Patents Represented by Attorney, Agent or Law Firm R. G. Heywood
  • Patent number: 6374932
    Abstract: The invention is embodied in an earth boring tool comprising a bit body having a rotatable working head portion with a cutter element having a wear table of superhard material bonded to a substrate, and wherein the superhard and substrate materials have different coefficient properties creating a stress condition at their interface during bonding and wherein the cutter elements are stress relieved in situ on the bit body by low temperature heat annealing for a preselected time, and in which the cutter elements and bit body head portion are constructed and arranged for heat management in a dry, vacuum drilling operation. The invention further involves the heat management system and method of the stress relief process of heat annealing PCD cutter elements in situ, either alone or with a subsequent cryogenic tempering process.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: April 23, 2002
    Inventor: William J. Brady
  • Patent number: D457016
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: May 14, 2002
    Assignee: Duke Manufacturing Company
    Inventor: William R. Dudley
  • Patent number: D457020
    Type: Grant
    Filed: December 3, 2001
    Date of Patent: May 14, 2002
    Assignee: Duke Manufacturing Company
    Inventor: William R. Dudley
  • Patent number: D457361
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: May 21, 2002
    Assignee: Duke Manufacturing Company
    Inventor: William R. Dudley
  • Patent number: D457362
    Type: Grant
    Filed: December 3, 2001
    Date of Patent: May 21, 2002
    Assignee: Duke Manufacturing Company
    Inventor: William R. Dudley
  • Patent number: D458059
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: June 4, 2002
    Assignee: Duke Manufacturing Company
    Inventor: William R. Dudley
  • Patent number: D461073
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: August 6, 2002
    Assignee: Duke Manufacturing Company
    Inventor: William R. Dudley