Synchronous Patents (Class 310/162)
  • Patent number: 6455970
    Abstract: Described herein is a multi-phase transverse flux machine, which comprises a stator with essentially U-shaped and I-shaped cores (1, 2) of a soft-magnetic material and respectively one stator winding (3) for each phase that generates a magnetic flux in these cores, as well as a rotor with circular magnetic return path (4). The phases of the stator are magnetically separated. The rotor contains electrically conductive material (5, 6) in each of the phases, wherein the electrically conductive material of at least two phases is arranged and is interconnected in the rotor, such that if an alternating current flows through the stator windings of these phases, a current generating a starting torque for the rotor is induced in the electrically conductive material. The at least two phases thus electrically form a rotating magnetic field machine in the rotor.
    Type: Grant
    Filed: September 19, 2000
    Date of Patent: September 24, 2002
    Assignee: Bombardier Transportation GmbH
    Inventors: Uwe Shäfer, Harald Neudorfer
  • Publication number: 20020125775
    Abstract: A hybrid synchronous motor comprising a rotor and stators, wherein the stator has at least one assembly (7) having a structure in which ferromagnetic rings (2, 3) formed with cogs on the both inner and outer circumferences thereof, are arranged coaxially, and a coil winding (8) is wound on the assembly (7) so as to be positioned between cogs. The hybrid synchronous motor exhibits a high magnetic flux density in the air gap as the result of transverse magnetic flux of the permanent magnets combined with longitudinal magnetic flux of the coils and high active surface at the air gap due to double (inner and outer) air gaps. Further, since it contains only a single set of stator coils and it has merely a small number of assembling parts and conventional techniques of fabrication may be applied, the motor is cheap in construction. Furthermore, the motor exhibits an excellent energy efficiency due to only small ohmic losses in the coils.
    Type: Application
    Filed: September 27, 2001
    Publication date: September 12, 2002
    Inventor: Andrej Detela
  • Patent number: 6429554
    Abstract: An electric motor having a stationary annular stator with wound stator poles and a rotatably mounted rotor having annularly distributed permanent magnets or electromagnets of alternate polarity, wherein the stator is composed of a plurality of separate stator segments with their own, preferably three-phase current connections, wherein each stator segment is fed by way of the respective current connections from its own frequency converter.
    Type: Grant
    Filed: October 10, 2000
    Date of Patent: August 6, 2002
    Assignee: Innova Patent GmbH
    Inventors: Reinhard Albrich, Elmar Fuchs
  • Patent number: 6426577
    Abstract: Rotary synchronous machine includes a stator and a rotor. The stator includes a magnetic field core and an armature core magnetically separated from each other. The rotor includes a plurality of magnetic substance segments which are magnetically separated from each other in a direction of rotation but are magnetically coupled with both of the magnetic field core and armature core. The rotor and magnetic field core are arranged to cause an axial thrust to the rotor depending on the intensity of electric currents passed through filed windings. Namely, the rotor and magnetic field core are arranged in such a manner that magnetic attraction (magnetic coupling) occurs between the rotor and the magnetic field core in a same direction as a rotational axis or at a predetermined non-normal angle relative to the rotational axis.
    Type: Grant
    Filed: July 28, 1999
    Date of Patent: July 30, 2002
    Assignee: Nisso Electric Corporation
    Inventors: Tokuzou Sekiyama, Satoru Matsubara, Satoshi Nishida, Hiroshi Shibuya
  • Patent number: 6404089
    Abstract: This device is a brushless high-voltage electrical generator, requiring suitable means of input rotary torque, for purposes of producing a very-high-energy external electrodynamic field or continuous quasi-coherent DC corona or arc discharge of uniform current density which completely encloses the machine's conductive housing. This housing is divided into distinct electrical sections and contains a flat conductive rotor which electrically links separate negative and positive housing sections and upon which a plurality of toroidal generating coils are rotatably mounted. Circular arrays of stationary permanent magnets are affixed within the housing which induce a constant DC voltage within said coils upon their rotation.
    Type: Grant
    Filed: July 21, 2000
    Date of Patent: June 11, 2002
    Inventor: Mark R. Tomion
  • Patent number: 6376958
    Abstract: Provided are a super-high speed permanent magnet type synchronous motor which causes less loss in a rotor even though it is driven by an inverter adapted to be operated with a fundamental frequency around 1 kHz, and an air compressor. The air compressor having a super-high speed permanent magnet type synchronous motor which is composed of a stator in which armature windings are wound in a plurality of slots formed in a stator core, and a rotor including a shaft made of a conductive magnetic material, a conductive permanent magnet laid around the outer periphery of the shaft, and a reinforcing member made of carbon fibers and laid around the outer periphery of the permanent magnet, wherein a laminated electromagnetic steel sheet is interposed between the shaft and the permanent magnet, and the laminated electromagnetic steel sheet has a high tensile strength higher than 70 kg/mm2.
    Type: Grant
    Filed: August 10, 2000
    Date of Patent: April 23, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Haruo Koharagi, Tsukasa Taniguchi, Kouki Yamamoto, Satoshi Kikuchi, Miyoshi Takahashi, Haruo Miura, Yasuo Fukushima, Masaharu Senoh
  • Patent number: 6359365
    Abstract: A superconducting winding includes a pair of superconducting winding sections electrically connected at a node and bypass circuitry connected between the node and electrical ground and configured to allow current to flow to electrical ground when a voltage across the superconducting winding exceeds a predetermined threshold voltage. In certain embodiments, the bypass circuitry includes a switching device (e.g., zener diode) having an open position and a closed position, the switch in the closed position to allow current flow when the voltage across the superconducting winding exceeds the predetermined threshold voltage.
    Type: Grant
    Filed: August 4, 2000
    Date of Patent: March 19, 2002
    Assignee: American Superconductor Corporation
    Inventor: Swarn S. Kalsi
  • Patent number: 6329734
    Abstract: A permanent magnet-reluctance type rotating machine includes an annular stator having armature windings arranged on an inner periphery of the stator, a rotor rotatably arranged inside the stator and a plurality of permanent magnets disposed in a rotor core. One permanent magnet defining each pole is divided into two magnet pieces in a direction parallel to the magnetizing direction of the permanent magnets. Owing to the division of the magnet, the mass of each permanent magnet becomes small in comparison with that of the conventional machine, so that the centrifugal force applied on the magnet holes can be reduced. Consequently, the stress generating in the rotor core is decreased to allow the rotating machine to rotate at a higher speed.
    Type: Grant
    Filed: February 22, 2000
    Date of Patent: December 11, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Norio Takahashi, Kazuto Sakai, Yutaka Hashiba, Masanori Arata, Hirotsugu Tsutsui
  • Publication number: 20010045787
    Abstract: A permanent magnet synchronous motor includes a stator and a permanent magnet excited rotor, with the stator provided with a winding which has cyclically repeating winding factors |&xgr;p|=0.945, |&xgr;5p|=0.140, and |&xgr;7p|=0.
    Type: Application
    Filed: December 6, 2000
    Publication date: November 29, 2001
    Applicant: SIEMENS AKTIENGESELLSCHAFT
    Inventor: Gerhard Huth
  • Patent number: 6300700
    Abstract: A motor comprises a stator core having plural teeth and slots provided among the teeth, a winding applied on the teeth by a turn, and a rotor incorporating plural permanent magnets. The rotor is rotated and driven by utilizing reluctance torque in addition to magnetic torque. Since the winding is not crossed, the size of the coil end is reduced.
    Type: Grant
    Filed: March 21, 2000
    Date of Patent: October 9, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Noriyoshi Nishiyama, Tomokazu Nakamura, Yasufumi Ikkai, Yukio Honda, Hiroshi Murakami, Shinichiro Kawano
  • Patent number: 6300703
    Abstract: This invention pertains to a rotor core (6) in which a plurality of core sheets (1) are laminated on one another on a rotor shaft (4). A plurality of slits (3, 7) and a plurality of strips (2) are alternately arranged in a radial direction of each of the core sheets (1) so as to convexly confront a center of each of the core sheets (1) such that an outer peripheral rim (10) is formed between an outer peripheral edge of each of the core sheets (1) and each of opposite ends of each of the slits (3, 7). A stress concentration portion (11) which is provided at a portion (10a) of the outer peripheral rim (10) and has a width (L1) larger than that of the remaining portions of the outer peripheral rim (10).
    Type: Grant
    Filed: November 23, 1999
    Date of Patent: October 9, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shinichiro Kawano, Hiroyuki Kiriyama, Yukio Honda, Hiroshi Sawada, Noriyoshi Nishiyama
  • Patent number: 6278212
    Abstract: An exciter includes a concentrically laminated disk with AC windings, and a stationary disk with DC excitation windings and a plurality of DC excitation poles. The stationary disk is spaced from the laminated disk to form a gap therebetween. Upon rotation of the laminated disk, a DC current applied to the DC excitation poles produces an AC current in the AC windings. The AC current passes through a rotating rectifier to produce DC current, which supplies the generator or motor field. The stationary disk also includes pilot AC windings. The DC excitation poles are on a first face of the stationary disk and the AC windings are on a second face of the stationary disk. A rectifier is coupled between the pilot AC windings and the DC excitation windings of the stationary disk. A pilot disk with permanent magnets is spaced from the stationary disk to form a gap therebetween. Upon rotation of the pilot disk, an AC current is created in the pilot AC windings of the stationary disk.
    Type: Grant
    Filed: July 7, 1999
    Date of Patent: August 21, 2001
    Assignee: American Superconductor Corp.
    Inventor: Swarn S. Kalsi
  • Patent number: 6259176
    Abstract: A multi-phase outer-type permanent magnet stepping motor including a rotor constituted by a cylindrical permanent magnet assembly in which N (north) and S (south) poles are magnetized alternately on an inner circumferential surface of the rotor. Stator cores respectively having pole teeth are disposed in opposition to the N or S poles of the rotor through a predetermined gap. Further, excitation coils are wound in the stator cores for magnetizing the stator cores to thereby rotate the rotor such that, when a number of the stator cores is 3 and the magnetization pitch of the permanent magnet assembly is P, pole teeth of the stator cores are arranged so that the pole teeth of one stator core is shifted by an angle of 2P/3 from the pole teeth of an adjacent stator core.
    Type: Grant
    Filed: January 28, 1999
    Date of Patent: July 10, 2001
    Assignee: Japan Servo Co., LTD
    Inventors: Kouki Isozaki, Naotugu Sato, Yuuichi Tsuda, Junji Rokunohe, Ayako Shimura
  • Patent number: 6259181
    Abstract: This invention pertains to a rotor core (6) in which a plurality of core sheets (1) are laminated on one another on a rotor shaft (4). A plurality of slits (3, 7) and a plurality of strips (2) are alternately arranged in a radial direction of each of the core sheets (1) so as to convexly confront a center of each of the core sheets (1) such that an outer peripheral rim (10) is formed between an outer peripheral edge of each of the core sheets (1) and each of opposite ends of each of the slits (3, 7). A stress concentration portion (11) which is provided at a portion (10a) of the outer peripheral rim (10) and has a width (L1) larger than that of the remaining portions of the outer peripheral rim (10).
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: July 10, 2001
    Assignee: Matsushita Electric Industrial Co.
    Inventors: Shinichiro Kawano, Hiroyuki Kiriyama, Yukio Honda, Hiroshi Sawada, Noriyoshi Nishiyama
  • Patent number: 6242834
    Abstract: A flux concerning electrical machine has a stator and a rotor, the stator including on its face a series of notches housing a series of stator coils, and further including a series of housings for excitation means, and the rotor including a plurality of flux commutator teeth for selectively making pairs of closed magnetic circuits through the stator coils. In accordance with invention the stator includes a plurality of independent stator coils defining as many phases and located in a series of individual cells angularly distributed on its circumference and the rotor teeth are equi-angularly spaced so that the angular positions of the various pairs of teeth have predetermined phases relative to the various individual cells. The invention is applicable in particular to brushless alternators for motor vehicles.
    Type: Grant
    Filed: December 14, 1998
    Date of Patent: June 5, 2001
    Assignee: Valeo Equipements Electriques Moteur
    Inventor: Dokou Antoine Akemakou
  • Patent number: 6239530
    Abstract: A sub-synchronous reluctance electrical machine having a stator provided with a core comprised of an assembly of magnetically uncoupled or weakly coupled sectors of ferromagnetic plates having longitudinal teeth arranged on the face thereof turned towards the rotor and provided with grooves to respectively house a winding. This winding is comprised of a plurality of coils surrounding a respective sector of the ferromagnetic material of stator in a properly distributed manner, so as to generate a magnetic field whenever this winding is energized. The sub-synchronous reluctance electrical machine possesses as an integral part thereof said rotor which in turn is provided with a core of magnetic plates having longitudinal teeth uniformly arranged along the face thereof turned towards the stator, said teeth being in a number different from the number of teeth of the stator.
    Type: Grant
    Filed: September 29, 1999
    Date of Patent: May 29, 2001
    Assignee: Elevadores Atlas-Schindler S/A
    Inventor: Fernando Garcia
  • Patent number: 6239526
    Abstract: A flux barrier type synchronous reluctance motor in which a plurality of flux barriers are provided in a rotor, of which a plurality of ribs form the end portion of each of the flux barriers, wherein assuming that both ends of a single flux barrier are a first and a second rib, when the first rib faces the center of a slot of a stator, the second rib faces the center of a teeth of the stator.
    Type: Grant
    Filed: March 21, 2000
    Date of Patent: May 29, 2001
    Assignee: LG Electronics, Inc.
    Inventors: Jae Yoon Oh, Dal Ho Jung
  • Patent number: 6236135
    Abstract: To provide a toroidal core type actuator having a stator unit which is increased in winding density, is improved in methods of the terminal handling after winding, the positioning of the stator after winding, and the fixing of the same, and is excellent in working properties. A toroidal core type actuator having a stator and a rotor is provided, the stator having winding applied to a hollow cylindrical core composed of soft magnetic material, the rotor including a permanent magnet having north poles and south poles alternately arranged in total of m along the circumferential direction thereof, the rotor being rotatably arranged in the core of the stator via a minute air gap, wherein m of phase separators composed of non-magnetic material are arranged on the peripheral surface of the hollow cylindrical core so as to be separated from each other by 360°/m and the winding is applied to winding regions separated from each other by the phase separators.
    Type: Grant
    Filed: December 9, 1999
    Date of Patent: May 22, 2001
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Takashi Ishii, Naoyuki Harada
  • Patent number: 6229239
    Abstract: A double excitation, rotating electrical machine mounted on a shaft includes a rotor whereof the magnetic circuit carries at least one excitation element and a stator whereof the magnetic circuit carries a stator coil. The at least one excitation element includes at least a ring-shaped magnet associated with at least two disks each provided with radial teeth evenly distributed at their periphery and at least a ring-shaped part provided with slots in each of which is engaged contactless, one tooth of at least one toothed disk, and the stator magnetic circuit includes an even number, not less than two, of ring-shaped elements of magnetic circuit, at least an excitation stator coil being arranged between at least two neighboring elements among the magnetic circuit elements.
    Type: Grant
    Filed: February 23, 2000
    Date of Patent: May 8, 2001
    Assignee: Centre National de la Recherche Scientifique (C.N.R.S)
    Inventors: Jean Lucidarme, Abdelhamid Ben Ahmed, Mohamed Gabsi, Bernard Multon, Eduardo Santander, Emmanuel Hoang, Michel Lecrivain
  • Patent number: 6215207
    Abstract: A torque motor comprises a rotor having a pair of permanent magnet groups, and a pair of stator cores. Each magnet group includes a plurality of plate or rod-shaped permanent magnets arranged in a circumferential direction. The magnet groups are arranged asymmetrically with respect to a rotary axis of the rotor. That is, one magnet group is displaced one-half angle of the pitch angle of each permanent magnet from the symmetric position of the other magnet group with respect to the rotary axis of the rotor. Alternatively, the stator cores are arranged asymmetrically with respect to the rotary axis of the rotor so that a front end of one stator core is displaced from the symmetric position of a front end of the other stator core in the circumferential direction. A cylindrical magnetic cover is fitted on the rotor to cover the permanent magnets circumferentially.
    Type: Grant
    Filed: August 21, 1998
    Date of Patent: April 10, 2001
    Assignee: Denso Corporation
    Inventors: Jiro Kondo, Tomokazu Kondo, Yuichiro Miura, Hideki Kawamura
  • Patent number: 6211593
    Abstract: A synchronous motor comprising permanent magnets (35, 41) with N poles arranged at ends of N magnetic poles of a rotor, permanent magnets (38, 34) with S poles arranged at ends of S magnetic poles of the rotor, magnetic pole portions (40) made of soft magnetic member at middle portion of the N magnetic poles of the rotor, and magnetic pole portions (39) made of soft magnetic member at middle portion of the S magnetic poles of the rotor. The synchronous motor has a structure in which the respective N and S magnetic poles are shifted in the rotor rotation direction relatively by NN/NR of a stator slot pitch, wherein NN and NR are integers equal to or less than the number of poles formed in the rotor.
    Type: Grant
    Filed: October 22, 1999
    Date of Patent: April 3, 2001
    Assignee: Okuma Corporation
    Inventor: Masayuki Nashiki
  • Patent number: 6191517
    Abstract: A brushless synchronous electrical machine includes a rotor rotating about a rotor axis, and a stator that includes at least one set of magnetically active stator cores projecting radially outward from the axis, and that also includes magnetically interactive crossbars on the radially outward ends of the stator cores. The rotor includes one or more magnetically active projections that sweep past the radially inward facing surfaces of the crossbars as the rotor rotates. Preferably, there are two sets of stator cores, displaced axially and staggered azimuthally with respect to each other. Stator windings are wound toroidally about the stator cores. The rotor is provided with a magnetic field, preferably by electrical current in one or more axial windings wound toroidally with respect to the rotor axis.
    Type: Grant
    Filed: May 10, 1999
    Date of Patent: February 20, 2001
    Assignee: S. H. R. Limited BVI
    Inventor: Alexander Radovsky
  • Patent number: 6160330
    Abstract: A three-phase stepping motor comprising: a rotation shaft rotatably supported by a pair of bearings provided in predetermined places of a housing so as to be in opposition to each other; a permanent-magnet rotor formed in a cylindrical shape so as to have south (S) and north (N) poles magnetized alternately in the direction of rotation on an outer circumferential portion of the rotor, or an induced magnetization rotor having S and N poles disposed alternately in the direction of rotation which are formed in a manner so that permanent magnets with the same polarity are fitted or formed so as to be identical in polarity at their surfaces in grooves formed parallelly to each other at a regular pitch in a surface of a magnetic body formed to be cylindrical in parallel to the rotation shaft and the cylindrical magnetic body is subjected to induced magnetization to form the S and N poles alternately in the surface of the cylindrical magnetic body; and a stator disposed so as to be in opposition to a surface of one
    Type: Grant
    Filed: November 10, 1998
    Date of Patent: December 12, 2000
    Assignee: Japan Servo Co., LTD
    Inventor: Masafumi Sakamoto
  • Patent number: 6153959
    Abstract: Electric rotating machines and/or assembly which, dependent upon the specific embodiments utilized may be in the form of a motor, generator or combination of both wherein a common stator assembly is disposed in an operative position relative to at least one but in some embodiments a plurality of rotor assemblies preferably having annular configuration and further being defined by a central opening in which the stator assembly is mounted. The supporting structure has the stator assembly fixedly attached thereto as well as the one or more rotor assemblies moveably mounted thereon in rotational travel relative to the stator assembly and, dependent upon the embodiments, relative to one another when a plurality of rotor assemblies are utilized. One feature of the overall structure is an increase in versatility and applicability for specific practical application by eliminating the use, need or requirement of a central support shaft commonly found in prior motors/generators.
    Type: Grant
    Filed: July 16, 1999
    Date of Patent: November 28, 2000
    Inventor: Raul A. Lorenzo
  • Patent number: 6140729
    Abstract: An electrical machine comprises a four-pole stator 2 provided with a field winding 10 and an armature winding 11, each of the windings 10, 11 being split into two coils 22, 23 or 24, 25 closely coupled and wound so that diametrically opposite portions of both coils are disposed within diametrically opposite stator slots. A two-pole rotor (not shown) without windings is rotatable within the stator 2, and a circuit is provided for energising the armature coils 24 and 25 when direct current is supplied to terminals 26 and 27 of the circuit. Switches 28 and 29 in series with the coils 24 and 25 are switched alternately to effect alternate energisation of the coils 24 and 25 so as to generate, as a result of the opposite winding of the coils, magnetomotive forces in opposite directions.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: October 31, 2000
    Assignee: University of Warwick
    Inventors: Charles Pollock, John David Wale, Mike Barnes
  • Patent number: 6137204
    Abstract: In a VR-type resolver which is used in combination with a motor to detect the rotation position of the motor, the teeth number of a rotor of the resolver is reduced over the teeth number of a rotor of the motor. Also, the shape of the teeth of the resolver rotor is simplified into a curved shape such as a sine wave shape. Further, in another type of VR-type resolver, the number of the magnetic poles of the stator with respect to the number of the teeth of the rotor is set as a number being capable of satisfying not only the condition that it is a multiple of the phase number N and an even number but also the condition that it is a number which can be calculated according to one of the following expressions (1) and (2), that is,stator pole number=rotor teeth number/(M+1/N) (1)stator pole number=rotor teeth number/{M+(N-1)/N} (2),where M is an integral number of one of 1, 2, and 3.
    Type: Grant
    Filed: May 24, 1999
    Date of Patent: October 24, 2000
    Assignee: NSK Ltd.
    Inventor: Masaki Kuwahara
  • Patent number: 6121706
    Abstract: A reluctance motor is provided that reduces leaking magnetic flux. To generate magnetic flux between adjacent magnetic poles in a rotor 2, permanent magnets 4 are disposed in approximate centers of split magnetic paths near a borderline area between two magnetic poles in an internal portion of the rotor. Further, each of slots 8 in a stator 1 is wound with a coil of a corresponding phase such that the vector phase and amplitude expressed by the products of the number of coil turns and the amount of passing current, namely, ampere-turns, become almost identical for each of the slots. By reducing leaking magnetic flux according to this arrangement, generated torque can be increased. As the rotor mechanical strength is enhanced, the rotor can be safely driven at a higher speed. A practical motor is obtained that simultaneously achieves improved motor characteristics and reduced torque ripples.
    Type: Grant
    Filed: July 19, 1999
    Date of Patent: September 19, 2000
    Assignee: Okuma Corporation
    Inventors: Masayuki Nashiki, Takanori Yokochi
  • Patent number: 6087752
    Abstract: A motor having permanent magnets received therein includes a rotor having a plurality of circular sheet irons deposited in turn, a plurality pairs of magnet receiving slots formed through the deposited sheet irons at a predetermined angle toward the outer surface of the rotor, and permanent magnets of different polarities received into the magnet receiving slots, wherein a magnetic flux leakage preventive groove having a predetermined width and depth is formed at the outer surface of the rotor at the center between the pair of magnet receiving slots.
    Type: Grant
    Filed: March 19, 1999
    Date of Patent: July 11, 2000
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Gyeong-don Kim, Tae duk Kim
  • Patent number: 6078122
    Abstract: A reluctance machine including a plurality of phase windings where each phase winding comprises a plurality of fractional-pitched coils. The reluctance machine may be coupled to a drive that can energize one, two or more of the phase windings to provide output torque that is derived from: (i) the self-inductances of the phase windings; (ii) a combination of the self-inductances of the phase windings and the mutual inductances between the phase windings; or (iii) the mutual inductances between the phase windings.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: June 20, 2000
    Assignee: Emerson Electric Co.
    Inventors: Yifan Tang, Yue Li
  • Patent number: 6075302
    Abstract: A multiple phase heteropolar inductor electrical machine utilizing relatively movable stators and rotors wherein the rotors include electrical winding for producing electricity. The stators and rotors are spaced as to produce an electrical balancing among the machine phases. Preferably, a balance is achieved in the energy conversion process as measured over any given one-half electrical cycle within that phase. The machine substantially achieves equal and balanced peak torque per amp performance within a half cycle of operation of any given phase through the spacing between the stator and elements.
    Type: Grant
    Filed: October 20, 1997
    Date of Patent: June 13, 2000
    Inventor: Patrick J. McCleer
  • Patent number: 6064134
    Abstract: A rotor assembly for a synchronous reluctance machine has a plurality of steel punched star-shaped supports secured along a shaft at spaced locations for retaining a plurality of laminated rotor sections. The star-shaped supports have four equiangularly spaced arms having arcuate valleys disposed therebetween that define a plurality of channels for receiving the rotor sections. The rotor sections are secured to the star-shaped core by a plurality of bands fastened circumferentially around the rotor. A plurality of grooves disposed circumferentially around the rotor receive and retain the bands in place. A rotor bar and arcuate spring may be disposed within a concave cavity defined by the rotor sections to reduce audible noise produced as the rotor rotates at a high rate of speed and provide added compression on the rotor sections to the core. The rotor sections also include a dimpled separator of predetermined thickness disposed between the laminate sheets to optimize the machine.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: May 16, 2000
    Assignee: General Motors Corporation
    Inventors: Ahmed Mostafa El-Antably, Moshen M. Erfanfar, Ronald Allen Martin
  • Patent number: 6051903
    Abstract: A switched reluctance motor driven by a two-phase source, includes a stator having an even number of evenly-spaced, like stator poles defining a gap between each stator pole; windings for each of the two phases of the motor wound about stator poles that are circumferentially separated by a winding and an associated stator pole of a different phase; and a rotor mounted for rotation relative to the stator, the rotor having an even number of rotor poles, the rotor poles being dimensioned such that when the phases are alternately energized, the rotor poles operatively interact with the stator poles such that the motor advances sequentially to a first state wherein one-third of the rotor poles are magnetically coupled to a like number of the stator poles, to a second state wherein two-thirds of the rotor poles are magnetically coupled to a like number of stator poles and to a third state wherein all of the rotor poles are magnetically coupled to a like number of stator poles.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: April 18, 2000
    Assignee: Tridelta Industries, Inc.
    Inventor: Wayne A. Pengov
  • Patent number: 6049153
    Abstract: A motor comprises a stator core having plural teeth and slots provided among the teeth, a winding applied on the teeth by a turn, and a rotor incorporating plural permanent magnets. The rotor is rotated and driven by utilizing reluctance torque in addition to magnetic torque. Since the winding is not crossed, the size of the coil end is reduced.
    Type: Grant
    Filed: February 2, 1998
    Date of Patent: April 11, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Noriyoshi Nishiyama, Tomokazu Nakamura, Yasufumi Ikkai, Yukio Honda, Hiroshi Murakami, Shinichiro Kawano
  • Patent number: 6046522
    Abstract: An anti-reverse rotation device suitable for use with a single phase synchronous motor and the like, has a housing with an inner cavity, a rotatable member in the form of a disk and at least one blocking member. The cavity of the housing is bounded by an inner wall forming a cam surface with at least one abrupt change forming a blocking surface. The blocking member is accommodated within a recess formed in the periphery of the disk and moves along the cam surface as the disk rotates. In the forward direction, the cam surface urges the blocking member into the recess. In the reverse direction, the blocking member becomes jammed between the disk and the blocking surface preventing further rotation in the reverse direction.
    Type: Grant
    Filed: October 29, 1998
    Date of Patent: April 4, 2000
    Assignee: Johnson Electric S.A.
    Inventor: Fretrick Siu Kwan Ko
  • Patent number: 6046568
    Abstract: A switched reluctance machine includes a first element having a plurality of uniform poles and a second element having a first pole and a second pole. The first pole has a wide face and the second pole has a narrow pole face. The first and second elements are disposed for movement relative to each other such that the wide and narrow poles are moveable in spaced relation to the plurality of uniform poles.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: April 4, 2000
    Assignee: Tridelta Industries, Inc.
    Inventor: Wayne A. Pengov
  • Patent number: 6020712
    Abstract: An AC machine comprises: a motor energized by an AC source subject to irregularities of frequency and voltage; a generator driven by the motor for supplying an AC output signal of substantially constant frequency and voltage, the generator having a rotor with a layer of a re-magnetizable, relatively high coercive magnetic material on the rotor and a stator of a soft magnetic material having a pole piece and an excitation coil on the pole piece, the stator and the rotor rotating relative to one another with a clearance enabling rotor poles to be formed on the re-magnetizable layer by current energizing the excitation coil; and, a control signal generator responsive to at least one of the AC output signal and a signal representative of the current energizing the excitation coil for generating pulses of programmed wave shapes which differ in at least one of width, phase and magnitude as necessary to modify the rotor poles during the irregularities of the AC source to maintain the substantially constant frequency
    Type: Grant
    Filed: February 23, 1998
    Date of Patent: February 1, 2000
    Assignee: Precise Power Corporation
    Inventors: John F. Roesel, Jr., Ronnie J. Barber
  • Patent number: 6008559
    Abstract: In a motor having a permanent magnet built in a rotor, a hole for preventing a short-circuit of magnetic flux is disposed so that the hole is adjacent to the outer rim of rotor core, and adjoins to a slit for receiving a permanent magnet as well as the permanent magnet per se. This structure prevents a short-circuit of magnetic flux generated by both ends of the permanent magnet, and the magnetic flux at both ends of the magnet can flow to a stator, thereby contributing to generate torque effectively. As a result, the highly efficient motor with less cogging torque, less vibration and lower noise can be provided.
    Type: Grant
    Filed: July 22, 1998
    Date of Patent: December 28, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshinari Asano, Masayuki Shinto, Hiroshi Ito, Takeshi Morishige, Yukio Honda, Hiroshi Murakami, Naoyuki Kadoya, Shizuka Yokote
  • Patent number: 5990591
    Abstract: A permanent magnet type synchronous motor includes an iron core rotor having a plurality of holes which are circumferentially spaced, permanent magnets mounted in the holes, an iron core stator and coils arranged in the stator iron core. The permanent magnets are defined by a flat surface extending tangentially of the rotor, tapered surfaces formed at both ends of the flat surface and extending obliquely outward in a direction approaching each other, and an arcuate surface joining the two tapered surfaces. Each permanent magnet is supported by tapered surfaces formed at opposing ends of the holes and extending obliquely and radially outward in a direction approaching each other. When the rotor is rotated, the centrifugal force is received at the tapered surfaces of the holes, rather than at their arcuate portion.
    Type: Grant
    Filed: February 20, 1998
    Date of Patent: November 23, 1999
    Assignee: Aisin Aw Co., Ltd.
    Inventors: Yasuo Yamaguchi, Masahiro Hasebe, Satoru Wakuta
  • Patent number: 5969444
    Abstract: A stepping motor is equipped with a rotor, a supporting member that rotatably support the rotor, and stators that have multiple stator teeth and that face each other across the diameter of the rotor, wherein said multiple stator teeth are positioned such that they are apart from each other. Using the construction described above, it is possible to make the rotor diameter smaller than the conventional model, thereby reducing the overall size of the stepping motor. Therefore, it is possible to make the outer diameter of lens barrel smaller than the conventional model without changing the lens diameter, which in turn makes the overall size of the camera more compact.
    Type: Grant
    Filed: April 28, 1998
    Date of Patent: October 19, 1999
    Assignee: Minolta Co., Ltd.
    Inventor: Masatoshi Kamitani
  • Patent number: 5966988
    Abstract: A shaft rotation driving apparatus for a machine tool having a main spindle for rotating a tool or a workpiece, comprises: a magnetic anisotropic rotor formed integral with the main spindle itself or with a rotary sleeve itself fitted to the main spindle; a stator disposed coaxially along an outer circumference of the magnetic anisotropic rotor; a field winding wound around the stator, for magnetizing the rotor in a predetermined direction; and an armature winding wound around the stator, for providing a rotative force to the rotor.
    Type: Grant
    Filed: February 26, 1998
    Date of Patent: October 19, 1999
    Assignee: Toshiba Kikai Kabushiki Kaisha
    Inventors: Katsuyosi Aiso, Sakasi Adati, Tosihiro Igarasi, Sin Tanoue, Satosi Kumamoto, Masanori Wakuda
  • Patent number: 5969454
    Abstract: A switched reluctance motor, comprising:a stator formed from a magnetically permeable material, having "n" number of evenly spaced, radially oriented, like stator poles, the stator poles having like stator pole faces and forming a uniform gap between adjacent stator poles;windings for two phases wound about stator poles that are circumferentially separated by a winding and an associated stator pole of a different phase;a rotor mounted for rotation relative to the stator about an axis, the rotor having at least two rotor sections, a first of the at least two rotor sections including at least 1/4 "n" number of like, wide rotor poles, each having a like, wide rotor pole face, and a second of the at least two rotor sections including at least 1/4 "n" number of like, narrow rotor poles, each having a like, narrow rotor pole face, the rotor having:a first angular position wherein a first portion of the wide rotor pole faces of the first rotor section are in alignment with a first pair of opposite, energized stator
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: October 19, 1999
    Assignee: Tridelta Industries, Inc.
    Inventors: Wayne A. Pengov, Mark Kusner
  • Patent number: 5962947
    Abstract: To reduce as much as possible the motor vibration due to the effect of harmonic components contained in the induced electromotive force waveform induced in the armature coil. In a motor structure, the pole tooth shapes of one pole tooth and the corresponding pole tooth thereto constituting one phase are made different from each other by changing their areas or amounts of skew, whereby the third harmonics caused by variations in the magnetic fluxes interlinking with these pole teeth are caused to cancel each other. Thus, the rotational vibration which has hitherto been a problem can be reduced and, further, the accuracy of the rotor movement can be improved without lowering the dynamic torque characteristic of the motor.
    Type: Grant
    Filed: August 13, 1997
    Date of Patent: October 5, 1999
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Haruyoshi Hino, Sakae Fujitani, Naomi Inoue, Hideki Sakiyama
  • Patent number: 5962944
    Abstract: In a permanent magnet rotor type electric motor having a stator core generating a rotation magnetic field and provided therein with a rotor core in which each magnetic pole is formed by a permanent magnet, the rotor core is fabricated by coaxially and unitedly joining a first core member and a second core member, in which a first permanent magnet of a predetermined cross-section shape is embedded per magnetic pole in the first core member, and a second permanent magnet which is made of a different material and has a different cross-section shape from those of the first permanent magnet is embedded per magnetic pole in the second core member, thereby achieving the permanent magnet rotor type electric motor having the performance and size appropriate for the intended use.
    Type: Grant
    Filed: October 20, 1998
    Date of Patent: October 5, 1999
    Assignee: Fujitsu General Limited
    Inventors: Kenji Narita, Takashi Suzuki, Hiroyuki Okudera, Yuji Kawai, Yuji Souma, Koji Kawanishi, Yoshichika Fukuda
  • Patent number: 5955807
    Abstract: A synchronous electric machine includes a stator having an armature winding, a rotor having axially laminated magnetic sheets and a field coil, a plurality of permanent magnets disposed in the rotor to form N-pole and S-pole on the outer circumference of the rotor, and ribs and pins magnetically bypassing the N-poles and S-poles of the permanent magnets. The pins also attach the laminated magnetic sheets together as a unit. The rotor has a plurality of axially extending holes on its circumference for accommodating permanent magnets.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: September 21, 1999
    Assignee: Denso Corporation
    Inventors: Hiroaki Kajiura, Keiichiro Banzai, Sumio Yanase, Akira Fukushima
  • Patent number: 5952758
    Abstract: A rotating electrical machine including a rotor (2), the magnetic circuit of which carries excitation members, and a stator (16), the magnetic circuit of which carries a stator coil. The magnetic circuit of the rotor includes a shaft (1) on which are mounted end flanges (3) and at least one toothed disk (4) disposed between the end flanges, the teeth of the toothed disk being regularly spaced at its periphery, and at least one annular member (9) mounted on the end flanges and having slots (10) regularly distributed at its periphery and in each of which is engaged one tooth of at least one toothed disk. The end flanges and the toothed disk are spaced apart by gaps in which excitation members (14, 15) are accommodated.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: September 14, 1999
    Assignee: Centre National de la Recherche Scientifique (C.N.R.S.)
    Inventors: Jean Lucidarme, Abdelhamid Ben Ahmed, Mohamed Gabsi, Bernard Multon, Eduardo Santander, Emmanuel Hoang
  • Patent number: 5936325
    Abstract: A synchronous electrical machine comprising a rotor and a stator, each having a plurality of notches, wherein the rotor is a stack of laminations without conductor windings and without permanent magnets, and wherein the stator has magnetizing means defining at least one pair of poles thereon, while the notches of said stator receive at least one secondary winding.
    Type: Grant
    Filed: December 29, 1997
    Date of Patent: August 10, 1999
    Assignee: Valeo Electronique
    Inventor: Alfred Permuy
  • Patent number: 5929547
    Abstract: A rotor for use in an electrical mechanism comprises a core in which there are formed first slots extending in a direction substantially perpendicular to a radius of the core. A plurality of second slots is formed in the core, the second slots extending from respective ends of the first slots, whereby there is provided a plurality of pairs of adjacently disposed second slots. The second slots of each pair extend from different first slots and converge toward one another in a direction toward an outer periphery of the core. Permanent magnets are disposed in the first and second slots.
    Type: Grant
    Filed: May 13, 1998
    Date of Patent: July 27, 1999
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Tae-duk Kim
  • Patent number: 5929551
    Abstract: A rotor assembly for a synchronous reluctance machine has a plurality of steel punched star-shaped supports secured along a shaft at spaced locations for retaining a plurality of laminated rotor sections. The star-shaped supports have four equiangularly spaced arms having arcuate valleys disposed therebetween that define a plurality of channels for receiving the rotor sections. The rotor sections have a plurality of linearly-disposed apertures for receiving mounting members that extend radially from the valleys of the star-shaped supports. The portions of free ends of the mounting members that extend through the apertures, are stamped or formed to secure the rotor sections to the star-shaped supports. A rotor bar may be disposed within a concave cavity defined by the rotor sections to reduce audible noise produced as the rotor rotates at a high rate of speed.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: July 27, 1999
    Assignee: General Motors Corporation
    Inventors: Ahmed Mostafa El-Antably, Moshen M. Erfanfar
  • Patent number: 5903069
    Abstract: A synchronous reciprocating electric machine includes a first magnet system having first and second opposing surfaces forming between them a gap, and a second magnet system mounted within the gap so as to be displaceable relative to the first magnet system along a line of travel through the gap. The the first magnet system is configured for generating a magnetic field, referred to as the "gap field", directed across the gap primarily perpendicular to the first surface. The second magnet system includes two magnetic elements configured to generate equal but opposite magnetic fields primarily perpendicular to the first surface. These magnetic elements are spaced from each other along the line of travel by a distance b, where b>0. One of magnet systems produces a non-alternating magnetic field and the other is a coil assembly for producing an operating magnetic field.
    Type: Grant
    Filed: September 19, 1997
    Date of Patent: May 11, 1999
    Assignee: Medis El, Ltd.
    Inventor: Misha Hiterer
  • Patent number: 5903080
    Abstract: A reluctance type synchronous motor comprises: a stator with a plurality of slots placed at an even pitch angle wherein stored inside each slot is a stator winding for creating stator magnetic poles with a predetermined phase alternating current being supplied thereto. A rotor sustained by a shaft and changing magnetic reluctance in its circumferential direction by inclusion inside of a plurality of magnetic isolating portions creates desired magnetic poles. At least one of the central angles between magnetic poles created at the rotor is shifted from the other central angles so that torque ripples during rotation can be reduced.
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: May 11, 1999
    Assignee: Okuma Corporation
    Inventors: Masayuki Nashiki, Akiyoshi Satake