With Slots Or Holes To Guide Flux Patents (Class 310/156.57)
  • Patent number: 8860276
    Abstract: An electromagnetic steel sheet formed body to be used in a rotor core in which a forward rotational direction and a reverse rotational direction are assigned to a clockwise direction along a circumferential direction around an axial center when viewed from a visual line including the axial center, wherein a first hollow portion, a second hollow portion, and a rib partitioning the first hollow portion and the second hollow portion is formed at the electromagnetic steel sheet formed body such that permanent magnets constituting a plurality of poles are arranged substantially at regular intervals at predetermined pole pitch angles along the circumferential direction, and that the permanent magnet disposed at one pole is arranged in a segmented manner as the first permanent magnet and the second permanent magnet, when viewed from the visual line, and wherein the first hollow portion when viewed from the visual line is located closer to a side of the forward rotational direction than a centerline passing through a
    Type: Grant
    Filed: March 15, 2011
    Date of Patent: October 14, 2014
    Assignee: Honda Motor Co., Ltd.
    Inventor: Daijiro Takizawa
  • Patent number: 8853909
    Abstract: A first non-magnetic portion, a second non-magnetic portion, and a third non-magnetic portion are arranged around an axis, from an end toward the center of a permanent magnet burying hole. A fourth non-magnetic portion is further provided between the second non-magnetic portion and the third non-magnetic portion. Angles around the axis are determined as follows with reference to a position between permanent magnet burying holes. The position between the first non-magnetic portion and the second non-magnetic portion is expressed by a first angle. The position between the third non-magnetic portion and the fourth non-magnetic portion is expressed by a second angle, and the second angle is twice the first angle. The end of the third non-magnetic portion located closer to the pole center is expressed by a third angle.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: October 7, 2014
    Assignee: Daikin Industries, Ltd.
    Inventors: Keiji Aota, Akio Yamagiwa, Yoshiki Yasuda
  • Patent number: 8847454
    Abstract: A rotating electric machine includes a stator and a rotor. Each of magnetic poles of the rotor includes a magnet insertion hole, a permanent magnet that is inserted in the magnet insertion hole, and a nonmagnetic portion formed between the permanent magnet and an auxiliary salient pole. A portion of the rotor core located toward the stator relative to the nonmagnetic portion function as a bridge portion connecting a magnetic pole peace with the auxiliary salient pole. A side of the nonmagnetic portion located toward the stator includes a first side at the bridge portion, extending along a virtual circular arc passing through the permanent magnet insertion hole closest to the stator, and a side of the nonmagnetic portion located toward the auxiliary salient pole includes a second side extending away from the stator, with the first side and the second side connected through a curved line.
    Type: Grant
    Filed: August 24, 2010
    Date of Patent: September 30, 2014
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Yasuyuki Saito, Noriaki Hino, Tomoaki Kaimori, Shinji Sugimoto
  • Patent number: 8803394
    Abstract: In a rotor for a rotary electric machine, a plurality of magnetic poles are provided in a radially outer portion of the rotor iron core, at intervals in the circumferential direction. Each magnetic pole includes a pair of permanent magnets disposed apart from each other in the circumferential direction, and a magnetic flux-restraining hole that is formed and extended radially inwardly between radially inner end portions of the permanent magnets and that restrains flow of magnetic flux. The magnetic flux-restraining hole is extended so as to project beyond a position of the radially inner end portions to a radially outer side, between the pair of permanent magnets.
    Type: Grant
    Filed: February 2, 2012
    Date of Patent: August 12, 2014
    Assignees: Toyota Jidosha Kabushiki Kaisha, Aisin Seiki Kabushiki Kaisha, Aisin AW Co., Ltd.
    Inventors: Shinya Sano, Ken Takeda, Tomohiro Inagaki, Shinichi Otake, Tsuyoshi Miyaji, Akifumi Kurokawa
  • Patent number: 8803395
    Abstract: A rotor includes a plurality of permanent magnets arranged annularly around an axis and a rotor core. The rotor core includes 2N (where N is a natural number) magnetic pole faces and a plurality of magnetic barriers. The 2N magnetic pole faces produce, due to the plurality of permanent magnets, magnetic poles in a radial direction in such a manner that different polarities can be alternately produced around the axis. The magnetic barriers are provided at a side close to the magnetic pole faces relative to the permanent magnets. At least one of the magnetic barriers is provided in each region obtained by equally dividing the rotor core into (2N+1), ((N+1)×2) or ((N?1)×2) angles around the axis.
    Type: Grant
    Filed: July 9, 2010
    Date of Patent: August 12, 2014
    Assignee: Daikin Industries, Ltd.
    Inventors: Shintarou Araki, Akio Yamagiwa
  • Patent number: 8772994
    Abstract: Permanent-magnet (PM) rotors, rotor components, and machines using PM rotors, where the PM rotors have internally coupled PM bulks and/or are configured to have a non-uniform air gap between the rotor and a stator.
    Type: Grant
    Filed: August 28, 2009
    Date of Patent: July 8, 2014
    Assignee: Teco-Westinghouse Motor Company
    Inventors: Xueqing Feng, Lijun Liu
  • Patent number: 8766503
    Abstract: An accommodating recess (21A, 21B) has a magnet accommodating portion (19A, 19B) for accommodating a permanent magnet (17A, 17B) and a cavity (20A, 20B), which is located at the q-axis side of the magnet accommodating portion. The cavity opens through a rotor outer circumferential surface (162). A starting point (Pa1, Pb1) of an outer cavity forming surface (201A, 201B) is located on the rotor outer circumferential surface. The outer cavity forming surface intersects either a magnetic pole surface or an imaginary extended plane (23A, 23B) of a magnetic pole facing surface (191A, 191B). The rotor outer circumferential surface (162) includes portions of an imaginary annular line (E). A starting point (Pa1, Pb1) of the outer cavity forming surface (201A, 201B) is located between the d-axis and an intersection point (Qa, Qb) between the imaginary annular line and the imaginary extended plan of the magnetic pole facing surface.
    Type: Grant
    Filed: March 26, 2012
    Date of Patent: July 1, 2014
    Assignee: Kabushiki Kaisha Toyota Jidoshokki
    Inventors: Masanao Kagami, Ryo Umeyama, Yoshiyuki Nakane
  • Patent number: 8760025
    Abstract: A rotor core defines a plurality of cavities, and includes one magnet disposed within each cavity. Each magnet includes a cross section that defines an arcuate shape having an arc center. The magnets are arranged about a pole axis to define a first group of magnets disposed on a first side of the pole axis, and a second group of magnets disposed on a second side of the pole axis. The arc centers of each of the magnets of the first group of magnets and the second group of magnets are spaced from each other and are spaced from the pole axis. The plurality of magnets is arranged in a plurality of layers. The arc centers of each of the magnets in each of the layers are spaced from each other.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: June 24, 2014
    Assignee: GM Global Technologies Operations LLC
    Inventors: Khwaja M. Rahman, Sinisa Jurkovic
  • Patent number: 8754559
    Abstract: A rotor and a rotary electric machine containing the rotor are provided. The rotor includes a shaft, a rotor core coaxially connected to the shaft, a first axial magnetic steel and a second axial magnetic steel disposed at an end surface of the rotor core, a rotor bushing, and a first magnetic isolation groove. The first axial magnetic steel has a first magnetic pole facing the rotor core. The second axial magnetic steel has a second magnetic pole facing the rotor core. The rotor bushing is disposed at a side of the first and second axial magnetic steels opposite to the rotor core. The first magnetic isolation groove is formed in the rotor core along a radius direction of the rotor core. The first magnetic isolation groove is disposed between the first axial magnetic steel and the second axial magnetic steel to isolate the first pole and the second pole.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: June 17, 2014
    Assignee: Delta Electronics (Shanghai) Co., Ltd.
    Inventors: Hong-Liu Zhu, Jian-Ping Ying, Shi-Xiang Zhang
  • Patent number: 8729763
    Abstract: Disclosed are a rotor and an IPM motor capable of avoiding concentration of flux on a corner area of a magnet on the stator side, leading to reduction in demagnetizing field and accordingly reduction in a required coercive force, and reduction in the usage amount of dysprosium or the like and accordingly reduction in manufacturing cost. In a slot bored in a rotor core of a rotor making up a motor, at least one of a slot face on a center side of the rotor core and a slot face facing this slot face is formed a protrusion or a concave groove and the magnet to be inserted in the slot includes at least one of a concave groove and a protrusion to be engaged with the protrusion or the concave groove of the slot face at a position corresponding to the protrusion or the concave groove formed in the slot. Then, these concave groove and protrusion are engaged to form an engagement part.
    Type: Grant
    Filed: July 23, 2010
    Date of Patent: May 20, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Tomonari Kogure, Hiroko Kurihara
  • Patent number: 8714948
    Abstract: An object is to provide a permanent magnet motor that highly reduces torque fluctuation, thereby reducing noise and vibration. The permanent magnet motor may be formed as follows: a length D of a permanent magnet 8 in a longitudinal direction is the same as or longer than a width A between sides of the magnetic pole tooth 3 in the circumferential direction in an end portion of the magnetic pole tooth 3, and a distance C between tip portions of a pair of the first slits 13a and 13b within the same pole is smaller than the width A between the sides of the magnetic pole tooth 3 in the circumferential direction in the end portion of the magnetic pole tooth 3. The permanent magnet motor, thus formed, may be characterized in that cut surfaces 12 face the first slits 13a and 13b.
    Type: Grant
    Filed: February 26, 2007
    Date of Patent: May 6, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kazuhiko Baba, Hayato Yoshino, Koji Yabe, Masahiro Nigo, Koji Masumoto, Tomoaki Oikawa, Yoshio Takita
  • Patent number: 8680732
    Abstract: A rotary electric machine includes a rotor core, and a permanent magnet embedded in proximity to an outer circumferential portion of the rotor core, in which gaps for reducing irreversible demagnetization of the permanent magnet are provided on portions on an inner circumference side of the permanent magnet, the portions being of the rotor core in proximity to an inner circumferential surface of the permanent magnet.
    Type: Grant
    Filed: October 28, 2011
    Date of Patent: March 25, 2014
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventor: Takeshi Kamei
  • Patent number: 8674574
    Abstract: A rotor assembly with a cooling mechanism having first and second channels is provided. The rotor assembly includes a shaft having a hollow portion and a rotor core having at least one rotor stack positioned at least partially around the shaft. The rotor core has a first end and a second end. The rotor stack forms an interior cavity which is only partially filled with a permanent magnet so as to define a gap in the rotor stack. The first channel is configured to direct fluid flow in a generally radial direction from the hollow portion of the shaft. The second channel is at least partially defined by the gap in the interior cavity of the rotor stack and is configured to direct the fluid flow from the first channel to at least one of the first and second ends of the rotor core.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: March 18, 2014
    Assignee: GM Global Technology Operations LLC
    Inventors: Steven Lee Hayslett, Peter Bostwick, Edward L. Kaiser
  • Patent number: 8664823
    Abstract: A rotor for a permanent synchronous machine includes a rotor having a plurality of arcuately-shaped cavities formed within a rotor core structure. The plurality of arcuately-shaped cavities substantially concentrically layered with respect to an outer cylindrical wall of the rotor core structure. A plurality of permanent magnets is inserted within the plurality of arcuately-shaped cavities. Each cavity layer retains a permanent magnet of a first magnetic field strength disposed in end sections and a permanent magnet of a second magnetic field strength in a center section of each cavity layer. Each respective cavity includes an air barrier formed between the magnets having different magnetic field strengths. The air barrier generates a reluctance within an air barrier gap for directing a flow of flux generated by each third permanent magnet in a preceding layer in a direction toward each third permanent magnet in a succeeding layer.
    Type: Grant
    Filed: May 30, 2012
    Date of Patent: March 4, 2014
    Assignee: GM Global Technology Operations LLC
    Inventors: Rajeev Vyas, Thomas Wolfgang Nehl, Alexandru Rajala
  • Patent number: 8659200
    Abstract: The permanent magnet embedded rotating electrical machine includes a rotor and a plurality of flat permanent magnets. The rotor has on an outer periphery thereof a plurality of pairs of concave portions and a plurality of convex portions. Each of the convex portions is located between the pair of concave portions. The concave portions are formed at radially outward of respective adjacent magnetic pole ends of the permanent magnet. A bridge is provided in the rotor at an angular position about an axis of the rotor between opposed magnetic pole ends of two adjacent permanent magnets. Each concave portion at radially outward of the magnetic pole end of the permanent magnet is located close to the center of the same permanent magnet in relation to the bridge next to the permanent magnet in the circumferential direction of the rotor.
    Type: Grant
    Filed: September 14, 2010
    Date of Patent: February 25, 2014
    Assignee: Kabushiki Kaisha Toyota Jidoshokki
    Inventors: Taku Adaniya, Minoru Mera, Hiroshi Fukasaku
  • Patent number: 8643239
    Abstract: A motor including a rotor and a stator. The rotor includes a rotor core, magnet pole portions, and core pole portions. First magnetic pole portions, which are the magnet pole portions or the core pole portions, each include a first and second opposing parts arranged in an axial direction. Each first opposing part includes an auxiliary groove, and each second opposing part does not include an auxiliary groove. Where M(°) represents an open angle of the first magnetic pole portion, G(°) represents an open angle of the void, and L represents the number of teeth, an angle D1 from a center line in the circumferential direction of the first magnetic pole portion to the side surface in the auxiliary groove that is closer to the center line in the circumferential direction satisfies D1=M/2+G?a×360(°)/L (where a is a natural number).
    Type: Grant
    Filed: July 18, 2011
    Date of Patent: February 4, 2014
    Assignee: Asmo Co., Ltd.
    Inventors: Yoshiaki Takemoto, Shigemasa Kato, Seiya Yokoyama, Keisuke Koide
  • Patent number: 8618709
    Abstract: A rotary electric machine configured with a stator, rotor, and permanent magnets disposed in an inverted V-shape that becomes gradually narrower from a side of a center of rotation of the rotor. The rotor is provided with a plurality of support portions that extend radially about the center of rotation, and gap portions are respectively formed in correspondence with the plurality of support portions at positions spaced by a predetermined distance from an edge portion of the permanent magnets in a flowing direction of magnetic flux between the permanent magnets and the stator. The gap portions are formed to have such a length that causes magnetic saturation during generation of low torque in a low-current state and that causes no magnetic saturation during generation of maximum torque in a high-current state in which electricity at a high current is supplied to the stator coil.
    Type: Grant
    Filed: March 22, 2011
    Date of Patent: December 31, 2013
    Assignees: Aisin AW Co., Ltd., Toyota Jidosha Kabushiki Kaisha
    Inventors: Tomohiro Inagaki, Ken Takeda, Shinichi Otake, Tsuyoshi Miyaji, Yuta Watanabe, Ryosuke Utaka, Shinya Sano, Takeshi Tomonaga
  • Patent number: 8618708
    Abstract: In one embodiment, an apparatus includes a rotor shaft, at least one pole segment, at least one pole tip segment and at least one permanent magnet pair. The at least one pole segment is mechanically coupled to the rotor shaft. Each permanent magnet pair is disposed between the at least one pole segment and respective pole tip segment. The apparatus further includes at least one mechanical member that mechanically restrains the at least one pole tip segment to at least one of the rotor shaft or the at least one pole segment.
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: December 31, 2013
    Assignee: General Electric Company
    Inventors: Jeremy Daniel Van Dam, James Pellegrino Alexander, Murtuza Yusuf Lokhandwalla
  • Patent number: 8598763
    Abstract: A field element core has a perimeter exposed around a rotation axis and a plurality of field magnet insertion holes circularly disposed around the rotation axis P. A radius between the perimeter and the rotation axis P decreases in a monotonically non-increasing manner from a pole center toward an interpole and then increases in a monotonically non-decreasing manner in a region between the pole center and the interpole in a circumferential direction.
    Type: Grant
    Filed: April 22, 2009
    Date of Patent: December 3, 2013
    Assignee: Daikin Industries, Ltd.
    Inventors: Keiji Aota, Yoshihito Sanga, Akio Yamagiwa
  • Patent number: 8575807
    Abstract: An electric drive motor that is intended for a vehicle, in particular for a motor vehicle, includes a stator and a rotor with at least one pole pair, wherein each pole of a respective pole pair has a magnet arrangement having at least one buried magnetic layer. The drive motor is characterized in that each pole has a number of magnetic flux influencing groups, each of which has a number of air-filled recesses, which are not assigned to a magnet of a respective magnetic layer for purposes of flux conductance.
    Type: Grant
    Filed: April 25, 2012
    Date of Patent: November 5, 2013
    Assignee: Bayerische Motoren Werke Aktiengesellschaft
    Inventors: Joerg Merwerth, Jens Halbedel, Guenter Schlangen
  • Patent number: 8541919
    Abstract: A rotor structure for an interior permanent magnet (IPM) electromotive machine is provided. The rotor structure may include at least one rotor lamination, which in turn may include at least one slot arranged to receive at least one permanent magnet. The slot divides the rotor lamination into a pole region and a yoke region. At least one bridge is arranged to connect the pole region to the yoke region at an outer edge of the lamination. The outer edge of the lamination is profiled along a segment of the bridge to define a concave curved profile for the bridge. The concave curved profile for the bridge allows to selectively size a thickness of the bridge to affect at least some electromagnetic and/or mechanical characteristic of the machine.
    Type: Grant
    Filed: February 26, 2010
    Date of Patent: September 24, 2013
    Assignee: General Electric Company
    Inventors: Murtuza Lokhandwalla, Rammohan Rao Kalluri, Kiruba Sivasubramaniam Haran
  • Patent number: 8508094
    Abstract: A synchronous rotating electrical machine is disclosed, of the type including a stator (10) and a rotor (11). The rotor is of the flux concentration type and includes a plurality of alternate North and South poles formed from permanent magnets (PM). The magnets are housed in slots (E1) arranged in the magnetic body of the rotor. Each pole comprises a second slot (E3) roughly radial and arranged in the magnetic body of the pole, between two consecutive magnets delimiting the pole. In accordance with the invention, each pole includes a portion forming a bridge (BR) between the magnetic bodies of the rotor, on either side of the second slot, this part forming a bridge including a magnetic body height not greater than approximately one times the dimensional value of the width of the permanent magnets.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: August 13, 2013
    Assignee: Valeo Equipements Electriques Moteur
    Inventors: Jean-Claude Matt, Jérome Legranger
  • Patent number: 8487494
    Abstract: An interior permanent magnet machine is provided with a rotor that includes a plurality of slots and at least one barrier defined by the plurality of slots. A plurality of first and second magnets are disposed within the barrier. The rotor is configured such that at least one of the first magnets is located at a different radial distance from the center of the rotor relative to at least one of the second magnets. The rotor may be configured to produce an averaging effect similar to that achieved through traditional skewing of rotor magnets. The rotor includes a plurality of poles defined by respective pole axes in the rotor and may be configured to reflect radial asymmetry between poles (pole-to-pole) and/or radial asymmetry within a pole.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: July 16, 2013
    Assignee: GM Global Technology Operations LLC
    Inventors: Sinisa Jurkovic, Khwaja M. Rahman, Xinyu Zhou, Xu Han, Qiang Niu
  • Patent number: 8405271
    Abstract: An interior permanent magnet type brushless direct current (BLDC) motor includes a stator having a plurality of slots and a stator coil wound on the slots. The interior permanent magnet type brushless direct current (BLDC) motor also includes a rotor that rotates with respect to the stator and that has a rotor core and a plurality of permanent magnets positioned in the rotor core. The rotor has a notch that is cut off between adjacent permanent magnets.
    Type: Grant
    Filed: October 30, 2009
    Date of Patent: March 26, 2013
    Assignee: LG Electronics Inc.
    Inventors: Kyung-Hoon Lee, Jun-Ho Ahn
  • Patent number: 8390163
    Abstract: An electric rotating machine includes a stator, a rotor inserted in a bore of the stator such that an air gap is formed between the stator and the rotor, and a plurality of permanent magnets embedded in a peripheral portion of the rotor core of the rotor in a circumferential arrangement. Slits are formed in portions of the rotor core each extending between the adjacent magnetic poles. Compressive stress is induced in portions of the rotor core each extending between the slit and the permanent magnet when stress is induced in the portion of the stator core extending between the slit and the permanent magnet by centrifugal force produced when the rotor rotates and acting on the permanent magnet and a pole piece covering the permanent magnet.
    Type: Grant
    Filed: February 25, 2009
    Date of Patent: March 5, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Yasuyuki Saito, Tsuyoshi Goto, Noriaki Hino, Katsuhiro Hoshino
  • Patent number: 8373324
    Abstract: A field element core includes field magnet through holes and coupling part. The field magnet through holes are circularly disposed in a peripheral direction around a predetermined direction and are adjacent to each other in the peripheral direction to form a set. The field magnet through holes forming the same pair both extend along a given direction that is defined for each pair, when viewed from the predetermined direction. The coupling part 11 is provided between the field magnet through holes forming the same set and has ends as lateral surfaces, respectively. The entire lateral surfaces of the coupling part are curved to form a concave shape. Specifically, viewed from the predetermined direction, only at a given position between both ends of the lateral surface, a tangent of the lateral surface extends along an extending direction of the coupling part. The same holds true for the lateral surface.
    Type: Grant
    Filed: November 27, 2008
    Date of Patent: February 12, 2013
    Assignee: Daikin Industries, Ltd.
    Inventor: Kiyotaka Nishijima
  • Patent number: 8362668
    Abstract: A rotor for a rotating electrical machine suppresses demagnetization of permanent magnets without deteriorating motor characteristics, is low-cost, and is highly reliable. The rotor has a plurality of rotor cores that are stacked together, a plurality of permanent magnets axially divided by the rotor cores and circumferentially arranged on each of the rotor cores, to circumferentially form magnetic irregularities, and a rotor blank made of nonmagnetic material arranged between those of the rotor cores that are adjacent to each other.
    Type: Grant
    Filed: November 25, 2008
    Date of Patent: January 29, 2013
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Industrial Products Manufacturing Corporation
    Inventors: Norio Takahashi, Mikio Takabatake, Masanori Arata, Kazuto Sakai, Yutaka Hashiba, Wataru Ito, Tadashi Tokumasu, Masakatsu Matsubara
  • Patent number: 8350435
    Abstract: An interior permanent magnet machine has non-contiguous, non-magnetic radial slots between the magnets and the cylindrical periphery and the magnets have non-magnetic radial end slots.
    Type: Grant
    Filed: March 5, 2010
    Date of Patent: January 8, 2013
    Assignee: Emerson Electric Co.
    Inventors: Keith I. Hoemann, Todd A. Walls
  • Patent number: 8350434
    Abstract: For providing a permanent magnet type rotary electric machine that can reduce magnetic fluxes concentrated to one side in rotating direction on a magnetic pole circumferential face that causes torque ripple as well as ensure the mechanical strength, in the present invention, an outer circumference of respective magnetic poles is formed in a circular arc having a same curvature as well as the magnetic pole center axes of the respective magnetic poles are displaced with respect to the rotation center of a rotor so that an air gap between a stator and the respective magnetic pole outer circumferences at one side in the rotating direction is widened in comparison with the air gap at the other side.
    Type: Grant
    Filed: February 27, 2009
    Date of Patent: January 8, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Hori, Daisuke Kori, Akiyoshi Komura
  • Patent number: 8324779
    Abstract: A motor having a rotor and a stator is disclosed. The rotor is a consequent-pole rotor having a rotor core, a plurality of magnets, and a plurality of salient poles. The stator includes a plurality of teeth. A first auxiliary groove is formed in a surface of each salient pole that is opposed to the teeth. Each first auxiliary groove has first and second side surfaces facing each other in the circumferential direction. The first side surface is closer to a circumferential center of the salient pole than the second side surface. When the angle from the circumferential center line to the first side surface of each salient pole about the axis of the rotor is represented by KC1, the opening angle between the circumferential ends of the distal end of each tooth about the axis is represented by KA, and the opening angle between the circumferential ends of each salient pole about the axis is represented by KB, the following expression is satisfied: KC1=KA?KB/2.
    Type: Grant
    Filed: October 5, 2010
    Date of Patent: December 4, 2012
    Assignee: ASMO Co., Ltd.
    Inventors: Shigemasa Kato, Seiya Yokoyama, Yoji Yamada, Yoshiaki Takemoto, Keisuke Koide, Shinji Santo
  • Patent number: 8319386
    Abstract: A motor having a rotor and a stator is disclosed. A motor having a rotor and as stator is disclosed. The rotor is a consequent-pole rotor having a rotor core, a plurality of magnets, and a plurality of salient poles. The stator includes a plurality of teeth. The stator is arranged to be opposite to the rotor with a gap along the radial direction. The gap between the stator and the rotor is set to satisfy an expression 1<B/A, where A represents the shortest gap distance between the stator and the magnets, and B represents the shortest gap distance between the stator and the salient poles.
    Type: Grant
    Filed: October 5, 2010
    Date of Patent: November 27, 2012
    Assignee: ASMO Co., Ltd.
    Inventors: Yoji Yamada, Seiya Yokoyama, Yoshiaki Takemoto, Shigemasa Kato, Keisuke Koide, Shinji Santo
  • Patent number: 8304949
    Abstract: A magnet pole portion 31 is made up of an integral magnet 44 into which are integrated a main permanent magnet piece 41 which is magnetized in the direction of a rotational axis, a pair of auxiliary permanent magnet pieces 42, 42 which are disposed at circumferential sides on one side of the main permanent magnet piece 41 with respect to the direction of the rotational axis, which are each magnetized in the direction of the rotational axis and a direction which is at right angles to a radial direction and on which magnetic poles face each other which are the same as a magnetic pole on the one side of the main permanent magnet piece 41 with respect to the direction of the rotational axis, and a pair of auxiliary magnet pieces 43, 43 which are disposed at circumferential sides on the other side of the main permanent magnet piece 41 with respect to the direction of the rotational axis, which are each magnetized in the direction of the rotational axis and a direction which is at right angles to a radial direction
    Type: Grant
    Filed: November 20, 2009
    Date of Patent: November 6, 2012
    Assignee: Honda Motor Co., Ltd.
    Inventor: Keiichi Yamamoto
  • Patent number: 8294320
    Abstract: An interior permanent magnet (IPM) machine having a rotor and a stator is provided. The rotor includes a radially inner barrier devoid of magnets, and a radially outer barrier having at least one permanent magnet, each barrier having two pockets with one pocket disposed at an angle relative to the other. At least one of the pockets of the inner barrier has a shape of an irregular quadrilateral. At least one of the pockets of the outer barrier has a substantially trapezoidal shape with a first side generally parallel to a second side, wherein the first side has a portion slanted relative to the third side. In such an IPM machine, demagnetization of the outer barrier magnet is limited when operating temperatures and electrical current exceed operating conditions prescribed by design specifications.
    Type: Grant
    Filed: February 17, 2010
    Date of Patent: October 23, 2012
    Assignee: GM Global Technology Operations LLC
    Inventor: Rajeev Vyas
  • Patent number: 8242654
    Abstract: A motor is disclosed that includes a rotor having a consequent-pole structure. The rotor core of the rotor includes a magnetic flux dividing portion at each position that faces one of the magnets. Each magnetic flux dividing portion forcibly divides magnetic flux in the vicinity of the backside of the corresponding magnet to both sides in the circumferential direction.
    Type: Grant
    Filed: May 13, 2010
    Date of Patent: August 14, 2012
    Assignee: Asmo Co., Ltd.
    Inventors: Yoji Yamada, Seiya Yokoyama, Shigemasa Kato, Yoshiaki Takemoto, Yoko Tateishi
  • Patent number: 8232703
    Abstract: In an embedded magnet motor, radial magnets and first inclined magnets form north poles. The radial magnets and second inclined magnets form south poles. Core sheets each include preformed radial accommodating slots the number of which is expressed by P/2. Some of the preformed radial accommodating slots are short slots and the rest are long slots. The short slots are located at some parts of each radial accommodating slot along the axial direction. Radially inner ends of the short slots restrict the radial magnets from moving radially inward.
    Type: Grant
    Filed: November 15, 2011
    Date of Patent: July 31, 2012
    Assignee: ASMO Co., Ltd.
    Inventors: Takahiro Nakayama, Hirotaka Itoh, Yoshiyuki Takabe
  • Publication number: 20120187792
    Abstract: A motor includes: a rotor comprising: a rotary shaft; a magnetic body rotatable together with the rotary shaft; and first and second permanent magnets fixed on an outer circumference or an inner circumference of the magnetic body, and a stator comprising: an iron core arranged around the rotor; and a coil for exciting the iron core.
    Type: Application
    Filed: January 13, 2012
    Publication date: July 26, 2012
    Applicant: SHINANO KENSHI CO., LTD.
    Inventor: Nobuchika MARUYAMA
  • Patent number: 8227952
    Abstract: A synchronous machine comprises a stator and a rotor that faces the stator and rotates on a shaft thereof in a circumferential direction. The rotor has magnetic salient poles that generate reluctance torque and magnet-originating magnetic poles that generate magnet torque by using permanent magnets embedded in the rotor. The machine comprises means for shifting a magnetically substantial central position of magnetic flux emanating from the permanent magnets in the circumferential direction, by an electrical angle ?/2 plus a predetermined angle ??, from a reference position taken as a central position between paired magnetic salient poles composing each magnetic pole of the machine among the magnetic salient poles. Hence a maximum amplitude of a sum between a harmonic component of the magnet torque and the reluctance torque is changed from that obtained at the reference position without the shift.
    Type: Grant
    Filed: November 17, 2008
    Date of Patent: July 24, 2012
    Assignee: Denso Corporation
    Inventors: Akiya Shichijoh, Shin Kusase, Yuya Mizuma, Satoshi Ito
  • Patent number: 8198775
    Abstract: A magnetic gap is provided between a permanent magnet of a rotor and an auxiliary magnet pole portion which is arranged adjacent to the permanent magnet in a peripheral direction. A gradual change in a magnetic flux density distribution of a surface of the rotor is obtained and a cogging torque and a torque pulsation are restrained. By obtaining a reluctance torque according to the auxiliary magnetic pole, a permanent magnet electric rotating machine in which the cogging torque and the torque pulsation are restrained can be obtained and further an electromotive vehicle having the permanent magnet electric rotating machine can be provided.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: June 12, 2012
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keiji Oda
  • Patent number: 8198776
    Abstract: A current-energized synchronous motor (1) suitable in particular for vehicle drives. It includes a stator (2) and a rotor (3) carrying the energizer winding (7). The rotor (3) has at least two rotor poles (4) with one energizer winding (7) each. The rotor includes at least one selective magnetic flux barrier, in particular in the form of a radial slot (8) along the main axis (4A) of the rotor pole (4). This flux barrier is provided in each rotor pole (4) for increasing the reluctance moment of the current-energized synchronous motor (1).
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: June 12, 2012
    Assignee: BRUSA Elektronik AG
    Inventors: Arno Mathoy, Verena Mathoy, legal representative, Anna Mathoy, legal representative, Eva Mathoy, legal representative
  • Patent number: 8193666
    Abstract: An interior permanent magnet type brushless direct current (BLDC) motor includes a stator having a plurality of slots. The BLDC motor also includes a rotor positioned in the stator and that is rotatable with respect to the stator. The rotor has a rotor core, a plurality of permanent magnets inserted in the rotor core, a plurality of vent holes positioned between the center of the rotor core and the permanent magnets, and a plurality of coupling holes positioned between the permanent magnets and a periphery of the rotor core.
    Type: Grant
    Filed: October 28, 2009
    Date of Patent: June 5, 2012
    Assignee: LG Electronics Inc.
    Inventors: Seung-Suk Oh, Jin-Soo Park
  • Patent number: 8179011
    Abstract: A brushless motor including a stator having teeth and a rotor having magnetic pole portions is disclosed. The magnetic pole portions are arranged to have the same polarities as each other. The rotor includes gaps that function as magnetic resistance at circumferential ends of each of the magnetic pole portions so that an iron core portion is formed between the circumferentially adjacent magnetic pole portions. Magnetic flux of the magnetic pole portions passes through the iron core portion along the radial direction. The gaps include a first gap located on the leading end of the magnetic pole portion in the rotation direction of the rotor and a second gap located on the trailing end of the magnetic pole portion in the rotation direction of the rotor. The circumferential width of the first gap is set to be greater than the circumferential width of the second gap.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: May 15, 2012
    Assignee: ASMO Co., Ltd.
    Inventors: Yoshiaki Takemoto, Seiya Yokoyama, Yoji Yamada, Shigemasa Kato
  • Publication number: 20120112593
    Abstract: A rotor includes a plurality of permanent magnets arranged annularly around an axis and a rotor core. The rotor core includes 2N (where N is a natural number) magnetic pole faces and a plurality of magnetic barriers. The 2N magnetic pole faces produce, due to the plurality of permanent magnets, magnetic poles in a radial direction in such a manner that different polarities can be alternately produced around the axis. The magnetic barriers are provided at a side close to the magnetic pole faces relative to the permanent magnets. At least one of the magnetic barriers is provided in each region obtained by equally dividing the rotor core into (2N+1), ((N+1)×2) or ((N?1)×2) angles around the axis.
    Type: Application
    Filed: July 9, 2010
    Publication date: May 10, 2012
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Shintarou Araki, Akio Yamagiwa
  • Patent number: 8174158
    Abstract: In general, the various embodiments are directed to a permanent magnet machine (“PM machine”), and more specifically an internal permanent magnet machine (“IPM machine”) that includes rotor magnets configured asymmetrically with respect to the rotor periphery, thereby producing an averaging effect similar to that achieved through traditional skewing of the rotor magnets. In alternate embodiments, the span, placement and/or shape of the magnets may vary from one pole to the next.
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: May 8, 2012
    Assignee: GM Global Technology Operations LLC
    Inventors: Khwaja M. Rahman, Edward L. Kaiser, Peter J. Savagian
  • Patent number: 8102091
    Abstract: An electric machine includes a stator and a rotor core including a first rotor portion positioned adjacent the stator and having an outside diameter. The first rotor portion includes a plurality of elongated slots that define a plurality of poles. The electric machine also includes a plurality of magnets. Each of the plurality of magnets is positioned within one of the slots and arranged such that each of the plurality of poles has a magnetic arc length that is different than a magnetic arc length of any adjacent pole.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: January 24, 2012
    Assignee: Regal Beloit EPC Inc.
    Inventor: Dan M. Ionel
  • Patent number: 8080915
    Abstract: In an embedded magnet motor, radial magnets and first inclined magnets form north poles. The radial magnets and second inclined magnets form south poles. Core sheets each include preformed radial accommodating slots the number of which is expressed by P/2. Some of the preformed radial accommodating slots are short slots and the rest are long slots. The short slots are located at some parts of each radial accommodating slot along the axial direction. Radially inner ends of the short slots restrict the radial magnets from moving radially inward.
    Type: Grant
    Filed: December 7, 2010
    Date of Patent: December 20, 2011
    Assignee: Asmo Co., Ltd.
    Inventors: Takahiro Nakayama, Hirotaka Itoh, Yoshiyuki Takabe
  • Patent number: 8067872
    Abstract: The invention relates to a permanent magnet rotor for an electric motor, in which the permanent magnets inside the rotor extend parallel to the rotation axis of the rotor, and in the area of the radially outer longitudinal edges of the permanent magnets, grooves that are open to the outside are formed on the outer periphery of the rotor. These groves are each, in a peripheral direction, slanted or curved with regard to the longitudinal edge of the adjacent permanent magnets. The center line of each groove intersects the longitudinal edge of the adjacent permanent magnet at least once. The grooves on the outside of the rotor have, in the peripheral direction, a smaller width than in an area of the groove situated radially further inside, and the cross-sectional shape of the groove is constant over the length of the rotor. The invention also relates to a method for producing a rotor of the aforementioned type.
    Type: Grant
    Filed: November 7, 2005
    Date of Patent: November 29, 2011
    Assignee: Grundfos a/s
    Inventors: Henrik Ørskov Pedersen, Keld Folsach Rasmussen, Kjeld Hellegaard
  • Patent number: 8040010
    Abstract: The present invention comprises a stator, and a rotor which is disposed oppositely to the stator with a gap interposed. The stator comprises a stator core, and a distributed stator winding mounted to the stator core. The stator core comprises a ring-like yoke core, and a plurality of teeth cores which protrude from the yoke core in the radial direction. The rotor comprises a rotor core, and a plurality of permanent magnets embedded in the rotor core. A pair of non-magnetic portions is created inside the rotor core and on both sides of the circumferential width of a permanent magnet for one magnetic pole. In the rotor core located on the stator side of the pair of non-magnetic portions, a pair of magnetic paths is created as the result of the creation of the pair of non-magnetic portions. Furthermore, a groove or hole is created on the outer circumferential portion of the rotor core and between the adjacent magnetic poles.
    Type: Grant
    Filed: February 18, 2009
    Date of Patent: October 18, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Akinori Kamiya, Noriaki Hino, Fumio Tajima, Tsutomu Miyoshi, Hideki Nihei
  • Patent number: 8018111
    Abstract: A rotor core has permanent magnets. Magnetic flux of the permanent magnet of an even-numbered rotor magnetic pole part is guided in an axial direction by an axial magnetic path member. Magnetic flux of the permanent magnet of an odd-numbered rotor magnetic pole part is guided into a soft magnetic inner cylindrical part. The axial end faces of the inner cylindrical part and the axial magnetic path member protrude from the rotor core in the axial direction and face a stationary magnetic path member with a small gap therebetween. The amount of magnetic flux of the magnet, which the permanent magnet applies to a stator core is adjusted by an excitation current of an excitation coil wound on the stationary magnetic path member.
    Type: Grant
    Filed: June 2, 2009
    Date of Patent: September 13, 2011
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Hirofumi Kinjou, Sadahisa Onimaru
  • Patent number: 8013700
    Abstract: The present invention relates to a field element which reduces a harmonic component of a magnetic flux density. Permanent magnets (20) are in contact with first magnetic plates (1, 3) in a direction parallel to a rotation axis (P). The first magnetic plate (1) includes first and second magnetic members (10, 12) and first and second non-magnetic members (11, 13). The first magnetic member (10) includes a pole center and is in contact with one of the permanent magnets. The first magnetic member (10), the first non-magnetic member (11), the second magnetic member (12) and the second non-magnetic member (13) are disposed in the stated order in a circumferential direction with the pole center and the rotation axis being as a starting point and a center, respectively.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: September 6, 2011
    Assignee: Daikin Industries, Ltd.
    Inventors: Keiji Aota, Yoshinari Asano
  • Patent number: RE44037
    Abstract: A permanent magnet rotating electric machine comprises a stator having stator windings wound round a stator iron core and a permanent magnet rotor having a plurality of inserted permanent magnets in which the polarity is alternately arranged in the peripheral direction in the rotor iron core. The rotor iron core of the permanent magnets is composed of magnetic pole pieces, auxiliary magnetic poles, and a stator yoke, and furthermore has concavities formed on the air gap face of the magnetic pole pieces of the rotor iron core of the permanent magnets, gently tilting from the central part of the magnetic poles to the end thereof. In a permanent magnet rotating electric machine, effects of iron loss are reduced, and an electric car using highly efficient permanent magnet rotating electric machine are realized.
    Type: Grant
    Filed: December 23, 2009
    Date of Patent: March 5, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Masashi Kitamura, Noriaki Hino, Takashi Kobayashi, Shigeru Kakugawa, Takashi Yasuhara