Patents by Inventor Seiya Yokoyama

Seiya Yokoyama 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: 20180152064
    Abstract: This motor includes a two-layer rotor, a two-layer stator and a control unit. An A-phase rotor includes a pair of rotor cores and a field magnet. A B-phase rotor includes a pair of rotor cores and a field magnet. An A-phase stator includes a pair of stator cores and an A-phase winding. A B-phase stator includes a pair of stator cores and a B-phase winding. The control unit controls an A-phase input voltage applied to the A-phase winding, and a B-phase input voltage applied to the B-phase winding. The relative arrangement angle of the A-phase stator and the A-phase rotor relative to the B-phase stator and the B-phase rotor is set to an electrical angle of 90 degrees. The control unit applies a leading phase angle to the basic voltage waveforms of the A-phase input voltage and the B-phase input voltage, to set the energization width to at most 180 degrees.
    Type: Application
    Filed: August 18, 2016
    Publication date: May 31, 2018
    Applicant: ASMO CO., LTD.
    Inventors: Yoko TATEISHI, Yoshiaki TAKEMOTO, Masashi MATSUDA, Hironari SUZUKI, Seiya YOKOYAMA, Shigemasa KATO, Kazunori SHIMADA, Takahiro TSUCHIYA
  • Patent number: 9966807
    Abstract: A brushless motor includes a first rotor core, a second rotor core, and a field magnet member. The first rotor core includes primary projecting pieces arranged along a circumferential direction at equal intervals. The second rotor core has the same shape as the first rotor core, and includes secondary projecting pieces arranged along the circumferential direction at equal intervals. The secondary projecting pieces are positioned between the primary projecting pieces that are adjacent to one another in the circumferential direction. The field magnet member is arranged between the first rotor core and the second rotor core. The field magnet member is magnetized along an axial direction to generate primary magnetic poles in the primary projecting pieces, and generate secondary magnetic poles in the secondary projecting pieces. A rotor includes the first rotor core, the second rotor core, and the field magnet member.
    Type: Grant
    Filed: October 14, 2016
    Date of Patent: May 8, 2018
    Assignee: ASMO CO., LTD.
    Inventors: Seiya Yokoyama, Yoshiaki Takemoto
  • Publication number: 20180123434
    Abstract: A rotor with four axially stacked rotor cores, and a plurality of field magnets interposed between them. Each rotor core includes a rotor-side claw-shaped magnetic pole. Each rotor-side claw-shaped magnetic poles are respectively extending from and formed on each rotor core at equal angle intervals. Tip end surfaces of the first and third rotor-side claw-shaped magnetic pole abut against or are closely opposed to each other axially. Tip end surfaces of the second and fourth rotor-side claw-shaped magnetic poles abut against or are closely opposed to each other in the axial direction. The plurality of field magnets are magnetized in the axial direction such that the field magnets causes the first and third rotor-side claw-shaped magnetic poles to function as first magnetic poles, and cause the second and fourth rotor-side claw-shaped magnetic poles to function as second magnetic poles.
    Type: Application
    Filed: December 28, 2017
    Publication date: May 3, 2018
    Inventors: Yoshiaki TAKEMOTO, Yusuke MORIMOTO, Masashi MATSUDA, Seiya YOKOYAMA
  • Publication number: 20180076677
    Abstract: A rotor includes a first rotor core, a second rotor core, a permanent magnet and a resin layer. The first rotor core includes a first core base and first claw-shaped magnetic poles arranged at equal intervals on a peripheral portion of the first core base. The second rotor core includes a second core base and second claw-shaped magnetic poles arranged at equal intervals on a peripheral portion of the second core base. The first rotor core and the second rotor core are combined with each other so that the first and second core bases are opposed to each other and the first and second claw-shaped magnetic poles are alternately arranged in the circumferential direction of the rotor. The permanent magnet includes at least a main field magnet. The main field magnet is located between the first and second core bases in the axial direction, and is magnetized in the axial direction.
    Type: Application
    Filed: November 24, 2017
    Publication date: March 15, 2018
    Inventors: Yoji YAMADA, Chie MORITA, Seiya YOKOYAMA, Koji MIKAMI, Takahiro TSUCHIYA
  • Patent number: 9887608
    Abstract: A rotor with four axially stacked rotor cores, and a plurality of field magnets interposed between them. Each rotor core includes a rotor-side claw-shaped magnetic pole. Each rotor-side claw-shaped magnetic poles are respectively extending from and formed on each rotor core at equal angle intervals. Tip end surfaces of the first and third rotor-side claw-shaped magnetic pole abut against or are closely opposed to each other axially. Tip end surfaces of the second and fourth rotor-side claw-shaped magnetic poles abut against or are closely opposed to each other in the axial direction. The plurality of field magnets are magnetized in the axial direction such that the field magnets causes the first and third rotor-side claw-shaped magnetic poles to function as first magnetic poles, and cause the second and fourth rotor-side claw-shaped magnetic poles to function as second magnetic poles.
    Type: Grant
    Filed: January 21, 2014
    Date of Patent: February 6, 2018
    Assignee: ASMO CO., LTD.
    Inventors: Yoshiaki Takemoto, Yusuke Morimoto, Masashi Matsuda, Seiya Yokoyama
  • Publication number: 20180013327
    Abstract: A rotor of a motor includes first and second rotor cores, a field magnet, and a commutator magnet. The first and second rotor cores each include a core base and a plurality of claw poles. The claw poles of the first rotor core and the claw poles of the second rotor core are alternately arranged in a circumferential direction. The field magnet is located between the core bases. The field magnet is magnetized in an axial direction so that the claw poles of the first rotor core and the claw poles of the second rotor core function as different magnetic poles in the circumferential direction. The commutator magnet is located on an outer circumference of the field magnet around the claw poles. The commutator magnet is magnetized so that surfaces having the same polarity face each other between the claw poles and the commutator magnet.
    Type: Application
    Filed: September 22, 2017
    Publication date: January 11, 2018
    Applicant: ASMO CO., Ltd.
    Inventors: Yoji Yamada, Koji Mikami, Akihiro Utsumi, Akihisa Hattori, Chie Morita, Seiya Yokoyama
  • Publication number: 20180006513
    Abstract: A motor includes a stator, a rotor and a case. The rotor includes a first rotor core, a second rotor core, and a field magnet. Each of the first rotor core and the second rotor core includes a core base and a plurality of claw poles. The field magnet is located between the core bases. The case includes a cylindrical yoke housing and a lid. To balance magnetic flux from the first rotor core with magnetic flux from the second rotor core, the distance between the rotor and the stator is varied from the distance between the rotor and the yoke housing or the teeth of the stator are shaped to enable magnetic saturation.
    Type: Application
    Filed: September 19, 2017
    Publication date: January 4, 2018
    Inventors: Koji MIKAMI, Shigemasa KATO, Yoji YAMADA, Seiya YOKOYAMA
  • Patent number: 9859761
    Abstract: A rotor includes a first rotor core, a second rotor core, a permanent magnet and a resin layer. The first rotor core includes a first core base and first claw-shaped magnetic poles arranged at equal intervals on a peripheral portion of the first core base. The second rotor core includes a second core base and second claw-shaped magnetic poles arranged at equal intervals on a peripheral portion of the second core base. The first rotor core and the second rotor core are combined with each other so that the first and second core bases are opposed to each other and the first and second claw-shaped magnetic poles are alternately arranged in the circumferential direction of the rotor. The permanent magnet includes at least a main field magnet. The main field magnet is located between the first and second core bases in the axial direction, and is magnetized in the axial direction.
    Type: Grant
    Filed: January 17, 2014
    Date of Patent: January 2, 2018
    Assignee: ASMO CO., LTD.
    Inventors: Yoji Yamada, Chie Morita, Seiya Yokoyama, Koji Mikami, Takahiro Tsuchiya
  • Publication number: 20170366050
    Abstract: An axial gap motor rotor opposes a stator in an axial direction. The axial gap motor rotor includes a rotor core and a magnet. The magnet is arranged on the rotor core. The magnet is configured so that one axial end includes magnetic poles that alternately change in a circumferential direction. The rotor core includes a base, which is located at a center in a radial direction, and radial extensions, which are extended from the base outward in the radial direction and arranged in the circumferential direction. The magnet is configured to at least partially overlap the radial extensions in the axial direction. The radial extensions are located to include a boundary of adjacent ones of the magnetic poles in the circumferential direction.
    Type: Application
    Filed: June 19, 2017
    Publication date: December 21, 2017
    Inventors: Akihisa Hattori, Seiya Yokoyama, Yoji Yamada
  • Patent number: 9780610
    Abstract: A rotor includes first and second rotor cores, a field magnet, and an annular magnet. The first and second rotor cores each include a core base and core magnetic poles. The core magnetic poles are provided on an outer peripheral portion of the core base at equal intervals. The core bases are faced with each other. The core magnetic poles are alternately arranged in a peripheral direction. The annular magnet is a resin molding product including a magnetic pole magnet portion and an inter-pole magnet portion. The annular magnet has a non-contact portion not in contact with the first and second rotor cores. A gate mark portion in injection molding of the annular magnet is arranged in the non-contact portion.
    Type: Grant
    Filed: April 9, 2015
    Date of Patent: October 3, 2017
    Assignee: Asmo Co., Ltd.
    Inventors: Yoji Yamada, Chie Morita, Takahiro Tsuchiya, Seiya Yokoyama
  • Publication number: 20170279319
    Abstract: A motor includes a stator, a rotor, a case, and back-surface magnet portions. The rotor has a first rotor core, a second rotor core and a field magnet. Each of the first and second rotor cores has a core base and claw-shaped magnetic poles. The field magnet is sandwiched between the first rotor core and the second rotor core and causes the claw-shaped magnetic poles of the first rotor core and the second rotor core to function as different magnetic poles. The back-surface magnet portions include a second and a first back-surface magnet portions respectively provided on the back surfaces of the claw-shaped magnetic poles of the second rotor core and the first rotor core. Size of the second back-surface magnet portion differs from size of the first back-surface magnet portion are different from each other.
    Type: Application
    Filed: June 12, 2017
    Publication date: September 28, 2017
    Applicant: ASMO CO., LTD.
    Inventors: Yoji Yamada, Koji Mikami, Takahiro Tsuchiya, Hironari Suzuki, Seiya Yokoyama
  • Patent number: 9673669
    Abstract: A brushless motor includes a rotor. The rotor includes a first rotor core, a second rotor core and a field magnet. The first rotor core includes a plurality of first magnetic pole portions arranged in a circumferential direction. The second rotor core includes a plurality of second magnetic pole portions arranged in the circumferential direction. The field magnet is arranged between the first rotor core and the second rotor core in an axial direction. When the field magnet is magnetized in the axial direction, the first magnetic pole portions function as first magnetic poles and the second magnetic pole portions function as second magnetic poles.
    Type: Grant
    Filed: November 8, 2013
    Date of Patent: June 6, 2017
    Assignee: ASMO CO., LTD.
    Inventors: Yoji Yamada, Koji Mikami, Chie Morita, Takahiro Tsuchiya, Seiya Yokoyama, Takayoshi Suzuki
  • Patent number: 9667107
    Abstract: A motor including a stator and a rotor. The stator includes teeth and windings. Each tooth has a distal portion defined by a radially inward side of the stator. The rotor, which is arranged inward in the radial direction from the stator, includes a rotor core, magnets, and salient poles. Each salient pole is separated by a void from the magnet that is adjacent in the circumferential direction. The distal portion of each tooth is longer than a radially outward side of each magnet.
    Type: Grant
    Filed: May 27, 2014
    Date of Patent: May 30, 2017
    Assignee: Asmo Co., Ltd.
    Inventors: Yoji Yamada, Seiya Yokoyama, Keisuke Koide, Yoshiaki Takemoto, Shigemasa Kato
  • Patent number: 9653952
    Abstract: A motor includes a rotor and a stator. The rotor includes a plurality of magnets, which function as first magnetic poles, and salient poles, which function as second magnetic poles. A ratio X1:X2 of a quantity X1 of magnetic pole portions of the rotor, which is the sum of the quantity of the magnets and the quantity of the salient poles, and the quantity X2 of slots is 2n:3n (n being a natural number). The sum of a magnetic pole occupying angle ?1 of the magnet and a magnetic pole occupying angle ?2 of the salient pole is 360°. The magnetic pole occupying angle ?1 is set in a range of 180°<?1?230°.
    Type: Grant
    Filed: May 27, 2014
    Date of Patent: May 16, 2017
    Assignee: Amso Co., LTD.
    Inventors: Yoji Yamada, Seiya Yokoyama, Shigemasa Kato, Yoshiaki Takemoto, Yoko Tateishi
  • Patent number: 9584060
    Abstract: A motor includes a two-layer rotor and a two-layer stator. The two layer rotor includes an A-phase rotor and a B-phase rotor that are stacked together. When ?1 represents, in electric angle, an angle of the B-phase stator relative to the A-phase stator in a clockwise circumferential direction, and ?2 represents, in electric angle, an angle of the B-phase rotor relative to the A-phase rotor in a counterclockwise circumferential direction, ?1+|?2|=90° is satisfied.
    Type: Grant
    Filed: October 13, 2015
    Date of Patent: February 28, 2017
    Assignee: ASMO CO., LTD.
    Inventors: Yoshiaki Takemoto, Yoko Tateishi, Seiya Yokoyama, Yusuke Morimoto
  • Patent number: 9577496
    Abstract: A rotor includes a first rotor core, a second rotor core, a field magnet, and a detected portion. The first rotor core includes a first core base and a plurality of first claw-shaped magnetic pole portions. The second rotor core includes a second core base and a plurality of second claw-shaped magnetic pole portions. The first and second core bases face to each other, and the first and second claw-shaped magnetic pole portions are alternately arranged in the circumferential direction. The field magnet is located between the first and second core bases in the axial direction. The field magnet has the first claw-shaped magnetic pole portion function as a first magnetic pole and has the second claw-shaped magnetic pole portion function as a second magnetic pole. A detected portion, which generates a magnetic flux, is arranged at an outer axial end surface of the first rotor core.
    Type: Grant
    Filed: November 8, 2013
    Date of Patent: February 21, 2017
    Assignee: ASMO CO., LTD.
    Inventors: Shigemasa Kato, Yoji Yamada, Koji Mikami, Seiya Yokoyama
  • Publication number: 20170033623
    Abstract: A brushless motor includes a first rotor core, a second rotor core, and a field magnet member. The first rotor core includes primary projecting pieces arranged along a circumferential direction at equal intervals. The second rotor core has the same shape as the first rotor core, and includes secondary projecting pieces arranged along the circumferential direction at equal intervals. The secondary projecting pieces are positioned between the primary projecting pieces that are adjacent to one another in the circumferential direction. The field magnet member is arranged between the first rotor core and the second rotor core. The field magnet member is magnetized along an axial direction to generate primary magnetic poles in the primary projecting pieces, and generate secondary magnetic poles in the secondary projecting pieces. A rotor includes the first rotor core, the second rotor core, and the field magnet member.
    Type: Application
    Filed: October 14, 2016
    Publication date: February 2, 2017
    Inventors: Seiya YOKOYAMA, Yoshiaki TAKEMOTO
  • Publication number: 20160197527
    Abstract: A rotor of a motor includes first and second rotor cores, a field magnet, and a commutator magnet. The first and second rotor cores each include a core base and a plurality of claw poles. The claw poles of the first rotor core and the claw poles of the second rotor core are alternately arranged in a circumferential direction. The field magnet is located between the core bases. The field magnet is magnetized in an axial direction so that the claw poles of the first rotor core and the claw poles of the second rotor core function as different magnetic poles in the circumferential direction. The commutator magnet is located on an outer circumference of the field magnet around the claw poles. The commutator magnet is magnetized so that surfaces having the same polarity face each other between the claw poles and the commutator magnet.
    Type: Application
    Filed: December 18, 2015
    Publication date: July 7, 2016
    Applicant: ASMO CO., LTD.
    Inventors: Yoji Yamada, Koji Mikami, Akihiro Utsumi, Akihisa Hattori, Chie Morita, Seiya Yokoyama
  • Publication number: 20160111930
    Abstract: A motor includes a two-layer rotor and a two-layer stator. The two layer rotor includes an A-phase rotor and a B-phase rotor that are stacked together. When ?1 represents, in electric angle, an angle of the B-phase stator relative to the A-phase stator in a clockwise circumferential direction, and ?2 represents, in electric angle, an angle of the B-phase rotor relative to the A-phase rotor in a counterclockwise circumferential direction, ?1+|?2|=90° is satisfied.
    Type: Application
    Filed: October 13, 2015
    Publication date: April 21, 2016
    Applicant: ASMO CO., LTD.
    Inventors: Yoshiaki Takemoto, Yoko Tateishi, Seiya Yokoyama, Yusuke Morimoto
  • Patent number: 9273691
    Abstract: A rotor includes a first rotor core, a second rotor core, a field magnet, and an auxiliary magnet. The first rotor core includes a first core base and a plurality of first hook-shaped poles. The second rotor core includes a second core base and a plurality of second hook-shaped poles. The first and second hook-shaped poles are alternately arranged in a circumferential direction of the rotor. The field magnet is arranged between the first and second core bases in an axial direction. The field magnet cause the first hook-shaped poles to function as first poles and the second hook-shaped poles to function as second poles. The auxiliary magnet includes at least two interpolar magnet portions, which are integrally formed. Each interpolar magnet portion is arranged in a void between the first hook-shaped pole and the second hook-shaped pole and magnetized in the circumferential direction.
    Type: Grant
    Filed: October 29, 2012
    Date of Patent: March 1, 2016
    Assignee: ASMO, Co., Ltd.
    Inventors: Yoji Yamada, Chie Morita, Yoko Tateishi, Yuuki Fujii, Seiya Yokoyama