Patents by Inventor Mark E. Zentgraf

Mark E. Zentgraf 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).

  • APPARATUS FOR FILLING AN OIL TANK
    Publication number: 20090101230
    Abstract: An apparatus for filling an oil tank may include one or more valves that may be arranged and/or sized in such a way as to assist in venting the oil tank during a fill operation and assure that the tank may be filled within a reasonable time.
    Type: Application
    Filed: October 19, 2007
    Publication date: April 23, 2009
    Inventors: Duane H. Anstead, Mark E. Zentgraf, Daniel Clautice, Charles R. Granitz, Joshua D. Smith, Mark Hopper