Patents by Inventor Masahiro Mita

Masahiro Mita 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: 8115479
    Abstract: A rotation-angle-detecting apparatus comprising a magnet rotor having 4 or more magnetic poles on the surface, and sensor device for detecting magnetic flux from the magnet rotor, and an electronic circuit for outputting a signal representing the rotation angle of the magnet rotor using pluralities of signals obtained from the sensor device, the sensor device having pluralities of spin-valve, giant-magnetoresistive devices for outputting two or more different phase signals from a rotating magnetic field near the rotating magnet, each spin-valve, giant-magnetoresistive device having a pinned layer and a free layer, the magnetization direction of the pinned layer being fixed, and the magnetization direction of the free layer rotating depending on a magnetic field direction, pluralities of the spin-valve, giant-magnetoresistive devices comprising a first spin-valve, giant-magnetoresistive device having a reference magnetic-field-sensing direction, and a second spin-valve, giant-magnetoresistive device having a m
    Type: Grant
    Filed: November 20, 2007
    Date of Patent: February 14, 2012
    Assignee: Hitachi Metals, Ltd.
    Inventors: Kyohei Aimuta, Osamu Shimoe, Masahiro Mita
  • Patent number: 8039998
    Abstract: A surface magnet type rotor and an inner magnet type rotor having good motor characteristics in which bonding strength is high between a magnet section and a soft magnetic yoke section, and structural reliability is high even in high speed use, and its producing method. The rotor comprises an anisotropic bond magnet section and a soft magnetic section wherein the anisotropic bond magnet section is preformed in magnetic field and then formed to be integrated with the soft magnetic section in nonmagnetic field. Subsequently, it is heat hardened to produce a surface magnet type rotor. Magnet units, each having a magnetic pole composed by bonding a pair of permanent magnets such that the directions of magnetization become symmetric with respect to the bonding surface, are linked such that magnetic poles of different polarities appear alternately on the magnetic action surface thus forming an anisotropic magnet body.
    Type: Grant
    Filed: December 19, 2005
    Date of Patent: October 18, 2011
    Assignee: Hitachi Metals, Ltd.
    Inventors: Masahiro Masuzawa, Masahiro Mita, Keiko Kikuti
  • Patent number: 8015500
    Abstract: When a digital camera is set to retrieval mode, a map-style retrieval screen having a matrix structure is displayed on a display device. The digital camera searches for images photographed in the regions corresponding to each cell in the matrix structure, based on shooting location information appended to the images. The number of found images is displayed within each cell. When the user inputs a zoom in or zoom out command, the regions corresponding to each cell are made smaller or larger, according to the command. At the same time, a new retrieval is performed for images photographed in the regions corresponding to each of the modified cells. The number displayed within each cell is updated according to the number of images found in the new retrieval. When a single cell is selected, a list view of the images photographed in the region corresponding to the selected cell is displayed.
    Type: Grant
    Filed: December 14, 2007
    Date of Patent: September 6, 2011
    Assignee: Casio Computer Co., Ltd.
    Inventor: Masahiro Mita
  • Patent number: 7981359
    Abstract: A rotor comprising bonded magnet portions mainly composed of magnet powder and a binder, which are embedded in a soft magnetic portion mainly composed of soft magnetic powder and a binder, the rotor being produced by a compression-molding method, and the magnetic pole surfaces of the bonded magnet portions being embedded in the soft magnetic portion.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: July 19, 2011
    Assignee: Hitachi Metals, Ltd.
    Inventors: Masahiro Masuzawa, Shigeho Tanigawa, Masahiro Mita, Keiko Kikuchi
  • Patent number: 7906881
    Abstract: It is desired to design a coreless motor in which a gap size is set to be as small as possible, and a magnet having a large energy product is used in order to increase the gap magnetic flux density since the coreless motor has no iron core so that the magnetic flux density is small in the gap part. A rotor core of the motor has a permanent magnet rotor which is formed by a compression molding means, and which is formed of a compact formed by molding a powder material, the compact comprising a bond magnetic portion mainly composed of a binder and a magnetic powder, and a soft magnetic portion mainly composed of a binder and a soft magnetic powder, the bond magnetic portion having magnetic poles having at least one surface which is mechanically bonded to the soft magnetic portion, in order to solve the inherent problems.
    Type: Grant
    Filed: May 9, 2006
    Date of Patent: March 15, 2011
    Assignees: Hitachi, Ltd., Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Metals, Ltd.
    Inventors: Yuji Enomoto, Motoya Ito, Ryoso Masaki, Koichiro Ohara, Masahiro Mita, Matahiro Komuro, Masahiro Masuzawa
  • Publication number: 20100321008
    Abstract: An apparatus for detecting a rotation angle using a magnet rotor comprising a magnet having 2N poles, wherein N is a natural number, and a sensor device for detecting the direction of a magnetic flux from the magnet rotor, at least one of two output voltages obtained in radial and rotational directions by the sensor device being multiplied by a correction coefficient, and the rotation angle being calculated from the two corrected output voltages to increase the detection accuracy of the rotation angle.
    Type: Application
    Filed: February 3, 2009
    Publication date: December 23, 2010
    Applicant: Hitachi Metals, Ltd.
    Inventors: Masahiro Mita, Kyohei Aimuta, Osamu Shimoe, Rihito Kagawa
  • Patent number: 7847460
    Abstract: This invention provides a soft magnetic yoke-integrated bonded magnet in which a soft magnetic yoke has been integrally compression molded in such a state that the soft magnetic yoke is engaged in a joined face formed by bringing a binding material-containing magnetic powder into contact with a binding material-containing soft magnetic powder. The soft magnetic yoke part and the bonded magnetic part are constructed so that, when the soft magnetic yoke part and the bonded magnet part are compression molded separately from each other, the spring back level is identical upon the release of the compression force.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: December 7, 2010
    Assignee: Hitachi Metals, Ltd.
    Inventors: Masahiro Masuzawa, Masahiro Mita, Shigeho Tanigawa, Kyohei Aimuta
  • Publication number: 20100047111
    Abstract: Disclosed are: a magnetic shielding material having excellent magnetic shielding property at a low magnetic field; and a magnetic shielding component and a magnetic shielding room each using the magnetic shielding material. Specifically disclosed is a magnetic shielding material comprising the following components (by mass): Ni: 70.0-85.0%, Cu: 0.6% or less, Mo: 10.0% or less and Mn: 2.0% or less, with the remainder being substantially Fe. The magnetic shielding material has a relative magnetic permeability of 40,000 or more under a magnetic field of 0.05 A/m and a squareness ratio (Br/B0.8) of 0.85 or less, wherein the squareness ratio (Br/B0.8) is a ratio of a remanent magnetic flux density (Br) to a maximum magnetic flux density (B0.8) in a DC hysteresis curve produced under the maximum magnetic field of 0.8 A/m.
    Type: Application
    Filed: February 12, 2008
    Publication date: February 25, 2010
    Applicant: Hitachi Metals Ltd
    Inventors: Shin-ichiro Yokoyama, Yasuyuki Iida, Hakaru Sasaki, Yoji Ishikura, Hiromitsu Itabashi, Masahiro Mita, Yoshiyuki Fujihara
  • Patent number: 7626301
    Abstract: An electric rotating machine having permanent magnets having a rotor having a plurality of permanent magnets, a stator iron core disposed in opposite relation with the rotor, and a stator winding wound around the stator core, wherein the stator core is constituted by a yoke and a plurality of teeth portions disposed to the yoke. The teeth portions are projected towards the inner periphery of the rotor. The teeth portions are made of amorphous magnetic material.
    Type: Grant
    Filed: September 22, 2005
    Date of Patent: December 1, 2009
    Assignees: Japan Servo Co., Ltd., Hitachi Powdered Metals Co., Ltd., Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Metals, Ltd.
    Inventors: Yuji Enomoto, Haruo Koharagi, Motoya Ito, Katsuyuki Yamasaki, Ryoso Masaki, Shoji Ohiwa, Chio Ishihara, Masahiro Mita
  • Publication number: 20090085416
    Abstract: This invention provides a soft magnetic yoke-integrated bonded magnet in which a soft magnetic yoke has been integrally compression molded in such a state that the soft magnetic yoke is engaged in a joined face formed by bringing a binding material-containing magnetic powder into contact with a binding material-containing soft magnetic powder. The soft magnetic yoke part and the bonded magnetic part are constructed so that, when the soft magnetic yoke part and the bonded magnet part are compression molded separately from each other, the spring back level is identical upon the release of the compression force.
    Type: Application
    Filed: February 28, 2007
    Publication date: April 2, 2009
    Applicant: HITACHI METALS, LTD.
    Inventors: Masahiro Masuzawa, Masahiro Mita, Shigeho Tanigawa, Kyohei Aimuta
  • Patent number: 7511679
    Abstract: A magnetic sensor-type antenna comprising a magnetic core and a coil wound around the magnetic core for receiving electromagnetic waves, which is disposed in a housing such that the end portion of the magnetic core is bent away from the housing or a metal portion of the housing, and a timepiece, a keyless entry system and an RFID system each comprising such an antenna.
    Type: Grant
    Filed: November 29, 2004
    Date of Patent: March 31, 2009
    Assignee: Hitachi Metals Ltd.
    Inventors: Hirokazu Araki, Masahiro Mita, Chiharu Mitsumata
  • Patent number: 7463208
    Abstract: An antenna comprising a magnetic main-path member comprising a coil wound around a magnetic core, and a magnetic sub-path member magnetically connected to the magnetic core for constituting a substantially closed magnetic path with the magnetic main-path member, the antenna meeting the relation of (S/N)1>(S/N)0, wherein (S/N)1 is a ratio of a signal voltage S obtained from the coil to a noise voltage N in this antenna, and (S/N)0 is a ratio of a signal voltage S to a noise voltage N in an antenna having the same structure except for having no magnetic sub-path member.
    Type: Grant
    Filed: July 3, 2006
    Date of Patent: December 9, 2008
    Assignee: Hitachi Metals, Ltd.
    Inventors: Hirokazu Araki, Chiharu Mitsumata, Masahiro Mita
  • Publication number: 20080218007
    Abstract: A surface magnet type rotor and an inner magnet type rotor having good motor characteristics in which bonding strength is high between a magnet section and a soft magnetic yoke section, and structural reliability is high even in high speed use, and its producing method. The rotor comprises an anisotropic bond magnet section and a soft magnetic section wherein the anisotropic bond magnet section is preformed in magnetic field and then formed to be integrated with the soft magnetic section in nonmagnetic field. Subsequently, it is heat hardened to produce a surface magnet type rotor. Magnet units, each having a magnetic pole composed by bonding a pair of permanent magnets such that the directions of magnetization become symmetric with respect to the bonding surface, are linked such that magnetic poles of different polarities appear alternately on the magnetic action surface thus forming an anisotropic magnet body.
    Type: Application
    Filed: December 19, 2005
    Publication date: September 11, 2008
    Applicant: HITACHI METALS, LTD.
    Inventors: Masahiro Masuzawa, Masahiro Mita, Keiko Kikuti
  • Publication number: 20080148176
    Abstract: When a digital camera is set to retrieval mode, a map-style retrieval screen having a matrix structure is displayed on a display device. The digital camera searches for images photographed in the regions corresponding to each cell in the matrix structure, based on shooting location information appended to the images. The number of found images is displayed within each cell. When the user inputs a zoom in or zoom out command, the regions corresponding to each cell are made smaller or larger, according to the command. At the same time, a new retrieval is performed for images photographed in the regions corresponding to each of the modified cells. The number displayed within each cell is updated according to the number of images found in the new retrieval. When a single cell is selected, a list view of the images photographed in the region corresponding to the selected cell is displayed.
    Type: Application
    Filed: December 14, 2007
    Publication date: June 19, 2008
    Applicant: Casio Computer Co., Ltd.
    Inventor: Masahiro Mita
  • Patent number: 7336865
    Abstract: An optical switch for switching the connection of one or more movable optical fibers to one or more stationary optical fibers, comprising a movable soft magnetic block connected to an end portion of each movable optical fiber, a stationary soft magnetic block connected to each stationary optical fiber and fixed at a position opposing the movable block, an actuator for moving the movable block relative to the stationary block, and a means for positioning the movable block relative to the stationary block; the actuator comprising a yoke having a base portion and a pair of arms extending from both ends of the base portion such that they sandwich the movable block in its moving direction, a permanent magnet attached to the base portion of the yoke, and a coil mounted to at least one arm; and regardless of the position of the movable block, a magnetic flux generated by the permanent magnet being more in a first gap between one arm and the movable block than in a second gap between the other arm and the movable blo
    Type: Grant
    Filed: December 20, 2004
    Date of Patent: February 26, 2008
    Assignee: Hitachi Metals, Ltd.
    Inventor: Masahiro Mita
  • Publication number: 20070024516
    Abstract: An antenna comprising a magnetic main-path member comprising a coil wound around a magnetic core, and a magnetic sub-path member magnetically connected to the magnetic core for constituting a substantially closed magnetic path with the magnetic main-path member, the antenna meeting the relation of (S/N)1>(S/N)0, wherein (S/N)1 is a ratio of a signal voltage S obtained from the coil to a noise voltage N in this antenna, and (S/N)0 is a ratio of a signal voltage S to a noise voltage N in an antenna having the same structure except for having no magnetic sub-path member.
    Type: Application
    Filed: July 3, 2006
    Publication date: February 1, 2007
    Inventors: Hirokazu ARAKI, Chiharu Mitsumata, Masahiro Mita
  • Publication number: 20060255894
    Abstract: It is desired to design a coreless motor in which a gap size is set to be as small as possible, and a magnet having a large energy product is used in order to increase the gap magnetic flux density since the coreless motor has no iron core so that the magnetic flux density is small in the gap part. A rotor core of the motor has a permanent magnet rotor which is formed by a compression molding means, and which is formed of a compact formed by molding a powder material, the compact comprising a bond magnetic portion mainly composed of a binder and a magnetic powder, and a soft magnetic portion mainly composed of a binder and a soft magnetic powder, the bond magnetic portion having magnetic poles having at least one surface which is mechanically bonded to the soft magnetic portion, in order to solve the inherent problems.
    Type: Application
    Filed: May 9, 2006
    Publication date: November 16, 2006
    Inventors: Yuji Enomoto, Motoya Ito, Ryoso Masaki, Koichiro Ohara, Masahiro Mita, Matahiro Komuro, Masahiro Masuzawa
  • Publication number: 20060214866
    Abstract: A magnetic sensor-type antenna comprising a magnetic core and a coil wound around the magnetic core for receiving electromagnetic waves, which is disposed in a housing such that the end portion of the magnetic core is bent away from the housing or a metal portion of the housing, and a timepiece, a keyless entry system and an RFID system each comprising such an antenna.
    Type: Application
    Filed: November 29, 2004
    Publication date: September 28, 2006
    Inventors: Hirokazu Araki, Masahiro Mita, Chiharu Mitsumata
  • Publication number: 20060170301
    Abstract: A rotor comprising bonded magnet portions mainly composed of magnet powder and a binder, which are embedded in a soft magnetic portion mainly composed of soft magnetic powder and a binder, the rotor being produced by a compression-molding method, and the magnetic pole surfaces of the bonded magnet portions being embedded in the soft magnetic portion.
    Type: Application
    Filed: December 7, 2004
    Publication date: August 3, 2006
    Inventors: Masahiro Masuzawa, Shigeho Tanigawa, Masahiro Mita, Keiko Kikuchi
  • Publication number: 20060165347
    Abstract: An optical switch for switching the connection of one or more movable optical fibers to one or more stationary optical fibers, comprising a movable soft magnetic block connected to an end portion of each movable optical fiber, a stationary soft magnetic block connected to each stationary optical fiber and fixed at a position opposing the movable block, an actuator for moving the movable block relative to the stationary block, and a means for positioning the movable block relative to the stationary block; the actuator comprising a yoke having a base portion and a pair of arms extending from both ends of the base portion such that they sandwich the movable block in its moving direction, a permanent magnet attached to the base portion of the yoke, and a coil mounted to at least one arm; and regardless of the position of the movable block, a magnetic flux generated by the permanent magnet being more in a first gap between one arm and the movable block than in a second gap between the other arm and the movable blo
    Type: Application
    Filed: December 20, 2004
    Publication date: July 27, 2006
    Inventor: Masahiro Mita