Granted Patent
Utility
US 6,247,921 · App. 08/652,740
Apparatus for generating a spark
Inventor:
Robert W. Helt
Patented Case
View Patent ↗
Granted: Jun 19, 2001
Filed: May 23, 1996
Inventor
Robert W. Helt
Assignee (at issue)
American Standard International Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.