Inductor-type Generators (variable Reluctance) Patents (Class 310/168)
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Patent number: 7646126Abstract: A permanent-magnet switched-flux (PMSF) device has a ferromagnetic outer stator mounted to a shaft about a central axis extending axially through the PMSF device. Pluralities of top and bottom stator poles are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the ferromagnetic outer stator. A ferromagnetic inner rotor is coupled to the shaft and has i) a rotor core having a core axis co-axial with the central axis; and ii) first and second discs having respective outer edges with first and second pluralities of permanent magnets (PMs) mounted in first and second circles, radially outwardly from the rotor core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.Type: GrantFiled: June 9, 2008Date of Patent: January 12, 2010Assignee: Board of Regents of the Nevada System of Higher Education on Behalf of the University of Nevada, RenoInventors: Andrzej M. Trzynadlowski, Ling Qin
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Patent number: 7646194Abstract: A resolver of a variable reluctance type includes a resolver stator portion of a substantially annular shape centered about a central axis, and a resolver rotor portion which is attached to a shaft of a motor rotor portion arranged inwardly of the resolver stator portion. The resolver is operable to increase accuracy for detecting a rotational angle when a size of gap g between a rotor core and a resolver stator portion at a predetermined point at an outer circumferential edge of the rotor core is set by using a maximum value for the gap g (gmax), a minimum value for the gap g (gmin), angle ? defined by a predetermined point and a reference point, axial double angle n, and the coefficient.Type: GrantFiled: September 26, 2007Date of Patent: January 12, 2010Assignee: Nidec CorporationInventor: Yusuke Makino
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Patent number: 7638916Abstract: A secondary part of an electric machine has a toothed profile, with at least one tooth being unlaminated. The at least one tooth is made of at least two materials, wherein the at least one tooth forms a cavity which is filled with an iron-containing material representing one of the two materials.Type: GrantFiled: March 21, 2007Date of Patent: December 29, 2009Assignee: Siemens AktiengesellschaftInventors: Thomas Hoppe, Zeljko Jajtic, Gerhard Matscheko, Christian Volmert
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Patent number: 7628518Abstract: A bicycle hub includes a hub shaft, a hub shell, a bearing arrangement, an electricity generating mechanism and at least one lamp. The hub shaft is configured and arranged to be mounted in a non-rotatable manner to a bicycle frame. The hub shell has a hollow interior with the hub shaft being disposed in the hollow interior of the hub shell. The bearing arrangement is arranged between the hub shell and the hub shaft in such a manner that the hub shell can rotate freely with respect to the hub shaft. The electricity generating mechanism is arranged inside the hub shell and is configured to generate electricity in response to relative rotation of the hub shell with respect to the hub shaft. The lamp is arranged on at least one end of the hub shell and illuminated using electricity generated by the electricity generating mechanism.Type: GrantFiled: March 5, 2004Date of Patent: December 8, 2009Assignee: Shimano Inc.Inventors: Kazuhiro Fujii, Koji Uno
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Patent number: 7605500Abstract: A miniature generator includes a carrier having a tubular shaft on the inside, a substantially C-shaped permanent magnet mounted on the tubular shaft inside the carrier, a match mounted on the tubular shaft inside the carrier and joined to the permanent magnet to keep the permanent magnet in a slightly unbalanced condition for allowing rotation of the permanent magnet upon movement of the carrier by an external force, and a winding holder sleeved onto the carrier and having wound thereon multiple windings for inducing an induction current upon rotation of the permanent magnet in the carrier.Type: GrantFiled: August 15, 2007Date of Patent: October 20, 2009Inventors: Chin-Lung Liao, Yi-Chih Chen
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Patent number: 7605515Abstract: A monophase transverse circuit has two rows of cylindrical air gaps which are provided with conductors between terminal pairs, the terminal pairs are rotated at a quarter turn in order, a coil in the form of a flat double U-shaped arch remains global having consequent terminals by defining meanders between terminals which are laterally introducing opposite to a meander and whose sheets are now progressively attacked on one row of cylindrical or flat air gaps, thereby balancing axial forces, axial and opposite currents between adjacent slots convert a preceding ring-shaped flux into radial fluxes in the terminals by acting upon the rotor terminals with the same pitch and polarized by induction.Type: GrantFiled: May 4, 2005Date of Patent: October 20, 2009Inventor: Gerard Koehler
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Patent number: 7605512Abstract: A method of designing a reluctance resolver, and the resolver comprises a stator and a rotor, and an exciting coil and two sets of outputting wires wind around the tooth portion of the stator. The designing method comprises the following steps: fixing relative position; calculating the turn ratio of the stator; winding the coil of the stator; and designing the resolver. And the resultant resolver can improve the precision of calculating the position of the motor rotor.Type: GrantFiled: June 17, 2007Date of Patent: October 20, 2009Assignee: Hiwin Mikrosystem Corp.Inventor: Chia-Ming Chang
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Patent number: 7579734Abstract: A TPSRM may include a stator, having a plurality of poles and a ferromagnetic or iron back material, and a rotor having a plurality of poles and a ferromagnetic or iron back material. A current flowing through coils wound around a first set of the plurality of stator poles induces a flux flow through the first set of stator poles and portions of the stator back material during a first excitation phase. A current flowing through coils wound around a second set of the plurality of stator poles induces a flux flow through the second set of stator poles and portions of the stator back material during a second excitation phase. The numbers of stator and rotor poles for this TPSRM are selected such that substantially no flux reversal occurs in any part of the stator back material as a result of transitioning between the first and second excitation phases.Type: GrantFiled: March 17, 2004Date of Patent: August 25, 2009Assignee: Panaphase Technologies, LLCInventors: Krishnan Ramu, Savio Nimal Lobo
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Publication number: 20090195113Abstract: A stator for an alternating-current induction machine, the stator comprising a cylindrical stator core. The stator may also comprise a first stator tooth. The first stator tooth may comprise a proximal end extending from the cylindrical stator core and a distal end comprising an outer surface positioned to face a rotor. A first arc of the outer surface may be eccentric relative to the cylindrical stator core. Various additional stator designs and methods are also disclosed.Type: ApplicationFiled: January 15, 2008Publication date: August 6, 2009Applicant: Raser TechnologiesInventors: Sergei Kolomeitsev, Omun Kwon
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Patent number: 7569964Abstract: The variable reluctance type angle detector has a stator and a rotor. The rotor is provided rotatably with respect to the stator. The stator has a plurality of tooth members disposed in a circle. An excitation wire and an output wire are wound around the tooth members. The rotor has such a shape that a gap permeance with respect to the stator varies in a sine wave fashion with respect to an angle ?. The stator is provided with an end insulator for insulating and covering the tooth members. The end insulator is provided with partitions each insulating and separating the excitation wire from the output wire wound around each of the tooth members in a radial direction of the stator.Type: GrantFiled: October 10, 2006Date of Patent: August 4, 2009Inventor: Yasuo Ijima
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Patent number: 7560843Abstract: A rotating electric machine includes a stator and a rotor. The tip of a salient pole portion of the rotor is bilaterally asymmetrically provided with a cut. The effect of the cut reduces torque ripple during a regenerative running mode. The regenerative running mode is not performed during low speed running but is often performed during high speed running and the driver is more sensitive to in the regenerative running mode noise than in a power running mode. As for the regenerative running mode, measures against torque ripple are taken based on the structure of the rotating electric machine. Preferably, as for the power running mode which bothers the driver about noise during very low speed running, a controller allows a compensation current to be fed to take measures against torque ripple. A compact and high power vehicle drive system with torque ripple reduced and a vehicle incorporating the vehicle drive system can be provided.Type: GrantFiled: November 14, 2005Date of Patent: July 14, 2009Assignee: Toyota Jidosha Kabushiki KaishaInventor: Munehiro Kamiya
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Patent number: 7541761Abstract: An apparatus and a method of manufacture of a DC electric motor operable over a range of voltage by virtue of a DC-DC regulator having an inductance provided by one or more windings on the stator of the motor. A conductor is wound about an interpole of the stator and coupled, as an inductance, to a voltage regulator circuit, allowing operation of the DC motor over a substantial range of input voltage.Type: GrantFiled: July 31, 2006Date of Patent: June 2, 2009Assignee: Comair Rotron IncInventor: Fred A. Brown
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Patent number: 7521826Abstract: A method of assembling a power tool, a power tool, a method of assembling an electrical device, and an electrical device includes a switched reluctance motor. The electrical device is preferably a hand-held power tool, however, any type of electrical device that includes a switched reluctance motor may benefit from any number of aspects of the invention. In one independent aspect, the invention provides a construction that reduces tolerance stack-up. In another independent aspect, the invention provides a self-contained electronics package that plugs into a switched reluctance motor to provide control operation of the switched reluctance motor. In another independent aspect, the invention provides enhanced cooling that increases the efficiency of the electrical device using a switched reluctance motor. In another independent aspect, the invention provides an encapsulated magnet that allows for contaminant free motor control over the life of the SR motor.Type: GrantFiled: January 13, 2006Date of Patent: April 21, 2009Assignee: Milwaukee Electric Tool CorporationInventors: David A. Hempe, Gary D. Meyer, Roderick N. Ebben, Jeffrey M. Brozek
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Publication number: 20090045768Abstract: An improved single-switch control circuit for use in a multi-phase switched reluctance machine is provided. The control circuit includes at least first and second phase windings, a switch, a capacitor, and a diode. The capacitor may have a polarity opposite that of a power source in the control circuit. The first winding may be connected in series with the switch and connected in parallel with a circuit block comprising the second winding. The second winding may be connected in parallel with the capacitor and in series with the diode. In operation, the switch may be used to redirect current from the first winding to the second winding. The capacitor can become charged by the redirected current until it eventually stores enough energy to essentially discontinue current flow in the first winding. Then, the capacitor can discharge its stored energy as a current through the second winding. In this manner, substantially all of the energy from the first winding can be transferred to the second winding.Type: ApplicationFiled: December 5, 2007Publication date: February 19, 2009Inventor: Krishnan Ramu
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Patent number: 7489060Abstract: A machine includes a shaft adapted to rotate about a longitudinal axis and formed of a magnetic material and a rotor assembly rotationally engaged with the shaft The rotor assembly includes a pair of rotor disks comprising a magnetic material, each of the rotor disks having a number of magnetic poles, the magnetic poles being spaced apart circumferentially. The rotor disks are coupled to the shaft for rotation about the shaft and generation of a rotating permeance wave. The machine further includes a stator assembly that includes a magnetic core stator disposed between the rotor disks, a number of armature windings supported on the magnetic core stator, and a stationary superconducting field coil disposed between the magnetic core stator and the shaft. The stationary superconducting field coil is configured as a stationary magneto-motive force (MMF) source for the rotating permeance wave produced by the rotor assembly to produce a rotating magnetic field.Type: GrantFiled: June 30, 2006Date of Patent: February 10, 2009Assignee: General Electric CompanyInventors: Ronghai Qu, James William Bray
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Patent number: 7482718Abstract: Enhanced internal electrical generators are provided which include pole pieces that form air gaps flanked with conductive wire coils. Rotatable armatures supporting permanent magnets are arranged to swing or revolve relative to the air gaps such that the magnetic flux thereof is intersected by the wire coils to generate electrical voltage and current therein. These generators may be incorporated within the housing of many portable devices such as cell phones to self generate electrical current useful for operating the device or recharging its batteries or other component that stores the generated electrical energy.Type: GrantFiled: August 8, 2005Date of Patent: January 27, 2009Assignee: Incelex, LLCInventors: Berj A. Terzian, Jack A. Ekchian
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Patent number: 7467456Abstract: A method of arranging a resolver comprises the steps of: a, setting stator magnetic poles number of the resolver Ns as a number being in integral multiples (t) of a phase number q; b, figuring out rotor magnetic pole number Nr based on a formula; c, arranging the stator and the rotor based on the stator magnetic poles number of the resolver Ns and the rotor magnetic pole number Nr, and producing signals with phase differences.Type: GrantFiled: March 2, 2006Date of Patent: December 23, 2008Assignee: Hiwin Mikrosystem Corp.Inventors: Chia-Ming Chang, Chih-Yu Wang, Lieh-Feng Huang
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Patent number: 7459822Abstract: An electric machine, such as a switched reluctance motor (SRM), having one or more transverse flux axes is described. The rotor and stator of the electric machine have more than one phase, not necessarily of even number. Flux guidance regions within the stator are angularly and spatially located such that they may be transverse, or not coinciding with, the plane perpendicular to the axis of shaft rotation. The flux guidance regions are composed so as to contain a magnetic field whose flux is guided in either a loop or coupled configuration. In the loop configuration, multiple flux guidance paths that are able to operate simultaneously exist within each chuck arrangement. In the coupled configuration, a single primary flux guidance path exists within the chuck arrangement. Transverse flux guidance allows for the removal and replacement of stator windings without significant disassembly or removal of the motor.Type: GrantFiled: May 13, 2005Date of Patent: December 2, 2008Inventors: Weston C. Johnson, Richard M. Currie
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Patent number: 7432704Abstract: An inductor-type resolver capable of reducing a residual voltage by providing a correction winding inside the resolver is provided. Two magnetic pole portions 11 and 15 include winding portions W11 and W12, respectively, which constitute a first signal detecting winding W1. Two magnetic pole portions 13 and 17 include winding portions W21 and W23, respectively, which constitute a second signal detecting winding W2. A remaining magnetic pole portion W19 includes a correction winding W3 for obtaining a correction voltage used for reducing the residual voltage.Type: GrantFiled: June 9, 2006Date of Patent: October 7, 2008Assignee: Sanyo Denki Co., Ltd.Inventors: Sakae Kishi, Kazuhiro Makiuchi
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Publication number: 20080238236Abstract: A switched reluctance machine is provided. The switched reluctance machine has a rotor including a rotor core, where the rotor core includes multiple laminated sheets, each of the laminated sheets including multiple ferromagnetic regions and multiple non-ferromagnetic regions formed of a single material. The ferromagnetic and the non-ferromagnetic regions are alternately arranged such that the ferromagnetic regions form multiple rotor teeth and the non-ferromagnetic regions define multiple non-ferromagnetic gaps between the rotor teeth.Type: ApplicationFiled: March 27, 2007Publication date: October 2, 2008Applicant: GENERAL ELECTRIC COMPANYInventor: Ayman Mohamed Fawzi El-Refaie
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Patent number: 7429840Abstract: An electrical machine having stator (30) and rotor (31) is disclosed. The motor has field windings (F) and armature windings (A) energized by a suitable power electronic controller (401). A controller (400) sends signals to the power electronic controller (401) to control the armature current to control operation of the machine. When the machine is operating as a motor, the armature windings (A) will be supplied with electrical current from the power electronic controller by the application of applied voltage in synchronism with the rotation of the rotor (31). A mutually induced first electrical signal dependent on rotational position of the rotor will be induced within the field windings (F). This will create a superimposed gradient in the field current delivered by the power electronic controller (401).Type: GrantFiled: September 12, 2003Date of Patent: September 30, 2008Assignees: Black & Decker Inc., University of LeicesterInventors: Charles Pollock, Helen Geraldine Phyllis Pollock
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Patent number: 7425808Abstract: A rotor is provided with slits each of which serves as a flux barrier blocking a magnetic flux. A direction shown by an arrow is a forward direction along which the rotor rotates when a vehicle moves forward. Each of the slits has a width tapering down from a trailing position toward a leading position with respect to the forward direction. The rotation in a reverse direction opposite to the forward direction shown by the arrow causes larger magnetic flux linkage than the rotation in the forward direction, and hence generates high torque and high counterelectromotive force. Therefore, in the reverse direction, the rotor cannot serve as a motor to produce an output unless high voltage is applied thereto. Accordingly, the torque generated in the reverse direction is used for regenerative operation. It is thereby possible to provide a vehicle drive system capable of exhibiting performance in a well-balanced manner between power running and regenerative operation, and a vehicle provided with the same.Type: GrantFiled: November 14, 2005Date of Patent: September 16, 2008Assignee: Toyota Jidosha Kabushiki KaishaInventor: Munehiro Kamiya
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Publication number: 20080179982Abstract: The present invention deals with a transverse flux machine of the switched reluctance variety. The transverse flux machine consists of multiple phases where each phase is spaced axially along the shaft. Axial spacing provides many benefits including a decreased weight and a capability to use simple wound bobbin coils for the windings. An embedded cooling loop is provided within the coils themselves. This cooling loop provides internal temperature regulation for the windings and allows for a higher efficiency among other benefits.Type: ApplicationFiled: January 30, 2007Publication date: July 31, 2008Inventor: Dennis A. Kramer
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Patent number: 7385330Abstract: A permanent-magnet switched-flux (PMSF) apparatus comprises a plurality of permanent-magnet switched-flux (PMSF) devices, wherein each of the plurality of PMSF devices comprises a ferromagnetic outer rotor coupled to a shaft, wherein the ferromagnetic outer rotor comprises a plurality of permanent-magnets coupled to an inner surface of the ferromagnetic outer rotor, an inner stator rotatably disposed in the ferromagnetic outer rotor, wherein the inner stator comprises a stator core and multiple serrated edges forming multiple stator poles distal from the stator core, wherein the multiple stator poles are configured to interface with the plurality of permanent-magnets, and a coil disposed on the stator core between the multiple stator poles, wherein the coil is coupled to the plurality of permanent-magnets, wherein a magnetic flux of the plurality of permanent-magnets is operable to pass through the coil, and wherein the magnetic flux is configured to switch to an opposite direction in response to a rotation oType: GrantFiled: February 27, 2007Date of Patent: June 10, 2008Assignee: Board of Regents of the Nevada System of Higher Education on Behalf of the University of Nevada, RenoInventors: Andrzej M. Trzynadlowski, Ling Qin
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Publication number: 20080001491Abstract: A machine includes a shaft adapted to rotate about a longitudinal axis and formed of a magnetic material and a rotor assembly rotationally engaged with the shaft The rotor assembly includes a pair of rotor disks comprising a magnetic material, each of the rotor disks having a number of magnetic poles, the magnetic poles being spaced apart circumferentially. The rotor disks are coupled to the shaft for rotation about the shaft and generation of a rotating permeance wave. The machine further includes a stator assembly that includes a magnetic core stator disposed between the rotor disks, a number of armature windings supported on the magnetic core stator, and a stationary superconducting field coil disposed between the magnetic core stator and the shaft. The stationary superconducting field coil is configured as a stationary magneto-motive force (MMF) source for the rotating permeance wave produced by the rotor assembly to produce a rotating magnetic field.Type: ApplicationFiled: June 30, 2006Publication date: January 3, 2008Inventors: Ronghai Qu, James William Bray
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Publication number: 20080001495Abstract: A machine includes a stator assembly that includes a stator yoke, a pair of armature coils mechanically coupled to the stator yoke, and a stationary superconducting field coil. The stator yoke comprises a magnetic material. The machine further includes a shaft rotatably mounted in the stator yoke, the shaft comprising a non-magnetic material. The machine further includes a rotor assembly rotationally engaged with the shaft. The rotor assembly includes a rotor disk extending between the armature coils, the rotor disk having an inner portion and an outer portion. The outer portion of the rotor disk includes a number of circumferentially-spaced, magnetic poles. The rotor disk is coupled to the shaft for rotation about the shaft and generation of a rotating permeance wave.Type: ApplicationFiled: June 30, 2006Publication date: January 3, 2008Inventors: Ronghai Qu, James William Bray
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Patent number: 7312549Abstract: In order to improve the torque per weight ratio in electrical machines for a lower price it is proposed to use a segmented stator design. The segmented stator design is based on general E shaped cores traditionally used for single-phased transformers and inductors, The E-cores has a coil around the centered leg and is assembled parallel to the rotor axis, which means it will function with the transverse flux principle. A radial flux principle can also be performed with the E-cores if the E-cores are divided into two U-sections with a full pitch winding in between them. A clear extra advantage with the E-cores is short flux paths meaning less steel has to be magnetised. For a low volume production standard E-cores can be used making the investment in production facilities smaller. The E-core machines using the transverse principle can have different pole-shapes such the normal force between the rotor and stator are significantly reduced.Type: GrantFiled: May 8, 2002Date of Patent: December 25, 2007Assignee: Aalborg UniversitetInventor: Peter Omand Rasmussen
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Patent number: 7279815Abstract: A swing motor having an opening formed asymmetrically inside a stator. The swing motor is formed with an asymmetrical opening, in particular in a semicircular shape inside the stator. The opening is provided with a plurality of salient poles wound with coils. Electric current alternately flows through the coils so that a rotor, installed in the stator in a state of being spaced apart from the stator, can reciprocally move. Since the height of the stator is reduced by forming the opening asymmetrically in comparison with the case of forming the opening symmetrically, it is advantageous for minimizing the size of the product in which the swing motor is installed.Type: GrantFiled: November 2, 2004Date of Patent: October 9, 2007Assignee: LG Electronics Inc.Inventors: Jun Young Lim, Yo Han Lee, Sang Young Kim, Myung Keun Yoo, Yong Won Choi
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Patent number: 7276830Abstract: A motor (1) has a stator (2) and a rotor (10) mounted for rotation in the stator. A commutating salient pole (11) of the stator as a winding (7), and a field-producing salient pole (12) has a winding (8). The rotor has at least two salient poles (10a, b). An outer back-iron (13) magnetically joins bases of said stator poles. An inner back-iron (14) extends from the field pole around the rotor to such an extent that a substantial amount of the magnetic field in the rotor between its poles is short-circuited by the inner back-iron, at least for a part of its rotation. An electrical circuit powers the windings to drivingly rotate the rotor.Type: GrantFiled: June 11, 2002Date of Patent: October 2, 2007Inventor: Paul Lefley
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Patent number: 7250734Abstract: Certain exemplary embodiments can provide a switched reluctance machine, comprising a rotor; and a stator encircling said rotor and comprising a plurality of radially distributed stator poles, each of said stator poles comprising a set of coils, each set of coils comprising: a phase coil adapted to be switched to affect a rotation of said rotor; and a field excitation coil adapted to, while said rotor is rotating, generate a magnetic field from a received excitation current.Type: GrantFiled: May 27, 2004Date of Patent: July 31, 2007Assignee: Synchrony, Inc.Inventors: Victor Iannello, Robert Jett Field, Christopher K. Sortore
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Patent number: 7230360Abstract: A switched reluctance machine (SRM) having a rotor and stator pole numerical relationship of S number of stator poles and R number of rotor poles, where R=2S?2, when S is greater than 4; provides improved power density, torque production, torque ripple, and acoustic noise, and is readily adaptable to existing hardware such as known controllers and the like.Type: GrantFiled: November 8, 2004Date of Patent: June 12, 2007Assignee: Illinois Institute of TechnologyInventors: Piyush C. Desai, Ali Emadi
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Patent number: 7205694Abstract: A switched reluctance machine has a stator which has an array of alternate wide and narrow poles around its inner circumference. Coils are wound around the wide poles only. The rotor includes segments of soft magnetic material carried on a non-magnetic core. The segments are so proportioned at the air gap that the flux produced by one stator coil passes through two or more segments and returns through the adjacent narrow poles. The machine is capable of producing a high output.Type: GrantFiled: April 30, 2003Date of Patent: April 17, 2007Assignee: Switched Reluctance Drives LimitedInventor: Barrie Charles Mecrow
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Patent number: 7180216Abstract: A high intensity lighting system comprises a plurality of high intensity discharge lamps electrically connected to a polyphase alternator and a prime mover mechanically connected to the alternator. An inherent impedance characteristic of the alternator permits the lamps to be reliably started and energized without any separate ballast or comparable impedance element. The alternator comprises a stator having teeth extending from a backiron. The teeth consist of the alternator phases, and the coils encircle the respective teeth of each pair and are wound in opposite sense and connected in series. The machine is preferably an axial airgap device wherein the stator assembly has a magnetic core made from low loss, high frequency material. A high pole count permits the electrical device to operate at high commutating frequencies, with high efficiency, high power density and improved performance characteristics.Type: GrantFiled: December 18, 2004Date of Patent: February 20, 2007Assignee: Light Engineering, Inc.Inventors: Andrew D. Hirzel, David R. Crecelius
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Patent number: 7157820Abstract: Plurality of air gaps are formed in a torus-shaped stator body of the resolver. If a straight line were drawn from a center point of the stator body toward the outside in the radial direction of the stator body and the straight line were rotated 360 degrees about the center point, the straight line would intersect with at least one of an inside air gap and an outside air gap. Therefore, magnetic flux (i.e., noise caused by magnetism) that has penetrated from the outer peripheral surface side of the stator body will always pass through a portion of the stator body that is to the outside in the radial direction of the air gaps, such that a large portion of the magnetic flux is eliminated by the air gaps.Type: GrantFiled: July 28, 2005Date of Patent: January 2, 2007Assignees: Aisin AW Co., Ltd, Aismagama Seiki Co., Ltd.Inventors: Satoshi Murakami, Daiki Suyama, Masuho Sakakibara, Kanji Kitazawa, Hiromi Makiuchi
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Patent number: 7148599Abstract: An iron core winding is such that a winding of a given polarity is coiled in series so that the beginning of each coiling and the ending of each coiling cross on a magnetic pole that is positioned in the direction of a circumference of the iron core. When the winding of the magnetic core with the given polarity is completed, the winding direction is reversed and the remainder of the winding, which has the opposite polarity, is coiled in series so that the beginning of each coiling and the ending of each coiling cross in the reversed direction. A variable reluctance angle detector uses the iron core winding. The number of windings of the output winding is the same for each pole, and an induced voltage output of a sine wave is obtained.Type: GrantFiled: February 18, 2004Date of Patent: December 12, 2006Assignee: Minebea Co., Ltd.Inventors: Naohiko Aoyama, Hiroyuki Kujirai
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Patent number: 7135860Abstract: A variable reluctance resolver has a rotor with magnetic poles with 2× or greater axis combination angles, and is structured so that reliable and accurate zero point detection can be carried out. Concave and convex portions are provided on at least two, but fewer than all, of the magnetic poles of the rotor, and the zero point detection winding is provided on a plurality of electrical poles of the stator. Two or more zero point detection signals are generated simultaneously by a plurality of zero point detection windings. Therefore, even if a portion of the zero point detection signals is lost, the zero point can still be identified based on the correlation between the two or more zero point detection signals.Type: GrantFiled: July 29, 2004Date of Patent: November 14, 2006Assignee: Minebea Co., Ltd.Inventors: Taiichi Miya, Taro Kasahara, Toshisada Koyama
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Patent number: 7119536Abstract: A deviation angle detector enlarges the application range by enlarging the detectable deviation angle range. The deviation angle detector has two resolvers, which have rotors, stators, and single excitation windings and multiple output windings that are coiled around the stators. The difference in rotation angles of the resolvers is detected as a deviation angle ?? by calculating the output signal that corresponds to the rotation angles of the resolvers digitally or in analog. The corresponding output windings of the resolvers are connected in series and the output signals are extracted from the serially connected output windings and calculated digitally or in analog.Type: GrantFiled: January 29, 2004Date of Patent: October 10, 2006Assignee: Minebea Co., Ltd.Inventors: Taiichi Miya, Mutsumi Matsuura
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Patent number: 7088025Abstract: A variable-reluctance resolver includes a rotor and a stator. The rotor includes axially connected first and second rotor portions. The first rotor portion has n salient poles provided about a center axis at uniform angular intervals, where n is an arbitrary integer not less than 3. The second rotor portion has (n?1) salient poles provided about the center axis at uniform angular intervals. The stator has a plurality of magnetic poles provided on an inner circumferential surface thereof. An excitation coil and output coils for shaft angle multipliers of n× and (n?1)× are provided on the magnetic poles in order to output sine and cosine outputs having a phase difference of 90 degrees therebetween. A rotational angle sensor includes the VR resolver and a calculation section for calculating a resolver signal for a shaft angle multiplier of 1× from signals output from the VR resolver.Type: GrantFiled: February 18, 2005Date of Patent: August 8, 2006Assignee: Minebea Co., Ltd.Inventors: Hiroyuki Kujirai, Taiichi Miya, Mutsumi Matsuura, Nao Aoki
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Patent number: 7078840Abstract: A brushless rotary electric machine includes a stator having an annular armature core with first radial teeth at the outer periphery thereof and second radial teeth at the inner periphery thereof and an armature winding wound between the teeth, a rotor having a pair of first and second rotary cores disposed tandem in the axial direction thereof, and a field coil. Each of the first and second rotary cores has a pair of coaxial outer and inner cylindrical pole members respectively facing the first and second radial teeth, a center core and a disk member magnetically connecting the pair of coaxial cylindrical pole members and the center core. The stator is accommodated by a first space defined by the outer and inner cylindrical members of the pair of first and second rotary cores. The field coil is accommodated by a second space defined by the inner cylindrical pole member and the center core of the first and second rotary cores.Type: GrantFiled: December 2, 2005Date of Patent: July 18, 2006Assignee: Denso CorporationInventor: Shin Kusase
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Patent number: 7078839Abstract: The present invention relates to a self-bearing step motor, and more particularly, to self-bearing step motor system and a control method thereof, wherein a rotor can be supported by magnetic force without adding an additional winding for supporting the rotor to a step motor having no mechanical bearing for supporting the rotor.Type: GrantFiled: February 19, 2002Date of Patent: July 18, 2006Inventor: Dae-gon Kim
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Patent number: 7064462Abstract: A method of assembling a power tool, a power tool, a method of assembling an electrical device, and an electrical device includes a switched reluctance motor. The electrical device is preferably a hand-held power tool, however, any type of electrical device that includes a switched reluctance motor may benefit from any number of aspects of the invention. In one independent aspect, the invention provides a construction that reduces tolerance stack-up. In another independent aspect, the invention provides a self-contained electronics package that plugs into a switched reluctance motor to provide control operation of the switched reluctance motor. In another independent aspect, the invention provides enhanced cooling that increases the efficiency of the electrical device using a switched reluctance motor. In another independent aspect, the invention provides an encapsulated magnet that allows for contaminant free motor control over the life of the SR motor.Type: GrantFiled: February 4, 2003Date of Patent: June 20, 2006Assignee: Milwaukee Electric Tool CorporationInventors: David A. Hempe, Gary D. Meyer, Roderick N. Ebben, Jeffrey M. Brozek
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Patent number: 7030532Abstract: A variable reluctance resolver has a rotor which includes a noncircular core and which is rotatably supported inside a stator with a gap therebetween. The shape of the rotor is such that the gap permeance, which is based on the gap, varies according to a sine function of the rotational angle. Each of the salient poles of the rotor has an outer periphery comprising an arc of radius r centered on a point which is offset from the center of the rotor by a prescribed offset distance. The outer periphery of each salient pole does not extend to the inner periphery of the stator.Type: GrantFiled: April 12, 2004Date of Patent: April 18, 2006Assignee: Minebea Co., Ltd.Inventors: Masahiro Kobayashi, Hiroyuki Kujirai, Takanobu Koyama, Nao Aoki
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Patent number: 7015615Abstract: A TPSRM may include a stator, having a plurality of poles and a ferromagnetic or iron back material, and a rotor having a plurality of poles and a ferromagnetic or iron back material. A current flowing through coils wound around a first set of the plurality of stator poles induces a flux flow through the first set of stator poles and portions of the stator back material during a first excitation phase. A current flowing through coils wound around a second set of the plurality of stator poles induces a flux flow through the second set of stator poles and portions of the stator back material during a second excitation phase. The numbers of stator and rotor poles for this TPSRM are selected such that substantially no flux reversal occurs in any part of the stator back material as a result of transitioning between the first and second excitation phases.Type: GrantFiled: March 17, 2004Date of Patent: March 21, 2006Assignee: Virginia Tech Intellectual Properties, Inc.Inventors: Krishnan Ramu, Nimal Savio Lobo
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Patent number: 7005771Abstract: A variable reluctance resolver is provided with an output winding having a reduced effect from externally introduced leakage magnetic flux. A variable reluctance resolver is provided with a resolver excitation winding and a resolver output winding wrapped around multiple stator magnetic poles which respectively output rotary angle X and Y components as a rotor turns. Windings are wound such that the polarities of output voltages on output windings wound around a row of three or more stator magnetic poles will be the same; all of the output windings are divided into an even number, two or greater, of groups, and output windings are serially connected in such a way that adjacent group output voltage polarities mutually differ.Type: GrantFiled: July 31, 2003Date of Patent: February 28, 2006Assignee: Minebea Co., Ltd.Inventor: Masahiro Kobayashi
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Patent number: 6958602Abstract: A high-accuracy, 1X VR resolver includes a first rotor portion having (N?1) salient poles, where N is an arbitrary integer not less than 3, a second rotor portion having N salient poles, a first stator portion having an input coil and an output coil for a shaft angle multiplier of (N?1)X are provided, and a second stator portion having an input coil and an output coil for a shaft angle multiplier of NX. A first resolver unit composed of the first rotor portion and the first stator portion, and a second resolver unit composed of the second rotor portion and the second stator portion are disposed in front and rear stages, respectively. The output coil of the stator portion in the front stage is connected to the input coil of the stator portion in the rear stage in such a manner that the output coil of the stator portion in the rear stage outputs an output signal for a shaft angle multiplier of 1X.Type: GrantFiled: February 25, 2005Date of Patent: October 25, 2005Assignee: Minebea Co., Ltd.Inventors: Mutsumi Matsuura, Taiichi Miya, Yoshihito Osanai
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Patent number: 6930423Abstract: According to the present invention, when using a pair of annular stators stacked together, they are deviated from each other so that the projected poles may not overlap each other, whereby continuous winding is possible for each winding. Thus, a reduction in cost is achieved. In the rotation angle detector of the present invention, the first and second annular stators are stacked together such that the projected poles do not overlap each other, with the windings wound around the projected poles being wound continuously.Type: GrantFiled: May 6, 2004Date of Patent: August 16, 2005Assignee: Tamagawa Seiki Kabushiki KaishaInventor: Kanji Kitazawa
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Patent number: 6903477Abstract: An electric machine selectively operates as a generator mode or a motor mode. The electric machine includes a stator core, a multi-phase armature winding, a field coil, a moving core having a plurality of salient poles so as to move relative to the stator core to cross the magnetic field. Field current is supplied to the field coil differently according to operation mode. A portion of the armature winding is short-circuited to form an additional magnetic field that has a phase different from the magnetic field of the field coil. Therefore, the rotary core moves relative to the stator core when the operation mode is in the motor mode.Type: GrantFiled: December 20, 2002Date of Patent: June 7, 2005Assignee: Denso CorporationInventors: Shin Kusase, Tsutomu Shiga
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Patent number: 6894484Abstract: A wheel rotation detecting device including a sensor unit that is supported on a stationary ring which does not rotate even when the wheel is in use, and the rotation of the wheel that is attached to a rotary ring can be detected by a rotation detecting sensor held within the sensor unit. Within the sensor unit, in addition to a rotation detecting sensor, there are disposed other sensors such as a temperature sensor and a vibration sensor, thereby allowing detection of the rotation speed and the rotation number of the wheel supported on the rotary ring, as well as detection of other car driving conditions.Type: GrantFiled: January 24, 2002Date of Patent: May 17, 2005Assignee: NSK Ltd.Inventors: Takeshi Takizawa, Shigeru Endo, Ikunori Sakatani, Tatsunobu Momono, Yasushi Mutoh
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Patent number: 6870295Abstract: An oscillating motor is provided which can be reciprocally rotated within a predetermined rotation region without any conversion device for changing to a linear movement, and which can be simply connected to an existing apparatus. The oscillating motor includes a set of teeth formed on the stator which are configured to engage with a corresponding set of teeth formed on the rotor when the motor is in operation. Alternately formed concave and convex regions on the teeth increase a contact area between the rotor and stator, thus increasing torque and operating efficiency of the motor without increasing size.Type: GrantFiled: October 29, 2001Date of Patent: March 22, 2005Assignee: LG Electronics Inc.Inventors: Jun Young Lim, Yun Chul Jung
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Patent number: 6867522Abstract: A synchronous machine (10), in particular, for a starter-generator of an internal combustion engine, includes a stator, a rotor (22) having a rotor shaft (24), a stack of sheets (28), and squirrel cage (30) non-rotatably connected with the rotor shaft (24) and the stack of sheets (28). The squirrel cage (30) has a short circuit ring (36) on its opposite front ends, which is secured to an annular reinforcement element (40, 42). The reinforcement elements (40, 42) do not overlap adjacent, outer circumferential surfaces of the squirrel cage (32) or the short circuit rings (36).Type: GrantFiled: June 20, 2003Date of Patent: March 15, 2005Assignee: Robert Bosch GmbHInventors: Johannes Vlemmings, Karl-Juergen Roth