Granted Patent
Utility
US 4,249,625 · App. 06/021,802
Drive system for crawler propelled machines
Inventor:
Michael Palm
Patented Case
View Patent ↗
Granted: Feb 10, 1981
Filed: Mar 19, 1979
Inventor
Michael Palm
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.