Patents by Inventor David Letter

David Letter 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: 10281712
    Abstract: Internal components of power generation machinery, such as gas turbine engines, are inspected with a spherical, optical-camera inspection system, mounted within a camera housing on a distal end of a compact diameter, single-axis inspection scope. The inspection scope includes nested, non-rotatable telescoping tubes, which define an extension axis. Circumscribing, telescoping tubes have anti-rotation collars, which are in sliding engagement with extension tracks on a circumferential surface of an opposing, nested tube, for ease of extension and retraction of the camera during visual inspections of power generation machinery. The camera is advanced and/or retracted along a scope extension axis by nested, drive tubes, which incorporate at least one external drive screw on a circumscribed drive tube and corresponding female threads formed in a circumscribing drive tube. The spherical camera has a 360-degree field of view, and captures images without rotation about the scope extension axis.
    Type: Grant
    Filed: April 21, 2017
    Date of Patent: May 7, 2019
    Assignee: SIEMENS ENERGY, INC.
    Inventors: David Letter, Isaac Piersall, Clifford Hatcher, Jr.
  • Patent number: 10274718
    Abstract: Internal components of power generation machinery, such as gas turbine engines, are inspected with a spherical, optical-camera inspection system, mounted within a camera housing on a distal end of a compact diameter, single-axis inspection scope. The inspection scope includes nested, non-rotatable telescoping tubes, which define an extension axis. Circumscribing, telescoping tubes have anti-rotation collars, which are in sliding engagement with extension tracks on a circumferential surface of an opposing, nested tube, for ease of extension and retraction of the camera during visual inspections of power generation machinery. The camera is advanced and/or retracted along a scope extension axis by nested, drive tubes, which incorporate at least one external drive screw on a circumscribed drive tube and corresponding female threads formed in a circumscribing drive tube. The spherical camera has a 360-degree field of view, and captures images without rotation about the scope extension axis.
    Type: Grant
    Filed: April 21, 2017
    Date of Patent: April 30, 2019
    Assignee: SIEMENS ENERGY, INC.
    Inventors: David Letter, Isaac Piersall, Clifford Hatcher, Jr.
  • Patent number: 10189045
    Abstract: A blackbody material application system for a turbine. The system includes a blackbody material supply and a moveable hose connected to the blackbody material supply wherein the hose sprays blackbody material onto a selected area within the turbine. The system also includes a rotatable bracket that holds the hose, wherein rotation of the bracket moves the hose toward the selected area within the turbine to enable application of the blackbody material onto the selected area. In addition, the system includes a motor for rotating the bracket and a moveable arm that holds the bracket wherein the bracket is inserted through an opening in the turbine and movement of the arm enables positioning of the bracket and hose in relative close proximity to the selected area suitable for spraying blackbody material onto the selected area.
    Type: Grant
    Filed: August 31, 2016
    Date of Patent: January 29, 2019
    Assignee: SIEMENS ENERGY, INC.
    Inventors: Dustin C. Boudin, Clifford Hatcher, Jr., Anand A. Kulkarni, Kevin Licata, David Letter, Alejandro Bancalari
  • Patent number: 10041371
    Abstract: A robotically articulated inspection scope (56, 69) inserted into a pilot fuel nozzle port (58) of a turbine engine (20) for in-situ measurement of gaps (59) between tips of turbine blades (40A) and the surrounding shroud (44). A non-contact gap measuring device (52) on a distal end (79) of the scope may be navigated through a combustor (28) and transition duct (34) into a position proximate a blade tip gap. The scope may be controlled via computer (68) via a robotic drive (66) affixed to the pilot fuel nozzle port. Multiple scopes may be used to measure gaps (59A-D) at multiple azimuths of the turbine simultaneously. The turbine disk (37) may be rotated on its operating turning gear to sequentially measure each blade at each azimuth. The computer may memorize an interactively navigated path for subsequent automated positioning.
    Type: Grant
    Filed: February 6, 2015
    Date of Patent: August 7, 2018
    Assignee: SIEMENS ENERGY, INC.
    Inventors: Joshua DeAscanis, David Letter, Alejandro Bancalari, Clifford Hatcher, Jr.
  • Publication number: 20180209296
    Abstract: A robotically articulated inspection scope (56, 69) inserted into a pilot fuel nozzle port (58) of a turbine engine (20) for in-situ measurement of gaps (59) between tips of turbine blades (40A) and the surrounding shroud (44). A non-contact gap measuring device (52) on a distal end (79) of the scope may be navigated through a combustor (28) and transition duct (34) into a position proximate a blade tip gap. The scope may be controlled via computer (68) via a robotic drive (66) affixed to the pilot fuel nozzle port. Multiple scopes may be used to measure gaps (59A-D) at multiple azimuths of the turbine simultaneously. The turbine disk (37) may be rotated on its operating turning gear to sequentially measure each blade at each azimuth. The computer may memorize an interactively navigated path for subsequent automated positioning.
    Type: Application
    Filed: February 6, 2015
    Publication date: July 26, 2018
    Inventors: Joshua DeAscanis, David Letter, Alejandro Bancalari, Clifford Hatcher, Jr.
  • Patent number: 9948835
    Abstract: Internal components of power generation machinery, such as gas turbine engines, are inspected with a spherical optical camera inspection system mounted on a compact diameter, single-axis inspection scope that is capable of insertion within an inspection port or other accessible insertion site. The inspection scope includes nested, non-rotatable telescoping tubes, which define an extension axis. Circumscribing, telescoping tubes have anti-rotation collars, which are in sliding engagement with a mating axial groove on an outer circumferential surface of a circumscribed tube. The camera is advanced and/or retracted along a scope extension axis by nested, drive tubes, which incorporate at least one external drive screw on a circumscribed drive tube and corresponding female threads formed in a circumscribing drive tube. The spherical camera has a 360-degree field of view, and captures images without rotation about the scope extension axis.
    Type: Grant
    Filed: July 18, 2016
    Date of Patent: April 17, 2018
    Assignee: SIEMENS ENERGY, INC.
    Inventors: Joshua DeAscanis, David Letter, Isaac Piersall, Clifford Hatcher, Jr.
  • Publication number: 20180056315
    Abstract: A blackbody material application system for a turbine. The system includes a blackbody material supply and a moveable hose connected to the blackbody material supply wherein the hose sprays blackbody material onto a selected area within the turbine. The system also includes a rotatable bracket that holds the hose, wherein rotation of the bracket moves the hose toward the selected area within the turbine to enable application of the blackbody material onto the selected area. In addition, the system includes a motor for rotating the bracket and a moveable arm that holds the bracket wherein the bracket is inserted through an opening in the turbine and movement of the arm enables positioning of the bracket and hose in relative close proximity to the selected area suitable for spraying blackbody material onto the selected area.
    Type: Application
    Filed: August 31, 2016
    Publication date: March 1, 2018
    Inventors: Dustin C. Boudin, Clifford Hatcher, JR., Anand A. Kulkarni, Kevin Licata, David Letter, Alejandro Bancalari
  • Patent number: 9778141
    Abstract: Non-destructive evaluation optical inspection systems include video cameras or other reflective-photonic optical instruments, such as laser profilometers or 3D white light laser dimensional scanners, which are incorporated in a camera head. The camera head is coupled to a distal end of a self-supporting and shape-retaining elongate deformable deployment tether. The deployment tether is bendable, for insertion through cavities of power generation machines and orientation of the camera head field of view on the internal area of interest. The deployment tether is capable of being deformed repeatedly, for inspection of different areas of interest. In some embodiments, interchangeable camera heads are selectively coupled to the deployment tether, so that a kit or family of different optical inspection instruments are available to carry out multiple types of inspections within a single or multiple types of power generation machinery.
    Type: Grant
    Filed: July 20, 2015
    Date of Patent: October 3, 2017
    Assignee: Siemens Energy, Inc.
    Inventors: Alejandro Bancalari, Clifford Hatcher, Jr., Forrest R. Ruhge, James P. Williams, Joshua DeAscanis, David Letter, Robert G. Shannon
  • Publication number: 20170219814
    Abstract: Internal components of power generation machinery, such as gas turbine engines, are inspected with a spherical, optical-camera inspection system, mounted within a camera housing on a distal end of a compact diameter, single-axis inspection scope. The inspection scope includes nested, non-rotatable telescoping tubes, which define an extension axis. Circumscribing, telescoping tubes have anti-rotation collars, which are in sliding engagement with extension tracks on a circumferential surface of an opposing, nested tube, for ease of extension and retraction of the camera during visual inspections of power generation machinery. The camera is advanced and/or retracted along a scope extension axis by nested, drive tubes, which incorporate at least one external drive screw on a circumscribed drive tube and corresponding female threads formed in a circumscribing drive tube. The spherical camera has a 360-degree field of view, and captures images without rotation about the scope extension axis.
    Type: Application
    Filed: April 21, 2017
    Publication date: August 3, 2017
    Inventors: David Letter, Isaac Piersall, Clifford Hatcher, JR.
  • Publication number: 20170219815
    Abstract: Internal components of power generation machinery, such as gas turbine engines, are inspected with a spherical, optical-camera inspection system, mounted within a camera housing on a distal end of a compact diameter, single-axis inspection scope. The inspection scope includes nested, non-rotatable telescoping tubes, which define an extension axis. Circumscribing, telescoping tubes have anti-rotation collars, which are in sliding engagement with extension tracks on a circumferential surface of an opposing, nested tube, for ease of extension and retraction of the camera during visual inspections of power generation machinery. The camera is advanced and/or retracted along a scope extension axis by nested, drive tubes, which incorporate at least one external drive screw on a circumscribed drive tube and corresponding female threads formed in a circumscribing drive tube. The spherical camera has a 360-degree field of view, and captures images without rotation about the scope extension axis.
    Type: Application
    Filed: April 21, 2017
    Publication date: August 3, 2017
    Inventors: David Letter, Isaac Piersall, Clifford Hatcher, JR.
  • Patent number: 9709463
    Abstract: Internal components of power generation machines, such as gas or steam turbines, are inspected with a laser profilometer inspection system that is inserted and positioned within the turbine, for example through an inspection port that is in communication with an open inter-row spacing volume between an opposing turbine vane and turbine blade row. Component surface profile scans are performed to determine relative profile heights along a two-dimensional scan line generated by the profilometer. Three-dimensional profile information is obtained by translating the scan line across the surface. Real time profile information is gathered without physical contact, which is helpful for extracting off-line engineering information about component surface conditions, including surface spallation, perforation, and gaps between components. The system is capable of determining blade tip gap between a turbine blade tip and its opposing abradable surface in the turbine casing.
    Type: Grant
    Filed: June 8, 2015
    Date of Patent: July 18, 2017
    Assignee: Siemens Energy, Inc.
    Inventors: Joshua DeAscanis, Clifford Hatcher, Jr., David Letter
  • Publication number: 20160330351
    Abstract: Internal components of power generation machinery, such as gas turbine engines, are inspected with a spherical optical camera inspection system mounted on a compact diameter, single-axis inspection scope that is capable of insertion within an inspection port or other accessible insertion site. The inspection scope includes nested, non-rotatable telescoping tubes, which define an extension axis. Circumscribing, telescoping tubes have anti-rotation collars, which are in sliding engagement with a mating axial groove on an outer circumferential surface of a circumscribed tube. The camera is advanced and/or retracted along a scope extension axis by nested, drive tubes, which incorporate at least one external drive screw on a circumscribed drive tube and corresponding female threads formed in a circumscribing drive tube. The spherical camera has a 360-degree field of view, and captures images without rotation about the scope extension axis.
    Type: Application
    Filed: July 18, 2016
    Publication date: November 10, 2016
    Inventors: Joshua DeAscanis, David Letter, Isaac Piersall, Clifford Hatcher, JR.
  • Publication number: 20150338353
    Abstract: Non-destructive evaluation optical inspection systems include video cameras or other reflective-photonic optical instruments, such as laser profilometers or 3D white light laser dimensional scanners, which are incorporated in a camera head. The camera head is coupled to a distal end of a self-supporting and shape-retaining elongate deformable deployment tether. The deployment tether is bendable, for insertion through cavities of power generation machines and orientation of the camera head field of view on the internal area of interest. The deployment tether is capable of being deformed repeatedly, for inspection of different areas of interest. In some embodiments, interchangeable camera heads are selectively coupled to the deployment tether, so that a kit or family of different optical inspection instruments are available to carry out multiple types of inspections within a single or multiple types of power generation machinery.
    Type: Application
    Filed: July 20, 2015
    Publication date: November 26, 2015
    Inventors: Alejandro Bancalari, Clifford Hatcher, JR., Forrest R. Ruhge, James P. Williams, Joshua DeAscanis, David Letter, Robert G. Shannon
  • Publication number: 20150300920
    Abstract: Internal components of power generation machines, such as gas or steam turbines, are inspected with a laser profilometer inspection system that is inserted and positioned within the turbine, for example through an inspection port that is in communication with an open inter-row spacing volume between an opposing turbine vane and turbine blade row. Component surface profile scans are performed to determine relative profile heights along a two-dimensional scan line generated by the profilometer. Three-dimensional profile information is obtained by translating the scan line across the surface. Real time profile information is gathered without physical contact, which is helpful for extracting off-line engineering information about component surface conditions, including surface spallation, perforation, and gaps between components. The system is capable of determining blade tip gap between a turbine blade tip and its opposing abradable surface in the turbine casing.
    Type: Application
    Filed: June 8, 2015
    Publication date: October 22, 2015
    Inventors: Joshua DeAscanis, Clifford Hatcher, JR., David Letter