Patents by Inventor Robert E. Grunstra

Robert E. Grunstra 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).

  • Publication number: 20110094698
    Abstract: A ceramic core is produced by introducing a fluid ceramic core material, such as a ceramic slurry, into a core-shaped cavity formed at least in part by one or more fugitive core tooling liners residing in a back-up body, removing the ceramic core from the cavity, and removing the one or more fugitive tooling liners from the back-up die body and discarding them. The fugitive tooling liners and optional tooling inserts are used in one or more production cycles (e.g. ceramic slurry injection cycle) to make a single or multiple ceramic cores and then replaced with fresh (un-used) tooling liners and optional inserts to make other ceramic cores.
    Type: Application
    Filed: October 28, 2009
    Publication date: April 28, 2011
    Inventor: Robert E. Grunstra
  • Patent number: 7278460
    Abstract: A ceramic core for use in casting an article such as for example an airfoil, wherein the ceramic core has a pocket located at or near a region of the core that is otherwise associated with occurrence of a localized casting defect in the cast article. A covering is disposed on the core to cover the pocket and provide core outer surface features.
    Type: Grant
    Filed: May 10, 2006
    Date of Patent: October 9, 2007
    Assignee: Howmet Corporation
    Inventors: Robert E. Grunstra, John Corrigan
  • Patent number: 7234506
    Abstract: A ceramic core for use in casting an article such as for example an airfoil, wherein the ceramic core has a pocket located at or near a region of the core that is otherwise associated with occurrence of a localized casting defect in the cast article. A covering is disposed on the core to cover the pocket and provide core outer surface features.
    Type: Grant
    Filed: May 10, 2006
    Date of Patent: June 26, 2007
    Assignee: Howmet Research Corporation
    Inventors: Robert E. Grunstra, John Corrigan
  • Patent number: 7093645
    Abstract: A ceramic core for use in casting an article such as for example an airfoil, wherein the ceramic core has a pocket located at or near a region of the core that is otherwise associated with occurrence of a localized casting defect in the cast article. A covering is disposed on the core to cover the pocket and provide core outer surface features.
    Type: Grant
    Filed: December 20, 2004
    Date of Patent: August 22, 2006
    Assignee: Howmet Research Corporation
    Inventors: Robert E. Grunstra, John Corrigan
  • Patent number: 5706881
    Abstract: A method of making a single crystal or columnar grain superalloy casting comprises casting a superalloy in a mold wherein at least one of the mold and optional core comprises an oxygen-bearing ceramic, directionally solidifying the superalloy to form a single crystal or columnar grain superalloy casting, and solution heat treating the superalloy casting. The heat treatment is conducted under an atmosphere including a carbon-bearing gas, such as a carbon monoxide and inert gas mixture, wherein the carbon-bearing gas is present in an effective amount to reduce loss of carbon from the casting during the heat treatment. The heat treatment can be conducted prior to removal of all of the mold and core, if present, such as, for example, when the cast mold is in the as-knocked out condition wherein residual mold and/or core material is present on the casting. Alternately, the heat treatment can be conducted after removal of the mold and core, if present.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: January 13, 1998
    Assignee: Howmet Research Corporation
    Inventors: Robert E. Grunstra, Julie A. Faison, Jacqueline B. Wahl
  • Patent number: 4612969
    Abstract: A method and ceramic mold structure for use in producing articles having a predetermined crystalline orientation such as single crystals. The technique involves the use of a ceramic mold mounted on a chill plate with the mold defining a cavity tilted at an angle between about 5.degree. and 75.degree. relative to the vertical. One or more seed crystals are supported adjacent the chill plate and the orientation of the crystal is selected to provide a desired orientation in the resulting casting. The method results in improved solidification control, particularly with reference to avoiding defects caused by shrinkage.
    Type: Grant
    Filed: April 27, 1983
    Date of Patent: September 23, 1986
    Assignee: Howmet Turbine Components Corporation
    Inventors: Lamar Burd, Evan R. Miller, Eugene J. Carozza, Robert E. Grunstra
  • Patent number: 4580613
    Abstract: A mold construction and method for use in producing articles having a predetermined crystalline orientation including single crystals. The technique employs a seed holder or cradle that is inserted into a bottom aperture of a ceramic mold to permit the precise orientation of one or more seeds relative to the article cavity and to provide improved solidification process control. The technique also facilitates pattern assembly and pattern removal operations during fabrication of the ceramic mold.
    Type: Grant
    Filed: August 5, 1982
    Date of Patent: April 8, 1986
    Assignee: Howmet Turbine Components Corporation
    Inventors: Evan R. Miller, Lamar Burd, Eugene J. Carozza, Robert E. Grunstra