Patents by Inventor Marshall D. Ketchum

Marshall D. Ketchum 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).

  • Device for monitoring dissolved gases in electrical insulating liquids such as transformer oils
    Patent number: 4236404
    Abstract: A device to monitor dissolved gases in electrical insulating liquids such as transformer oils. The monitoring device includes a sampling means to obtain a liquid sample from the electrical device whose liquid is being monitored, a gas extraction means to extract the dissolved gases from the liquid sample, an injection means to inject the extracted gases into a gas chromatograph, and a gas chromatograph to analyze the dissolved gases to determine the concentration of various dissolved gases.
    Type: Grant
    Filed: August 31, 1976
    Date of Patent: December 2, 1980
    Assignee: General Electric Company
    Inventors: Marshall D. Ketchum, Alexander J. Yerman