Granted Patent
Utility
US 4,729,607 · App. 07/009,426
Dual circuit brake valve differential pressure control mechanism
Inventor:
Duane R. Johnson
Patented Case
View Patent ↗
Granted: Mar 8, 1988
Filed: Feb 2, 1987
Inventor
Duane R. Johnson
Assignee (at issue)
ALLIED CONSULTING, 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.