Patents by Inventor Douglas Carl Hofer

Douglas Carl Hofer 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: 20040223844
    Abstract: A method to facilitate sealing between a rotary component and a stationary component is provided. The rotary component includes at least one bucket secured thereon, the bucket having a flow admission side and a flow exit side. The method includes coupling a spill strip in a gap defined between the rotary and stationary component, wherein the spill strip has a substantially flat contact surface, and coupling a cover to a radially outer tip of the bucket, wherein a protrusion extends from the bucket cover to contact the substantially flat contact surface of the spill strip.
    Type: Application
    Filed: May 7, 2003
    Publication date: November 11, 2004
    Inventors: Alison Carol Farrell, Douglas Carl Hofer, Norman Douglas Lathrop, Raymond Kenneth Overbaugh, Kenneth James Robertson, Michael Joseph Boss
  • Patent number: 6814543
    Abstract: A method of modifying a rotor blade, and a rotor blade are provided. The rotor blade is for a steam turbine and it is modified to facilitate altering a natural vibratory frequency of the rotor blade, the rotor blade includes a leading edge, a trailing edge, a first sidewall, and a second sidewall, wherein the first and second sidewalls are connected axially at the leading and trailing edges, and the sidewalls extending radially between a rotor blade root to a rotor blade tip. The method includes determining a vibratory resonance condition of the rotor blade and forming a blade extension between the rotor blade root and the rotor blade tip that alters the determined resonance condition.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: November 9, 2004
    Assignee: General Electric Company
    Inventors: Kevin Joseph Barb, Amir Mujezinovic, Nicholas Francis Martin, Douglas Carl Hofer
  • Publication number: 20040175267
    Abstract: A method for assembling a power system is provided. The method includes coupling a first turbine and second turbine together with a coupling that extends between a first rotor of a first turbine and a second rotor of the second turbine, and such that the first turbine has fluid flow along a first flow path, and the second turbine has fluid flow along a second flow path. The method further includes fixedly coupling an outer wall to the first turbine that directs fluid flow from the first flow path towards the second flow path.
    Type: Application
    Filed: March 3, 2003
    Publication date: September 9, 2004
    Inventors: Douglas Carl Hofer, Daniel Mark Brown, Scott William Blackwell, Norman Douglas Lathrop, Edward John Sharrow
  • Patent number: 6783321
    Abstract: The shafts of upstream and downstream turbines are interconnected by a coupling. A diffuser is provided in an intermediate cavity between the upstream and downstream turbines to recover kinetic energy, as well as minimize or eliminate windage and spinning losses resultant from exposure of the coupling to the flowpath along the turbines. A radial entry inlet provides a supplemental fluid admission into the intermediate cavity, the admission being turned axially and circumferentially for joining with the flow exiting the upstream turbine for combined flow to the downstream turbine.
    Type: Grant
    Filed: November 6, 2002
    Date of Patent: August 31, 2004
    Assignee: General Electric Company
    Inventors: Norman Douglas Lathrop, Daniel Mark Brown, Edward John Sharrow, Kristin Segreto, Douglas Carl Hofer
  • Patent number: 6779972
    Abstract: The root region of a flowpath through a turbine includes a sealing configuration for minimizing leakage flow and secondary aerodynamic losses. Entrance and exit root radial seals are provided between upstream and downstream nozzles at locations radially inwardly of the root region of the flowpath to minimize radial leakage flow. To minimize intrusion flow into the flowpath from rotor pumping action and consequent aerodynamic losses, an exit flow guide on each bucket turns the exiting radial flow in a predominantly axial direction. Additionally, the upstream bucket root radius and nozzle root radius are faired or tapered to minimize the possibility of a protuberance projecting into the flowpath at steady state operation. An additional entrance root axial fin is provided on the buckets to reduce the flow coefficient and afford further reduction in leakage flow.
    Type: Grant
    Filed: October 31, 2002
    Date of Patent: August 24, 2004
    Assignee: General Electric Company
    Inventors: Alison Carol Farrell, Douglas Carl Hofer, Norman Douglas Lathrop, Raymond Kenneth Overbaugh, Jr., William Thomas Parry, Kenneth James Robertson
  • Publication number: 20040126235
    Abstract: A method of modifying a rotor blade, and a rotor blade are provided. The rotor blade is for a steam turbine and it is modified to facilitate altering a natural vibratory frequency of the rotor blade, the rotor blade includes a leading edge, a trailing edge, a first sidewall, and a second sidewall, wherein the first and second sidewalls are connected axially at the leading and trailing edges, and the sidewalls extending radially between a rotor blade root to a rotor blade tip. The method includes determining a vibratory resonance condition of the rotor blade and forming a blade extension between the rotor blade root and the rotor blade tip that alters the determined resonance condition.
    Type: Application
    Filed: December 30, 2002
    Publication date: July 1, 2004
    Inventors: Kevin Joseph Barb, Amir Mujezinovic, Nicholas Francis Martin, Douglas Carl Hofer
  • Publication number: 20040091350
    Abstract: A diffuser includes an opening along the diffuser wall for preventing or delaying boundary layer separation of the main flow. The opening may include a curved passageway having a curvature convex relative to the main flow for utilizing the Coanda effect. A gas turbine may include the diffuser with an opening and a centerbody with an opening, each for providing a secondary flow of fluid into the diffuser. The gas turbine may direct fluid from an upstream turbine stage to the opening. A steam turbine may include the diffuser and may situate the opening downstream the diffuser inlet but upstream the location of boundary separation.
    Type: Application
    Filed: November 13, 2002
    Publication date: May 13, 2004
    Inventors: Paolo Graziosi, Richard Edwin Warren, Thomas Frank Fric, Ramani Mani, Douglas Carl Hofer
  • Publication number: 20040086379
    Abstract: The root region of a flowpath through a turbine includes a sealing configuration for minimizing leakage flow and secondary aerodynamic losses. Entrance and exit root radial seals are provided between upstream and downstream nozzles at locations radially inwardly of the root region of the flowpath to minimize radial leakage flow. To minimize intrusion flow into the flowpath from rotor pumping action and consequent aerodynamic losses, an exit flow guide on each bucket turns the exiting radial flow in a predominantly axial direction. Additionally, the upstream bucket root radius and nozzle root radius are faired or tapered to minimize the possibility of a protuberance projecting into the flowpath at steady state operation. An additional entrance root axial fin is provided on the buckets to reduce the flow coefficient and afford further reduction in leakage flow.
    Type: Application
    Filed: October 31, 2002
    Publication date: May 6, 2004
    Inventors: Alison Carol Farrell, Douglas Carl Hofer, Norman Douglas Lathrop, Raymond Kenneth Overbaugh, William Thomas Parry, Kenneth James Robertson
  • Publication number: 20040086375
    Abstract: The shafts of upstream and downstream turbines are interconnected by a coupling. A diffuser is provided in an intermediate cavity between the upstream and downstream turbines to recover kinetic energy, as well as minimize or eliminate windage and spinning losses resultant from exposure of the coupling to the flowpath along the turbines. A radial entry inlet provides a supplemental fluid admission into the intermediate cavity, the admission being turned axially and circumferentially for joining with the flow exiting the upstream turbine for combined flow to the downstream turbine.
    Type: Application
    Filed: November 6, 2002
    Publication date: May 6, 2004
    Inventors: Norman Douglas Lathrop, Daniel Mark Brown, Edward John Sharrow, Kristin Segreto, Douglas Carl Hofer
  • Publication number: 20020092190
    Abstract: Apparatus for measuring the trailing edge thickness of an airfoil in a turbine includes a plurality of tools; each tool having a main body portion and a forward end; an opening along a side edge and in proximity to a forward edge of the forward end, the opening including a slot of predetermined width adapted to engage the trailing edge of the airfoil; wherein each of the tools has a different predetermined slot width.
    Type: Application
    Filed: January 16, 2001
    Publication date: July 18, 2002
    Inventors: Douglas Carl Hofer, Nicholas Joseph Mollo, Alan Donn Maddaus, David Elliott Shapiro, Maurice D. Fournier
  • Patent number: 6375417
    Abstract: An improved moisture removal pocket configuration is described that includes an axial extension of the moisture removal slot over the bucket cover. The pocket may omit the upstream gutter segment to achieve the desired slot extension. The modified moisture removal pocket configuration improves the moisture removal efficiency by providing access to the pocket for water that moves as a film along the nozzle outer side wall and is entrained in the leakage jet above the bucket cover.
    Type: Grant
    Filed: July 12, 2000
    Date of Patent: April 23, 2002
    Assignee: General Electric Company
    Inventors: Douglas Carl Hofer, Nicholas Joseph Mollo, Alan Donn Maddaus