Patents by Inventor Robert C. Zinkgraf

Robert C. Zinkgraf 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).

  • Covered dish
    Patent number: D256646
    Type: Grant
    Filed: March 8, 1979
    Date of Patent: September 2, 1980
    Assignee: Dart Industries Inc.
    Inventors: David L. Painter, Robert C. Zinkgraf
  • Roasting pan
    Patent number: D256647
    Type: Grant
    Filed: March 8, 1979
    Date of Patent: September 2, 1980
    Assignee: Dart Industries Inc.
    Inventors: David L. Painter, Robert C. Zinkgraf
  • Dish
    Patent number: D256648
    Type: Grant
    Filed: March 8, 1979
    Date of Patent: September 2, 1980
    Assignee: Dart Industries Inc.
    Inventors: David L. Painter, Robert C. Zinkgraf
  • Roasting rack
    Patent number: D256653
    Type: Grant
    Filed: March 8, 1979
    Date of Patent: September 2, 1980
    Assignee: Dart Industries Inc.
    Inventors: David L. Painter, Robert C. Zinkgraf
  • Combined roasting pan and rack
    Patent number: D256654
    Type: Grant
    Filed: March 8, 1979
    Date of Patent: September 2, 1980
    Assignee: Dart Industries Inc.
    Inventors: David L. Painter, Robert C. Zinkgraf
  • Plate
    Patent number: D256756
    Type: Grant
    Filed: March 8, 1979
    Date of Patent: September 9, 1980
    Assignee: Dart Industries Inc.
    Inventors: David L. Painter, Robert C. Zinkgraf
  • Pitcher
    Patent number: D257311
    Type: Grant
    Filed: March 8, 1979
    Date of Patent: October 14, 1980
    Assignee: Dart Industries Inc.
    Inventors: David L. Painter, Robert C. Zinkgraf
  • Tea pot
    Patent number: D257313
    Type: Grant
    Filed: March 8, 1979
    Date of Patent: October 14, 1980
    Assignee: Dart Industries Inc.
    Inventors: David L. Painter, Robert C. Zinkgraf
  • Pan
    Patent number: D259382
    Type: Grant
    Filed: March 8, 1979
    Date of Patent: June 2, 1981
    Assignee: Dart Industries Inc.
    Inventors: David L. Painter, Robert C. Zinkgraf