Patents by Inventor Robert P. Hallissy

Robert P. Hallissy 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: 4770253
    Abstract: A grader blade has a steel body with a bottom edge incorporating a pair of tiered, elongated carbide inserts in a forward portion thereof. The carbide inserts, being arranged in a tiered contacting relationship, are disposed in a stepped recess formed in and along the forward portion of the bottom edge of the blade body and brazed to the blade body and to each other so as to project forwardly and downwardly from the recess. A front one of the tiered inserts is composed of a cemented carbide composition having a high cobalt content, for instance 20 percent by weight, adapting it for enhanced impact wear resistance, whereas a rear one of the tiered inserts is composed of a cemented carbide composition having a low cobalt content, for instance 11.5 percent by weight, adapting it for enhanced downpressure wear resistance.
    Type: Grant
    Filed: February 20, 1987
    Date of Patent: September 13, 1988
    Assignee: Kennametal Inc.
    Inventors: Robert P. Hallissy, Edmund Isakov, John F. Kita, Earle W. Stephenson
  • Patent number: 4715450
    Abstract: A grader blade has a steel body with a bottom edge incorporating a substrate of air-hardened tool steel casting material assembling a preformed cemented carbide insert in tiered relationship with, and rearwardly of, a casted layer of carbide grit. The front casted carbide grit layer is formed in the casting operation and the rear preformed cemented carbide insert is arranged in the tiered contacting and attached relationship with the carbide grit layer as the latter is casted with the substrate of special steel casting that holds the insert and layer together. The steel body of the blade also includes a recess formed in and along the forward portion of the blade bottom edge into which the casted asembly is disposed and welded to the blade.
    Type: Grant
    Filed: February 20, 1987
    Date of Patent: December 29, 1987
    Assignee: Kennametal Inc.
    Inventors: Robert P. Hallissy, Edmund Isakov, Earle W. Stephenson, Don C. Rowlett