Patents by Inventor Yuichi Yoshikawa

Yuichi Yoshikawa 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: 8362670
    Abstract: A plurality of stator teeth 2 are arranged at a constant interval in a circumferential direction on the inner circumferential face side or the outer circumferential face side of a ring-shaped stator core 1 that is made of a plurality of steel plates. The winding wire 5 is wound about the stator teeth. An insulator 4 that electrically insulates the stator core and the winding wire is provided therebetween. A gap 6 is formed between the winding wire and the insulator. Accordingly, a desired distance can be secured between the stator teeth and the winding wire regardless of the thickness of the insulator, and, thus, the influence of leakage magnetic fluxes that acts on the winding wire can be reduced. Accordingly, the influence of leakage magnetic fluxes formed near the stator teeth that acts on the winding wire can be reduced regardless of the thickness of the insulator.
    Type: Grant
    Filed: July 1, 2010
    Date of Patent: January 29, 2013
    Assignee: Panasonic Corporation
    Inventors: Takashi Ogawa, Yuichi Yoshikawa, Yasuo Yonei, Yasuji Echizen, Masahiko Kobayashi
  • Patent number: 8350433
    Abstract: It comprises stator including stator core having yoke and a plurality of teeth protruded from yoke, which is formed with slots between adjacent teeth, and rotor having rotor core and permanent magnet formed with a plurality of magnetic poles, which confronts tip ends of teeth via gaps, wherein rotor core is formed by rotor core materials circumferentially equally divided into the predetermined number of divisions, and the least common multiple being N for the number of slots and the number of magnetic poles and the least common multiple being M for the number of slots and the number of divisions, then N is equal to M.
    Type: Grant
    Filed: February 2, 2012
    Date of Patent: January 8, 2013
    Assignee: Panasonic Corporation
    Inventors: Hu Li, Yuichi Yoshikawa, Hiroshi Murakami
  • Patent number: 8350439
    Abstract: This motor includes a stator whereupon a plurality of magnetic poles are arranged at first prescribed intervals on the outer circumference section, and a rotor which is rotatively arranged on the outer circumference of the stator by having a prescribed space in between and has permanent magnets magnetized to different polarities at second prescribed intervals. The magnetic pole of the stator forms an extending section which extends from a magnetic pole base section in a direction parallel to the permanent magnet, and the extending length of the extending section in the direction parallel to the permanent magnet is same as that of the magnetic pole base section in the direction parallel to the permanent magnet or shorter.
    Type: Grant
    Filed: October 8, 2008
    Date of Patent: January 8, 2013
    Assignee: Panasonic Corporation
    Inventors: Yuichi Yoshikawa, Hiroshi Murakami, Atsuyoshi Koshiba, Koji Kadowaki, Haruki Kato, Yasuo Kunishige
  • Patent number: 8344570
    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: Grant
    Filed: March 6, 2009
    Date of Patent: January 1, 2013
    Assignee: Panasonic Corporation
    Inventors: Kiyomi Kawamura, Takashi Ogawa, Hiroshi Murakami, Yuichi Yoshikawa, Yasuyuki Yokouchi
  • Publication number: 20120286616
    Abstract: A clutch mechanism moving together with an actuator allows coupling or decoupling an inner rotor to or from a power shaft, thereby controlling a rotation angle. This structure allows a polarity of a magnetic pole of the inner rotor to be the same as that of an opposing magnetic pole of an outer rotor when the motor is driven at a low rpm, so that magnetic fluxes inter-linking with windings can be increased, which results in greater torque. When the motor is driven at a high rpm, the structure allows the polarity of the magnetic pole of the inner rotor to be different from that of the opposing magnetic pole of the outer rotor, so that an amount of leakage flux is increased, and the magnetic fluxes inter-linking with the winding are decreased. As a result, an induction voltage is lowered and a high rpm range is widened.
    Type: Application
    Filed: March 7, 2011
    Publication date: November 15, 2012
    Applicant: PANASONIC CORPORATION
    Inventors: Hu Li, Yuichi Yoshikawa, Hiroshi Murakami, Hideaki Matsuo, Yuichiro Tashiro
  • Patent number: 8207648
    Abstract: A dual-rotor motor in which inner slot angle ?i is larger than outer slot angle ?o. An inner notched portion is provided on both circumferential ends of an inner head. This inner notched portion provides a broader space between the inner head and an inner rotor toward both utmost ends of the inner head. An outer notched portion is provided on both circumferential ends of an outer head. This outer notched portion provides a broader space between the outer head and the outer rotor toward both utmost ends of the outer head.
    Type: Grant
    Filed: October 9, 2009
    Date of Patent: June 26, 2012
    Assignee: Panasonic Corporation
    Inventors: Hu Li, Yuichi Yoshikawa, Hiroshi Murakami
  • Publication number: 20120126651
    Abstract: It comprises stator including stator core having yoke and a plurality of teeth protruded from yoke, which is formed with slots between adjacent teeth, and rotor having rotor core and permanent magnet formed with a plurality of magnetic poles, which confronts tip ends of teeth via gaps, wherein rotor core is formed by rotor core materials circumferentially equally divided into the predetermined number of divisions, and the least common multiple being N for the number of slots and the number of magnetic poles and the least common multiple being M for the number of slots and the number of divisions, then N is equal to M.
    Type: Application
    Filed: February 2, 2012
    Publication date: May 24, 2012
    Applicant: Panasonic Corporation
    Inventors: Hu LI, Yuichi Yoshikawa, Hiroshi Murakami
  • Patent number: 8159097
    Abstract: A rotor 14 is rotatably disposed around a stator 13 that is provided with a plurality of magnetic poles 13a. The inner circumferential face of the rotor is provided with a magnet 15 on whose face opposing the stator main magnetization is performed, and on whose face opposing the substrate FG magnetization is performed. The outer circumferential ends of the magnetic poles of the stator are provided with extended portions 13b and 13c that vertically extend from the magnetic pole base 13d. A face of the substrate opposing the rotor is provided with a FG pattern 19 opposing the magnet 15. The FG pattern is disposed on an outer side in a radial direction of the outer circumferential face of the stator.
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: April 17, 2012
    Assignee: Panasonic Corporation
    Inventors: Yuichi Yoshikawa, Hiroaki Kawasaki, Kenji Sugiura, Hiroshi Ueda, Hiroki Asai
  • Patent number: 8159106
    Abstract: A stator 13 on whose outer circumference a plurality of magnetic poles 13a are arranged is mounted on a substrate 11, and a rotor 14 is rotatably disposed around the stator. The inner circumferential face of the rotor is provided with a magnet 15 magnetized to have alternately opposite polarities in a direction opposing the stator, and magnetized to have alternately opposite polarities in a direction opposing the substrate. The outer circumferential ends of the magnetic poles of the stator are provided with a first extended portion 13c that extends from a magnetic pole base 13d to the substrate side, and a second extended portion 13b that extends from the magnetic pole base to a side opposite the substrate side. A face of the substrate opposing the rotor is provided with a FG pattern 19 outside the outer circumferential face of the stator such that the FG pattern opposes the magnet.
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: April 17, 2012
    Assignee: Panasonic Corporation
    Inventors: Yuichi Yoshikawa, Hiroaki Kawasaki, Kenji Sugiura, Hiroshi Ueda, Hiroki Asai
  • Patent number: 8159102
    Abstract: A rotor 14 is rotatably disposed around a stator 13 that is provided with a plurality of magnetic poles 13a. The inner circumferential face of a rotor frame 14b of the rotor is provided with a magnet 15 magnetized to have alternately opposite polarities in a direction opposing the stator, and magnetized to have alternately opposite polarities in a direction opposing a substrate. The outer circumferential ends of the magnetic poles of the stator are provided with a first extended portion 13c that extends from a magnetic pole base 13d to a substrate 11 side, and a second extended portion 13b that extends from the magnetic pole base to a side opposite the substrate side. A face of the substrate opposing the rotor is provided with a FG pattern 19.
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: April 17, 2012
    Assignee: Panasonic Corporation
    Inventors: Yuichi Yoshikawa, Hiroaki Kawasaki, Kenji Sugiura, Hiroshi Ueda, Hiroki Asai
  • Patent number: 8134266
    Abstract: It comprises stator including stator core having yoke and a plurality of teeth protruded from yoke, which is formed with slots between adjacent teeth, and rotor having rotor core and permanent magnet formed with a plurality of magnetic poles, which confronts tip ends of teeth via gaps, wherein rotor core is formed by rotor core materials circumferentially equally divided into the predetermined number of divisions, and the least common multiple being N for the number of slots and the number of magnetic poles and the least common multiple being M for the number of slots and the number of divisions, then N is equal to M.
    Type: Grant
    Filed: April 3, 2008
    Date of Patent: March 13, 2012
    Assignee: Panasonic Corporation
    Inventors: Hu Li, Yuichi Yoshikawa, Hiroshi Murakami
  • Patent number: 8049382
    Abstract: A Hall element is placed under an outside rotor at an identical angular position to a centerline between two adjacent outer teeth. This structure allows narrowing a dead band of the Hall element when it senses a leakage magnetic flux.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: November 1, 2011
    Assignee: Panasonic Corporation
    Inventors: Yukinori Nakagawa, Yuichi Yoshikawa, Hu Li, Masahiko Morisaki, Yoshio Kobayashi
  • Publication number: 20110187222
    Abstract: A dual-rotor motor provided with a stator having a stator core including a yoke, a plurality of teeth and a coil wound around the stator core, an inner rotor and an outer rotor, wherein the stator core includes an annular yoke component forming the yoke, and a plurality of tooth components forming the teeth. The stator core is made by fitting the tooth components individually into the annular yoke component in a manner that one ends of the tooth components protrude from the inner peripheral side of the annular yoke component and the other ends protrude from the outer peripheral side of the annular yoke component.
    Type: Application
    Filed: October 21, 2009
    Publication date: August 4, 2011
    Applicant: Panasonic Corporation
    Inventors: Hu Li, Yuichi Yoshikawa, Hiroshi Murakami, Hideaki Matsuo, Yuichiro Tashiro, Koichi Mitamura, Hideto Inoue, Reiji Tajima, Eiji Hataya
  • Publication number: 20110175497
    Abstract: The motor comprises a stator, a rotor, and magnets. The stator has a plurality of magnetic poles circumferentially arranged at first spaced intervals. The rotor is rotatably arranged in a position opposing to the stator. The magnets are arranged at second spaced intervals circumferentially on a surface of the rotor. The stator is formed by laminating plate materials, and a plurality of laminated plate materials at least including outermost layers of a laminated body thereof are bent in a direction substantially parallel to the magnet in order to form extended portions. And, when a magnet opposed area of pole tip portion being closest to a magnet including the extended portion is S, and a sectional area of magnetic pole is A, then area ratio (S/A) fulfills the relation of 4.8>(S/A).
    Type: Application
    Filed: January 13, 2011
    Publication date: July 21, 2011
    Inventors: Hiroaki Kawasaki, Yuichi Yoshikawa, Atsuyoshi Koshiba, Yasuhiro Inoue, Koji Kadowaki, Yasuo Kunishige
  • Publication number: 20110050022
    Abstract: Supposing a straight line joining rotation center O of a rotor and a magnetic pole middle, that is, a middle of permanent magnets (25) to be a d-axis, and a straight line joining rotation center O and an intermediate point of mutually adjacent permanent magnets (25) to be a q-axis, mutually adjacent arcs A1 and A2 are composed such that radius R1 of arc A1 at the d-axis side is larger than radius R2 of arc A2 at the q-axis side, and that, at intersection point ? of mutual arcs A1 and A2, angle ? of tangent u of arc A2 at the q-axis side with respect to tangent t of arc A1 at the d-axis side is set by ?3 degrees???2 degrees.
    Type: Application
    Filed: March 21, 2008
    Publication date: March 3, 2011
    Applicant: Panasonic Corporation
    Inventors: Hu Li, Yuichi Yoshikawa, Hiroshi Murakami, Hiroki Sato
  • Publication number: 20110018382
    Abstract: A plurality of stator teeth 2 are arranged at a constant interval in a circumferential direction on the inner circumferential face side or the outer circumferential face side of a ring-shaped stator core 1 that is made of a plurality of steel plates. The winding wire 5 is wound about the stator teeth. An insulator 4 that electrically insulates the stator core and the winding wire is provided therebetween. A gap 6 is formed between the winding wire and the insulator. Accordingly, a desired distance can be secured between the stator teeth and the winding wire regardless of the thickness of the insulator, and, thus, the influence of leakage magnetic fluxes that acts on the winding wire can be reduced. Accordingly, the influence of leakage magnetic fluxes formed near the stator teeth that acts on the winding wire can be reduced regardless of the thickness of the insulator.
    Type: Application
    Filed: July 1, 2010
    Publication date: January 27, 2011
    Applicant: PANASONIC CORPORATION
    Inventors: Takashi OGAWA, Yuichi YOSHIKAWA, Yasuo YONEI, Yasuji ECHIZEN, Masahiko KOBAYASHI
  • 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: 20110006620
    Abstract: A stator 3 is provided with a plurality of magnetic poles 3a on the outer circumference thereof, and is configured from a plurality of layers of plate-shaped members. A rotor 4 is rotatably disposed around the stator. The inner circumferential face of the rotor is provided with a magnet 5. The outer circumferential ends of the magnetic poles of the stator are provided with an extended portion that is bent such that at least one plate-shaped member, including an outermost layer, of the plurality of plate-shaped members is substantially parallel to the magnet. When the inner diameter of a bent portion of a plate-shaped member that is the closest to the magnet of the at least one plate-shaped member constituting the extended portion is taken as R1i, and the thickness of the closest plate-shaped member is taken as T1, R1i<T1 is satisfied. Accordingly, it is possible to improve the driving efficiency of an outer rotor-type motor.
    Type: Application
    Filed: June 30, 2010
    Publication date: January 13, 2011
    Applicant: PANASONIC CORPORATION
    Inventors: Hiroaki KAWASAKI, Yuichi YOSHIKAWA, Atsuyoshi KOSHIBA, Koji KADOWAKI, Yasuo KUNISHIGE, Yasuhiro INOUE
  • Publication number: 20110001386
    Abstract: A stator 3 is provided with a plurality of magnetic poles 3a on the outer circumference thereof, and is configured from a plurality of layers of plate-shaped members. A rotor 4 is rotatably disposed around the stator. The inner circumferential face of the rotor is provided with a magnet 5. The outer circumferential ends of the magnetic poles of the stator are provided with an extended portion that is bent such that at least one plate-shaped member, including an outermost layer, of the plurality of plate-shaped members is substantially parallel to the magnet. When a thickness of a thinnest plate-shaped member of the at least one plate-shaped member constituting the extended portion is taken as T1, and a thickness of a thinnest plate-shaped member of a plate-shaped member not constituting the extended portion is taken as T2, T1 >T2 is satisfied. Accordingly, it is possible to improve the driving efficiency of an outer rotor-type motor.
    Type: Application
    Filed: June 30, 2010
    Publication date: January 6, 2011
    Applicant: PANASONIC CORPORATION
    Inventors: Hiroaki KAWASAKI, Yuichi YOSHIKAWA, Atsuyoshi KOSHIBA, Yasuhiro INOUE, Koji KADOWAKI, Yasuo KUNISHIGE
  • Publication number: 20100327691
    Abstract: A stator 13 on whose outer circumference a plurality of magnetic poles 13a are arranged is mounted on a substrate 11, and a rotor 14 is rotatably disposed around the stator. The inner circumferential face of the rotor is provided with a magnet 15 magnetized to have alternately opposite polarities in a direction opposing the stator, and magnetized to have alternately opposite polarities in a direction opposing the substrate. The outer circumferential ends of the magnetic poles of the stator are provided with a first extended portion 13c that extends from a magnetic pole base 13d to the substrate side, and a second extended portion 13b that extends from the magnetic pole base to a side opposite the substrate side. A face of the substrate opposing the rotor is provided with a FG pattern 19 outside the outer circumferential face of the stator such that the FG pattern opposes the magnet.
    Type: Application
    Filed: June 10, 2010
    Publication date: December 30, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Yuichi Yoshikawa, Hiroaki Kawasaki, Kenji Sugiura, Hiroshi Ueda, Hiroki Asai