Patents by Inventor Kunio Sakurada

Kunio Sakurada 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: 11002312
    Abstract: In an aerodynamic bearing, an outer peripheral surface of a shaft and an inner peripheral surface of a sleeve face each other in a radial direction. The sleeve includes a through hole penetrating the sleeve in the radial direction. A space on a radially inner side of the sleeve communicates with an external space of a motor through the through hole. A stationary portion includes a wall portion radially overlapping the through hole with a gap interposed therebetween on a radially outer side of the through hole.
    Type: Grant
    Filed: March 6, 2019
    Date of Patent: May 11, 2021
    Assignee: NIDEC CORPORATION
    Inventors: Hiroshi Morishita, Kunio Sakurada, Hirotaka Tamekuni, Takeru Omura
  • Patent number: 10920787
    Abstract: A blower includes an impeller that is rotatable about a central axis extending in a vertical direction, a motor that rotates the impeller, and a base portion on which the motor is mounted. The impeller includes a cup portion that covers the motor, and blades extending radially outward from the cup portion and arranged in a circumferential direction. A gap is provided between the cup portion and the base portion such that the gap becomes narrower in an outward direction with increasing distance from an interior of the cup portion.
    Type: Grant
    Filed: October 11, 2018
    Date of Patent: February 16, 2021
    Assignee: NIDEC CORPORATION
    Inventors: Kunio Sakurada, Hiroshi Morishita, Akinobu Sumiji, Hirotaka Tamekuni
  • Patent number: 10590989
    Abstract: A bearing apparatus includes a cylindrical sleeve, a shaft rotatably inserted in the sleeve, lubricating oil arranged in a gap defined between an inner circumferential surface of the sleeve and an outer circumferential surface of the shaft, a seal member arranged at an axially upper end portion of the sleeve projecting from the sleeve, and an annular member fixed to an outer circumferential surface of the axially upper end portion of the shaft to rotate together with the shaft. The annular member includes a projecting portion projecting axially downward. The seal member and an axially lower end portion of the projecting portion overlap each other when viewed in at least one of the axial direction or a radial direction.
    Type: Grant
    Filed: August 31, 2018
    Date of Patent: March 17, 2020
    Assignee: NIDEC CORPORATION
    Inventors: Kunio Sakurada, Akinobu Sumiji, Akihiro Yudate, Sho Nakamura
  • Publication number: 20190285116
    Abstract: In an aerodynamic bearing, an outer peripheral surface of a shaft and an inner peripheral surface of a sleeve face each other in a radial direction. The sleeve includes a through hole penetrating the sleeve in the radial direction. A space on a radially inner side of the sleeve communicates with an external space of a motor through the through hole. A stationary portion includes a wall portion radially overlapping the through hole with a gap interposed therebetween on a radially outer side of the through hole.
    Type: Application
    Filed: March 6, 2019
    Publication date: September 19, 2019
    Inventors: Hiroshi MORISHITA, Kunio SAKURADA, Hirotaka TAMEKUNI, Takeru OMURA
  • Patent number: 10407775
    Abstract: A base plate is arranged to define a portion of a housing of a hard disk drive, and includes a base body defined by casting, and an electrodeposition coating film arranged to cover a surface of the base body. The surface of the base body includes a coated surface covered with the electrodeposition coating film, and a flat worked surface exposed from the electrodeposition coating film. The worked surface may include a gate position to which a gate has been connected at the time of the casting. At least a portion of the worked surface is covered with an impregnant.
    Type: Grant
    Filed: January 25, 2018
    Date of Patent: September 10, 2019
    Assignee: NIDEC CORPORATION
    Inventors: Kunio Sakurada, Tomohiro Yoneda
  • Publication number: 20190195232
    Abstract: A blower includes an impeller that is rotatable about a central axis extending in a vertical direction, a motor that rotates the impeller, and a base portion on which the motor is mounted. The impeller includes a cup portion that covers the motor, and blades extending radially outward from the cup portion and arranged in a circumferential direction. A gap is provided between the cup portion and the base portion such that the gap becomes narrower in an outward direction with increasing distance from an interior of the cup portion.
    Type: Application
    Filed: October 11, 2018
    Publication date: June 27, 2019
    Inventors: Kunio SAKURADA, Hiroshi MORISHITA, Akinobu SUMIJI, Hirotaka TAMEKUNI
  • Publication number: 20190093705
    Abstract: A bearing apparatus includes a cylindrical sleeve, a shaft rotatably inserted in the sleeve, lubricating oil arranged in a gap defined between an inner circumferential surface of the sleeve and an outer circumferential surface of the shaft, a seal member arranged at an axially upper end portion of the sleeve projecting from the sleeve, and an annular member fixed to an outer circumferential surface of the axially upper end portion of the shaft to rotate together with the shaft. The annular member includes a projecting portion projecting axially downward. The seal member and an axially lower end portion of the projecting portion overlap each other when viewed in at least one of the axial direction or a radial direction.
    Type: Application
    Filed: August 31, 2018
    Publication date: March 28, 2019
    Inventors: Kunio SAKURADA, Akinobu SUMIJI, Akihiro YUDATE, Sho NAKAMURA
  • Publication number: 20190093234
    Abstract: A base plate is arranged to define a portion of a housing of a hard disk drive, and includes a base body defined by casting, and an electrodeposition coating film arranged to cover a surface of the base body. The surface of the base body includes a coated surface covered with the electrodeposition coating film, and a flat worked surface exposed from the electrodeposition coating film. The worked surface may include a gate position to which a gate has been connected at the time of the casting. At least a portion of the worked surface is covered with an impregnant.
    Type: Application
    Filed: January 25, 2018
    Publication date: March 28, 2019
    Inventors: Kunio Sakurada, Tomohiro Yoneda
  • Patent number: 8967865
    Abstract: A bearing apparatus includes a first cup portion defining a portion of a stationary portion of a bearing apparatus includes a first circular plate portion and a first cylindrical portion projecting downward from an outer edge portion of the first circular plate portion. A rotating portion of the bearing apparatus includes an annular recessed portion arranged to accommodate at least a lower end portion of the first cylindrical portion. The stationary portion includes a second cup portion including a second circular plate portion arranged to extend radially outward from an outer circumferential surface of a stationary shaft below the first cup portion and a second cylindrical portion arranged to project upward from an outer edge portion of the second circular plate portion. One of the first and second cup portions is integral with the stationary shaft defining a single monolithic member, and the other is fixed to the stationary shaft.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: March 3, 2015
    Assignee: Nidec Corporation
    Inventors: Akihiro Kimura, Teiichi Hirono, Kunio Sakurada, Kyoko Horise
  • Patent number: 8794839
    Abstract: A bearing apparatus includes a stationary shaft, a first annular member, and a rotating member. The rotating member includes a first inner circumferential surface arranged opposite to the outer circumferential surface of the stationary shaft, and a second inner circumferential surface arranged opposite to an outer circumferential surface of the first annular member. A lubricating oil is arranged in a gap between a surface of a stationary member and the rotating member. On an upper side of an upper surface of the lubricating oil, the first annular member and the rotating member are arranged radially opposite to each other with a slight gap defined therebetween, so that a labyrinth seal is defined. The labyrinth seal and a fixing range over which the stationary shaft and the first annular member are fixed to each other are arranged to overlap with each other in a radial direction.
    Type: Grant
    Filed: September 4, 2012
    Date of Patent: August 5, 2014
    Assignee: Nidec Corporation
    Inventors: Akihiro Kimura, Teiichi Hirono, Kunio Sakurada, Kyoko Horise, Takehito Tamaoka, Kazuhiro Sato, Yoichi Sekii
  • Patent number: 8690435
    Abstract: A dynamic pressure bearing has a reduced axial dimension and is constructed to ensure smooth feeding of a lubricating oil. The dynamic pressure bearing includes a communicating hole and at least one tapered seal, and is constructed such that an opening angle of one of the at least one tapered seal through which oil feeding is possible is in a range of about 30 degrees inclusive to about 180 degrees exclusive, a tapered seal wall surface depth W1 of the tapered seal is about 0.3 mm or more, and a sum of distances over which the lubricating oil travels from both sides of an end portion of the communicating hole in a cross-section beyond a wall surface of the communicating hole along a wall surface opposite the end portion of the communicating hole exceeds an inside diameter of the communicating hole.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: April 8, 2014
    Assignee: Nidec Corporation
    Inventors: Akihiro Kimura, Kyoko Horise, Ryota Ogino, Kunio Sakurada, Teiichi Hirono
  • Patent number: 8630063
    Abstract: A bearing mechanism includes a shaft portion, a sleeve portion, a lower opposing portion, a lower outer annular portion, and an upper opposing portion. The sleeve portion includes a sleeve body and a lower thrust plate. A radial dynamic pressure bearing portion is defined in a radial gap. A lower thrust dynamic pressure bearing portion is defined in a lower thrust gap. A lower seal portion is defined in a lower seal gap located between the sleeve portion and the lower outer annular portion. An upper seal portion is defined in an upper seal gap continuous with an upper thrust gap. The sleeve portion includes a first communicating channel in communication with the upper seal gap, and a second communicating channel located between the sleeve body and the lower thrust plate. A lower mouth portion of the first communicating channel axially overlaps the lower thrust dynamic pressure bearing portion.
    Type: Grant
    Filed: February 25, 2013
    Date of Patent: January 14, 2014
    Assignee: Nidec Corporation
    Inventors: Akinobu Sumiji, Akihiro Kimura, Kunio Sakurada
  • Publication number: 20140010065
    Abstract: A bearing apparatus includes a first cup portion defining a portion of a stationary portion of a bearing apparatus includes a first circular plate portion and a first cylindrical portion projecting downward from an outer edge portion of the first circular plate portion. A rotating portion of the bearing apparatus includes an annular recessed portion arranged to accommodate at least a lower end portion of the first cylindrical portion. The stationary portion includes a second cup portion including a second circular plate portion arranged to extend radially outward from an outer circumferential surface of a stationary shaft below the first cup portion and a second cylindrical portion arranged to project upward from an outer edge portion of the second circular plate portion. One of the first and second cup portions is integral with the stationary shaft defining a single monolithic member, and the other is fixed to the stationary shaft.
    Type: Application
    Filed: September 12, 2013
    Publication date: January 9, 2014
    Applicant: NIDEC CORPORATION
    Inventors: Akihiro KIMURA, Teiichi HIRONO, Kunio SAKURADA, Kyoko HORISE
  • Patent number: 8613553
    Abstract: A fluid dynamic bearing includes: a shaft arranged along a center axis; an annular portion expanding radially outwards from the shaft; a sleeve having a top surface opposed to an under surface of the annular portion to support the shaft and the annular portion in a relatively rotatable manner; and a lubricating fluid interposed between the shaft and annular portion and the sleeve. The fluid dynamic bearing further includes a substantially annular edge surrounding the center axis on the under surface and a solid lubricating film on the radially outer side of the edge.
    Type: Grant
    Filed: July 20, 2010
    Date of Patent: December 24, 2013
    Assignee: Nidec Corporation
    Inventors: Manabu Komori, Mitsuya Kusuhara, Kunio Sakurada, Kazuya Sato
  • Publication number: 20130321952
    Abstract: A bearing mechanism includes a shaft portion, a sleeve portion, a lower opposing portion, a lower outer ring-shaped portion, and an upper opposing portion. A lower seal portion serving as a pumping seal portion is provided in a lower seal gap between the sleeve portion and the lower outer ring-shaped portion. An upper seal portion is provided in an upper seal gap joined to an upper thrust gap. The lower portion of the sleeve portion includes a large-diameter portion and a small-diameter portion positioned below the large-diameter portion. The sleeve portion includes a communication path joined to the upper seal gap. The communication path includes an opening portion opened in a border between the large-diameter portion and the small-diameter portion. The outer peripheral portion of the lower opposing portion includes an outer periphery protrusion portion radially opposed to the small-diameter portion and axially opposed to the large-diameter portion.
    Type: Application
    Filed: March 5, 2013
    Publication date: December 5, 2013
    Applicant: NIDEC CORPORATION
    Inventors: Akinobu SUMIJI, Akihiro KIMURA, Kunio SAKURADA
  • Publication number: 20130321946
    Abstract: A bearing mechanism includes a shaft portion, a sleeve portion, and an opposing portion including a surface arranged opposite to an end surface of the sleeve portion on one of upper and lower sides with a thrust gap defined therebetween. The thrust gap includes a thrust dynamic pressure bearing portion defined therein. The sleeve portion includes a sleeve body and a thrust plate fixed to an end portion of the sleeve body on the one of the upper and lower sides. The sleeve body includes an annular surface arranged opposite to the thrust plate, and an annular body projecting portion arranged to project in an axial direction inside of the annular surface. An outer circumferential surface of the body projecting portion and an inner circumferential surface of the thrust plate are arranged to be in direct or indirect contact with each other.
    Type: Application
    Filed: February 25, 2013
    Publication date: December 5, 2013
    Applicant: NIDEC CORPORATION
    Inventors: Akihiro KIMURA, Akinobu SUMIJI, Kunio SAKURADA, Daisuke FUKUOKA, Akihisa MORIGUCHI
  • Publication number: 20130321951
    Abstract: A bearing mechanism includes a shaft portion, a sleeve portion, a lower opposing portion, a lower outer annular portion, and an upper opposing portion. The sleeve portion includes a sleeve body and a lower thrust plate. A radial dynamic pressure bearing portion is defined in a radial gap. A lower thrust dynamic pressure bearing portion is defined in a lower thrust gap. A lower seal portion is defined in a lower seal gap located between the sleeve portion and the lower outer annular portion. An upper seal portion is defined in an upper seal gap continuous with an upper thrust gap. The sleeve portion includes a first communicating channel in communication with the upper seal gap, and a second communicating channel located between the sleeve body and the lower thrust plate. A lower mouth portion of the first communicating channel axially overlaps the lower thrust dynamic pressure bearing portion.
    Type: Application
    Filed: February 25, 2013
    Publication date: December 5, 2013
    Applicant: NIDEC CORPORATION
    Inventors: Akinobu SUMIJI, Akihiro KIMURA, Kunio SAKURADA
  • Patent number: 8599513
    Abstract: A bearing mechanism includes a shaft portion, a sleeve portion, and an opposing portion including a surface arranged opposite to an end surface of the sleeve portion on one of upper and lower sides with a thrust gap defined therebetween. The thrust gap includes a thrust dynamic pressure bearing portion defined therein. The sleeve portion includes a sleeve body and a thrust plate fixed to an end portion of the sleeve body on the one of the upper and lower sides. The sleeve body includes an annular surface arranged opposite to the thrust plate, and an annular body projecting portion arranged to project in an axial direction inside of the annular surface. An outer circumferential surface of the body projecting portion and an inner circumferential surface of the thrust plate are arranged to be in direct or indirect contact with each other.
    Type: Grant
    Filed: February 25, 2013
    Date of Patent: December 3, 2013
    Assignee: Nidec Corporation
    Inventors: Akihiro Kimura, Akinobu Sumiji, Kunio Sakurada, Daisuke Fukuoka, Akihisa Moriguchi
  • Patent number: 8587895
    Abstract: A bearing mechanism includes a shaft portion, a sleeve portion, a lower opposing portion, a lower outer ring-shaped portion, and an upper opposing portion. A lower seal portion serving as a pumping seal portion is provided in a lower seal gap between the sleeve portion and the lower outer ring-shaped portion. An upper seal portion is provided in an upper seal gap joined to an upper thrust gap. The lower portion of the sleeve portion includes a large-diameter portion and a small-diameter portion positioned below the large-diameter portion. The sleeve portion includes a communication path joined to the upper seal gap. The communication path includes an opening portion opened in a border between the large-diameter portion and the small-diameter portion. The outer peripheral portion of the lower opposing portion includes an outer periphery protrusion portion radially opposed to the small-diameter portion and axially opposed to the large-diameter portion.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: November 19, 2013
    Assignee: Nidec Corporation
    Inventors: Akinobu Sumiji, Akihiro Kimura, Kunio Sakurada
  • Patent number: 8568033
    Abstract: In a bearing apparatus, a first cup portion defining a portion of a stationary portion of a bearing apparatus includes a circular plate portion and a cylindrical portion projecting downward from an outer edge portion of the circular plate portion. A rotating portion of the bearing apparatus includes an annular recessed portion arranged to accommodate at least a lower end portion of the cylindrical portion. Accordingly, it is possible to limit the axial dimension of the bearing apparatus while also enabling a radial dynamic pressure groove array. Additionally, one end of a through hole defined in the rotating portion is arranged to open into the annular recessed portion.
    Type: Grant
    Filed: September 4, 2012
    Date of Patent: October 29, 2013
    Assignee: Nidec Corporation
    Inventors: Akihiro Kimura, Teiichi Hirono, Kunio Sakurada, Kyoko Horise