Patents by Inventor Toshimitsu Horiuchi

Toshimitsu Horiuchi 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: 7576947
    Abstract: A fluid dynamic pressure bearing device includes a first capillary seal (50) formed between an outer circumferential surface of a bearing member 20 and an internal circumferential surface of a seal member (30). A second capillary seal portion (60) is formed between an outer circumferential surface of a shaft member (10) and a protrusion hole (31) of the seal member (30). A ventilation hole (32a) is formed in a substantially intermediate portion of a side wall of the seal member. A lubricant holding gap (73) is formed between an inner surface of a top wall (31) of the seal member (30) and the upper end surface of the bearing member (20). Leakage of lubricant (80) is suppressed by action of the capillary seal portions (50, 60), and the liquid surface is positioned in the first capillary seal portion (50) above the ventilation hole (32a), whereby extra lubricant (80) is filled in the first capillary seal portion (50) and the lubricant holding gap (73).
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: August 18, 2009
    Assignee: Minebea Co., Ltd.
    Inventors: Fumiyasu Higuchi, Naoyuki Kondo, Toshimitsu Horiuchi
  • Publication number: 20090102300
    Abstract: The invention relates to a spindle motor for a hard disk drive comprising a baseplate (1), a shaft (2) fixedly connected to the baseplate (1), a thrust plate (3) fixedly connected to the free end of the shaft, a bearing bush (4) disposed about the shaft (2) and the thrust plate (3) and rotatably supported with respect to these components, a bearing gap (5) that is provided between the adjoining surfaces of the shaft (2), the bearing bush (4) and the thrust plate (3), at least one radial bearing (6; 7) formed by the adjoining surfaces of the shaft (2) and the bearing bush (4), an axial bearing (8) formed by the adjoining surfaces of the thrust plate (3) and the bearing bush (4), an annular rotor component (9) connected to the bearing bush (4), and an electromagnetic drive system having a rotor magnet (11) fixed to a rotating component and a stator arrangement (12) disposed on the baseplate (1) opposite the rotor magnet (11).
    Type: Application
    Filed: October 19, 2007
    Publication date: April 23, 2009
    Inventors: Thilo Rehm, Olaf Winterhalter, Hiroshi Yoshikawa, Toshimitsu Horiuchi
  • Publication number: 20080130168
    Abstract: A fluid dynamic pressure bearing device includes a first capillary seal (50) formed between an outer circumferential surface of a bearing member 20 and an internal circumferential surface of a seal member (30). A second capillary seal portion (60) is formed between an outer circumferential surface of a shaft member (10) and a protrusion hole (31) of the seal member (30). A ventilation hole (32a) is formed in a substantially intermediate portion of a side wall of the seal member. A lubricant holding gap (73) is formed between an inner surface of a top wall (31) of the seal member (30) and the upper end surface of the bearing member (20). Leakage of lubricant (80) is suppressed by action of the capillary seal portions (50, 60), and the liquid surface is positioned in the first capillary seal portion (50) above the ventilation hole (32a), whereby extra lubricant (80) is filled in the first capillary seal portion (50) and the lubricant holding gap (73).
    Type: Application
    Filed: November 30, 2005
    Publication date: June 5, 2008
    Applicant: Minebea Co., Ltd.
    Inventors: Fumiyasu Higuchi, Naoyuki Kondo, Toshimitsu Horiuchi
  • Patent number: 6998745
    Abstract: An apparatus for and a method of construction of a spindle motor having a bearing unit, a rotary shaft, a rotary hub member and an electro-magnetic motor is presented. The rotary shaft has a flange attached at a mid-section in an axial direction, between large and small diameter sections of the rotary shaft. Grooves between the bearing unit, rotary shaft and flange create radial dynamic pressure generating areas, each with as long as possible a span, and thrust dynamic pressure generating areas to both sides of the flange.
    Type: Grant
    Filed: March 10, 2003
    Date of Patent: February 14, 2006
    Assignee: Minebea Co., Ltd.
    Inventors: Toshimitsu Horiuchi, Andreas Kull
  • Publication number: 20030184175
    Abstract: An apparatus for and a method of construction of a spindle motor having a bearing unit, a rotary shaft, a rotary hub member and an electro-magnetic motor is presented. The rotary shaft has a flange attached at a mid-section in an axial direction, between large and small diameter sections of the rotary shaft. Grooves between the bearing unit, rotary shaft and flange create radial dynamic pressure generating areas, each with as long as possible a span, and thrust dynamic pressure generating areas to both sides of the flange.
    Type: Application
    Filed: March 10, 2003
    Publication date: October 2, 2003
    Applicant: Minebea Co., Ltd.
    Inventors: Toshimitsu Horiuchi, Andreas Kull