Patents by Inventor M Rifat Ullah

M Rifat Ullah 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).

  • Publication number: 20100244385
    Abstract: According to the present invention, an annular face seal arrangement for a gas turbine engine is provided that includes a mounting ring, a mounting member, a rotor, and a stator. The mounting ring has a width extending between a first axial end and a second axial end. The mounting member has a clamp portion and a biasing portion. The clamp portion extends axially between a first clamping surface and a second clamping surface. The biasing portion includes a first segment and a second segment. The second segment has a width and a rotor contact surface. The rotor has a rotor seal surface and a clamp portion having a width. The stator has a stator seal surface that is aligned with the rotor seal surface. The mounting ring is disposed radially inside of the rotor and radially inside of at least part of the biasing portion, and is disposed in contact with the second clamping surface of the clamp portion. The rotor contact surface of the biasing portion is disposed in contact with the rotor.
    Type: Application
    Filed: March 31, 2009
    Publication date: September 30, 2010
    Applicant: United Technologies Corporation
    Inventor: M. Rifat Ullah
  • Patent number: 6655695
    Abstract: A composite face seal having an annular seal rotor with a metal base portion and a radially extending flange. The flange having first and second axially facing surfaces. A first ceramic ring is mounted to the first surface of the flange by a first braze joint and a second ceramic ring is mounted to the second surface of the flange by a second braze joint. The composite face seal assembly further includes an annular stator having an axially facing surface that sealingly engages an axially facing surface of one of the ceramic rings. Each of the braze joints may comprise a molybdenum ring disposed between two braze rings or, for thicker seal assemblies, molybdenum and nickel rings disposed between braze rings.
    Type: Grant
    Filed: February 13, 2001
    Date of Patent: December 2, 2003
    Assignee: Honeywell International Inc.
    Inventors: Steven E. Sund, Charles J. Gasdaska, James V. Guiheen, Lennox Bruce, M. Rifat Ullah, William L. Giesler
  • Patent number: 6322081
    Abstract: A circumferential seal for sealing between a rotating shaft and a stationary housing circumscribing the shaft. The seal comprises a stator mounted to said housing and having a radially inward facing carbon portion and a rotor with a ceramic sealing member having a radially outward facing surface in rubbing contact with said carbon portion. The rotor also includes a metal clamping means for mounting the ceramic sealing member to the shaft. The clamping means includes an axial flexible clamping member, and a radial flexible clamping member that together clamp onto a mounting flange of the ceramic sealing member when exposed to the compressive force of a lockup assembly.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: November 27, 2001
    Assignee: Ceramic Engineering Consulting, Inc.
    Inventors: M Rifat Ullah, Michael F. O'Brien, Fred Fuller, Gary Boyd
  • Patent number: 5639096
    Abstract: Disclosed is an oil film cooled face seal that is comprised of an annular stator having a flat surface in rubbing contact with the flat sealing surface of a rotor. The rotor has a flange portion extending radially from a base portion. The base portion has a plurality of holes extending radially therethrough in fluid communication with a source of cooling oil. One side of the flange portion comprises the flat sealing surface. The opposite side, or backface, has a plurality of external radially spaced apart annular grooves criss-crossing a plurality of external circumferentially spaced apart substantially radial grooves. Each of the radial grooves is aligned with and in fluid communication with a corresponding hole in the base portion, and extends fully across the backface.
    Type: Grant
    Filed: July 11, 1996
    Date of Patent: June 17, 1997
    Assignee: AlliedSignal Inc.
    Inventor: M. Rifat Ullah
  • Patent number: 5626347
    Abstract: A face seal comprising an annular carbon stator having a flat sealing surface in rubbing contact with a flat sealing surface of an annular metallic rotor. The rotor has a head portion connected to a base portion by a neck portion, that is disposed on the same side of the rotor as the rotor's flat sealing surface. The neck portion has two straight radial surfaces, and is disposed on the same side of the rotor as the rotor's flat sealing surface. The formation of adverse thermal gradients within the rotor can be avoided by adjusting the axial thickness of the neck portion, thereby preventing coning of the rotor.
    Type: Grant
    Filed: February 2, 1996
    Date of Patent: May 6, 1997
    Assignee: AlliedSignal Inc.
    Inventor: M. Rifat Ullah
  • Patent number: 5544896
    Abstract: A face seal includes an annular carbon stator having a flat surface in rubbing contact with the flat surface of a composite annular rotor. The annular rotor has a head portion and a base portion. Embedded in the head portion are high thermal conductivity graphite fibers that are oriented to maximize heat dissipation. Incorporation of graphite fibers makes the rotor resistant to time-dependent creep deformation, thus preserving sealing integrity.
    Type: Grant
    Filed: February 6, 1995
    Date of Patent: August 13, 1996
    Assignee: AlliedSignal Inc.
    Inventors: Barry S. Draskovich, M. Rifat Ullah