Patents by Inventor Derrick Merrill

Derrick Merrill 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).

  • Annular hole cutter
    Patent number: 5246318
    Abstract: A tipped annular hole cutter is made by brazing all the cutting tips (30) simultaneously to the cylindrical wall (12) of the cutter body. The tips (30) have outer and inner lands (32, 34) which locate against the outer and inner surfaces (52, 54) of the cylindrical wall (12). This accurately locates the tips radially during brazing. The radially inner face (46) of the tip (30) is inclined so as to define an inner clearance face which has the necessary circumferential and radial clearances without therebeing any need to grind the inner face (46) after brazing.
    Type: Grant
    Filed: August 11, 1992
    Date of Patent: September 21, 1993
    Assignee: Rotabroach Limited
    Inventor: Derrick Merrill
  • Annular hole cutter
    Patent number: 5218888
    Abstract: A tipped annular hole cutter is made by brazing all the cutting tips (30) simultaneously to the cylindrical wall (12) of the cutter body. The tips (30) have outer and inner lands (32, 34) which locate against the outer and inner surfaces (52, 54) of the cylindrical wall (12). This accurately locates the tips radially during brazing. The radially inner face (46) of the tip (30) is inclined so as to define an inner clearance face which has the necessary circumferential and radial clearances without therebeing any need to grind the inner face (46) after brazing.
    Type: Grant
    Filed: September 25, 1990
    Date of Patent: June 15, 1993
    Assignee: Rotabroach Limited
    Inventor: Derrick Merrill