Granted Patent
Utility
US 4,272,952 · App. 06/037,185
Plastic chain and tubular link pin
Inventor:
Richard B. Graham
Patented Case
View Patent ↗
Granted: Jun 16, 1981
Filed: May 8, 1979
Inventor
Richard B. Graham
Assignee (at issue)
Dresser Industries, 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.