Patents by Inventor Kiyomi Kawamura

Kiyomi Kawamura 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: 8183732
    Abstract: To improve tranquility and controllability of an iron core-equipped permanent magnet motor with an improved maximum energy product (BH)max by improving shape compatibility of a radial anisotropic magnet, there is provided a radial anisotropic magnet manufacturing method of fixing magnet powder in a net shape so as to maintain a magnetic anisotropic (C-axis) angle of a magnet with respect to a tangential line and for performing a deformation with a flow so as to have a predetermined circular arc shape or a predetermined annular shape. Particularly, by performing a deformation with a viscous flow or an extension flow, a deformability of the magnet is improved, and thus shape compatibility with respect to a thickness is. improved. A C-axis angle ? with respect to a tangential direction is controlled at an arbitrary position and an arbitrary angle so as to reduce cogging torque without separating a magnetic pole into segments.
    Type: Grant
    Filed: October 20, 2011
    Date of Patent: May 22, 2012
    Assignee: Panasonic Corporation
    Inventors: Fumitoshi Yamashita, Hiroshi Murakami, Kiyomi Kawamura
  • Publication number: 20120032537
    Abstract: To improve tranquility and controllability of an iron core-equipped permanent magnet motor with an improved maximum energy product (BH)max by improving shape compatibility of a radial anisotropic magnet, there is provided a radial anisotropic magnet manufacturing method of fixing magnet powder in a net shape so as to maintain a magnetic anisotropic (C-axis) angle of a magnet with respect to a tangential line and for performing a deformation with a flow so as to have a predetermined circular arc shape or a predetermined annular shape. Particularly, by performing a deformation with a viscous flow or an extension flow, a deformability of the magnet is improved, and thus shape compatibility with respect to a thickness is. improved. A C-axis angle ? with respect to a tangential direction is controlled at an arbitrary position and an arbitrary angle so as to reduce cogging torque without separating a magnetic pole into segments.
    Type: Application
    Filed: October 20, 2011
    Publication date: February 9, 2012
    Inventors: Fumitoshi YAMASHITA, Hiroshi Murakami, Kiyomi Kawamura
  • Patent number: 8100345
    Abstract: A needle is forced to open an injection hole by reducing a pressure of fuel in an injection control chamber to thereby inject fuel stored in a fuel storage, while the needle is forced to close the injection hole by increasing the pressure of fuel in the injection control chamber to thereby terminate injection of fuel from the injection hole. In a valve-closing stroke of the needle to close the injection hole, fuel pressure is supplied from a common accumulator to the fuel storage and the injection control chamber in such a manner that the pressure to supply fuel to the fuel storage is lower than that to supply fuel to the injection control chamber. In this way, a force acting on the needle toward the injection hole side can be increased in the valve-closing stroke, to thereby accelerate a valve-closing speed of the needle.
    Type: Grant
    Filed: July 21, 2005
    Date of Patent: January 24, 2012
    Assignees: Toyota Jidosha Kabushiki Kaisha, Denso Corporation
    Inventors: Yoshihiro Hotta, Yoshifumi Wakisaka, Kiyomi Kawamura
  • Patent number: 8072109
    Abstract: To improve tranquility and controllability of an iron core-equipped permanent magnet motor with an improved maximum energy product (BH)max by improving shape compatibility of a radial anisotropic magnet, there is provided a radial anisotropic magnet manufacturing method of fixing magnet powder in a net shape so as to maintain a magnetic anisotropic (C-axis) angle of a magnet with respect to a tangential line and for performing a deformation with a flow so as to have a predetermined circular arc shape or a predetermined annular shape. Particularly, by performing a deformation with a viscous flow or an extension flow, a deformability of the magnet is improved, and thus shape compatibility with respect to a thickness is improved. A C-axis angle ? with respect to a tangential direction is controlled at an arbitrary position and an arbitrary angle so as to reduce cogging torque without separating a magnetic pole into segments.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: December 6, 2011
    Assignee: Panasonic Corporation
    Inventors: Fumitoshi Yamashita, Hiroshi Murakami, Kiyomi Kawamura
  • Patent number: 8044547
    Abstract: In a radial-direction gap type magnet motor, when an energy density increases, a direction change M?/?p of a static magnetic field with respect to a mechanic angle between different poles increases in an exponential manner and thus to decrease a cogging torque of the motor is not compatible to increase a torque density. In order to solve the problem, assuming that ?t denotes a mechanic angle of a stator iron core teeth, ?p denotes a mechanical angle of a magnetic pole, and M? denotes an angle of a static magnetic field with respect to a circumferential tangential line of a radial magnetic pole center, a radial-direction type magnet motor in which ?t<?p, M? in a magnetic pole center region is 75 to 90°, and M?/?p?7 is satisfied in the magnetic pole end region of ?p×0.1°, and further, a static magnetic field generating source is configured as a magnetic anisotropic magnetic pole having an energy density (BH) max?150 kJ/m3 is provided.
    Type: Grant
    Filed: November 15, 2007
    Date of Patent: October 25, 2011
    Assignee: Panasonic Corporation
    Inventors: Fumitoshi Yamashita, Hiroshi Murakami, Yukihiro Okada, Kiyomi Kawamura
  • Patent number: 7902707
    Abstract: An anisotropic permanent magnet motor includes a stator and a rotor opposed to teeth of the stator with a gap therebetween, and the rotor includes an anisotropic permanent magnet disposed on a surface of a rotor yoke. The anisotropic permanent magnet has an orientation direction set in a direction normal to the outer-peripheral surface in a range of both ?r°/2 from a magnetic pole center and continuously inclined toward a magnetic pole end with respect to a direction normal to the outer-peripheral surface.
    Type: Grant
    Filed: November 12, 2008
    Date of Patent: March 8, 2011
    Assignee: Panasonic Corporation
    Inventors: Kiyomi Kawamura, Fumitoshi Yamashita, Hiroshi Murakami
  • Publication number: 20110012465
    Abstract: A rotor (21) is an interior permanent magnet rotor formed of a rotor core (24) in which a plurality of permanent magnets (25) are embedded at predetermined intervals. First protruding portions (26) and second protruding portions (27) are formed on an outer peripheral face of the rotor, the first protruding portions (26) each opposing the vicinity of a central portion of each of the permanent magnets and having a substantially arc-shaped cross section protruding outward and the second protruding portions (27) each opposing the vicinity of an end portion of each of the permanent magnets and protruding outward. One first protruding portion and two second protruding portions correspond to one permanent magnet. The formation of the first and second protruding portions as described above on the outer peripheral face of the rotor makes it possible to sufficiently reduce the torque ripple and the noise caused by the distortion of air-gap magnetic flux distribution.
    Type: Application
    Filed: March 6, 2009
    Publication date: January 20, 2011
    Applicant: PANASONIC CORPORATION
    Inventors: Kiyomi Kawamura, Takashi Ogawa, Hiroshi Murakami, Yuichi Yoshikawa, Yasuyuki Yokouchi
  • Publication number: 20100226802
    Abstract: A fan motor includes a pair of fans axially mounted to both sides of a rotary shaft of the motor. The motor includes an inner rotor placed inside a stator wound with windings and an outer rotor placed outside the stator. The motor thus has a dual-rotor structure where the inner rotor and the outer rotor are held such that both the rotors can rotate on the rotary shaft.
    Type: Application
    Filed: March 3, 2010
    Publication date: September 9, 2010
    Applicant: Panasonic Corporation
    Inventors: Kiyomi Kawamura, Hu Li, Yuichi Yoshikawa, Hiroshi Murakami, Yasushi Kato
  • Publication number: 20100218365
    Abstract: A process of manufacturing segments, an anisotropic direction of which is continuously changed in a plane vertically by a uniform magnetic field maintained in a constant direction and a process of arranging a plurality of segments on a circumference, extruding the segments in a ring shape by rheology based on the viscous deformation of the segments, from one thrust-direction end surface of the segments, and subsequently compressing the segments from both thrust-direction end surfaces of the segments are necessarily included. A ring magnet, anisotropy of which is controlled in a continuous direction, is provided, and a source for generating a static magnetic field has energy density (BH) max?160 to 180 kJ/m3.
    Type: Application
    Filed: May 20, 2009
    Publication date: September 2, 2010
    Applicant: Panasonic Corporation
    Inventors: Fumitoshi Yamashita, Kiyomi Kawamura, Yukihiro Okada, Hiroshi Murakami
  • Patent number: 7784492
    Abstract: In a direction control valve, a bottom face of an insertion hole of a first movable member is at a predetermined distance from a second movable member with respect to a first axial direction when communication between a first communication switching port and a communication object port is made and communication between a second communication switching port and the communication object port is broken. The bottom face contacts and pushes the second movable member in a second axial direction opposite to the first axial direction after the first movable member moves in the second axial direction by the predetermined distance while the first and second movable members move in the second axial direction to switch a port communicating with the communication object port from the first communication switching port to the second communication switching port.
    Type: Grant
    Filed: July 28, 2006
    Date of Patent: August 31, 2010
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Yoshihisa Yamamoto, Hirokuni Tomita, Yoshihiro Hotta, Yoshifumi Wakisaka, Kiyomi Kawamura
  • Patent number: 7759833
    Abstract: A motor generally has a contradictory relation between decrease of cogging torque and increase of torque density. To overcome this problem, continuous direction control is provided for anisotropy with modification of magnetic poles so that the average absolute value of differences between M? and 90×sin [?{2?/(360/p)}] is set to be 3° or less, where M? is a direction of anisotropy with respect to a radial tangent line of a magnetic pole plane, ? is a mechanical angle, and p is the number of pole pairs.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: July 20, 2010
    Assignee: Panasonic Corporation
    Inventors: Fumitoshi Yamashita, Hiroshi Murakami, Yukihiro Okada, Kiyomi Kawamura
  • Patent number: 7723877
    Abstract: A stator of a motor includes a stator core formed of a plurality of teeth and an annular yoke connecting the teeth to each other, and windings wound on the teeth. A rotor of the motor confronts the stator while supported rotatably, and includes a rotor magnet, a rotor core, and a position sensing magnet. The motor further includes a position sensor for sensing a rotational position of the rotor and a circuit board for supplying an electric current to the windings in response to the rotational position of the rotor. The rotor magnet, the rotor core, and the position sensing magnet are integrated into one unit, which is mounted on a shaft of the rotor.
    Type: Grant
    Filed: November 24, 2006
    Date of Patent: May 25, 2010
    Assignee: Panasonic Corporation
    Inventors: Hideharu Hiwaki, Hiroshi Murakami, Kiyomi Kawamura
  • Patent number: 7712684
    Abstract: A fuel injection valve which injects fuel from a nozzle hole includes a cavitation generation flow path in which a cavitation bubble is generated in fuel flowing inside the injection valve, and a bubble storage flow path which is connected to the cavitation generation flow path and the nozzle hole and which stores the cavitation bubble generated in the cavitation generation flow path. A fuel containing the cavitation bubble stored in the bubble storage flow path is injected from the nozzle hole so that atomization of an injected fuel spray is enhanced.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: May 11, 2010
    Assignee: Kabushiki Kaisha Toyota Chuo Kenkyusho
    Inventors: Ryo Masuda, Kiyomi Kawamura, Makoto Nagaoka
  • Patent number: 7683518
    Abstract: A motor includes a stator formed of a stator iron-core having salient pole iron-cores and windings, and a rotor having a rotor iron-core in which permanent magnets are buried. A magnetic pole centerline connecting a rotary center of the rotor to a magnetic pole center crosses an external shape of the rotor iron-core at end point X, and the magnetic-pole boundary line connecting the rotary center to a magnetic pole boundary point crosses the external shape of the rotor iron-core at end point Z. A straight line angled at a given angle ?a from the magnetic pole centerline has end point A. Then a sectional view of the rotor iron-core shows an arc drawn between the end points X and A, and the arc's center is the rotary center. The end points A and Z are connected by one or more than one straight lines in series.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: March 23, 2010
    Assignee: Panasonic Corporation
    Inventors: Yuichi Yoshikawa, Kiyomi Kawamura, Hiroshi Murakami, Hideharu Hiwaki, Yasushi Kamada, Hiroki Sato
  • Publication number: 20100066192
    Abstract: In a radial-direction gap type magnet motor, when an energy density increases, a direction change M?/?p of a static magnetic field with respect to a mechanic angle between different poles increases in an exponential manner and thus to decrease a cogging torque of the motor is not compatible to increase a torque density. In order to solve the problem, assuming that ?t denotes a mechanic angle of a stator iron core teeth, ?p denotes a mechanical angle of a magnetic pole, and M? denotes an angle of a static magnetic field with respect to a circumferential tangential line of a radial magnetic pole center, a radial-direction type magnet motor in which ?t<?p, M? in a magnetic pole center region is 75 to 90°, and M?/?p?7 is satisfied in the magnetic pole end region of ?p×0.1°, and further, a static magnetic field generating source is configured as a magnetic anisotropic magnetic pole having an energy density (BH) max?150 kJ/m3 is provided.
    Type: Application
    Filed: November 15, 2007
    Publication date: March 18, 2010
    Applicant: Panasonic Corporation
    Inventors: Fumitoshi Yamashita, Hiroshi Murakami, Yukihiro Okada, Kiyomi Kawamura
  • Publication number: 20090127960
    Abstract: An anisotropic permanent magnet motor includes a stator and a rotor opposed to teeth of the stator with a gap therebetween, and the rotor includes an anisotropic permanent magnet disposed on a surface of a rotor yoke. The anisotropic permanent magnet has an orientation direction set in a direction normal to the outer-peripheral surface in a range of both ?r°/2 from a magnetic pole center and continuously inclined toward a magnetic pole end with respect to a direction normal to the outer-peripheral surface.
    Type: Application
    Filed: November 12, 2008
    Publication date: May 21, 2009
    Inventors: Kiyomi Kawamura, Fumitoshi Yamashita, Hiroshi Murakami
  • Publication number: 20090128075
    Abstract: A stator of a motor includes a stator core formed of a plurality of teeth and an annular yoke connecting the teeth to each other, and windings wound on the teeth. A rotor of the motor confronts the stator while supported rotatably, and includes a rotor magnet, a rotor core, and a position sensing magnet. The motor further includes a position sensor for sensing a rotational position of the rotor and a circuit board for supplying an electric current to the windings in response to the rotational position of the rotor. The rotor magnet, the rotor core, and the position sensing magnet are integrated into one unit, which is mounted on a shaft of the rotor.
    Type: Application
    Filed: November 24, 2006
    Publication date: May 21, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Hideharu Hiwaki, Hiroshi Murakami, Kiyomi Kawamura
  • Publication number: 20090021097
    Abstract: A motor generally has a contradictory relation between decrease of cogging torque and increase of torque density. To overcome this problem, continuous direction control is provided for anisotropy with modification of magnetic poles so that the average absolute value of differences between M? and 90×sin [?{2?/(360/p)}] is set to be 3° or less, where M? is a direction of anisotropy with respect to a radial tangent line of a magnetic pole plane, ? is a mechanical angle, and p is the number of pole pairs.
    Type: Application
    Filed: November 21, 2007
    Publication date: January 22, 2009
    Inventors: Fumitoshi Yamashita, Hiroshi Murakami, Yukihiro Okada, Kiyomi Kawamura
  • Publication number: 20090007417
    Abstract: In order to improve tranquility and controllability of an iron core-equipped permanent magnet motor with an improvement of a maximum energy product (BH)max by improving a shape compatibility of a radial anisotropic magnet, there is provided a radial anisotropic magnet manufacturing method of fixing magnet powder in a net shape so as to maintain a magnetic anisotropic (C-axis) angle of a magnet with respect to a tangential line and for performing a deformation with a flow so as to have a predetermined circular arc shape or a predetermined annular shape. Particularly, by performing a deformation with a viscous flow or an extension flow, a deformability of the magnet is improved, and thus a shape compatibility with respect to a thickness is improved. AC-axis angle ? with respect to a tangential direction is controlled at an arbitrary position and an arbitrary angle so as to reduce cogging torque without separating a magnetic pole into segments.
    Type: Application
    Filed: March 16, 2007
    Publication date: January 8, 2009
    Inventors: Fumitoshi Yamashita, Hiroshi Murakami, Kiyomi Kawamura
  • Patent number: 7461634
    Abstract: A pressure boosting unit (110) is provided in each fuel injection valve of an engine (1). A pressure of fuel to be supplied to the fuel injection valve from a common rail (3) is boosted as required. An ECU (20) causes low pressure injection to be performed with the pressure boosting unit 110 being in a non-operated state, and high pressure injection to be performed with the pressure boosting unit (110) being in an operated state, and the pressure of the fuel being maintained at a boosted pressure. Based on the result, the ECU (20) corrects a fuel injection period of the fuel injection valve. Also, after the correction of the fuel injection period is completed, fuel injection is performed before the pressure of the fuel reaches the boosted pressure after the pressure boosting unit starts to be operated. Based on the result, operation starting timing of the pressure boosting unit is adjusted.
    Type: Grant
    Filed: February 24, 2005
    Date of Patent: December 9, 2008
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yoshimasa Watanabe, Ichiro Sakata, Yoshifumi Wakisaka, Yoshihiro Hotta, Kiyomi Kawamura, Kiyomi Nakakita