Patents by Inventor Robert K. Bjerke

Robert K. Bjerke 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: 5216199
    Abstract: A method of manufacturing an improved lead-free primed rimfire cartridge for ammunition or industrial powerloads providing a gas source for driving fasteners with power-fastening tools. A lead-free priming mixture is consolidated into an annular cavity of a rimfire casing and dried in the cavity. The primer is secured in the cavity by tamping at least a portion of propellant into the casing against and over the dried primer. The tamping pressure per casing may range from 1,300 psi to 8,800 psi. Any remaining portion of required propellent is added over the tamped compacted propellant layer. The ammunition and powerload casings are then sealed and finished in a conventional manner. A rimfire cartridge for both ammunition and industrial powerload applications manufactured as described above is also provided.
    Type: Grant
    Filed: July 8, 1991
    Date of Patent: June 1, 1993
    Assignee: Blount, Inc.
    Inventors: Robert K. Bjerke, Kenneth P. Kees, James P. Ward, Walter H. Stevens
  • Patent number: 4963201
    Abstract: Primer composition comprising diazodinitrophenol or potassium dinitrobenzofuroxane, tetracene, nitrate ester fuel and strontium nitrate. It is prepared by hydrating anhydrous strontium nitrate by dissolving in warm water and thereafter cooling solution to obtain crystals of the tetrahydrate. These crystals are mixed with other components to form the primer composition.
    Type: Grant
    Filed: January 10, 1990
    Date of Patent: October 16, 1990
    Assignee: Blount, Inc.
    Inventors: Robert K. Bjerke, James P. Ward, Delbert O. Ells, Kenneth P. Kees
  • Patent number: 4608102
    Abstract: A primer composition using manganese dioxide as the predominant oxidizer is disclosed. The manganese dioxide oxidizer is combined with a fuel source and non-metallic initiating explosive material. Various diazo, triazole, or tetrazole compounds may be used as non-metallic initiating explosives, although diazodinitrophenol is preferred. The combustion by-products of the invention do not include toxic oxides of lead, barium, or mercury. The invention therefore provides distinct safety and environmental advantages.
    Type: Grant
    Filed: November 14, 1984
    Date of Patent: August 26, 1986
    Assignee: Omark Industries, Inc.
    Inventors: Adalbert A. Krampen, Delbert O. Ells, Robert K. Bjerke, James P. Ward