Granted Patent
Utility
US 4,699,577 · App. 06/860,715
Internal gear device with improved rotary valve
Inventors:
Andrew N. Dlugokecki, Carle A. Middlekauff
Patented Case
View Patent ↗
Granted: Oct 13, 1987
Filed: May 6, 1986
Inventors
Andrew N. Dlugokecki
Carle A. Middlekauff
Assignee (at issue)
Parker-Hannifin Corporation
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.