Patents by Inventor John D. Bothum

John D. Bothum 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).

  • Spade-type drill bit apparatus and method
    Patent number: 5291806
    Abstract: A spade-type drill bit is disclosed having a shank portion and a spade bit portion extending from the shank portion. The spade bit portion includes a spade portion with a planar region, and a center tip concentric with a longitudinal axis and extending from the spade portion. First and second radial cutting edges extend from the center tip toward first and second corner tips. First and second longitudinal cutting edges extend along longitudinal sides of the spade portion and terminate at the first and second corner tips. The first and second corner tips are located forward of the plane of the spade portion in the direction of rotation of the drill bit. The first and second radial cutting edges, and the first and second longitudinal cutting edges further include curved portions adjacent each of the first and second corner tips. Threads may also be provided on the center tip.
    Type: Grant
    Filed: June 14, 1993
    Date of Patent: March 8, 1994
    Assignee: Enderes Tool Company, Inc.
    Inventor: John D. Bothum
  • Spade-type drill bit apparatus and method
    Patent number: 5221166
    Abstract: A spade-type drill bit is disclosed having a shank portion and a spade bit portion extending from the shank portion. The spade bit portion includes a spade portion with a planar region, and a center tip concentric with a longitudinal axis and extending from the spade portion. First and second radial cutting edges extend from the center tip toward first and second corner tips. First and second longitudinal cutting edges extend along longitudinal sides of the spade portion and terminate at the first and second corner tips. The first and second corner tips are located forward of the plane of the spade portion in the direction of rotation of the drill bit. The first and second radial cutting edges, and the first and second longitudinal cutting edges further include curved portions adjacent each of the first and second corner tips. Threads may also be provided on the center tip.
    Type: Grant
    Filed: July 31, 1991
    Date of Patent: June 22, 1993
    Assignee: Enderes Tool Co., Inc.
    Inventor: John D. Bothum