Granted Patent
Utility
US 4,296,748 · App. 06/052,825
Underwater drainage apparatus with separable suction control chamber
Inventors:
Leonard D. Kurtz, Robert E. Bidwell
Patented Case
View Patent ↗
Granted: Oct 27, 1981
Filed: Jun 27, 1979
Inventors
Leonard D. Kurtz
Robert E. Bidwell
Assignee (at issue)
Bioresearch, 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.