Having A Particular Dimension Patents (Class 310/49.16)
  • Patent number: 9722478
    Abstract: A stepping motor may include a rotor having a rotation shaft and a permanent magnet, a fixed body having a cylindrical stator provided with a plurality of pole teeth so as to face the permanent magnet, an urging member which urges the rotor toward one side in a motor axial line direction, a supported face of the rotor which faces the one side in the motor axial line direction, and a support face of the fixed body which slidably supports the supported face of the rotor on the one side with respect to the supported face. When a first sliding load which is a total sliding load applied to the rotor is “Ta”, a detent torque acted on the rotor is “Td”, and a dynamic torque acted on the rotor by the stator is “Te”, then “Ta”, “Td” and “Te” satisfy the following expression: “Td”<“Ta”<“Te”.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: August 1, 2017
    Assignee: NIDEC SANKYO CORPORATION
    Inventor: Toshio Yamamoto
  • Patent number: 9692274
    Abstract: A motor may include a rotor having a permanent magnet on an outer peripheral face of a rotation shaft and a fixed body having a stator, an opposite-to-output side radial bearing member, and an opposite-to-output side end plate. The opposite-to-output side radial bearing member may be formed with a bearing part, a flange part, and a recessed part recessed toward an output side. An end part on the output side of the bearing part may be located on the output side relative to the end part on the opposite-to-output side of the stator, and an end part on the opposite-to-output side of the rotation shaft protruded toward the opposite-to-output side from the shaft hole may be accommodated in an inside of the recessed part and is located on the output side relative to the end part on the opposite-to-output side of the fixed body in the axial line direction.
    Type: Grant
    Filed: May 30, 2014
    Date of Patent: June 27, 2017
    Assignee: NIDEC SANKYO CORPORATION
    Inventor: Kazumi Furubayashi
  • Patent number: 8704412
    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: Grant
    Filed: June 10, 2011
    Date of Patent: April 22, 2014
    Assignee: Nidec Servo Corporation
    Inventors: Shigeaki Terashita, Yoji Unoki
  • Patent number: 8446063
    Abstract: A claw-pole-type stepping motor includes a stator annularly disposed therein and having a coil, a rotor rotatably disposed inside the stator and having a multiply magnetized permanent magnet and a shaft, an outer yoke provided in the stator and having a cup shape opening toward an axially outside direction an outer circumferential portion provided in the outer yoke and having a cylindrical shape and an inner circumferential portion including first pole teeth, an inner yoke provided in the stator and having second pole teeth provided in an inner circumference thereof and an outer circumferential portion fixed to an inner circumferential surface of the outer circumferential portion of the outer yoke, in which the first pole teeth and the second pole teeth are engaging with each other via a gap in an axial direction and are disposed with respect to the permanent magnet of the rotor via a gap, a fixed portion of the inner yoke and the outer yoke is positioned at the axial inside of an opening end of the cup shape
    Type: Grant
    Filed: April 19, 2011
    Date of Patent: May 21, 2013
    Assignee: Minebea Co., Ltd.
    Inventors: Shuhei Kinpara, Yuzuru Suzuki, Seiya Fujimoto
  • Patent number: 8344561
    Abstract: A stepping motor may include a rotor having a drive magnet and a stator having a drive coil wound in a tube shape and disposed on the drive magnet. The stator may include a first yoke, a second yoke, a plurality of first pole teeth, and a plurality of second pole teeth. The plurality of the first and second pole teeth may be alternately disposed in a circumferential direction of the rotor.
    Type: Grant
    Filed: March 4, 2010
    Date of Patent: January 1, 2013
    Assignee: Nidec Sankyo Corporation
    Inventor: Hisashi Fukuzawa
  • Patent number: 8319392
    Abstract: A motor may include a stator provided with a yoke having a plurality of pole teeth and an exciting coil and a rotor disposed in a circular space surrounded by the pole teeth. A portion where a difference between an inner side area of the pole tooth facing the rotor and an outer side area of the pole tooth facing the exciting coil is larger than a difference between the inner side area and the outer side area of the pole tooth where both circumferential direction faces of the pole tooth are formed in faces coincided with normal lines may be provided on a root part of the pole tooth. Further, circumferential direction faces of at least a root part of the pole tooth are formed so as to face the rotor in an inclined manner.
    Type: Grant
    Filed: May 6, 2010
    Date of Patent: November 27, 2012
    Assignee: Nidec Sankyo Corporation
    Inventor: Hisashi Fukuzawa
  • Patent number: 8288900
    Abstract: A stepping motor includes a rotor assembly and a stator assembly including two stator units axially coupled to each other. The two stator units each include a pair of yokes which each include a base portion and a plurality of pole teeth extending from the base portion and which are disposed such that each of the pole teeth of one yoke and each of the pole teeth of the other yoke are arranged alternately in the circumferential direction. The pole teeth are shaped symmetric and each include a pair of slant sides inclined so as to become closer to each other with an increase of distance from the base portion, and the slant sides of adjacent pole teeth are located close to each other wherein a magnetic pole gap between the adjacent pole teeth pole teeth is about 0.2 times as large as the thickness of the pole teeth.
    Type: Grant
    Filed: July 28, 2010
    Date of Patent: October 16, 2012
    Assignee: Minebea Co., Ltd.
    Inventors: Takeshi Matsuno, Yoshiya Yamamura, Hiroaki Itahashi, Shigeki Miyaji, Yukihiro Terada
  • Patent number: 7977828
    Abstract: A stepping motor may include a rotor having a drive magnet and a stator having a drive coil wound in a tube shape and disposed on the drive magnet. The stator may include a first yoke, a second yoke, a plurality of first pole teeth provided in the first yoke, and a plurality of second pole teeth provided in the second yoke. The plurality of the first pole teeth and the second pole teeth may be alternately disposed in a circumferential direction of the rotor.
    Type: Grant
    Filed: November 1, 2010
    Date of Patent: July 12, 2011
    Assignee: Nidec Sankyo Corporation
    Inventor: Hisashi Fukuzawa
  • Publication number: 20110050009
    Abstract: A stepping motor may include a rotor having a drive magnet and a stator having a drive coil wound in a tube shape and disposed on the drive magnet. The stator may include a first yoke, a second yoke, a plurality of first pole teeth provided in the first yoke, and a plurality of second pole teeth provided in the second yoke. The plurality of the first pole teeth and the second pole teeth may be alternately disposed in a circumferential direction of the rotor.
    Type: Application
    Filed: November 1, 2010
    Publication date: March 3, 2011
    Applicant: NIDEC SANKYO CORPORATION,
    Inventor: Hisashi FUKUZAWA
  • Patent number: 7795774
    Abstract: A claw pole type motor includes first and second claw poles opposed to each other and each including a radial yoke portion having an inner diameter side and an outer diameter side, a plurality of pole portions arranged on the inner diameter side, and axially extended, and an outer peripheral side yoke portion extending on the outer diameter side. A stator core is provided having an inner diameter side, and is formed so as to cause the pole portions of the first claw pole to be meshed with the pole portions of the second claw pole. A rotor is arranged on the inner diameter side of the stator core with a circumferential gap being defined therebetween. In order to provide high efficiency while simplifying manufacturing, the first and second claw poles are formed by compacting of magnetic powder.
    Type: Grant
    Filed: July 20, 2007
    Date of Patent: September 14, 2010
    Assignee: Hitachi Industrial Equipment Systems Co.
    Inventors: Yuji Enomoto, Motoya Ito, Kenji Miyata, Chio Ishihara, Ryoso Masaki, Yasuaki Motegi, Kouki Isozaki, Tadashi Sato