With Plural Sets Of Rotating Magnets Patents (Class 310/156.36)
  • Patent number: 7170212
    Abstract: A permanent magnet electrical machine comprises a first substantially planar member (9, 10) and a second substantially planar member (3) arranged substantially parallel to the first substantially planar member. The first and second members are rotatable relative to each other about a common axis substantially perpendicular to the planes of the first and second members. The first member (9, 10) is provided with an annular array of permanent magnets (7, 8) coaxial with the common axis and configured to provide a substantially axial magnetic field passing through the second member. The second member (3) is provided with a first annular array of flat coils (1) coaxial with the common axis and arranged substantially side-by-side in a first layer and with a second annular array of flat coils (2) coaxial with the common axis and arranged substantially side-by-side in a second layer. The coils (2) of the second array are offset in a circumferential direction relative to the coils (1) of the first array.
    Type: Grant
    Filed: December 2, 2002
    Date of Patent: January 30, 2007
    Assignee: Iska Wind Turbines Ltd
    Inventors: John Charles Balson, David Irving, Robert James Cann, Michael Andrew Wastling
  • Patent number: 7164216
    Abstract: A motor includes a stator section with a two-phase structure having first and second stator assemblies disposed in an axial direction, and a plurality of pole teeth arranged at an electrical angle of 90 degrees along inner circumferences of the first and second stator assemblies, and a rotor section including a rotation shaft, and first and second permanent magnets that are disposed opposite to and spaced a predetermined gap from the pole teeth and affixed to the rotation shaft with a gap provided between the first and second permanent magnets in the axial direction. Each of the first and second permanent magnets has an effective section at an outer circumference thereof that has multiple poles alternately magnetized with N poles and S poles, and has a protruded section that has a diameter smaller than an outer diameter of the effective section and protrudes in the axial direction.
    Type: Grant
    Filed: July 16, 2004
    Date of Patent: January 16, 2007
    Assignee: Nidec Sankyo Corporation
    Inventor: Takeshi Shimoyama
  • Patent number: 7126309
    Abstract: The electric machine of the present invention comprises a first coil group containing a plurality of coils and a magnet group. The first coil group is classified into M phase sub coil groups, with the coils of the sub coil groups aligned one at a time in sequence at a specified sub coil group interval Dc from the first phase sub coil group to the M-th phase sub coil group. A sub coil group interval Dc is set to a value of K/M times a magnetic pole pitch Pm (K is a positive integer excluding an integral multiple of M) where the distance corresponding to an electrical angle of ? is defined as the magnetic pole pitch Pm. The adjacent sub coil groups are driven at a (K/M)? phase difference. Each coil have substantially no magnetic material core.
    Type: Grant
    Filed: May 17, 2005
    Date of Patent: October 24, 2006
    Assignee: Seiko Epson Corporation
    Inventors: Kesatoshi Takeuchi, Takahiro Sagawa
  • Patent number: 7091636
    Abstract: A position-control stage system is disclosed, which is enhanced in prolusion to turn a turntable relatively to a bed through a bearing and also improved in operating performances including high-speed traveling and high response, even with made as small as allowed in diametral dimension. To this end, a motor includes a primary side having armature windings lying on a circular flat surface of a first retainer member secured to the bed, and a secondary side having a field magnet secured on the turntable. The bearing has an outer race held in place with combination of the bed and the first retainer member, and an inner race held in place with combination of the turntable and a second retainer member.
    Type: Grant
    Filed: April 28, 2005
    Date of Patent: August 15, 2006
    Assignee: Nippon Thompson Co., Ltd.
    Inventor: Masaki Ohno
  • Patent number: 7030529
    Abstract: A permanent magnet-excited electric motor with a rotating rotor having permanent magnets disposed with alternating polarities in a ring around its circumference, which magnets cooperate with coils of a stator encompassing the rotor. The permanent magnets, as individual magnets next to one another that are distributed uniformly over the circumference of the rotor, rest on an annular support and are clamped in place at their axial ends by a respective annular frame made of magnetically inactive material.
    Type: Grant
    Filed: January 29, 2003
    Date of Patent: April 18, 2006
    Assignee: Robert Bosch GmbH
    Inventors: Hans-Peter Dommsch, Guenter Kastinger
  • Patent number: 6982530
    Abstract: Provided is a drive system of a motor structured from a combined arrangement of a plurality of motors capable of reducing losses resulting from mechanical loss during the process of the driving force behind the motor being transmitted. This system has a plurality of motors mutually arranged adjacently, and a drive control unit of this motor, wherein the drive control unit drives the magnetic rotor by sending an excitation signal to at least one motor, and the magnetic rotors of the other motors are synchronously driven by the magnetic coupling with the magnetic field generated from the excitation driven magnetic rotor.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: January 3, 2006
    Assignee: Seiko Epson Corporation
    Inventor: Kesatoshi Takeuchi
  • Patent number: 6954014
    Abstract: The invention relates to a motor with a frequency generator attached thereto, equipped with the frequency generator (FG) for detecting a rotational speed of the motor.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: October 11, 2005
    Assignee: Japan Servo Co., Ltd.
    Inventors: Shoji Ohiwa, Yuji Enomoto, Tomoyoshi Maruyama, Yuji Takagai, Sachio Hatori, Kazuto Nagai
  • Patent number: 6897588
    Abstract: A brushless motor 1 comprises a rotor 3 having a magnet 2 and a stator 4 having a stator core 8. The stator core 8 has teeth 11 provided at the front ends thereof with auxiliary grooves to realize a pseudo-multi-slot arrangement. The magnet 2 has an axial length of LM while the stator core 8 has an axial length of LS, LS being greater than LM (LS>LM). The stator core 8 is provided at the opposite ends thereof with respective overhanging portions 15 that are not vis-à-vis the magnet 2. As a result, the magnetic flux is prevented from flowing into the stator core 8 through the axial end faces 8a thereof. In other words, the magnetic flux mostly flows into the stator core 8 through the front ends of the teeth. As a result, the pseudo-multi-slot effect produced by the auxiliary grooves is efficiently boosted to reduce cogging and other problems.
    Type: Grant
    Filed: November 24, 2003
    Date of Patent: May 24, 2005
    Assignee: Mitsuba Corporation
    Inventor: Masayuki Okubo
  • Patent number: 6858956
    Abstract: A rotor (17, 31, 71, 91, 101, 121, 131, 141, 201, 401) of a motor (13, 51) is provided with a rotation shaft (21, 59, 410) and a plurality of magnets (15, 53, 75, 105, 210A, 210B, 411) on a circular periphery. Plates (25, 25A, 25B, 25C, 63, 77, 220, 300, 430) made of magnetic materials are provided so that each of which is magnetized by leakage flux of a corresponding magnet (15, 53, 75, 105, 210A, 210B, 401). The plates (25, 25A, 25B, 25C, 33, 63, 77, 107, 220, 300, 430) are disposed along a circular path such that a maximum flux density is formed at both peripheral ends. A magnetic sensor (27) outputs a signal in response to the variation of a flux density on the circular path.
    Type: Grant
    Filed: February 8, 2001
    Date of Patent: February 22, 2005
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Yuki Nakajima
  • Patent number: 6849982
    Abstract: A toroidal AC generator includes an outer casing and an annular stator core of ferromagnetic material which is encased in a hollow annular cover of plastics material and which is fixed to the casing between the discs of a twin disc rotor. Each rotor disc carries a circular array of alternately polarised permanent magnets which face the stator core. The hollow annular cover is a two-part moulding and is formed of radially inner and outer ring portions which are joined by circular arrays of radial ribs which extend across the opposed radial faces of the annular core and form open-ended radial passages for the electrical phase windings which are wound around the cover. The ribs project radially beyond the radially outer ring portion and form hooks around which a winding may be retained temporarily during winding.
    Type: Grant
    Filed: May 2, 2002
    Date of Patent: February 1, 2005
    Assignee: Newage International Limited
    Inventors: Lawrence Haydock, Nazar Al-Khayat, Stephen Frederick Allen, John Ernest Clive Bean, Neil Lovell Brown, Jeremy Owen Dowdall, Cleveland Mills
  • Patent number: 6803691
    Abstract: An electrical machine comprises a magnetically permeable ring-shaped core centered on an axis of rotation and having two axially-opposite sides. Coils are wound toroidally about the core and disposed sequentially along the circumferential direction. Each coil includes two side legs extending radially alongside respectively sides of the core. Coil-free spaces exist between adjacent side legs. A bracket has first and second side flanges that are connected by a bridging structure and respectively abut the first and second sides of the coil.
    Type: Grant
    Filed: July 7, 2003
    Date of Patent: October 12, 2004
    Inventor: Mitchell Rose
  • Patent number: 6803738
    Abstract: Magnetic forces are used as a controlled actuation mechanism to move and position objects of interest. In one embodiment, a first spherical surface has at least one magnetic positioner attached. A second spherical surface is positioned to move relative to the first spherical surface. A plurality of controlled electromagnets are spaced about the second spherical surface. Control logic energizes at least one of the controlled electromagnets to create magnetic interaction with at least one magnetic positioner to move the first spherical surface relative to the second spherical surface.
    Type: Grant
    Filed: October 12, 2001
    Date of Patent: October 12, 2004
    Assignee: Clarity, LLC
    Inventor: Gamze Erten
  • Patent number: 6776590
    Abstract: Dynamo electric machines and stators for use in such machines are provided. The stators comprise plates configured to be substantially flat and a plurality of spaced apart projections or teeth extending away from the plate and, together with the plate defining a plurality of slots therebetween. The stators comprise masses of metal particles. Using stators made from such metal particles provides enhanced machine efficiency, which is believed to be because of reduced eddy current effects in the stator. Motors including rotors having generally flat arrays of permanent magnetic poles and such stators which are spaced apart from and generally facing the permanent magnetic poles and have a plurality of magnetic windings, and pumps powered by such motors are included within the scope of the present invention.
    Type: Grant
    Filed: February 15, 2002
    Date of Patent: August 17, 2004
    Assignee: SHURflo Pump Manufacturing Company, Inc.
    Inventors: David J. Cooper, Gary F. McKee, Mike Saveliev, Patrick J. Weaver
  • Publication number: 20040135465
    Abstract: An axial field electric machine having an improved efficiency includes a number of magnetic elements (e.g., as a rotor) as annular disks magnetized to provide multiple sector-shaped poles. Each sector has a polarity opposite that of an adjacent sector, and each sector is polarized through the thickness of the disk. The poles of each disk are aligned with opposite poles of each adjacent magnet. Metal members adjacent the outermost disks contain the flux. The axial field electric machine also includes one or more conductor elements (e.g., as a stator) which include a number of conductor phases that traverse the flux emanating between poles of axially adjacent magnetic elements.
    Type: Application
    Filed: December 29, 2003
    Publication date: July 15, 2004
    Inventors: Stephen H. Smith, Yuval Shenkal
  • Patent number: 6717313
    Abstract: An energy conversion magnetic circuit is constituted with magnet pole pieces of magnets or armatures which are in parallel with respect to the shaft to obtain a dynamic force or an electromotive force. The magnetic circuit for a generator or an electric motor has a rotating shaft, a plurality of supporters fixedly mounted in a perpendicular direction to the circumference of the rotating shaft, a plurality of rotors arranged in parallel with respect to the shaft on each end of the plurality of supporters to be rotated by attraction force and repulsion force of a magnetic field, and a plurality of armatures having a coil wound on the body thereof. The coil is mounted at an interval outside the rotors and receives induced alternate magnetic flux of the rotors to generate a rectangular wave electromotive force or to obtain a high torque with input of electrical energy.
    Type: Grant
    Filed: November 15, 2000
    Date of Patent: April 6, 2004
    Assignee: Enertec Korea Co., LTD
    Inventor: Youn Soo Bae
  • Patent number: 6707208
    Abstract: An electric motor utilizing permanent magnets, wherein the permanent magnets produce a flux circuit in a first direction and shunt elements whereby the magnets and shunt elements rotate relative to each other wherein the shunt elements sequentially interrupt the magnet flux circuit to minimize generated flux circuits tending to rotate the motor in a direction opposite to the primary direction of motor rotation.
    Type: Grant
    Filed: May 12, 2003
    Date of Patent: March 16, 2004
    Inventors: Gary L. Durham, Harold S. Durham
  • Patent number: 6605883
    Abstract: Disclosed is a multi-phase flat-type PM stepping motor comprising a first motor unit having a first stator unit and a first rotor unit, and a second motor unit having a second stator unit and a second rotor unit. The first stator unit has a plurality of air-core coils that are radially arranged on a first isolating magnetic disc. The first rotor unit has a plurality of permanent magnets that are alternatively magnetized in N-pole and S-pole and radially arranged on a second magnetic disc with a predetermined air gap with respect to the coil surface of the first stator unit. In the same manner, the second stator unit has a plurality of air-core coils that are radially arranged on a third isolating magnetic disc, and the second rotor unit has a plurality of permanent magnets arranged on a fourth magnetic disc. The first and second motor units are coaxial and symmetric with each other about a non-magnetic disc arranged therebetween.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: August 12, 2003
    Assignee: Japan Servo Co., Ltd.
    Inventors: Kouki Isozaki, Yuichi Tsuda, Junji Rokunohe
  • Publication number: 20030090167
    Abstract: A rotary electric machine includes a stator core having a plurality of slots disposed at an inner periphery, an armature winding disposed in the slots and a rotor disposed inside the inner periphery of the stator. The rotor includes a first rotor portion and a second rotor portion, which are disposed magnetically in parallel with each other. The first rotor portion has a plurality of permanent-magnet poles, and a second rotor portion has a plurality of salient induction poles.
    Type: Application
    Filed: December 16, 2002
    Publication date: May 15, 2003
    Applicant: DENSO CORPORATION
    Inventors: Hiroaki Kajiura, Masahiro Seguchi
  • Publication number: 20030052553
    Abstract: A stepping motor includes a first motor unit having a first stator unit and a first rotor unit and a second motor unit having a second stator unit and a second rotor unit. The first stator unit has air-core coils that are radially arranged on a first isolating magnetic disc. The first rotor unit has permanent magnets that are alternatively magnetized in N-pole and S-pole and radially arranged on a second magnetic disc with a predetermined air gap to the first stator unit. Similarly, the second stator unit has air-core coils on a third isolating magnetic disc and the second rotor unit has permanent magnets on a fourth magnetic disc. The first and second stator units are fixed to the different sides of a non-magnetic disc. The first and second rotor units are fixed to a rotation axis and face each other across the first and second stator units.
    Type: Application
    Filed: September 13, 2002
    Publication date: March 20, 2003
    Applicant: JAPAN SERVO CO., LTD.
    Inventors: Kouki Isozaki, Shoji Ohiwa
  • Patent number: 6455969
    Abstract: A single-stator-double-rotor rotating motor has one upper-layer rotor, one intermediate-layer armature and one lower-layer rotor. The upper-layer rotor and lower-layer rotor are embedded with the same number of magnets to form a magneto type magnetic pole, stator electrodes of the same number as the number of magnets are disposed on the intermediate-layer armature to form an electro type magnetic pole. A skew symmetry exists between an upper-layer rotor and a corresponding lower-layer rotor, and the upper-layer rotor and the lower-layer rotor are rotated in opposite directions by commutation of the current flowing through exciting coils of the stator electrodes every T/N of time, wherein T is a rotation period of the upper-layer rotor, and N is the number of the magnets.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: September 24, 2002
    Assignee: Chung-Shan Institute of Science & Technology
    Inventor: Ping-Ho Chen