Patents by Inventor Ronald L. Shemet

Ronald L. Shemet 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).

  • Method and apparatus to monitor devices of a hydraulic circuit of an electro-mechanical transmission
    Patent number: 7670254
    Abstract: A method and an apparatus are provided to control operation of an electro-mechanical transmission device selectively operative in one of a plurality of fixed gear modes and two continuously variable modes. The method comprises controlling the flow control devices of the electro-hydraulic control circuit, and monitoring a plurality of pressure monitoring devices in the electro-hydraulic control circuit. A fault is identified in the electro-hydraulic control circuit when a signal output of one of the pressure monitoring devices does not correspond to an expected signal output for the pressure monitoring device after an elapsed time period.
    Type: Grant
    Filed: January 24, 2007
    Date of Patent: March 2, 2010
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Peter E. Wu, Thyagarajan Sadasiwan, Ronald L. Shemet
  • METHOD AND APPARATUS TO MONITOR DEVICES OF A HYDRAULIC CIRCUIT OF AN ELECTRO-MECHANICAL TRANSMISSION
    Publication number: 20080176709
    Abstract: A method and an apparatus are provided to control operation of an electro-mechanical transmission device selectively operative in one of a plurality of fixed gear modes and two continuously variable modes. The method comprises controlling the flow control devices of the electro-hydraulic control circuit, and monitoring a plurality of pressure monitoring devices in the electro-hydraulic control circuit. A fault is identified in the electro-hydraulic control circuit when a signal output of one of the pressure monitoring devices does not correspond to an expected signal output for the pressure monitoring device after an elapsed time period.
    Type: Application
    Filed: January 24, 2007
    Publication date: July 24, 2008
    Inventors: Peter E. Wu, Thyagarajan Sadasiwan, Ronald L. Shemet