Patents by Inventor Kohji Maki

Kohji Maki 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: 7138734
    Abstract: In order to reduce load supported by a support mechanism for supporting a movable part so as to prevent the movable part from moving in a horizontal direction when stress is generated thereon in the horizontal direction, there is provided a drive unit including a primary side having a magnetic body around which a coil is wound, and a secondary side having a plurality of permanent magnets, the primary side including magnetic poles and step portions provided on the magnetic poles. The width of each step portion is smaller than the width of each permanent magnet.
    Type: Grant
    Filed: May 10, 2005
    Date of Patent: November 21, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Houng Joong Kim, Kohji Maki, Yasuo Morooka, Isamu Numata, Hisao Tadokoro, Takeo Morimoto, Yasunori Sannohe, Hiroshi Ueno, Hideki Shimane
  • Patent number: 7093687
    Abstract: An angle-torque sensor has: a torque detection coil that detects a change in state quantity in a mechanism to detect a relative angle made between input axis and output axis of a torsion bar to be twisted by a torque; an angle detection coil that detects a change in state quantity in a mechanism to detect a rotation angle of a reduction axis which rotates with a rotation being transmitted from the input axis or output axis and being reduced by a reduction mechanism; a torque detection circuit that detects the relative angle from the output of the torque detection coil; and an angle detection circuit that detects the rotation angle from the output of the angle detection coil.
    Type: Grant
    Filed: April 7, 2005
    Date of Patent: August 22, 2006
    Assignee: Hitachi Cable, Ltd.
    Inventors: Ryoso Masaki, Satoru Kaneko, Kohji Maki, Ryoichi Menju
  • Patent number: 7057327
    Abstract: A vehicular alternator is provided which can effectively utilize the magnetic flux of a permanent magnet disposed between claw-type magnetic poles and can improve an output of the alternator. The vehicular alternator comprises a rotor and a stator constituted by coiling stator windings over a stator core, the rotor comprising a pair of claw-type magnetic poles arranged in an opposed relation, a permanent magnet disposed between adjacent two of a plurality of claws provided on the pair of claw-type magnetic poles, and field windings coiled radially inward of the plurality of claws. Each of the plurality of claws of the rotor is formed to have a shape coming into contact with the whole of a magnetic pole surface of the permanent magnet.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: June 6, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Kanazawa, Kenji Miyata, Kaoru Kawabata, Kohji Maki, Kazuo Tahara, Susumu Sasaki, Ryoichi Takahata
  • Publication number: 20060109006
    Abstract: A magnet for an NMR an analyzer includes a superconductor coil which is operated under a permanent current mode so as to generate a magnetic field in a space surrounded by the superconductor coil, and which enables a sample to be inserted into a measurement space in the magnetic space for analization. The superconductor coil includes a first access port for enabling access to the measurement space and a second access port for enabling insertion of the sample into the measurement space in a direction different from a direction of the first access port. An effective diameter of the first access port is larger than an effective diameter of the second access port when the effective diameters of the first and second access ports are defined as a diameter of a cylinder that is insertable into the first and second access ports.
    Type: Application
    Filed: January 12, 2006
    Publication date: May 25, 2006
    Inventors: Tsuyoshi Wakuda, Michiya Okada, Tomomi Kikuta, Kohji Maki, Hiroshi Morita, Shuichi Kido, Tomoo Chiba, Hideo Tsukamoto
  • Patent number: 7049913
    Abstract: The present invention provides a superconductivity magnet apparatus for generating a uniform magnetic field suitable for NMR applications. The superconductivity magnet apparatus has an access port for allowing an access to the center of the magnetic field from an external position separated away from the center in a direction other than the axial direction of a split-type superconductivity electromagnet employed in the magnet apparatus. In the superconductivity magnet apparatus, a gap exists between first and second superconductivity coil blocks facing each other to form the split-type superconductivity electromagnet. To put it in detail, the access port allows an access to a measurement space at the center of the magnet by way of the gap. A configuration element of the magnet such as a coil bobbin is cut out for providing the access port. An area including a deficiency portion caused by the cutout portion or the like is filled up with a material having a relative magnetic permeability in the range 1.
    Type: Grant
    Filed: February 26, 2004
    Date of Patent: May 23, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Tsuyoshi Wakuda, Kohji Maki, Mitsuyoshi Tsuchiya, Michiya Okada, Hideo Tsukamoto, Souji Kajiura, Shuichi Kido
  • Publication number: 20060091736
    Abstract: The conventional linear drive apparatus has the problem that in constructing a linear motor of a multiphase structure by connecting a plurality of armature units, the length of the armature becomes longer in proportion to the number of the phases, thus limiting the locations where the apparatus can be installed. The problem is solved by a linear drive apparatus comprising a plurality of armature units 3 formed by a magnetic material on which a conductor coil 4 is disposed, and an armature comprising an arrangement of the armature units 3. The armature units 3 comprise a plurality of opposing portions having opposing magnetic pole teeth. The magnetic pole teeth of adjacent opposing portions are arranged in an interdigitated manner. A secondary member 6 is disposed between magnetic pole teeth of the opposing portions. The armature units 3 comprise the coil 4 arranged on opposite sides thereof in an alternating manner.
    Type: Application
    Filed: December 12, 2005
    Publication date: May 4, 2006
    Inventors: Houng Kim, Kohji Maki, Misao Tadokoro, Hideki Shimane, Hitoshi Shibata, Keijiro Sakai
  • Patent number: 7004694
    Abstract: The conventional linear drive apparatus has the problem that in constructing a linear motor of a multiphase structure by connecting a plurality of armature units, the length of the armature becomes longer in proportion to the number of the phases, thus limiting the locations where the apparatus can be installed. The problem is solved by a linear drive apparatus comprising a plurality of armature units 3 formed by a magnetic material on which a conductor coil 4 is disposed, and an armature comprising an arrangement of the armature units 3. The armature units 3 comprise a plurality of opposing portions having opposing magnetic pole teeth. The magnetic pole teeth of adjacent opposing portions are arranged in an interdigitated manner. A secondary member 6 is disposed between magnetic pole teeth of the opposing portions. The armature units 3 comprise the coil 4 arranged on opposite sides thereof in an alternating manner.
    Type: Grant
    Filed: August 13, 2003
    Date of Patent: February 28, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Houng Joong Kim, Kohji Maki, Hisao Tadokoro, Hideki Shimane, Hitoshi Shibata, Keijiro Sakai
  • Publication number: 20050285597
    Abstract: At least one superconducting shim coil is wound around a cylinder member disposed approximately coaxially with a group of superconducting main coils, and the positions in the winding center locus in an axial direction change approximately in accordance with a function where a sine or cosine function with a cycle of (360/m) degrees (m; an integer of one or more) in a circumferential direction is mixed with a sine or cosine function with a cycle of (360/(m+2)) degrees.
    Type: Application
    Filed: June 27, 2005
    Publication date: December 29, 2005
    Inventors: Kohji Maki, Tsuyoshi Wakuda
  • Patent number: 6975048
    Abstract: A drive apparatus overcomes the problems of ensuring accurate mounting of a plurality of armature coils relative to a plurality of magnetic pole position detectors, limitations concerning the location for mounting, and the extension of primary-side length. The drive apparatus comprises a primary side including an arrangement of a plurality of armatures each having a core made of a magnetic material with coil windings. It also comprises a secondary side including a permanent magnet movably supported relative to the armatures via a gap. A magnetic pole position detector is disposed between adjacent armatures.
    Type: Grant
    Filed: July 28, 2003
    Date of Patent: December 13, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Houng Joong Kim, Kohji Maki, Hisao Tadokoro, Hideki Shimane, Hitoshi Shibata, Keijirou Sakai
  • Publication number: 20050264107
    Abstract: To reduce the magnetic flux leakage through the gap between magnetic pole teeth of an armature so as to reduce the magnetic attraction force generated between the armature and a needle, an armature unit is provided with two magnetic poles, on the top of which are magnetic pole teeth protruding toward the opposing magnetic pole, where the magnetic pole teeth of the magnetic pole are arranged at two heights, upper and lower, and the magnetic pole teeth of the opposing magnetic pole are arranged at two heights, upper and lower, so that the magnetic flux flows upward and downward alternately between the upper and lower magnetic pole teeth. The needle equipped with permanent magnets moves relatively in the gap between the upper and lower magnetic pole surfaces of the armature unit.
    Type: Application
    Filed: May 9, 2005
    Publication date: December 1, 2005
    Inventors: Kim Joong, Hiroshi Katayama, Kohji Maki
  • Publication number: 20050200209
    Abstract: In order to reduce load supported by a support mechanism for supporting a movable part so as to prevent the movable part from moving in a horizontal direction when stress is generated thereon in the horizontal direction, there is provided a drive unit including a primary side having a magnetic body around which a coil is wound, and a secondary side having a plurality of permanent magnets, the primary side including magnetic poles and step portions provided on the magnetic poles. The width of each step portion is smaller than the width of each permanent magnet.
    Type: Application
    Filed: May 10, 2005
    Publication date: September 15, 2005
    Inventors: Houng Kim, Kohji Maki, Yasuo Morooka, Isamu Numata, Hisao Tadokoro, Takeo Morimoto, Yasunori Sannohe, Hiroshi Ueno, Hideki Shimane
  • Patent number: 6943465
    Abstract: To reduce the magnetic flux leakage through the gap between magnetic pole teeth of an armature so as to reduce the magnetic attraction force generated between the armature and a needle, an armature unit is provided with two magnetic poles 1 and 2, on the top of which are magnetic pole teeth 11a, 12b, 21b, and 22a protruding toward the opposing magnetic pole, where the magnetic pole teeth of the magnetic pole 1 are arranged at two heights, upper and lower, and the magnetic pole teeth of the opposing magnetic pole 2 are arranged at two heights, upper and lower, so that the magnetic flux flows upward and downward alternately between the upper and lower magnetic pole teeth. The needle 6 equipped with permanent magnets moves relatively in the gap 8 between the upper and lower magnetic pole surfaces of the armature unit.
    Type: Grant
    Filed: March 29, 2004
    Date of Patent: September 13, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Houng Joong Kim, Hiroshi Katayama, Kohji Maki
  • Publication number: 20050173181
    Abstract: An angle-torque sensor has: a torque detection coil that detects a change in state quantity in a mechanism to detect a relative angle made between input axis and output axis of a torsion bar to be twisted by a torque; an angle detection coil that detects a change in state quantity in a mechanism to detect a rotation angle of a reduction axis which rotates with a rotation being transmitted from the input axis or output axis and being reduced by a reduction mechanism; a torque detection circuit that detects the relative angle from the output of the torque detection coil; and an angle detection circuit that detects the rotation angle from the output of the angle detection coil.
    Type: Application
    Filed: April 7, 2005
    Publication date: August 11, 2005
    Inventors: Ryoso Masaki, Satoru Kaneko, Kohji Maki, Ryoichi Menju
  • Patent number: 6926115
    Abstract: An angle-torque sensor has: a torque detection coil that detects a change in state quantity in a mechanism to detect a relative angle made between input axis and output axis of a torsion bar to be twisted by a torque; an angle detection coil that detects a change in state quantity in a mechanism to detect a rotation angle of a reduction axis which rotates with a rotation being transmitted from the input axis or output axis and being reduced by a reduction mechanism; a torque detection circuit that detects the relative angle from the output of the torque detection coil; and an angle detection circuit that detects the rotation angle from the output of the angle detection coil.
    Type: Grant
    Filed: July 31, 2003
    Date of Patent: August 9, 2005
    Assignee: Hitachi Cable, Ltd.
    Inventors: Ryoso Masaki, Satoru Kaneko, Kohji Maki, Ryoichi Menju
  • Publication number: 20050134414
    Abstract: The present invention provides a superconductivity magnet apparatus for generating a uniform magnetic field suitable for NMR applications. The superconductivity magnet apparatus has an access port for allowing an access to the center of the magnetic field from an external position separated away from the center in a direction other than the axial direction of a split-type superconductivity electromagnet employed in the magnet apparatus. In the superconductivity magnet apparatus, a gap exists between first and second superconductivity coil blocks facing each other to form the split-type superconductivity electromagnet. To put it in detail, the access port allows an access to a measurement space at the center of the magnet by way of the gap. A configuration element of the magnet such as a coil bobbin is cut out for providing the access port. An area including a deficiency portion caused by the cutout portion or the like is filled up with a material having a relative magnetic permeability in the range 1.
    Type: Application
    Filed: February 26, 2004
    Publication date: June 23, 2005
    Inventors: Tsuyoshi Wakuda, Kohji Maki, Mitsuyoshi Tsuchiya, Michiya Okada, Hideo Tsukamoto, Souji Kajiura, Shuichi Kido
  • Patent number: 6876108
    Abstract: Disclosed herewith a compact linear motor provided with a plurality of magnetic pole teeth and used to increase the thrust force by canceling a magnetic attractive force working between the primary member and the secondary member. The linear motor comprises a primary member and a secondary member. The primary member includes cores formed with a magnetic material and an electromagnetic coil wound on the cores while the secondary member supported so as to be capable of moving relatively with respect to the primary member with a gap therebetween. In the linear motor, the coil that is wound commonly on the cores is also disposed between adjacent magnetic pole teeth.
    Type: Grant
    Filed: August 20, 2003
    Date of Patent: April 5, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Kohji Maki, Houng Joong Kim, Yasuo Morooka, Keijirou Sakai, Hitoshi Shibata, Hideki Shimane, Hisao Tadokoro, Takashi Kobayashi
  • Publication number: 20040257082
    Abstract: To access a measurement space 3 located at the center of the magnet, an access port is provided in the direction of the magnet's axis, a clearance 12 is provided in the coil winding portion, and another access port passes through the clearance so that a sample can be positioned perpendicularly to the coil axis. According to this configuration, an access port passing through the coil winding portion can be smaller than the access port passing through the coil axis, a sample is inserted from the access port, a probe is inserted from the access port passing through the magnet axis, and thus the clearance can be minimized.
    Type: Application
    Filed: April 2, 2004
    Publication date: December 23, 2004
    Inventors: Tsuyoshi Wakuda, Michiya Okada, Tomomi Kikuta, Kohji Maki, Hiroshi Morita, Shuichi Kido, Tomoo Chiba, Hideo Tsukamoto
  • Patent number: 6825581
    Abstract: To reduce the magnetic flux leakage through the gap between magnetic pole teeth of an armature so as to reduce the magnetic attraction force generated between the armature and a needle, an armature unit is provided with two magnetic poles 1 and 2, on the top of which are magnetic pole teeth 11a, 21b, and 22a protruding toward the opposing magnetic pole, where the magnetic pole teeth of the magnetic pole 1 are arranged at two heights, upper and lower, and the magnetic pole teeth of the opposing magnetic pole 2 are arranged at two heights, upper and lower, so that the magnetic flux flows upward and downward alternately between the upper and lower magnetic pole teeth. The needle 6 equipped with permanent magnetic moves relatively in the gap 8 between the upper and lower magnetic pole surfaces of the armature unit.
    Type: Grant
    Filed: November 1, 2001
    Date of Patent: November 30, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Kim Houng Joong, Hiroshi Katayama, Kohji Maki
  • Publication number: 20040189104
    Abstract: In order to reduce load supported by a support mechanism for supporting a movable part so as to prevent the movable part from moving in a horizontal direction when stress is generated thereon in the horizontal direction, there is provided a drive unit including a primary side having a magnetic body around which a coil is wound, and a secondary side having a plurality of permanent magnets, the primary side including magnetic poles and step portions provided on the magnetic poles. The width of each step portion is smaller than the width of each permanent magnet.
    Type: Application
    Filed: April 12, 2004
    Publication date: September 30, 2004
    Inventors: Houng Joong Kim, Kohji Maki, Yasuo Morooka, Isamu Numata, Hisao Tadokoro, Takeo Morimoto, Yasunori Sannohe, Hiroshi Ueno, Hideki Shimane
  • Publication number: 20040178684
    Abstract: To reduce the magnetic flux leakage through the gap between magnetic pole teeth of an armature so as to reduce the magnetic attraction force generated between the armature and a needle, an armature unit is provided with two magnetic poles 1 and 2, on the top of which are magnetic pole teeth 11a, 12b, 21b, and 22a protruding toward the opposing magnetic pole, where the magnetic pole teeth of the magnetic pole 1 are arranged at two heights, upper and lower, and the magnetic pole teeth of the opposing magnetic pole 2 are arranged at two heights, upper and lower, so that the magnetic flux flows upward and downward alternately between the upper and lower magnetic pole teeth. The needle 6 equipped with permanent magnets moves relatively in the gap 8 between the upper and lower magnetic pole surfaces of the armature unit.
    Type: Application
    Filed: March 29, 2004
    Publication date: September 16, 2004
    Inventors: Kim Houng Joong, Hiroshi Katayama, Kohji Maki