Patents by Inventor Mutsuro Ohta

Mutsuro Ohta 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: 6532137
    Abstract: A disk drive head assembly enables adjustment of a center of gravity of the head assembly of a depopulation version, while suppressing an occurrence of a resonance frequency affecting the performance of the disk drive apparatus. The head assembly for the data storage media includes: magnetic heads for reading/writing data from/to the data storage media, arms to which the magnetic heads are attached, a pivot shaft holder for supporting the arms, a coil for a voice coil motor extended from the pivot shaft holder, and a counter weight provided at a predetermined position opposite to a coil for the voice coil motor with respect to the pivot shaft holder.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: March 11, 2003
    Assignee: International Business Machines Corporation
    Inventors: Fu-Ying Huang, Mutsuro Ohta, Keishi Takahashi, Kohichi Takeuchi
  • Patent number: 6507461
    Abstract: An inertial latch for preventing an actuator arm, which is a component of a disk apparatus, from flying out from an unloading position because of an external shock. The actuator arm cannot be prevented from flying out from the unloading position because of repulsion produced when the actuator arm crashes against a stopper, by operation other than an external shock. A latch, for engaging with a point end portion of the actuator arm to prevent the actuator arm from flying out, is provided with a sensing protrusion 16e. When the actuator arm crashes against an outer crash stop, the shock causes the latch to rotate and engage with the actuator arm, whereby the actuator arm is prevented from flying out.
    Type: Grant
    Filed: November 20, 2001
    Date of Patent: January 14, 2003
    Assignee: International Business Machines Corporation
    Inventors: Shinichi Kimura, Jun Ishikawa, Kohji Takahashi, Mutsuro Ohta
  • Publication number: 20020105754
    Abstract: A disk drive apparatus and method applicable therein for reducing disk flutter and the negative effects thereof. The apparatus of the present invention includes a hard disk drive unit including a motor that rotatably drives multiple disk data storage media. The hard disk drive unit further includes a disk assembly in which the disk storage media are disposed coaxially in sequence with predetermined spaces from the motor, wherein a space between axially centered disk storage media within the multiple disk storage media is set greater than the other spaces between disk storage media.
    Type: Application
    Filed: September 7, 2001
    Publication date: August 8, 2002
    Inventors: Dale C. Goeke, Mutsuro Ohta, Koichi Takeuchi, Shingo Tsuda
  • Publication number: 20020063999
    Abstract: A disk drive head assembly enables adjustment of a center of gravity of the head assembly of a depopulation version, while suppressing an occurrence of a resonance frequency affecting the performance of the disk drive apparatus. The head assembly for the data storage media includes: magnetic heads for reading/writing data from/to the data storage media, arms to which the magnetic heads are attached, a pivot shaft holder for supporting the arms, a coil for a voice coil motor extended from the pivot shaft holder, and a counter weight provided at a predetermined position opposite to a coil for the voice coil motor with respect to the pivot shaft holder.
    Type: Application
    Filed: November 28, 2001
    Publication date: May 30, 2002
    Applicant: International Business Machines Corporation
    Inventors: Fu-Ying Huang, Mutsuro Ohta, Keishi Takahashi, Kohichi Takeuchi
  • Publication number: 20020044375
    Abstract: A hard disk drive apparatus is capable of reducing a noise effectively during operation and capable of enhancing the reliability of the drive. The hard disk drive has first and second ribs that are formed near a pivot for an actuator so that a tilt of the pivot is prevented when the actuator is operated. Also, vibration absorbing members are interposed between the first and second ribs on the side of a base and a cover so that the vibration absorbing members are brought into contact with the cover. These vibration absorbing members are located in an intermediate portion between fixing places for fixing the cover to the base and a fixing place for fixing the cover to the pivot.
    Type: Application
    Filed: October 5, 2001
    Publication date: April 18, 2002
    Applicant: International Business Machines Corporation
    Inventors: Yoshihiro Hirasaka, Keishi Takahasi, Kohji Serizawa, Mutsuro Ohta
  • Publication number: 20020021521
    Abstract: A magnetic circuit is provided in an enclosure that can efficiently generate magnetic flux from the enclosure, configuring a magnetic disk, to a magnetic disk. Thus, by providing such a magnetic circuit, a magnetic field different from that in other enclosure parts, that is, a local magnetic field, is generated from the magnetic circuit in case the disk device is set in an external magnetic field. Hence, this local magnetic field can effectively erase data in the magnetic disk. In particular, since the local magnetic field is generated even if the external magnetic field is weak, it is possible to not only suppress the demagnetization of permanent magnets used in the spindle motor at minimum, but also effectively erase data in the magnetic disk.
    Type: Application
    Filed: April 4, 2001
    Publication date: February 21, 2002
    Applicant: International Business Machines Corporation
    Inventors: Hiroki Kitahori, Kenji Kuroki, Hiroshi Matsuda, Satoshi Noguchi, Mutsuro Ohta, Keishi Takahashi, Hitoshi Tamura
  • Publication number: 20010015875
    Abstract: The present invention provides a depopulation version hard disk drive apparatus that has a reduced number of magnetic heads and suspension arms from a standard hard disk drive apparatus, wherein the magnetic head can still be properly controlled during a loading state. The hard disk drive apparatus includes a ramp which interfaces with the suspension arm when loading and unloading the arm. An angle of a second slope surface 61c of the ramp in the depopulation version hard disk drive is set larger than that of the corresponding slope surface of the ramp 6 the a standard version hard disk drive.
    Type: Application
    Filed: February 21, 2001
    Publication date: August 23, 2001
    Applicant: International Business Machines Corporation
    Inventors: Mutsuro Ohta, Hiroshi Matsuda, Takahide Nakamura, Keishi Takahashi
  • Patent number: 6137658
    Abstract: An apparatus to guide and lock a rotary actuator at a limiting rotational angle in a disk storage. A rotary actuator is attached within a housing so that it is rotatable on a pivot shaft. An iron piece is rotated integrally with the rotary actuator and is attracted in magnetic cooperation with a lock magnet. A retract magnet is attached to housing and assists in rotation of the actuator during an unload operation in which the rotary actuator is removed to a load/unload ramp.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: October 24, 2000
    Assignee: International Business Machines Corporation
    Inventors: Shinichi Matsuzaki, Kohji Serizawa, Mutsuro Ohta, Keishi Takahashi
  • Patent number: 6034843
    Abstract: The present invention provides a stacked type actuator arm assembly equipped with a structure for easily fixing lead wires between a coil and a flexible cable. A stacked type actuator arm assembly that is used in a magnetic disk storage is equipped at the coil support portion of a coil support spacer with a small hole through which lead wires and are inserted. Since the spacer is stamped from a flat sheet, a structure for holding the lead wires cannot be freely formed as in a die casting method, but formation of the small hole according to the present invention is easy. During manufacturing, after the lead wires and have been inserted through the small hole, if they are processed in the following fabrication step, there is no possibility that force will be applied to the boundary portion between a coil and the lead wire extending from a wire of the coil which would peel a wire of the coil off.
    Type: Grant
    Filed: June 22, 1998
    Date of Patent: March 7, 2000
    Assignee: International Business Machines Corporation
    Inventors: Hitoshi Tsujino, Mutsuro Ohta, David W. Albrecht
  • Patent number: 5896245
    Abstract: In attaching a load beam to a carriage, the swage attachment is used between the carriage and a mountplate, while the load beam is attached to the mountplate by welding and other binding means, to create a structure in which the load beam does not come into direct contact with the swage part, so that a structure is obtained in which the load beam is hardly subject to deformation or other direct influences from the swage operation. In addition, by forming the attaching plate side of the load beam to envelope a carriage, or by extending both sides of the load beam from the central portion in the longitudinal direction toward the carriage, a structure improved in the stability of load beam attachment is obtained.
    Type: Grant
    Filed: July 5, 1996
    Date of Patent: April 20, 1999
    Assignee: International Business Machines Corporation
    Inventors: Akihiko Aoyagi, Hiroyasu Tsuchida, Tatsuo Nakamoto, Hitoshi Tsujino, Shingo Tsuda, Mutsuro Ohta
  • Patent number: 5818657
    Abstract: A method and system for overcoming force which inhibits movement of a data storage device are provided. The invention includes generating momentum in a moveable member and then utilizing the momentum of the moveable member to generate a large impulse force on a stationary body (e.g., the data storage device) to overcome the movement-inhibiting force thereon. This is accomplished by allowing the moveable member to move along a trajectory independently of the stationary body, thereby building momentum in the moveable member. The subsequent impact of the member on the body overcomes the force. The moveable member can then also be used, in one embodiment, to continue driving the body during system operation.
    Type: Grant
    Filed: July 31, 1996
    Date of Patent: October 6, 1998
    Assignee: International Buisness Machines Corporation
    Inventors: Sri Muthuthamby Sri-Jayantha, Vijayeshwar Das Khanna, Suresh Kumar, Mutsuro Ohta, Kohji Serizawa
  • Patent number: 5796555
    Abstract: To attach a suspension assembly to the actuator, the suspension is connected to a mount plate. The inner diameter of the swaging boss in this mount plate differs depending upon if it is on a lower or upper suspension of an actuator arm. After setting only the mount plates with bosses of a larger inner diameter and performing the first swage, the mount plates of the smaller inner diameter are set and a second swage is performed in a different direction. Even when performing this bidirectional swage, a boss caulked with the first swage is subjected to no deformation after a later swage and therefore a stable swage is possible.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: August 18, 1998
    Assignee: International Business Machines Corporation
    Inventors: Akihiko Aoyagi, Mutsuro Ohta, Nobuyuki Hashi, Hitoshi Tsujino
  • Patent number: 5628571
    Abstract: A bearing structure used in a pivot bearing for freely supporting the rotation of a head arm of a hard disk drive (HDD). The bearing structure includes an inner shaft, an outer sleeve, a pair of roller bearings axially spaced and interposed between the inner shaft and the outer sleeve, and a preload spring for exerting a preload on the roller bearings. The roller bearings may be provided with an outer race that is attached to the outer sleeve. Nevertheless, the coefficients of linear expansion of the inner shaft and the outer sleeve are chosen so that they are different in an axial direction. Accordingly, the coefficients of linear expansion of the inner shaft and the outer sleeve are chosen so that the rotation torque derived from the preload becomes higher as the temperature rises and lower as the temperature falls. However, the rotational torque becomes lower as the temperature of a lubricant rises and higher as the lubricant temperature falls.
    Type: Grant
    Filed: September 15, 1995
    Date of Patent: May 13, 1997
    Assignee: International Business Machines Corporation
    Inventors: Mutsuro Ohta, Kohji Takahashi, Shingo Tsuda