Patents Examined by K. Imayoshi Tamai
  • Patent number: 6114787
    Abstract: A sensor output for each axis of a five-axis control type magnetic bearing spindle is input to a multiplexer, time divisionally selected, converted to a digital signal by an A/D converter, and then applied to an MPU for control operation. Subsequently, a control signal is converted to an analog signal by a D/A converter for every axis, and A/D conversion, control operation and D/A conversion are sequentially processed.
    Type: Grant
    Filed: September 8, 1997
    Date of Patent: September 5, 2000
    Assignee: NTN Corporation
    Inventor: Nobuyuki Suzuki
  • Patent number: 6025667
    Abstract: In an electric motor, such as a DC brushless motor or the like, having a permanent magnet in a rotor, each magnetic pole is formed of three permanent magnets, and the permanent magnets are made of at least two kinds of magnetic materials represented by ferrite magnet and rare-earth magnet. Thus, in a permanent magnet rotor type electric motor, a reluctance torque and a magnetic flux density can be selectively established, and cost is reasonable, corresponding to the quality.
    Type: Grant
    Filed: September 24, 1998
    Date of Patent: February 15, 2000
    Assignee: Fujitsu General Limited
    Inventors: Kenji Narita, Takashi Suzuki, Hiroyuki Okudera, Yuji Kawai, Yuji Souma, Koji Kawanishi, Yoshichika Fukuda
  • Patent number: 5977669
    Abstract: A three-wave rectifying unit of an AC generator has a plus-side cooling fin, a minus-side cooling fin and a DC-output terminal. The DC-output terminal is made of a metal plate which is harder than the plus-side cooling fin to provide tight mechanical connection. The DC-output terminal, the plus-side cooling fin, a plus-side brush terminal and a plus-side terminal of a voltage regulator are fastened together and electrically connected by a screw which is screwed into a portion of the DC-output terminal.
    Type: Grant
    Filed: November 8, 1996
    Date of Patent: November 2, 1999
    Assignee: Denso Corporation
    Inventors: Ko Yoshida, Tamaki Suzuki, Yusuke Kawano
  • Patent number: 5942825
    Abstract: An electric motor having a rotor and stator includes a magnetic hollow rotating shaft to which the rotor is fixed. A magnetic cylindrical bearing is inserted into the magnetic hollow rotating shaft such that a radial repulsive force is generated between the magnetic hollow rotating shaft and the magnetic bearing. A first fixed magnetic member is disposed at a top of the magnetic cylindrical bearing, and a rotating magnetic member is disposed at a top of the magnetic hollow rotating shaft such that the magnetic hollow rotating shaft can be supported by axial repulsive force generated between those magnetic members. The magnetic members are vertically adjustable for varying the axial clearance therebetween.
    Type: Grant
    Filed: December 3, 1997
    Date of Patent: August 24, 1999
    Assignee: Samsung Electronics Co., LTD.
    Inventor: Chang-Woo Lee
  • Patent number: 5942821
    Abstract: A holder member fixing apparatus of a motor facilitates the fixing of a holder member without requiring a separate jig by fixing the holder member to the upper portion of a substrate via a printed circuit board and forming a position setting hole for previously setting the fixing position of the holder member into the printed circuit board. The apparatus includes a holder member which is inserted with a rotating shaft in the center thereof and is formed with a backing stand for placing a rotor thereon to the lower portion of the outer periphery thereof, and a substrate having a plurality of couplers to the upper portion thereof to be fixedly coupled by being inserted with a plurality of brackets radially-formed along the outer periphery of the backing stand. Also, a printed circuit board fixedly installed to the upper portion of the substrate while overlapping thereon is formed with a position setting hole for leading the holder member to place to a correct position, thereby requiring no separate jig.
    Type: Grant
    Filed: October 3, 1997
    Date of Patent: August 24, 1999
    Assignee: Samsung Electro-Mechanics Co. Ltd.
    Inventor: Seong Ho Shin
  • Patent number: 5917261
    Abstract: A motive power generating apparatus utilizing magnetic flux from permanent magnets providing higher efficiency and torque is disclosed. An apparatus according to one embodiment of the present invention comprises a pair of disc-shaped rotors 10 and 20, a pair of ring-shaped stators 30 and 40, a rotational shaft 50, a permanent magnet 60, and a current controller 80. Each rotor 10, 20 is a disc-shaped member formed of magnetic material. Each stator 30, 40 further includes twelve electromagnets 32, 42 provided along the outer periphery of each disc-shaped rotor 10, 20 at intervals of thirty degrees. Each electromagnet 32, 42 has an armature 32a, 42a and a winding 32b, 42b. Each rotor 10, 20 contains six sets of protruding poles 10a, 20a disposed around the outer periphery thereof at intervals of sixty degrees. Each rotor 10, 20 is magnetized in opposite polarities by the permanent magnet 60 disposed therebetween.
    Type: Grant
    Filed: September 24, 1998
    Date of Patent: June 29, 1999
    Assignee: Nihon Riken Co., Ltd.
    Inventor: Teruo Kawai
  • Patent number: 5777411
    Abstract: A geared electric motor 1 used for power window apparatuses, for example, which is provided with an mature 7 having an armature shaft 7a, an output shaft 8 connected with the armature shaft 7a through a worm gear pair (7a7 and 17) and two friction plates 9 and 10 to be in contact with both end faces of the armature shaft 7a. The armature shaft 7a of this motor 1 is prevented from rotation by frictional resistance generating between the friction plates 9, 10 and the armature shaft 7a even if the output shaft 8 is applied with rotatory force.
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: July 7, 1998
    Assignee: Jidosha Denki Kogyo Kabushiki Kaisha
    Inventors: Fumio Nakajima, Takeo Furuya, Sumio Furukawa, Toshihiro Negishi
  • Patent number: 5763969
    Abstract: An integrated motor drive system includes a variable speed electric motor, a fan connected to the electric motor to generate an air flow as the motor rotates, and a motor drive connected to the electric motor, the drive including a heat sink disposed between the motor and the drive and having a plurality of asymmetrically spaced apart heat transfer fins transferring heat generated by power components in the drive to the air flow. The fan is connected to a one of either the rotor of the variable speed motor or to an auxiliary fan motor controlled independently of the variable speed motor. A fan shroud on one end of the motor acts as an air duct member adapted for dividing and directing the flow of air from the fan to sets of heat transfer fins on the heat sink. A method of operating the drive integrated type motor system includes generating motor speed command signals in the drive based on inputs from an operator through an operator interaface unit on the drive.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: June 9, 1998
    Assignee: Reliance Electric Industrial Company
    Inventors: Larry J. Metheny, Douglas H. Sudhoff, Anthony D. Thompson, Richard J. Budzynski
  • Patent number: 5760511
    Abstract: A second circuit B which is composed of a band-pass filter circuit (5) which takes out a rotating body position signal input from a sensor (1) while scarcely varying a phase within a range including a normal rotation frequency and a reverse rotation frequency of a rotating body, a gain circuit (6) for controlling a gain of an output signal from the bandpass filter circuit (5) and a second notch filter circuit (7) for attenuating components having frequencies lower than the natural frequency of an output signal from a gain circuit (6) is disposed separately from a main circuit A, and an output signal from the second notch filter circuit (7) is positively fed back to the main circuit A through an adding circuit (8).
    Type: Grant
    Filed: February 25, 1997
    Date of Patent: June 2, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tohru Nakagawa, Isao Tashiro, Yoshihiro Ikemoto