Granted Patent
Utility
US 6,467,657 · App. 09/948,944
Pump assembly with one piece piston
Inventors:
Donald J. Shanklin, Ronald F. Englhard
Patented Case
View Patent ↗
Granted: Oct 22, 2002
Filed: Sep 5, 2001
Inventors
Donald J. Shanklin
Ronald F. Englhard
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.