Patents by Inventor Cheol S. Lee

Cheol S. Lee 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).

  • Air-fuel imbalance detection based on zero-phase filtering
    Patent number: 7900615
    Abstract: A control system comprising an oxygen sensor that generates an oxygen signal based on an oxygen concentration level in an exhaust gas of an engine, a filtering module that determines a filtered signal based on the oxygen signal, and an air-fuel imbalance detection module that detects an air-fuel imbalance in the engine based on the oxygen signal and the filtered signal. A method comprising generating an oxygen signal based on an oxygen concentration level in an exhaust gas of an engine, determining a filtered signal based on the oxygen signal, and detecting an air-fuel imbalance in the engine based on the oxygen signal and the filtered signal.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: March 8, 2011
    Inventors: Zhong Wang, Lan Wang, Ian J. Mac Ewen, Igor Anilovich, Steven Ward Majors, Cheol S. Lee
  • AIR-FUEL IMBALANCE DETECTION BASED ON ZERO-PHASE FILTERING
    Publication number: 20100077728
    Abstract: A control system comprising an oxygen sensor that generates an oxygen signal based on an oxygen concentration level in an exhaust gas of an engine, a filtering module that determines a filtered signal based on the oxygen signal, and an air-fuel imbalance detection module that detects an air-fuel imbalance in the engine based on the oxygen signal and the filtered signal. A method comprising generating an oxygen signal based on an oxygen concentration level in an exhaust gas of an engine, determining a filtered signal based on the oxygen signal, and detecting an air-fuel imbalance in the engine based on the oxygen signal and the filtered signal.
    Type: Application
    Filed: October 1, 2008
    Publication date: April 1, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Zhong Wang, Lan Wang, Ian J. Mac Ewen, Igor Anilovich, Steven Ward Majors, Cheol S. Lee