Granted Patent
Utility
US 4,830,589 · App. 07/241,461
Variable stroke positive displacement pump
Inventor:
Ramon Pareja
Patented Case
View Patent ↗
Granted: May 16, 1989
Filed: Sep 8, 1988
Inventor
Ramon Pareja
Assignee (at issue)
Hypro, LLC
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.