Patents by Inventor Masanao Ehara

Masanao Ehara 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: 8346117
    Abstract: A fixing device includes a heating source; a heating member heated by the heating source; a pressing member contacting the heating member to form a fixing nip therebetween, at which an unfixed image of toner on a recording sheet is fixed to the recording sheet; a first charging member located at an entrance of the fixing device, from which the recording sheet bearing the unfixed toner image enters the fixing device, so as to face the unfixed toner image. The first charging member is not contacted with the heating member and pressing member, and has a charge with a polarity opposite to a polarity of a charge of the toner to collect floating particles of the toner.
    Type: Grant
    Filed: August 30, 2010
    Date of Patent: January 1, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Kenji Ishii, Tadashi Ogawa, Satoshi Ueno, Hiroshi Seo, Masanao Ehara
  • Publication number: 20120219312
    Abstract: A fixing device includes a fixing rotary body rotatable in a predetermined direction of rotation to radiate infrared rays; a pressing rotary body, rotatable in a direction counter to the direction of rotation of the fixing 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 disposed opposite the fixing rotary body to heat the fixing rotary body; a temperature detector spaced apart from the fixing rotary body to detect a temperature of the fixing rotary body based on the infrared rays from the fixing rotary body and disposed below the fixing nip in a vertical direction; and a tube disposed between the fixing rotary body and the temperature detector, the tube through which the infrared rays from the fixing rotary body enter the temperature detector.
    Type: Application
    Filed: February 6, 2012
    Publication date: August 30, 2012
    Inventors: Shuutaroh YUASA, Masanao EHARA, Tadashi OGAWA, Satoshi UENO, Hiroshi SEO, Teppei KAWATA, Shuntaroh TAMAKI, Takamasa HASE, Kazuya SAITO, Kensuke YAMAJI
  • Patent number: 8244168
    Abstract: An image forming apparatus includes a transfer device that transfers a toner image formed on an image bearer onto a transfer sheet and a fixing device that fixes the toner image onto the transfer sheet. The transfer device is freely movable between an operational position and a non-operational position and includes a contacting section that directly contacts the fixing device and determines a position of the transfer device.
    Type: Grant
    Filed: June 23, 2008
    Date of Patent: August 14, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Masanao Ehara, Hiroshi Yoshinaga, Naoki Iwaya, Yoshiki Yamaguchi
  • Publication number: 20120177424
    Abstract: A fixing device includes an induction heater constructed of an exciting coil, a first pair of degaussing coils, and a second pair of degaussing coils. A controller turns off the exciting coil while the controller turns on one of the first pair of degaussing coils and the second pair of degaussing coils and at the same time turns off the other one of the first pair of degaussing coils and the second pair of degaussing coils, and then turns on the exciting coil for an extra time period corresponding to reserved power not supplied to the exciting coil while the exciting coil is turned off.
    Type: Application
    Filed: December 27, 2011
    Publication date: July 12, 2012
    Applicant: RICOH COMPANY, LTD.
    Inventors: Kazuya Saito, Masanao Ehara, Tadashi Ogawa, Takeshi Uchitani, Satoshi Ueno, Teppei Kawata, Takamasa Hase, Shuutaroh Yuasa, Kensuke Yamaji
  • Patent number: 8195075
    Abstract: An image forming apparatus includes a fixing unit for fixing a toner image on a recording medium. In at least one embodiment, the fixing unit includes a fixing member configured to heat and melt a toner. Further, in at least one embodiment, the fixing member has a surface contacting the toner image and includes a wettability not greater than 38 mN/m.
    Type: Grant
    Filed: September 10, 2007
    Date of Patent: June 5, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yoshinaga, Takayuki Yoshii, Kohji Kamiya, Masanao Ehara
  • Publication number: 20120051766
    Abstract: A fixing device includes a fixing rotation body heating and fixing an unfixed image onto a recording medium; a pressing rotation body pressing the recording medium to the fixing rotation body; a first temperature detection unit detecting a temperature of the fixing rotation body; and plural second temperature detection units detecting a temperature of the pressing rotation body. Further the fixing device selects a predetermined second temperature detection unit from the plural second temperature detection units depending on an operation mode of the fixing device, and the fixing device detects the temperature of the pressing rotation body by using the predetermined second temperature detection unit selected by the fixing device.
    Type: Application
    Filed: August 30, 2011
    Publication date: March 1, 2012
    Inventors: Satoshi UENO, Masanao EHARA, Tadashi OGAWA, Teppei KAWATA, Takamasa HASE, Kazuya SAITO, Shuutaroh YUASA, Kensuke YAMAJI
  • Publication number: 20120045226
    Abstract: A fixing device includes a fixing rotation body heating and fixing an unfixed image onto a recording medium; a pressing rotation body pressing the recording medium to the fixing rotation body; and a temperature detection unit detecting a temperature of the pressing rotation body. Further, when a predetermined time period elapses since a warm-up operation has started before a temperature detected by the temperature detection unit is equal to or greater than a predetermined temperature or when the temperature detected by the temperature detection unit is equal to or greater than the predetermined temperature before the predetermined time period elapses since a warm-up operation has started, the fixing device determines that the warm-up operation is finished.
    Type: Application
    Filed: August 18, 2011
    Publication date: February 23, 2012
    Inventors: Takamasa HASE, Masanao Ehara, Tadashi Ogawa, Takeshi Uchitani, Satoshi Ueno, Teppei Kawata, Kazuya Saito, Shuutaroh Yuasa, Kensuke Yamaji
  • Publication number: 20110311284
    Abstract: A fixing device includes a fixing rotary body to rotate in a predetermined direction of rotation and a pressing rotary body pressed against the fixing rotary body to rotate in a direction counter to the direction of rotation of the fixing rotary body and form a nip therebetween through which a recording medium bearing a toner image passes. A heat generator is disposed opposite the fixing rotary body at a section other than the nip to heat the fixing rotary body. A moving assembly is disposed opposite the heat generator to generate a magnetic force to move the heat generator with respect to the fixing rotary body so as to change one of a pressure and a distance between the heat generator and the fixing rotary body.
    Type: Application
    Filed: June 16, 2011
    Publication date: December 22, 2011
    Inventors: Hiroshi Seo, Masanao Ehara, Tadashi Ogawa, Satoshi Ueno, Shuutaroh Yuasa
  • Publication number: 20110229162
    Abstract: A fixing device includes a fixing member, an induction heating unit, a pressing member, and a damage detection unit. The fixing member heats a toner image on a recording medium to fix the toner image onto the recording medium. The induction heating unit heats the fixing member by electromagnetic induction. The pressing member presses the fixing member to form a fixing nip portion. The fixing member includes a heat insulating elastic layer and a sleeve layer. The sleeve layer is located outside the heat insulating elastic layer and is provided with an outer conductive layer that generates heat from a magnetic flux generated by the induction heating unit. The damage detection unit is connected to the outer, conductive layer.
    Type: Application
    Filed: March 10, 2011
    Publication date: September 22, 2011
    Applicant: Ricoh Company, Limited
    Inventors: Tadashi Ogawa, Masanao Ehara, Satoshi Ueno, Hiroshi Seo, Takamasa Hase, Shuutaroh Yuasa
  • Publication number: 20110229178
    Abstract: A fixing unit includes a fixing member to fuse a toner image on a recording medium on the recording medium; a pressure member to press against the fixing member to define a first nip between the fixing member and the pressure member through which the recording medium is transported; a shifting unit to move the pressure member relative to the fixing member to increase or decrease a pressure of the first nip; a curling correction unit disposed downstream from the first nip in a transport direction of the recording medium that imparts a second curling direction to the recording medium; and a variable setting unit operatively connected to the curling correction unit to variably set an amount of the second curling direction to the recording medium by the curling correction unit depending on the first nip pressure increased or decreased by the shifting unit.
    Type: Application
    Filed: March 7, 2011
    Publication date: September 22, 2011
    Inventors: Tadashi OGAWA, Masanao EHARA, Satoshi UENO, Hiroshi SEO, Takahiro IMADA, Takamasa HASE
  • Publication number: 20110229236
    Abstract: A fixing device in an image forming apparatus includes a conveyance member to convey a recording medium at a fixing nip where an image carried on the recording medium is fixed onto it; a plurality of temperature detectors to detect temperature of the conveyance member, the detectors being disposed at both end portions of the conveyance member outside an area where a maximum-sided recording medium passes through; a guide member to guide the recording medium toward the fixing nip; and a guide plate displacing unit to displace a part of the guide member in a direction orthogonal to a conveyed surface of the recording medium to be conveyed at the fixing nip, based on temperature difference detected by the plurality of temperature detectors.
    Type: Application
    Filed: March 16, 2011
    Publication date: September 22, 2011
    Inventors: Masanao Ehara, Tadashi Ogawa, Satoshi Ueno, Hiroshi Seo, Shuutaroh Yuasa
  • Publication number: 20110229161
    Abstract: A thermal fixing device includes a fixing member, a flexible endless belt, a flexible endless belt, a rotary pressure member, a heating unit, and a rotation detector. The flexible endless belt is disposed on an outer circumferential surface of the fixing member. The rotary pressure member is disposed parallel to and pressing against the fixing member via the endless belt. The heating unit heats the endless belt. The rotation detector detects a rotation speed of the endless belt. The heating unit is powered off when the rotation speed of the endless belt detected by the rotation detector is at or below a predetermined threshold value.
    Type: Application
    Filed: March 16, 2011
    Publication date: September 22, 2011
    Inventors: Satoshi UENO, Masanao EHARA, Tadashi OGAWA, Hiroshi SEO, Takamasa HASE, Shuutaroh YUASA
  • Patent number: 8023861
    Abstract: A fixing device and image-forming apparatus, which provide required glossiness and paper adaptability, and, in addition, feature good operability and excellent durability while achieving optimal pressure-applying force for a variety of requirements. The fixing device has a pressure-applying lever; a pressure-releasing lever; a locking member, the one end of which is rotationally attached to the pressure-releasing lever; and an elastic member which pulls the locking member in a locking direction. The configuration is such that the rotation of the pressure-releasing lever displaces the location of the locking member, thereby enabling switching between a pressure-applying position, in which a fixing member presses against another fixing member, and a pressure-releasing position, in which the one fixing member moves away from the other fixing member.
    Type: Grant
    Filed: December 2, 2008
    Date of Patent: September 20, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yoshinaga, Masanao Ehara, Akira Shinshi, Naoki Iwaya, Yoshiki Yamaguchi
  • Publication number: 20110222876
    Abstract: A fixing device includes a fixing member, a pressure member, and a damage detecting unit. The fixing member includes a heat-insulating elastic layer, to which a conductive thin-film layer is provided. The pressure member presses against the fixing member to form a fixing nip. The damage detecting unit detects the electric resistance of the thin-film layer. The damage detecting unit detects a change in the electric resistance of the thin-film layer, thereby detecting damage to the fixing member. Depending on the extent of the damage, the condition of conveyance of a recording medium to the fixing nip is changed.
    Type: Application
    Filed: March 8, 2011
    Publication date: September 15, 2011
    Applicant: Ricoh Company, Limited
    Inventors: Shuutaroh Yuasa, Masanao Ehara, Tadashi Ogawa, Satoshi Ueno, Hiroshi Seo, Takamasa Hase
  • Publication number: 20110222926
    Abstract: A fixing device includes an image surface side separating member that separates a recording medium from a fixing member; an image surface side conveyance guiding member arranged downstream of the image surface side separating member; a non-image surface side separating member that separates the recording medium from a pressing member; and a non-image surface side conveyance guiding member arranged downstream of the non-image surface side separating member. When the image surface side conveyance guiding member is rotated about its rotation axis so as to be opened or closed, the image surface side separating member is also rotated or slid so as to be opened or closed simultaneously. When the non-image surface side conveyance guiding member is rotated about its rotation axis so as to be opened or closed, the non-image surface side separating member is also rotated or slid so as to be opened or closed simultaneously.
    Type: Application
    Filed: March 7, 2011
    Publication date: September 15, 2011
    Applicant: Ricoh Company, Limited
    Inventors: Satoshi Ueno, Masanao Ehara, Tadashi Ogawa, Hiroshi Seo, Takamasa Hase, Takahiro Imada, Shuutaro Yuasa
  • Publication number: 20110150518
    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: Application
    Filed: December 21, 2010
    Publication date: June 23, 2011
    Inventors: Takamasa HASE, Masanao Ehara, Kenji Ishii, Tadashi Ogawa, Satoshi Ueno, Hiroshi Seo, Takahiro Imada, Shuutaroh Yuasa
  • Publication number: 20110064502
    Abstract: A fixing system includes a fixing device that fixes a non-fixed image with heat onto a recording medium. The fixing device includes a fixing roller that generates heat and a pressing roller that presses against the fixing roller. A curl correction device is provided to correct curling of the recording medium passing through the fixing device. The curl correction device includes a heating roller unit that generates heat and an elastic roller that presses against the heating roller unit. A magnetic flux generating device is arranged in the vicinity of the fixing device and the curl correction device and generates magnetic flux.
    Type: Application
    Filed: September 14, 2010
    Publication date: March 17, 2011
    Inventors: Takamasa HASE, Masanao EHARA, Kenji ISHI, Tadashi OGAWA, Satoshi UENO, Hiroshi SEO, Takahiro IMADA
  • Publication number: 20110064490
    Abstract: An elastic layer is provided on a surface of one of a metal core and a substrate. A fixing member and a pressure member press into each other and collectively create a nip therebetween. A toner image is conveyed and fixed when passing through the nip. A thickness of the elastic layer is different in at least two widthwise regions by the same amount from the other region. A pair of edges of a prescribed size of the transfer sheet pass through these two widthwise regions, respectively.
    Type: Application
    Filed: September 13, 2010
    Publication date: March 17, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Takahiro Imada, Masanao Ehara, Tadashi Ogawa, Satoshi Ueno, Hiroshi Seo, Takamasa Hase, Kenji Ishi
  • Publication number: 20110064451
    Abstract: A fixing device to fix a toner image on a sheet of recording media, the fixing device includes a fixing rotary member to heat the toner image on the sheet of the recording media, a pressure rotary member pressed against the fixing rotary member, a conveyance guide member arranged to a fixing nip at the upstream side of a conveyance direction of the sheet to support the sheet going to the fixing nip, a scraper arranged to the conveyance guide member at the opposite side on the basis of the conveyance direction. The end of the conveyance guide member contacts with the scraper, when the conveyance guide member turns on a rotary axis of the guide member.
    Type: Application
    Filed: September 7, 2010
    Publication date: March 17, 2011
    Inventors: Yoshiki YAMAGUCHI, Masanao Ehara, Naoki Iwaya, Yutaka Ikebuchi
  • Publication number: 20110064450
    Abstract: A fixing device includes a heating source; a heating member heated by the heating source; a pressing member contacting the heating member to form a fixing nip therebetween, at which an unfixed image of toner on a recording sheet is fixed to the recording sheet; a first charging member located at an entrance of the fixing device, from which the recording sheet bearing the unfixed toner image enters the fixing device, so as to face the unfixed toner image. The first charging member is not contacted with the heating member and pressing member, and has a charge with a polarity opposite to a polarity of a charge of the toner to collect floating particles of the toner.
    Type: Application
    Filed: August 30, 2010
    Publication date: March 17, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Kenji Ishii, Tadashi Ogawa, Satoshi Ueno, Hiroshi Seo, Masanao Ehara