With Slots Or Holes To Guide Flux Patents (Class 310/156.57)
  • Patent number: 6512317
    Abstract: The present invention relates to a permanent magnet rotor comprising a rotary iron core formed by stacking a plurality of round steel plates, and a plurality of arc-shaped permanent magnets, wherein said individual arc-shaped permanent magnets of alternation poles are provided in the corresponding openings. In particular, the present invention discloses round-cornered permanent magnets by providing round instead of sharp comers at outer perimeter of two adjacent permanent magnets so as to form triangle-shaped regions. Moreover, to prevent said open areas from being filled up, portions of steel plates or holes through steel plates opposite said open areas are removed or created, respectively, so that magnetic flux leakage is minimized and motor performance is elevated.
    Type: Grant
    Filed: December 26, 2000
    Date of Patent: January 28, 2003
    Assignee: Industrial Technology Research Institute
    Inventors: Ching-Feng Lai, Yu-Choung Chang, Tse-Liang Hsiao, Chun-Chung Yang, Kun-I Liang, Ann Huang
  • Publication number: 20020190595
    Abstract: A single phase line start permanent magnet synchronous motor is started by an interaction between magnetic fields of the coil and of the secondary conductor, and an normal operation can be performed using only the permanent magnet and the operating condenser of small capacity, only the main coil, or only the operating condenser when the synchronous rotating speed is reached and the rotation is started, and therefore an additional direct current supplying device for supplying the direct current and the position sensor for sensing the rotational position of the rotor can be excluded, the structure can be made compactly by constructing the driving circuit simply, and manufacturing cost can be reduced.
    Type: Application
    Filed: January 10, 2002
    Publication date: December 19, 2002
    Inventors: Seung Do Han, Hyoun Jeong Shin, Kwan Yeul Cho, Yoon Hyeo Kim
  • Publication number: 20020171309
    Abstract: Reduction of cogging torque and torque pulsation in the rotor with permanent magnets embedded therein. In a rotating electrical machine comprising a stator 5 with an armature winding wound on the stator core and a rotor 1 with permanent magnet 2 embedded in the rotor core 9, a magnetic flux short circuit preventive hole 3 radially extending from the circumferential ends of the permanent magnets 2 (in the vicinity of q-axis) to the vicinity of outer periphery of the rotor core is further extended toward the d-axis (circumferential direction). At the same time, the distance between the outer periphery of the magnetic flux short circuit preventive hole 3 and that of the rotor core is increased gradually in conformity to the approach to d-axis side from q-axis.
    Type: Application
    Filed: September 27, 2001
    Publication date: November 21, 2002
    Inventors: Shinichi Wakui, Haruo Koharagi, Ryoichi Takahata, Takashi Seshimo, Hiroshi Hirayama, Miyoshi Takahashi
  • Publication number: 20020163271
    Abstract: Keybar voltages in electric machines are reduced by electromagnetically optimizing the positioning of the keybars with respect to stator winding phase belts, the selection of the number of keybars, the selection of the number of stator slots, and/or the direction of rotation of a rotor with respect to the stator.
    Type: Application
    Filed: May 1, 2001
    Publication date: November 7, 2002
    Inventors: Manoj Ramprasad Shah, Sameh Ramadan Salem
  • Patent number: 6472789
    Abstract: The invention relates to an electric rotary machine having a stator with several slots for receiving field coils and a rotor having excitation means with main permanent magnets housed in a rotor structure to define a plurality of successive North and South poles (N. S.). The invention is characterized in that the rotor structure has a plurality of barrier zones substantially impermeable to the magnetic current which are arranged with respect to the main magnets such that a substantial part of a magnetic current input in a main magnet is derived at least from one South pole and adjacent to the magnet and a substantial part of a magnetic current output by one magnet is directed toward at least one North pole adjacent to the magnet. Thus, the invention provides a lighter, less costly and more efficient rotor. The invention is applicable to starters or AC-starters for motor vehicles.
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: October 29, 2002
    Assignee: Valeo Equipement Electriques Moteur
    Inventor: Antoine Dokou Akemakou
  • Publication number: 20020145353
    Abstract: A permanent magnet type rotating electrical machine characterized by reduced vibration and noise, or improved efficiency. In a permanent magnet type rotating electrical machine comprising a stator 10 provided with concentrated winding and a rotor with permanent magnets 24 embedded in the rotor core 21, induced voltage waveform is improved by formation of two grooves or holes (flux barriers) extending in the axial direction for each magnetic pole on the bridge 25 of the core between the permanent magnet insertion hole 23 and the outer surface of rotor 20 in such a way that they are placed at an equally spaced interval over the entire circumference of the rotor 20.
    Type: Application
    Filed: September 26, 2001
    Publication date: October 10, 2002
    Inventors: Mamoru Kimura, Haruo Koharagi, Hiroyuki Mikami, Miyoshi Takahashi
  • Patent number: 6445100
    Abstract: In order to realize a permanent magnet dynamo electric machine which permits a high speed rotation, the permanent magnet dynamo electrIc machine including a stator 20 having a stator iron core 22 in which a stator winding 24 is wound, and a rotor 30 facing the inner circumference of the stator 20 and rotatably supported thereby, the rotor 30 having a rotor iron core 32 and a plurality of permanent magnets 36 arranged inside the rotor iron core 32 so as to face the stator iron core 22, wherein the rotor iron core 32 is provided with the same number of permanent magnet insertion holes 34 as the plurality of permanent magnets 36 for receiving the same at positions where ratio R1/R0 is equal to or more than 0.85, wherein R0 is the radius of the rotor 30 and R1 is the radius of an imaginary circle drawn by inscribing the faces of the plurality of permanent magnets 36 at the side remote from the stator 20.
    Type: Grant
    Filed: December 5, 2000
    Date of Patent: September 3, 2002
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Fumio Tajima, Yutaka Matsunobu, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi, Keiji Oda
  • Publication number: 20020063486
    Abstract: For achieving a constant capacity range by way of field weakening of a permanent magnet excited drive the magnetic transverse resistance (Rm) of the rotor plate pack is increased by pole gaps (P1, P2), which are produced by milling into the upper surface (O) of the rotor plate section (L), or are punched into the rotor plate section (L), whereby a covering of the poles of Tp in the range of from 70% to 80% has been shown to be particularly advantageous.
    Type: Application
    Filed: August 23, 2001
    Publication date: May 30, 2002
    Inventor: Gerhard Huth
  • Publication number: 20020047435
    Abstract: Permanent magnets are arranged to be supported by the provision of permanent magnet position-locating projections (12) in permanent magnet embedding holes (5). By optimizing the shape of thin-wall regions (18) and (19) within rotor core (4), leakage of flux generated from the permanent magnets is reduced and the strength of the thin-wall regions where stress is concentrated is ensured.
    Type: Application
    Filed: May 24, 2001
    Publication date: April 25, 2002
    Inventors: Norio Takahashi, Yutaka Hashiba, Kazuto Sakai, Masanori Arata, Yukihiko Kazao, Takashi Araki, Masakatsu Matsubara, Yasuo Hirano
  • Patent number: 6342745
    Abstract: A reluctance type rotating machine includes a stator 1 having armature windings 2 arranged on an inner periphery of the stator 1, a rotor 3 having a magnetic unevenness in the circumferential direction and a plurality of permanent magnets 6 arranged for negating the armature windings' flux passing between adjoining poles. Each magnet 6 is magnetized in a direction different from a direction to facilitate the rotor's magnetization. A magnetic portion 7 is provided between the pole and the interpole of the rotor 3. Owing to the provision of the magnetic portion 7, when the armature windings are not excited, more than 30% of the permanent magnets' flux is distributed in the rotor 3 Similarly, when the machine is loaded, the permanent magnets' interlinkage flux is more than 10% of composite interlinkage flux composed of armature current and the permanent magnets.
    Type: Grant
    Filed: September 13, 2000
    Date of Patent: January 29, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuto Sakai, Masanori Arata, Mikio Takabatake, Yoshio Hashidate, Ryoichi Kurosawa, Yosuke Nakazawa, Tadashi Tokumasu
  • 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: 20010030480
    Abstract: At least one groove 10, two grooves 12 extending toward an axial direction of a rotor 6 is provided on an outer periphery of a rotor iron core 7 or at least one hole 11 is provided in the rotor iron core 7. By the provision of the groove 10 and the two grooves 12 on the outer periphery of the rotor iron core 7 or by the provision of the hole 11 in the rotor iron core, the cogging torque is generated to negate the cogging torque which is generated according to the magnetic fluctuation between the magnetic field of the permanent magnets 8 and a stator 1. As a result, the cogging toque in a whole permanent magnet type rotary machine is reduced.
    Type: Application
    Filed: March 14, 2001
    Publication date: October 18, 2001
    Applicant: Hitachi Ltd.
    Inventors: Yutaka Matsunobu, Fumio Tajima, Shouichi Kawamata, Suetaro Shibukawa, Osamu Koizumi
  • Patent number: 6268677
    Abstract: A rotor is provided for a permanent magnet type rotating machine having a stator 1 with armature windings 11. The rotor 3 includes a rotor core 31 and a plurality of permanent magnets 32 arranged in the rotor core 31 so as to negate magnetic flux of the armature windings 11 passing through interpoles 3b. The rotor 3 is constructed so that the average of magnetic flux in an air gap 2 between the rotor 3 and the stator 1, which is produced by the permanent magnets 32 at the armature windings' de-energized, ranges from 0.1 [T] to 0.7 [T] and the ratio (Lq/Ld) of self-inductance of the magnetic portion in a hard-magnetizing direction (q-axis) to self-inductance in an easy-magnetizing direction (d-axis) under a rated load condition ranges from 0.1 to 0.8. Under these conditions, it is possible to realize the rotating machine which operates as an induction machine at the machine's starting and also operates as an synchronous machine at the rated driving due to smooth pull-in.
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: July 31, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mikio Takabatake, Masanori Arata, Kazuto Sakai, Yutaka Hashiba, Yoshio Hashidate, Norio Takahashi, Koji Oishi, Shiro Amemori