Magnetic Reluctance Feature Patents (Class 310/106)
  • Patent number: 11171524
    Abstract: An electromechanical system comprising: a rotor comprising a plurality of teeth spaced about a circumference of the rotor, wherein the teeth of the rotor are equally spaced about the rotor according to a tooth spacing angle, and are skewed in an axial direction such that the circumferential positions of the teeth of the rotor vary along the axial length of the rotor, and first and second stator segments, each extending partway about the rotor and comprising a field winding and poles arranged to magnetically interact with the teeth of the rotor such that an alternating current (AC) back-emf is induced in the field winding upon rotation of the rotor. The poles of the first stator segment are angularly displaced about the rotor from the poles of the second stator segment such that the back-emf induced in the field winding of the first stator segment is phase shifted with respect to the back-emf induced in the field winding of the second stator segment.
    Type: Grant
    Filed: January 3, 2020
    Date of Patent: November 9, 2021
    Assignee: ROLLS-ROYCE plc
    Inventors: Ellis F H Chong, Alexander C. Smith, Yuanpeng Zhou
  • Patent number: 11005317
    Abstract: A rotor body for a rotor of a rotating electric machine, in particular a turbogenerator, has at least one pole axis extending perpendicularly to a longitudinal center axis of the rotor body. At least one section of the rotor body has at least two layers produced from different materials, which layers are arranged in alternation, wherein the materials differ from each other with respect to the electrical conductivity thereof. A layer sequence direction of a layer structure formed by the layers extends perpendicularly to the pole axis and to the longitudinal center axis.
    Type: Grant
    Filed: April 18, 2017
    Date of Patent: May 11, 2021
    Assignee: Siemens Energy Global GmbH & Co. KG
    Inventors: Matthias Kowalski, Christoph Lehmann
  • Patent number: 10985642
    Abstract: A power transmission device includes: a high speed magnet rotor which includes a magnet array which is magnetized in a radial direction; a low speed magnet rotor which includes a magnet array which is magnetized in a circumferential direction; and an inductor rotor which allows magnetic fluxes from the magnet array of the high speed magnet rotor to pass, and the high speed magnet rotor, the low speed magnet rotor and the inductor rotor are concentrically arranged and the magnet array of the low speed magnet rotor is formed such that homopolar surfaces of neighboring magnets face each other in the circumferential direction.
    Type: Grant
    Filed: September 15, 2017
    Date of Patent: April 20, 2021
    Assignee: SANYO DENKI CO., LTD.
    Inventors: Satoshi Sugita, Yuqi Tang, Yasushi Misawa, Shigenori Miyairi
  • Patent number: 10530229
    Abstract: Various embodiments are described herein for switched reluctance machine configurations. In at least one embodiment, a switched reluctance machine configured according to the teachings herein comprises a stator including a predetermined number of salient stator poles (Ns), a rotor rotatably mounted with respect to the stator, with the rotor comprising a plurality of salient rotor poles, and a plurality of coils provided around the predetermined number of stator poles to form at least one phase of the switched reluctance machine, where the rotor poles and the stator poles are symmetrically disposed, and a number of rotor poles is related to Ns and a number of phases according to: i) (Ns/m)k ceil (mod (k,m)/m) for an odd number of phases, and ii) (Ns/m)k ceil (mod(k,m/2)/m/2) for an even number of phases, where m is the number of phases, and k is a configuration index based on Ns and m.
    Type: Grant
    Filed: May 13, 2016
    Date of Patent: January 7, 2020
    Assignee: Enedym Inc.
    Inventors: Berker Bilgin, Ali Emadi
  • Patent number: 10267327
    Abstract: A sealless magnetic drive pump features in improving the stiffness of a stationary shaft. More particularly, the metal magnetic drive pump has an anti-corrosion casing liner. The magnetic drive pump is used in manufacture processes related to corrosive fluid. The pump is especially used in a highly corrosive and high-temperature (up to 200° C.) condition to improve the stiffness of a front support. The stationary shaft includes a metal front support integrated with the pump casing at a pump inlet and encapsulated with a resin enclosure made of a fluoropolymer; a rear shaft seat positioned on a sealed bottom side of a containment shell for offering auxiliary support for the stationary shaft; an impeller including a channel for reducing an inlet flow velocity to offer a low NPSHr.
    Type: Grant
    Filed: April 30, 2017
    Date of Patent: April 23, 2019
    Assignee: ASSOMA INC.
    Inventors: Huan-Jan Chien, Chin-Cheng Wang, Chih-Hsien Shih, Chih-Kuan Shih
  • Patent number: 10190593
    Abstract: A sealless magnetic drive pump features in improving the stiffness of a stationary shaft. More particularly, the metal magnetic drive pump has an anti-corrosion casing liner. The magnetic drive pump is used in manufacture processes related to corrosive fluid. The pump is especially used in a highly corrosive and high-temperature (up to 200° C.) condition to improve the stiffness of a front support. The stationary shaft includes a metal front support integrated with the pump casing at a pump inlet and encapsulated with a resin enclosure made of a fluoropolymer; a rear shaft seat positioned on a sealed bottom side of a containment shell for offering auxiliary support for the stationary shaft; an impeller including a channel for reducing an inlet flow velocity to offer a low NPSHr.
    Type: Grant
    Filed: April 30, 2017
    Date of Patent: January 29, 2019
    Assignee: ASSOMA INC.
    Inventors: Huan-Jan Chien, Chin-Cheng Wang, Chih-Hsien Shih, Chih-Kuan Shih
  • Patent number: 9951778
    Abstract: A structural improvement of the canned pump is to improve the stiffness of a stationary shaft and, according to requirement, to dispose a monitor device. The method for improving the stiffness of the stationary shaft includes axially inserting a shaft metal rear support of the metal structural of a motor rear casing of a canned motor into the inner side of a rotor yoke of an inner rotor of the canned motor, tightly attaching the shaft metal rear support to a rear shaft seat for improving the stiffness of the stationary shaft by longer hold length, and for shortening an arm length of the composite force. The monitor device, used for detecting the wear of a bearing for enhancing the reliability and satisfying the driving requirement, is installed in the ring slot to be protected by the rear shaft seat.
    Type: Grant
    Filed: August 12, 2016
    Date of Patent: April 24, 2018
    Assignee: ASSOMA INC.
    Inventors: Huan-Jan Chien, Chin-Cheng Wang, Chih-Hsien Shih
  • Patent number: 9882442
    Abstract: An axial gap type rotating electric machine, having a stator with first tooth parts protruding in an axial direction and formed in a concentric arc-like manner, and a rotor with magnetic poles arranged in a distributed manner in the circumferential direction, and the magnetic poles include second tooth parts that protrude in the axial direction and are formed in a concentric arc-like manner, the second tooth parts being opposedly arranged so as to respectively engage with the first tooth parts with the intermediation of the air gap. The rotor is incorporated in the rotating member so as to be movable in the axial direction and so as not to be rotatable with respect to the rotating member. The rotating electric machine further includes an urging device that makes the air gap between the rotor and the stator adjustable.
    Type: Grant
    Filed: September 29, 2014
    Date of Patent: January 30, 2018
    Assignee: NIPPON PISTON RING CO., LTD
    Inventors: Masafumi Sakamoto, Shigeyoshi Sato, Shunsuke Takeguchi, Shun Yasuda
  • Patent number: 9755465
    Abstract: The present disclosure relates to rotating electric machines which may be used for industrial applications, to a method for manufacturing a rotor of a synchronous reluctance motor, a rotor of a synchronous reluctance motor, and a synchronous reluctance motor. A rotor of a synchronous reluctance motor according to the present disclosure has a cylindrical rotor body part casted from a superparamagnetic material, and ferromagnetic flux guides arranged inside the casted cylindrical rotor body part. The flux guides are arranged to go through from one side of the outer circumference of the cylindrical rotor part to the other side of the outer circumference of the cylindrical rotor part in the direction of the direct axis of the synchronous reluctance motor.
    Type: Grant
    Filed: October 2, 2014
    Date of Patent: September 5, 2017
    Assignee: ABB Schweiz AG
    Inventors: Jouni Ikäheimo, Jere Kolehmainen
  • Patent number: 9702364
    Abstract: A structural improvement of the canned pump is to improve the stiffness of a stationary shaft and, according to requirement, to dispose a monitor device. The method for improving the stiffness of the stationary shaft includes axially inserting a shaft metal rear support of the metal structural of a motor rear casing of a canned motor into the inner side of a rotor yoke of an inner rotor of the canned motor, tightly attaching the shaft metal rear support to a rear shaft seat for improving the stiffness of the stationary shaft by longer hold length, and for shortening an arm length of the composite force. The monitor device, used for detecting the wear of a bearing for enhancing the reliability and satisfying the driving requirement, is installed in the ring slot to be protected by the rear shaft seat.
    Type: Grant
    Filed: August 12, 2016
    Date of Patent: July 11, 2017
    Assignee: ASSOMA INC.
    Inventors: Huan-Jan Chien, Chin-Cheng Wang, Chih-Hsien Shih
  • Patent number: 9670934
    Abstract: A sealless magnetic drive pump features in improving the stiffness of a stationary shaft. More particularly, the metal magnetic drive pump has an anti-corrosion casing liner. The magnetic drive pump is used in manufacture processes related to corrosive fluid. The pump is especially used in a highly corrosive and high-temperature (up to 200° C.) condition to improve the stiffness of a front support. The stationary shaft includes a metal front support integrated with the pump casing at a pump inlet and encapsulated with a resin enclosure made of a fluoropolymer; a rear shaft seat positioned on a sealed bottom side of a containment shell for offering auxiliary support for the stationary shaft; an impeller including a channel for reducing an inlet flow velocity to offer a low NPSHr.
    Type: Grant
    Filed: October 22, 2012
    Date of Patent: June 6, 2017
    Assignee: ASSOMA INC.
    Inventors: Huan-Jan Chien, Chin-Cheng Wang, Chih-Hsien Shih, Chih-Kuan Shih
  • Patent number: 9599113
    Abstract: A structural improvement of the canned pump is to improve the stiffness of a stationary shaft and, according to requirement, to dispose a monitor device. The method for improving the stiffness of the stationary shaft includes axially inserting a shaft metal rear support of the metal structural of a motor rear casing of a canned motor into the inner side of a rotor yoke of an inner rotor of the canned motor, tightly attaching the shaft metal rear support to a rear shaft seat for improving the stiffness of the stationary shaft by longer hold length, and for shortening an arm length of the composite force. The monitor device, used for detecting the wear of a bearing for enhancing the reliability and satisfying the driving requirement, is installed in the ring slot to be protected by the rear shaft seat.
    Type: Grant
    Filed: October 22, 2012
    Date of Patent: March 21, 2017
    Assignee: ASSOMA INC.
    Inventors: Huan-Jan Chien, Chin-Cheng Wang, Chih-Hsien Shih
  • Patent number: 8952589
    Abstract: In a rotating electrical machine of axial-gap type in which a stator and a rotor are opposed to each other in arrangement and winding axis is parallel with a rotating shaft direction, the stator has an “m” protruding in the rotating shaft direction are distributed along a circumferential direction thereof, in which the winding pole is formed of a magnetic member having a plurality of teeth in a circular-arc shape in a diameter direction, and wherein the rotor is formed of a magnetic member having a plurality of teeth in a circular-arc shape in a diameter direction, and the number of the teeth of the stator and the rotor are arranged in a manner opposite to each other through air gap so as to be engaged with each other. The stator and the rotor are opposed on both sides of the rotor and the stator.
    Type: Grant
    Filed: December 19, 2012
    Date of Patent: February 10, 2015
    Assignee: Nippon Piston Ring Co., Ltd
    Inventors: Masafumi Sakamoto, Shigeyoshi Sato, Shunsuke Takeguchi
  • Patent number: 8441223
    Abstract: Disclosed herein is a torque control method for a high-speed Switched Reluctance Motor (SRM), which controls a torque in the high-speed operation of a 2-phase SRM. In the torque control method for a high-speed SRM, a positive torque (T*mA) of an active phase (A phase) of the two phases of the SRM is compensated for based on a negative torque attributable to an inactive phase (B phase) of two phases during a compensation control enable interval (ENA) ranging from a time point at which the active phase (A phase) is turned on to a time point at which tail current of the inactive phase (B phase) remains. Accordingly, the present invention can remarkably reduce a torque ripple occurring in high-speed operation mode in consideration of the influence of a negative torque attributable to tail current.
    Type: Grant
    Filed: February 9, 2011
    Date of Patent: May 14, 2013
    Assignee: Kyungsung University Office of Industry-Academy Cooperation
    Inventors: Jin-Woo Ahn, Dong-Hee Lee
  • Patent number: 8242652
    Abstract: A coupling device for the transmission of torque. The coupling device includes a drivable rotor part, an output shaft rotatably connected with an armature part, a hysteresis part disposed on the armature part, permanent magnets configured to generate a magnetic field through which magnetic field a torque can be transmitted from the rotor part to the armature part, a stator part in which an electromagnet is disposed, the electromagnet being configured to induce a magnetic flux in the rotor part so as to adjust a torque from the rotor part to the armature part, and a synchronous coupling disposed between the stator part and the armature part.
    Type: Grant
    Filed: May 29, 2008
    Date of Patent: August 14, 2012
    Assignee: Pierburg GmbH
    Inventors: Albert Genster, Andreas Burger, Gerd Schuessler, Stefan Pedall, Michael Prokopp
  • Patent number: 8120215
    Abstract: A motor and a control unit therefor comprise: salient rotor poles and salient stator poles, which are arranged along circumferences of phases A, B and C with an even interval therebetween; magnetic paths for passing magnetic fluxes, the paths permitting the magnetic fluxes passing through the salient rotor and stator poles of each phase to return to the rotor side; and substantially looped windings arranged between the salient stator poles of individual phases and the magnetic paths for passing magnetic fluxes, wherein currents are supplied to the windings in synchronization with the rotational position of the rotor to thereby output torque. Since the structures of the stator, the rotor and the windings are simple, productivity is enhanced, whereby high quality, small size and low cost can be realized.
    Type: Grant
    Filed: May 16, 2006
    Date of Patent: February 21, 2012
    Assignee: Denso Corporation
    Inventor: Masayuki Nashiki
  • Publication number: 20110215668
    Abstract: A magnetic transmission assembly is adapted to integration with a motor or generator. The magnetic transmission assembly includes a rotor, a stator, and a magnetically conductive element. The rotor and the stator are sleeved coaxially and respectively have R and ST1 pole pairs. The magnetically conductive element is located between the rotor and the stator, and has permeable regions. When the magnetically conductive element is actuated, the magnetically conductive element selectively enables PN1 or PN2 permeable regions to be corresponding to the rotor and the stator. The permeable regions corresponding to the rotor and the stator interact with magnetic fields of the R and ST1 pole pairs to generate a predetermined variable-speed ratio. The magnetic transmission assembly can be integrated into the motor, so as to improve the drive power density.
    Type: Application
    Filed: October 14, 2010
    Publication date: September 8, 2011
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Ming Tsan Peng, Li Ju Cheng
  • Patent number: 7898123
    Abstract: The permanent magnet type rotary machine is capable of reducing cogging torque caused by variation of amounts of magnetic flux in magnetic circuits. The permanent magnet type rotary machine comprises: a stator constituted by stator units, which are coaxially stacked and in each of which a coil is sandwiched between stator yokes; and a rotor including a permanent magnet having magnetic poles, which respectively face magnetic pole teeth of the stator yokes, the rotor being rotatably supported by an output shaft. The stator units in one phase is divided into n (n is an integer one or more), and magnetic centers of at least one pair of the magnetic pole teeth of the adjacent stator yokes, which are vertically arranged, are shifted with a prescribed phase difference so as to mutually cancel their cogging torque.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: March 1, 2011
    Assignee: Shinano Kenshi Kabushiki Kaisha
    Inventor: Hiroaki Usui
  • Publication number: 20100207473
    Abstract: A coupling device for the transmission of torque. The coupling device includes a drivable rotor part, an output shaft rotatably connected with an armature part, a hysteresis part disposed on the armature part, permanent magnets configured to generate a magnetic field through which magnetic field a torque can be transmitted from the rotor part to the armature part, a stator part in which an electromagnet is disposed, the electromagnet being configured to induce a magnetic flux in the rotor part so as to adjust a torque from the rotor part to the armature part, and a synchronous coupling disposed between the stator part and the armature part.
    Type: Application
    Filed: May 29, 2008
    Publication date: August 19, 2010
    Applicant: PIERBURG GMBH
    Inventors: Albert Genster, Andreas Burger, Gerd Schuessler, Stefan Pedall, Michael Prokopp
  • Publication number: 20100186179
    Abstract: A workpiece system with a reciprocating motion which includes a motor assembly for producing an output drive signal with a periodic force pulse. The drive signal is coupled to a driven member assembly through a magnetic arrangement, wherein the driven member assembly has a workpiece mounted thereon with a return spring assembly. The driven member assembly has a resonant mechanical frequency. As the RPM of the motor increases from zero following startup, the drive signal frequency increases to the point very near resonance, where the energy from the drive signal is transferred into the reciprocating motion of the driven assembly, producing an effective amplitude of workpiece motion.
    Type: Application
    Filed: June 30, 2006
    Publication date: July 29, 2010
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Kevin Miller, John Pace, Patrick Headstrom, Wolter Benning
  • Patent number: 7741746
    Abstract: A magnetic slip clutch has an outer rotor and an inner rotor, one of the rotors includes permanent magnets, and one of the rotors includes slots, and both rotors are located coaxially to one another; the outer rotor is embodied as a hollow cylinder open on one end, which cylinder includes a face-end covering with a central recess, by which the hollow cylinder can be located on a shaft, and the inner rotor is embodied as a solid cylinder, which is located inside the outer rotor, and a shaft can be located in a central recess in the solid cylinder, and a separate shaft is connectable to each rotor, so that the axis of rotation of the two separate shafts is identical, and a torque transmission is possible from one shaft to the other shaft by both rotors.
    Type: Grant
    Filed: December 17, 2007
    Date of Patent: June 22, 2010
    Assignee: Robert Bosch GmbH
    Inventor: Ingolf Groening
  • Publication number: 20100132138
    Abstract: When, according to the invention, constructing a drive system for rotating a cleaning head in a tank and allowing the system to comprise a hysteresis coupling having two magnetic parts, one being present inside the liquid space (4) and the other outside the liquid space, respectively, a completely liquid-tight separation between the housing (2) and a gear (14) may be ensured. The magnetic part (8, 18) of the hysteresis coupling may be formed by electromagnets, and with a displaceable (13) position of one part relative to the other part (11,19), the coupling may be adjusted with respect to the transferred torque and/or speed.
    Type: Application
    Filed: February 9, 2010
    Publication date: June 3, 2010
    Applicant: ALFA LAVAL TANK EQUIPMENT A/S
    Inventors: Hans Erik JØRGENSEN, Leon HJORSLEV
  • Patent number: 6700265
    Abstract: An eddy current retarder having a rotor part of the retarder with symmetry of revolution about the axis of the engine shaft so that it has a peripheral face facing a peripheral face of the stator part, the inductor of the retarder having at least one electromagnetic winding. Thus, the Eddy current retarder maintains a compact structure while at the same time allowing simple and easy control over its magnetic flux by virtue of the presence of electromagnets.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: March 2, 2004
    Assignee: Telma
    Inventor: Stefan Bouissou
  • Patent number: 6628029
    Abstract: A control device for rotating a tube supporting a roller member to be wound onto or unwound from the tube has at least one electric motor housed in the tube and drive mechanism for transmitting the motion from the motor to the supporting tube. The motor is an electric three phase motor having at least four poles. The drive mechanism preferably has a single-stage mechanical reduction gear such as a planocentric reduction gear.
    Type: Grant
    Filed: March 23, 2001
    Date of Patent: September 30, 2003
    Inventor: Paolo Astegno
  • Patent number: 6283901
    Abstract: A device for effecting resistance is incorporated into an exercise or rehabilitation machine and is formed of an excited magnetic cylinder, an excited magnetic coil, a rotary cylinder, and two support frames. As the excited magnetic coil is connected to the alternating current power source in conjunction with a control switch, the exercise or rehabilitation machine is provided with a magnetic resistance of a predetermined magnitude. The excited magnetic cylinder is provided in one side with an annular wavy magnetic interstice for guiding the magnetic line toward the rotary cylinder, thereby resulting in a magnetic resistance causing the fixed excited magnetic cylinder and the rotary cylinder to attract each other. The rotary cylinder is connected to a link device of the exercise or rehabilitation machine, so as to provide the exercise or rehabilitation machine with a resistance.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: September 4, 2001
    Inventor: Huang Tung Chang
  • Patent number: 6217298
    Abstract: The transmission comprises at least three induction systems which are arranged axially one after the other or coaxially one above the other and which can be rotated about a common axis of rotation (4). The induction system in the middle is in each case provided in the side faces with a winding which are connected to one another and are executed in such a manner that the magnetic rotary fields which arise by means of relative movement between the induction system in the middle and one adjacent induction system effect a relative movement between the induction system in the middle and the other adjacent induction system in order to produce an output movement.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: April 17, 2001
    Assignee: Sulzer Innotec AG
    Inventor: Erich Kläui
  • Patent number: 6208053
    Abstract: A hysteresis slip clutch having an adjustable stall torque is provided. The clutch components include first and second rotors, with a housing at least partially enclosing the rotors. An annular permanent magnet is rigidly mounted on the first rotor and an annular hysteresis sleeve is rigidly mounted to the second rotor. The first and second rotors are mounted within the housing such that the magnet and hysteresis sleeve are concentrically located and axially aligned with one another within the housing. In this orientation, magnetic flux from the magnet penetrates the hysteresis sleeve and magnetic hysteresis developed within the hysteresis sleeve acts to oppose relative angular motion between the first and second rotors. The magnetic hysteresis establishes a torque by which angular motion of the first rotor is transferred to the second. A annular magnetic shunt is adjustably mounted to the housing.
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: March 27, 2001
    Assignee: MPC Products Corporation
    Inventor: Craig Scott
  • Patent number: 5847478
    Abstract: A self holding type connecting device comprising an armature which is disposed movably in an axial direction, a magnetic path member having a cross section formed along a closed loop and having an axial space wherein axial movement of the armature is permitted, a permanent magnet secured to the magnetic path member and forming two kinds of magnetic flux which pass through the armature and the magnetic path member, an electric magnetic coil which forms magnetic flux for moving the armature in an axial direction against the two kinds of magnetic flux, and switch for switching direction of the magnetic flux from the electric magnetic coil. In the device, decrease of connecting force due to abrasion of pads does not occur and power consumption can be remarkably reduced.
    Type: Grant
    Filed: February 26, 1997
    Date of Patent: December 8, 1998
    Assignee: Teijin Seiki Co., Ltd.
    Inventors: Hiroshi Usui, Shingo Nakagawa
  • Patent number: 5803404
    Abstract: The damper is comprised of a set of core rotor magnets arranged in an opposing north/south configuration. A conducting material cylindrically encircles the rotor magnets. A set of stator magnets laterally encircle the conducting material and are arranged in the same manner as the rotor magnets. A system of gears are coupled to the damper shaft and control the rotation of the rotor magnets such that they can be positioned relative to the stator magnets to set up the desired damping torque. As the rotor and stator magnets of opposite polarity approach each other, the eddy-current in the rotating conducting material increases causing the conducting material to generate a field in response to the eddy-current. The damping torque is caused by the magnetic force generated when the induced field in the material and the stator/rotor field attempt to line up.
    Type: Grant
    Filed: January 23, 1996
    Date of Patent: September 8, 1998
    Assignee: MPC Products, Inc.
    Inventors: Anton A. Petrou, Craig H. Scott, Stephen B. Warner, Jerry D. Hielkema
  • Patent number: 5714820
    Abstract: A magnetic coupling includes a cylindrical housing, a spindle, an adjusting plate, two pairs of permanent magnet discs, two hysteresis material discs, and a screw member. The spindle is rotatably supported at its axial position by the housing. The adjusting plate is rotatably supported by the spindle to partition an interior of the housing into two sections in a direction of the spindle. The two pairs of permanent magnets are provided in the two corresponding sections to respectively oppose each other. One of each pair of permanent magnet discs is fixed in the housing and the other thereof is fixed to the adjusting plate. Each permanent magnet disc has magnetic poles with polarities that alternate in a circumferential direction. The hysteresis material discs are fixed to the spindle and arranged between the corresponding pairs of permanent magnet discs at a predetermined gap. The screw member fixes the adjusting plate to the housing.
    Type: Grant
    Filed: September 5, 1996
    Date of Patent: February 3, 1998
    Assignee: Ogura Clutch Co., Ltd.
    Inventors: Takashi Mitsuhashi, Sakae Takakusagi
  • Patent number: 5432390
    Abstract: A switched reluctance motor includes a stator having a central bore for rotation of a rotor therein. The stator has four equally spaced teeth extending radially inwardly from the yoke of the stator to define the central bore. A rotor assembly for rotation in the central bore of the stator is included. The rotor assembly has three teeth extending radially outwardly from the central axis of the motor to terminate in close proximity to the stator teeth. Stator windings associated with the stator teeth generate a magnetic field in the central bore to cause rotation of the rotor assembly.
    Type: Grant
    Filed: May 15, 1992
    Date of Patent: July 11, 1995
    Assignee: Emerson Electric Co.
    Inventor: Ilija J. Obradovic
  • Patent number: 5304882
    Abstract: A new class of doubly-salient variable reluctance motors which provides greater output torque, higher efficiency, quicker response, and a simple structure in comparison to conventional reluctance motors by utilizing a specific stator/rotor pole arrangement and by altering the magnetic structure of the motor by using permanent magnets to provide a linearly increasing flux linkage over the entire area of pole overlap.
    Type: Grant
    Filed: May 11, 1992
    Date of Patent: April 19, 1994
    Assignee: Electric Power Research Institute, Inc.
    Inventors: Thomas A. Lipo, Yuefeng Liao
  • Patent number: 5296773
    Abstract: A rotor assembly for a synchronous reluctance dynamo/motor machine has a plurality of axial laminations comprised of alternate magnetic and non-magnetic materials. The rotor has an end cap on each axial end which engages the stepped axial ends of the laminations.
    Type: Grant
    Filed: April 20, 1993
    Date of Patent: March 22, 1994
    Assignee: General Motors Corporation
    Inventors: Ahmed M. El-Antably, Donald Klemen
  • Patent number: 5289065
    Abstract: A stepper motor having an internally toothed ring gear acting as a stator which is contacted by one or more pinion gears supported by a carrier. The ring gear stator is made up of several sets of teeth which are separately magnetically polarized to move the pinion gears about the ring gear. Three toroidal coils are preferably provided to charge three different sets of teeth which are arranged in a repeating series of three about the ring gear. Alternatively, a linear actuator can be provided to provide a linear output. The teeth may also include an individual coil wherein sets of teeth can be electromagnetically biased into a north or south polarity or remain neutral.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: February 22, 1994
    Assignee: Ford Motor Company
    Inventor: James E. Marshall
  • Patent number: 5256923
    Abstract: A switched reluctance motor (10) provides position and speed detection without a shaft position sensor. At least one of the stator pole faces (54) and/or at least one of the rotor pole faces (60) has an irregularity such as a notch (52 and/or 58) providing a perturbation or blip (70, 82) in the inductance profile (72, 76, 84) of the motor (10) during rotation of the rotor (14) indicative of the position of the rotor (14) relative to the stator (12). The frequency of the perturbations indicates motor speed.
    Type: Grant
    Filed: May 11, 1992
    Date of Patent: October 26, 1993
    Assignee: A. O. Smith Corporation
    Inventors: Ronald P. Bartos, Timothy H. Houle, J. Herbert Johnson
  • Patent number: 5187401
    Abstract: An improved electric motor has a stator, and a hysteresis cylindrical ring formed of magnetic metallic material disposed within the stator cylindrical core with an annular air space between the hysteresis cylindrical ring and the stator core, and a rotor cylindrical sleeve formed of non-magnetic material relatively rotatably mounted within the hysteresis cylindrical ring on a suitable shaft. The improvement includes several interrelated elements. Firstly, the hysteresis cylindrical ring has four longitudinal, generally-rectangular slots spaced 90.degree. apart, and extending from an inner surface of the hysteresis cylindrical ring. Secondly, a permanent magnet is provided only in each of the slots. Thirdly, the rotor cylindrical sleeve has 4 longitudinally-extending, non-magnetically-retentive projections thereon, the projections being spaced 90.degree. apart. The rotor cylindrical sleeve thereby provides longitudinally-extending, annular air duct in each of the 4 sections.
    Type: Grant
    Filed: December 24, 1990
    Date of Patent: February 16, 1993
    Inventor: M. Azizur Rahman
  • Patent number: 5173651
    Abstract: A direct current brushless electric motor has a rotor, and a stator with inwardly extending teeth, between each pair of which a winding slot is defined. The radially inward face of each tooth has a dummy slot shaped so the reluctance forces between rotor and stator due to the presence of the dummy slots are the same as those due to the winding slots. Motor control arrangement incorporates a current feedback loop based on the incoming phase of each phase combination in the phase energization sequence in a driving mode and phase changeover may be initiated by Hall devices, two for each transition point, underlying the axial ends of the rotor magnets. The control arrangement may incorporate a pulse width modulation power supply permitting the establishment of bias currents under motor standstill conditions.
    Type: Grant
    Filed: July 15, 1988
    Date of Patent: December 22, 1992
    Assignee: Kollmorgen Technologies Corporation
    Inventors: Maurice Buckley, Arthur Stone, Aengus Murray
  • Patent number: 5168190
    Abstract: A reluctance-type motor in which two or more three-phase, half-wave reluctance-type motors are juxtaposed within an outer casing (42), the number of magnetic poles (16a, . . .) and salient poles per motor decreases. Accordingly, a long and narrow motor having a small diameter can be obtained. With a construction in which n number of three-phase, half-wave motors are juxtaposed, the output torque is multiplied by n. Further, by providing a phase difference of 120/n degrees for the output torque of each motor, the torque ripple can be made small and the characteristics at the start-up time become good. By feeding back the magnetic energy in an exciting coil to the D.C. power supply of the applied high voltage, the magnetic energy is extinguished rapidly to prevent a counter-torque from occurring, and a magnetic energy is stored rapidly by the applied high voltage to prevent a reduced torque from occurring.
    Type: Grant
    Filed: April 25, 1991
    Date of Patent: December 1, 1992
    Assignee: Kabushikigaisha Sekogiken
    Inventor: Itsuki Bahn
  • Patent number: 5148090
    Abstract: This invention determines the configurations of a rotor (10) and a stator (12) and conductance periods and conductance phases of the conductance currents to obtain a smooth rotation of a variable reluctance motor as an AC servo motor. When the number of phases of a motor is m, the number of salient poles (R.sub.j) of a rotor (10) is an integer n, and the number of salient poles (S.sub.k) of a stator (12 ) is r.multidot.m, n is a whole multiple of r, and where the configuration of the stator salient pole (S.sub.k) is rectangular and the configuration of the rotor salient pole (R.sub.j) is sinusoidal, AC sine wave currents shifted by 2n.pi./(r.multidot.m) each and having two times as large a period as that of a magnetic permeance fluctuation caused by a rotation of the rotor (10), are conducted to the phases of the motor.
    Type: Grant
    Filed: May 23, 1990
    Date of Patent: September 15, 1992
    Assignee: Fanuc Ltd.
    Inventors: Hideaki Oku, Takeshi Nakamura
  • Patent number: 4831298
    Abstract: An electromagnetic torque transmission structure for transmitting torque from one shaft to a second aligned shaft, the structure including an excitation-rotor attached to a first shaft, an induction-rotor attached to a second shaft, and a magnetic field-exciter. An inner pole, an outer pole and a pole-connecter of the excitation-rotor surround the inner and outer surfaces and one end of the hollow induction-rotor cylinder. At least an inner or outer pole includes field concentrators. A stationary winding with magnetic circuitry provides an excitation field associated with the excitation-rotor. Magnetic fields from induced currents in the induction-rotor react with fields from the excitation-rotor to provide torque transmission between shafts.
    Type: Grant
    Filed: December 4, 1987
    Date of Patent: May 16, 1989
    Inventor: Theodore D. Lindgren
  • Patent number: 4722661
    Abstract: A magnetic-drive centrifugal pump comprises a driving motor, a pump shaft, an impeller, a rotor with a sleeve portion to which is connected the impeller, the rotor and impeller being rotatably mounted on the pump shaft, and a pump casing consisting of a front casing and a rear casing. The impeller is driven by a magnetic coupling formed by a driving magnet provided on a magnet holder connected to the driving motor and an impeller magnet provided in the rotor. The sleeve portion has an outer diameter smaller than an outer diameter of a main portion of the rotor. The rear casing has at a location opposite to the sleeve portion a first inner diameter enabling an outer circumference of the main portion of the rotor to slide therein, and at a location opposite to the main portion of the rotor a second inner diameter larger than the first inner diameter.
    Type: Grant
    Filed: October 9, 1985
    Date of Patent: February 2, 1988
    Assignee: NGK Insulators, Ltd.
    Inventor: Motoshige Mizuno