Patents by Inventor Toshiaki Higaya

Toshiaki Higaya 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: 8112023
    Abstract: An image forming apparatus includes an image carrier to carry a toner image and a fixing device to fix the toner image transferred from the image carrier onto a recording medium by applying at least heat to at least one of the toner image and the recording medium. Such a fixing device includes: a magnetic flux generator to generate a magnetic flux; and a heat generating member disposed at least partially in the magnetic flux. The heat generating member includes a heat generating layer to generate heat via eddy currents therein induced by the magnetic flux, magnitudes of the eddy currents varying according to positions thereof in a width direction of the heat generating layer. Included within the heat generating layer is a magnetic layer having a Curie point in a range, e.g., from about 100 degrees centigrade to about 300 degrees centigrade.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: February 7, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Seo, Akiko Ito, Tadashi Ogawa, Toshiaki Higaya
  • Publication number: 20110091253
    Abstract: An image forming apparatus includes an image carrier to carry a toner image and a fixing device to fix the toner image transferred from the image carrier onto a recording medium by applying at least heat to at least one of the toner image and the recording medium. Such a fixing device includes: a magnetic flux generator to generate a magnetic flux; and a heat generating member disposed at least partially in the magnetic flux. The heat generating member includes a heat generating layer to generate heat via eddy currents therein induced by the magnetic flux, magnitudes of the eddy currents varying according to positions thereof in a width direction of the heat generating layer. Included within the heat generating layer is a magnetic layer having a Curie point in a range, e.g., from about 100 degrees centigrade to about 300 degrees centigrade.
    Type: Application
    Filed: December 21, 2010
    Publication date: April 21, 2011
    Inventors: Hiroshi Seo, Akiko Ito, Tadashi Ogawa, Toshiaki Higaya
  • Patent number: 7885590
    Abstract: An image forming apparatus includes an image carrier to carry a toner image and a fixing device to fix the toner image transferred from the image carrier onto a recording medium by applying at least heat to at least one of the toner image and the recording medium. Such a fixing device includes: a magnetic flux generator to generate a magnetic flux; and a heat generating member disposed at least partially in the magnetic flux. The heat generating member includes a heat generating layer to generate heat via eddy currents therein induced by the magnetic flux, magnitudes of the eddy currents varying according to positions thereof in a width direction of the heat generating layer. Included within the heat generating layer is a magnetic layer having a Curie point in a range, e.g., from about 100 degrees centigrade to about 300 degrees centigrade.
    Type: Grant
    Filed: April 17, 2007
    Date of Patent: February 8, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Seo, Akiko Ito, Tadashi Ogawa, Toshiaki Higaya
  • Patent number: 7817952
    Abstract: A fixer configured to fix an image on an recording medium passing through a fixing nip includes a holder including an elastic layer, a fixing rotator including a heating layer, provided overlying the holder, and a pressurizer configured to pressurize the holder via the fixing rotator to form the fixing nip. A part of the pressurizer, which forms the fixing nip, has a length not less than a length of the heating layer in a width direction perpendicular to a conveyance direction of the recording medium.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: October 19, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Seo, Akiko Ito, Tadashi Ogawa, Toshiaki Higaya
  • Patent number: 7512371
    Abstract: An image forming apparatus includes a fixing unit for fixing a toner image on a recording sheet. In the fixing unit, a magnetic flux generator generates magnetic flux to induce heat in a fixing roller. The recording sheet having the toner image is inserted between the fixing roller and a pressure roller pressingly contacting the fixing roller. The fixing roller applies heat to the recording sheet. The pressure roller applies pressure to the recording sheet. The heat and pressure fix the toner image on the recording sheet. The magnetic flux generator is disposed to face outer and inner circumferential surfaces of the fixing roller. The magnetic flux generator is formed in a U-like or loop-like shape, and the fixing roller is placed in a gap or a loop of the magnetic flux generator. The magnetic flux generator may include a single wire.
    Type: Grant
    Filed: September 12, 2005
    Date of Patent: March 31, 2009
    Assignee: Ricoh Company, Ltd.
    Inventor: Toshiaki Higaya
  • Publication number: 20070280754
    Abstract: A fixing device includes a fixing sleeve, a cylindrical fixing roller, and a pressure roller. The fixing sleeve includes a heating layer that generates heat to fuse and fix toner. The fixing roller has a surface covered with the fixing sleeve. The pressure roller presses the fixing roller via the fixing sleeve to form a nip portion. The fixing sleeve is freely rotatable with respect to the fixing roller, and is slid for rotation.
    Type: Application
    Filed: June 4, 2007
    Publication date: December 6, 2007
    Inventors: Tadashi Ogawa, Toshiaki Higaya, Hiroshi Seo, Akiko Ito
  • Publication number: 20070242988
    Abstract: An image forming apparatus includes an image carrier to carry a toner image and a fixing device to fix the toner image transferred from the image carrier onto a recording medium by applying at least heat to at least one of the toner image and the recording medium. Such a fixing device includes: a magnetic flux generator to generate a magnetic flux; and a heat generating member disposed at least partially in the magnetic flux. The heat generating member includes a heat generating layer to generate heat via eddy currents therein induced by the magnetic flux, magnitudes of the eddy currents varying according to positions thereof in a width direction of the heat generating layer. Included within the heat generating layer is a magnetic layer having a Curie point in a range, e.g., from about 100 degrees centigrade to about 300 degrees centigrade.
    Type: Application
    Filed: April 17, 2007
    Publication date: October 18, 2007
    Inventors: Hiroshi Seo, Akiko Ito, Tadashi Ogawa, Toshiaki Higaya
  • Publication number: 20070212089
    Abstract: A fixer configured to fix an image on an recording medium passing through a fixing nip includes a holder including an elastic layer, a fixing rotator including a heating layer, provided overlying the holder, and a pressurizer configured to pressurize the holder via the fixing rotator to form the fixing nip. A part of the pressurizer, which forms the fixing nip, has a length not less than a length of the heating layer in a width direction perpendicular to a conveyance direction of the recording medium.
    Type: Application
    Filed: March 13, 2007
    Publication date: September 13, 2007
    Inventors: Hiroshi Seo, Akiko Ito, Tadashi Ogawa, Toshiaki Higaya
  • Patent number: 7150954
    Abstract: An image forming method, comprising passing a toner image-bearing sheet through a nip defined between two rollers including a heater roller to fix the toner image on the sheet, wherein the toner image is formed from a toner comprising a binder resin, and a colorant, wherein the toner image before the passage through the nip has a toner volume V1 and a toner image area S1, wherein the toner image after the passage through the nip has a toner volume V2 and a toner image area S2, and wherein a volume change Vt and an area change St defined by the formulas shown below are 30% or less and 20% or less, respectively: Vt(%)=(V1?V2)/V1×100 St(%)=(S2?S1)/S1×100. Alternatively, the toner image before the passage through the nip has a surface roughness of 2.5 ?m or less.
    Type: Grant
    Filed: December 3, 2004
    Date of Patent: December 19, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuo Aoki, Kumi Hasegawa, Toshiaki Higaya, Yasushi Koichi, Yutaka Takahashi, Tadashi Kasai
  • Patent number: 7135660
    Abstract: An induction heating type fixing device for an electrophotographic image forming apparatus is disclosed. An inducting heating coil has a plurality of bobbins each having a particular diameter and assembled in a telescopic manner. A particular conductor is wound round each bobbin beforehand with leads being laid inside of the conductor. The bobbin may be implemented as a plurality of bobbin members removably connected together.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: November 14, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Akiko Miyahara, Toshiaki Higaya, Masae Sugawara, Tomotaka Takamura
  • Publication number: 20060056889
    Abstract: An image forming apparatus includes a fixing unit for fixing a toner image on a recording sheet. In the fixing unit, a magnetic flux generator generates magnetic flux to induce heat in a fixing roller. The recording sheet having the toner image is inserted between the fixing roller and a pressure roller pressingly contacting the fixing roller. The fixing roller applies heat to the recording sheet. The pressure roller applies pressure to the recording sheet. The heat and pressure fix the toner image on the recording sheet. The magnetic flux generator is disposed to face outer and inner circumferential surfaces of the fixing roller. The magnetic flux generator is formed in a U-like or loop-like shape, and the fixing roller is placed in a gap or a loop of the magnetic flux generator. The magnetic flux generator may include a single wire.
    Type: Application
    Filed: September 12, 2005
    Publication date: March 16, 2006
    Inventor: Toshiaki Higaya
  • Publication number: 20050242084
    Abstract: An induction heating type fixing device for an electrophotographic image forming apparatus is disclosed. An inducting heating coil has a plurality of bobbins each having a particular diameter and assembled in a telescopic manner. A particular conductor is wound round each bobbin beforehand with leads being laid inside of the conductor. The bobbin may be implemented as a plurality of bobbin members removably connected together.
    Type: Application
    Filed: July 8, 2005
    Publication date: November 3, 2005
    Inventors: Akiko Miyahara, Toshiaki Higaya, Masae Sugawara, Tomotaka Takamura
  • Patent number: 6946629
    Abstract: An induction heating type fixing device for an electrophotographic image forming apparatus is disclosed. An inducting heating coil has a plurality of bobbins each having a particular diameter and assembled in a telescopic manner. A particular conductor is wound round each bobbin beforehand with leads being laid inside of the conductor. The bobbin may be implemented as a plurality of bobbin members removably connected together.
    Type: Grant
    Filed: March 29, 2004
    Date of Patent: September 20, 2005
    Assignees: Ricoh Company, Ltd., Tohoku Ricoh Co., Ltd.
    Inventors: Akiko Miyahara, Toshiaki Higaya, Masae Sugawara, Tomotaka Takamura
  • Patent number: 6899986
    Abstract: An image forming method, comprising passing a toner image-bearing sheet through a nip defined between two rollers including a heater roller to fix the toner image on the sheet, wherein the toner image is formed from a toner comprising a binder resin, and a colorant, wherein the toner image before the passage through the nip has a toner volume V1 and a toner image area S1, wherein the toner image after the passage through the nip has a toner volume V2 and a toner image area S2, and wherein a volume change Vt and an area change St defined by the formulas shown below are 30% or less and 20% or less, respectively: Vt(%)=(V1?V2)/V1×100 St(%)=(S2?S2)/S1×100. Alternatively, the toner image before the passage through the nip has a surface roughness of 2.5 ?m or less.
    Type: Grant
    Filed: September 23, 2002
    Date of Patent: May 31, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuo Aoki, Kumi Hasegawa, Toshiaki Higaya, Yasushi Koichi, Yutaka Takahashi, Tadashi Kasai
  • Publication number: 20050079430
    Abstract: An image forming method, comprising passing a toner image-bearing sheet through a nip defined between two rollers including a heater roller to fix the toner image on the sheet, wherein the toner image is formed from a toner comprising a binder resin, and a colorant, wherein the toner image before the passage through the nip has a toner volume V1 and a toner image area S1, wherein the toner image after the passage through the nip has a toner volume V2 and a toner image area S2, and wherein a volume change Vt and an area change St defined by the formulas shown below are 30% or less and 20% or less, respectively: Vt(%)=(V1?V2)/V1×100 St(%)=(S2?S1)/S1×100. Alternatively, the toner image before the passage through the nip has a surface roughness of 2.5 ?m or less.
    Type: Application
    Filed: December 3, 2004
    Publication date: April 14, 2005
    Inventors: Mitsuo Aoki, Kumi Hasegawa, Toshiaki Higaya, Yasushi Koichi, Yutaka Takahashi, Tadashi Kasai
  • Publication number: 20040188423
    Abstract: An induction heating type fixing device for an electrophotographic image forming apparatus is disclosed. An inducting heating coil has a plurality of bobbins each having a particular diameter and assembled in a telescopic manner. A particular conductor is wound round each bobbin beforehand with leads being laid inside of the conductor. The bobbin may be implemented as a plurality of bobbin members removably connected together.
    Type: Application
    Filed: March 29, 2004
    Publication date: September 30, 2004
    Inventors: Akiko Miyahara, Toshiaki Higaya, Masae Sugawara, Tomotaka Takamura
  • Patent number: 6753515
    Abstract: An induction heating type fixing device for an electrophotographic image forming apparatus is disclosed. An inducting heating coil has a plurality of bobbins each having a particular diameter and assembled in a telescopic manner. A particular conductor is wound round each bobbin beforehand with leads being laid inside of the conductor. The bobbin may be implemented as a plurality of bobbin members removably connected together.
    Type: Grant
    Filed: April 27, 2001
    Date of Patent: June 22, 2004
    Assignees: Ricoh Company, Ltd., Tohoku Ricoh Co., Ltd.
    Inventors: Akiko Miyahara, Toshiaki Higaya, Masae Sugawara, Tomotaka Takamura
  • Publication number: 20030186155
    Abstract: An image forming method, comprising passing a toner image-bearing sheet through a nip defined between two rollers including a heater roller to fix the toner image on the sheet, wherein the toner image is formed from a toner comprising a binder resin, and a colorant, wherein the toner image before the passage through the nip has a toner volume V1 and a toner image area S1, wherein the toner image after the passage through the nip has a toner volume V2 and a toner image area S2, and wherein a volume change Vt and an area change St defined by the formulas shown below are 30% or less and 20% or less, respectively:
    Type: Application
    Filed: September 23, 2002
    Publication date: October 2, 2003
    Inventors: Mitsuo Aoki, Kumi Hasegawa, Toshiaki Higaya, Yasushi Koichi, Yutaka Takahashi, Tadashi Kasai
  • Patent number: 6574448
    Abstract: An image forming apparatus includes a first image bearing member, a second image bearing member, and a fixing device. A first visual image formed on the first image bearing member is transferred onto the second image bearing member to be transferred from the second image bearing member onto a first side of a recording medium, and a second visual image formed on the first bearing member is transferred from the first image bearing member onto a second side of the recording medium, so that the visual images are obtained on the first and second sides of the recording medium respectively. The visual images on the first and second sides of the recording medium are fixed by the fixing device in a state that the second image bearing member and the recording medium are overlapped with each other.
    Type: Grant
    Filed: June 11, 2001
    Date of Patent: June 3, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Hideaki Mochimaru, Yasukuni Omata, Norimasa Sohmiya, Mitsuru Seto, Toshiaki Higaya, Masanori Matsuda
  • Publication number: 20020031381
    Abstract: An induction heating type fixing device for an electrophotographic image forming apparatus is disclosed. An inducting heating coil has a plurality of bobbins each having a particular diameter and assembled in a telescopic manner. A particular conductor is wound round each bobbin beforehand with leads being laid inside of the conductor. The bobbin may be implemented as a plurality of bobbin members removably connected together.
    Type: Application
    Filed: April 27, 2001
    Publication date: March 14, 2002
    Applicant: Ricoh Company, Ltd.
    Inventors: Akiko Miyahara, Toshiaki Higaya, Masae Sugawara, Tomotaka Takamura