Patents by Inventor Raquib Uddin Khan

Raquib Uddin Khan 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: 6678115
    Abstract: A disc drive storage system includes a housing having a central axis, a stationary member that is fixed with respect to the housing and coaxial with the central axis, and a rotatable member that is rotatable about the central axis with respect to the stationary member. A hydro bearing interconnects the stationary member and the rotatable member and includes a lubricating fluid having a base fluid and an additive for reducing the tendency of bubble formation in the lubricating fluid.
    Type: Grant
    Filed: March 13, 2002
    Date of Patent: January 13, 2004
    Assignee: Seagate Technology LLC
    Inventor: Raquib Uddin Khan
  • Publication number: 20030235006
    Abstract: A disc drive storage system including a housing having a central axis, a stationary member that is fixed with respect to the housing and coaxial with the central axis, and a rotatable member that is rotatable about the central axis with respect to the stationary member is described. A hydrodynamic bearing interconnects the stationary member and the rotatable member and includes at least one working surface comprising a low-friction wear resistant coating.
    Type: Application
    Filed: September 27, 2002
    Publication date: December 25, 2003
    Inventors: Mohammad Mahbubul Ameen, Raquib Uddin Khan
  • Publication number: 20030147569
    Abstract: A very thin lubricating coating on one or both of the facing surfaces defining the gap of the hydrodynamic bearing. The lubricant film would need to be very thin, in the range of about 10 Å to 1000 Å, so that the film is thin enough that it does not materially affect the performance of the hydrodynamic bearing gap which is about typically 1-10 &mgr;m. The thin film could be a perfluoropolyether (PFPE) or a mixture of PFPE or a phosphazine derivative. To improve the adhesion and lubricating performance, functional PFPE can be used. For pure metallic surface like steel, phosphate esters can also be used because of its affinity with the metallic surface, e.g., ferrous. For example, the film could be PFPE, or a mixture of PFPE and a phosphazine derivative. The lubricant should be chosen to be thermally stable, and non-reactive with the typical ambient environment.
    Type: Application
    Filed: February 5, 2002
    Publication date: August 7, 2003
    Applicant: SEAGATE TECHNOLOGY LLC.
    Inventors: Raquib Uddin Khan, Gregory Ian Rudd
  • Publication number: 20030086203
    Abstract: A disc drive storage system includes a housing having a central axis, a stationary member that is fixed with respect to the housing and coaxial with the central axis, and a rotatable member that is rotatable about the central axis with respect to the stationary member. A hydro bearing interconnects the stationary member and the rotatable member and includes a lubricating fluid having a base fluid and an additive for reducing the tendency of bubble formation in the lubricating fluid.
    Type: Application
    Filed: March 13, 2002
    Publication date: May 8, 2003
    Inventor: Raquib Uddin Khan
  • Patent number: 6421201
    Abstract: A disc drive spindle motor includes a fixed member coupled to the chassis, and a rotor rotatable about the fixed member for rotating a magnetic storage disc in the contaminant free cavity. A bearing, which may be a hydrodynamic bearing, ball bearing or other bearing type, interconnects the fixed member and the rotor, and supports the rotor for rotation relative to the fixed member. A simple condensation seal is supported from either the fixed member or the rotor, adjacent the bearing opening where outgassing may occur. The seal incorporates a cooling surface which is supported from either the hub/rotor or the fixed member adjacent the region where outgassing occurs; the surface preferably should be wavy, or fin shaped to provide a maximum surface area for better heat transfer and better cooling effect, so that the surface is relatively cooler than the surrounding operating environment. The surface is shaped and made of a material, e.g.
    Type: Grant
    Filed: November 2, 2000
    Date of Patent: July 16, 2002
    Inventors: Raquib Uddin Khan, Matt Loren Shumway, Susan Feng Fan
  • Patent number: 6394654
    Abstract: A very thin lubricating coating on one or both of the facing surfaces defining the gap of the hydrodynamic bearing. The lubricant film would need to be very thin, in the range of about 10 Å to 1000 Å, so that the film is thin enough that it does not materially affect the performance of the hydrodynamic bearing gap which is about typically 1-10 &mgr;m. The thin film could be a perfluoropolyether (PFPE) or a mixture of PFPE or a phosphazine derivative. To improve the adhesion and lubricating performance, functional PFPE can be used. For pure metallic surface like steel, phosphate esters can also be used because of its affinity with the metallic surface, e.g., ferrous. For example, the film could be PFPE, or a mixture of PFPE and a phosphazine derivative. The lubricant should be chosen to be thermally stable, and non-reactive with the typical ambient environment.
    Type: Grant
    Filed: April 28, 1998
    Date of Patent: May 28, 2002
    Assignee: Seagate Technology LLC
    Inventors: Raquib Uddin Khan, Gregory Ian Rudd
  • Patent number: 6292328
    Abstract: A method of creating an improved hydrodynamic fluid bearing is provided which is relatively insensitive to shock vibration changes in load and rotational speed. The hydrodynamic bearing motor in which the bearing is open at both the upper and lower ends, and in which the balance of fluid flow within the bearings is maintained. The assembly of the hydrodynamic bearing is more easily assembled, and the gaps are easily adjusted. In the design of the hydrodynamic bearing, the tolerances for assembly of the various components is minimized; that is, the critical nature of many of the gaps is diminished.
    Type: Grant
    Filed: March 27, 2000
    Date of Patent: September 18, 2001
    Assignee: Seagate Technology LLC
    Inventors: Mohamed Mizanur Rahman, Gunter Karl Heine, Hans Leuthold, Raquib Uddin Khan
  • Patent number: 6137650
    Abstract: A hydrodynamic fluid bearing useful in a bearing cartridge which cartridge may be incorporated into a spindle motor or the like, where the bearing includes a shaft, a conical bearing supported on the shaft, and journal bearings located at least on one side and typically both above and below the conical bearing. A sleeve is mounted for rotation relative to the shaft and defines, in cooperation with the shaft, the gaps necessary for both the conical hydrodynamic bearing and the axial, journal bearings. At an end of the shaft, capillary seals are defined between the sleeve and the shaft so that fluid does not escape from the hydrodynamic bearing. The shaft itself includes a central hole, with bores communicating with both the conical bearing and the journal bearings to maintain appropriate pressure balances.In a further desirable feature, in some embodiments the diameter of one end of the shaft can be made greater than the diameter of the other end of the shaft.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: October 24, 2000
    Assignee: Seagate Technology L.L.C.
    Inventors: Gunter Karl Heine, Mohamed Mizanur Rahman, Raquib Uddin Khan, Hans Leuthold
  • Patent number: 6130802
    Abstract: A method of creating an improved hydrodynamic fluid bearing is provided which is relatively insensitive to shock vibration changes in load and rotational speed. The hydrodynamic bearing motor in which the bearing is open at both the upper and lower ends, and in which the balance of fluid flow within the bearings is maintained. The assembly of the hydrodynamic bearing is more easily assembled, and the gaps are easily adjusted. In the design of the hydrodynamic bearing, the tolerances for assembly of the various components is minimized that is, the critical nature of many of the gaps is diminished.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: October 10, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Mohamed Mizanur Rahman, Gunter Karl Heine, Hans Leuthold, Raquib Uddin Khan
  • Patent number: 6069767
    Abstract: The third dynamic bearing includes a fixed shaft and a sleeve rotating around and surrounding the shaft, and at least first and second thrust plates separated by a portion of the shaft. The shaft includes an axial hole to vent appropriate positions inside the bearing. The axial hole extends from one end of the shaft past at least one of the thrust plates. The axial hole is connected by a radial bore to the bearing gap at a location between the thrust plate closest to that one end of the shaft and the facing counterplate.Alternatively, the axial hole can extend beyond the farthest thrust plate from the one end of the shaft, and can be connected to the bearing gap by a second radial cross-bore. A meniscus forms in the bearing gap on either side of each vent opening, decoupling adjacent bearing sections of the hydrodynamic bearing.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: May 30, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Raquib Uddin Khan, Gunter Karl Heine, Hans Leuthold, Mohamed Mizanur Rahman
  • Patent number: 6069768
    Abstract: A method to create an improved hydrodynamic bearing which is relatively insensitive to changes in load and rotational speed is provided, wherein the hydrodynamic bearing is useful in a spindle motor for a disc drive or the like which is stiffer than known standard spindle motors so that the stability of the system and specifically of the actuator arm and transducer relative to the rotating disc is optimized. The hydrodynamic bearing can also be used as a bearing cartridge or as the cartridge that may be incorporated into a spindle motor or the like, where the bearing includes a shaft and at least two independent bearings each comprising a thrust plate supported on the shaft and a counter plate incorporated in a sleeve which is capable of relative rotation around the shaft.
    Type: Grant
    Filed: April 26, 1999
    Date of Patent: May 30, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Gunter Karl Heine, Raquib Uddin Khan, Mohamed Mizanur Rahman, Hans Leuthold
  • Patent number: 6005748
    Abstract: A method to create an improved hydrodynamic bearing which is relatively insensitive to changes in load and rotational speed is provided, wherein the hydrodynamic bearing is useful in a spindle motor for a disc drive or the like which is stiffer than known standard spindle motors so that the stability of the system and specifically of the actuator arm and transducer relative to the rotating disc is optimized. The hydrodynamic bearing can also be used as a bearing cartridge or as the cartridge that may be incorporated into a spindle motor or the like, where the bearing includes a shaft and at least two independent bearings each comprising a thrust plate supported on the shaft and a counter plate incorporated in a sleeve which is capable of relative rotation around the shaft.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: December 21, 1999
    Assignee: Seagate Technology, Inc.
    Inventors: Gunter Karl Heine, Raquib Uddin Khan, Mohamed Mizanur Rahman, Hans Leuthold
  • Patent number: 5997179
    Abstract: The hydrodynamic bearing gap from one end to the other of the shaft and sleeve combination is effectively separated into sections, with the fluid in each bearing section being contained within that section. The viscosity of the fluid in each bearing section can then be selected to optimize the characteristics of the entire hydrodynamic bearing. Typically, the sections of the bearing adjacent each open end of the bearing would be filled with a fluid with relatively high viscosity. The remaining sections, toward the center of bearing, would typically be filled with a lower viscosity fluid, liquid or gas so that the power consumption within the motor itself would be minimized.
    Type: Grant
    Filed: April 22, 1998
    Date of Patent: December 7, 1999
    Assignee: Seagate Technology, Inc.
    Inventors: Raquib Uddin Khan, Gunter Karl Heine, Mohamed Mizanur Rahman
  • Patent number: 5678929
    Abstract: The hydrodynamic bearing arrangement comprises a journal sleeve defining a journal bore and a journal thrust surface. A shaft is mounted in the journal bore by means of a hydrodynamic journal bearing which permits rotation of the shaft and the journal sleeve relative to one another. A thrust plate extends transversely from the shaft and defines two hydrodynamic thrust bearings in combination with the journal thrust surface and a counterplate which is mounted adjacent to the thrust plate. A porous lubricant reservoir is mounted adjacent to the thrust plate. The porous lubricant reservoir serves to remove wear particles from the lubricant in the bearing arrangement, and provides a supply of lubricant to the hydrodynamic journal and thrust bearings should they become depleted of lubricant.
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: October 21, 1997
    Assignee: Seagate Technology, Inc.
    Inventors: Norbert Steven Parsoneault, Gregory Ian Rudd, Raquib Uddin Khan, Michael David Kennedy