Patents by Inventor Charles E. Duffer

Charles E. Duffer 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: 10466206
    Abstract: A ferromagnetic strip sensor for use in magnetostrictive testing of various structures. In its simplest form, the sensor has a ferromagnetic strip with an electrical coil winding. A permanent magnet is positioned atop the strip, aligned with but offset from, a center axis of the strip. The sensor is operable such that a time varying current in the coil results in a unidirectional guided wave. This guided wave travels within the structure, and is reflected from anomalies in the structure.
    Type: Grant
    Filed: December 12, 2016
    Date of Patent: November 5, 2019
    Assignee: Southwest Research Institute
    Inventors: Sergey A. Vinogradov, Glenn M. Light, Charles E. Duffer
  • Publication number: 20180164256
    Abstract: A ferromagnetic strip sensor for use in magnetostrictive testing of various structures. In its simplest form, the sensor has a ferromagnetic strip with an electrical coil winding. A permanent magnet is positioned atop the strip, aligned with but offset from, a center axis of the strip. The sensor is operable such that a time varying current in the coil results in a unidirectional guided wave. This guided wave travels within the structure, and is reflected from anomalies in the structure.
    Type: Application
    Filed: December 12, 2016
    Publication date: June 14, 2018
    Inventors: Sergey A. Vinogradov, Glenn M. Light, Charles E. Duffer
  • Patent number: 9714922
    Abstract: A probe for use in magnetostrictive testing of tubular structures. The probe has a handle and an outer tube, the latter having an expandable probe head for insertion into the tubular structure. A pair of magnetostrictive sensors is mounted in or on the probe head. A flexible bladder is located inside the outer tube in the area of the probe head, and communicates with a pressurizing cartridge in the probe handle via a bladder tube. The bladder is operable to expand, causing the probe head to expand, which moves the sensors toward the inner wall of the tubular structure. The probe is also equipped with a couplant injector that delivers coupling fluid to any gaps between the inner surface of the tubular structure and the outer surface of the probe.
    Type: Grant
    Filed: October 27, 2015
    Date of Patent: July 25, 2017
    Assignee: SOUTHWEST RESEARCH INSTITUTE
    Inventors: Sergey A. Vinogradov, Charles E. Duffer, Glenn M. Light
  • Publication number: 20170115204
    Abstract: A probe for use in magnetostrictive testing of tubular structures. The probe has a handle and an outer tube, the latter having an expandable probe head for insertion into the tubular structure. A pair of magnetostrictive sensors is mounted in or on the probe head. A flexible bladder is located inside the outer tube in the area of the probe head, and communicates with a pressurizing cartridge in the probe handle via a bladder tube. The bladder is operable to expand, causing the probe head to expand, which moves the sensors toward the inner wall of the tubular structure. The probe is also equipped with a couplant injector that delivers coupling fluid to any gaps between the inner surface of the tubular structure and the outer surface of the probe.
    Type: Application
    Filed: October 27, 2015
    Publication date: April 27, 2017
    Inventors: Sergey A. Vinogradov, Charles E. Duffer, Glenn M. Light
  • Patent number: 8653810
    Abstract: A flexible printed circuit board (PCB) magnetostrictive (MS) sensor comprising a first direct current (DC) bias PCB layer comprising a first plurality of conductive traces, a first alternating current (AC) PCB layer disposed on the first DC bias PCB layer, the first AC PCB layer comprising a first AC coil, a pocket PCB layer disposed on the first AC PCB layer, the pocket PCB layer to receive a strip of MS material, a second AC PCB layer disposed on the pocket PCB layer, the second AC PCB layer comprising a second AC coil, and a second DC bias PCB layer disposed on the second AC PCB layer, the second DC bias PCB layer comprising a second plurality of conductive traces. The traces from the first plurality of conductive traces are electrically coupled to traces from the second plurality of conductive traces.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: February 18, 2014
    Assignee: Southwest Research Institute
    Inventors: Adam C. Cobb, Jonathan D. Bartlett, Charles E. Duffer
  • Patent number: 8624589
    Abstract: An ultrasonic probe that uses the magnetostrictive effect to generate and detect a surface-coupled guided wave for the purpose of inspecting a thick-walled structure for surface defects. A transmitter sensor and a receiver sensor are especially designed to generate and detect short wavelengths that will couple to only one surface of the plate.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: January 7, 2014
    Assignee: Southwest Research Institute
    Inventors: Alan R. Puchot, Charles E. Duffer, Sang Y. Kim, Adam C. Cobb, Pavan K. Shukla
  • Publication number: 20130069639
    Abstract: A flexible printed circuit board (PCB) magnetostrictive (MS) sensor comprising a first direct current (DC) bias PCB layer comprising a first plurality of conductive traces, a first alternating current (AC) PCB layer disposed on the first DC bias PCB layer, the first AC PCB layer comprising a first AC coil, a pocket PCB layer disposed on the first AC PCB layer, the pocket PCB layer to receive a strip of MS material, a second AC PCB layer disposed on the pocket PCB layer, the second AC PCB layer comprising a second AC coil, and a second DC bias PCB layer disposed on the second AC PCB layer, the second DC bias PCB layer comprising a second plurality of conductive traces. The traces from the first plurality of conductive traces are electrically coupled to traces from the second plurality of conductive traces.
    Type: Application
    Filed: September 19, 2011
    Publication date: March 21, 2013
    Applicant: Southwest Research Institute
    Inventors: Adam C. COBB, Jonathan D. BARTLETT, Charles E. DUFFER
  • Publication number: 20110221428
    Abstract: An ultrasonic probe that uses the magnetostrictive effect to generate and detect a surface-coupled guided wave for the purpose of inspecting a thick-walled structure for surface defects. A transmitter probe and a receiver probe are especially designed to generate and detect short wavelengths that will couple to only one surface of the plate.
    Type: Application
    Filed: January 14, 2011
    Publication date: September 15, 2011
    Applicant: Southwest Research Institute
    Inventors: Alan R Puchot, Charles E. DUFFER, Sang Y. KIM, Adam C. COBB, Pavan K. SHUKLA
  • Patent number: 6188050
    Abstract: A system for controlling process temperatures for semi-conductor wafers comprises a heater to heat the wafer, an element to generate a plurality of ultrasonic vibrations in the wafer, a Sagnac interferometer adapted to sense the ultrasonic vibrations and generate a wafer temperature signal responsive thereto, a system to calculate the wafer temperature on the basis of the generated wafer temperature signal, and a control element the wafer heater on the basis of the calculated wafer temperature.
    Type: Grant
    Filed: December 8, 1999
    Date of Patent: February 13, 2001
    Assignee: Karta Technologies, Inc.
    Inventors: Charles E. Duffer, Jorge J. Alcoz