Magnetic Shunts For Shifting Field Flux Patents (Class 310/190)
  • Patent number: 6504281
    Abstract: A fault tolerant synchronous machine has a stator with a core containing a plurality of phase windings, a rotor supported for rotation within the core, and a non-magnetic sleeve affixed to the stator and disposed in the space between the stator and the rotor and having a plurality of slots extending parallel to the axis of the rotor and positioned to receive high permeability inserts for shunting the flux paths of faulty stator windings to permit low power operation of a synchronous machine having faulty stator windings.
    Type: Grant
    Filed: July 12, 2000
    Date of Patent: January 7, 2003
    Assignee: Electric Boat Corporation
    Inventors: James Stanley Smith, Gregory John Kudrick, Abdul Rehman Bilal
  • Publication number: 20020195898
    Abstract: A magnetic device having a stator assembly having a magnetic flux return path comprising at least a pair of pole plates located a fixed distance apart from each other and at least one flux return strip pressed between each pair of spaced apart pole plates, and a rotor assembly having permanent magnetic material and being disposed for rotation relative to the stator assembly. Use of the flux return strip eliminates the need for a housing of ferrous material to complete the flux return path and facilitates flexible design of light-weight non-metallic housings and mounting systems or integral mounting to mating components.
    Type: Application
    Filed: September 6, 2002
    Publication date: December 26, 2002
    Inventors: David J. Ineson, William Loxsom, Alois Christiaens
  • Patent number: 6492753
    Abstract: A brushless permanent magnet electric motor with a fixed radial air gap is operated to a much higher speed than normal maximum speed by the reduction in effective magnet pole strength. Increasing the amount of axial misalignment of the permanent magnet rotor and stator proportionally increases the speed and reduces the torque. The permanent magnet rotor is offset axially to provide axial misalignment between the rotor magnet poles and the stator, reducing the effective magnet pole strength or flux to the stator. An integral constant velocity linear bearing is used to couple the movable rotor and the fixed position motor shaft. A thrust bearing is actuated to offset the magnetic rotor against the attractive magnetic forces toward the stator. The use of a constant velocity linear bearing allows the motor shaft, radial support bearings, position encoder, cooling fan, and output coupling to remain in a constant position while rotor position is offset.
    Type: Grant
    Filed: March 8, 2002
    Date of Patent: December 10, 2002
    Assignee: Dura-Trac Motors, Inc.
    Inventors: Lawrence P. Zepp, Jerry W. Medlin
  • Patent number: 6455973
    Abstract: A magnetic device having a stator assembly having a magnetic flux return path comprising at least a pair of pole plates located a fixed distance apart from each other and at least one flux return strip pressed between each pair of spaced apart pole plates, and a rotor assembly having permanent magnetic material and being disposed for rotation relative to the stator assembly. Use of the flux return strip eliminates the need for a housing of ferrous material to complete the flux return path and facilitates flexible design of light-weight non-metallic housings and mounting systems or integral mounting to mating components.
    Type: Grant
    Filed: January 29, 1999
    Date of Patent: September 24, 2002
    Assignee: Siemens VDO Automotive Corp.
    Inventors: David J. Ineson, William Loxsom, Alois Christiaens
  • Publication number: 20020121828
    Abstract: An electromagnetic adjusting device for automatic transmissions of motor vehicles has an electromagnet having a magnetic coil, a substantially cup-shaped housing which surrounds the magnetic coil and is composed of a ferromagnetic material, the housing having a housing bottom, a ferromagnetic central part which extends from the housing bottom and supports the magnetic coil, and a movable armature located before the central part and leaving a working air gap so as to form with the housing and the central part a magnetic circuit which has a magnetic resistance for a magnetic flux, and means for changing the magnetic resistance, the means for changing the magnetic resistance including an axial depression provided in the central part and an axially displaceable ferromagnetic filling member inserted in the depression and limiting with a bottom of the depression an auxiliary air gap.
    Type: Application
    Filed: January 17, 2002
    Publication date: September 5, 2002
    Inventors: Christiane Ketschau, Markus Deeg, Lothar Pfeiffer
  • Publication number: 20020047448
    Abstract: A motor-generator is disclosed, in which electromagnet coils are arranged at axially opposite ends of the stator, each to each end, while connections among winding sets are changed in response to the rpm of the rotor. This makes it possible to control the voltage, either at high speed or at low speed, thereby increasing the torque at low speed, or the torque on the rotor shaft at low speed and rendering the voltage stable. A rotor is comprised of a cylindrical magnetic path axially elongating to extent confronting the electromagnet coils, and a permanent-magnet member of more than one permanent-magnet piece extending axially over the magnetic path.
    Type: Application
    Filed: August 7, 2001
    Publication date: April 25, 2002
    Inventor: Hideo Kawamura
  • Patent number: 6255753
    Abstract: An electro magnetic rotating machine comprising at least a rotor having at least one magnet creating rotor magnetic poles; and at least one pair of axially spaced apart solenoids disposed on opposite sides of the rotor magnetic poles, the axis of each solenoid is arranged to be transverse a radius of the path of rotation of the rotor. The solenoids are configured to minimize overlapping of magnetic flux between at least one of the rotor magnetic poles and one of the solenoids when said magnetic pole is adjacent to said solenoid.
    Type: Grant
    Filed: November 12, 1999
    Date of Patent: July 3, 2001
    Inventor: William Barry MacDonald
  • Patent number: 6242840
    Abstract: A flux collector for an electrical machine includes a continuous strand of ferromagnetic material; and an electrical insulator covering the strand. The strand forms a tight cylindrical coil including a plurality of turns that are stacked axially. The insulator provides turn-to-turn insulation. The insulated wire is covered with a binder and cured. The strand can be a high permeability wire made of soft iron, silicon steel or cobalt steel. In the alternative, the strand can be a strip of METGLAS® amorphous alloy.
    Type: Grant
    Filed: June 7, 1999
    Date of Patent: June 5, 2001
    Assignee: AlliedSignal Inc.
    Inventors: Joseph Denk, Carol Oximberg
  • Patent number: 6229244
    Abstract: A synchronous machine formed as a generator for a motor vehicle has a stator, a rotor, an excitation system composed of a plurality of electrically excited individual poles provided in the stator and the rotor and formed as claw poles excited by a joint excitation coil, and a stray field compensation device arranged in free spaces between the claw poles, the stray field compensation device being formed as an additional winding through which current flows and which surrounds the claw poles so that an axial current direction changes from one free space to another free space and a current to neighboring claw poles produces an additional flux which supports a main flux and counteracts a stray flux.
    Type: Grant
    Filed: February 4, 1999
    Date of Patent: May 8, 2001
    Assignee: Robert Bosch GmbH
    Inventor: Istvan Ragaly
  • Patent number: 6166463
    Abstract: The present invention resides in a radial air gap machine with a serrated air gap that can minimize external axial forces. This is accomplished by controlling the relationship between the air gap surfaces in the stator and rotor sections. To control the relationship between the stator sections and the rotor section in a vertical motor a bushing with external and internal thread of opposite hand with the internal thread having a steeper helix angle is twisted into a bearing mount and over a motor shaft. Thus, a vertical hollow shaft motor with magnetic balance thrust is adjusted.In axial air gap machines, the magnetic force produced in the air gaps can also be utilized to compensate for axial loads.
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: December 26, 2000
    Inventor: Richard C. Woodward, Jr.
  • Patent number: 6118201
    Abstract: A brushless resolver comprising a housing, a rotor rotatably mounted in the housing, a rotary transformer comprising a primary winding carried by the housing and secondary winding on the rotor and operatively associated with the primary winding, a resolver comprising a stator winding carried by the housing and a rotor winding on the rotor and operatively associated with the stator winding, characterized by an electromagnetic flux absorber in the housing between the rotary transformer and the resolver for absorbing leakage electromagnetic flux from the rotary transformer so as to reduce any deviation between the indicated electrical position of the rotor and the actual mechanical position of the rotor during each revolution of the rotor. The flux absorber comprises a copper ring between the rotary transformer primary winding and the resolver stator winding so that the leakage flux creates eddy currents in the ring thereby absorbing or reducing the leakage flux.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: September 12, 2000
    Assignee: American Precision Industries Inc.
    Inventors: Patrick J. Dulin, David E. Hawes, Ray K. Trumbauer
  • Patent number: 6097129
    Abstract: An electronically commutated external rotor motor has an external rotor having a cup-shaped housing and a radially magnetized permanent magnet connected in the cup-shaped housing. An interior stator is positioned in the cup-shaped housing. The interior stator has a laminated core having grooves. Windings are provided within the grooves. The windings have first end turns proximal to a bottom of the cup-shaped housing and second end turns positioned distal to the bottom. The first and second end turns electrically connect the windings to one another. The permanent magnet has an end face remote from the bottom of the cup-shaped housing. At least one galvano-magnetic rotor position sensor is arranged opposite the end face of the permanent magnet so as to be located within a magnetic leakage of the permanent magnet and within a magnetic leakage of the interior stator. The at least one rotor position sensor is designed to control current within at least a portion of the windings.
    Type: Grant
    Filed: March 19, 1999
    Date of Patent: August 1, 2000
    Assignee: Papst-Motoren GmbH & Co. KG
    Inventors: Patrick Furtwangler, Hermann Rappenecker, Harald Reich, Gabor Szondi
  • Patent number: 6013965
    Abstract: This invention is to provide a low-cost structure that a cogging torque and a torque ripple are small and a stable rotation is provided in a radial gap type motor.A portion that stator pole teeth 37 to become interpoles are provided between stator poles 38 and a plurality of stator pole teeth 37 are not continuously provided between the partial stator poles 38 is provided. As a result, in this invention, a magnetic attraction force between the stator pole teeth 38 and the rotating pole 9 of a rotor 6 is stronger in the case that the pole teeth 37 are provided than in the case that the pole teeth 37 are not provided.Accordingly, the rotational shaft 12 of the rotor 6 is supported at three points of points P, Q and R of the bearing cylinder 4, and a rotary force is received at the point P as a center. As a consequence, the rotational shaft 12 is rotated with less contact friction with the bearing cylinder 4.
    Type: Grant
    Filed: July 5, 1996
    Date of Patent: January 11, 2000
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani
  • Patent number: 5969457
    Abstract: A flywheel energy conversion device provides highly efficient conversion between kinetic and electrical energy. The flywheel produces increased output by providing armature coils in an air gap formed about the flywheel (both radial and axial embodiments are described). In preferred embodiments, field coils of a magnetic circuit are energized with DC drive current that creates homopolar flux within a rotating solid rotor having teeth cut from a flat disk. The total reluctance of the magnetic circuit and total flux remain substantially constant as the rotor rotates. The flux may travel radially outward and exit the flat disk through the teeth passing across an armature air gap. Airgap armature coils are preferably utilized in which the changing flux density (due to the rotating teeth) induces an output voltage in the coils.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: October 19, 1999
    Assignee: Active Power, Inc.
    Inventors: David B. Clifton, Joseph F. Pinkerton
  • Patent number: 5942829
    Abstract: An electrical machine includes both a permanent magnet source of field excitation and an electromagnetic source of field excitation. The electrical machine also includes a homopolar rotor, which carries the permanent magnet source, and a lamination stack having a middle portion and outer portions. The homopolar rotor and the middle portion of the lamination stack conduct flux generated by the permanent magnet source. The homopolar rotor and the outer portions of the lamination stack conduct flux generated by the electromagnetic source when the electromagnetic source is energized.
    Type: Grant
    Filed: August 13, 1997
    Date of Patent: August 24, 1999
    Assignee: AlliedSignal Inc.
    Inventor: Co Si Huynh
  • Patent number: 5907202
    Abstract: A thermo-sensitive actuator capable of operating without the need of providing a temperature detector as a separate member. The actuator includes a stator made of a magnetic material to form a yoke. A rotor is rotatably provided in an opening provided in the stator. The actuator further includes pole pieces for magnetically connecting the stator and the rotor. A magnetic source is provided in any of the magnetic paths formed by the constituent elements. A thermo-sensitive magnetic material, which shows a change in magnetic characteristics, e.g. permeability, saturated magnetic flux density, or residual magnetic flux density, according to temperature, is provided in a part of the magnetic paths.
    Type: Grant
    Filed: November 13, 1997
    Date of Patent: May 25, 1999
    Assignee: Mikuni Corporation
    Inventor: Tetsuo Muraji
  • Patent number: 5825113
    Abstract: A permanent magnet machine combines both principles of variable reluctance machines and permanent magnets, and comprises a rotor with salient rotor poles and a stator with salient stator poles. A pair of ferrite arched permanent magnets are embedded in the stator yoke beneath respective stator poles and are arranged symmetrically around the central axis of the machine. A field winding for boosting or weakening the primary flux generated by the permanent magnets is wound in a special arrangement.
    Type: Grant
    Filed: July 5, 1995
    Date of Patent: October 20, 1998
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Thomas A. Lipo, Yue Li
  • Patent number: 5767601
    Abstract: A permanent magnet electric generator has a raised output as compared with the output of a similar conventional permanent magnet generator in which the polar arcuate angle of the permanent magnets is equal to the polar arcuate angle of controlling magnetic poles. Electricity is generated in armature coils 16 by the rotation of permanent magnets 8 of a rotor 4. Controlling magnetic poles 9 formed of a magnetic material are interposed between the permanent magnets 8 of the rotor 4, and a field controlling coil 17 is provided on a stator 11. The value of the polar arcuate angle .theta. m of the permanent magnets 8 divided by the sum of the polar arcuate angle .theta. m of the permanent magnets 8 plus the polar arcuate angle .theta. p of the controlling magnetic poles 9 is set at 0.55 to 0.7.
    Type: Grant
    Filed: December 13, 1996
    Date of Patent: June 16, 1998
    Assignee: Mitsuba Corporation
    Inventor: Hidekazu Uchiyama
  • Patent number: 5751075
    Abstract: A linear motor magnet assembly which is capable of facilitating the assemblage and enhancing the reliability thereof by attaching magnets on a cylindrical magnet shell to form a magnet assembly, and which includes the cylindrical magnet shell, and a plurality of magnets attached on a peripheral surface of the magnet shell.
    Type: Grant
    Filed: November 5, 1996
    Date of Patent: May 12, 1998
    Assignee: L.G. Electronics Inc.
    Inventors: Byoung Ha Kwon, Hyeong Kook Lee
  • Patent number: 5742106
    Abstract: A thermo-sensitive actuator capable of operating without the need of providing a temperature detector as a separate member. The actuator includes a stator made of a magnetic material to form a yoke. A rotor is rotatably provided in an opening provided in the stator. The actuator further includes pole pieces for magnetically connecting the stator and the rotor. A magnetic source is provided in any of the magnetic paths formed by the constituent elements. A thermo-sensitive magnetic material, which shows a change in magnetic characteristics, e.g. permeability, saturated magnetic flux density, or residual magnetic flux density, according to temperature, is provided in a part of the magnetic paths.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: April 21, 1998
    Assignee: Mikuni Corporation
    Inventor: Tetsuo Muraji
  • Patent number: 5650680
    Abstract: A permanent magnet generator includes an annular stator with windings on the inner face. A round rotor is rotatably mounted in the stator, and includes a plurality of circumferentially spaced rectangular openings inwardly of the outer peripheral portion of the core. Radial U-shaped grooves are formed between the openings. A magnetic unit, including a rectangular permanent magnet and an abutting magnetic conductive shim, is close-fitted within each opening. The core includes core lamination and separate end laminations of a structure corresponding to the core laminations. The end laminations are rotated about an axis through the core to offset the magnetic unit openings with respect to the magnetic unit opening of the core laminations. The laminations are riveted together, with the offset end lamination retaining the magnetic units within the core.
    Type: Grant
    Filed: December 11, 1995
    Date of Patent: July 22, 1997
    Assignee: Marathon Electric Mfg. Co.
    Inventor: Stanley S. Chula
  • Patent number: 5631505
    Abstract: A moving coil linear actuator including an elongated permanent magnet having a cross-sectional width substantially greater than its edge height and having an elongated length of soft magnetic material disposed along one or both edges of the permanent magnet to enhance the magnetic field strength in the gap through which the moving coil translates.
    Type: Grant
    Filed: April 13, 1995
    Date of Patent: May 20, 1997
    Assignee: Eastman Kodak Company
    Inventors: Thomas M. Stephany, William Mey, Edward P. Furlani
  • Patent number: 5606247
    Abstract: A mechanical gear drive system capable of generating electric power comprises a plurality of gears having a plurality of teeth separated by a tooth gap, a U-shaped core having two legs separated by at least one tooth gap, and a yoke. This core is positioned in close proximity to the teeth of the gear. A coil is wound on the yoke, and a converter selectively couples and decouples this coil from a dc power source. The converter has at least a first and a second switch and at least a first and a second diode for cross-coupling the coil to the source to allow current flow back when the switches are disabled. The converter enables the switches prior to alignment of the teeth of the gear with the legs of the core. This couples the coil to the source of dc power and allows dc current to flow from the source through the switches and the coil. When the converter disables the switches after alignment of the teeth with the legs, the coil is decoupled from said source.
    Type: Grant
    Filed: May 5, 1995
    Date of Patent: February 25, 1997
    Assignee: Sundstrand Corporation
    Inventor: Thomas A. Sutrina
  • Patent number: 5600189
    Abstract: An electromagnetic actuator (1) comprises two actuator sections which are translatable relative to one another along an actuator axis (1a) and which are rotatable about the actuator axis, a first actuator section (1) comprising a coil system and a second actuator section (3) comprising a permanent magnet system for cooperation with the coil system via an air gap. The coil system is arranged on a magnetically conductive yoke (5) and comprises a cylindrical translation coil (9) and a toroidal rotation coil (7), which are coaxial with the actuator axis. The permanent magnet system comprises an annular magnet (11), which is coaxial with the actuator axis, for cooperation with both the translation coil and the rotation coil. The magnet has a radial magnetisation (B) which is interrupted by an annular segment (13). The magnetically conductive yoke has a central core (5b) around which the translation coil is arranged and a shell (5a) on which the rotation coil is disposed.
    Type: Grant
    Filed: July 6, 1995
    Date of Patent: February 4, 1997
    Assignee: U.S. Philips Corporation
    Inventors: Johannes M. A. M. Van Geel, Johan C. Compter, Volker Kessler
  • Patent number: 5444321
    Abstract: Object of the present invention is to provide an induction alternating current generator on vehicle and a method for generating alternating current in a generator on vehicle, which improve the efficiency of the generator by increasing magnetic flux permeating a stator core.Second electromagnetic exciting means for generating magnetic field in the direction of repelling the leak magnetic flux between neighboring claw poles, are provided in the spaces formed by the neighboring claw poles engaging each other at a gap and first electromagnetic exciting means provided inside a pair of the rotor cores of the induction alternating current generator on vehicle.
    Type: Grant
    Filed: September 1, 1993
    Date of Patent: August 22, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Yoshiaki Honda, Hitoshi Minorikawa, Hideaki Kamohara
  • Patent number: 5340287
    Abstract: A scroll-type compressor has a crankshaft connected to the rotor of an electric motor for causing an orbiting motion of an orbiting scroll member and having a main shaft formed at one end thereof and supported by a main bearing, an orbiting drive shaft formed on the side of an orbiting end plate opposite to an orbiting scroll wrap and received in an eccentric bearing disposed at an eccentricity in the main shaft, a rolling type upper bearing supporting the end of the crankshaft opposite to the main shaft, and a lift limiting plate fixed to the lower surface of the upper bearing to prevent excessive lift of the crankshaft. A step is formed on the crankshaft between a portion of a greater diameter at which the crankshaft is connected to the rotor, and a portion of a smaller diameter at which the crankshaft is received in the upper bearing.
    Type: Grant
    Filed: September 3, 1991
    Date of Patent: August 23, 1994
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Sadao Kawahara, Yoshinori Kojima, Osamu Aiba
  • Patent number: 5298822
    Abstract: A stepper motor of the permanent-magnet sheet-metal type is constructed of a number of modules, simplifying assembly. The modular parts include a stator having integrally-molded winding bobbins and pole pieces. A rotor mounted in the stator includes a barrier member which separates a plastic, threaded hub molded interiorly from a permanent magnet molded exteriorly. A shaft having a first threaded end rotatably engaged with the interior of the rotor hub has a rectangular central portion extending through a rectangular opening of the stator to convert rotary motion of the rotor to linear motion of the shaft. An opposite end of the shaft includes a molded head and a tubular shield extending from the head. This shield and a tubular portion of the stator molding define a labyrinthal passage which inhibits the passage of contaminants into the rotor. A housing of the motor and a rotatably attached flange include engagable portions to lock the flange at a desired angular position.
    Type: Grant
    Filed: September 10, 1992
    Date of Patent: March 29, 1994
    Assignee: North American Philips Corporation
    Inventors: Edward T. Bosman, Karla C. Pratt, Philip G. Atiyeh, John F. Rutledge
  • Patent number: 5287032
    Abstract: An electric motor has a tubular housing part, permanent magnets arranged inside the housing part, a rotatable motor armature with a collector having a running surface, a plurality of sliding brushes having sliding surfaces abutting against the running surface of the collector, and an element for loading the motor armature in direction of its rotary axis toward the sliding brushes so that the running surface of the collector which in its projection is formed as an annular surface abuts against the sliding surfaces of the sliding brushes.
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: February 15, 1994
    Assignee: Robert Bosch GmbH
    Inventor: Ernst Zolda
  • Patent number: 5200660
    Abstract: An electric machine includes an armature which has a permanent-magnetic excitation part of the machine and a stator which has an induction part of the machine. The induction part includes a first and a second region, each region equipped with current conductors. The armature and the stator are movable relative to each other. The machine includes an electronic commutator which has electronic components. An adjustment to purposefully change a voltage induced in the induction part during operation of the machine, by adjustment of the relative phase of the voltages induced in the two regions of the induction part is achievable due to the first region of the induction part being physically adjustable relative to the second region of the induction part in the direction of relative movement of the armature and the stator. In addition, a sensor is provided in the second region for detecting the instantaneous relative position of the armature and the stator.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: April 6, 1993
    Inventors: Gotz Heidelberg, Andreas Grundl, Peter Ehrhart
  • Patent number: 5185546
    Abstract: An electromagnetic rotation control element, for an idle rotation control device for internal combustion engines, include a magnet housing with at least two magnetic poles and with a rotating armature with an even number of pole pieces that cooperate with magnetic poles, and with a restoring spring that acts on the rotating armature. For the purpose of increasing the influencing possibilities for achieving the required characterizing line of the rotation control device, each pole piece is divided into two pole piece sections, located next to each other in the axial direction and having differently formed contour lines. The one contour line has the shape of an arc of a circle, while the other contour line increasingly deviates from the one pole piece end to the other from this arc of a circle shape.
    Type: Grant
    Filed: September 16, 1991
    Date of Patent: February 9, 1993
    Assignee: Robert Bosch GmbH
    Inventors: Eugen Kielbas, Erhard Renninger
  • Patent number: 5155404
    Abstract: A squirrel-cage induction motor for frequency converter operation includes a rotor which has a rotor core with a plurality of substantially axially extending rotor slots in which rotor conductors are arranged, each rotor slot having a main portion in which a rotor conductor is arranged and a slot opening arranged between the main portion and that surface of the rotor facing the air gap of the motor, and a magnetic bridge arranged to separate the slot opening from the main portion of the slot, wherein the ends of the magnetic bridge adjoin the rest of the rotor core on either side of the slot opening, and the portion of the bridge opposite to the ends extends into the main portion of the slot.
    Type: Grant
    Filed: April 12, 1991
    Date of Patent: October 13, 1992
    Assignee: Asea Brown Boveri
    Inventor: Chandur Sadarangani
  • Patent number: 5089737
    Abstract: A novel DC rotary electric machine of permanent magnet field type is disclosed, in which a plurality of permanent field magnets having an auxiliary pole of magnetic material are arranged alternately with a plurality of field magnets including only a magnetic material along the peripheral direction. The field magnets with the auxiliary poles are arranged adjacently with the field magnets of magnetic material with through bolts extending therebetween.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: February 18, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Toshimi Abukawa, Kazuo Tahara, Noriyoshi Takahashi, Toshio Tomite
  • Patent number: 5068561
    Abstract: A homopolar rotary dynamoelectrical machine used as motor or generator has a dense magnetic flux area and sparse magnetic flux area in the air gap between the confonting pole of the main field yoke, the sparse area being in a by-pass yoke which is positioned closely adjacent the side face of the confronting pole. Thus magnetic flux affecting the conductive member becomes diluted in the area of the by-pass yoke, and in the area where the by-pass yoke is not positioned, the magnetic flux affecting the conductive member is kept as it was. Accordingly, generation due to the difference in the amount of magnetic flux is possible.
    Type: Grant
    Filed: January 17, 1990
    Date of Patent: November 26, 1991
    Inventor: Woo S. Lee
  • Patent number: 5053667
    Abstract: The stator of this flat magnetized-rotor motor comprises sets of pole pieces, arranged substantially radially, the sets being surrounded by corresponding electrical control coils. Separate yoke portions, having surface portions of axially symmetric design, are arranged in contact with the pole pieces of a corresponding set. The flat portions each consist of two sheet elements, forming between them an angle; the portions are inserted radially in the respective slots of a support portion of a stator element. With this arrangement it is possible to produce high-performance motors, at very low cost and whose dimensions in the radial direction are extremely small.
    Type: Grant
    Filed: February 9, 1990
    Date of Patent: October 1, 1991
    Assignee: Portescap
    Inventor: Claude Oudet
  • Patent number: 4934472
    Abstract: A power assisted steering system which utilizes a brushless electric motor having a rotor and a wound stator. The rotor is directly connected to the steering shaft 12 rotated by a driver of the vehicle, and is formed by a number of permanent magnets secured in respective recesses on the steering shaft. The controller 17 associated with the steering system is arranged to switch off the motor 15 above a pre-determined vehicle speed.
    Type: Grant
    Filed: April 11, 1989
    Date of Patent: June 19, 1990
    Assignee: Austin Rover Group Limited
    Inventors: Paul C. Bloor, Jonathan A. Fuller
  • Patent number: 4924123
    Abstract: A linear generator according to the present invention is adapted to generate a voltage proportional to the speed of a movable member or rotor and enable the movable member to be smoothly moved. The linear generator includes a first part having permanent magnets fixed to a yoke which are magnetized to the direction perpendicular to the longitudinal direction of a shaft, and a second part having a coil wound around the bobbins and a housing enclosing the coil. A plurality of magnetic poles are provided between the magnets and coils.
    Type: Grant
    Filed: December 16, 1988
    Date of Patent: May 8, 1990
    Assignees: Aisin Seiki Kabushiki Kaisha, Kabushiki Kaisha Toyota Chuo Kenkyusho
    Inventors: Takanori Hamajima, Yukio Inaguma
  • Patent number: 4900963
    Abstract: A D.C. motor is provided with a higher sustaining torque by providing an ascially extending slot on each tooth of an armature core. The slot is located in the center of the outer surface of each tooth opposite the field magnets.
    Type: Grant
    Filed: September 30, 1988
    Date of Patent: February 13, 1990
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventors: Hiroyuki Amano, Tomoaki Nishimura, Toshinori Sasaki
  • Patent number: 4899074
    Abstract: A rotary dynamo electric machine comprising a stator, a rotor rotatable relative to the stator and having an air gap between the rotor and the stator. The permanent magnet poles of the machine each include a two part flux shunt formed from a material of high saturation flux density, each first portion extending from the back iron, towards the air gap of the machine and being magnetically continuous with the back iron, each first portion being adjacent that end of its respective permanent magnet which is the strong tip end in use. Each shunt second portion extending from the respective shunt first portion circumferentially of the machine towards that end of the respective permanent magnet which is the weak tip end in use, and engaging the air gap face of the respective permanent magnet each second portion in that region thereof which is engaged with the respective permanent magnet being shaped such that its cross-sectional area increases substantially linearly from a minimum at its free end.
    Type: Grant
    Filed: October 11, 1988
    Date of Patent: February 6, 1990
    Assignee: Magneti Marelli Electrical Limited
    Inventor: John G. W. West
  • Patent number: 4885493
    Abstract: A permanent magnet alternator including a flux diversion member resiliently and magnetically coupled to the permanent magnet rotor for rotation therewith, an auxiliary (control) permanent magnet rotor rigidly coupled to the flux diversion member for rotation therewith, an auxiliary stator disposed about the auxiliary rotor, and control means for variably loading the auxiliary stator to adjust the rotary position of the flux diversion member relative to the main permanent magnet rotor. The flux diversion member comprises a plurality of magnetic flux conducting vanes which coact with the rotor magnets such that variation of its rotary position relative to the rotary position of the permanent magnet rotor varies the stator flux, and hence the alternator output voltage.
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: December 5, 1989
    Assignee: General Motors Corporation
    Inventor: Kalyan P. Gokhale
  • Patent number: 4831300
    Abstract: An alternator/synchronous motor structure provides varying-reluctance paths for radially directed, unidirectional magnetic fields by means of a unique rotor-stator configuration in which inner- and outer-rotor poles and a rotor pole-connecting means surround one end and the inner- and outer-cylindrical surfaces of a hollow cylindrical stator. At least one of the inner or outer poles includes at least one field concentrator member. Optional excitation field may be provided by a stationary winding requiring no brushes for energizing or by permanent magnetization.
    Type: Grant
    Filed: December 4, 1987
    Date of Patent: May 16, 1989
    Inventor: Theodore D. Lindgren
  • Patent number: 4823039
    Abstract: There is disclosed a rotor for an electrical machine, the rotor having a current-carrying winding comprising a plurality of circumferentially distributed winding portions which lie in at least one plane perpendicular to the rotor axis, and extend from a radially inner region to a radially outer region. A commutator is provided by surfaces of the winding portions at the inner region, and the winding is formed from a plurality of conductive sections, each having ends which lie at said outer region, interconnections between the winding sections being made only by way of those ends. Thus, soldered connections made between the winding sections will be remote from the commutator, which is the main source of heat for overheating, and moreover will be at positions where air cooling due to rotor movement is greatest. Air gaps between the winding portions at the outer region aid this cooling affect even further.
    Type: Grant
    Filed: December 18, 1986
    Date of Patent: April 18, 1989
    Inventor: Cedric Lynch
  • Patent number: 4593222
    Abstract: An electric control motor is proposed, which serves to adjust final control elements in closed- or open-loop control systems, in particular for varying the position of throttle devices provided for metering fuels in internal combustion engines. The control motor includes a housing, in which an electromagnetic coil and an armature are disposed, the armature being rotatably supported upon a shaft providing spaced air gaps therewith and with magnetic poles. The magnetic poles are disposed on arcuate conducting bodies, which are disposed in spaced relation on a nonmagnetic carrier body. At ends remote from the magnetic poles, the conducting bodies communicate with one another via a magnetically conductive plate.
    Type: Grant
    Filed: October 15, 1984
    Date of Patent: June 3, 1986
    Assignee: Robert Bosch GmbH
    Inventors: Rainer Burkel, Bernd Taubitz
  • Patent number: 4587449
    Abstract: A permanent magnet rotary dynamo electric machine wherein each permanent magnet pole is equipped with a flux shunt which provides a direct flux path between the airgap at the strong tip region of the pole and the iron circuit upon which the pole is supported, the direct flux path shunting magnetic flux to the iron circuit when the current in the associated winding is low, but being saturated by flux flowing in the opposite direction at high values of winding current.
    Type: Grant
    Filed: November 16, 1983
    Date of Patent: May 6, 1986
    Assignee: Lucas Industried Limited
    Inventor: John G. W. West
  • Patent number: 4575652
    Abstract: A permanent magnet motor having a highly nonuniform reluctance gap between rotor and stator creating reluctance torque which aligns the rotor in narrowly-defined detent zones when the motor coils are de-energized. To overcome the high reluctance torque present at the detent zones upon energizing of the coils, small auxiliary coils are provided adjacent the high reluctance regions of the gap to give the rotor a high immediate starting torque to escape the detent zones and rapidly achieve steady-state angular velocity.
    Type: Grant
    Filed: September 27, 1984
    Date of Patent: March 11, 1986
    Assignee: Synektron Corporation
    Inventor: George P. Gogue
  • Patent number: 4506182
    Abstract: A reluctance motor comprises a stator having two salient poles and a rotor also having two poles and being of soft magnetic material. The stator poles support windings which when current is being supplied generate a magnetic field which tends to set the rotor (16) in a stable position of equilibrium in which the rotor pole and the stator pole coincide. Either or both of the rotor poles and/or either or both of the stator poles are designed so as at high flux density to cause a constriction of the flux in a part of the cross section of the flux path to displace the position of equilibrium and when the flux density is moderate to distribute the flux generally uniformly over the said cross section.
    Type: Grant
    Filed: September 19, 1983
    Date of Patent: March 19, 1985
    Assignee: Aktiebolaget Electrolux
    Inventor: Freddie L. Rohdin
  • Patent number: 4475051
    Abstract: A high performance, low cost variable reluctance stepper motor has an integral structure with a ring and a plurality of aligned salient pole members. A plurality of teeth are located on the face of each pole member. Windings are disposed on alternate ones of the pole members and a high impedance means isolates the pole members from one another. A rotor with a plurality of teeth and a plurality of holes disposed thereon coacts with the pole members and is moved in a step fashion by the sequential energization of the windings. The flux generated by the energization of the windings is confined to a short path and coupling to the remainder of the structure is negligible. Recesses positioned symmetrically around the structure also serve to enhance flux splitting and reduce adjacent flux coupling.
    Type: Grant
    Filed: August 27, 1982
    Date of Patent: October 2, 1984
    Assignee: International Business Machines Corporation
    Inventors: Hi D. Chai, Joseph P. Pawletko
  • Patent number: 4401906
    Abstract: The temperature characteristics of a motor which has a ferrite permanent magnet has been improved. The present motor comprises a stator assembly having at least a yoke for providing a magnetic path and a coil wound on said yoke, and a rotor assembly rotatably inserted in said stator assembly, having at least an elongated spindle rotatably supported by said yoke, and a cylindrical permanent magnet made of a ferrite material pierced by said spindle and being symmetrical wth respect to said spindle, said spindle being made of adjusting alloy or adjusting steel having the magnetic characteristics that the magnetic reluctance of the same increases as the temperature of the same increases, and said yoke is made of steel having the magnetic characteristics that the magnetic reluctance is constant irrespective of the change of the temperature.
    Type: Grant
    Filed: March 10, 1981
    Date of Patent: August 30, 1983
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Minoru Isobe, Hiroshi Kikuchi
  • Patent number: 4347457
    Abstract: A circular-plate permanent magnet, with its one side being magnetized as N-pole while the other as S-pole, which is sandwiched between two rotor yokes made of a magnetic circular plate, is mounted on a rotor shaft as one unit, and this unit makes up the rotor. The stator, which is arranged in a position where its inner surface opposes the outer periphery of the aforesaid rotor across a small air gap, is firmly held between a front cover and a rear cover. Around the outer periphery of the aforesaid rotor yokes, toothed-wheel-like jags which provide the permeance variations are installed. By letting DC current flow stepwise through the stator coils which are wound around the aforesaid stator, the rotor rotates stepwise. With D.sub.1 and D.sub.2 being the outside diameter and the inside diameter respectively of the cylindrical part on the inside diameter side of the front cover and rear cover, D.sub.
    Type: Grant
    Filed: December 12, 1980
    Date of Patent: August 31, 1982
    Assignee: Japan Servo Co.
    Inventor: Masafumi Sakamoto
  • Patent number: 4292532
    Abstract: The system described herein is particularly adapted to convert mechanical energy from a wind or hydraulic driven turbine into electric energy and comprises: an exciter generator and a main generator in a housing traversed by a rotatable shaft; the exciter generator consists of permanent magnet mounted to the housing envelope and of a rotor mounted to the shaft and having a one-phase winding, the rotor being made of non-magnetic material to eliminate cogging and static torque associated with permanent magnet excitation; the main generator consists of a three-phase stator winding on a magnetic core mounted to the housing envelope and of a pole-type rotor mounted to the shaft, the rotor having a winding wound on a magnetic core; a rectifying bridge is rotatably mounted to the shaft and is connected to the one-phase winding of the rotor of the exciter generator and to the winding of the main generator rotor so that the rotation of the shaft as a result of mechanical energy generates a three-phase electric energy
    Type: Grant
    Filed: April 2, 1980
    Date of Patent: September 29, 1981
    Assignee: h.o.p. ConsuLab Inc.
    Inventor: Adrien Leroux
  • Patent number: 4227101
    Abstract: A stepper motor is provided with an adaptor ring for establishing the desired detent position of the motor shaft. The adaptor ring is rotated to a desired mounting hole alignment with respect to the shaft and then the ring is permanently secured to the motor housing.
    Type: Grant
    Filed: June 5, 1978
    Date of Patent: October 7, 1980
    Assignee: Transicoil, Inc.
    Inventors: Vahe H. Malakian, Howard F. Hendricks