Patents by Inventor Kenji Ishii

Kenji Ishii 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).

  • Sheet conveyor, cooling device, and image forming apparatus
    Patent number: 9267733
    Abstract: A sheet conveyor includes a first conveyance belt, a second conveyance belt, a first driving roller, a second driving roller, a first gear, and a second gear. In switching between sandwich and separation states, an axial center of a rotation shaft of the first or second gear moves on a movement plane substantially perpendicular to a direction in which the first conveyance belt and the second conveyance belt convey a sheet. Where L represents diameter of a tooth edge circle of the second gear in unit of millimeter and T1 represents a chordal tooth thickness of the second gear, an acute-side angle ? in unit of degree (°) formed by the movement plane and an interaxial-center plane including the axial center of the rotation shaft of each of the first gear and the second gear in the sandwich state is within a range represented by the following Formula 1: Tan?1(2×T1/L)<|?|<45°.
    Type: Grant
    Filed: September 16, 2014
    Date of Patent: February 23, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuji Karikusa, Kenji Ishii
  • COOLING DEVICE AND IMAGE FORMING APPARATUS INCLUDING SAME
    Publication number: 20160048106
    Abstract: A recording-material cooling device includes a first belt, a first cooling unit, and a second cooling unit. The first belt is disposed at a first face side of a recording material. The first cooling unit has a first heat absorbing surface to contact the first belt to absorb heat of the recording material. The second cooling unit has a second heat absorbing surface to directly or indirectly contact the recording material to absorb heat of the recording material. The second cooling unit is disposed at a second face side of the recording material. The first and second cooling units are offset from each other in a transport direction of the recording material. Each of the first and second surfaces has a shape in which an inner area protrudes beyond opposed ends in the transport direction. The first and second surfaces overlap each other in a direction crossing the transport direction.
    Type: Application
    Filed: October 27, 2015
    Publication date: February 18, 2016
    Inventors: Tomoyasu HIRASAWA, Kenichi TAKEHARA, Hiromitsu FUJIYA, Keisuke YUASA, Yasuaki TODA, Yutaka SHOJI, Kenji ISHII, Makoto NAKURA, Susumu TATEYAMA, Hiroaki MIYAGAWA, Keisuke IKEDA, Takeshi WATANABE
  • COOLING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING THE COOLING DEVICE
    Publication number: 20160026125
    Abstract: A cooling device, which is includable to an image forming apparatus, includes a conveyor, a cooler, and at least one roller. The conveyor conveys a recording medium with a first roller and a second roller each of which is in a loop. The cooler is disposed within the loop of the second belt and cools the recording medium discharged from a fixing device. The at least one roller is a roller within the loop of the first belt and between a first end roller disposed at an end of the first belt facing a plane of a conveyance path. Alternatively, the at least one roller is multiple rollers within the loop of the first belt and contacts an inner circumferential surface of the first belt against the cooler and an upstream roller of the multiple rollers has a smallest pressing force of the multiple rollers.
    Type: Application
    Filed: July 23, 2015
    Publication date: January 28, 2016
    Inventors: Kenji ISHII, Hiroaki MIYAGAWA, Tohru MATSUMOTO, Masahiro YAMAZAKI, Keisuke KUBOTA
  • Fixing device and image forming apparatus
    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
  • Fixing device and image forming apparatus including same
    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
  • Fixing device and image forming apparatus incorporating same
    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
  • COMPOSITION, AND METHOD FOR PRODUCING FOAM MOLDED MATERIAL AND ELECTRIC WIRE
    Publication number: 20160005506
    Abstract: The present invention aims to provide a composition which can provide molded foams and foamed electric wires having a small average cell size and a high expansion ratio. The composition of the present invention includes a fluororesin; and boron nitride having an average particle size of 10.5 ?m or greater, or boron nitride having a particle size distribution represented by (D84?D16)/D50 of 1.2 or lower.
    Type: Application
    Filed: January 15, 2014
    Publication date: January 7, 2016
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Tadaharu ISAKA, Kenji ISHII, Takeshi SHIMONO
  • FIXING DEVICE AND IMAGE FORMING APPARATUS
    Publication number: 20160004197
    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: September 11, 2015
    Publication date: January 7, 2016
    Applicant: 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
  • Fixing device and image forming apparatus
    Patent number: 9229389
    Abstract: A fixing device includes an endless belt, a heater disposed opposite the endless belt to heat the endless belt, and a pressing rotary body contacting an outer circumferential surface of the endless belt. A nip formation pad presses against the pressing rotary body via the endless belt to form a fixing nip between the endless belt and the pressing rotary body, through which a recording medium is conveyed. The nip formation pad includes a nip face disposed opposite the endless belt. The nip face includes a first region having an increased thermal conductivity and a second region having a decreased thermal conductivity and being adjacent to the first region in an axial direction of the endless belt.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: January 5, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hiromasa Takagi, Kenji Ishii, Arinobu Yoshiura
  • FIXING DEVICE CAPABLE OF ENHANCING DURABILITY OF ENDLESS BELT AND IMAGE FORMING APPARATUS INCORPORATING THE SAME
    Publication number: 20150378290
    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: September 8, 2015
    Publication date: December 31, 2015
    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
  • Cooling device and image forming apparatus including same
    Patent number: 9217979
    Abstract: A recording-material cooling device includes a first belt, a first cooling unit, and a second cooling unit. The first belt is disposed at a first face side of a recording material. The first cooling unit has a first heat absorbing surface to contact the first belt to absorb heat of the recording material. The second cooling unit has a second heat absorbing surface to directly or indirectly contact the recording material to absorb heat of the recording material. The second cooling unit is disposed at a second face side of the recording material. The first and second cooling units are offset from each other in a transport direction of the recording material. Each of the first and second surfaces has a shape in which an inner area protrudes beyond opposed ends in the transport direction. The first and second surfaces overlap each other in a direction crossing the transport direction.
    Type: Grant
    Filed: December 26, 2013
    Date of Patent: December 22, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoyasu Hirasawa, Kenichi Takehara, Hiromitsu Fujiya, Keisuke Yuasa, Yasuaki Toda, Yutaka Shoji, Kenji Ishii, Makoto Nakura, Susumu Tateyama, Hiroaki Miyagawa, Keisuke Ikeda, Takeshi Watanabe
  • COMPOSITION, AND METHOD FOR PRODUCING FOAM MOLDED MATERIAL AND ELECTRIC WIRE
    Publication number: 20150353700
    Abstract: A composition which can provide foamed moldings and foamed electric wires having a small average cell size and a high foam content and causing fewer sparks. The composition includes a fluororesin (A) and a compound (B) which is a sulfonic acid or a salt thereof. The sulfonic acid is represented by the following formula (1): F(CF2)nSO3H (1) wherein n is 4 or 5, or the following formula (2): F(CF2)nCH2CH2SO3H (2) wherein n is 4 or 5. Also disclosed is a foamed molding formed from the composition and a method for producing a foamed molding.
    Type: Application
    Filed: January 15, 2014
    Publication date: December 10, 2015
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Tadaharu ISAKA, Kenji ISHII, Takeshi SHIMONO
  • Image forming apparatus including a fixing device
    Patent number: 9207596
    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: September 2, 2014
    Date of Patent: December 8, 2015
    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
  • Fixing device and image forming apparatus
    Patent number: 9158250
    Abstract: 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: Grant
    Filed: January 9, 2012
    Date of Patent: October 13, 2015
    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
  • Fixing device capable of enhancing durability of endless belt and image forming apparatus incorporating the same
    Patent number: 9152108
    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 7, 2014
    Date of Patent: October 6, 2015
    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
  • Fixing device and image forming apparatus including same
    Patent number: 9152106
    Abstract: A fixing device includes a rotary fixing member, a heater, a pressing member, a nip formation member, a reinforcement member, a sliding sheet, and a holding member. The nip formation member is disposed at an inner circumferential side of the fixing member and pressed by the pressing member via the fixing member to form a nipping portion. The reinforcement member is stationarily disposed in an internal diameter area of the fixing member to support the nip formation member. The sliding sheet is disposed between the nip formation member and an inner circumferential face of the fixing member. The holding member is disposed at a member differing from the nip formation member to hold the sliding sheet in a state in which the sliding sheet is in close contact with a nipping face of the nip formation member facing the nipping portion.
    Type: Grant
    Filed: August 29, 2013
    Date of Patent: October 6, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiki Yamaguchi, Takayuki Seki, Yuji Arai, Yutaka Ikebuchi, Shuntaroh Tamaki, Kazuya Saito, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Toshihiko Shimokawa, Arinobu Yoshiura, Kensuke Yamaji, Hiromasa Takagi, Naoki Iwaya, Takahiro Imada, Akira Suzuki
  • FIXING DEVICE AND IMAGE FORMING APPARATUS
    Publication number: 20150268597
    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: Application
    Filed: May 5, 2015
    Publication date: September 24, 2015
    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
  • Fixing device and image forming apparatus
    Patent number: 9141047
    Abstract: A fixing device capable of shifting to a sleep state includes a heat source; a rotatable fixing member that is partly heated by the heat source to heat an unfixed image carrying surface of a recording medium; a rotatable pressing member that is in pressure contact with the fixing member to form a nip portion between the pressing member and the fixing member; a rotation drive unit that directly or indirectly rotates the fixing member; a temperature detecting unit that detects a temperature of the fixing member; and a controller configured to prohibit the fixing device from shifting to the sleep state when the temperature of the fixing member in a region facing the heat source is equal to or more than a predetermined temperature T1 at a point when a predetermined time period t1 has elapsed from the stop of rotation drive of the rotation drive unit.
    Type: Grant
    Filed: April 22, 2015
    Date of Patent: September 22, 2015
    Assignee: RICOH COMPANY, LIMITED
    Inventors: Takeshi Uchitani, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Hiroshi Yoshinaga, Arinobu Yoshiura, Teppei Kawata, Takamasa Hase, Hajime Gotoh, Takuya Seshita, Kazuya Saito, Toshihiko Shimokawa, Kensuke Yamaji, Shuutaroh Yuasa, Akira Suzuki, Shinichi Namekata, Ryota Yamashina, Yasunori Ishigaya
  • FIXING DEVICE AND IMAGE FORMING APPARATUS
    Publication number: 20150261157
    Abstract: A fixing device includes: a fixing member that is rotatable and in an endless shape; a heat source that heats the fixing member; a nip forming member that is arranged inside the fixing member; and a pressurizing member that is pressurized to be in contact with the nip forming member through the fixing member, to form a fixing nip. The fixing device fixes an unfixed image on a recording medium by passing the recording medium that carries the unfixed image through the fixing nip. The nip forming member includes a base layer, and a high thermal-conductive layer that is arranged on a surface layer of the base layer on a fixing nip side, and that has higher thermal conductivity than the base layer, and in the high thermal-conductive layer, a low thermal-conductive portion is arranged near an end portion in an axial direction of the fixing member.
    Type: Application
    Filed: March 13, 2015
    Publication date: September 17, 2015
    Inventors: Motoyoshi YAMANO, Kohichi UTSUNOMIYA, Hiromasa TAKAGI, Kenji ISHII, Takayuki SEKI, Keitaro SHOJI, Hideo NAGAFUJI, Yuji ARAI, Arinobu YOSHIURA, Shohei SAITO, Qifeng CUI, Yutaka IKEBUCHI
  • FIXING DEVICE AND IMAGE FORMING APPARATUS
    Publication number: 20150261155
    Abstract: A fixing device includes: a rotatable fixing member formed as an endless belt; a heat source to heat the fixing member; a nip-forming member being not rotatable and arranged inside the fixing member; and a pressure member arranged outside the fixing member and forming a nip between the pressure member and the fixing member. The nip-forming member is formed of a first heat transmission unit and a sliding sheet. The first heat transmission unit includes an abutting part abutting the fixing member with the sliding sheet therebetween, and a bent part or bent parts extending inside the fixing member at upstream or upstream and downstream of the nip in a transport direction of a recording medium. A retaining part to catch and retain the sliding sheet is provided at a tip of at least the bent part at upstream of the nip in the transport direction.
    Type: Application
    Filed: March 11, 2015
    Publication date: September 17, 2015
    Inventors: Arinobu YOSHIURA, Hideo NAGAFUJI, Yuji ARAI, Kohichi UTSUNOMIYA, Shohei SAITO, Qifeng CUI, Yutaka IKEBUCHI, Motoyoshi YAMANO, Kenji ISHII, Hiromasa TAKAGI, Keitaro SHOJI