Patents by Inventor Fritz T. Pfannkuche

Fritz T. Pfannkuche 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).

  • Patent number: 4230192
    Abstract: Coring apparatus for obtaining core samples which may comprise: an outer barrel assembly, the lower end of which is adapted for connection to a core bit, the upper end of which is adapted for connection to a drill string; an inner barrel assembly concentrically disposed within the outer barrel assembly and having first and second axially spaced and fluid communicating chambers therein; and valve means carried by the inner barrel assembly and movable from an open position, in which a core sample may be received by the first chamber, to a closed position, sealingly enclosing the core sample within the first chamber.
    Type: Grant
    Filed: August 8, 1978
    Date of Patent: October 28, 1980
    Inventor: Fritz T. Pfannkuche