Patents Assigned to Certech Incorporated
  • Method of forming hollow ceramic articles
    Patent number: 5798066
    Abstract: A method of forming a hollow ceramic article includes the steps of providing a mold having a wall defining a cavity and injecting into the cavity through an inlet through the cavity wall a quantity of a slurry sufficient to fill the cavity. The slurry is formed by a molten thermoplastic binder and ceramic particles suspended in the binder. The portion of the slurry in contact with the cavity wall is cooled to solidify the same, while leaving still molten the portion of the slurry not in contact with the cavity wall. Gas is injected into the cavity through an inlet through the cavity wall and into the still molten slurry portion to force the same out of the cavity through an outlet through the cavity wall. This leaves therein only the gas and a hollow green piece formed from the solidified slurry portion.
    Type: Grant
    Filed: July 12, 1995
    Date of Patent: August 25, 1998
    Assignee: Certech Incorporated
    Inventor: Stuart Z. Uram
  • Impregnated ceramic core and method of making same
    Patent number: 5460854
    Abstract: A method of strengthening a fired porous ceramic core for use in investment casting includes the steps of providing a fired porous ceramic core, impregnating the core with an aqueous solution of a water-soluble gum, resin, or sugar, such as polyvinyl alcohol, and drying the impregnated core to remove the water.
    Type: Grant
    Filed: January 16, 1992
    Date of Patent: October 24, 1995
    Assignee: Certech Incorporated
    Inventor: Eugene Krug
  • Method of forming a ceramic mold for metal casting
    Patent number: 5067548
    Abstract: Individual mold sections are injection molded from a slurry of ceramic particles and a binder. Each of the green individual mold sections is low temperature fired to remove therefrom a major portion of the binder while leaving therein a minor portion of the binder sufficient to afford structural strength thereto, and the individual mold sections are assembled together to form a mold. Finally the mold is high temperature fired to complete removal of the binder.
    Type: Grant
    Filed: March 19, 1991
    Date of Patent: November 26, 1991
    Assignee: Certech Incorporated
    Inventor: Stuart Z. Uram
  • Molten metals filter apparatus
    Patent number: 4671498
    Abstract: A molten metals filter apparatus having a hollow strainer, including an inlet port and a plurality of slot apertures having a uniform width for selectively restraining particulant impurities in molten metals.
    Type: Grant
    Filed: April 9, 1985
    Date of Patent: June 9, 1987
    Assignee: Certech Incorporated
    Inventor: Stuart Z. Uram
  • Molten metals filter apparatus
    Patent number: 4576219
    Abstract: A molten metals filter apparatus having a hollow frusto-conical strainer, including an inlet port and a plurality of slot apertures having a uniform width for selectively restraining particulant impurities in molten metals.
    Type: Grant
    Filed: October 22, 1982
    Date of Patent: March 18, 1986
    Assignee: Certech Incorporated
    Inventor: Stuart Z. Uram
  • Molten metals filter
    Patent number: D279379
    Type: Grant
    Filed: October 22, 1982
    Date of Patent: June 25, 1985
    Assignee: Certech Incorporated
    Inventor: Stuart Z. Uram