Patents by Inventor Atsushi Yawata

Atsushi Yawata 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).

  • Publication number: 20230077681
    Abstract: A motor includes a stator, a rotor, and a magnetic sensor. The stator includes an annular stator core. The stator core surrounds a central axis extending in an axial direction. The rotor is rotatable about the central axis. The rotor includes a first magnet, a second magnet, and a spacer. The first magnet is outward in a radial direction with respect to the stator core. The second magnet extends in one axial direction with respect to the first magnet and the stator core. The spacer is between the first magnet and the second magnet in the axial direction. The magnetic sensor detects a magnetic force of the second magnet. The spacer is made of a non-magnetic material.
    Type: Application
    Filed: September 9, 2022
    Publication date: March 16, 2023
    Inventors: Atsushi YAWATA, Yasuhiro UTSUNOMIYA
  • Patent number: 11460691
    Abstract: A motor includes a stationary unit and a rotation unit. The rotation unit includes a rotor hub, an annular body, and a clamp. The rotor hub is mounted with a first magnet opposite to the stator. The annular body is supported on an outer circumferential portion of the rotor hub. The clamp is directly or indirectly fixed to the rotor hub farther radially inside than the annular body, and presses the annular body to an axially lower side. The rotor hub includes a flange that expands radially outside from at least a portion excluding an upper end portion. On a surface of the clamp, a pattern to be detected to detect rotation of the rotation unit positioned in a circumferential direction with the central axis as the center is provided. The annular body is sandwiched between the flange and the clamp in an axial direction.
    Type: Grant
    Filed: February 10, 2020
    Date of Patent: October 4, 2022
    Assignee: NIDEC CORPORATION
    Inventor: Atsushi Yawata
  • Publication number: 20200301131
    Abstract: A motor includes a stationary unit and a rotation unit. The rotation unit includes a rotor hub, an annular body, and a clamp. The rotor hub is mounted with a first magnet opposite to the stator. The annular body is supported on an outer circumferential portion of the rotor hub. The clamp is directly or indirectly fixed to the rotor hub farther radially inside than the annular body, and presses the annular body to an axially lower side. The rotor hub includes a flange that expands radially outside from at least a portion excluding an upper end portion. On a surface of the clamp, a pattern to be detected to detect rotation of the rotation unit positioned in a circumferential direction with the central axis as the center is provided. The annular body is sandwiched between the flange and the clamp in an axial direction.
    Type: Application
    Filed: February 10, 2020
    Publication date: September 24, 2020
    Inventor: Atsushi YAWATA
  • Patent number: 10622015
    Abstract: A hollow shaft includes a hollow portion extending in an axial direction from an opening that is open at one end of the hollow shaft in the axial direction. The hollow shaft further includes a first communicating hole establishing radial communication between the hollow portion and an axial space between an upper lubricating oil and a lower lubricating oil. The hollow shaft further includes a second communicating hole establishing radial communication between the hollow portion and an unsealed space inside the motor. The unsealed space is connected to an external space outside the motor. The hollow shaft further includes a sealing member closing the opening. The hollow shaft has, in an inner peripheral surface facing the hollow portion, a recess recessed radially outward. A part of the sealing member is fitted into the recess.
    Type: Grant
    Filed: October 30, 2018
    Date of Patent: April 14, 2020
    Assignee: NIDEC CORPORATION
    Inventor: Atsushi Yawata
  • Publication number: 20190165637
    Abstract: A hollow shaft includes a hollow portion extending in an axial direction from an opening that is open at one end of the hollow shaft in the axial direction. The hollow shaft further includes a first communicating hole establishing radial communication between the hollow portion and an axial space between an upper lubricating oil and a lower lubricating oil. The hollow shaft further includes a second communicating hole establishing radial communication between the hollow portion and an unsealed space inside the motor. The unsealed space is connected to an external space outside the motor. The hollow shaft further includes a sealing member closing the opening. The hollow shaft has, in an inner peripheral surface facing the hollow portion, a recess recessed radially outward. A part of the sealing member is fitted into the recess.
    Type: Application
    Filed: October 30, 2018
    Publication date: May 30, 2019
    Inventor: Atsushi YAWATA
  • Patent number: 9739312
    Abstract: A bearing mechanism includes a stationary portion and a rotating portion. The stationary portion includes a shaft portion and a plate portion. The rotating portion includes a sleeve including an annular portion, a cylindrical portion, an annular bottom surface, and a first communication hole. The rotating portion includes a ring member arranged to cover at least a portion of an opening of the first communication hole, and faces the plate portion via a first gap. A pumping groove array is disposed in the plate portion or the ring member. A second communication hole is disposed between the ring member and the annular bottom surface, and connected to the first communication hole. At least a portion of the opening of the second communication hole is positioned on a farther radial direction inner side than the pumping groove array.
    Type: Grant
    Filed: August 13, 2014
    Date of Patent: August 22, 2017
    Assignee: NIDEC CORPORATION
    Inventors: Hirotoshi Uchibori, Toshihiro Akiyama, Atsushi Yawata
  • Patent number: 9613650
    Abstract: A method of manufacturing a base unit of a spindle motor includes the steps of: defining a base plate including a support fitting portion; fitting a support to a hole portion passing through the support fitting portion; measuring an inclination of the support fitting portion; calculating a laser irradiation area and a laser irradiation output based on the inclination; irradiating the support fitting portion with a laser beam; and measuring the inclination of the support fitting portion again. The base plate is made of a metal, and is defined by press working, casting, or forging. The support is fitted to the hole portion by crimping, press fitting, or welding. This method reduces the inclination of the support fitting portion, thereby reducing a distortion of the support, which serves as a rotation center of an access portion.
    Type: Grant
    Filed: September 24, 2015
    Date of Patent: April 4, 2017
    Assignee: NIDEC CORPORATION
    Inventors: Atsushi Yawata, Shigeki Horiki, Ryohei Matsumoto
  • Patent number: 9520754
    Abstract: A motor for use in a disk drive apparatus includes a bearing, a rotary unit, a stator, a thin flat base member, and a cylindrical holder extending in an axial direction. The base member includes a first through-hole, a peripheral edge portion, and a thin portion. The thin portion is located radially outward of the peripheral edge portion. The thin portion has an axial thickness smaller than an axial thickness of the peripheral edge portion. The holder includes a first protrusion portion and a second protrusion portion. The first protrusion portion extends radially outward and is located axially above the peripheral edge portion. The second protrusion portion extends radially outward and is located axially below the peripheral edge portion. The bearing is located inside the holder. A stator core is located radially outside the holder and axially above the thin portion.
    Type: Grant
    Filed: March 20, 2014
    Date of Patent: December 13, 2016
    Assignee: NIDEC CORPORATION
    Inventors: Takuro Matsumoto, Atsushi Yawata
  • Publication number: 20160163349
    Abstract: A method of manufacturing a base unit of a spindle motor includes the steps of: defining a base plate including a support fitting portion; fitting a support to a hole portion passing through the support fitting portion; measuring an inclination of the support fitting portion; calculating a laser irradiation area and a laser irradiation output based on the inclination; irradiating the support fitting portion with a laser beam; and measuring the inclination of the support fitting portion again. The base plate is made of a metal, and is defined by press working, casting, or forging. The support is fitted to the hole portion by crimping, press fitting, or welding. This method reduces the inclination of the support fitting portion, thereby reducing a distortion of the support, which serves as a rotation center of an access portion.
    Type: Application
    Filed: September 24, 2015
    Publication date: June 9, 2016
    Inventors: Atsushi YAWATA, Shigeki HORIKI, Ryohei MATSUMOTO
  • Patent number: 9165594
    Abstract: A spindle motor includes a stationary portion with a shaft, a circular plate portion, a wall portion, and a plate portion. The plate portion has a flat plate portion and an annular convex portion. The sleeve includes an annular portion, an outer side cylindrical portion, and an inner side cylindrical portion. The inner side cylindrical portion and an upper radial dynamic pressure groove array are superimposed in a radial direction. The upper radial dynamic pressure groove array includes a plurality of upper spiral grooves that is inclined in one direction with respect to an axial direction and a plurality of lower spiral grooves that is inclined in another direction opposite to the one direction. A lower end of the upper spiral grooves is positioned farther on an upper side than an upper surface of the annular portion.
    Type: Grant
    Filed: August 13, 2014
    Date of Patent: October 20, 2015
    Assignee: Nidec Corporation
    Inventors: Atsushi Yawata, Hirotoshi Uchibori, Toshihiro Akiyama
  • Patent number: 9166452
    Abstract: A spindle motor includes a base portion, a stationary portion, and a circuit substrate disposed in the base portion. The base portion includes a flat plate portion positioned below the rotary portion and a through-hole extending from an upper surface to a lower surface of the flat plate portion. The flat plate portion includes a first surface positioned between the upper surface and the lower surface of the flat plate portion and disposed within the through-hole. The circuit substrate includes a land portion to which a lead wire extending from a plurality of coils is electrically connected. The land portion is disposed on the first surface. The lead wire is connected to the land portion by solder within the through-hole.
    Type: Grant
    Filed: March 6, 2015
    Date of Patent: October 20, 2015
    Assignee: Nidec Corporation
    Inventors: Takashi Endo, Atsushi Yawata
  • Patent number: 9001461
    Abstract: A spindle motor includes a stationary portion and a rotating portion. The stationary portion includes a shaft and the rotating portion includes a sleeve portion, a hub, a magnet, and a cap. The sleeve portion is arranged opposite to the shaft. The hub is made of metal, and includes a top plate portion extending radially outward from the sleeve portion, and an outer tubular portion extending downward from an outer edge of the top plate portion. The magnet is fixed to the outer tubular portion and is arranged opposite to the stator. The cap is made of metal, and includes an annular plate-shaped portion fixed to an upper surface of the top plate portion. The magnet has a coefficient of thermal expansion greater than that of the hub. The cap has a coefficient of thermal expansion greater than that of both the hub and the magnet.
    Type: Grant
    Filed: August 13, 2014
    Date of Patent: April 7, 2015
    Assignee: Nidec Corporation
    Inventor: Atsushi Yawata
  • Publication number: 20150085398
    Abstract: A spindle motor includes a stationary portion with a shaft, a circular plate portion, a wall portion, and a plate portion. The plate portion has a flat plate portion and an annular convex portion. The sleeve includes an annular portion, an outer side cylindrical portion, and an inner side cylindrical portion. The inner side cylindrical portion and an upper radial dynamic pressure groove array are superimposed in a radial direction. The upper radial dynamic pressure groove array includes a plurality of upper spiral grooves that is inclined in one direction with respect to an axial direction and a plurality of lower spiral grooves that is inclined in another direction opposite to the one direction. A lower end of the upper spiral grooves is positioned farther on an upper side than an upper surface of the annular portion.
    Type: Application
    Filed: August 13, 2014
    Publication date: March 26, 2015
    Inventors: Atsushi YAWATA, Hirotoshi UCHIBORI, Toshihiro AKIYAMA
  • Publication number: 20150085397
    Abstract: A spindle motor includes a stationary portion and a rotating portion. The stationary portion includes a shaft and the rotating portion includes a sleeve portion, a hub, a magnet, and a cap. The sleeve portion is arranged opposite to the shaft. The hub is made of metal, and includes a top plate portion extending radially outward from the sleeve portion, and an outer tubular portion extending downward from an outer edge of the top plate portion. The magnet is fixed to the outer tubular portion and is arranged opposite to the stator. The cap is made of metal, and includes an annular plate-shaped portion fixed to an upper surface of the top plate portion. The magnet has a coefficient of thermal expansion greater than that of the hub. The cap has a coefficient of thermal expansion greater than that of both the hub and the magnet.
    Type: Application
    Filed: August 13, 2014
    Publication date: March 26, 2015
    Inventor: Atsushi YAWATA
  • Publication number: 20150084463
    Abstract: A bearing mechanism includes a stationary portion and a rotating portion. The stationary portion includes a shaft portion and a plate portion. The rotating portion includes a sleeve including an annular portion, a cylindrical portion, an annular bottom surface, and a first communication hole. The rotating portion includes a ring member arranged to cover at least a portion of an opening of the first communication hole, and faces the plate portion via a first gap. A pumping groove array is disposed in the plate portion or the ring member. A second communication hole is disposed between the ring member and the annular bottom surface, and connected to the first communication hole. At least a portion of the opening of the second communication hole is positioned on a farther radial direction inner side than the pumping groove array.
    Type: Application
    Filed: August 13, 2014
    Publication date: March 26, 2015
    Inventors: Hirotoshi UCHIBORI, Toshihiro AKIYAMA, Atsushi YAWATA
  • Patent number: 8922945
    Abstract: A spindle motor includes a stationary unit, a rotary unit and a bearing mechanism. The stationary unit includes a base member, a stator including a plurality of coils and a wiring substrate electrically connected to the stator. The base member includes a tubular portion, a first accommodation portion, an opening portion, a plurality of coil accommodation portions, a second accommodation portion, and at least one through-hole. The wiring substrate includes an arc portion and an extension portion. A lead wire is led out from at least one of the coils and is connected to the arc portion by soldering within the through-hole.
    Type: Grant
    Filed: February 14, 2013
    Date of Patent: December 30, 2014
    Assignee: Nidec Corporation
    Inventors: Shintaro Saeki, Atsushi Yawata, Yoichi Sekii, Takehito Tamaoka, Hiroyuki Abe
  • Patent number: 8824096
    Abstract: A rotating portion of a motor includes a hub body portion and a shaft arranged to extend in an axial direction. The hub body portion includes a through hole and a recessed portion. The recessed portion extends radially outward from an outside surface of the shaft, has an annular shape and is recessed axially downward. The recessed portion includes first, second, and third ridge portions. The first ridge portion is an axially upper edge of an inside surface defining the through hole, the second ridge portion is arranged radially outward of the first ridge portion, and the third ridge portion is arranged radially outward of the second ridge portion, and is located axially above both the first ridge portion and the second ridge portion. An adhesive is arranged to cover the outside surface of the shaft and reach a portion of the second ridge portion.
    Type: Grant
    Filed: February 5, 2014
    Date of Patent: September 2, 2014
    Assignee: Nidec Corporation
    Inventors: Toshihiro Akiyama, Atsushi Yawata
  • Publication number: 20140203691
    Abstract: A motor for use in a disk drive apparatus includes a bearing, a rotary unit, a stator, a thin flat base member, and a cylindrical holder extending in an axial direction. The base member includes a first through-hole, a peripheral edge portion, and a thin portion. The thin portion is located radially outward of the peripheral edge portion. The thin portion has an axial thickness smaller than an axial thickness of the peripheral edge portion. The holder includes a first protrusion portion and a second protrusion portion. The first protrusion portion extends radially outward and is located axially above the peripheral edge portion. The second protrusion portion extends radially outward and is located axially below the peripheral edge portion. The bearing is located inside the holder. A stator core is located radially outside the holder and axially above the thin portion.
    Type: Application
    Filed: March 20, 2014
    Publication date: July 24, 2014
    Applicant: NIDEC CORPORATION
    Inventors: Takuro MATSUMOTO, Atsushi YAWATA
  • Patent number: 8755145
    Abstract: A base unit includes a stator and a base member including a first recess portion, a second recess portion, and at least one through-hole. The first recess portion is arranged on an upper surface of the base member to surround the hole portion and depressed toward the lower surface thereof. The second recess portion is arranged radially outward of the first recess portion and depressed toward a lower surface thereof. The through-hole is arranged inside the first recess portion to extend through the base member. The second recess portion includes a protrusion portion and a third recess portion. The protrusion portion protrudes from the lower surface of the base member toward the upper surface of the base member. The third recess portion is depressed from the lower surface of the base member toward the upper surface of the base member and positioned at the opposite side from the protrusion portion.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: June 17, 2014
    Assignee: Nidec Corporation
    Inventors: Takuro Matsumoto, Toshihiro Akiyama, Atsushi Yawata
  • Patent number: 8711515
    Abstract: A motor includes a stator and a rotor including a disk portion, a cylindrical portion, and a stopper. The stopper includes a stopper protruding portion and is fixed to an inner surface of the cylindrical portion. The cylindrical portion includes a cylindrical portion protruding portion that opposes an outer surface of the stopper. Adhesive is included between the cylindrical portion and the stopper. A gap between an upper end portion of the outer surface of the stopper and an inner peripheral surface of the cylindrical portion protruding portion defines a first tapered gap. A gap between a lower end portion of the outer surface of the stopper and an inner peripheral surface of the cylindrical portion defines a second tapered gap. The adhesive is included in the first tapered gap and the second tapered gap. The stator includes an annular or substantially annular surface below the second tapered gap.
    Type: Grant
    Filed: February 14, 2013
    Date of Patent: April 29, 2014
    Assignee: Nidec Corporation
    Inventors: Shintaro Saeki, Atsushi Yawata