Patents by Inventor F. James Thornton

F. James Thornton 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: 4552231
    Abstract: Coring samples can be taken in highly fractured rock formations without physical disturbance of the coring sample as it is cut and without jamming the core within the core barrel by using a rotating coring bit characterized by a pilot portion. The pilot portion extends the inner gage to form a longitudinally extending cylindrical surface. The nose of the pilot portion is characterized by a crowned surface wherein cylindrical polycrystalline diamond (PCD) cutting elements are axially disposed and longitudinally extending from the crowned surface. The width of the crowned surface which forms the nose of the pilot portion, is substantially less than the distance between the inner and outer gages of the coring bit. The pilot portion joins a flank portion of the bit through a cylindrical and longitudinally extending pilot gage.
    Type: Grant
    Filed: September 6, 1983
    Date of Patent: November 12, 1985
    Assignee: Norton Christensen, Inc.
    Inventors: Clifford R. Pay, F. James Thornton