Induction Patents (Class 310/166)
  • Patent number: 7538469
    Abstract: Synchronous motors according to the invention operate at higher efficiency, with lower cost, reduced mass and reduced cogging. Magnet dimensions are selected that reduce cogging forces to a negligible amount even though there are fewer slots than normal. Optionally, it is possible to use non-overlapping windings with deeper and open slots. The approach is applicable to both rotary and linear motors and motors using either permanent magnets or electromagnets in the field structure. It is particularly relevant to linear or rotary motors that have a large air gap, and to small motors that must deliver a high ratio of thrust or torque to motor mass.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: May 26, 2009
    Assignee: MagneMotion, Inc.
    Inventors: Richard D. Thornton, Tracy M. Clark
  • Patent number: 7535150
    Abstract: Disclosed is a centrifugal turbine gas blower with foil bearings for use with a fast axial flow laser. The blower utilizes variable components in order to operate at different speeds for multiple applications. In addition, a bypass load has been incorporated to avoid a surge condition. The blower utilizes foil bearings that are self-lubricating in order to achieve improved efficiency and maximized speeds during operation. The bearings are designed with a bump layer that provides damping for pre-load. Additionally, the backplate of the thrust assembly contains holes in order to reduce the thrust load and to balance the force on the impeller.
    Type: Grant
    Filed: May 8, 2006
    Date of Patent: May 19, 2009
    Assignee: PRC Laser Corporation
    Inventor: Walter Wilson
  • Patent number: 7514832
    Abstract: An electric motor having a single field rotor wherein the flux within the rotor is generated by magnetic means located at the end regions of the motor housing such that the flux within the motor rotor maintains a constant polarity.
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: April 7, 2009
    Assignee: Tri-Seven Research, Inc.
    Inventors: Gary L. Durham, Harold S. Durham
  • Patent number: 7511395
    Abstract: A hybrid induction motor comprises a stator fixedly installed in a casing, an induction rotor rotatably inserted into a center of the stator and having a shaft at a center thereof, a first synchronous rotor slid in a longitudinal direction of the shaft between the stator and the induction rotor and free-rotatably installed in a circumferential direction of the shaft, and a second synchronous rotor facing the first synchronous rotor, slid in a longitudinal direction of the shaft between the stator and the induction rotor, and free-rotatably installed in a circumferential direction of the shaft.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: March 31, 2009
    Assignee: LG Electronics Inc.
    Inventors: Seung Do Han, Hyoun Jeong Shin, Jae Hong Ahn
  • Patent number: 7501735
    Abstract: A self-magnetized motor includes a stator adapted to rotate by electromagnetic interaction with a rotator, a plurality of slot teeth formed on and surrounding a through-hole of the stator, and an excitation pole adjacent at least one slot tooth having fewer projections than remaining ones of the slot teeth. The projections are formed on ends of the slot teeth facing the through-hole of the stator. According to one non-limiting embodiment, the excitation pole may be formed between two slot teeth having fewer projections.
    Type: Grant
    Filed: December 28, 2006
    Date of Patent: March 10, 2009
    Assignee: LG Electronics Inc.
    Inventors: Moo Hong Seo, Jin Soo Park, Sung Ho Lee, Jang Ho Shim, Jae Min Kim, Jae Hak Choi
  • Publication number: 20090026869
    Abstract: A transverse flux machine or transverse flux reluctance machine with a primary part, which is provided with a coil arrangement equipped with at least one phase module (100; 600), and a secondary part (300; 400; 410, 800), which moves in relation to the primary part, in which a phase module (100; 600) has a phase module winding (606), a phase module back iron (101; 601), and at least one pair of pole elements (102; 602) that constitutes a pole element pair (105; 605); each pole element (102; 602) has a pole element back iron (103; 603) extending from the phase module back iron (101; 601) in perpendicular fashion and a pole element leg (104; 604) extending parallel to the phase module back iron (101; 601); the phase module back iron (101; 601), together with each pole element (102; 602), forms a respective, essentially C-shaped cross section; the phase module winding (606) is at least partially situated inside the essentially C-shaped cross section; the pole elements (102; 602) of the at least one pole element
    Type: Application
    Filed: July 16, 2008
    Publication date: January 29, 2009
    Inventors: Christian Kaehler, Ingolf Groening
  • Publication number: 20090021093
    Abstract: Electric motors, for example wet rotor motors, include a rotor, a winding support, and plurality of electrical windings surrounding the rotor. In some implementations, the winding support is a rotor housing, e.g., the can of a wet rotor motor. The windings define the stator of the motor.
    Type: Application
    Filed: July 17, 2007
    Publication date: January 22, 2009
    Applicant: TACO, INC.
    Inventor: Michael McNamara
  • Patent number: 7459814
    Abstract: The hybrid induction motor includes a housing; a stator installed in the housing and having a stator core portion and a stator coil portion; a rotor coupling body having a rotary shaft rotatably installed in at the housing, a cage rotor portion rotating integrally with the rotary shaft, and a permanent magnet rotor portion coupled to a circumference of the cage rotor portion with a certain air gap so as to rotate freely with respect to the rotary shaft; and a reverse rotation preventing switch, when the rotary shaft rotates reversibly, coming in contact with the permanent magnet rotor portion which is moved along the shaft by thrust generated by the rotor coupling body and cutting off power being supplied to the stator coil portion.
    Type: Grant
    Filed: January 5, 2006
    Date of Patent: December 2, 2008
    Assignee: LG Electronics Inc.
    Inventors: Dong-Il Lee, Seung-Do Han, Hyoun-Jeong Shin, Jae-Hong Ahn, Seung-Suk Oh
  • Patent number: 7459815
    Abstract: An induction motor having a reverse-rotation preventing function, comprises: a stator provided with a winding coil generating flux by a current; an induction rotor provided with a cage and rotatably inserted in the stator, wherein a rotary shaft is coupled to its inside; a synchronous rotor provided with a permanent magnet and rotatably coupled between the stator and the induction rotor; an induction-force generating unit generating a force for moving the synchronous rotor in an axial direction; and a rotation preventing unit preventing a reverse rotation by fixing the synchronous rotor moved by the induction-force generating unit at the time of reverse rotation of the synchronous rotor.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: December 2, 2008
    Assignee: LG Electronics Inc.
    Inventors: Seung-Do Han, Hyoun-Jeong Shin, Jae-Hong Ahn, Seung-Suk Oh, Dong-Il Lee
  • Patent number: 7459822
    Abstract: An electric machine, such as a switched reluctance motor (SRM), having one or more transverse flux axes is described. The rotor and stator of the electric machine have more than one phase, not necessarily of even number. Flux guidance regions within the stator are angularly and spatially located such that they may be transverse, or not coinciding with, the plane perpendicular to the axis of shaft rotation. The flux guidance regions are composed so as to contain a magnetic field whose flux is guided in either a loop or coupled configuration. In the loop configuration, multiple flux guidance paths that are able to operate simultaneously exist within each chuck arrangement. In the coupled configuration, a single primary flux guidance path exists within the chuck arrangement. Transverse flux guidance allows for the removal and replacement of stator windings without significant disassembly or removal of the motor.
    Type: Grant
    Filed: May 13, 2005
    Date of Patent: December 2, 2008
    Inventors: Weston C. Johnson, Richard M. Currie
  • Patent number: 7439644
    Abstract: A hybrid induction motor comprises a stator fixedly installed in a casing, an induction rotor rotatably inserted into a center of the stator and having a shaft at a center thereof, a first synchronous rotor installed between the stator and the induction rotor in a circumferential direction of the shaft so as to be freely rotatable, and a second synchronous rotor facing the first synchronous rotor in a longitudinal direction of the shaft and installed between the stator and the induction rotor so as to be freely rotatable.
    Type: Grant
    Filed: January 5, 2006
    Date of Patent: October 21, 2008
    Assignee: LG Electronics Inc.
    Inventors: Jeong-Chul Kim, Dong-Il Lee, Seung-Do Han, Hyoun-Jeong Shin, Jae-Hong Ahn, Seung-Suk Oh
  • Publication number: 20080238237
    Abstract: An induction machine has a stator and rotor. The stator comprises teeth and slots and stator winding disposed in the slots. The rotor comprises a rotor core having teeth and slots and a rotor-conductor disposed in the rotor slots. Both of the stator core and rotor core are made of laminated steel sheets, and the teeth and slots made of steel sheets are formed by etching.
    Type: Application
    Filed: February 6, 2008
    Publication date: October 2, 2008
    Inventors: Kazuo Nishihama, Teruyoshi Abe, Yoshihisa Ishikawa, Hiroyuki Mikami
  • Publication number: 20080238236
    Abstract: A switched reluctance machine is provided. The switched reluctance machine has a rotor including a rotor core, where the rotor core includes multiple laminated sheets, each of the laminated sheets including multiple ferromagnetic regions and multiple non-ferromagnetic regions formed of a single material. The ferromagnetic and the non-ferromagnetic regions are alternately arranged such that the ferromagnetic regions form multiple rotor teeth and the non-ferromagnetic regions define multiple non-ferromagnetic gaps between the rotor teeth.
    Type: Application
    Filed: March 27, 2007
    Publication date: October 2, 2008
    Applicant: GENERAL ELECTRIC COMPANY
    Inventor: Ayman Mohamed Fawzi El-Refaie
  • Patent number: 7425808
    Abstract: A rotor is provided with slits each of which serves as a flux barrier blocking a magnetic flux. A direction shown by an arrow is a forward direction along which the rotor rotates when a vehicle moves forward. Each of the slits has a width tapering down from a trailing position toward a leading position with respect to the forward direction. The rotation in a reverse direction opposite to the forward direction shown by the arrow causes larger magnetic flux linkage than the rotation in the forward direction, and hence generates high torque and high counterelectromotive force. Therefore, in the reverse direction, the rotor cannot serve as a motor to produce an output unless high voltage is applied thereto. Accordingly, the torque generated in the reverse direction is used for regenerative operation. It is thereby possible to provide a vehicle drive system capable of exhibiting performance in a well-balanced manner between power running and regenerative operation, and a vehicle provided with the same.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: September 16, 2008
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Munehiro Kamiya
  • Publication number: 20080203846
    Abstract: A horizontal axis washing machine includes a clothing receptacle rotated by a 4 pole rotor. A 36 slot stator having an interior bore with an interior diameter receives the 4 pole rotor in magnetic coupling relation and capable of operating within a flux weakening range of at least 5:1. The stator has a ratio of an interior diameter to a minimum exterior diameter greater than or equal to 0.63:1.
    Type: Application
    Filed: February 28, 2007
    Publication date: August 28, 2008
    Applicant: EMERSON ELECTRIC CO.
    Inventors: Keith I. Hoemann, Gary E. Horst
  • Publication number: 20080179981
    Abstract: A high phase order induction machine wound and permitted by coil symmetry to operate at fewer than the magnetically optimal number of poles is constrained by symmetry to be a two pole machine and be capable of operating on odd harmonics only, but with back-iron, end rings, and rotor core optimized for 10 pole operation, might be used normally in ‘5th harmonic’ mode, with ‘7th harmonic’ utilized to engage the ‘mesh effect’. Such a machine thus appears to be operating in the ‘1.4 harmonic’. A high phase order induction machine driven by a second harmonic drive, in which a symmetry imposed by full span windings is broken. This may be most simply accomplished through the use of short pitch windings. Other possible approaches include using non-wound slot drive, and using toroidal windings which localize coils to individual slots.
    Type: Application
    Filed: January 9, 2008
    Publication date: July 31, 2008
    Inventor: Jonathan Sidney Edelson
  • Patent number: 7385329
    Abstract: In electric machines, core losses limit, at high fundamental frequency, the permissible full-load power. The aim of the invention is to develop a design which enables a high power density at high magnetic reversal frequencies and which is easy to produce. To this end, the primary part comprises coils which, for the majority of their length, run in the direction of movement and which are surrounded in this area on three sides by soft magnetic material. In the direction of movement, at least two coils are arranged one behind the other. Coils of different phase are arranged perpendicular to the direction of movement inside different running tracks. In the secondary part, at least two oppositely magnetized hard magnets with three collector segments, which are flatly adjacent in a manner that is perpendicular to the direction of movement, form magnet poles having a high flux concentration.
    Type: Grant
    Filed: March 4, 2003
    Date of Patent: June 10, 2008
    Inventor: Wolfgang Hill
  • Publication number: 20080124233
    Abstract: A turbocharger comprises a turbine wheel and a compressor wheel mounted to a turbocharger shaft. An electric induction motor is provided for assisting rotation of the compressor wheel in predetermined circumstances. The motor comprises a fixed stator having motor field coils which generate a rotating magnetic field when energised by an AC control signal which induces eddy current flow in a rotor to generate a rotor magnetic field which in turn interacts with the stator magnetic field producing torque in the rotor.
    Type: Application
    Filed: August 20, 2007
    Publication date: May 29, 2008
    Inventor: Edward Spooner
  • Patent number: 7342339
    Abstract: A reluctance machine includes a stator having a stator core. The stator core includes a central bore and a plurality of stator poles extending inwardly from the stator core. Each of the stator poles includes a stator pole face. The reluctance machine further includes a rotor having a plurality of rotor poles. Each of the rotor poles includes a rotor pole face. Each of the rotor pole faces includes a first portion, a second portion that is radially inwardly stepped with respect to the first portion to create a non-uniform air gap between the rotor pole face and a corresponding stator pole face, and a protrusion located at an edge of the second portion of the rotor pole face.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: March 11, 2008
    Assignee: Shop Vac Corporation
    Inventors: Neil N. Norell, Mark E. Baer
  • Publication number: 20080001491
    Abstract: A machine includes a shaft adapted to rotate about a longitudinal axis and formed of a magnetic material and a rotor assembly rotationally engaged with the shaft The rotor assembly includes a pair of rotor disks comprising a magnetic material, each of the rotor disks having a number of magnetic poles, the magnetic poles being spaced apart circumferentially. The rotor disks are coupled to the shaft for rotation about the shaft and generation of a rotating permeance wave. The machine further includes a stator assembly that includes a magnetic core stator disposed between the rotor disks, a number of armature windings supported on the magnetic core stator, and a stationary superconducting field coil disposed between the magnetic core stator and the shaft. The stationary superconducting field coil is configured as a stationary magneto-motive force (MMF) source for the rotating permeance wave produced by the rotor assembly to produce a rotating magnetic field.
    Type: Application
    Filed: June 30, 2006
    Publication date: January 3, 2008
    Inventors: Ronghai Qu, James William Bray
  • Publication number: 20080001495
    Abstract: A machine includes a stator assembly that includes a stator yoke, a pair of armature coils mechanically coupled to the stator yoke, and a stationary superconducting field coil. The stator yoke comprises a magnetic material. The machine further includes a shaft rotatably mounted in the stator yoke, the shaft comprising a non-magnetic material. The machine further includes a rotor assembly rotationally engaged with the shaft. The rotor assembly includes a rotor disk extending between the armature coils, the rotor disk having an inner portion and an outer portion. The outer portion of the rotor disk includes a number of circumferentially-spaced, magnetic poles. The rotor disk is coupled to the shaft for rotation about the shaft and generation of a rotating permeance wave.
    Type: Application
    Filed: June 30, 2006
    Publication date: January 3, 2008
    Inventors: Ronghai Qu, James William Bray
  • Publication number: 20070296313
    Abstract: A self-generating system for an exercise apparatus including a flywheel having a flange with a plurality of permanent magnets fixed on the circumference of thereof. At least one set of induction coils opposing to the permanent magnets is supported on the a mounting foot such that the induction coils surround the permanent magnets with a proper gap between them. Accordingly, an induction takes place between the permanent magnets and the induction coils after the flywheel is brought into rotation. Meanwhile, the inducted electric energy may be transmitted by a power cord to necessary electronic devices (like a motor and an electric console) on the exercise apparatus, thereby achieving the self-generating effect.
    Type: Application
    Filed: June 27, 2006
    Publication date: December 27, 2007
    Inventor: Leao Wang
  • Patent number: 7296409
    Abstract: A turbocharger comprises a turbine wheel and a compressor wheel mounted to a turbocharger shaft. An electric induction motor is provided for assisting rotation of the compressor wheel in predetermined circumstances. The motor comprises a fixed stator having motor field coils which generate a rotating magnetic field when energised by an AC control signal which induces eddy current flow in a rotor to generate a rotor magnetic field which in turn interacts with the stator magnetic field producing torque in the rotor.
    Type: Grant
    Filed: January 30, 2004
    Date of Patent: November 20, 2007
    Assignee: Holset Engineering Company, Ltd.
    Inventor: Edward Spooner
  • Patent number: 7294949
    Abstract: A single-phase induction motor comprises a stator having a stator coil; an induction cage rotor rotatably inserted into a receiving groove of the stator, having a rotation shaft at a center thereof, having a plurality of first conductor bars at an outer peripheral portion thereof with the same interval in a circumferential direction, having a protrusion portion at an outer circumferential surface thereof, and having a plurality of second conductor bars installed at the protrusion portion in a circumferential direction; and a permanent magnet rotor free-rotatably installed between the stator and the induction cage rotor.
    Type: Grant
    Filed: October 19, 2005
    Date of Patent: November 13, 2007
    Assignee: LG Electronics Inc.
    Inventors: Seung-Do Han, Hyoun-Jeong Shin, Jae-Hong Ahn
  • Patent number: 7276830
    Abstract: A motor (1) has a stator (2) and a rotor (10) mounted for rotation in the stator. A commutating salient pole (11) of the stator as a winding (7), and a field-producing salient pole (12) has a winding (8). The rotor has at least two salient poles (10a, b). An outer back-iron (13) magnetically joins bases of said stator poles. An inner back-iron (14) extends from the field pole around the rotor to such an extent that a substantial amount of the magnetic field in the rotor between its poles is short-circuited by the inner back-iron, at least for a part of its rotation. An electrical circuit powers the windings to drivingly rotate the rotor.
    Type: Grant
    Filed: June 11, 2002
    Date of Patent: October 2, 2007
    Inventor: Paul Lefley
  • Publication number: 20070188038
    Abstract: A self magnetizing motor is disclosed, which comprises a stator which is comprised of a plurality of sheets including a plurality of stator slots and exciter slots formed at fixed intervals along an outer circumferential surface of the center, a teeth provided between each of the stator slots, and an exciter pole formed between the exciter slots; an exciter coil which is wound on each exciter slot; and a rotor which is rotatably inserted into the center (C) of the stator, and is provided with an exciter magnetizable portion on an outer circumferential surface to be magnetized by the exciter coil; wherein the exciter pole is positioned at the part of the stator to form a back yoke of an increased size. Preferably, the exciter pole is positioned at corner of the stator so that a rear stator portion of the exciter pole is increased in size.
    Type: Application
    Filed: December 8, 2006
    Publication date: August 16, 2007
    Applicant: LG ELECTRONICS INC.
    Inventors: Sung-Ho LEE, Jae-Hak CHOI, Jae-Min KIM
  • Publication number: 20070182263
    Abstract: Disclosed is an induction motor providing a method of increasing a motors revolutions by connecting a plurality of stators and a plurality of rotors in a specific configuration that will result in an increase in RPM's.
    Type: Application
    Filed: January 23, 2007
    Publication date: August 9, 2007
    Inventor: Janai Vargas
  • Publication number: 20070176522
    Abstract: The preferred embodiment the invention proposes pertains to a three-phase induction motor, and operates on the premises of having the extension cords on two ends of the motor embedded with several balancing eccentric washers and a balancing eccentric block added, of which the eccentric block contains a sleeve bearing, and one end of the eccentric block is fitted with a bolt, with the bolt head covered with rubber; o-ring is fitted between the balancing eccentric washer and balancing eccentric block, whereby using the invention's frequency changer for controlling an AC 3-phase induction motor serves to generate multiple frequencies for generating different amplitudes, which can be use to control the speed and load emitted between the eccentric block and balancing eccentric washer.
    Type: Application
    Filed: January 11, 2007
    Publication date: August 2, 2007
    Inventor: Huan-Yau Peng
  • Patent number: 7250701
    Abstract: An end surface of a rotor core is offset from an end surface of a stator core by a predetermined amount in an axial direction going away from Hall ICs. In an operating condition of the motor, magnetomotive forces generating from the stator core induce a thrust force acting on the rotor core. The gap (i.e. distance) between the magnet and the Hall ICs does not exceed a pre-designated appropriate distance, and is stably maintained at a constant level (or range). In other words, the gap (i.e. distance) between the magnet and the Hall ICs can be accurately maintained at the pre-designated appropriate distance by utilizing the magnetic attraction force generating from the stator core.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: July 31, 2007
    Assignee: DENSO CORPORATION
    Inventors: Shigeru Yoshiyama, Taku Itoh, Kiyoshi Kimura
  • Patent number: 7239061
    Abstract: Both the stator core and the rotor core of a switching pattern AC induction motor are fabricated by soft magnetic material laminations or ferrite material, etc., both of which have corresponding frequency characteristic. The rotor is a squirrel cage rotor. Switching pattern excitation is adopted in the stator pole, of which the excitation voltage is sine wave pulse width modulated or sine wave pulse amplitude modulated within the frequency range of voice and ultrasonic. Under the condition of the same power output, the present motor reduces its size and mass to a fraction of or tenth of that of an ordinary one. Meanwhile, it reduces the cost of manufacture. It realizes stepless speed regulating from zero to several thousand rpm while keeping well mechanical characteristic performance.
    Type: Grant
    Filed: January 9, 2003
    Date of Patent: July 3, 2007
    Inventors: Youguo Huang, Wei Huang
  • Patent number: 7230360
    Abstract: A switched reluctance machine (SRM) having a rotor and stator pole numerical relationship of S number of stator poles and R number of rotor poles, where R=2S?2, when S is greater than 4; provides improved power density, torque production, torque ripple, and acoustic noise, and is readily adaptable to existing hardware such as known controllers and the like.
    Type: Grant
    Filed: November 8, 2004
    Date of Patent: June 12, 2007
    Assignee: Illinois Institute of Technology
    Inventors: Piyush C. Desai, Ali Emadi
  • Patent number: 7116030
    Abstract: An electric motor for operation at very high speeds comprises a ferromagnetic stator (11), a ferromagnetic rotor (13) having a rotor core (16) with a plurality of reluctance poles (17) spaced from the stator by an air gap (G), and a rotor shaft (14) supporting the rotor core for rotation in the stator, and a winding (12) on the stator for producing a multipolar magnetic field continuously travelling along the air gap and linking the stator with the reluctance poles of the rotor. At least a part of the outer portion of each reluctance pole (17) of the rotor core (16) forms a saturable surface layer having a saturation flux density which is lower than the flux density in the air gap (G) that saturates the teeth (11A) of the stator (11). The rotor core (16), including the reluctance poles (17), and the rotor shaft (14) are formed from a single solid piece of ferromagnetic material.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: October 3, 2006
    Inventor: Vilmos Torok
  • Patent number: 7116029
    Abstract: There is provided an electric motor having a flat form factor. The electric motor has a rotor with a shaft attached thereto. The rotor further includes a plurality of teeth disposed thereon. The motor further includes a stator having an axial length. A plurality of teeth are disposed on the stator such that a gap is defined between the teeth of the stator and the teeth of the rotor. The motor further includes a plurality of copper windings disposed around each of the teeth of stator. Each of the windings has a length of end copper equal to about twice the axial length of the stator. In this regard, the end of the wire is greater than the width of the stator such that the form factor of the motor can be flattened.
    Type: Grant
    Filed: July 19, 2004
    Date of Patent: October 3, 2006
    Assignee: RT Patent Company, Inc.
    Inventor: Jack H. Kerlin
  • Patent number: 7102259
    Abstract: A rotor of a synchronous induction electric motor according to the present invention includes a slot for generating induction torque and a slit for generating reluctance torque. The slot and the slit are filled up with aluminum which is short-circuited by an end-ring at each of both ends of the rotor, and the slit includes a non-filling part penetrating in the direction of the rotational axis and not filled up with the aluminum.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: September 5, 2006
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hitoshi Kawaguchi, Yoshio Takita, Hayato Yoshino
  • Patent number: 7084599
    Abstract: A motor controller is capable of swiftly driving a motor at the initial stage and driving the motor with high efficiency and low power consumption after swiftly driving the motor at the initial stage by including a first capacitor connected in series with stator coils of the motor and a PTC thermistor (Positive Temperature Coefficient thermistor) connected in parallel with the first capacitor.
    Type: Grant
    Filed: November 23, 2004
    Date of Patent: August 1, 2006
    Assignee: LG Electronics Inc.
    Inventors: Seung-Do Han, Hyoun-Jeong Shin
  • Patent number: 7081732
    Abstract: A motor controller is capable of swiftly driving a motor at the initial stage and driving the motor with high efficiency and low power consumption after swiftly driving the motor at the initial stage by including a first capacitor connected in series with a common terminal to which the main coils and the sub-coils of the motor are connected and a PTC thermistor (Positive Temperature Coefficient thermistor) connected in parallel with the first capacitor.
    Type: Grant
    Filed: November 23, 2004
    Date of Patent: July 25, 2006
    Assignee: LG Electronics Inc.
    Inventors: Seung-Do Han, Hyoun-Jeong Shin
  • Patent number: 7071657
    Abstract: A single-pole type generator with low loss magnetic core is excited by a field coil that is part of a low loss series resonant circuit tuned to a desired AC power frequency, which may be frequencies such as 50 Hz or 60 Hz or 400 Hz. The series resonant circuit is excited at the resonant frequency. The resulting resonant behavior of the excitation circuit automatically provides the high driving voltages and sinusoidal energy storage patterns needed to efficiently modulate the magnetic field at the desired power frequency. This modulation of the excitation field is amplified by mechanical power from a rotating shaft and modulates the output current and voltage of a single phase output circuit of the single-pole type generator at that power frequency in a sinusoidal pattern thus delivering alternating current power without any requirement for further electronic rectification, commutation or processing.
    Type: Grant
    Filed: March 4, 2004
    Date of Patent: July 4, 2006
    Assignee: Raven Technology, LLC
    Inventors: Christopher N. Tupper, Duncan G. Wood
  • Patent number: 7034422
    Abstract: A rotor for an electrical motor may include a plurality of salient radial field rotor poles and a plurality of salient axial field rotor poles. The radial field rotor poles and the axial field rotor poles are respectively oriented on the rotor to receive or convey substantially perpendicular flux fields. Additionally, the radial field rotor poles may include both inner and outer peripheral rotor poles for communicating radial flux fields with separate coaxial stators.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: April 25, 2006
    Assignee: Virginia Tech Intellectual Properties, Inc.
    Inventor: Krishnan Ramu
  • Patent number: 7030531
    Abstract: An electric motor operated by AC current, that includes a stator and a rotor supported for rotation about an axis relative to the stator. The stator is provided with field windings angularly distributed about the rotor axis and capable of producing a magnetic field vector in the space of the rotor. Circuitry delivers AC current to the windings in a manner that produces an AC magnetic field vector that moves around the axis of the rotor. The rotor has a construction, such as an axially extending conductive loop, that changes its reluctance in the AC magnetic field depending on its orientation to the AC magnetic field vector whereby the rotor is caused to rotate in synchronization with the movement of the AC magnetic field vector.
    Type: Grant
    Filed: May 3, 2005
    Date of Patent: April 18, 2006
    Inventor: Lambert Haner
  • Patent number: 7015615
    Abstract: A TPSRM may include a stator, having a plurality of poles and a ferromagnetic or iron back material, and a rotor having a plurality of poles and a ferromagnetic or iron back material. A current flowing through coils wound around a first set of the plurality of stator poles induces a flux flow through the first set of stator poles and portions of the stator back material during a first excitation phase. A current flowing through coils wound around a second set of the plurality of stator poles induces a flux flow through the second set of stator poles and portions of the stator back material during a second excitation phase. The numbers of stator and rotor poles for this TPSRM are selected such that substantially no flux reversal occurs in any part of the stator back material as a result of transitioning between the first and second excitation phases.
    Type: Grant
    Filed: March 17, 2004
    Date of Patent: March 21, 2006
    Assignee: Virginia Tech Intellectual Properties, Inc.
    Inventors: Krishnan Ramu, Nimal Savio Lobo
  • Patent number: 7012350
    Abstract: A switched reluctance machine includes a stator with a plurality of circumferentially-spaced stator segment assemblies that include salient stator poles and inter-polar stator slots. Each of the stator segment assemblies includes a stack of stator plates forming a stator segment core, an end cap assembly, and winding wire wound around the stator segment core and the end cap assembly. The rotor defines a plurality of rotor poles. The rotor tends to rotate relative to the stator to maximize the inductance of an energized winding. A drive circuit energizes the winding wire around the stator segment assemblies based on a rotational position of the rotor. Each stator plate includes a first radially outer rim section and a tooth section that extends radially inwardly from a first center portion of the first radially outer rim section.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: March 14, 2006
    Assignee: Emerson Electric Co.
    Inventors: C. Theodore Peachee, Donald J. Williams, James A. Wafer, Marielle Piron, Steven P. Randall, Richard S. Wallace, Jr., Michael L. McClelland
  • Patent number: 6921997
    Abstract: The present invention provides an active magnetic bearing (AMB) with improved configuration. The active magnetic bearing includes a stator which possesses only three magnetic poles. The three magnetic poles are arranged radially with an equiangular degree along an internal circumference of the stator and not in the same semicircle. Each of the magnetic poles is equipped with an individual power amplifier for providing coil current. In the other way, two of the magnetic poles can be equipped with only one power amplifier, and the other magnetic pole is equipped with an individual power amplifier so as to reduce the number of the power amplifiers.
    Type: Grant
    Filed: December 23, 2002
    Date of Patent: July 26, 2005
    Assignee: National Chung Cheng University
    Inventors: Shyh-Leh Chen, Chan-Tang Hsu
  • Patent number: 6903477
    Abstract: An electric machine selectively operates as a generator mode or a motor mode. The electric machine includes a stator core, a multi-phase armature winding, a field coil, a moving core having a plurality of salient poles so as to move relative to the stator core to cross the magnetic field. Field current is supplied to the field coil differently according to operation mode. A portion of the armature winding is short-circuited to form an additional magnetic field that has a phase different from the magnetic field of the field coil. Therefore, the rotary core moves relative to the stator core when the operation mode is in the motor mode.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: June 7, 2005
    Assignee: Denso Corporation
    Inventors: Shin Kusase, Tsutomu Shiga
  • Patent number: 6897591
    Abstract: A sensorless switched reluctance machine includes a stator with a plurality of circumferentially-spaced stator segment assemblies that include salient stator poles and inter-polar stator slots. Each of the stator segment assemblies includes a stack of stator plates forming a stator segment core, an end cap assembly, and winding wire wound around the stator segment core and the end cap assembly. The rotor defines a plurality of rotor poles. The rotor tends to rotate relative to the stator to a rotational position that maximizes the inductance of an energized winding. A sensorless drive circuit derives rotor position and energizes the winding wire around the stator segment assemblies based on the derived rotor position. Each stator plate includes a first radially outer rim section and a tooth section that extends radially inwardly from a first center portion of the first radially outer rim section.
    Type: Grant
    Filed: March 26, 2001
    Date of Patent: May 24, 2005
    Assignee: Emerson Electric Co.
    Inventors: C. Theodore Peachee, Donald J. Williams, James A. Wafer, Marielle Piron, Steven P. Randall, Richard S. Wallace, Jr., Michael L. McClelland
  • Patent number: 6888279
    Abstract: An electric motor operated by AC current, that includes a stator and a rotor supported for rotation about an axis relative to the stator. The stator is provided with field windings angularly distributed about the rotor axis and capable of producing a magnetic field vector in the space of the rotor. Circuitry delivers AC current to the windings in a manner that produces an AC magnetic field vector that moves around the axis of the rotor. The rotor has a construction, such as an axially extending conductive loop, that changes its reluctance in the AC magnetic field depending on its orientation to the AC magnetic field vector whereby the rotor is caused to rotate in synchronization with the movement of the AC magnetic field vector.
    Type: Grant
    Filed: October 22, 2003
    Date of Patent: May 3, 2005
    Inventor: Lambert Haner
  • Patent number: 6876122
    Abstract: The present invention is directed to an electric motor for rotating an object around a central axis. The electric motor includes a motor casing. A circular segmented rail element is disposed within the motor casing about the central axis. The circular segmented rail element includes metallic non-ferrous segments interleaved with non-metallic segments. Each of the metallic non-ferrous segments has a predetermined segment length. At least one coil element is connected to the motor casing. The circular segmented rail element is disposed adjacent the at least one coil element. The at least one coil element has a predetermined coil length that is less than or equal to the predetermined segment length. The at least one coil element is configured to apply electromagnetic energy to the circular segmented rail element, such that the circular segmented rail element rotates around the central axis.
    Type: Grant
    Filed: September 16, 2002
    Date of Patent: April 5, 2005
    Assignee: Lockheed Martin Corporation
    Inventor: Brad C. Hansen
  • Patent number: 6870295
    Abstract: An oscillating motor is provided which can be reciprocally rotated within a predetermined rotation region without any conversion device for changing to a linear movement, and which can be simply connected to an existing apparatus. The oscillating motor includes a set of teeth formed on the stator which are configured to engage with a corresponding set of teeth formed on the rotor when the motor is in operation. Alternately formed concave and convex regions on the teeth increase a contact area between the rotor and stator, thus increasing torque and operating efficiency of the motor without increasing size.
    Type: Grant
    Filed: October 29, 2001
    Date of Patent: March 22, 2005
    Assignee: LG Electronics Inc.
    Inventors: Jun Young Lim, Yun Chul Jung
  • Patent number: 6867522
    Abstract: A synchronous machine (10), in particular, for a starter-generator of an internal combustion engine, includes a stator, a rotor (22) having a rotor shaft (24), a stack of sheets (28), and squirrel cage (30) non-rotatably connected with the rotor shaft (24) and the stack of sheets (28). The squirrel cage (30) has a short circuit ring (36) on its opposite front ends, which is secured to an annular reinforcement element (40, 42). The reinforcement elements (40, 42) do not overlap adjacent, outer circumferential surfaces of the squirrel cage (32) or the short circuit rings (36).
    Type: Grant
    Filed: June 20, 2003
    Date of Patent: March 15, 2005
    Assignee: Robert Bosch GmbH
    Inventors: Johannes Vlemmings, Karl-Juergen Roth
  • Patent number: 6849983
    Abstract: The rotary machine is composed of the rotor having magnetic poles and the stator having the stator yoke portion constituting the iron core tooth portion wound by the stator winding and the flux flow path of the magnetic poles. The rotor is composed of a metallic material having ferromagnetic parts and non-magnetic parts as a member and has a magnetic barrier area composed of the slit portion for blocking the bypath magnetic path in the periphery of the rotor and the non-magnetic parts. The rotary machine that produced torque can be increased sufficiently and the mechanical strength during high-speed running is improved and an electrical vehicle using it.
    Type: Grant
    Filed: March 2, 2001
    Date of Patent: February 1, 2005
    Assignees: Hitachi, Ltd., Hitachi Metals, Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Masashi Kitamura, Kiyoshi Yamaguchi, Osamu Koizumi, Suetaro Shibukawa, Shigeki Morinaga, Yukinori Taneda, Hideki Nakamura, Hakaru Sasaki, Shinichiro Yokoyama
  • Publication number: 20040263013
    Abstract: A TPSRM may include a stator, having a plurality of poles and a ferromagnetic or iron back material, and a rotor having a plurality of poles and a ferromagnetic or iron back material. A current flowing through coils wound around a first set of the plurality of stator poles induces a flux flow through the first set of stator poles and portions of the stator back material during a first excitation phase. A current flowing through coils wound around a second set of the plurality of stator poles induces a flux flow through the second set of stator poles and portions of the stator back material during a second excitation phase. The numbers of stator and rotor poles for this TPSRM are selected such that substantially no flux reversal occurs in any part of the stator back material as a result of transitioning between the first and second excitation phases.
    Type: Application
    Filed: March 17, 2004
    Publication date: December 30, 2004
    Inventors: Krishnan Ramu, Nimal Savio Lobo