Patents by Inventor Takeyoshi Miyashita

Takeyoshi Miyashita has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7884516
    Abstract: A motor may include a rotor provided with a rotor shaft, a cylindrical bearing made of resin material and provided with a bearing part for rotatably supporting a shaft end of the rotor shaft, and a bearing holder provided with a through-hole into which the cylindrical bearing is inserted. The cylindrical bearing is slidably held in the through-hole and at least one of a first end face where the bearing part is formed and a second end face which is an opposite end face to the first end face is formed with a ring-shaped groove. Therefore, a wall thickness of resin for forming the bearing can be made thinner and thus shrinkage of the side wall part of the bearing which faces an inner peripheral face of the through-hole of the bearing holder is reduced.
    Type: Grant
    Filed: February 28, 2008
    Date of Patent: February 8, 2011
    Assignee: Nidec Sankyo Corporation
    Inventors: Shingo Iwashima, Takeyoshi Miyashita
  • Patent number: 7635935
    Abstract: A motor may include a bearing made of resin for rotatably supporting one end part of the rotor shaft, and an urging member attached to a bearing holder and abutted with a pressurization face of the bearing to urge the bearing toward a side of the rotor shaft. A molding material injection gate trace (projection) which has been used when the bearing is resin-molded is positioned at a center portion of the pressurization face. The molding material injection gate trace may be positioned in a recessed part which is formed at a roughly center portion of the pressurization face of the bearing. Further, the urging member may include an urging piece which is formed by cutting a center portion of a metal plate in a ring shape and an opening part is formed in the urging piece.
    Type: Grant
    Filed: March 21, 2007
    Date of Patent: December 22, 2009
    Assignee: Nidec Sankyo Corporation
    Inventors: Hiroyuki Sonohara, Takeyoshi Miyashita
  • Publication number: 20090200877
    Abstract: A stepping motor is provided with a rotor having with a rotor shaft A permanent magnet is attached to an outer peripheral side of the rotor shaft and a stator having pole teeth faces the permanent magnet in a radial direction. The stepping motor is characterized in that the rotor shaft is formed of aluminum or aluminum alloy.
    Type: Application
    Filed: June 22, 2005
    Publication date: August 13, 2009
    Inventors: Yoshiaki Koshida, Toshio Yamamoto, Takeyoshi Miyashita
  • Publication number: 20080238229
    Abstract: A motor may include a rotor provided with a rotor shaft, a cylindrical bearing made of resin material and provided with a bearing part for rotatably supporting a shaft end of the rotor shaft, and a bearing holder provided with a through-hole into which the cylindrical bearing is inserted. The cylindrical bearing is slidably held in the through-hole and at least one of a first end face where the bearing part is formed and a second end face which is an opposite end face to the first end face is formed with a ring-shaped groove. Therefore, a wall thickness of resin for forming the bearing can be made thinner and thus shrinkage of the side wall part of the bearing which faces an inner peripheral face of the through-hole of the bearing holder is reduced.
    Type: Application
    Filed: February 28, 2008
    Publication date: October 2, 2008
    Applicant: NIDEC SANKYO CORPORATION
    Inventors: Shingo IWASHIMA, Takeyoshi MIYASHITA
  • Publication number: 20070262660
    Abstract: A stepping motor may include a rotor and a stator assembly. The stator assembly may include a first coil, a second coil, a first stator core and a second stator core. Each of the stator may include an end plate part for forming a rotor insertion hole and a plurality of pole teeth bent from an inner circumferential edge of the rotor insertion hole. The end plate part may be formed in a rectangular shape which has a pair of facing long sides extended in a direction where the first coil and the second coil are disposed. Further, portions of one of the first and the second stator cores, which face tip end portions of the pole teeth formed from the other stator core, are formed as cutout portions by cutting out in an outer radial direction from the rotor insertion hole, and at least one of the cutout portions which are located nearest to the long sides is formed as a first cutout portion where the cutout portion reaches to the long side.
    Type: Application
    Filed: April 30, 2007
    Publication date: November 15, 2007
    Inventors: Shinichi Utsumi, Takeyoshi Miyashita, Masaki Yokoyama
  • Publication number: 20070222313
    Abstract: A motor may include a bearing made of resin for rotatably supporting one end part of the rotor shaft, and an urging member attached to a bearing holder and abutted with a pressurization face of the bearing to urge the bearing toward a side of the rotor shaft. A molding material injection gate trace (projection) which has been used when the bearing is resin-molded is positioned at a center portion of the pressurization face. The molding material injection gate trace may be positioned in a recessed part which is formed at a roughly center portion of the pressurization face of the bearing. Further, the urging member may include an urging piece which is formed by cutting a center portion of a metal plate in a ring shape and an opening part is formed in the urging piece.
    Type: Application
    Filed: March 21, 2007
    Publication date: September 27, 2007
    Inventors: Hiroyuki Sonohara, Takeyoshi Miyashita