Granted Patent
Utility
US 4,993,263 · App. 07/354,014
Plastic hydrometer
Inventors:
Ravinder C. Mehra, Paul V. Comeau
Patented Case
View Patent ↗
Granted: Feb 19, 1991
Filed: May 19, 1989
Inventors
Ravinder C. Mehra
Paul V. Comeau
Assignee (at issue)
Nalge Company
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.