Granted Patent
Utility
US 5,975,752 · App. 09/030,630
Fabricated steel lifter for rotary kiln
Inventor:
Brian Doerksen
Patented Case
View Patent ↗
Granted: Nov 2, 1999
Filed: Feb 25, 1998
Inventor
Brian Doerksen
Assignee (at issue)
Conoco 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.