Patents by Inventor Kristina H. V. Hedengren

Kristina H. V. Hedengren 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: 5903147
    Abstract: An eddy current device for inspecting a component, such as a closed surface area of a gas turbine engine or the like, includes an eddy current array circuit having an active face for positioning on a surface portion of the component during an inspection operation and backing on a surface of the eddy current array circuit opposite to the active face. The eddy current array circuit and backing are disposed over the operating face and expandable sides of an extendible pin. The extendible pin has a slot formed therein with interior side edges which narrow toward the operating face of the pin at a predetermined slope. The expanding pin is positioned to cause the angled sides to mate while engaging the interior angled sides of the round or shaped hole to cause the exterior sides of the expandable pin to expand outwardly a greater distance as the pin is pushed deeper into the hole. This causes the eddy current circuit to conform with the shape of the surface to be inspected.
    Type: Grant
    Filed: March 18, 1997
    Date of Patent: May 11, 1999
    Assignee: General Electric Company
    Inventors: Carl Granger, Jr., Francis H. Little, Thomas B. Hewton, Kristina H. V. Hedengren
  • Patent number: 5611026
    Abstract: The present invention discloses a method and a system for supplementing and completing 3D CT data generated from an incomplete scanning path. If a detector is large enough to scan the object, additional data is acquired from adjacent scanning paths and combined directly with the original projection data set in order to form an exact and complete data set called the combined data set. If the object to be scanned is larger than the detector, additional data from adjacent scanning paths is acquired and reconstructed into an approximate image of the adjacent region from which appropriate projection data from the region of interest is calculated to form an exact and complete data set. In either case, a priori information about the object may be used to calculate missing projection information.
    Type: Grant
    Filed: July 10, 1995
    Date of Patent: March 11, 1997
    Assignee: General Electric Company
    Inventors: Jeffrey W. Eberhard, Kristina H. V. Hedengren
  • Patent number: 5463201
    Abstract: A seam-tracking apparatus for a welding system has a welding arm which directs an energy beam toward a seam. The seam-tracking apparatus includes an eddy current sensor formed by an array of eddy current elements, each producing a respective electrical signal when positioned adjacent to the seam to be tracked. An eddy current signal processor receives each respective electrical signal so as to generate position data indicative of the location of the seam. A controller is responsive to the position data so as to align the eddy current sensor and the welding arm over the seam so that the energy beam continuously impinges on the seam, as the welding arm advances along the seam. The eddy current sensor may be flexible, in which case the seam-tracking apparatus can track a seam between workpieces having curved surfaces.
    Type: Grant
    Filed: February 4, 1993
    Date of Patent: October 31, 1995
    Assignee: Generla Electric Company
    Inventors: Kristina H. V. Hedengren, Kenneth B. Haefner
  • Patent number: 5420429
    Abstract: Transducer arrays are constructed using multiple layers of transducer elements, each layer of transducer elements having energy passages such as spaces to allow free passage of energy to or from transducer elements in another layer. Each transducing element performs the same transducing (energy conversion) as the other transducing elements. The transducer arrays may be detector arrays having scintillation materials for detection of x-ray or other high energy rays with each element operable to detect the same type of energy (e.g., x-ray, gamma ray, ultrasound, etc.) as the other elements. Multiple layering of the detector elements allows construction of a diced or mosaic detector array without restrictions upon the thickness of the individual elements which might otherwise result from the kerf width.
    Type: Grant
    Filed: October 8, 1993
    Date of Patent: May 30, 1995
    Assignee: General Electric Company
    Inventors: Jeffrey W. Eberhard, Kristina H. V. Hedengren
  • Patent number: 5418457
    Abstract: A system and method is provided for aligning a scanning surface of an inspection probe relative to a workpiece surface under inspection. The probe preferably includes at least three alignment eddy current elements, each producing a respective spacing indication electrical signal in accordance with a spacing between each alignment eddy current element and the workpiece. The system further comprises processing means which receives each spacing-indication electrical signal so as to generate data indicative of the relative alignment between the scanning surface of the probe and the workpiece surface. A controller is responsive to the alignment data for aligning the probe such that in operation the scanning surface thereof is substantially parallel relative to the workpiece surface. The probe can include inspection eddy current elements, in which case the alignment and the inspection eddy current elements can be fabricated to form an integral eddy current inspection probe.
    Type: Grant
    Filed: March 12, 1993
    Date of Patent: May 23, 1995
    Assignee: General Electric Company
    Inventors: Kristina H. V. Hedengren, John D. Young
  • Patent number: 5389876
    Abstract: An eddy current probe array is disclosed comprising a plurality of spatially correlated eddy current probe elements sufficiently disposed within a flexible interconnecting structure to collect a discrete plurality of spatially correlated eddy current measurements for nondestructive near surface flaw detection. A plurality of precisely fabricated, substantially identical elements being sufficiently distributed can accommodate inspecting an area of conductor covered by the active width of the array in a single uni-directional scan. The array structure can flexibly conform to accommodate inspection of large, irregular, curved conductive surfaces which cannot be inspected by conventional means.
    Type: Grant
    Filed: May 6, 1991
    Date of Patent: February 14, 1995
    Assignee: General Electric Company
    Inventors: Kristina H. V. Hedengren, Richard O. McCary, Robert P. Alley, Richard J. Charles, William P. Kornrumpf, John D. Young
  • Patent number: 5371461
    Abstract: An improved eddy current probe array having means to compensate the entire array for varying different element liftoff, is described. An array consisting of a plurality of sense elements and means for compensating these sense elements is scanned across an inspection surface to produce respective scan responsive signals wherein the scan responsive signals of the sense elements are proportionately normalized or calibrated against the scan response of said compensating means during routine signal processing of the array signals in order to compensate for any lift off experienced by the sense elements. Array lift off compensation is attributable to sense element design cooperating with at least one lift off compensating sense element and a method of normalization/calibration performed during signal processing of the array signals.
    Type: Grant
    Filed: March 17, 1993
    Date of Patent: December 6, 1994
    Assignee: General Electric Company
    Inventor: Kristina H. V. Hedengren
  • Patent number: 5371462
    Abstract: Disclosed are methods for processing and interpreting data acquired from an eddy current probe array inspection system, based on a background subtraction technique. Test and reference waveform data sets are acquired, and subsequently combined. However, the data sets are first normalized and registered to the same position, registering on characteristic signals produced when scanning over edges. Specific techniques are disclosed for normalizing, correcting for spatial offsets, determining the actual locations of edge signals by peak detection and correlation, and adjusting for variations in the number of points in the test and reference data sets.
    Type: Grant
    Filed: March 19, 1993
    Date of Patent: December 6, 1994
    Assignee: General Electric Company
    Inventors: Kristina H. V. Hedengren, Patrick J. Howard
  • Patent number: 5345514
    Abstract: A method for inspecting a component of a gas turbine engine or the like having a plurality of similarly shaped structural portions, such as the gear teeth of a gear, the dovetail slots of a turbine disk or the like, includes the steps of: scanning a surface of at least one of the similarly shaped structural portions with an eddy current probe to induce eddy currents in the component; generating a two-dimensional image of the at least one portion from eddy current signals received during scanning, the image including a multiplicity of pixels arranged in a two-dimensional array and each pixel having a gray scale intensity responsive to the eddy current induced in the component at a component location corresponding to a position of the pixel in the matrix array; preprocessing the image to substantially reduce any signals or changes in the gray scale intensity of any pixels relative to the background pixel intensities of the image caused by geometrical characteristics and background noise common to all similarly
    Type: Grant
    Filed: September 16, 1991
    Date of Patent: September 6, 1994
    Assignee: General Electric Company
    Inventors: Yaghoub Mahdavieh, Kristina H. V. Hedengren
  • Patent number: 5319693
    Abstract: Relatively large objects are viewed using relatively small area detectors by changing the configurations corresponding to the relative positioning of a source of cone beam imaging energy, the object which is to be viewed, and the area detector. A relatively large area detector is simulated by use of a high quality, high resolution, relatively small area detector. The simulated area detector allows imaging of objects which are too wide and/or too high for an actual area detector. The different configurations may be realized by moving the actual area detector relative to the source or by repositioning the object relative to the area detector. Movement for reconfiguration may be in a plane parallel to a plane in which a scan path is disposed if the object is too wide. If the object is too high, the reconfiguration movement would be perpendicular to a plane in which a scan path, usually circular, is located.
    Type: Grant
    Filed: December 30, 1992
    Date of Patent: June 7, 1994
    Assignee: General Electric Company
    Inventors: Jeffrey W. Eberhard, Kwok C. Tam, Kristina H. V. Hedengren
  • Patent number: 5315234
    Abstract: An eddy current device for inspecting a component includes an eddy current array circuit having respective pluralities of drive and sense elements and having an active face for positioning on a surface of the component during the inspection operation. A backing is disposed on a face of the eddy current array circuit opposite to the active face for concentrating an electromagnetic flux from the eddy current array circuit into the component when each of the plurality of drive elements is being energized. A mechanical arrangement is provided for supporting and deploying the backing and the array circuit to substantially conform with the surface portion under inspection and to cause each of the pluralities of drive and sense elements to be maintained at their respective substantially constant distances from the inspection surface during scanning, preferably at a controlled rate of scan.
    Type: Grant
    Filed: April 3, 1992
    Date of Patent: May 24, 1994
    Assignee: General Electric Company
    Inventors: George H. Sutton, Jr., Francis H. Little, Kristina H. V. Hedengren, Richard J. Charles, William P. Kornrumpf, Donna C. Hurley
  • Patent number: 5278884
    Abstract: Complete CT data acquisition is provided by scanning path trajectories located on a sphere or approximately located on a sphere. The scanning path trajectories are at least bounded between two relatively close spheres. The various scanning paths include sinusoids, square waves, circles, and arcs.
    Type: Grant
    Filed: December 18, 1992
    Date of Patent: January 11, 1994
    Assignee: General Electric Company
    Inventors: Jeffrey W. Eberhard, Kristina H. V. Hedengren
  • Patent number: 5262722
    Abstract: An apparatus for near surface, nondestructive eddy current scanning of a conductive part using a multi-layer eddy current probe array. Such structures of this type, generally, employ an ultra-thin, flexible, film-like, multi-layer eddy current probe array which is adapted to provide routine inspection of conductive parts while also providing improved signal integrity, signal transmission and isolation.
    Type: Grant
    Filed: April 3, 1992
    Date of Patent: November 16, 1993
    Assignee: General Electric Company
    Inventors: Kristina H. V. Hedengren, Richard J. Charles, William P. Kornrumpf
  • Patent number: 5237271
    Abstract: A method for improving eddy current flaw detection by simultaneously exciting a select plurality of eddy current probe elements with a multiplicity of select frequencies in a simultaneous parallel or serial manner to form a corresponding multiplicity of direct and/or differential images which can be processed together for improved eddy current image resolution. Select eddy current probe elements when driven at select multiple frequencies further provide a capability for simultaneous flaw detection and characterization by dual resolution scanning. Dual flaw resolution is accomplished by first locating a flaw using low resolution frequencies; and thereupon, switching to higher resolution frequencies to characterize the flaw.
    Type: Grant
    Filed: May 6, 1991
    Date of Patent: August 17, 1993
    Assignee: General Electric Company
    Inventor: Kristina H. V. Hedengren
  • Patent number: 5073910
    Abstract: A configuration for three-dimensional cone beam computerized tomography imaging which allows a complete data set to be acquired in a practical manner, while providing fast data acquisition to minimize motion artifacts. An object within a field of view such that every plane passing through the field of view passes through the source scanning trajectory at least once.
    Type: Grant
    Filed: August 27, 1990
    Date of Patent: December 17, 1991
    Assignee: General Electric Company
    Inventors: Jeffrey W. Eberhard, Kristina H. V. Hedengren
  • Patent number: 5006800
    Abstract: A phase-difference eddy current imaging system has a bridge circuit including a pair of coils with one or both coils disposed proximate an object that may contain one or more flaws. An oscillator is coupled to the bridge circuit and also to a pair of phase detectors that are coupled to the coils. A differential amplifier is coupled to the phase detectors for providing a comparison signal. A method for eddy current imaging using phase difference detection comprises providing relative movement between an object and at least one of a pair of coils, measuring the phase of the effective reactance in each of the coils, comparing the measured values, and formatting the compared values as a function of spatial position.
    Type: Grant
    Filed: November 6, 1989
    Date of Patent: April 9, 1991
    Assignee: General Electric Company
    Inventors: Kristina H. V. Hedengren, Donna C. Hurley, John D. Young
  • Patent number: 4803639
    Abstract: An X-ray inspection system for manually or automatically performing digital fluoroscopy inspections and/or computed tomography inspections by X-ray examination of manufactured parts incorporates a computer system which automatically analyzes the inspected parts for flaws. The system includes apparatus for automatically positioning the parts in an X-ray machine for obtaining fluoroscopy and tomography views of the part and for acquiring data from the inspections at production rates. The system automatically identifies the location of rejectable flaws in the parts during the fluoroscopy scanning and subsequently identifies those locations for obtaining tomography scans, if the identified flaw location is questionable. The system can automatically reject parts containing flaws identified during the fluoroscopy inspections. This system operates in a real-time environment by providing analysis of one part while a subsequent part is being subjected to X-ray examination.
    Type: Grant
    Filed: February 25, 1986
    Date of Patent: February 7, 1989
    Assignee: General Electric Company
    Inventors: Douglas S. Steele, Larry C. Howington, James W. Schuler, Joseph J. Sostarich, Charles R. Wojciechowski, Theodore W. Sippel, Joseph M. Portaz, Ralph G. Isaacs, Henry J. Scudder, III, Thomas G. Kincaid, Kristina H. V. Hedengren, Rudolph A. A. Koegl, John P. Keaveney, Joseph Czechowski, III, John R. Brehm, James M. Brown, Jr., David W. Oliver, George E. Williams, Richard D. Miller