Patents by Inventor David Cowell

David Cowell 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).

  • Voice Verification System
    Publication number: 20120253809
    Abstract: A voice verification module 308, for example for an interactive voice response system, is disclosed. The voice verification module 308 is configured to select from a store 310 of verification words one or more verification words responsive to a request for a verification phrase and form a verification phrase including said one or more verification words distributed throughout said verification phrase.
    Type: Application
    Filed: March 26, 2012
    Publication date: October 4, 2012
    Applicant: BIOMETRIC SECURITY LTD
    Inventors: Trevor Thomas, Nicholas Wise, David Cowell
  • High voltage protection circuit for x-ray systems
    Patent number: 4408247
    Abstract: A circuit protects a high voltage supply for x-ray tubes from the damaging effects of a tube flashover or the like. The circuit monitors line current, and high voltage and reacts to an increase in line current occurring with a corresponding drop in high voltage to turn off the high voltage.
    Type: Grant
    Filed: September 10, 1980
    Date of Patent: October 4, 1983
    Assignee: Sybron Corporation
    Inventor: David Cowell
  • Power supply for triode x-ray tubes
    Patent number: 4378501
    Abstract: A power supply provides high voltage for a grid controlled x-ray tube. In the supply an oscillator generates a high frequency signal which is amplified and transformed to kilovoltage. A voltage multiplier increases the kilovoltage to a potential suitable for the tube. The voltage multiplier includes a bank of series capacitors which tends to maintain a constant high voltage when the tube is not conducting.
    Type: Grant
    Filed: January 5, 1981
    Date of Patent: March 29, 1983
    Assignee: Sybron Corporation
    Inventor: David Cowell
  • Preheat circuit for X-ray tubes
    Patent number: 4191889
    Abstract: A circuit for use with a X-ray tube applies filament power to preheat the tube prior to the application of high voltage. The preheat duration is made to be in inverse relation to the line voltage. The desired result is when the tube starts to conduct the tube current and tube voltage is held within acceptable limits regardless of line voltage variations.
    Type: Grant
    Filed: December 5, 1977
    Date of Patent: March 4, 1980
    Assignee: Sybron Corporation
    Inventor: David Cowell
  • X-ray detector for a panoramic X-ray device
    Patent number: 3932756
    Abstract: An X-ray detector for converting X-ray energy into electrical energy which contains a X-ray sensitive fluorescent screen optically coupled to a photovoltaic energy conversion cell. An electrostatic shield is provided at the input of said fluorescent screen to shield the detector from both background electrical noise and ambient light. Mechanical configurations and electrical flexibility make the detector particularly well suited for the control of panoramic X-ray machines.
    Type: Grant
    Filed: June 24, 1974
    Date of Patent: January 13, 1976
    Assignee: Sybron Corporation
    Inventors: David Cowell, Frieder H. Ensslin