Permanent Magnet Rotor Patents (Class 310/156.01)
  • Publication number: 20100059056
    Abstract: A brushless DC motor including a rotor, a magnet provided to the rotor, a pair of bearings to rotatably support the rotor, a stator assembly that at least partly surrounds the rotor and magnet thereof and adapted to control movement of the rotor, and a bearing tube having an exterior surface and an interior surface that defines a tube interior. The stator assembly is provided along the exterior surface of the tube and the bearings are provided along the interior surface of the tube to support the rotor and magnet within the tube interior. The motor has sample application for use in PAP devices for delivery of positive airway pressure therapy for users or patients.
    Type: Application
    Filed: October 24, 2007
    Publication date: March 11, 2010
    Applicant: RedMed Motor Technologies Inc.
    Inventors: David B. Sears, Aleksandr Nagorny, Samuel Aziz Mebasser
  • Publication number: 20100052438
    Abstract: An accessory drive system which is capable of preventing the driving efficiency thereof from being lowered and achieving simplified construction, and reduction of the size and manufacturing costs. The system has a rotating machine including a first rotor, a second rotor, and a stator. The first rotor is formed by magnetic poles circumferentially arranged, with each two adjacent ones having different polarities. The stator has an armature row for generating a rotating magnetic pole that circumferentially rotates, between the armature and magnetic pole rows. The second rotor is formed by soft magnetic material elements circumferentially arranged with space, and disposed between the magnetic pole and armature rows. A ratio between the number of the armature magnetic poles, that of the magnetic poles, and that of the soft magnetic material elements is set to 1:m:(1+m)/2(m?1.0).
    Type: Application
    Filed: August 17, 2009
    Publication date: March 4, 2010
    Applicant: HONDA MOTOR CO., LTD.
    Inventors: Shigemitsu AKUTSU, Satoyoshi OYA, Kota KASAOKA, Noriyuki ABE
  • Publication number: 20100052452
    Abstract: A rotor for an electric motor (10) includes a magnetic assembly (12) formed into a ring-shaped plate form, a rotor disc (11) for holding an inner periphery of the magnet assembly, and an outer peripheral ring (13) for holding an outer periphery of the magnet assembly. The magnet assembly is composed of first and second main magnets (12A-1, 12A-2) having magnetizations directions that are oriented perpendicularly and having orientations that are opposite one another, and first and second submagnets (12B-1, 12B-2) having magnetization directions that are oriented perpendicularly in a circumferential direction and having orientations that are opposite one another. At least one group of magnets selected from the main magnets and the submagnets has a wedge-shaped planar part. The planar parts of the first and second main magnets and first and second submagnets form the same plane of rotation. The magnets are arranged so that the magnetization directions of adjacent magnets are perpendicular to one another.
    Type: Application
    Filed: February 8, 2007
    Publication date: March 4, 2010
    Inventors: Tsutomu Yoshino, Koichi Oku, Hisashi Murakami
  • Publication number: 20100045131
    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: April 3, 2008
    Publication date: February 25, 2010
    Inventors: Hu Li, Yuichi Yoshikawa, Hiroshi Murakami
  • Publication number: 20100026228
    Abstract: A dynamoelectric machine which operates in a constant power mode.
    Type: Application
    Filed: July 30, 2008
    Publication date: February 4, 2010
    Inventor: Richard A. Himmelmann
  • Publication number: 20100026105
    Abstract: A mobile data storage device is configured in the manner of a data storage card, or a data storage stick. The mobile data storage device can include at least one electrical coil (7), and energy storage (6), a data storage (1), at least one interface unit (3), and at least one permanent magnet (8). The at least one interface unit (3) is configured for the output or the receiving of data that is stored, or that can be stored, in the data storage (1). The energy storage (6) can be inductively charged by a magnetic alternating field, which can be generated by displacing the at least one permanent magnet (8) in a region of the electrical coil (7). At least one of the at least one interface unit (3) is electrically coupled to the energy storage for the energy supply thereof.
    Type: Application
    Filed: October 15, 2007
    Publication date: February 4, 2010
    Inventors: Jens-Uwe Busser, Martin Otto
  • Patent number: 7652549
    Abstract: A magnetic latch includes a stator having first and second permanent magnets disposed on either side of a center portion. Each of the first and second permanent magnets has at least two associated poles. A rotor has at least one magnetic region. The rotor is configured for rotation about an axis of the stator between a first latched position and a second latched position.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: January 26, 2010
    Assignee: Honeywell International Inc.
    Inventors: Steve L. Hadden, Paul D. Buchele, David Osterberg
  • Patent number: 7649300
    Abstract: An electromagnetic actuator includes a rotor rotatable within a predetermined angular range, a magnetizing coil, and a yoke having an arcuate surface facing the rotor, and first and second magnetic-pole parts that have mutually different magnetic poles upon energizing the coil. The rotor includes a magnetized rotor part defining the outer peripheral surface of the rotor and magnetized to have different magnetic poles, a non-magnetized driving pin rotatable with the magnetized rotor part, and a protrusion part protruding radially from the rotor and facing the first or second magnetic-pole part while being magnetized to have the same magnetic pole as the outer peripheral surface of the rotor. The surface of the rotor that faces the yoke and that exerts a magnetic action is increased due to the inclusion of the protrusion part, and hence a desired maintaining force and driving torque can be obtained.
    Type: Grant
    Filed: March 21, 2006
    Date of Patent: January 19, 2010
    Assignee: Nidec Copal Corporation
    Inventor: Nobuaki Watanabe
  • Publication number: 20100007230
    Abstract: A spindle motor includes: a stator yoke having a circular cylinder shape; a rotor magnet disposed opposite to the stator yoke with an air gap therebetween; a sheet-like coil disposed at a surface of the stator yoke opposing the rotor magnet; and a bearing structure, wherein the sheet-like coil includes a plurality of individual coils having a spiral-shape and arrayed in a circumferential direction, and a pattern made of a same material as the individual coils and disposed between two adjacent individual coils.
    Type: Application
    Filed: June 9, 2009
    Publication date: January 14, 2010
    Applicant: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Yuuki Takahashi, Miyuki Furuya
  • Publication number: 20100007303
    Abstract: A torquer apparatus generally comprises a reaction-gyro sphere consisting of a concentric assembly of a substantially spherical rotor and a substantially spherical stator. This is implemented in the present invention as a rotor with magnetic poles such that, when radially projected on a concentric octahedron, the same symmetrical pattern is obtained on all faces of said octahedron, the polarity of the poles projected on two adjacent faces of said octahedron being opposite and a stator with at least twenty poles magnetized with coils and such that, when radially projected on a concentric icosahedron, the same symmetrical pattern is obtained on all faces of said icosahedron, said stator being-in nominal position-concentric with said rotor. Real-time measurements, or equivalent information, of the position of the rotor with respect to the stator are obtained together with exported torque from the stator, or the orientation of the rotor with respect to the stator.
    Type: Application
    Filed: March 28, 2007
    Publication date: January 14, 2010
    Inventor: Olivier Chételat
  • Publication number: 20100007232
    Abstract: Disclosed herein is a sintered magnet motor having a sintered magnet rotor, the rotor comprising: a ferromagnetic material comprising iron as a main ingredient to be sintered; a fluorine compound or an oxyfluoride compound formed in the inside of a crystal grain or to a portion of a grain boundary of the ferromagnetic material; and at least one of alkalis, alkaline earth elements, and rare earth elements contained in the fluorine compound or the oxyfluoride compound; a portion of the fluorine compound or the oxyfluoride compound being distributed with a concentration gradient established from the surface to the inside of the ferromagnetic material, and a rare earth element being distributed with a concentration gradient established between the grain boundary surface and the parent phase of the ferromagnetic material, wherein the concentration distribution of the fluorine compound is asymmetrical when viewed from the pole center of the sintered magnet rotor.
    Type: Application
    Filed: May 26, 2009
    Publication date: January 14, 2010
    Applicant: Hitachi Ltd.
    Inventors: Matahiro Komuro, Yuichi Satsu, Yutaka Matsunobu, Takashi Yasuhara
  • Patent number: 7646124
    Abstract: A rotor for a brushless permanent magnet generator/motor comprises a retention slot extending into a rotor flange for receiving a root of a permanent magnet. The retention slot comprises a base extending axially into the rotor flange, a pair of side walls extending radially from the base, and a pair of lugs projecting from the side wall to engage the root to provide radial and tangential retention of the permanent magnet. In other embodiments, the permanent magnet is further restrained in the axial direction by a spring pre-loaded axial retention ring.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: January 12, 2010
    Assignee: Hamilton Sundstrand Corporation
    Inventors: Richard A. Himmelmann, Mohammad Shahamat
  • Patent number: 7646126
    Abstract: A permanent-magnet switched-flux (PMSF) device has a ferromagnetic outer stator mounted to a shaft about a central axis extending axially through the PMSF device. Pluralities of top and bottom stator poles are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the ferromagnetic outer stator. A ferromagnetic inner rotor is coupled to the shaft and has i) a rotor core having a core axis co-axial with the central axis; and ii) first and second discs having respective outer edges with first and second pluralities of permanent magnets (PMs) mounted in first and second circles, radially outwardly from the rotor core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.
    Type: Grant
    Filed: June 9, 2008
    Date of Patent: January 12, 2010
    Assignee: Board of Regents of the Nevada System of Higher Education on Behalf of the University of Nevada, Reno
    Inventors: Andrzej M. Trzynadlowski, Ling Qin
  • Patent number: 7642689
    Abstract: A rotor includes: a magnet having a circular cylinder shape and having a hole formed through its axial center, wherein the hole has in axial cross section a regular polygonal shape having flat portions and angle portions, and wherein a recess having a truncated cone shape is disposed at an axial end of the magnet such that the recess has its maximum diameter portion located at the axial end and has its minimum diameter portion communicating with the hole; and a shaft fitted in the hole of the magnet, wherein the outer circumference of the shaft makes contact with the flat portions of the hole of the magnet thereby forming a plurality of gaps between the outer circumference of the shaft and the angle portions of the hole of the magnet, and adhesive is filled in the gaps.
    Type: Grant
    Filed: June 17, 2008
    Date of Patent: January 5, 2010
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Takayuki Yamawaki, Hiroyuki Furusaki
  • Publication number: 20090322173
    Abstract: An electromagnetic machine has a moving component, a stationary component, and a support component coupling the moving and stationary components in physical and electromagnetic proximity. The stationary component is a wound coil of insulated, electrically conductive tape defining a side face which has a plurality of spaced apart channels in it. The coil carries an electric current so that its opposite faces are north and south electromagnet pole faces and these pole faces are interrupted with spaced apart channels. The moving component is made up of a plurality of permanent magnets arranged in north-to-south pole alignment sequence and spaced apart. Non-magnetic pole surfaces of the magnets are positioned in close mutual proximity to the coil pole face. Electromotive forces are produced by electromagnetic interaction between the coil channels and the permanent magnet pole faces.
    Type: Application
    Filed: June 25, 2008
    Publication date: December 31, 2009
    Inventor: Dumitru Bojiuc
  • Publication number: 20090309446
    Abstract: An electric arc welding system is powered by a power generator with a rotor assembly circumferentially surrounding a stator assembly. The arc welding system generates a three phase AC current, which is converted into a DC current by a converter. An electrode coupled to the converter receives the DC current, wherein a welding arc is created between the electrode and a workpiece. A controller is coupled to the converter. The controller is operable to apply a control signal to the converter to cause the converter to vary the magnitude of the DC current.
    Type: Application
    Filed: June 13, 2008
    Publication date: December 17, 2009
    Inventors: Terry D. Scott, Johnny L. Scott, Lawrence A. Hash
  • Publication number: 20090260363
    Abstract: A method and device to optimize the cumulative beneficial effect of harvesting all available forms of lost energy, including energy that is lost while a vehicle is in motion (e.g., kinetic, inertia, friction, thermodynamic, and aerodynamic losses). The cumulative energy that is recovered is converted to electrical energy which powers the on-board electrolyzer to produce more hydrogen and oxygen while the system is in operation and stationary. Stationary, passive means of energy, solar, wind, hydro, etc. will also be available to power the electrolyzer. The system also contemplates utilizing passive means of energy to power a non-mobile system which incorporates an internal or external combustion engine in place of a fuel cell.
    Type: Application
    Filed: April 16, 2009
    Publication date: October 22, 2009
    Inventor: Donald Moriarty
  • Publication number: 20090261675
    Abstract: A high efficient magnetic energy shifting device includes at least a magnetism unit consisting of plural induction coils and at least a magnetic element. Each of the induction coils is provided with plural individual coils formed by having wire coaxially wound in a same direction, an opening formed in the center of the individual coils and an induction stage formed around the outer surface of the individual coils. The induction coils are successively arrayed and fixed stably by positioning elements. The magnetic element is located at a position corresponding to a maximal surface of the induction stage so as to create a high voltage in a same unit area or kinetic energy under a low current, achieving a purpose of high efficient energy shift.
    Type: Application
    Filed: April 19, 2008
    Publication date: October 22, 2009
    Inventors: Hsien-Wei Hsiao, Yu-Wei Fan, Kuan-Jung Liu
  • Publication number: 20090261774
    Abstract: A variable-flux motor drive system including a permanent-magnet motor including a permanent magnet, an inverter to drive the permanent-magnet motor, and a magnetize device to pass a magnetizing current for controlling flux of the permanent magnet. The permanent magnet is a variable magnet whose flux density is variable depending on a magnetizing current from the inverter. The magnetize device passes a magnetizing current that is over a magnetization saturation zone of magnetic material of the variable magnet. This system improves a flux repeatability of the variable magnet and a torque accuracy.
    Type: Application
    Filed: July 24, 2007
    Publication date: October 22, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kazuaki Yuuki, Kazuto Sakai, Hiroshi Mochikawa
  • Publication number: 20090256511
    Abstract: A permanent magnet rotor for use in a flux regulated permanent magnet brushless machine is constructed such that the inductance along the direct and quadrature axes is markedly different to provide sensorless position feedback for the rotor.
    Type: Application
    Filed: April 10, 2008
    Publication date: October 15, 2009
    Inventors: Gregory I. Rozman, Jacek F. Gieras
  • Publication number: 20090251020
    Abstract: A permanent magnet (PM) dynamoelectric machine with directly controllable field excitation control comprises: a drive shaft; a PM rotor assembly with multiple PMs arranged around an outer axial periphery of the rotor assembly; a stator assembly comprising a ferromagnetic stator yoke, multiple ferromagnetic stator teeth mounted to the stator yoke with distal ends proximate the outer axial periphery of the rotor assembly separated by an air gap and multiple stator coils mounted between the stator teeth; multiple saturable ferromagnetic shunts, each shunt coupling adjacent distal ends of the stator teeth to shunt air gap magnetic flux ?g generated by the PMs across the air gap through the distal ends of the stator teeth; and multiple saturation control coils, each saturation control coil wrapped about a saturable region of an associated one of the shunts; wherein application of a control current Ic to the control coils at least partially magnetically saturates the shunts to reduce shunting of air gap magnetic fl
    Type: Application
    Filed: April 2, 2008
    Publication date: October 8, 2009
    Applicant: HAMILTON SUNDSTRAND CORPORATION
    Inventors: Jacek F. Gieras, Gregory I. Rozman
  • Publication number: 20090212651
    Abstract: A motor for holding a disk with a mounting opening in place includes a rotor unit including a rotor magnet rotatable about a central axis and a stator unit including a stator arranged opposite to the rotor magnet and a circuit board electrically connected to the stator. Wiring lines of the circuit board include output-side land portions electrically connected to first ends of coils of the stator, a connection-side land portion electrically connected to second ends of the coils forming a neutral point, a connection portion electrically connected to an external power source, output-side wiring portions arranged to electrically interconnect the output-side land portions and the connection portion, and a connection-side wiring portion arranged to electrically interconnect the connection-side land portion and the connection portion. Each of the output-side wiring portions has a width greater than a width of the connection-side wiring portion.
    Type: Application
    Filed: February 25, 2009
    Publication date: August 27, 2009
    Applicant: NIDEC CORPORATION
    Inventors: Takahiro SUGINOHARA, Haruhiko ITO, Toshihide SONODA, Takuya YAMANE
  • Patent number: 7579733
    Abstract: A motor has a rotor core with a plurality of first non-magnetic layers and a plurality of second non-magnetic layers. The rotor core has a plurality of magnets. The first and second non-magnetic layers are positioned to cancel n-th order harmonics. Therefore, a specific order, for example 5-th order and 7-th order, harmonics component of a magnetic flux distribution waveform (induction voltage waveform) is reduced and unnecessary radial force and thrust force is prevented from occurrence, while sufficient magnetic flux is maintained.
    Type: Grant
    Filed: July 5, 2004
    Date of Patent: August 25, 2009
    Assignee: Daikin Industries, Ltd.
    Inventors: Keiji Aota, Kiyotaka Nishijima, Akio Yamagiwa
  • Publication number: 20090206691
    Abstract: A motor includes a rotor core, permanent magnets and non-magnetic layers. The permanent magnets are embedded in the rotor core with each of the permanent magnets defining a pole of the rotor having a pole center and a peripheral edge section, with the peripheral edge section located in a vicinity between the poles and a vicinity of the rotor surface. The non-magnetic layers are located in a vicinity of the rotor surface at a pole center side position with respect to the peripheral edge section of each of the permanent magnets. The peripheral edge sections and the non-magnetic layers are positioned to cancel 5-th or 7-th order harmonics of an induction voltage. The poles are disposed at every approximately constant interval, varying in a constant angle. The peripheral edge sections and the non-magnetic layers are independent from one another, and the rotor core is interposed between them.
    Type: Application
    Filed: April 23, 2009
    Publication date: August 20, 2009
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Keiji AOTA, Kiyotaka NISHIJIMA, Akio YAMAGIWA
  • Publication number: 20090189471
    Abstract: A spindle motor having a stator and a rotor includes: a stator core provided in the stator having salient-poles; a stator coil arranged between the salient-poles; a rotor; and a permanent magnet provided in the rotor. The stator core includes a stack of steel sheets whose salient-poles are formed by etching. The permanent magnet includes a ferromagnetic material consisting mainly of iron. The ferromagnetic material has formed in laminae on a surface thereof a layer of a fluorine compound containing an alkali element, an alkaline earth element or a rare earth element formed in laminae. Near an interface between the ferromagnetic material and the layer of the fluorine compound, iron exists in the layer of the fluorine compound such that a basic crystal structure of the fluorine compound is not changed and the fluorine compound containing the iron exists in the layer of the fluorine compound.
    Type: Application
    Filed: July 29, 2008
    Publication date: July 30, 2009
    Applicant: Hitachi, Ltd.
    Inventors: Hisato Amano, Yuji Enomoto, Matahiro Komuro, Yuichi Satsu, Fumio Tajima
  • Publication number: 20090179517
    Abstract: An electric motor design for hub motors comprises a stator assembly, having an axle, a stator plate sector holder, fixed on the axle, at least one stator sector assembly, mounted on the stator plate holder, and electric coils, would around the plates of the stator plate assembly; and a rotor assembly, having a casing, a rotor magnet retainer assembly, placed inside of the casing, and at least one permanent magnet, mounted on plates of the rotor magnet retainer assembly; wherein the stator sector assembly and/or the rotor magnet retainer assembly have plates which are stacked on top of each other and which are each divided into at least two sectors, saving production cost.
    Type: Application
    Filed: March 24, 2009
    Publication date: July 16, 2009
    Inventors: Chun-Hsien LU, Huan-Lung Gu, Chi-Tang HSU
  • Patent number: 7559996
    Abstract: A rare earth permanent magnet is prepared from a sintered magnet body of a R1—Fe—B composition wherein R1 is a rare earth element inclusive of Y and Sc, by forming a plurality of slits in a surface of the magnet body, disposing a powder on the magnet body surface, the powder comprising an oxide of R2, a fluoride of R3, or an oxyfluoride of R4 wherein each of R2, R3, and R4 is a rare earth element, and heat treating the magnet body and the powder below the sintering temperature in vacuum or in an inert gas.
    Type: Grant
    Filed: July 20, 2006
    Date of Patent: July 14, 2009
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Koji Miyata, Koichi Hirota, Hajime Nakamura, Takehisa Minowa
  • Publication number: 20090174352
    Abstract: A brushless synchronous motor includes a controller producing a plurality of current vectors having different directions, applied to the synchronous motor. The synchronous motor control system includes a sensor for sensing the rotational angle of a synchronous motor, and a computer for generating data describing a plurality of current vectors corresponding to the rotational angle sensed by the sensor. The computer interfaces with a plurality of digital to analogue conversion circuits generating a plurality of control signals. The control signals are applied to amplification circuitry thereby generating a plurality of current vectors to supply the stator coils of the motor. The motor includes two sections of stator coil arrangements; one is arranged interior to the permanent magnets of the rotor, and one is arrange exterior to the rotor.
    Type: Application
    Filed: January 6, 2009
    Publication date: July 9, 2009
    Inventor: Adam Lockhart
  • Publication number: 20090160296
    Abstract: A polyphase electric machine includes a stator impinged by an electromagnetic rotating field, which has a yoke having yoke teeth having at least partially peripheral slots, in which windings generating a magnetic field are situated, and having a rotor rotatable around an axis having permanent magnets, which is peripherally separated from the stator by an air gap, the rotor being fixedly connected to a pulley, the yoke teeth in the stator being assembled into modules, whose number is equal to the current phases or corresponds to their integral multiple, each module including a number of at least one yoke tooth and—in the event of a possible pole pitch of the rotor to slot pitch of the stator ratio of 9/8—yoke teeth of a module directly neighboring one another having opposite magnetic field polarity.
    Type: Application
    Filed: March 2, 2006
    Publication date: June 25, 2009
    Inventors: Stefan Steinbock, Ingolf Groening, Christian Kaehler
  • Publication number: 20090146431
    Abstract: A faucet generator includes a case having water inflow and outflow ports and in which a water supply channel is formed, a rotor vane disposed inside the water supply channel, a magnet which is rotatable integrally with the rotor vane, a bearing which supports a force that the rotor vane receives from a water flow, a coil which produces an electromotive force by a rotation of the magnet, and a yoke having a base part surrounding the coil and a plurality of inductors spaced apart from each other and extending from the base part. The coil is spaced apart from the magnet in an axial direction of a rotation center axis of the magnet and is disposed to face the magnet, the magnet is magnetized on an outer circumferential face which intersects with a plane perpendicular to the rotation center axis, and the inductors are disposed outside the case to face the outer circumferential face of the magnet.
    Type: Application
    Filed: November 1, 2008
    Publication date: June 11, 2009
    Applicant: TOTO LTD.
    Inventors: Naoyuki ONODERA, Tomoko SATO, Masahiro KUROISHI, Takeshi SHIMIZU
  • Publication number: 20090140526
    Abstract: An electrical machine comprising a rotor and a stator is provided. The stator includes a plurality of stator tooth modules configured for radial magnetic flux flow. The stator tooth modules include at least one end plate, and the end plates have extensions for mounting onto a stator frame. The stator is concentrically disposed in relation to the rotor of the electrical machine.
    Type: Application
    Filed: November 29, 2007
    Publication date: June 4, 2009
    Inventors: Patrick L. Jansen, Ronghai Qu, Aniruddha D. Gadre
  • Publication number: 20090133894
    Abstract: An electric impact tightening tool in which the rotation of an output section of an electric motor is transmitted to an impact generation section (P) and impact force generated in the impact generation section (P) causes a main shaft (107) to produce strong torque, where the electric motor is an outer rotor electric motor (M). The outer rotor electric motor (M) has low-speed, high-torque characteristics. In the tool, the impact generation section (P) and a rotor flange (61) at the forward end of the motor (M) are adapted to rotate integrally. The electric impact tightening tool is small sized and lightweight, produces low reaction force, and has durability.
    Type: Application
    Filed: September 6, 2006
    Publication date: May 28, 2009
    Applicant: YOKOTA INDUSTRIAL CO., LTD.
    Inventor: Masaru Mizuhara
  • Publication number: 20090108693
    Abstract: Disclosed is a motor which includes a stator including a plurality of aluminum coils and a rotor. The rotor includes a frame including a magnetic material, and a permanent magnet attached to the frame. The permanent magnet is made of neodymium.
    Type: Application
    Filed: September 23, 2008
    Publication date: April 30, 2009
    Applicant: LG ELECTRONICS INC.
    Inventors: Cha Seung JUN, Byoung Wook MIN
  • Publication number: 20090108712
    Abstract: According to one embodiment of the present invention, an electric machine includes a stator and a rotor. The stator includes a stator pole including a first leg and a second leg, and a gap defined between the first and second legs. The rotor includes a rotor pole. The rotor is configured to rotate relative to the stator such that the rotor pole rotates through the gap defined between the first and second legs of the stator pole. The stator pole includes a laminar stator pole structure including multiple lamination layers.
    Type: Application
    Filed: July 25, 2008
    Publication date: April 30, 2009
    Inventors: Mark T. Holtzapple, George A. Rabroker
  • Patent number: 7521831
    Abstract: A spindle motor, which includes a bearing to rotatably support a rotating shaft, a bearing holder to securely hold the bearing therein, a base to securely support the bearing holder thereon, a thrust washer aligned at the upper end thereof with the upper end of the base in the same horizontal plane and supporting the rotating shaft in a thrusting direction, a thrust washer cover to receive the thrust washer, and a bearing holder support securely installed between the thrust washer cover and the base and supporting the bearing holder. The bearing holder support is secured to the bearing holder and covers both the lower end of the bearing and part of the lower end of the bearing holder. The bearing holder support includes a protrusion inserted into a depression formed on the lower end of the bearing holder and an edge caulked to the base.
    Type: Grant
    Filed: April 3, 2007
    Date of Patent: April 21, 2009
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Viatcheslav Smirnov, Young Sun Yoo, Pyo Kim
  • Patent number: 7504753
    Abstract: According to the disclosed motor, since the motor includes a rotor in which a plurality of core pieces and magnets are alternately arranged in the circumferential direction, magnetic flux of the magnets is prevented from flowing between the core pieces neighbored with each other in the circumferential direction and the leakage of the magnetic flux can be minimized. Since identical polarities of the magnets neighbored with each other in the circumferential direction face each other, the magnetic flux can be concentrated to the respective core pieces. Moreover, since the axial direction of the circumference of the core facing the stator in the circumferential direction is longer than the axial direction of other portions thereof, torque is increased and manufacturing costs are reduced.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: March 17, 2009
    Assignee: LG Electronics Inc.
    Inventors: Sung Ho Lee, Jin Soo Park, Byung Taek Kim
  • Patent number: 7498707
    Abstract: An electric rotation machine for windmill power generation equipped with a stator slot structure having distributed windings and a rotor pole structure having permanent magnets, wherein the number of slots per pole per phase (Nspp) is undividable by 3 times P (where P is the number of poles), and pole width rate Pw obtained by dividing pole piece width Tp by pole pitch Tr at the outermost diameters of the adjoining poles of the rotor is satisfied any of Pw?0.6, 0.67?Pw?0.71, and 0.78?Pw. The distortion factors of induced voltages in a permanent magnet type electrical rotation machine, particularly for windmill power generation, can be reduced.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: March 3, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Mamoru Kimura, Kazumasa Ide, Kazuo Nishihama, Tetsuo Fujigaki, Shuji Mizutani
  • Publication number: 20090051233
    Abstract: A permanent magnet electric generator includes a rotor assembly and a stator assembly. The rotor assembly has axially disposed annular outer and inner rings concentric with an axis of rotation. The inner ring has a radius less than the radius of the outer ring. The inner ring is disposed inside the outer ring. A rotor frame is attached to the inner ring and the outer ring. The rotor frame defines a radial gap between the inner and the outer rings. A rotor hub is concentric with the axis of rotation and is disposed inside the inner ring. The rotor hub is coupled to the inner ring by a hub frame that is mounted on the rotor hub. The rotor hub is adapted to be rotationally coupled to a shaft for rotating the rotor assembly. A plurality of magnets is disposed on the outer ring, each magnet having a north pole and a south pole. The permanent magnets are aligned with the axis of rotation, and adjacent magnets have alternating polarity.
    Type: Application
    Filed: August 20, 2007
    Publication date: February 26, 2009
    Inventors: Terry D. Scott, Johnny L. Scott, Lawrence A. Hash
  • Publication number: 20090033166
    Abstract: The brushless motor includes a stator having a electromagnetic coil and a position sensor; an axis fixed to the stator; and a rotor having a permanent magnet. The rotor rotates around the axis. The rotor is linked to a driven member that is driven by the brushless motor.
    Type: Application
    Filed: July 16, 2008
    Publication date: February 5, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kesatoshi TAKEUCHI, Kazuyoshi NAKAMURA, Mamoru SUGIMOTO
  • Publication number: 20090026865
    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: Application
    Filed: December 12, 2006
    Publication date: January 29, 2009
    Inventors: Keiji Aota, Akio Yamagiwa, Yoshiki Yasuda
  • Publication number: 20090022436
    Abstract: A bearing unit includes a shaft, a tubular bearing member, a planar plate fixed to a lower side of the bearing member and a lubricant filled between the shaft and an inner circumferential surface of the bearing member. In the bearing member, an inner circumferential wall portion is axially downwardly protruding from a lower surface of the bearing member and has a first surface contacting with and extending in a parallel with an upper surface of the plate and a second surface axially spaced apart from the upper surface of the plate. An outer circumferential wall portion is positioned radially outwardly of the second surface. The plate is fixed to the outer circumferential wall portion of the bearing member, and a radial inner side of the inner circumferential wall portion communicates with the outer circumferential wall portion through a gap formed between the second surface and the slate.
    Type: Application
    Filed: July 15, 2008
    Publication date: January 22, 2009
    Applicant: NIDEC CORPORATION
    Inventor: Sakurada Kunio
  • Publication number: 20090015089
    Abstract: A permanent-magnet switched-flux (PMSF) device has a ferromagnetic outer stator mounted to a shaft about a central axis extending axially through the PMSF device. Pluralities of top and bottom stator poles are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the ferromagnetic outer stator. A ferromagnetic inner rotor is coupled to the shaft and has i) a rotor core having a core axis co-axial with the central axis; and ii) first and second discs having respective outer edges with first and second pluralities of permanent magnets (PMs) mounted in first and second circles, radially outwardly from the rotor core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.
    Type: Application
    Filed: June 9, 2008
    Publication date: January 15, 2009
    Applicant: University of Nevada Reno
    Inventors: Andrzej M. Trzynadlowski, Ling Qin
  • Publication number: 20090009019
    Abstract: Having a stator core including a yoke, a plurality of inside teeth, and a plurality of outside teeth, an inside rotor, and an output rotor, the inside slot open angle/inside pole angle and the outside slot open angle/outside pole angle are determined so that the inside cogging torque due to rotation of the inside rotor and the outside cogging torque due to rotation of the outside rotor may cancel each other in inverted phases. Plural combinations are provided so that the amplitude of inside cogging torque and the amplitude of outside cogging torque due to rotation of outside rotor maybe approximate values in inverted phase, and the combination of the highest combined voltage value of the both induced voltage is selected.
    Type: Application
    Filed: April 10, 2008
    Publication date: January 8, 2009
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hu LI, Yuichi Yoshikawa, Hiroshi Murakami
  • Publication number: 20090001835
    Abstract: An axial air gap type electric motor is constructed such that even if a relatively large force is added in the vertical direction to the rotor output, the bearings are protected against damage. The axial air gap type electric motor includes a stator and two rotors each of which is configured almost with a discoid shape and which are arranged as facing one another on a common rotation axle with a fixed gap being present therebetween. The stator has a stator core comprising multiple pole members connected annularly. One of the bearings for fixing the rotor output axle is installed inside the stator configured annularly and another bearing is installed on the rotor output axle between the outside of said rotor and the load connected.
    Type: Application
    Filed: November 14, 2007
    Publication date: January 1, 2009
    Inventors: Tomonori Kojima, Toshiaki Tanno, Ken Maeyama, Hirokazu Matsuzaki
  • Publication number: 20080315704
    Abstract: The invention relates to a permanently excited synchronous machine (51) comprising a stator (53) and a rotor (55). Preferably, the stator (53) comprises a three-phase current winding and the rotor (55) comprises permanent magnets. The stator (53) comprises 42 slots (27) and 42 teeth (29). Each second tooth (29) is wound with a coil (39). The rotor (55) comprises 26 magnetic poles. The permanently excited synchronous machine can be configured in such a way that the useful pole pair is a prime number.
    Type: Application
    Filed: September 5, 2005
    Publication date: December 25, 2008
    Applicant: Siemens Aktiengesellschaft
    Inventor: Rolf Vollmer
  • Publication number: 20080309205
    Abstract: A clean engine for transportation, generators, and other applications. It comprises a series of alternating support wheel assemblies and magnet wheel assemblies that are propelled in a consistent pattern by battery powered electromagnets. The engine comprises at least one support wheel assembly and at least one magnet wheel assembly. The support wheel assemblies and magnet wheel assemblies are aligned in a specific pattern along a main shaft that is supported on each end by sealed bearings mounted in a nonmagnetic housing.
    Type: Application
    Filed: June 14, 2007
    Publication date: December 18, 2008
    Inventor: Richard Redinbo
  • Publication number: 20080303370
    Abstract: Permanent magnet motors with improved torque ripple and methods for designing the same have been provided. The permanent magnet motor can include a stator having a hollow core and defining a plurality of slots; a winding disposed in each of the slots; a rotor rotatably disposed inside the hollow core of the stator; and a plurality of permanent magnets supported by the rotor. Each of the slots has a slot opening, and at least one of the slot openings can be off-center with respect to the respective slot.
    Type: Application
    Filed: June 7, 2007
    Publication date: December 11, 2008
    Inventors: Khwaja M. Rahman, Peter J. Savagian, Matthew D. Laba
  • Publication number: 20080296992
    Abstract: A three-phase electrical drive machine is described, comprising a static primary part (2) having a sequence of stator grooves (3), in which stator windings (4) of the three phases (U, V, W) are positioned in such a manner that an electric current through the stator windings (4) generates primary part magnetic poles, and a secondary part (5), which is movable on a predefined movement path in relation to the primary part (2) and on which permanent magnets (6) are positioned in such a manner that one of each of their poles faces toward the primary part (2), resulting in a sequence of secondary part magnetic poles in the movement direction, a movement of the secondary part (5) on the movement path being caused by interaction of the primary part magnetic poles, which result from the flow of current, with the secondary part magnetic poles.
    Type: Application
    Filed: September 5, 2006
    Publication date: December 4, 2008
    Inventor: Michael Militzer
  • Publication number: 20080298986
    Abstract: In a method for assembling an electric compressor which contains a rotor having built-in magnets, magnets in a pre-magnetization state are inserted into a plurality of slots of a magnetizing jib made with a nonmagnetic material. After magnetizing the magnets, the magnetizing jib is fitted to the rotor to have the magnets transferred into magnet slots.
    Type: Application
    Filed: July 8, 2008
    Publication date: December 4, 2008
    Inventors: Tsuyoshi ISHIDA, Yasuhisa TAKAHASHI, Hidetoshi NISHIHARA
  • Publication number: 20080290751
    Abstract: A brushless permanent magnet motor with unequal-width slots and its manufacturing method completes a design of a regular motor with equal-width slots, employs a single-layer centralized winding, increasing the width equally on left and right sides of a first type of teeth wound with a coil until a width Wt3 of a tooth tip equals to a width Wp of a magnetic pole, such that the stator slot opening shifts towards a second type of teeth with no coil, increasing a width of a first type of teeth with a coil equally on left and right sides until a coil pitch equals to a width Wp of a magnetic pole or a motor angle equals to 180°, and decreasing a width Wt2 of a second type of teeth with no coil equally on both left and right sides until a slot area Sa2 is greater than the original slot area Sa1 of a regular motor with equal-width slots to improve the motor efficiency and reliability for a variable speed operation.
    Type: Application
    Filed: May 16, 2008
    Publication date: November 27, 2008
    Inventors: Chang-Chun Hwang, Shih-Ping Cheng, Ping-Lun Li, Wen-Yen Shen