Patents by Inventor Yasunobu Ogata

Yasunobu Ogata 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).

  • Publication number: 20130257573
    Abstract: The present invention relates to ferromagnetic particles comprising an Fe16N2 compound phase in an amount of not less than 70% as measured by Mössbauer spectrum, and at least one metal element X selected from the group consisting of Mn, Ni, Ti, Ga, Al, Ge, Zn, Pt and Si in such an amount that a molar ratio of the metal element X to Fe is 0.04 to 25%, the ferromagnetic particles having a BHmax value of not less than 5 MGOe, and a process for producing the ferromagnetic particles, and further relates to an anisotropic magnet or a bonded magnet which is obtained by magnetically orienting the ferromagnetic particles. The ferromagnetic particles according to the present invention can be produced in an industrial scale and are in the form of Fe16N2 particles comprising different kinds of metal elements having a large BHmax value.
    Type: Application
    Filed: September 22, 2011
    Publication date: October 3, 2013
    Applicants: TOHOKU UNIVERSITY, TODA KOGYO CORPORATION
    Inventors: Migaku Takahashi, Tomoyuki Ogawa, Yasunobu Ogata, Akimasa Sakuma, Naoya Kobayashi, Chammika Ruwan Polwatta Gallage, Kaori Kohara
  • Publication number: 20120244356
    Abstract: The present invention relates to Fe16N2 particles in the form of a single phase which are obtained by subjecting iron oxide or iron oxyhydroxide whose surface may be coated with at least alumina or silica, if required, as a starting material, to reducing treatment and nitridation treatment, a process for producing the Fe16N2 particles in the form of a single phase for a heat treatment time of not more than 36 hr, and further relates to an anisotropic magnet or a bonded magnet which is obtained by magnetically orienting the Fe16N2 particles in the form of a single phase. The Fe16N2 particles according to the present invention can be produced in an industrial scale and have a large BHmax value.
    Type: Application
    Filed: October 19, 2010
    Publication date: September 27, 2012
    Inventors: Migaku Takahashi, Tomoyuki Ogawa, Yasunobu Ogata, Naoya Kobayashi
  • Patent number: 8206606
    Abstract: An oxide magnetic material includes a ferrite with a hexagonal structure as its main phase. Metallic elements included in the oxide magnetic material are represented by the formula: Ca1-x-x?LaxSrx?Fe2n-yCoy, where atomic ratios x, x? and y and a molar ratio n satisfy 0.4?x?0.6, 0.01?x??0.3, 0.2?y?0.45 and 5.2?n?5.8, respectively.
    Type: Grant
    Filed: June 25, 2008
    Date of Patent: June 26, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Seiichi Hosokawa, Yoshinori Kobayashi, Yasunobu Ogata, Etsushi Oda
  • Patent number: 7970312
    Abstract: An image forming apparatus includes a main body, an openable/closable cover panel, a unitary assembly, a holder, and a fastener. The openable/closable cover panel covers an opening in the main body. The unitary assembly is detachably attached to an inner side of the cover panel. The fastener fastens the assembly in place on the cover panel. The holder includes a positioning surface and first and second guide surfaces to hold the assembly on the cover panel. The positioning surface receives a positioning pin projecting from the assembly. The first and second guide surfaces are disposed on opposite sides of the positioning surface, and each guide surface slidably guides the positioning pin onto the positioning surface. The second guide surface is elastically displaceable to cause the positioning pin to slide off onto the positioning surface as the positioning pin presses against the second guide surface.
    Type: Grant
    Filed: October 28, 2009
    Date of Patent: June 28, 2011
    Assignee: Ricoh Company Limited
    Inventor: Yasunobu Ogata
  • Patent number: 7962079
    Abstract: A disclosed fixing device includes a fixing member configured to heat and melt a toner image to fix it onto a recording medium; a pressure member abutting the fixing member to form a nip into which the recording medium is fed; a separating member disposed on the downstream side in the moving direction of the fixing member in relation to the nip in a manner to oppose the fixing member, and configured to perform a separating operation to prevent the recording medium from winding around the fixing member; an electrically grounded frame supporting the fixing member, the pressure member and the separating member; and a conductive member inserted between a supporting portion of the frame and a supported portion of the separating member and having a higher electric resistance than the frame. The separating member and the frame are rendered electrically conductive to each other only via the conductive member.
    Type: Grant
    Filed: October 7, 2008
    Date of Patent: June 14, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Yasunobu Ogata
  • Patent number: 7906036
    Abstract: A sintered ferrite magnet having a basic composition represented by the general formula: A1?x?y+aCax+bRy+cFe2n?zCoz+dO19 (atomic ratio), wherein a, b, c and d represent the amounts of an A element, Ca, an R element and Co added in the pulverization step of an oxide magnet material, which are numerals meeting the conditions of 0.03?x?0.4, 0.1?y?0.6, 0?z?0.4, 4?n?10, x+y<1, 0.03?x+b?0.4, 0.1?y+c?0.6, 0.1?z+d?0.4, 0.50?[(1?x?y+a)/(1?y+a+b)]?0.97, 1.1?(y+c)/(z+d)?1.8, 1.0?(y+c)/x?20, and 0.1?x/(z+d)?1.2.
    Type: Grant
    Filed: September 13, 2004
    Date of Patent: March 15, 2011
    Assignee: Neomax Co., Ltd.
    Inventors: Takashi Takami, Yasunobu Ogata
  • Patent number: 7881635
    Abstract: An intermediate transfer unit can be detached from a device main body through an opening that is covered by an openable and closable front cover. A sheet path is provided between the intermediate transfer unit and the front cover. A portion of a convey-guiding unit of the sheet path falls in the way when detaching the detachable intermediate transfer unit. The portion of the convey-guiding unit, which falls in the way when detaching the detachable intermediate transfer unit, is formed as a detachable convey-guiding member that is detachably attached to the device main body.
    Type: Grant
    Filed: February 14, 2008
    Date of Patent: February 1, 2011
    Assignee: Ricoh Company, Limited
    Inventors: Yoshikazu Yamazoe, Yutaka Naito, Yasunobu Ogata, Shin Yamamoto
  • Publication number: 20100124028
    Abstract: An image forming apparatus includes a main body, an openable/closable cover panel, a unitary assembly, a holder, and a fastener. The openable/closable cover panel covers an opening in the main body. The unitary assembly is detachably attached to an inner side of the cover panel. The fastener fastens the assembly in place on the cover panel. The holder includes a positioning surface and first and second guide surfaces to hold the assembly on the cover panel. The positioning surface receives a positioning pin projecting from the assembly. The first and second guide surfaces are disposed on opposite sides of the positioning surface, and each guide surface slidably guides the positioning pin onto the positioning surface. The second guide surface is elastically displaceable to cause the positioning pin to slide off onto the positioning surface as the positioning pin presses against the second guide surface.
    Type: Application
    Filed: October 28, 2009
    Publication date: May 20, 2010
    Inventor: Yasunobu OGATA
  • Publication number: 20090261288
    Abstract: An oxide magnetic material includes a ferrite with a hexagonal structure as its main phase. Metallic elements included in the oxide magnetic material are represented by the formula: Ca1-x-x?LaxSrx?Fe2n-yCoy, where atomic ratios x, x? and y and a molar ratio n satisfy 0.4?x?0.6, 0.01?x??0.3, 0.2?y?0.45 and 5.2?n?5.8, respectively.
    Type: Application
    Filed: June 25, 2008
    Publication date: October 22, 2009
    Applicant: HITACHI METALS, LTD.
    Inventors: Seiichi Hosokawa, Yoshinori Kobayashi, Yasunobu Ogata, Etsushi Oda
  • Publication number: 20090110452
    Abstract: A disclosed fixing device includes a fixing member configured to heat and melt a toner image to fix it onto a recording medium; a pressure member abutting the fixing member to form a nip into which the recording medium is fed; a separating member disposed on the downstream side in the moving direction of the fixing member in relation to the nip in a manner to oppose the fixing member, and configured to perform a separating operation to prevent the recording medium from winding around the fixing member; an electrically grounded frame supporting the fixing member, the pressure member and the separating member; and a conductive member inserted between a supporting portion of the frame and a supported portion of the separating member and having a higher electric resistance than the frame. The separating member and the frame are rendered electrically conductive to each other only via the conductive member.
    Type: Application
    Filed: October 7, 2008
    Publication date: April 30, 2009
    Inventor: Yasunobu OGATA
  • Publication number: 20080193162
    Abstract: An intermediate transfer unit can be detached from a device main body through an opening that is covered by an openable and closable front cover. A sheet path is provided between the intermediate transfer unit and the front cover. A portion of a convey-guiding unit of the sheet path falls in the way when detaching the detachable intermediate transfer unit. The portion of the convey-guiding unit, which falls in the way when detaching the detachable intermediate transfer unit, is formed as a detachable convey-guiding member that is detachably attached to the device main body.
    Type: Application
    Filed: February 14, 2008
    Publication date: August 14, 2008
    Inventors: Yoshikazu Yamazoe, Yutaka Naito, Yasunobu Ogata, Shin Yamamoto
  • Patent number: 7169319
    Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1?xRx)O.n[(Fe1?yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01?x?0.4, [x/(2.6n)]?y?[x/(1.6n)], and 5?n?6, and substantially having a magnetoplumbite-type crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.
    Type: Grant
    Filed: October 14, 2004
    Date of Patent: January 30, 2007
    Assignee: Neomax Co., Ltd.
    Inventors: Takashi Takami, Yutaka Kubota, Yasunobu Ogata
  • Publication number: 20060284136
    Abstract: A sintered ferrite magnet having a basic composition represented by the general formula: A1?x?y+aCax+bRy+cFe2n?zCoz+dO19 (atomic ratio), wherein a, b, c and d represent the amounts of an A element, Ca, an R element and Co added in the pulverization step of an oxide magnet material, which are numerals meeting the conditions of 0.03?x?0.4, 0.1?y?0.6, 0?z?0.4, 4?n?10, x+y?1, 0.03?x+b?0.4, 0.1?y+c?0.6, 0.1?z+d?0.4, 0.50?[(1?x?y+a)/(1?y+a+b)]?0.97, 1.1?(y+c)/(z+d)?1.8, 1.0?(y+c)/x?20, and 0.1?x/(z+d)?1.2.
    Type: Application
    Filed: September 14, 2004
    Publication date: December 21, 2006
    Inventors: Takashi Takami, Yasunobu Ogata
  • Publication number: 20050098761
    Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1-xRx)O.n[(Fe1-yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01?x?0.4, [x/(2.6n)]?y?[x/(1.6n)], and 5?n?6, and substantially having a magnetoplumbite-type crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.
    Type: Application
    Filed: October 14, 2004
    Publication date: May 12, 2005
    Inventors: Takashi Takami, Yutaka Kubota, Yasunobu Ogata
  • Patent number: 6858156
    Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1?xRx)O.n[(Fe1?yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01?x?0.4, [x/(2.6n)]?y?[x/(1.6n)], and 5?n?6, and substantially having a magnetoplumbite crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.
    Type: Grant
    Filed: January 16, 2003
    Date of Patent: February 22, 2005
    Assignee: Hitachi Metals, Ltd.
    Inventors: Takashi Takami, Yutaka Kubota, Yasunobu Ogata
  • Patent number: 6737011
    Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1−xRx)O.n[(Fe1−yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01≦x≦0.4, [x/(2.6n)]≦y≦[x/(1.6n)], and 5≦n≦6, and substantially having a magnetoplumbite crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.
    Type: Grant
    Filed: November 9, 1999
    Date of Patent: May 18, 2004
    Assignee: Hitachi Metals, Ltd.
    Inventors: Takashi Takami, Yutaka Kubota, Yasunobu Ogata
  • Publication number: 20030168785
    Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1-xRx)O.n[(Fe1-yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01≦x≦0.4, [x/(2.6n)]≦y≦[x/(1.6n)], and 5≦n≦6, and substantially having a magnetoplumbite-type crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.
    Type: Application
    Filed: January 16, 2003
    Publication date: September 11, 2003
    Applicant: HITACHI METALS, LTD.
    Inventors: Takashi Takami, Yutaka Kubota, Yasunobu Ogata
  • Patent number: 6537463
    Abstract: A resin-bonded magnet composed substantially of (a) an R—T—N-based magnetic powder having a basic composition of R&agr;T100−&agr;−&bgr;N&bgr;, wherein R is at least one selected form the group consisting of rare earth elements including Y, T is Fe or Fe and Co, 5≦&agr;≦20, and 5≦&bgr;≦30, (b) a ferrite magnetic powder having a substantially magnetoplumbite-type crystal structure and a basic composition represented by (A1−xR′x) O[(Fe1−yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R′ is at least one selected from the group consisting of rare earth elements including Y, La being indispensable, M is Co or Co and Zn, 0.01≦x<0.4, 0.005≦y≦0.04, and 5.0≦n≦6.4, and (c) a binder. The ferrite magnet powder is preferably an anisotropic, granulated powder or an anisotropic, sintered ferrite magnet powder.
    Type: Grant
    Filed: December 11, 2000
    Date of Patent: March 25, 2003
    Assignee: Hitachi Metals, Ltd.
    Inventors: Katsunori Iwasaki, Masahiro Tobise, Yasunobu Ogata, Mikio Shindo, Hiroshi Okajima
  • Patent number: 6528159
    Abstract: A diamond sintered body tool (20) having superior adhesion resistance, chipping resistance and high strength includes a tool base material (22) including a diamond sintered body, and a surface layer (21) formed on a surface of the tool base material (22). The surface layer (21) includes at least one of silicon, a silicon oxide, a silicon carbide, a silicon nitride and a solid solution thereof. The tool base material (22) has an inner portion (22b) including a first content of an iron group metal, and a surface portion (22a) surrounding the inner portion (22b ) and including a second content of the iron group metal lower than the first content.
    Type: Grant
    Filed: September 1, 2000
    Date of Patent: March 4, 2003
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yasuyuki Kanada, Yoshihiro Kuroda, Noboru Yamazaki, Yasunobu Ogata, Kunihiro Tomita, Tetsuo Nakai, Makoto Abe
  • Publication number: 20020084001
    Abstract: A resin-bonded magnet composed substantially of (a) an R-T-N-based magnetic powder having a basic composition of R&agr;T100-&agr;-&bgr;N&bgr;, wherein R is at least one selected form the group consisting of rare earth elements including Y, T is Fe or Fe and Co, 5≦&agr;≦20, and 5≦&bgr;≦30, (b) a ferrite magnetic powder having a substantially magnetoplumbite-type crystal structure and a basic composition represented by (A1-xR′x)O[(Fe1-yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R′ is at least one selected from the group consisting of rare earth elements including Y, La being indispensable, M is Co or Co and Zn, 0.01≦x≦0.4, 0.005≦y≦0.04, and 5.0≦n≦6.4, and (c) a binder. The ferrite magnet powder is preferably an anisotropic, granulated powder or an anisotropic, sintered ferrite magnet powder.
    Type: Application
    Filed: December 11, 2000
    Publication date: July 4, 2002
    Inventors: Katsunori Iwasaki, Masahiro Tobise, Yasunobu Ogata, Mikio Shindo, Hiroshi Okajima