, Ippei Fujimoto, Shinichi Namekata, Ryota Yamashina, Hiroshi Seo, Takumi Waida
  • Patent number: 8750776
    Abstract: A fixing roller includes a fixing sleeve including a heat generating layer; and a support roll inserted into the fixing sleeve to support the fixing sleeve and including a foam layer constituting an outer circumferential surface of the support roll. The foam layer includes recesses exposing pores containing air; and non-recessed portions contiguous to the recesses and adhered to an inner circumferential surface of the fixing sleeve.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: June 10, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Tadashi Ogawa, Takeshi Uchitani, Satoshi Ueno, Takamasa Hase, Teppei Kawata, Kazuya Saito, Shuutaroh Yuasa, Kensuke Yamaji