Granted Patent
Utility
US 4,912,418 · App. 07/206,271
Method and device for detecting the location of a fault within a dielectric layer of an electrically conducting pipe
Inventor:
Rainer Trampert
Patented Case
View Patent ↗
Granted: Mar 27, 1990
Filed: Jun 13, 1988
Inventor
Rainer Trampert
Assignee (at issue)
Pfaudler-Werke GmbH
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.