Having Particular Stator-pole To Rotor-pole Relationship Patents (Class 310/49.37)
  • Patent number: 11581762
    Abstract: A claw-pole motor having a rotor assembly orientated about a longitudinal axis, a stator assembly having a first plurality of stator teeth and a second plurality of stator teeth orientated radially about the longitudinal axis and extending axially in opposite directions to each other and alternating about the longitudinal axis, a first gap in the stator assembly orientated about the longitudinal axis, a second gap orientated about the longitudinal axis and extending both axially and radially between the first plurality of stator teeth and the second plurality of stator teeth, first electromagnetic windings disposed in the first gap and second electromagnetic windings disposed in the second gap, the first and second windings configured to be selectively energized to exert a torque on the rotor assembly.
    Type: Grant
    Filed: August 30, 2019
    Date of Patent: February 14, 2023
    Assignee: Moog Inc.
    Inventor: Robert P. Gerbetz
  • Patent number: 9780704
    Abstract: An electrical motor system comprises a switched reluctance electrical motor comprising a rotor section and a stator section, the rotor section comprising a plurality of rotor teeth and the stator section comprising a plurality of stator teeth, the stator teeth wound with respective coils. Coil driver circuitry is coupled to the coils of the stator teeth and controls an independent phase of electrical power to each coil of the plurality of stator teeth. The coils of the stator teeth each have an inductance which absorbs electrical energy provided to that coil by the coil driver circuitry and subsequently releases at least a portion of the electrical energy back to the coil driver circuitry when that coil is not being actively driven by the coil driver circuitry.
    Type: Grant
    Filed: September 17, 2014
    Date of Patent: October 3, 2017
    Assignee: ARM Limited
    Inventor: David Pietromonaco
  • Patent number: 9006941
    Abstract: A permanent magnet-type stepping motor broadly includes: a movable member (e.g., a rotor) having a number of magnetic poles on a surface thereof, with adjacent poles being of opposite polarity, the number of poles being a function of a constant, the number of phases and a desired step interval; and a stationary member (e.g., a stator) having a number of equally-spaced teeth arranged to face toward said movable member surface, each of said teeth having a plurality of fingers arranged to face toward said movable member surface, the number of said teeth being a whole integer that is a function of a constant, the number of said poles, the number of said fingers on each stator tooth, and the number of phases.
    Type: Grant
    Filed: August 29, 2008
    Date of Patent: April 14, 2015
    Assignee: Moog Inc.
    Inventor: Steve Zong-Ping Zhao
  • Publication number: 20140283732
    Abstract: A display module has a two-phase motor which includes a rotor including N pairs of poles magnetised radially, in alternate directions, N being equal to 3 or 5, and a stator part including at least two W-shaped circuits made from radial pole teeth extending inwards from a peripheral closed belt and including a coil on a central leg of the W, said W-shaped circuits being arranged in such a way that when the central tooth of one of the W-shaped circuits is positioned facing a rotor magnetic transition, at least one central tooth of another W-shaped circuit is positioned facing a rotor magnetic pole. Said display module additional includes at least one specific mechanical interaction (between the rotor and the stator, comprising angular friction at a force that is substantially constant depending on the speed of the rotor relative to the stator, and at a value lower than the torque produced by the electromagnetic interaction between the rotor and the stator.
    Type: Application
    Filed: November 13, 2012
    Publication date: September 25, 2014
    Applicant: MOVING MAGNET TECHNOLOGIES (MMT)
    Inventor: Sébastien Heinrich
  • Patent number: 8704413
    Abstract: An electromagnetic step-by-step wobbling micromotor comprises an inner component and an annular component being external to the inner one. The outer component may be a stator and the inner component a rotor, or vice versa. The inner component has three or more poles with a winding on each pole, and an external surface facing an internal surface of the outer component. During the operation of the micromotor each winding is powered. The external and internal surfaces have toothed surfaces. Each tooth has a peak radius which is different from the valley radius.
    Type: Grant
    Filed: September 28, 2009
    Date of Patent: April 22, 2014
    Assignee: Scuola Superiore di Studi Universitari e di Perfezionamento Sant'Anna
    Inventors: Cesare Stefanini, Paolo Dario, Maria Chiara Carrozza, Sarah De Cristofaro
  • Patent number: 8558486
    Abstract: A d.c. charged particle accelerator comprises accelerator electrodes separated by insulating spacers defining acceleration gaps between adjacent pairs of electrodes. Individually regulated gap voltages are applied across each adjacent pair of accelerator electrodes. In embodiments, the individually regulated gap voltages are generated by electrically isolated alternators mounted on a common rotor shaft driven by an electric motor. Alternating power outputs from the alternators provide inputs to individual regulated d.c. power supplies to generate the gap voltages. The power supplies are electrically isolated and have outputs connected in series across successive pairs of accelerator electrodes. The described embodiment enables an ion beam to be accelerated to high energies and high beam currents, with good accelerator stability.
    Type: Grant
    Filed: December 8, 2010
    Date of Patent: October 15, 2013
    Assignee: GTAT Corporation
    Inventors: Theodore H. Smick, Geoffrey Ryding, William H. Park, Ronald Horner
  • Publication number: 20130249332
    Abstract: There is provided a hybrid stepping motor including a rotor including a plurality of rotor small teeth arranged at an equal pitch on an outer circumferential surface thereof, and a stator including a plurality of salient poles, each including a plurality of stator small teeth arranged to face the outer circumferential surface of the rotor via a gap. The stator small teeth have a predetermined stator tooth thickness and are arranged at a predetermined stator tooth pitch. The rotor small teeth have a predetermined rotor tooth thickness and are arranged at a predetermined rotor tooth pitch. A repulsion area ratio which is a ratio of an area of repulsion poles to a total area of all stator small teeth facing the rotor ranges from 0% to a predetermined threshold value.
    Type: Application
    Filed: March 12, 2013
    Publication date: September 26, 2013
    Applicant: MINEBEA CO., LTD.
    Inventors: Naohiro YOSHIDA, Takeshi SATO, Takatoshi KUWANO
  • Publication number: 20130249331
    Abstract: There is provided a hybrid stepping motor including a rotor including a plurality of rotor small teeth arranged on an outer circumferential surface thereof, and a stator including a plurality of salient poles, each including a plurality of stator small teeth. The stator small teeth have a predetermined stator tooth thickness and are arranged at a predetermined stator tooth pitch, the rotor small teeth have a predetermined rotor tooth thickness and are arranged at a predetermined rotor tooth pitch, and a facing area which is a difference between an area of attraction poles of the stator small teeth and the rotor small teeth and an area of repulsion poles thereof ranges between a maximum value in a parameter space of a dimensional ratio of the stator and/or the rotor and a threshold value of the maximum value.
    Type: Application
    Filed: March 12, 2013
    Publication date: September 26, 2013
    Applicant: MINEBEA CO., LTD.
    Inventors: Naohiro YOSHIDA, Takeshi SATO, Takatoshi KUWANO
  • Publication number: 20130154405
    Abstract: A hybrid rotary electrical machine that obtains a deviation angle of about one half of a pole teeth pitch between magnetic teeth of two rotor magnetic pole members gripping a permanent magnet of a rotor including rotor magnetic pole members that include the magnetic teeth at an equal pitch T on a surface thereof. The rotor magnetic pole members include cutout portions on the inner circumferential surface or the outer circumferential surface of the rotor magnetic pole members in a specified positional relationship with respect to the magnetic teeth. The cutout portions of one of the rotor magnetic pole members are axially aligned with the cutout portions of the other rotor magnetic pole member turned upside down so the magnetic teeth of one of the rotor magnetic pole members have a phase difference of about T/2 with respect to the magnetic teeth of the other rotor magnetic pole member.
    Type: Application
    Filed: August 2, 2012
    Publication date: June 20, 2013
    Applicant: NIDEC SERVO CORPORATION
    Inventors: Nguyen Thanh TRUNG, Noriyoshi KIKUCHI
  • Publication number: 20110304225
    Abstract: A rotary electric machine includes a stator in which windings are arranged around a plurality of main poles of a stator core, and a hybrid type rotor arranged with an air gap between the stator and the rotor has a step angle for the rotor of about 4.09° and uses metal bearings for supporting a rotor shaft of the rotor. Setting of the step angle for the rotor to be about 4.09° can make a rotation angle of the rotor caused by excitation of the windings by an input pulse signal larger as compared with a typical motor having a step angle of about 1.8°. With this unique arrangement, the rotor can be rotated at higher speeds, increasing the motor efficiency. Therefore, the motor output at approximately the same level as that of a conventional motor can be obtained without keeping the air gap high precision. Due to this, even if inexpensive slide bearings, i.e.
    Type: Application
    Filed: June 10, 2011
    Publication date: December 15, 2011
    Applicant: NIDEC SERVO CORPORATION
    Inventors: Shigeaki TERASHITA, Yoji UNOKI
  • Patent number: 7990019
    Abstract: An electric motor is provided which includes a stator, in which field magnets are fixedly and radially installed on a circular panel-shaped base. A coaxial cylindrical rotor is coupled to a shaft and is configured to allow the stator to be located at an inside thereof, the rotor being configured such that magnets, having different polarities to form each pair, are attached on an outer cylinder and an inner cylinder of the rotor and are arranged opposite each other. A rotary magnet plate is coupled to the shaft on a top of the cover, and is provided with a number of magnets corresponding to a number of pairs of the rotor magnets. The respective pairs of rotor magnets are arranged on the outer and inner cylinders while being spaced apart from each other by a predetermined interval.
    Type: Grant
    Filed: October 15, 2008
    Date of Patent: August 2, 2011
    Inventor: Sam Kyung Sung
  • Patent number: 7781924
    Abstract: A drive apparatus which is small in size, short in axial length, low in cost, and high in output. A stepping motor as the driving apparatus includes a first coil, a second coil, a magnet, and a rotor comprised of a core and a rotary shaft. First through fourth outer magnetic pole portions are opposed to the outer peripheral surface of the magnet with a predetermined gap between them. The first and the second coils are disposed adjacent to the magnet in an axial direction of the rotary shaft and disposed at respective ends of the rotary shaft. The first and second outer magnetic pole portions are inserted inside the first and second coils, respectively. As viewed in the circumferential direction of the magnet, the third and fourth outer magnetic pole portions are disposed close to the first and second outer magnetic pole portions, respectively.
    Type: Grant
    Filed: July 25, 2006
    Date of Patent: August 24, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Masao Mizumaki
  • Patent number: 7755229
    Abstract: A hybrid step motor comprises a stator, a rotor assembly, a magnet and a mandrel. The rotor assembly and the magnet are mounted on the mandrel and are disposed in the stator. The proportion of a stator outer diameter to a stator inner diameter is 1:0.475 to 1:0.6. The proportion of the stator outer diameter to a rotor outer diameter is 1:0.5125 to 1:0.5875. The proportion of a first rotor thickness to a magnet thickness to a second rotor thickness is 0.236:0.09:0.236 optimally. The proportion of the rotor outer diameter to a magnet outer diameter is 0.54:0.45. By such arrangements, the optimal proportion is formed and the output efficiency is improved.
    Type: Grant
    Filed: August 9, 2008
    Date of Patent: July 13, 2010
    Assignee: Hiwin Mikrosystem Corp.
    Inventors: Chia-Ming Chang, Chia-Chun Wei
  • Patent number: 7728465
    Abstract: There is provided a hybrid stepping motor comprising the following: a first rotor yoke and a second rotor yoke, each of the rotor yokes having a plurality of rotor teeth on a periphery thereof; a rotating shaft located between the first and second rotor yokes and supporting the first and second rotor yokes on a same axis, the rotating shaft including at least one permanent magnet magnetized in a direction of the axis; and a plurality of stator yokes, each of the stator yokes having a core portion, a coil wound around the core portion, and a plurality of stator teeth extending parallel to the axis from opposed end portions of the core portion, the stator yokes being disposed at regular intervals around the rotating shaft so that a constant air gap is maintained between radially inward surfaces of the stator teeth and radial end surfaces of the rotor teeth. A positive current is applied to the opposed and paired coils of said coils and a negative current is applied to the rest coils of said coils.
    Type: Grant
    Filed: December 31, 2007
    Date of Patent: June 1, 2010
    Assignee: Korea Institute of Science and Technology
    Inventors: Seung Jong Kim, Jong Min Lee, Woo Yeon Kim
  • Patent number: 7714466
    Abstract: To realize reduction in vibration and noise while utilizing reluctance torque, a rotating electrical machine includes: a rotor having permanent magnets disposed in a cylindrical surface coaxial with a rotary shaft; and a stator having an annular stator core disposed coaxially with the rotary shaft, and a annular coil for magnetizing the stator core. The stator core has an annular part covering the annular coil, claws disposed at equal intervals in an inner radius surface of the annular part and extending axially, and magnetic gaps formed between neighboring claws. The number of claws is equal to the number of permanent magnets, and magnet flux in a direction orthogonal to a center axis of the magnetic pole of the permanent magnet at right angles in electric angle is larger than magnetic flux in the center axis direction generated between neighboring permanent magnets. Metal interpoles are provided between neighboring permanent magnets.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: May 11, 2010
    Assignees: Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Powdered Metals Co., Ltd., Japan Servo Co., Ltd.
    Inventors: Masashi Kitamura, Fumio Tajima, Shigeru Kakugawa, Yuji Enomoto, Motoya Ito, Ryoso Masaki, Shoji Ohiwa, Chio Ishihara
  • Patent number: 7635931
    Abstract: In a stepping motor including two stators and a rotor having two magnets, three dimensional relations, specifically a relation of Lm/Ls, another relation of d/2Lm, and still another relation d/D, are optimally determined while satisfying their respective ranges: 0.35?Lm/Ls?0.45; 0.77?d/2Lm?1.10; and d/D?0.45, where Lm is the axial dimension of the magnet, Ls is the axial dimension of the stator, d is the outer diameter of the magnet, and D is the outer diameter of the stator, whereby a space for accommodating a sufficient number of coil turns is secured maximally in the stator, and the inertia and the cogging torque of the rotor are reduced maximally, which leads to producing the highest possible torque at a high rotation speed range required.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: December 22, 2009
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Takayuki Yamawaki, Masaki Kagawa, Hiroyuki Furusaki