Patents by Inventor Jifang Tian

Jifang Tian 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: 11588377
    Abstract: A fan motor suitable for use in an electronic device, such as a consumer electronic device, is disclosed. The fan motor includes a stator and a rotor. In order to minimize a varying torque applied to the rotor, the stator includes modifications. For example, the stator includes stator teeth, each with an arc defined by a radius of curvature that varies. The radius (from a reference point to the arc) can vary in accordance with a sinusoidal curve. Furthermore, the corners of each stator tooth may be rounded. The rounded corners of the stator teeth may include a uniform (or constant, non-varying) radius of curvature. These enhancement are designed to provide a more uniform torque by the stator to the rotor. As a result, the rotation of the rotor is subject to smaller fluctuations, and the fan motor undergoes less vibration and generates less acoustical noise.
    Type: Grant
    Filed: February 14, 2020
    Date of Patent: February 21, 2023
    Assignee: APPLE INC.
    Inventors: Jifang Tian, Cheng Ping Tan, Enoch Mylabathula
  • Publication number: 20210257882
    Abstract: A fan motor suitable for use in an electronic device, such as a consumer electronic device, is disclosed. The fan motor includes a stator and a rotor. In order to minimize a varying torque applied to the rotor, the stator includes modifications. For example, the stator includes stator teeth, each with an arc defined by a radius of curvature that varies. The radius (from a reference point to the arc) can vary in accordance with a sinusoidal curve. Furthermore, the corners of each stator tooth may be rounded. The rounded corners of the stator teeth may include a uniform (or constant, non-varying) radius of curvature. These enhancement are designed to provide a more uniform torque by the stator to the rotor. As a result, the rotation of the rotor is subject to smaller fluctuations, and the fan motor undergoes less vibration and generates less acoustical noise.
    Type: Application
    Filed: February 14, 2020
    Publication date: August 19, 2021
    Inventors: Jifang TIAN, Cheng Ping TAN, Enoch MYLABATHULA
  • Patent number: 9947370
    Abstract: A hard disk drive assembly having a hard disk drive positioned within an external housing. Isolators formed of a resilient material, such as an elastomeric material, are interposed between the hard disk drive and an external housing. The isolators also preferably having a plurality of openings that extend there through that lower the stiffness of the isolators during small deflections such as those caused by vibrations, but large deflections, such as those caused by shocks cause the openings or holes to close there by generating greater stiffness is response to external shocks.
    Type: Grant
    Filed: June 10, 2015
    Date of Patent: April 17, 2018
    Assignee: Western Digital Technologies, Inc.
    Inventors: Cheng Jin, Jifang Tian, Michael J. Herrmann, Zachary P. Hills
  • Patent number: 9401165
    Abstract: A method and system to monitor stability of magnetic head loading and unloading beside media for a data storage system is described. A shock sensor is utilized to detect shock during preloading of a magnetic head beside recording media, during loading of a magnetic head beside recording media, during pre-unloading of a magnetic head from the recording media, and/or during unloading of a magnetic head from the recording media. In an aspect, a desired pitch static attitude (PSA) and roll static attitude (RSA) of a slider is determined. In an aspect, the stability of a magnetic head is assessed and screened while on the fly and during head gimbal assembly (HGA) design and testing to improve overall data storage device reliability.
    Type: Grant
    Filed: June 13, 2014
    Date of Patent: July 26, 2016
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jifang Tian, Alain Chahwan
  • Patent number: 9361947
    Abstract: A hard disk drive assembly having a hard disk drive positioned within an enclosure. A shock support is interposed between the hard disk drive and at least one wall of the enclosure so that external shocks on the enclosure are transmitted through the shock support. The shock support can be either a rigid support made of metal or a resilient support made of elastomeric material.
    Type: Grant
    Filed: June 10, 2015
    Date of Patent: June 7, 2016
    Assignee: Western Digital Technologies, Inc.
    Inventors: Baekho Heo, Cheng Jin, Sara Sahebjam-Atabaki, Jifang Tian, Zachary P. Hills
  • Patent number: 9299384
    Abstract: A disk drive having a hub comprising a top surface and a non-circular protrusion extending upward from the top surface, a disk clamp comprising a wall portion and a non-circular opening formed through the clamp, the opening configured to receive the non-circular protrusion extending upward from the top surface of the hub; and at least one disk supported by the hub, wherein the non-circular protrusion extending upward from the top surface of the hub is inserted into the opening formed in the clamp, and wherein an outer annular portion of the clamp engages the disk to provide clamping force.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: March 29, 2016
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jifang Tian, Jian Yang, Qiang Yang
  • Patent number: 9142225
    Abstract: An apparatus includes: a media; a head over the media; a primary-actuator coupled to the head; and control circuitry, coupled to the primary-actuator and a secondary-actuator, configured to limit a secondary-actuator slew rate.
    Type: Grant
    Filed: June 18, 2014
    Date of Patent: September 22, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Min Chen, Alexander Babinski, Yanan Huang, Young-Hoon Kim, Duc T. Phan, Jifang Tian
  • Patent number: 9116066
    Abstract: A vibration testing apparatus comprises a first mooring bar coupled to the base; a second mooring bar coupled to the base such that the second mooring bar is disposed away from and faces the first mooring bar to define a space between the first and second mooring bars; a first strap comprising a first end secured to the first mooring bar, and a second strap comprising a first end secured to the first mooring bar. A second end of each of the first and second straps may be secured to the second mooring bar such that the first and second straps span the space between the first and second mooring bars and such that a tension on at least one of the first and second strap is controllable.
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: August 25, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jifang Tian, Hongqi Li, William Flynn, Xiaoping Hu, Francisco Obregon
  • Patent number: 9076471
    Abstract: For a disk drive involving a disk; a head; and control circuitry having a servo control system operable to actuate the head, the control circuitry may be configured to determine a magnitude of acceleration readings, the acceleration readings involving at least three degrees of freedom, wherein when a magnitude of the acceleration readings is less than a first threshold, the control circuitry confirms a free fall, wherein when the magnitude is between the first and second threshold, the control circuitry confirms a tilt drop. During the tilt drop and the free fall, the control circuitry is further configured to actuate the head to park and monitor the shock impact.
    Type: Grant
    Filed: September 26, 2013
    Date of Patent: July 7, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Min Chen, Sanghoon Chu, Jifang Tian, Zhongjie Li, Hien T. Chu
  • Patent number: 9036295
    Abstract: A novel information storage device is disclosed and claimed. The information storage device includes a device housing with a generally rectangular bay to accommodate a disk drive. The generally rectangular bay includes a base portion and a plurality of side portions. The information storage device further includes a damping insert sheet disposed between the disk drive and the base portion. The damping insert sheet has a plurality of elastomeric cushions, for example with a cushion thickness in the range 0.5 mm to 10 mm, and a spanning sheet, for example having a sheet thickness in the range 0.02 mm to 0.35 mm. Each of the plurality of elastomeric cushions is attached to the spanning sheet. Each of the plurality of elastomeric cushions contacts and is compressed between the generally rectangular bay and the disk drive.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: May 19, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Shawn E. Casey, Jifang Tian, Tegan Campbell, Hongqi Li, William Flynn
  • Patent number: 8982513
    Abstract: A disk drive head gimbal assembly includes a laminated flexure with a tongue having an actuated portion that rotates about an axis of rotation by expansion of a first adhered piezoelectric element relative to a second adhered piezoelectric element. A non-actuated portion of the tongue adjoins and forms a bridge between two outrigger beams, with a dimple contact location that is in contact with a dimple of the load beam and through which the axis of rotation passes. A read head is adhered, closer to its leading end than to its trailing end, to the actuated portion of the tongue. Each of the first and second piezoelectric elements has an anchored end that is adhered to the bridge, closer to the trailing end of the read head, and an opposing actuated end adhered to the actuated portion of the tongue, closer to the leading end of the read head.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: March 17, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jifang Tian, Jian Yang, Qiang Yang, William S. Wang, Yih-Jen D. Chen
  • Patent number: 8797691
    Abstract: A disk drive head gimbal assembly includes a laminated flexure with a tongue having an actuated portion that rotates about an axis of rotation by expansion of an adhered piezoelectric element. A non-actuated portion of the tongue adjoins and forms a bridge between two outrigger beams, with a dimple contact location that is in contact with a dimple of the load beam and through which the axis of rotation passes. The piezoelectric element has an anchored end that is adhered to the non-actuated portion of the tongue, and an opposing actuated end adhered to the actuated portion. The actuated portion of the tongue includes first and second head mounting plates that are each adhered to the read head. Each of the head mounting plates is connected to the non-actuated portion of the tongue by an elongated compliant member that is oriented radially with respect to the dimple contact location.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: August 5, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jifang Tian, Jian Yang, Qiang Yang, William S. Wang, Yih-Jen D. Chen
  • Patent number: 8705201
    Abstract: A novel information storage device is disclosed and claimed. The information storage device includes a device housing with a generally rectangular bay to accommodate a disk drive. The generally rectangular bay includes a base portion and a plurality of side portions. The information storage device further includes a damping insert sheet disposed between the disk drive and the base portion. The damping insert sheet has a plurality of elastomeric cushions, for example with a cushion thickness in the range 0.5 mm to 10 mm, and a spanning sheet, for example having a sheet thickness in the range 0.02 mm to 0.35 mm. Each of the plurality of elastomeric cushions is attached to the spanning sheet. Each of the plurality of elastomeric cushions contacts and is compressed between the generally rectangular bay and the disk drive.
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: April 22, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Shawn E. Casey, Jifang Tian, Tegan Campbell, Hongqi Li, William Flynn
  • Patent number: 8693139
    Abstract: A disk drive having a hub comprising a top surface and a non-circular protrusion extending upward from the top surface, a disk clamp comprising a wall portion and a non-circular opening formed through the clamp, the opening configured to receive the non-circular protrusion extending upward from the top surface of the hub; and at least one disk supported by the hub, wherein the non-circular protrusion extending upward from the top surface of the hub is inserted into the opening formed in the clamp, and wherein an outer annular portion of the clamp engages the disk to provide clamping force.
    Type: Grant
    Filed: August 2, 2012
    Date of Patent: April 8, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jifang Tian, Jian Yang, Qiang Yang
  • Patent number: 8667667
    Abstract: A disk drive includes a disk drive base comprising a first metal material. The disk drive base may include a first opening and a first attachment feature to which a head actuator assembly pivot may be attached. A motor support may be embedded in the first opening in the disk drive base. The motor support consists of a second metal material having a damping coefficient higher than that of the first metal material. A rotary spindle may be attached to the motor support, and a disk may be attached to the rotary spindle.
    Type: Grant
    Filed: January 13, 2011
    Date of Patent: March 11, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Diep L. Nguyen, Jifang Tian, Hongqi Li
  • Publication number: 20140036392
    Abstract: A disk drive having a hub comprising a top surface and a non-circular protrusion extending upward from the top surface, a disk clamp comprising a wall portion and a non-circular opening formed through the clamp, the opening configured to receive the non-circular protrusion extending upward from the top surface of the hub; and at least one disk supported by the hub, wherein the non-circular protrusion extending upward from the top surface of the hub is inserted into the opening formed in the clamp, and wherein an outer annular portion of the clamp engages the disk to provide clamping force.
    Type: Application
    Filed: August 2, 2012
    Publication date: February 6, 2014
    Applicant: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: JIFANG TIAN, JIAN YANG, QIANG YANG
  • Patent number: 8593764
    Abstract: A disk drive includes a voice coil actuator, and a rotary fine actuator that is attached to the head mounting tongue of the flexure of a suspension assembly. The head is positioned during operation of the disk drive by a novel method. An electrical current is driven through a coil of the voice coil actuator to torque it towards a desired coarse position. First and second voltages are applied across first and second piezoelectric elements attached to the flexure, respectively. The first and second voltages cause longitudinal deformation of the first and second piezoelectric elements, respectively, the longitudinal deformation consisting of expansion relative to a zero-voltage state. The first and second voltages do not switch polarity during normal operation of the first and second piezoelectric elements.
    Type: Grant
    Filed: November 8, 2012
    Date of Patent: November 26, 2013
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jifang Tian, Qiang Yang, Jian Yang
  • Publication number: 20130155545
    Abstract: A novel information storage device is disclosed and claimed. The information storage device includes a device housing with a generally rectangular bay to accommodate a disk drive. The generally rectangular bay includes a base portion and a plurality of side portions. The information storage device further includes a damping insert sheet disposed between the disk drive and the base portion. The damping insert sheet has a plurality of elastomeric cushions, for example with a cushion thickness in the range 0.5 mm to 10 mm, and a spanning sheet, for example having a sheet thickness in the range 0.02 mm to 0.35 mm. Each of the plurality of elastomeric cushions is attached to the spanning sheet. Each of the plurality of elastomeric cushions contacts and is compressed between the generally rectangular bay and the disk drive.
    Type: Application
    Filed: December 20, 2011
    Publication date: June 20, 2013
    Applicant: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Shawn E. Casey, Jifang Tian, Tegan Campbell, Hongqi LI, William Flynn
  • Patent number: 8446694
    Abstract: A head gimbal assembly (HGA) for a disk drive includes a mounting plate configured to be attachable to an actuator arm, a load beam extending from the mounting plate, a laminated flexure, first and second piezoelectric elements, and a read head. The laminated flexure includes a fixed portion that is attached to the load beam, and a head mounting tongue that is connected to the fixed portion by first and second compliant members. The read head is bonded to the head mounting tongue. The laminated flexure also includes first and second piezoelectric element receiving windows, each adjacent a respective one of the first and second compliant members. The first and second piezoelectric elements are each disposed within a respective one of the first and second piezoelectric element receiving windows.
    Type: Grant
    Filed: September 25, 2012
    Date of Patent: May 21, 2013
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jifang Tian, Jian Yang, Qiang Yang
  • Patent number: 8411389
    Abstract: Described herein is a disk drive with a fluid bearing having a sleeve defining a bore that extends through a portion of the sleeve along an axis defined by the bore. The sleeve can have a first contact surface that extends in a direction transverse to the axis. A spindle is rotationally received within the bore, and the spindle and the sleeve permit relative rotational movement when the spindle is positioned within the bore. The spindle has a stopper with a second contact surface that extends in a direction transverse to the axis when the spindle is positioned within the bore. A portion of at least one of the first and second contact surfaces includes a softer material than that of the spindle and the bearing sleeve, and the first and second contact surfaces are configured to engage each other upon relative axial movement between the spindle and the sleeve.
    Type: Grant
    Filed: June 29, 2010
    Date of Patent: April 2, 2013
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jifang Tian, Jian Yang