Patents by Inventor Khosrow Mohajerani

Khosrow Mohajerani 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: 7369368
    Abstract: A head stack assembly for a disk drive includes an actuator body. The actuator body includes a pair of sides, a bore defining a longitudinal axis, a first slot extending between the pair of sides, a second slot extending along a direction perpendicular to the longitudinal axis, the second slot extending from the first slot to the bore. The head stack assembly further includes a coil portion cantilevered from the actuator body in one direction and an actuator arm cantilevered from the actuator body in a direction opposite from the coil portion.
    Type: Grant
    Filed: October 15, 2004
    Date of Patent: May 6, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventor: Khosrow Mohajerani
  • Patent number: 6678121
    Abstract: An actuator arm for a disc drive data storage device has an upper outer surface in a first plane, a lower outer surface in a second plane substantially parallel to the first plane, a peripheral outer surface substantially perpendicular to the first and second planes, and a voice coil embedded within the outer surfaces of the actuator arm. The actuator arm is used in a disc drive containing one or more data storage discs and preferably has a pre-amplifier embedded within the outer surfaces of the actuator arm as well as conductors preferably between the read/write head and the pre-amplifier within the outer surfaces of the actuator arm.
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: January 13, 2004
    Assignee: Seagate Technology LLC
    Inventors: Ernest Paul Lee, Alexander Wei Chang, Khosrow Mohajerani, Michael Henry Lennard
  • Patent number: 6381101
    Abstract: An apparatus and method for minimizing the risk of damage to a disc surface caused by contact between a disc and a slider in a head disc assembly of a disc drive. The apparatus includes a flexure and slider which are biased away from the disc when the disc is stationary and one or more aerodynamic airfoils attached to the flexure. The airfoils are attached to the flexure and extend from the flexure at an angle relative to the disc so as to interact with an air flow caused when the disc spins to force the flexure and the attached slider to move toward the disc during operation of the disc drive.
    Type: Grant
    Filed: December 30, 1999
    Date of Patent: April 30, 2002
    Assignee: Seagate Technology LLC
    Inventors: Khosrow Mohajerani, Wallis Allen Dague
  • Patent number: 6362933
    Abstract: A system for loading a transducing head (22) to a flying elevation proximate a rotating surface of a disc (16) is disclosed. The system includes a piezoelectric device (40) that is selectively expanded and contracted to control a height of the head (22) on a flexure spring (14) from the surface of the disc (16). The system preferably includes control circuitry (50) for generating electrical control signals to manage the expansion and contraction of the piezoelectric device (40) according to operating characteristics of the disc (16).
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: March 26, 2002
    Assignee: Seagate Technology LLC
    Inventors: Joseph M. Sampietro, Khosrow Mohajerani, Anoush M. Fard, Richard G. Krum, Jeffrey G. Barina, Muhammad A. Hawwa
  • Publication number: 20020021532
    Abstract: An actuator arm for a disc drive data storage device has an upper outer surface in a first plane, a lower outer surface in a second plane substantially parallel to the first plane, a peripheral outer surface substantially perpendicular to the first and second planes, and a voice coil embedded within the outer surfaces of the actuator arm. The actuator arm is used in a disc drive containing one or more data storage discs and preferably has a pre-amplifier embedded within the outer surfaces of the actuator arm as well as conductors preferably between the read/write head and the pre-amplifier within the outer surfaces of the actuator arm.
    Type: Application
    Filed: June 28, 2001
    Publication date: February 21, 2002
    Inventors: Ernest Paul Lee, Alexander Wei Chang, Khosrow Mohajerani, Michael Henry Lennard
  • Patent number: 6298545
    Abstract: A system for positioning a transducing head in a disc drive device over a selected track of a rotatable disc includes an actuator arm which is rotatable about an axis, a head suspension mechanism connected to the actuator arm, and a slider carrying a transducing head and supported by the head suspension mechanism. A low resolution motor moves the actuator arm about the axis to effect coarse movement of the head between tracks of the disc. A piezoelectric element is embedded in the actuator arm to distort the arm to effect fine positioning of the head. Control circuitry distributes electrical signals to the low resolution motor and the piezoelectric element to selectively control movement thereof. The piezoelectric element is embedded in the actuator arm by removing a predetermined amount of material from the actuator arm and bonding the piezoelectric element in the resulting space in the actuator arm.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: October 9, 2001
    Assignee: Seagate Technology LLC
    Inventors: Khosrow Mohajerani, Joseph M. Sampietro, Anoush M. Fard, Jeffrey G. Barina, Muhammad A. Hawwa, LeRoy A. Volz, Tien Q. Le, Daniel R. Vigil
  • Patent number: 6255750
    Abstract: An apparatus and method for reducing the effects of disc flutter or noise in a disc drive incorporates damping material or rings that are clamped or sandwiched against mounted information storage disc at a distance from a hub portion of a spindle assembly. The damping rings are positioned between a disc clamp and a bottom annular flange of the hub portion so as to engage and reduce vibrations in the mounted information storage disc or discs. The damping rings can be retained in grooves defined in the disc clamp, bottom annular flange and top and bottom surfaces of an annular disc spacer. Alternatively, the damping rings can be reatined on tubular sidewalls defined on the disc clamp, bottom annular flange of the hub portion and annular disc spacer. The arrangement of damping rings absorbs energy transmitted by vibrations in information storage disc and thus minimizes the effects of disc flutter in a disc drive.
    Type: Grant
    Filed: December 30, 1999
    Date of Patent: July 3, 2001
    Assignee: Seagate Technology LLC
    Inventors: Khosrow Mohajerani, Wallis A. Dague
  • Patent number: 6157116
    Abstract: Noise effects in a disc drive having a disc on a rotating spindle in a housing are reduced by inducing vibrations in the housing of the disc drive that at least partially cancel a characteristic acoustic noise signal of the drive.
    Type: Grant
    Filed: January 28, 1998
    Date of Patent: December 5, 2000
    Assignee: Seagate Technology LLC
    Inventors: Joseph M. Sampietro, Muhammad A. Hawwa, Khosrow Mohajerani, Anoush M. Fard, Jeffrey G. Barina
  • Patent number: 6108175
    Abstract: A head flexure assembly for positioning a transducing head over a selected track of a rotatable disc in a disc drive system having an actulator arm and head suspension includes a bimorph piezoelectric microactuator having first and second ends. The first end of the microactuator is attached to the actuator arm, and a flexure is attached to the second end of the microactuator. A slider carrying the transducing head is attached to the flexure.
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: August 22, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Muhammad A. Hawwa, Joseph M. Sampietro, Anoush M. Fard, Jeffrey G. Barina, Khosrow Mohajerani
  • Patent number: 6052251
    Abstract: A system for positioning a transducing head in a disc drive device over a selected track of a rotatable disc includes an actuator arm which is rotatable about an axis, a head suspension mechanism connected to the actuator arm, and a slider carrying a transducing head and supported by the head suspension mechanism. A low resolution motor moves the actuator arm about the axis to effect coarse movement of the head between tracks of the disc. A piezoelectric element is embedded in the actuator arm to distort the arm to effect fine positioning of the head. Control circuitry distributes electrical signals to the low resolution motor and the piezoelectric element to selectively control movement thereof. The piezoelectric element is embedded in the actuator arm by removing a predetermined amount of material from the actuator arm and bonding the piezoelectric element in the resulting space it the actuator arm.
    Type: Grant
    Filed: May 12, 1997
    Date of Patent: April 18, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Khosrow Mohajerani, Joseph M. Sampietro, Anoush M. Fard, Jeffrey G. Barina, Muhammad A. Hawwa, LeRoy A. Volz, Tien Q. Le, Daniel R. Vigil
  • Patent number: 6025975
    Abstract: A system for positioning a transducing head of a disc drive over a selected track (42) of a rotatable disc (40) includes an actuator assembly (20,50) having an E-block body (25) including a cavity (37), at least one actuator arm (30) extending from the E-block body (25), a head suspension mechanism (34,36,38) including the transducing head connected to an end of the actuator arm (30), and a pivot cartridge (26) in the cavity (37) in the E-block body (25). The E-block body (25) is attached to the pivot cartridge (26) and forms a hinge point (39) between the E-block body (25) and the pivot cartridge (26). A low resolution motor (22) rotates the actuator assembly (20,50) about an axis (24) to effect coarse positioning of the head with respect to the selected track (42) of the rotatable disc (40).
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: February 15, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Anoush M. Fard, Khosrow Mohajerani, Joseph M. Sampietro, Jeffrey G. Barina, Muhammad A. Hawwa
  • Patent number: 6002549
    Abstract: A disc drive has rotatable recording disc and a transducing head on a slider arranged to fly over a surface of the disc when the disc is rotated. The slider is supported by an actuator arm operatively coupled to an actuator motor to position the transducing head over a selected track of the disc. The slider is arranged to land on the disc surface when the disc is not rotated. Dithering means vibrates the slider when the slider is on the disc surface to reduce stiction between the slider and the disc surface thereby reducing the torque required to commence flying of the slider.
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: December 14, 1999
    Assignee: Seagate Technology, Inc.
    Inventors: Alan David Berman, Khosrow Mohajerani, Anoush Mahabadi Fard, Joseph Michael Sampietro, Zine-Eddine Boutaghou
  • Patent number: 5732458
    Abstract: A clamp ring for a disk stack assembly of a computer disk drive unit includes a lower surface which includes an arcuate rolling contact surface that uniformly distributes a load applied to the clamp ring to components of the disk stack assembly underlying the clamp ring without damaging such disk stack components on load-induced flexion of the clamp ring. A cantilevered section of the clamp ring is disposed radially inwardly of the arcuate rolling contact surface, and is defined by a portion of the lower surface which is raised relative to an adjacent portion of the arcuate rolling contact surface so as to not contact the underlying disk stack components on load-induced flexion of the clamp ring. In use, the clamp ring is heated and then placed over the disk stack components to be clamped together.
    Type: Grant
    Filed: April 29, 1996
    Date of Patent: March 31, 1998
    Assignee: Seagate Technology, Inc.
    Inventors: Michael B. Moir, Khosrow Mohajerani
  • Patent number: 5724718
    Abstract: A process for assembling a clamp ring to a disk stack assembly of a computer disk drive unit. The clamp ring includes a lower surface which includes an arcuate rolling contact surface that uniformly distributes a load applied to the clamp ring to components of the disk stack assembly underlying the clamp ring without damaging such disk stack components on load-induced flexion of the clamp ring. A cantilevered section of the clamp ring is disposed radially inwardly of the arcuate rolling contact surface, and is defined by a portion of the lower surface which is raised relative to an adjacent portion of the arcuate rolling contact surface so as to not contact the underlying disk stack components on load-induced flexion of the clamp ring. In use, the clamp ring is heated and then placed over the disk stack components to be clamped together.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: March 10, 1998
    Assignee: Seagate Technology, Inc.
    Inventors: Michael B. Moir, Khosrow Mohajerani
  • Patent number: 5712746
    Abstract: A clamp ring for a disk stack assembly of a computer disk drive unit includes a lower surface which includes an arcuate rolling contact surface that uniformly distributes a load applied to the clamp ring to components of the disk stack assembly underlying the clamp ring without damaging such disk stack components on load-induced flexion of the clamp ring. A cantilevered section of the clamp ring is disposed radially inwardly of the arcuate rolling contact surface, and is defined by a portion of the lower surface which is raised relative to an adjacent portion of the arcuate rolling contact surface so as to not contact the underlying disk stack components on load-induced flexion of the clamp ring. In use, the clamp ring is heated and then placed over the disk stack components to be clamped together.
    Type: Grant
    Filed: March 4, 1997
    Date of Patent: January 27, 1998
    Assignee: Seagate Technology, Inc.
    Inventors: Michael B. Moir, Khosrow Mohajerani
  • Patent number: 5526203
    Abstract: A data storage device includes a memory storage disc, a spindle motor, a read head for sensing data stored on the disc, an actuator for supporting the read head with respect to the disc, and an air baffle between the actuator and the disc. The spindle motor rotates the memory storage disc causing air flow adjacent a surface of the disc. The air baffle is positioned between the disc and the actuator to isolate the actuator from the air flow adjacent the surface of the disc.
    Type: Grant
    Filed: December 7, 1994
    Date of Patent: June 11, 1996
    Assignee: Seagate Technology, Inc.
    Inventors: Khosrow Mohajerani, Eldon L. Nelson
  • Patent number: 5482381
    Abstract: An actuator assembly for a computer disk drive includes a pivot shaft which defines a pivot axis for the actuator assembly, a pivotable actuator which encircles the pivot shaft, a bearing assembly disposed between the pivot shaft and the actuator, and a labyrinth seal adjacent to a lower edge of the bearing assembly. The labyrinth seal is incorporated into the pivot shaft and includes an axially extending ridge which is disposed in facing relation to a lower edge of the bearing assembly. The labyrinth seal also includes a reservoir disposed radially inwardly of the axially extending ridge, and a flange which extends radially outwardly of the axially extending ridge. The flange includes both axially and radially-facing surfaces which are disposed in facing relation to oppositely facing surfaces of the actuator. Very small air gaps are maintained between the labyrinth seal and the actuator assembly, on the order of 0.003 to 0.
    Type: Grant
    Filed: June 16, 1994
    Date of Patent: January 9, 1996
    Assignee: Seagate Technology, Inc.
    Inventors: Richard G. Krum, Eldon L. Nelson, Khosrow Mohajerani, Michael B. Moir
  • Patent number: 5430589
    Abstract: A computer disk drive unit includes a housing having a lower base and an upper removable cover which define a disk storage compartment therebetween. A shaft fixed to the lower base supports a plurality of memory storage disks for rotation within the disk storage compartment. An elastomeric snubber extends between an upper end of the shaft and the upper housing cover, for preventing direct contact and absorbing vibration between the shaft and the upper housing cover. The snubber is a cylindrical member having a lower solid section disposed within a recess in the upper end of the shaft, and an upper tubular section which is compressed as the upper housing cover is secured to the lower base. The upper housing cover includes a thickened portion whereat the upper tubular section of the snubber contacts the cover.
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: July 4, 1995
    Assignee: Seagate Technology, Inc.
    Inventors: Michael B. Moir, Khosrow Mohajerani, Richard G. Krum
  • Patent number: 4879617
    Abstract: An actuator assembly for a disk drive system includes an actuator pivotally mounted to a shaft, and a coil assembly. A counterbalance portion of the actuator provides a recess wherein a portion of the coil assembly is slidably inserted. The coil assembly includes a bobbin which has a dovetail portion having at least two precision positioning surfaces which, when placed within the counterbalance recess, interact with corresponding precision positioning surfaces provided within the counterbalance recess. In order to accurately position the coil assembly with respect to the actuator, an outward force is applied to the coil assembly perpendicular to the pivot axis to cause facing pairs of the precision positioning surfaces of the coil assembly and the counterbalance recess to bear against one another, and align a dowel/pin alignment passageway extending through the counterbalance with a dowel/pin recess provided in the bobbin.
    Type: Grant
    Filed: March 25, 1988
    Date of Patent: November 7, 1989
    Assignee: Rigidyne Corporation
    Inventors: Joseph M. Sampietro, Khosrow Mohajerani