Granted Patent
Utility
US 4,322,933 · App. 06/181,273
Stone trapdoor trip mechanism
Inventor:
Shaun A. Seymour
Patented Case
View Patent ↗
Granted: Apr 6, 1982
Filed: Aug 25, 1980
Inventor
Shaun A. Seymour
Assignee (at issue)
Sperry Corp.
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.