Patents by Inventor Robert F. Leu

Robert F. Leu 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: 4148161
    Abstract: A bur grinding machine especially adapted to grind dental burs and including a turntable supporting a plurality of similar workheads having collets to support bur blanks; a plurality of grinding units mounted on a stationary base in circumferentially spaced locations around the periphery of said table and respectively operable to perform different grinding operations in sequence upon the heads of bur blanks; means to index, rotate, and advance the collets of the workheads automatically at each grinding unit to form a plurality of teeth upon the bur blanks; means to index said table to advance the burs in the workheads to the next grinding unit; means to feed and accurately position bur blanks within the collets of the workheads; and means to control the cycle of the machine throughout.
    Type: Grant
    Filed: November 22, 1977
    Date of Patent: April 10, 1979
    Assignee: Dentsply Research & Development Corp.
    Inventors: William McCandless, Robert F. Leu, Ernest A. Kroder, Charles J. Tomecek
  • Patent number: 4106242
    Abstract: A bur grinding machine especially adapted to grind dental burs and including a turntable supporting a plurality of similar workheads having collets to support bur blanks; a plurality of grinding units mounted on a stationary base in circumferentially spaced locations around the periphery of said table and respectively operable to perform different grinding operations in sequence upon the heads of bur blanks; means to index, rotate, and advance the collets of the workheads automatically at each grinding unit to form a plurality of teeth upon the bur blanks; means to index said table to advance the burs in the workheads to the next grinding unit; means to feed and accurately position bur blanks within the collets of the workheads; and means to control the cycle of the machine throughout.
    Type: Grant
    Filed: May 2, 1977
    Date of Patent: August 15, 1978
    Assignee: Dentsply Research & Development Corp.
    Inventors: William McCandless, Robert F. Leu, Ernest A. Kroder, Charles J. Tomecek
  • Patent number: 4052821
    Abstract: A bur grinding machine especially adapted to grind dental burs and including a turntable supporting a plurality of similar workheads having collets to support bur blanks; a plurality of grinding units mounted on a stationary base in circumferentially spaced locations around the periphery of said table and repsectively operable to perform different grinding operations in sequence upon the heads of bur blanks; means to index, rotate, and advance the collets of the workheads automatically at each grinding unit to form a plurality of teeth upon the bur blanks; means to index said table to advance the burs in the workheads to the next grinding unit; means to feed and accurately position bur blanks within the collets of the workheads; and means to control the cycle of the machine throughout.
    Type: Grant
    Filed: March 15, 1976
    Date of Patent: October 11, 1977
    Assignee: Dentsply Research & Development Corporation
    Inventors: William McCandless, Robert F. Leu, Ernest A. Kroder, Charles J. Tomecek
  • Patent number: 3971135
    Abstract: A helical dental bur having a shank provided on one end with a cutting head having a series of similar teeth extending longitudinally and spaced evenly around the circumference thereof; said teeth each having a flat cutting face extending from the cutting edge radially toward the axis of the head to form one side of said tooth and provide a positive cutting rake therefor, a relative deep chip gash adjacent said face, and a convex relief surface extending from the cutting edge toward said gash adjacent the next succeeding tooth to form the opposite side of each tooth, said convex relief surface permitting said chip gashes to be substantially deeper than such gashes in conventional burs without sacrificing strength of said teeth to resist chipping and breakage of said cutting edges, as well as including the benefit of said flat cutting face which extends radially to provide said positive cutting rake.
    Type: Grant
    Filed: September 4, 1975
    Date of Patent: July 27, 1976
    Assignee: Dentsply Research & Development Corporation
    Inventor: Robert F. Leu