Patents by Inventor Matt Shoffner

Matt Shoffner 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: 6062322
    Abstract: A down-the-hole percussive drill comprises a casing, a drill bit mounted at a lower end of the casing, a hollow feed tube fixed within the casing and extending along a center axis thereof, and a piston mounted for axial reciprocation within the casing for transmitting impacts to the drill bit. The piston has a stepped configuration in that a lower portion thereof is of smaller outer diameter than an upper portion thereof. The upper portion forms a downwardly facing surface at the junction between the upper and lower portions. Air-conducting passages are formed in the upper portion of the piston and are supplied with pressurized air from the hollow feed tube. One of those passages intersects the downwardly facing surface of the upper portion of the piston. The hollow feed tube is mounted to a top sub of the drill by pins which are mounted in the top sub and extend radially into a sidewall of the feed tube, the pins being situated outside of the central passage.
    Type: Grant
    Filed: June 15, 1998
    Date of Patent: May 16, 2000
    Assignee: Sandvik AB
    Inventors: Rainer Beccu, Matt Shoffner, Kenneth Ahlhorn