Patents by Inventor Robert W. Cummings

Robert W. Cummings 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).

  • Refrigerant loss detection
    Patent number: 6330802
    Abstract: A method for detecting a low level of refrigerant circulating through a motor vehicle refrigerant circuit having a compressor (12), a condenser (14), an evaporator (16), and an accumulator (18), includes detecting a partial loss of a refrigerant fluid by measuring the temperature difference of the refrigerant fluid between an evaporator inlet and an evaporator outlet. The method further includes detecting a complete loss of refrigerant by measuring the pressure of the refrigerant in the liquid phase between the condenser (14) and the evaporator (16). The temperature and pressure measurements are converted to engineering units and then compared to predetermined engineering units that correspond to separate ranges of ambient temperatures for determining the if the refrigerant level is low.
    Type: Grant
    Filed: February 22, 2000
    Date of Patent: December 18, 2001
    Assignee: Behr Climate Systems, Inc.
    Inventors: Robert W. Cummings, Thien D. Ta